TY - CONF A1 - Pentzien, Simone A1 - Rabin, Ira A1 - Hahn, Oliver A1 - Krüger, Jörg A1 - Kleber, F. A1 - Hollaus, F. A1 - Diem, M. A1 - Sablatnig, R. ED - Park, J.-I. ED - Kim, J. T1 - Can Modern Technologies Defeat Nazi Censorship? N2 - Censorship of parts of written text was and is a common practice in totalitarian regimes. It is used to destroy information not approved by the political power. Recovering the censored text is of interest for historical studies of the text. This paper raises the question, whether a censored postcard from 1942 can be made legible by applying multispectral imaging in combination with laser cleaning. In the fields of art conservation (e.g. color measurements), investigation (e.g. Analysis of underdrawings in paintings), and historical document analysis, multispectral imaging techniques have been applied successfully to give visibility to information hidden to the human eye. The basic principle of laser cleaning is to transfer laser pulse energy to a contamination layer by an absorption process that leads to heating and evaporation of the layer. Partial laser cleaning of postcards is possible; dirt on the surface can be removed and the obscured pictures and writings made visible again. We applied both techniques to the postcard. The text could not be restored since the original ink seems to have suffered severe chemical damage. T2 - ACCV 2012 Workshops, 11th Asian conference on computer vision CY - Daejeon, Korea DA - 05.11.2012 KW - Laser cleaning KW - Multispectral imaging KW - Image restoration KW - Image enhancement PY - 2013 SN - 978-3-642-37483-8 SN - 0302-9743 VL - II IS - LNCS 7729 SP - 13 EP - 24 PB - Springer CY - Berlin Heidelberg AN - OPUS4-28160 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheid, Marc A1 - Kusche, Christian A1 - Schröder, Volkmar A1 - Barth, Uli ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Tests on suitability of the ignition source 'exploding wire' for the determination of explosion characteristics of combustible dusts in the 20-L-sphere N2 - According to international standards several safety characteristics of dusts are determined in the 20-Lsphere (also known as SIWEK Chamber). Dust cloud ignition is carried out using pyrotechnical igniters. Due to various disadvantages of such igniters the need for alternative ignition sources arises again and again. An alternative ignition source could be the so called 'exploding wire' or 'fuse wire'. The paper presents test results of a comparative study between both ignition sources for the determination of the safety characteristics Maximum Explosion Pressure and Maximum Explosion Pressure Rise of five selected dusts in the 20-L-sphere. In addition to that the ignition mechanisms of both ignition sources were analysed by high speed camera recordings and the ignition energy was determined with electric and calorimetric recordings. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Sicherheitstechnische Kenngrößen Staub KW - Staubexplosionsschutz KW - Explodierender Draht KW - Alternative Zündquelle PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331118 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 703 EP - 708 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28554 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krietsch, Arne A1 - Romahn, T.-M. A1 - Scheid, Marc A1 - Krause, U. ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Modified setup of 20-L-sphere for the determination of safety characteristics of nano powders N2 - This paper describes a modified experimental setup for the test apparatus 20-L-Sphere (also known as 20-L Siwek Chamber), that enables the test samples to be kept under inert atmospheric conditions nearly until ignition. This setup was designed to allow the determination of safety characteristics of nanopowders under most critical circumstances (e.g. minimisation of the influence of oxidation before the test itself). The aim of this modification was to determine, whether or not the current setup and procedures underestimate the explosion violence and ignitability of nanopowders. The work includes experimental results of micrometer dusts to validate the modified setup. Moreover first results of nanometer iron and Aluminium dusts are presented, which were kept at inert conditions until shortly before the ignition. The tested nano iron was found to react pyrophoric, as soon as it gets in contact with air, while the tested nano Aluminium did not generally show such behaviour. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Dust explosion KW - Nanopowder PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331135 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 805 EP - 810 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28561 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rohwetter, Philipp A1 - Habel, Wolfgang ED - Jaroszewicz, L.R. T1 - Fibre-optic sensors for partial discharge-generated ultrasound in elastomeric high-voltage insulation materials N2 - Recent progress in the development of ultrasonic fibre-optic sensors for detecting acoustic emission from partial discharge in elastomeric insulations is presented. These sensors are an important part of a proposed comprehensive scheme for the fibre-optic monitoring of cable accessories. After specifying the underlying design goals the improved fibre-optic sensor design is outlined. It is experimentally shown that it offers about ten-fold improvement over a previously investigated resonant cantilever-type design in terms of detection limit, making it competitive with conventional piezoelectric transducers, however with the added compatibility with strong electrical fields and electromagnetically noisy environments. T2 - EWOFS 2013 - 5th European workshop on optical fibre sensors CY - Kraków, Poland DA - 2013-05-19 KW - Acoustic emission KW - Fiber optics sensors KW - Sensors KW - Transducers KW - Ultrasonics KW - Ultrasonography KW - Fiber-optic condition monitoring KW - Partial discharge KW - Silicone elastomer KW - Stress cone KW - High-voltage cable accessories KW - Sagnac interferometer KW - Acoustic waveguide PY - 2013 SN - 978-0-819-49634-8 DO - https://doi.org/10.1117/12.2025824 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 8794 IS - 181 SP - 879407-1 EP - 879407-4 AN - OPUS4-28563 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Schwarzer, Stefanie A1 - Otremba, Frank ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Comparison of the operating life of tank containers, tank vehicles and rail cars for the carriage of dangerous goods in practice, analysis of causes of damage N2 - More than 400 Mt of dangerous materials are transported in Germany every year, of which 150 Mt are by road. Tank containers, tank vehicles and rail tank cars are used for the carriage of dangerous goods in large quantities. Data on the operating life of tanks are only available, in practice, to a minor degree. They are only partly published, mainly after accidents. The BAM-List - Requirements for Tanks for the Carriage of Dangerous Goods, which has compatibility evaluations of metallic and polymeric materials, has been the basis for substance-related prototype approvals for tank containers and portable tanks designed for the carriage of dangerous goods by the BAM since publication of the first edition in 1989. These data are also used for the approval of rail tank cars and road tank cars and are used as a source of knowledge not only in Germany but also worldwide. Tank leakages caused by tanks or rail tank cars being made of tank and sealing materials which are not resistant to the fill goods are avoided by using the material resistance data of the BAM. Corrosion damage is among the main causes of damage. Uniform and non-uniform area corrosion without mechanical stress in aqueous substances is one of the most frequent types of corrosion during the transport of chemicals in tanks. Much damage by pitting corrosion occurs during the transport of substances containing chlorides or substances which separate chloride ions in the presence of moisture. Operational stresses are caused by the effects of both the road and the dangerous goods being transported. Mechanical damage often results from long-term overstressing and occurs after longer operating times. Operational failures cause damage which may appear during the service of tank containers, road tank cars or rail tank cars. The damage results from the inattention of employees when opening and closing the valves. Traffic accidents also cause damage to tanks and frames. Many cases of damage are due to weld area cracks resulting from four basic errors in construction, material, manufacturing and operation. Manufacturing errors can be undetected and the starting point of cracks which only grow under service conditions. Manufacturing errors result from variations in measurement and design, fittings, state of surface (hardness, abrasiveness) and mechanical surface damage (scratches, cracks). Incorrectly welded joints and errors during mechanical deformation are typical mistakes when installing the component parts. Variations in the wall thickness or combinations of different materials lead to manufacturing errors too. A lot of tanks are not used for the transport of dangerous goods before the end of their service life as they do not fulfil the revised technical safety requirements in the Dangerous Goods Regulations. Predictions in the BAM-List based on literature data and corrosion test results are reflected in the service (operating) life. Rail tank cars made of carbon steel, for example, which are mainly used for the transport of petroleum products, can achieve a service life of 40 – 50 y. Rail tank cars produced of austenitic CrNi- or CrNiMo-steel can reach an operating life of at least 30 y, whereby the corrosiveness of the transport substances plays an important role. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Gefahrguttanks KW - Eisenbahnkesselwagen KW - Schadensursachen KW - Lebensdauer PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331094 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 559 EP - 564 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28568 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kusche, Nadine A1 - Schukar, Vivien A1 - Hofmann, Detlef A1 - Basedau, Frank A1 - Habel, Wolfgang A1 - Woschitz, H. A1 - Lienhart, W. ED - Jaroszewicz, L.R. T1 - Field examples for optical fibre sensor condition diagnostics based on distributed fibre-optic strain sensing N2 - Fibre optic sensors for monitoring in safety-relevant structures have to be validated in order to proof their reliability under typical structural load conditions. The reliable use of optical fibre sensors depends strongly on an appropriate and qualitative application. Diagnostics of the physical condition of embedded and surface-applied fibre optic strain sensors are demonstrated on field examples. Distributed strain measurement based on Rayleigh backscattering is used to determine breakage of the fibre, interface adhesion problems and to identify application related strain transfer mechanisms. T2 - EWOFS 2013 - 5th European workshop on optical fibre sensors CY - Kraków, Poland DA - 19.05.2013 KW - Fibre Bragg grating KW - Rayleigh backscattering KW - Condition diagnostics KW - Strain KW - Strain transfer PY - 2013 SN - 978-0-81949-634-8 DO - https://doi.org/10.1117/12.2025567 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 8794 IS - Paper 8794 - 181 SP - 879433-1 EP - 879433-4 AN - OPUS4-28570 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Malow, Marcus A1 - Berger, Anka A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Mass burning rate of a large TBPB pool fire - experimental study and modeling N2 - Data and prediction for the mass burning rate of a tert-butyl-peroxy-benzoat (TBPB) pool fire (pool diameter = 3 m) is presented. The mass burning rates of TBPB fires are up to six times higher and less dependent on pool diameter compared to hydrocarbon pool fires caused by an additional heat release rate due to exothermic decomposition reaction in the liquid phase. This heat release rate is calculated using a 1st order reaction kinetic obtained from micro calorimetric measurements. A new model is derived considering the heat release rate due to the decomposition reaction which is shown to be 100 % of the heat release rate radiated to the pool surface. With the presented model, including also physical quantities, especially the limiting fuel concentration for upward flame propagation, it is possible to predict the mass burning rates of large TBPB pool fires. The predicted values are in very good agreement with the experiments. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Mass burning rate KW - TBPB (tert-butyl-peroxy benzoat) KW - Pool fire KW - Experimental study KW - Modeling PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331143 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 853 EP - 858 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28501 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zencker, Uwe A1 - Qiao, Linan A1 - Kasparek, Eva Maria A1 - Völzke, Holger T1 - Modeling of cylindrical casks under horizontal drop test conditions N2 - Cylindrical casks made of ductile cast iron are used for transport, interim storage and final disposal of radioactive waste in Germany. A basic design criterion is the ability to withstand a horizontal drop without impact Binders onto a foundation representative for the real ground of a storage facility. The increasing use of more cost-effective material compositions requires optimized cask geometries to reduce stresses and strains in the cask structure. For example, a non-uniform wall thickness was introduced to reduce maximum wall bending stresses. As a result, the load characteristics changed from line load to point load at bottom and lid side under horizontal drop fest conditions. Hereby, the position of highest stress inside the structure has shifted significantly. This was the reason for a systematic investigation of effects caused by small design changes or small variations of fest conditions. It led to a better understanding of the positions of high local stresses, their time history and maximum value for cylindrical casks under horizontal drop test conditions. Hence, the paper presents the lessons learnt from modeling and simulating such scenarios considering an impact without limiters onto a realistic target. T2 - 14th International high-level radioactive waste management conference CY - Albuquerque, New Mexico, USA DA - 28.04.2013 KW - Cylindrical cask KW - Ductile cast iron KW - Numerical simulation KW - Horizontal drop test KW - Storage facility KW - Concrete foundation PY - 2013 SN - 978-1-62748-644-6 SP - 1114 EP - 1119 (Paper # 6862) PB - Omnipress AN - OPUS4-28529 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wolff, Dietmar A1 - Jaunich, Matthias A1 - Stark, Wolfgang T1 - Investigating the performance of rubber seals at low temperatures N2 - Rubbers are widely used as main sealing materials for Containers for low and intermediate level radioactive waste and as additional component to metal seals in spent fuel and high active waste containers. The save enclosure of the radioactive container inventory has to be guaranteed according to legislation and appropriate guidelines for long term storage periods as well as down to temperatures of -40 °C for transportation. Therefore the understanding of failure mechanisms that lead to leakage at low temperatures is necessary to ensure a proper material choice which is certainly also influenced by additional factors as e.g. the aging behavior. T2 - 14th International high-level radioactive waste management conference CY - Albuquerque, New Mexico, USA DA - 28.04.2013 KW - Rubber seals KW - Elastomers KW - Compression set KW - Low temperature KW - Leakage rate PY - 2013 SN - 978-1-62748-644-6 SP - 1 EP - 7(Paper # 6888) PB - Omnipress AN - OPUS4-28530 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfeil, Norbert A1 - Jochum, C. A1 - Mitropetros, K. A1 - Schmelzer, P.G. ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Keeping and improving process and plant safety competence - what is needed, what should be done? N2 - In March 2004 with the position paper “Maintaining and improving competence in safety engineering” of the DECHEMA/GVC Research Committee "Safety Engineering in Chemical Plants", an initiative came up against the tendency that more and more process and plant safety (PPS) orientated professorships turn to other more fashionable research topics. The Research Committee was concerned that PPS in both academic teaching and research could suffer a negative development - despite of its importance. In 2009 a corresponding Dutch initiative followed. To bring these both and other similar initiatives together, within the 8th European Congress of Chemical Engineering held in Berlin in September 2011 a two days Special session on PPS competence was jointly organized by EFCE, ProcessNet and EPSC. All presentations and conclusions drawn by the organizers (the authors of this paper) are electronically available. The paper addresses the before mentioned initiatives, highlights views and results from the ECCE 8’s special session on PPS competence, and indicates steps necessary to be taken and recent developments. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Anlagensicherheit KW - Prozessindustrie KW - Lehre KW - Forschung PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331063 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 373 EP - 378 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liehr, Sascha A1 - Burgmeier, J. ED - Jaroszewicz, L.R. T1 - Quasi-distributed measurement on femtosecond laser-induced scattering voids using incoherent OFDR and OTDR N2 - We propose to use focused femtosecond laser pulses to create scattering damage in standard singlemode optical fibres as reference points for quasi-distributed sensing applications. Such sensor fibres are interrogated with incoherent optical frequency domain reflectometry (I-OFDR) technique and optical time domain reflectometry (OTDR). A performance comparison of both techniques with the clear advantage of the I-OFDR is presented as well as a quasi-distributed length change measurement application. Also dynamic measurement based on the I-OFDR technique is demonstrated on a femtosecond laser-induced sensor chain. T2 - EWOFS 2013 - 5th European workshop on optical fibre sensors CY - Kraków, Poland DA - 19.05.2013 KW - Optical fiber sensors KW - Femtosecond laser KW - Strain sensor KW - OFDR KW - OTDR PY - 2013 SN - 978-0-81949-634-8 DO - https://doi.org/10.1117/12.2026780 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 8794 IS - Paper 8794 - 181 SP - 87943N-1 EP - 87943N-4 AN - OPUS4-28734 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gerlitzke, A.-K. A1 - Nörthemann, K. A1 - Lang, M. A1 - Milstrey, M. A1 - Kaufer, R. A1 - Woratz, M. A1 - Banach, Ulrich A1 - Hübert, Thomas A1 - Moritz, W. T1 - Long-term stability of the low energy hydrogen sensor N2 - A silicon MIS-structure prepared with thin layers of the super-ionic conductor LaF3 and Pd is used to detect hydrogen. The sensor is able to detect hydrogen in a concentration range from below one ppm to the lower flammable limit in air which is 4 vol.-%. The chip operates at room temperature which results in an extremely low energy consumption compared to other hydrogen sensors. Only once per day a short heating pulse is necessary to reactivate the sensor chip. In cooperation with the BAM, a long-term experiment was carried out. The duration of the measurement was about three months, with a hydrogen exposure every two weeks. The sensor signal remained stable over the measured period. T2 - IMCS 2012 - 14th International meeting on chemical sensors CY - Nuremberg, Germany DA - 20.05.2012 KW - Hydrogen detection KW - Long-term measurement KW - MIS-structure KW - Low energy sensor PY - 2012 SN - 978-3-9813484-2-2 DO - https://doi.org/10.5162/IMCS2012/P2.5.1 SP - 1571 EP - 1574 PB - AMA Service GmbH CY - Wunstorf AN - OPUS4-26177 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gravenkamp, Hauke A1 - Saputra, A. A. A1 - Song, C. A1 - Prager, Jens ED - Linde, B. B. J. ED - Paczkowski, J. ED - Ponikwicki, N. T1 - Detection of defects in thin-walled structures by means of lamb waves N2 - In this paper the Scaled Boundary Finite Element Method (SBFEM) is applied for the simulation of Lamb waves in cracked plates. This method is highly advantageous to study the interaction of different Lamb wave modes with cracks as the crack is not discretized and no refinement is required around the crack tip. Numerical examples are presented for the reflection of the fundamental symmetric and antisymmetric modes from cracks of different depth. The spatial Fourier transformation is employed to calculate the amplitudes of reflected Lamb wave modes. The results reveal possibilities to obtain details of the crack geometry in non-destructive testing and structural health monitoring applications. T2 - International congress on ultrasonics CY - Gdansk, Poland DA - 05.09.2011 KW - Lamb waves KW - Scaled boundary finite element method KW - Simulation KW - Crack detection PY - 2012 SN - 978-0-7354-1019-0 DO - https://doi.org/10.1063/1.3703223 SN - 0094-243X N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings IS - 1433 SP - 443 EP - 446 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-26203 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ballheimer, Viktor A1 - Wille, Frank A1 - Rolle, Annette A1 - Droste, Bernhard T1 - Mechanical behaviour of high burn-up SNF under normal and accident transport conditions - present approaches and perspectives N2 - Transport packages for spent fuel have to meet the International Atomic Energy Agency requirements for different transport conditions. Physical state of spent fuel and fuel rod cladding as well as geometric configuration of fuel assemblies are important inputs for the evaluation of package capabilities under these conditions. In this paper, the mechanical behaviour of high burn-up spent fuel assemblies under transport conditions is analysed with regard to assumptions to be used in the activity release and criticality safety analysis. In particular the different failure modes of the fuel rods (fine cracks or complete breakage), which can cause release of gas, volatiles, fuel particles or fragments have to be properly considered in these assumptions. In view of the complexity of interactions between the fuel rods as well as between fuel assemblies, basket, and cask containment, the exact mechanical analysis of such phenomena is nearly impossible. The gaps in information concerning the material properties of cladding and pellets, especially for the high burn-up fuel, make the analysis more complicated additionally. In this context some practical approaches based on experiences of BAM Federal Institute for Material Research and Testing within safety assessment of packages for transport of spent fuel are discussed. T2 - ASME 2012 Pressure vessels & piping division conference CY - Toronto, Ontario, Canada DA - 15.07.2012 KW - Fuel rods KW - High burn-up KW - Mechanical behaviour KW - Transport conditions PY - 2012 SP - PVP2012-78302, 1-7 PB - American Society of Mechanical Engineers CY - New York AN - OPUS4-26320 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schempp, Philipp A1 - Pittner, Andreas A1 - Rethmeier, Michael A1 - Tang, Z. A1 - Seefeld, T. A1 - Cross, C.E. ED - Babu, S. S. ED - Bhadeshia, H.K. ED - Cross, C.E. ED - David, S.A. ED - DebRoy, T. ED - DuPont, J.N. ED - Koseki, T. ED - Liu, S. T1 - Influence of alloy and solidification parameters on grain refinement in aluminium weld metal due to inoculation N2 - Refinement of the weld metal grain structure can improve the mechanical properties of the weld and decrease the susceptibility to solidification cracking of the weld metal. In this study, commercial Al Ti5B1 grain refiner was used to refine the microstructure of LB (laser beam) and GTA (gas tungsten arc) aluminum welds by inoculation. The grain refiner additions led to a significant decrease in the weld metal mean grain size whereby a transition from columnar to equiaxed grain structure (Columnar to Equiaxed Transition, CET) was observed. The development of both grain size and shape depended upon the base metal (Al alloys 1050A, 5083 and 6082) and upon the welding process. The GTA welding process allowed a more pronounced and a more efficient refinement than in LB welds. Furthermore, the influence of the solidification conditions on the CET was investigated through temperature measurements in the weld metal. The temperature profiles revealed a faster solidification of LB welds than in GTA welds. The results from the temperature measurements were also used to estimate (according to an existing model) the critical thermal gradient at which the CET occurs. T2 - 9th International conference on trends in welding research CY - Chicago, Illinois, USA DA - 04.06.2012 KW - Aluminium KW - LBW KW - GTAW KW - Grain refinement KW - Alloy 1050A KW - Alloy 5083 KW - Alloy 6082 KW - Al Ti5B1 PY - 2013 SN - 978-1-62708-998-2 SP - 98 EP - 107 PB - ASM international AN - OPUS4-27907 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Rhode, Michael A1 - Kromm, Arne A1 - Kannengießer, Thomas ED - Babu, S. S. ED - Bhadeshia, H.K. ED - Cross, C.E. ED - David, S.A. ED - DebRoy, T. ED - DuPont, J.N. ED - Koseki, T. ED - Liu, S. T1 - Residual stresses in multi-layer component welds T2 - 9th International conference on trends in welding research CY - Chicago, Illinois, USA DA - 2012-06-04 KW - Shrinkage restraint KW - Component welding KW - Submerged arc welding KW - Multi-run weld KW - Residual stresses KW - Reaction force KW - XRD KW - Large scale test PY - 2013 SN - 978-1-62708-998-2 SP - 48 EP - 54 PB - ASM international AN - OPUS4-27954 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfennig, Anja A1 - Linke, B. A1 - Schulze, S. A1 - Kranzmann, Axel T1 - Corrosion in pipe steels exposed to supercritical CO2 during carbon capture and storage CCS N2 - The CCS technique involves the compression of emission gasses in deep geological layers. To guarantee the safety of the site, CO2-corrosion of the injection pipe steels has to be given special attention when engineering CCS-sites. To get to know the corrosion behaviour samples of the heat treated steel 1.72252CrMo4, used for casing, and the stainless injection-pipe steel 1.4034 X46Cr13 were kept at T=60 °C and ambient pressure as well as p=100 bar for 700 h - 8000 h in a CC 2-saturated synthetic aquifer environment similar to possible geological on-shore CCS-sites in the northern German Basin. The isothermal corrosion behaviour obtained by mass gain of the steels in the gas phase, the liquid phase and the intermediate phase gives surface corrosion rates around 0.1 to 0.8 mm/year at ambient pressure and much lower about 0.02 to 0.2 mm/year at 100 bar where the CO 2 is in its supercritical state. Severe pit corrosion with pit heights around 4.5 mm are only located on the 42CrMo4 steel. Main phase of the continuous complicated multi-layered carbonate/oxide structure is siderite FeCO 3 in both types of steel. T2 - EUROCORR 2011 - Developing solutions for the global challenge CY - Stockholm, Sweden DA - 04.09.2011 KW - Steel KW - Pipeline KW - Corrosion KW - Carbonate layer KW - CCS KW - CO2-storage PY - 2011 SP - Paper 1044-1 EP - Paper 1044-8 AN - OPUS4-28008 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pfennig, Anja A1 - Linke, B. A1 - Schulze, S. A1 - Kranzmann, Axel T1 - Static and dynamic long term corrosion experiments in CCS-conditions N2 - Dealing with first corrosion screening experiments to predict the reliability and safety of Germanys first Carbon Capture and Storage site in the northern Bassin of Germany, northwest of the Capital Berlin, laboratory experiments have been established to simulate the particular conditions at T=60 °C, highly saline aquifer water similar to 'Stuttgart Aquifer', but only at ambient pressure. With mounting 2 independent full 2-grade titanium autoclave systems (running up to 250 bar and 300 °C) pressures up to p=100 bar are possible. In 2010 a specific corrosion chamber of 2-grade titanium working up to 100 °C, flowing aqui fer water with different gas mixtures was designed to fit to a high cycle fatigue testing machine. Long term fatigue experiments simulating fatigue crack growth under corrosive environments will soon start. These experiments may not only help engineering a CCS site, but results can be used to improve the maintenance of geothermal energy production sites, especially moved parts such as pumps and shafts. T2 - EUROCORR 2011 - Developing solutions for the global challenge CY - Stockholm, Sweden DA - 04.09.2011 KW - CO2 KW - Static corrosion KW - High cycle fatigue KW - Steel KW - CCS KW - CO2-storage KW - Corrosion PY - 2011 SP - 1 EP - 7 (Paper 1087) AN - OPUS4-28009 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Poli, Marco A1 - Grätz, Rainer A1 - Schröder, Volkmar ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Limitations of gas explosion venting due to accelerated flame propagation and elevated initial pressure N2 - Many industrial processes include a gas explosion hazard. If safety measures are not adequate to prevent a potentially explosive atmosphere or to avoid effective ignition sources in enclosures, at least the effects of an explosion can be limited e.g. by gas explosion venting systems. For the design of gas explosion venting systems for confinements only little guidance is given when considering the constructional boundary conditions or process conditions. For this reason conservative assumptions are prevalent in practice and in many cases the protective systems become significantly oversized. From safety perspective such safety margins in venting areas can lead to a critical acceleration of the pressure rise. Moreover, a gas explosion venting at turbulent conditions caused by over sizing or by obstacles rather leads to an under-sized system. The present investigation was focused especially on the influence of certain obstacles as well as the influence of elevated initial pressures on explosion venting behaviour of quiescent hydrogen, methane or ethylene in air. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Gas explosion venting KW - Turbulent combustion KW - Obstacles PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331111 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions VL - 31 SP - 661 EP - 666 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28582 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Liebner, Christian A1 - Heinrich, Sebastian A1 - Edeling, Florian A1 - Hieronymus, Hartmut A1 - Lange, T. A1 - Klemm, E. ED - Pierucci, S. ED - Klemes, J.J. ED - De Rademaeker, E. ED - Fabiano, B. ED - Buratti, S.S. T1 - Explosion initiation, propagation, and suppression inside a micro structured reactor N2 - The present contribution reports on specific aspects of safety engineering in heterogeneously catalysed oxidation reactions. Results for ethene-oxygen-mixtures in a continuous-flow micro reactor are reported related to the safety issues of the ethylene oxide process. Initial pressure is ranging from below 1 bar up to 10 bar at initial temperatures ranging from room temperature up to 673 K. Micro structured reactors offer an extended range of operating conditions. The key issue to be discussed in the present contribution is how to safely operate a micro reactor at conditions in conventional devices to be characterised as inside the explosion region. Within certain limits suppression of explosion inside a micro reactor can be achieved. This holds true for chain reactions as well as runaway reactions. Nevertheless it is not possible to safely operate micro structured reactors at any condition. Therefore, explosion propagation through a Micro structured reactor and initiation of gas phase explosions by hot spots inside the reactor were investigated. The investigation methods applied are subject to actual standardization. T2 - 14th International symposium on loss prevention and safety promotion in the process industries CY - Florence, Italy DA - 12.05.2013 KW - Micro reactor KW - Explosion KW - Safety PY - 2013 SN - 978-88-95608-22-8 DO - https://doi.org/10.3303/CET1331101 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 31 SP - 601 EP - 606 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milano AN - OPUS4-28583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schälike, Stefan A1 - Mishra, Kirti Bhushan A1 - Wehrstedt, Klaus-Dieter A1 - Schönbucher, A. T1 - Limiting distances for flame merging of multiple n-heptane and di-tert-butyl peroxide pool fires N2 - Experiments to determine the limiting distances for flame merging of multiple pool fires are presented. As model substances n-heptane and di-tert-butyl peroxide are used. Laboratory scale tests with a Diameter d = 6 cm and relative distances between the pools of 0.08 ≤ D/d ≤ 4 are described and complemented with field experiments with a diameter d = 1.5 m and relative distances between the pools of 0.17 ≤ D/d ≤ 1. Three regions for flame merging are observed and limiting distances are determined. A merging Region with the limiting distance Dmerg/d within which all flames merge together over the complete burning time. A transition region with the limiting distance Dtran/d within which some flames merge together while other flames are separated from each other. A separated region within which all flames are completely separated from each other. A correlation against the number of burning pools is presented to predict the limiting distances Dmerg/d und Dtran/d. T2 - ICheaP-11 - 11th International conference on chemical & process engineering CY - Milan, Italy DA - 02.06.2013 KW - Multiple fires KW - Flame merging KW - Mass burning rate KW - Limiting distances KW - Pool fire KW - Experimental study KW - Di-tert-butyl peroxide PY - 2013 SN - 978-88-95608-23-5 DO - https://doi.org/10.3303/CET1332021 SN - 1974-9791 N1 - Serientitel: Chemical engineering transactions – Series title: Chemical engineering transactions IS - 32 SP - 121 EP - 126 PB - AIDIC, Associazione Italiana di Ingegneria Chimica CY - Milan AN - OPUS4-28646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Steffen, Milan A1 - Schukar, Marcus ED - Jaroszewicz, L.R. T1 - Integration of Cu-coated single-mode optical fiber into carbon/PEEK composite for distributed structural health monitoring based on Rayleigh backscatter reflectometry N2 - In this paper a technique for integrating copper coated silica optical fibers into AS-4/PEEK composite for Structural Health Monitoring (SHM) is presented. The integration steps are described in detail. X-ray and microscopic images indicate a successfully integrated optical fiber which does not seem to affect the fiber/matrix distribution around it. Optical backscatter reflectometry shows losses of approximately 2dBm-1 along the integrated parts of the optical fiber due to temperature induced shrinkage of the composite. T2 - EWOFS 2013 - 5th European workshop on optical fibre sensors CY - Kraków, Poland DA - 19.05.2013 KW - SHM KW - Optical KW - Fiber KW - Rayleigh KW - OFDR KW - Composite KW - Copper coating PY - 2013 DO - https://doi.org/10.1117/12.2025280 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE IS - Paper 8794 - 181 SP - 879430-1 EP - 879430-6 AN - OPUS4-28627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schmigalla, S. A1 - Heyn, Andreas A1 - Wesling, V. A1 - Reiter, R. A1 - Echtermeyer, P. T1 - Investigation of the pitting corrosion behaviour of nickel based alloy claddings by evaluation of electrochemical noise measurements N2 - Claddings of different nickel based alloys were generated on a mild Steel (S235JR) and a stainless steel type 304 by Cold Metal Transfer (CMT). This welding procedure possesses a low degree of mixing between the Substrate and cladding material. Thus it improves the corrosion behaviour of the claddings. The aim of our investigations was to examine the effect of the welding parameters: energy per unit length, shielding gas and finishing surface treatment on the pitting corrosion behaviour of the claddings. However, under Standard test conditions nickel based alloys are often resistant to pitting corrosion. Moreover these test methods are inaccurate and require a large period of time resulting from the iterative progress to determine the critical pitting temperature (CPT). A potentiostatic test method was modified using a high concentrated CaCI2-solution and a conventional three electrode measuring cell. The pitting corrosion behaviour is calculated from current noise charges. During the test the course of corrosion is detected online by the evaluation of electrochemical noise Signals while a continuous increase of temperature by a defined heating rate is realised. Thus a critical pitting temperature can be estimated by only one attempt. Furthermore the deviation of the measured CPT is very low compared to Standard tests using gravimetrical and microscopic evaluation. That enables to figure out the influence of the welding parameters in an exact way. T2 - EUROCORR 2011 - Developing solutions for the global challenge CY - Stockholm, Sweden DA - 04.09.2011 KW - Nickelbasislegierung KW - Plattieren KW - Schweißverfahren KW - Cold metal transfer KW - Korrosionsprüfung KW - Elektrochemie KW - Elektrochemisches Rauschen PY - 2011 SP - 1 EP - 9 AN - OPUS4-24565 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Niebergall, Ute T1 - Comparison of the material parameters of polyethylene grades with the test performance behaviour of packagings for the transport of dangerous goods in dependence on the pre-storage time with 55% nitric acid N2 - The material parameters melt flow rate MFR, density D, notched impact strength N.I.S. at -30 °C, stress crack resistance FNCT and resistance to oxidative degradation Ox (determined by the increase of MFR) have been selected for a comparison of polyethylene grades for one design type in the “European Standard EN 15507 - Transport packaging for dangerous goods - Comparative material testing of polyethylene grades”. The parameters have a systematic relationship with design type tests. The notched impact strength at -30 °C and the resistance to oxidative degradation of polyethylene grades determined with test specimens of compression moulded sheets are directly comparable with drop tests at -18 °C of design types produced of these grades after pre-storage with 55 % nitric acid for 21 days at 40 °C. The impact of the pre-storage time of jerricans with 55 % nitric acid at 40 °C and 23 °C on the marginal drop heights in drop tests at -18 °C, on the MFR and on the tensile properties tensile strength, breaking elongation and the elastic modulus were investigated. Packaging design types (jerricans) made of three polyethylene grades from different producers were pre-stored with 55 % nitric acid for 21,42 and 84 days at 40 °C as well as for six months at 23 °C. The MFR and tensile properties of test specimens taken from the design type side walls as well as the marginal drop heights of the jerricans in drop tests at -18 °C were determined. The values of the notched impact strength at -30 °C of polyethylene grades are not comparable with the marginal drop heights determined in drop tests at -18 °C. The oxidative damaging impact of nitric acid has a greater effect on the grade with lower resistance to oxidative degradation by reducing more significantly the marginal drop heights with increasing pre-storage time. Pre-damage with 55 % nitric acid for 21 days at 40 °C, as recommended in ISO 16101 and EN 15507 caused an increase in the marginal drop heights of most design types in drop tests when compared with design types without pre-damage. The test results demonstrated clearly that pre-storage of the jerricans for six months at 23 °C caused a higher increase in the MFR and lower marginal drop heights of the jerricans in drop tests at -18 °C compared with pre-storage of the jerricans for 21 days at40 °C. The mechanical properties change as a result of diffusion of nitric acid into the polyethylene grades and the reaction of the nitric acid with the polymers. The percentage decrease and increase in the tensile strength, breaking elongation and elasticity modulus of test specimens taken from the design type side walls after different pre-storage times were only partly comparable with the marginal drop heights in drop tests at -18 °C. T2 - EUROCORR 2011 - Developing solutions for the global challenge CY - Stockholm, Sweden DA - 04.09.2011. KW - Gefahrgutverpackungen KW - Polyethylenformstoffe KW - Baumusterprüfungen KW - Nachweis der chemischen Verträglichkeit KW - Oxidativer Abbau PY - 2011 SP - 1 EP - 12 AN - OPUS4-24346 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Kusche, Nadine T1 - Calibration facility for quality certification of surface-attached fiber optic and electrical strain sensors N2 - Strain measurement in structures witli the purpose of long-term structurai health inonitoring must provide reliable inforination about the structure’s behavior over the whole period of use. The user must be sure that installed sensors are validated and work to the utmost satisfactiou. For this purpose, sensor Systems are tested using special facilities. Bccause it is not easy to characterize the strain transfer quality from the host structure into surface-applied strain sensors, a unique testing facility has been developed. Originally developed for fiber Bragg grating based sensors, the KALFOS facility (= calibration of fiber optic sensors) can also be used for electrical strain sensors. Calibration ineasurements are referenced by unbinsed Digital Image Correlation (D1C) and Electronic Speckle Pattern Interferometer (ESPI) methods. The strain transfer behavior can experimentally be analyzed and investigated under combined thermal and mechanical loading conditions and allows revealing wealuiesses in couimonly used attachment methodologies. The deformation of all members (particularly the coating/substrate - adhesive combination) in the sensing area is physically independently gained and recorded. Results achievcd allow precise description of the strain transfer function, Validation of the longterm strain sensor characteristics, matching of specific measurement requirements with environmental conditions, and, moreover, the verification of Standards for use of strain sensors. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.10.2011 KW - Fibre optic sensors KW - Structural health monitoring KW - Validation KW - Strain sensor KW - Surface application reliability PY - 2011 SN - 978-1-4244-9288-6 DO - https://doi.org/10.1109/ICSENS.2011.6127253 SP - 1337 EP - 1340 AN - OPUS4-24655 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Habel, Wolfgang A1 - Schukar, Vivien A1 - Tkachenko, Viktoriya T1 - How do application-related issues influence the reliability of fiber optic strain measurements? N2 - Fibre optic strain sensors are increasingly used and sensor systems are provided with specifications. Even if the performance is well specified, the strain characteristics of the sensor, strain transfer factor, mechanical stability under thermal influences, the performance of applied strain sensors can seriously differ from virgin sensor's the performance. The contribution will focus on issues that can deteriorate the sensor function or reduce the reliability of measurement results. Aspects are considered how to come to reliable strain measurements and how to validate strain measurements of applied sensors. Related to this topic, European activities like the recently started European COST TD1001 action, called (OfSeSa) will be presented. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.11.2011 KW - Fibre optic sensors KW - Structural health monitoring KW - Validation KW - Strain sensor KW - Surface application reliability PY - 2011 SN - 978-1-4244-9288-6 SP - 947 EP - 950 AN - OPUS4-24656 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Helm, C. A1 - Eichler, Thorsten A1 - Raupach, M. A1 - Isecke, Bernd T1 - Time dependency of current and potential distribution during the cathodic protection of RC structures N2 - Cathodic protection (CP) is a common method for rehabilitation of reinforced concrete structures suffering from Chloride induced corrosion. A sufficient protection of the corroding rebar can be ensured by use of several protection criteria. The use of these assessment criteria, in particular the so called 100 mV-criterion, can lead to erroneous resuits for certain unconventional arrangements of rebar and cp anode. Therefore a joint research project of the Institute for Building Materials Research, RWTH-Aachen University, Germany, (ibac) and the Federal Institute for Materials Research and Testing, Berlin, Germany, (BAM) has been set up to determine the applicability of CP under arbitrary geometrical conditions. A special focus was set on the applicability of surface applied anode Systems for protection of the reinforcement of structures opposite to the accessible side (e.g. outer side of tunnel Shell, Bridge deck protected from inside a box girder) In this paper, the impact of the time dependent changes of the Polarisation behaviour of the rebar on the current and potential distribution is shown by means of parametric studies using the FEM method. T2 - EUROCORR 2011 - Developing solutions for the global challenge CY - Stockholm, Sweden DA - 04.09.2011 KW - Cathodic protection KW - Long time effects of cathodic polarisation KW - FEM-modelling KW - Steel in concrete PY - 2011 SP - 1 EP - 11 AN - OPUS4-25326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wosniok, Aleksander A1 - Krebber, Katerina T1 - Simultaneous measurement of temperature and strain distribution using Brillouin scattering in dispersion-shifted fibers N2 - We studied Brillouin gain spectrum characteristics in dispersion-shifted fibers having compound GeO2-doping compositions in the fiber core to realize simultaneous measurement of distributed strain and temperature. Due to various dopant concentration alongside the radius of tested nonzero dispersion-shifted fibers several multiple Brillouin scattering resonances were observed in the stimulated Brillouin spectra arose through backscattering on higher acoustic modes which propagated along the fiber axis. As a result of the varying acoustic velocities, the Brillouin resonance peaks featured different temperature coefficients which can be used to accomplish the simultaneous measurement of fiber strain and temperature. We presented our first measurement results for NZDS Fujikura and LEAF Corning fiber and discussed the superior sensory suitability of the former fiber types. T2 - IEEE Sensors 2011 conference CY - Limerick, Ireland DA - 28.10.2011 KW - Fiber optic sensor KW - Spatial distributed sensor KW - Brillouin gain spectrum (BGS) KW - Nonzero dispersion-shifted fiber (NZDSF) KW - Brillouin sensor KW - BOTDA KW - BOFDA PY - 2011 SN - 978-1-4244-9288-6 SP - 1476 EP - 1479 AN - OPUS4-24828 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ewert, Uwe A1 - Heyne, Klara A1 - Zscherpel, Uwe A1 - Jechow, Mirko A1 - Bavendiek, K. ED - Thompson, D.O. ED - Chimenti, D.E. T1 - Optimum exposure conditions for computed radiography depending on fixed pattern noise and efficiency of imaging plate-scanner systems N2 - The presently active standards on Computed Radiography (CR) need a major revision. It was observed by many users that the image quality for class B of EN 14784-2 is not achievable under the same exposure conditions as used for film exposure. A mathematical model was developed and tested, which allows the calculation of the image quality, proven by image quality indicators (IQI), depending on the fixed pattern noise and the efficiency of the used imaging plate (IP) scanner system. All tested IP scanner systems provide a fixed correlation between the measured signal/noise ratio (SNR) and the grey values in the digital images. The maximum achievable SNRmax depends on the fixed pattern noise of the plate (high dose limit). Depending on the exposure dose an optimum visibility of IQIs can be predicted by calculation and measured considering the attenuation coefficient for calculation of the contrast/noise ratio (CNR). The diameter of the just visible wire is proportional to 1/sqrt(CNR). The optimum tube voltage for best visibility of IQIs and maximum CNR depend on the exposure dose. The optimum tube voltage for best visibility is achieved only at exposures with high dose. A dose dependant optimal tube voltage was not observed for film radiography. T2 - 37th Annual Review of Progress in Quantitative Nondestructive Evaluation CY - San Diego, CA, USA DA - 18.07.2010 KW - Computed radiography KW - Computed radiology KW - Non destructive testing KW - Image quality KW - Signal-to-noise ratio KW - Contrast-to-noise ratio KW - Imaging plates KW - Optimum tube voltage KW - Standards PY - 2011 SN - 978-0-7354-0888-3 DO - https://doi.org/10.1063/1.3591892 SN - 0743-0760 SN - 0094-243X N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings IS - 1335 SP - 493 EP - 500 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-27540 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kolkoori, Sanjeevareddy A1 - Shokouhi, Parisa A1 - Höhne, Christian A1 - Rahman, Mehbub-Ur A1 - Kreutzbruck, Marc A1 - Prager, Jens T1 - A comparative study of ray tracing and CIVA simulation for ultrasonic examination of anisotropic inhomogeneous austenitic welds N2 - Ultrasonic examination of anisotropic inhomogeneous austenitic welds is challenging, because of the columnar grain structure of the weld leads to beam skewing and splitting. Modeling tools play an important role in understanding the ultrasound field propagation and optimization of experimental parameters during the ultrasonic testing of austenitic welds as well as the interpretation of the test results. In this contribution, an efficient theoretical model based on the ray tracing concepts is developed to calculate the ultrasonic fields in inhomogeneous austenitic welds quantitatively. The developed model determines the ultrasound fields by taking into account the directivity of the ray source, the inhomogenity of the weld as well as ray transmission coefficients. Directivity of the ray source in columnar grained austenitic materials (including layback orientation) is obtained in three dimensions based on Lamb's reciprocity theorem. Ray energy reflection and transmission coefficients at an interface between two general columnar grained austenitic materials are calculated in three dimensions. The ray tracing model predictions on inhomogeneous austenitic weld material are compared against those from CIVA, a commercial non-destructive modeling and simulation tool. The ultrasonic modeling tools in CIVA are based on semi-analytical solutions. For beam propagation simulation, a so-called 'pencil method' is used, which involves modeling the probe as a set of individual source points, each radiating 'a bundle' of diverging rays into the medium and integrating those elementary contributions. Inhomogenity in the weld region is approximated by mapping the grain orientations on weld macrograph. Simulation results for ultrasonic field profiles for an austenitic weld are shown to be in good agreement with the corresponding experimental results. T2 - 39th Annual review of progress in quantitative nondestructive evaluation CY - Denver, Colorado, USA DA - 15.07.2012 KW - Crystal microstructure KW - Ray tracing KW - Ultrasonic materials testing KW - Ultrasonic propagation KW - Ultrasonic reflection KW - Ultrasonic transmission KW - Welds PY - 2013 SN - 978-0-7354-1129-6 DO - https://doi.org/10.1063/1.4789158 SN - 0094-243X SN - 1551-7616 N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings VL - 1511 SP - 1043 EP - 1050 PB - AIP Publishing AN - OPUS4-27736 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bartholmai, Matthias A1 - Köppe, Enrico A1 - Prager, Jens ED - Boller, C. T1 - Early damage detection of structural defects using guided waves N2 - Limited access to the object of relevance is often an essential problem in testing routines, e.g. for non-destructive testing of industry facilities or components of means of transportation. The presented project is about the development of a non-destructive testing method for application over great distances (up to 100 m). The method is based on directed excitation and measuring of Lamb waves (guided waves). It enables an effective differentiation of structural and defective indications as well as a classification of different defect types. The advantage of guided waves is the ability of propagation over great distances. This offers innovative possibilities for the investigation of large or difficult to access constructions. The testing method can be helpful in a broad variety of applications. It is useable for the characterization of plane or cylindrical, thin-walled surfaces of metal or fiber laminated materials. Particularly the investigation of aircraft wings and other aerospace components as well as the investigation of pipelines are addressed fields of application. T2 - EWSHM'12 - 6th European workshop on structural health monitoring 2012 CY - Dresden, Germany DA - 03.07.2012 KW - Lamb-waves KW - Ultrasound KW - Non-destructive evaluation KW - Early-damage-detection KW - Structural health monitoring PY - 2012 SN - 978-3-940283-41-2 VL - 2 SP - 1471 EP - 1478 CY - Berlin AN - OPUS4-26240 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kannengießer, Thomas A1 - Dabah, Eitan ED - Marquis, F. T1 - Energy dispersive synchrotron diffraction for in-situ analyses of hydrogen behavior in steels N2 - The extent of hydrogen embrittlement phenomenon is dependent on the interaction of hydrogen with the material i.e. diffusion behavior, lattice distortions, phase transformations and residual stresses developments. For the better understanding of the hydrogen interaction with the metal, possibilities of performing in-situ observations of the mentioned factors has to be accomplished. The EDDI (Energy Dispersive Diffraction) beamline at the BESSY II facility in Berlin provides this possibility and was used in order to investigate the aspects of this phenomenon in in-situ scale. The energy dispersive method entails a synchrotron X-ray white beam with a wide energy range (20–120 keV) which allows a fixed position of the sample and the detector, and combined with the high photons flux it allows a very short measurement time for obtaining a full scale X-Ray Diffraction patterns. In this contribution, the successful usage of high energy X-rays, applied for the first time for hydrogen behavior observations, provided the ability for evaluating in-situ the hydrogen diffusion behavior and the hydrogen interaction with stresses fields in the material. Steel samples were charged with hydrogen and examined by Synchrotron radiation. Two different methods were used in this research; the first is diffusible hydrogen concentration evaluation extracted from the lattice distortions, i.e. changes of the lattice parameter. The second is calculation of the residual stresses present in the sample and the interaction of hydrogen with them, using the known sin2ψ method. T2 - PRICM-8 - 8th Pacific rim international congress on advanced materials and processing CY - Waikoloa, Hawaii, USA DA - 04.08.2013 KW - Hydrogen embrittlement KW - Energy dispersive diffraction KW - Hydrogen diffusion KW - Residual stresses PY - 2013 SP - 3481 EP - 3487 AN - OPUS4-28975 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lenke, Karoline A1 - Hentschel, Yvonne A1 - Trappe, Volker T1 - Multiaxially loaded short fibre polyamide: a contribution to non-destructive evaluation of micro cracking and damage evolution N2 - Short fibre reinforced thermoplastics are increasingly used in automotive applications because of their potential for light weight design and cost efficient manufacturing by injection moulding. The fibre orientation, tuneable in the production process, defines the degree of anisotropy which causes different damage behaviour depending on the multiaxial stress state. Therefore, the multiaxial damage behaviour, based on micro cracking, is analysed by combining mechanical loading tests and non-destructive X-ray refractometry. T2 - ICCM19 - 19th International conference on composite materials CY - Montreal, Canada DA - 28.07.2013 KW - Short fiber reinforced composites KW - Multiaxial loading KW - Non-destructive testing KW - X-ray refraction KW - Damage mechanics PY - 2013 N1 - Geburtsname von Lenke, Karoline: Metzkes, K. - Birth name of Lenke, Karoline: Metzkes, K. SP - 5725 EP - 5733 AN - OPUS4-29004 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wosniok, Aleksander A1 - Mizuno, Y. A1 - Krebber, Katerina A1 - Nakamura, K. ED - Jaroszewicz, L.R. T1 - L-BOFDA: a new sensor technique for distributed Brillouin sensing N2 - We propose a new scheme of Brillouin optical frequency-domain analysis (BOFDA) for distributed fiber-optic strain and temperature sensing, named linear-configured BOFDA (L-BOFDA). In conventional loop-configured BOFDA, light injection into both ends of a fiber under test (FUT) is needed for counter-propagation of pump and probe waves. In contrast, in L-BOFDA, pump and probe waves are injected into the same end of an FUT, and the probe wave Fresnelreflected (or mirror-reflected) at the other end of the FUT is exploited; thus, one-end access is feasible. We show proof-of-concept results of distributed strain measurement in a silica single-mode fiber with L-BOFDA, and discuss the signal-to-noise ratio degradation and the benefit in developing distributed Brillouin sensors based on polymer optical fibers. T2 - EWOFS 2013 - 5th European workshop on optical fibre sensors CY - Kraków, Poland DA - 19.05.2013 KW - Brillouin optical frequency-domain analysis (BOFDA) KW - L-BOFDA KW - Optical fiber sensing KW - Distributed strain measurement KW - Stimulated Brillouin scattering KW - Polymer optical fiber PY - 2013 DO - https://doi.org/10.1117/12.2025378 SN - 0277-786X N1 - Serientitel: Proceedings of SPIE – Series title: Proceedings of SPIE VL - 8794 IS - Paper 8794 - 181 SP - 879431-1 EP - 879431-4 AN - OPUS4-28961 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholz, Christian A1 - Wäsche, Rolf T1 - Stick-slip and wear behavior of ceramic and polymer materials under reciprocating sliding conditions N2 - In many technical applications not only the actual friction coefficient is of importance, but rather the constancy relevant for the functionality. Due to inconstant ffiction values, positioning processes can be substantially influenced as well as vibrations can be induced. The appearance of this tribological effect, named stick-slip, depends on different factors such as sliding speed, relative humidity and ambient temperature occurring primarily after long operating periods. Beside ambient conditions the choice of materials in contact is the main influencing factor of an inconstant coefficient of friction during operating. Certain polymers are well known for their stick-slip tendencies in technical applications. These are on the one hand different modifications of PTFE (polytetrafluoroethylene) reinforced with glass fibers, bronze or graphite and on the other hand thermoplastics such as PE (polyester) or Pf (polyimide). The difference between static and dynamic values of the ffiction force is decisive for stick-slip phenomena. Furthermore, the stick-slip tendency of polymers strongly depends on the elastic material properties. Main softening material areas, which can be found in the contact, represent particularly vulnerable areas. The high friction value in the contact area decreases in most cases by increasing sliding speeds. However, beside polymers ceramic materials can also offer tendencies to stick-slip motion. Klaffke et al. already investigated the influence of ceramic materials on the stick-slip behavior in. T2 - WTC 2013 - 5th World tribology congress CY - Torino, Italy DA - 08.09.2013 KW - Stick-slip KW - Sliding speed KW - Polymers KW - Ceramics KW - Humidity PY - 2013 SP - 1 EP - 4 AN - OPUS4-29091 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scholz, Christian A1 - Woydt, Mathias T1 - The influence of high toughness silicon steels on applications demanding low friction and high load carrying capacity N2 - Highly concentrated or loaded contacts in powertrain and gear applications offer significant weight savings in C02 emissions. Today, thin film coatings, alternative base oils and new additives are populär as working fields and strategies of OEMs to realize low friction tribosystems. Especially the automotive industry anticipates environmental and performance benefits in applying light-weight construction of mechanical parts, for instance in gears and engines. Light-weight strategies increase the contact stresses above 2.14 GPa (or FZG load stage 14) due to the reduction of component sizes. These demands directly raise questions about the suitability of the most promising technical solution. Alternative steels with improved mechanical properties, i.e. toughness values, which offer low coefficients of friction, optimal resistance to high contact pressure and potential to apply low friction surface coatings representing a valid alternative to conventional gear steels. Traditional bearing and gear steels, such as 100Cr6 (SAE E52100) or 16MnCr5 (1.7131) have reached their mechanical limits at contact pressures above FZG load stage 14. T2 - WTC 2013 - 5th World tribology congress CY - Torino, Italy DA - 08.09.2013 KW - Slip-rolling KW - Silicon steel KW - DLC KW - High load KW - Gear steel PY - 2013 SP - 1 EP - 4 AN - OPUS4-29092 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Greenhalgh, E.S. A1 - Ankersen, J. A1 - Asp, L. E. A1 - Bismarck, A. A1 - Fontana, Q.P.V. A1 - Houlle, M. A1 - Kalinka, Gerhard A1 - Kucernak, A. A1 - Mistry, M. A1 - Nguyen, S. A1 - Qian, H. A1 - Shaffer, M.S.P. A1 - Shirshova, N. A1 - Steinke, J.H.G. A1 - Wienrich, Malte T1 - Mechanical and microstructural characterisation of multifunctional structural power composites N2 - Although the inherent anisotropy of polymer composites has presented daunting technical challenges, these materials now offer engineers considerable opportunities for efficient structural design. More recently, the advent of multifunctional composites which can fulfill more than one role within a system has attracted considerable interest, providing designers with exciting opportunities to innovate. Of particular interest here are structural power composites, which simultaneously carry mechanical load whilst storing/delivering electrical energy. Although the development of these composites is highly challenging, often with conflicting constituent requirements, the STORAGE consortium has had considerable success in the development of these materials for automotive applications. The focus of this paper is structural supercapacitors, the basic architecture of a single cell of which is shown in Fig. 1. This entails two carbon fibre woven lamina (electrodes) which sandwich a glass fibre woven lamina (separator), all of which is embedded within a multifunctional matrix (electrolyte). This architecture has been the focus of the research to date, leading to components such as that shown in Fig.1 having been fabricated. This paper reports on the mechanical properties and microstructures of the different reinforcement and matrix combinations for structural supercapacitors. T2 - ICCM19 - 19th International conference on composite materials CY - Montreal, Canada DA - 28.07.2013 KW - Structural electrolyte KW - Multifunctional supercapacitor KW - Fractography KW - Ionic conductivity KW - Mechanical properties PY - 2013 SP - 2228 EP - 2237 AN - OPUS4-29272 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shirshova, N. A1 - Bismarck, A. A1 - Carreyette, S. A1 - Greenhalgh, E.S. A1 - Johansson, P. A1 - Marczewski, M.J. A1 - Jacobsson, P. A1 - Kalinka, Gerhard A1 - Shaffer, M.S.P. A1 - Wienrich, Malte A1 - Steinke, J.H.G. T1 - Correlations between mechanical properties and ionic conduction of structural electrolytes with bicontinuous morphologies N2 - Electrolyte systems that can carry mechanical load while allowing for high levels of ionic conductivity are an important prerequisite for structural power storage devices. Introduction of structural power storage into the variety of consumer products will allow saving in weight and volume. Moreover, using a supercapacitor/battery system in hybrid electric vehicles (HEV), the supercapacitor part will extend the battery lifetime by protecting it from the high peak currents. To successfully produce structural power storage requires the development of multifunctional electrolytes where one has to simultaneously maximize mechanical properties and ionic conductivity. T2 - ICCM19 - 19th International conference on composite materials CY - Montreal, Canada DA - 28.07.2013 KW - Structural electrolyte KW - Multifunctional supercapacitor KW - Bicontinuous morphology KW - Epoxy resin KW - Ionic conductivity KW - Mechanical properties PY - 2013 SP - 72 EP - 79 AN - OPUS4-29273 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Österle, Werner A1 - Dmitriev, Andrey A1 - Kloß, Heinz T1 - Assessment of sliding friction of a nanostructured solid lubricant film by numerical simulation with the method of movable cellular automata (MCA) N2 - Tribofilms formed during dry sliding usually exhibit a nanocrystalline structure and complicated composition. In the present study, tribofilms consisting mainly of a solid lubricant, namely graphite nanoparticles, are considered. Systems providing such tribofilms are candidates for anti-friction applications. Since sliding action always leads to mixing of the materials at both sides of the tribological interface, it was of major interest to study the impact of different amounts of a hard constituent, SiC in the considered case, within the soft matrix systematically. Furthermore, the impact of normal pressure was considered. A mechanically mixed layer was observed for the whole range of normal pressures and SiC volume fractions. The calculated coefficient of friction decreased significantly with increasing thickness of this layer but was only marginally affected by SiC volume fraction, which is good news for anti-friction applications. T2 - WTC 2013 - 5th World tribology congress CY - Torino, Italy DA - 08.09.2013 KW - Friction KW - Third body film KW - Numerical simulation KW - Nanostructure PY - 2013 SP - 1 EP - 4 AN - OPUS4-29659 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wolf, Julia A1 - Milmann, Boris A1 - Helmerich, Rosemarie A1 - Köpp, Christian A1 - Mielentz, Frank A1 - Wiggenhauser, Herbert A1 - Kurz, J.H. A1 - Moryson, R.-M. A1 - Samokrutov, A. A1 - Alekhin, S. G. A1 - Alver, Ninel A1 - Sazak, H.-Ö. ED - Xu, Y. L. ED - Zhu, S. ED - Xia, Y. ED - Ni, Y.Q. ED - Law, S.S. ED - Yin, J. H. ED - Su, Z.Q. T1 - Ultrasound based monitoring system for concrete monolithic objects N2 - Ultrasound sensors should be embedded into concrete for monitoring concrete properties. These new longitudinal wave sensors with a center frequency of 60 kHz were examined regarding their suitability for ultrasonic measurements in concrete structures in terms of emission characteristics, sensitivity and frequency ränge. For the measurement of the radiation patterns, the sensors were embedded vertically and horizontally in concrete cylinders. The directivity pattern was measured using a laser vibrometer. The sensitivity of the sensor was determined in water using different sensors of the same type. It shows changes in the signal amplitude as well as variations in the frequency ränge for different transmitter-receiver combinations. The attenuation of the concrete affects the achievable resolution of the measurements and thus, the maximum possible spacing of the sensors within a concrete element. Experimental tests helped optimizing the distances with respect to the required resolution and the effort of embedding the sensors. The signal attenuation in the concrete was measured in the frequency ränge of 60 kHz in response to various degrees of reinforcement and grain size. For this purpose, the sensors were cast at different distances in the specimens studied. The recorded Signals were evaluated for their amplitude and frequency spectrum. T2 - SHMII-6 - 6th International conference on structural health monitoring of intelligent infrastructure CY - Hong Kong, China DA - 09.12.2013 KW - Ultrasound KW - Concrete KW - Monitoring system KW - Ultrasonic network KW - Embedded sensor PY - 2013 SN - 978-962-367-768-4 SP - 1 EP - 6 AN - OPUS4-29642 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Quercetti, Thomas A1 - Musolff, André A1 - Müller, Karsten T1 - Instrumented measurements on radioactive waste disposal containers during experimental drop testing N2 - In context with disposal container safety assessment of containers for radioactive waste the German Federal Institute for Materials Research and Testing (BAM) performed numerous drop tests in the last years. The tests were accompanied by extensive and various measurement techniques especially by instrumented measurements with strain gages and accelerometers. The instrumentation of a specimen is an important tool to evaluate its mechanical behavior during impact. Test results as deceleration-time and strain-time functions constitute a main basis for the validation of assumptions in the safety analysis and for the evaluation of calculations based on finite-element methods. Strain gauges are useful to determine the time dependent magnitude of any deformation and the associated stresses. Accelerometers are widely used for the measuring of motion i.e. speed or the displacement of the rigid cask body, vibration and shock events. In addition high-speed video technique can be used to visualize and analyze the kinematical impact scenario by motion analysis. The paper describes some selected aspects on instrumented measurements and motion analysis in context with low level radioactive waste (LLW) container drop testing T2 - ICEM 2011 - 14th International Conference on environmental remediation and radioactive waste management CY - Reims, France DA - 25.09.2011 KW - Drop test KW - Radioactive KW - Disposal container KW - Instrumented measurements PY - 2011 DO - https://doi.org/10.1115/ICEM2011-59142 SP - 929 EP - 938 AN - OPUS4-27044 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jaenisch, Gerd-Rüdiger A1 - Deresch, Andreas A1 - Bellon, Carsten A1 - Ewert, Uwe A1 - Przybilla, Waldemar ED - Thompson, D.O. ED - Chimenti, D.E. T1 - Measurement and modeling of scatter ratios at high energies N2 - Determining scatter ratios at high energies (> ~ 1MeV) presents challenges not immediately obvious from measurements at conventional X-ray energies. This includes reduced attenuation even in heavy elements as well as a stronger forward bias of scattering. In order to check the reliability of different measurement setups with regard to material thicknesses, distances, and collimation, attenuation and scattering were separately simulated using a Monte Carlo model. The simulation results help in understanding the sources of radiation scattered into the detection area, thereby aiding in eliminating undesired contributions. T2 - 37th Annual Review of Progress in Quantitative Nondestructive Evaluation CY - San Diego, CA, USA DA - 18.07.2010 KW - Radiography KW - Optimisation KW - X-ray detection KW - Simulation KW - High energy KW - Co-60 KW - Modeling KW - Scatter PY - 2011 SN - 978-0-7354-0888-3 DO - https://doi.org/10.1063/1.3591895 SN - 0743-0760 SN - 0094-243X N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings IS - 1335 SP - 517 EP - 524 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-25358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Böllinghaus, Thomas A1 - Mente, Tobias T1 - Vermeidung von Rissen beim Schweissen von Rohrleitungen N2 - Schadensfälle in den letzten zehn Jahren mit teilweise katastrophalen Folgen belegen, dass der Vermeidung von Rissen beim Schweißen von Rohrleitungen besondere Aufmerksamkeit zu schenken ist. In der Analyse solcher Schäden ist zu unterscheiden, ob die Risse bereits während oder kurz nach der schweißtechnischen Fertigung der Rohrkomponenten oder während des anschließenden Betriebes entstanden sind. Im vorliegenden Beitrag wird sich vor allem auf die Vermeidung einer Heiß- und Kaltrissbildung beim Schweißen von Rohrleitungen konzentriert und es werden weitere Forschungsperspektiven abgeleitet. T2 - DVM-Tag 2011 - Bauteilzuverlässigkeit - Schäden und ihre Vermeidung CY - Berlin, Germany DA - 04.05.2011 KW - Rissvermeidung KW - Heißrissbildung KW - Wasserstoffunterstützte Kaltrissbildung (HACC) KW - Pipelineschweißungen PY - 2011 SN - 0946-5987 N1 - Serientitel: DVM-Bericht – Series title: DVM-Bericht IS - 678 SP - 81 EP - 90 AN - OPUS4-26113 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg A1 - von Chrzanowski, Lars A1 - Fratzscher, Daniel A1 - Ewert, Uwe ED - Thompson, D. O. ED - Chimenti, D. E. T1 - Spectral and spatial nondestructive examination of dielectric materials with THz time domain spectroscopy N2 - A time domain spectrometer T-ray 2000® operating in the range of 0.2-2 THz was used for Time of Flight measurements. A series of ethanol water mixtures from 10% to 90% were produced subsequently filled in polystyrene cells and analyzed in the T-ray 2000 TDS system in the reflection mode. The reflectivity of the material liquid interface is strongly influenced by the ethanol concentration in water. The reciprocal reflection coefficient of the material liquid interface was found to be a useful discriminating feature for further Probably of Detection calculations which can be used for the performance evaluation of potential THz bottle scanners. THz pulse echo (PE) measurements were performed in comparison to the established ultra sound PE technique for flaw detection of plastics. Synthetic aperture reconstructions were applied for simulated data to reconstruct the flaw shape. The results were compared with B-scan images of a high density polyethylene (HDPE) test cylinder. Existing restrictions on the quality of the back projected images and limits of the existing model are discussed in detail. T2 - 38th Annual Review of Progress in Quantitative Nondestructive Evaluation CY - Burlington, VT, USA DA - 17.07.2011 KW - Terahertz time domain spectroscopy KW - Time of flight diffraction KW - Non destructive testing KW - Polymers KW - Probability of detection KW - Thz Tomography PY - 2012 SN - 978-0-7354-1013-8 DO - https://doi.org/10.1063/1.4716279 SN - 0743-0760 SN - 0094-243X N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings VL - 31A IS - 1430 SP - 573 EP - 580 PB - American Institute of Physics CY - Melville, NY AN - OPUS4-26103 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gaal, Mate A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Beck, Uwe A1 - Weise, Matthias A1 - Bovtun, Viktor Petrovic A1 - Brekow, Gerhard A1 - Kreutzbruck, Marc T1 - Parameter reproducibility of polypropylene ferroelectret transducers for air-coupled ultrasonic testing N2 - The extremely low acoustic impedance of polypropylene ferroelectret combined with its piezoelectric properties makes this material suitable for construction of aircoupled ultrasonic transducers for non-destructive testing. For the fabrication of transducers with a stable quality, the reproducibility of their key parameters is of interest. The reproducibility was evaluated by means of (i) impedance spectroscopy and (ii) pulse-echo measurements. (i) Impedance spectroscopy was applied to identify the resonance frequency, the coupling factor and the acoustic impedance of several nominally identical transducers. (ii) Pulse-echo measurements yielded the signal form of these transducers. The variation of the signal amplitude measured with pulseecho technique was about 10 dB. A part of this variation Comes from the deposition of transducer electrodes and another part from local variations of ferroelectret properties. The variation of the signal amplitude was caused by the observed variation of the coupling factor, which was also about 10 dB. The variation of the acoustic impedance was only about 1 dB, thus having no effect on the variation of the signal amplitude. These results indicate that the variability can be reduced by improving the control of electrode deposition and by optimizing the production technology affecting the reproducibility of material properties. T2 - 2011 IEEE International ultrasonics symposium (IUS) CY - Orlando, FL, USA DA - 18.10.2011 KW - Air-coupled ultrasonic transducers KW - Polypropylene ferroelectret KW - Reproducibility PY - 2011 IS - Abstract-ID 258 SP - 1 EP - 3 AN - OPUS4-26405 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reich, Franziska A1 - Otremba, Frank A1 - Würsig, Andreas T1 - Fail-safe? A study about the integrity of safety valves for tanks for dangerous goods N2 - In Europe, tanks designed on different safety philosophies are used for transporting one and the same liquid dangerous goods (Krautwurst, 2011). Owing to this circumstance, the BAM was commissioned by the BMVBS to conduct a research project designed to analyse and assess the equipment of tanks. Furthermore in these project were researched some failure mechanism of pressure relief devices (PRD). Based on the knowledge gained, possible solutions were worked out under safety-relevant aspects that would benefit tank transport by providing a lower hazard potential. Besides looking at the mode of operation and the construction of PRV, their blow-off characteristics and total flow rate are considered from a safety engineering point of view. Based on in-depth studies, a concept for and the further approach to examinations of the failure limits of PRD, especially of spring loaded relief valves, was developed and comprehensively described in the report “The use of safety devices, particularly safety valves, on transport containers” (Pötzsch, Reich, & Jochems, 2011). The purpose of this study was to investigate failure causes of safety valves by normal modes and accidental fire heat loads. A series of investigations for different influences using safety valves for tanks were obtained. Testing vibration modes and corrosion presents some design limits. Experimental study of a pressure vessel engulfing in fire identify significant design limits. The complete set of results provides direct information of fail-safe modes and discusses the usage. T2 - ASME 2013 International mechanical engineering congress and exposition CY - San Diego, CA, USA DA - 15.11.2013 KW - Safety valves KW - Transporttanks KW - Dangerous goods KW - Fire prooving KW - Response behavior PY - 2013 IS - IMECE2013-62204 SP - 1 EP - 5 AN - OPUS4-29717 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hamann, M. A1 - Kubowitz, P. A1 - Hofmann, Detlef ED - Xu, Y. L. ED - Zhu, S. ED - Xia, Y. ED - Ni, Y.Q. ED - Law, S.S. ED - Yin, J. H. ED - Su, Z.Q. T1 - Scale of intelligence in hybrid bridge structures - new aspects of monitoring by using fibre-optic sensors in timber elements N2 - In structural engineering timber is appreciated due to its low weight, its high aesthetic quality and because it is a renewable resource. The market share of timber structures and wood based hybrid structures will clearly increase over the next few years due to greater environmental awareness and a higher demand for sustainability. However, building with timber is marked by characteristics which lead to significant disadvantages in comparison wifh technical materials. For example, in outdoor areas Chemical and structural approaches offen lead to unsatisfactory and expensive Solutions with respect to durability. An idea is to make natural lumber a high-performance material which can be designed to meet the engineers’ demands conceming strength, stiffness, durability, shape, safety etc. These changes can affect the material itself, new technologies or a new approach to monitoring. Especially hybrids made of common timber products and technical textiles or enhanced timber products are high-capacitive and reach high bearing strengths with low material input and good durability. These hybrids are particularly qualified to use the advantages of wood and minimize the disadvantages. They can be used in different ways for load bearing structures, i.e. bridges. New construction types need monitoring to observe the stress and strains for which they were designed, and the structures’ behaviour as well as to guarantee required safety levels. The aim of successful usage of fibre optic measurement technology in timber elements was the development of a technology for measuring the lengthening in timber elements and wood based hybrid elements by using fibre optic sensors. The scientific and technical challenge was to develop an applicationtechnology for optical glass fibres in timber and densified veneer wood. In laboratory tests as well as with the erection of a footbridge and during in-situ tests it could be shown that the structurally integrated fibre optic sensor technology used is suitable for short and long term measurement. The developed embedment technology tums out to be practical and fit for good transfer of strain-values from timber to the modified sensor fibres. T2 - SHMII-6 - 6th International conference on structural health monitoring of intelligent infrastructure CY - Hong Kong, China DA - 09.12.2013 KW - Structural health monitoring KW - Structural engineering KW - Timber KW - Composites KW - Hybrid construction types KW - Fibre optic sensor technology KW - Sensor fibres PY - 2013 SN - 978-962-367-768-4 SP - 1 EP - 10 AN - OPUS4-29913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nöther, N. A1 - Wang, S. A1 - Wosniok, Aleksander A1 - Glötzl, R. A1 - Schneider-Glötzl, J. ED - Xu, Y. L. ED - Zhu, S. ED - Xia, Y. ED - Ni, Y.Q. ED - Law, S.S. ED - Yin, J. H. ED - Su, Z.Q. T1 - Distributed Brillouin sensing in optical fibers: Soil displacement monitoring using sensor-equipped geogrids N2 - This paper reports on the application of distributed Brillouin fiber optic sensing to the monitoring of geotechnical structures. The presented approach to Brillouin sensing offers an alternative to the common pulse-based measurements by using the frequency domain analysis. The focus of the research and field-testing work is to collect reliable structural health monitoring data from large-scale structures while preserving the System’s versatility in terms of being suitable for different application environments (soil structures, foundations, concrete construction works, pipelines etc.) and its robustness in being well functioning in harsh environments. Upon reviewing the presented application test, it is concluded that Brillouin frequency domain based monitoring, when applied to geotechnical structures, is capable of providing accurate strain readings representing deformations of the soil body, and reliable temperature readings for generating temperature profiles of the entire structure. An overview of the frequency domain analysis of Brillouin sensing and its digital implementation is given, along with the experiences and insights drawn from an open field test of sensor-equipped geogrid mats. T2 - SHMII-6 - 6th International conference on structural health monitoring of intelligent infrastructure CY - Hong Kong, China DA - 09.12.2013 KW - Structural health monitoring KW - Distributed sensing KW - Fiber-optic sensing KW - Brillouin sensing KW - Strain and temperature measurements KW - Sensor-equipped geosynthetics PY - 2013 SN - 978-962-367-768-4 SP - 290 EP - 295 AN - OPUS4-29914 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Landsberger, Petra A1 - Boenke, Viola A1 - Gorbushina, Anna A1 - Rodenacker, K. A1 - Pierce, B.F. A1 - Kratz, K. A1 - Lendlein, A. T1 - Bacterial attachment on poly[acrylonitrile-co-(2-methyl-2-propene-1-sulfonic acid)] surfaces N2 - The influence of material properties on bacterial attachment to surfaces needs to be understood when applying polymer-based biomaterials. Positively charged materials can kill adhered bacteria when the charge density is sufficiently high but such materials initially increase the adherence of some bacteria such as Escherichia coli. On the other hand, negatively charged materials have been shown to inhibit initial bacterial adhesion, but this effect has only been demonstrated in relatively few biomaterial classes and needs to be evaluated using additional systems. Gradients in surface charge can impact bacterial adhesion and this was tested in our experimental setup. Moreover, the evaluation of bacterial adhesion to biomaterials is required to assess their potential for biological applications. Here, we studied the bacterial adhesion of E. coli and Bacillus subtilis on the surfaces of acrylonitrile-based copolymer samples with different amounts of 2-methyl-2-propene-1-sulfonic acid sodium salt (NaMAS) comonomer. The content related to NaMAS based repeating units nNaMAS varied in the range from 0.9 to 1.5 mol%. We found a reduced colonized area of E. coli for NaMAS containing copolymers in comparison to pure PAN materials, whereby the bacterial colonization was similar for copolymers with different nNaMAS amounts. A different adhesion behavior was obtained for the second tested organism B. subtilis, where the implementation of negative charges into PAN did not change the overall adhesion pattern. Furthermore, it was observed that B. subtilis adhesion was significantly increased on copolymer samples that exhibited a more irregular surface roughness. T2 - MRS Spring meeting 2013 CY - San Francisco, CA, USA DA - 01.04.2013 KW - Biomaterial KW - Biological KW - Polymer PY - 2013 DO - https://doi.org/10.1557/opl.2013.832 VL - 1569 IS - MRSS13-1569-NN15-13.R1 SP - 1 EP - 6 AN - OPUS4-30161 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Mehdianpour, Milad ED - Gomes, J.F.S. ED - Meguid, S.A. T1 - Wind measurements along a high-voltage overhead transmission line in northern Germany N2 - The paper focuses on a recently launched project of wind measurements along a high voltage overhead transmission line. For reliable information on the actual horizontal distribution of the wind flow, 13 positions along two spans of an overhead electrical line of about 400 m length each are selected for wind measurements. Simultaneously, the structural response is measured at the towers. Preliminary analyses aim at the system identification of long span transmission lines exposed to gusty wind by derivation of a so called joint acceptance function which describes the admittance from wind velocity to the system's response. It can be shown that measured structural response can accurately be described using a statistical model which accounts for the irregularity of the wind as well as the structure’s behaviour. T2 - IRF 2013 - 4th International conference on integrity, reliability and failure CY - Funchal, Portugal DA - 23.06.2013 KW - Overhead transmission lines KW - Wind loading KW - Field measurements KW - Monitoring PY - 2013 SN - 978-972-8826-28-4 IS - Paper 3920 SP - 1 EP - 9 AN - OPUS4-28846 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marotzke, Christian A1 - Feldmann, Titus T1 - Fracture mechanics of composite plies on microscale N2 - The determination of the strength and the failure behaviour of fiber reinforced composites is a complex task. This is mainly due to the anisotropy and the inhomogeneiety of the material on the microscale. The strength or the fracture toughness of the interface between fiber and matrix is the key factor controlling the failure process on microscale, especially under loads transverse to the fiber axes. The ultimate failure of a laminate is a complex process consisting of a large number of different subprocesses. Due to its highly dynamic nature on one hand and the microscopical scale on the other it is not possible to observe the ultimate failure directly or even to analyse it theoretically. However, long before ultimate failure occurs a large number of elementary failure processes take place in a rather static manner or at least at low crack Propagation speed. T2 - ICCM19 - 19th International conference on composite materials CY - Montreal, Canada DA - 28.07.2013 KW - Fracture mechanics KW - Laminate KW - Interface KW - Debonding KW - Energy release rate PY - 2013 SP - 5354 EP - 5363 AN - OPUS4-28913 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Karsten A1 - Scheidemann, Robert A1 - Auster, Jürgen T1 - Mechanical testing of component size specimen under impact conditons N2 - For validation of structural integrity under normal and hypothetical accident conditions during transport and storage of radioactive material the Federal Institute for Materials Research and Testing (BAM) focuses its safety related scientific research on advanced mechanical safety assessment methods including simulation of high rate impact of model components and structures. A drop and crash test facility with an unyielding target and a load capacity of 1.200 kg was designed for materials testing of component size specimen under impact conditions at elevated and higher loading rates. The maximum drop height is 12 meters which enables impact velocities up to 15 m/s. An exactly falling test object or drop weight allows impact, bending, compression as well as crash and crush tests with maximum input energy of 118 kJ. An arresting unit has been developed to avoid multiple impacts during instrumented drop tests. The paper presents experimental techniques and examples of various measurement methods and advancements in order to assess assumption of materials and components behavior by definite displacement and stresses within mechanical testing. Instrumented drop weight tests are performed to complete materials data base and energy absorption of shock-absorbing materials and structures as well as to implement materials and structural parameters into FEA of reference structures. Furthermore, fracture mechanics parameters of thick walled DCI containers by means of dynamic bending tests are characterized by crack initiation and crack resistance behavior at the lowest operational temperature depending on the strain rate. T2 - PVP2013 - ASME 2013 Pressure vessels & piping division conference CY - Paris, France DA - 14.07.2013 KW - Component size KW - Impact test KW - Dynamic compression KW - J-integral PY - 2013 DO - https://doi.org/10.1115/PVP2013-98000 IS - PVP2013-98000 SP - 1 EP - 7 AN - OPUS4-28893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Patrick P. A1 - Schnürmacher, M. A1 - Bennetts, V.H. A1 - Lilienthal, A.J. A1 - Bartholmai, Matthias A1 - Schiller, J.H. T1 - A probabilistic gas patch path prediction approach for airborne gas ource localization in non-uniform wind fields N2 - In this paper, we show that a micro unmanned aerial vehicle (UAV) equipped with commercially available gas sensors can address environmental monitoring and gas source localization (GSL) tasks. To account for the challenges of gas sensing under real-world conditions, we present a probabilistic approach for GSL that is based on a particle filter (PF). Simulation and real-world experiments demonstrate the suitability of this algorithm for micro UAV platforms. T2 - ISOEN 2013 - 15th International symposium on olfaction and electronic nose CY - Deagu, South Korea DA - 02.07.2013 KW - Autonomous micro UAV KW - Chemical and wind sensing KW - Gas source localization KW - Particle filter PY - 2013 IS - Symposia / Applications of remote and local gas sensing ... SP - 15 EP - 16 AN - OPUS4-28878 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Gumenyuk, Andrey A1 - Petrovskiy, V.N. A1 - Rethmeier, Michael A1 - Shcheglov, Pavel A1 - Uspenskiy, S.A. T1 - Condensed metal particles influence during the high power fiber laser welding N2 - Different types of lasers are used nowadays for a number of technological Solutions, Modem high power solid-state lasers with high brightness of Radiation like Fiber or disc lasers find ever more applications in welding technology. Apart from the replacement of the CC>2-iasers traditionaHy used fcr these purposes, they provide new technological possibilities of metal treatment, such as using industrial robots and remote welding with high power laser radiation. The possibility of flexible optical fiber delivery of the radiation to any point gives a great technological advantage and permits welding processes to be realized with complicated weld seam geomelries and different positions using a minimum of additional fixtures. The short wavelength of the high power solid state lasers (1.07 ’m) causes another advantage. The coefflcient of inverse 170 Bremsstrahlung absorption from free electrons in plasma for such radiation is about 100 times lower than for the COi-iaser radiation. Owing to this fact, using the solid state lasers allows it to avoid a negative influence of the welding plume. However, a short wavelength can lead to another kind of laser Radiation attenuation, which is connected with the formation of a cloud consisting of small metal particles that absorb and scatter laser radiation. This cloud arises due to the condensation of hot metal vapor by flying out from the deep Penetration channel and broadening in relatively cold atmosphere over the metal Surface. Some theoretical and experimental approaches were made in advance in Order to estimate the influence of the Condensed particles on laser radiation and welding quality. In this paper a systematic study including the determination of the Cloud size and its dynamical characteristics is presented. The results were obtained within the scope of the first stage of the metal vapor condensation process Investigation during welding with high power fiber lasers. T2 - International Conference 'Lasers in Science, Technology, Medicine' CY - Moscow, Russia DA - 19.09.2011 PY - 2011 VL - 22 SP - 170 EP - 177 AN - OPUS4-29166 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Woydt, Mathias T1 - Tribological profile of binderless and cobalt bonded niobium carbide N2 - The tribological profile of alumina (99.7%) mated against rotating disks in two niobium Carbide (NbC) grades were determined in unidirectional sliding tests (0.1 m/s to 7.5 m/s; 22°C and 400°C) as well as in oscillation tests (f= 20 Hz, Ax= 0.2 mm, 2/50/98% rel. humidity, n= 1062 c* y*c *l es) under unlubricated (dry) conditions. In addition, the microstructure and mechanical properties of NbC were determined as well. The reason for testing hot-pressed NbC was to avoid side effects generated by sintering additives and/or second phases. The tribological data obtained were benchmarked with different ceramics, cermets and thermally sprayed coatings. NbC exhibited low wear rates under dry sliding associated with high load carrying capacity. The tribological profile established revealed a strong Position of NbC under tribological considerations and for closed tribo-systems against traditional references, such as WC, Cr3C2, (Ti,Mo)(C,N), etc.. T2 - Euro PM2013 Congress & Exhibition CY - Gothenburg, Sweden DA - 15.09.2013 KW - Sliding friction KW - Sliding wear KW - Oscillation KW - Ceramic KW - Coating KW - NbC KW - Cobalt PY - 2013 SN - 978-1-899072-40-8 SP - 1 EP - 7 AN - OPUS4-29141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weltschev, Margit A1 - Werner, Jan A1 - Heming, Frank A1 - Haufe, Manuela T1 - Compatibility of sealing materials with biodiesel, bioethanol-gasoline and biodiesel-heating oil blends N2 - Biofuels including ethanol and biodiesel (fatty acid methyl ester) represent an impor-tant renewable fuel alternative to petroleum-derived transport fuels. Increasing bio-fuel use would bring some benefits, such as a reduction in oil demands and green-house gas emissions, and an improvement in air quality. Materials compatibility is a major concern whenever the fuel composition is changed in a fuel system. The aim of this work is to study the interaction between sealing materials such as FKM (fluorocarbon rubber), EPDM (ethylene-propylene-diene rubber), CR (chloro-prene rubber), CSM (chlorosulfonated polyethylene), NBR (acrylonitrile-butadiene rubber), IIR (butyl rubber), VMQ (methyl-vinyl-silicone rubber) and FVMQ (methyl-fluoro-silicone rubber) and biofuels such as biodiesel, E85 (fuel with 85% ethanol) and B10 (heating oil with 10% biodiesel) at 70°C for 84 days. Experiments were con-ducted with tests specimens of theses elastomers to document the changes in the mass and tensile properties of these sealing materials according to ISO 1817. The exposure tests of the elastomers in E85 at 70°C showed that the weight gain caused by swelling of the test specimens was in the range of 3% to 12%. However, the weight gain of the fluorinated elastomers was at the lower end of this range. Tensile strength and breaking elongation decreased by 22% to 61% or 13% to 77%. The lowest decrease in the tensile properties was determined for FKM, EPDM und IIR. These sealing materials were evaluated as resistant to E85 up to a temperature of 70°C. Biodiesel absorbed water more quickly and aged faster than conventional diesel fuel. The weight loss of the elastomers varied between 9% (FKM) and 126% (CSM) in biodiesel. FKM was evaluated as resistant with a 16% reduction in tensile strength, a 2% reduction in breaking elongation and low weight loss. NBR, EPDM, CSM and VMQ were evaluated as not resistant. CSM even lost 84% of its original tensile strength and 78% of its breaking elongation. The highest weight gain as a result of swelling was measured for CSM with 86%, for EPDM with 84% and for VMQ with 54% in B10, while the fluorine-containing elasto-mers FKM (1%) and FVMQ (3%) absorbed much less B10 and swelled less. FKM lost 23% in tensile strength and 17% in breaking elongation; FMVQ lost 29% in ten-sile strength and 36% in breaking elongation. FMVQ was, therefore, only limited in its resistance to B10. The elastomers NBR, EPDM, CSM and VMQ were not resistant to B10 at all as the decrease in the tensile properties was significantly over 50%. NBR lost about 93% and CSM about 100% of its breaking elongation. The conclusion of the investigations at 70°C is that FKM is the most resistant sealing material in biodiesel, E85 (fuel with 85% ethanol) and B10 (heating oil with 10% biodiesel). T2 - EUROCORR 2013 - The European corrosion congress CY - Estoril, Portugal DA - 01.09.2013 KW - Compatibility KW - Sealing materials KW - Biodiesel KW - E85 KW - B10 KW - Mass loss KW - Tensile properties PY - 2013 SN - 978-989-8601-31-5 SP - 1 EP - 6 AN - OPUS4-29150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Madia, Mauro A1 - Foletti, S. A1 - Beretta, S. A1 - Cavalleri, E.A. T1 - A tool for the structural integrity assessment of turbine disks: probabilistic and numerical background N2 - Rotor disks for gas turbines are heavy components and are usually designed following a safe-life approach, where the low-cycle fatigue analysis is carried out referring to design life curves with suitable probabilistic margins. However, in the case of such a heavy component there is the possibility of rare occurrence of undetected defects or, better, the need to identify the defect acceptability for the different rotor regions (considering stress, temperature, mission profile).In order to carry out such calculations for a turbine rotor disk a software named AStrID (Assessment of the Structural Integrity of Disks) has been developed in close cooperation between Politecnico di Milano and Ansaldo Energia (AEN). This paper summarizes its background and some of the relevant features. T2 - ASME Turbo Expo 2013 - GT 2013 CY - San Antonio, TX, USA DA - 03.06.2013 PY - 2013 SP - GT2013-96029, 1-8 AN - OPUS4-29456 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sobetzki, Joana A1 - Bäßler, Ralph T1 - Corrosion behavior and limitations of duplex steel 1.4462 in artificial fluids of different geothermal wells in Germany N2 - Within the last years the use of geothermal energy as feasible energy source has risen and is going to replace fossil fuel supply more and more. Nevertheless, Service conditions in geothermal facilities are due to the Chemical composition of hydrothermal fluids and temperatures, in many cases, extreme in terms of corrosion. Since the construction of geothermal power plants shall be economical with maximum life Service, materials selection based on preliminary material qualification is essential to guarantee a secure and reliable Operation ofthose facilities. The materials selection depends on the location of a power plant respectively on the Chemical composition of the produced aquifer fluid. The duplex Steel is often used as allround solution not only for the construction of geothermal power plants, because of its combination of good mechanical and corrosion properties and its lower costs compared to other highly alloyed materials. But there are limits for the use of the duplex-steel 1.4462 regarding its corrosion behavior, with which this contribution deals. The limitations of suitability of duplex steel 1.4462 in the geothermal fluids of Molasse Basin and Upper Rhine Graben obtained by means of electrochemical measurements and exposure tests are presented below. While 1.4462 in the artificial Molasse Basin Fluid shows an excellent corrosion resistance against pitting and uniform corrosion it presents low corrosion resistance in the artificial Upper Rhine Graben Fluid due to the difference in salinity. Besides it shows a limited corrosion resistance concerning crevice corrosion. T2 - EUROCORR 2013 - The European corrosion congress CY - Estoril, Portugal DA - 01.09.2013 KW - Localized corrosion KW - Duplex steel KW - Geothermal energy PY - 2013 SN - 978-989-8601-31-5 SP - 1 (Paper 1243) AN - OPUS4-29477 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winkler, Nicolas P. A1 - Matsukura, H. A1 - Neumann, Patrick P. A1 - Schaffernicht, E. A1 - Ishida, H. A1 - Lilienthal, A. J. ED - Rudnitskaya, A. T1 - Super-Resolution for Gas Distribution Mapping: Convolutional Encoder-Decoder Network N2 - Gas distribution mapping is important to have an accurate understanding of gas concentration levels in hazardous environments. A major problem is that in-situ gas sensors are only able to measure concentrations at their specific location. The gas distribution in-between the sampling locations must therefore be modeled. In this research, we interpret the task of spatial interpolation between sparsely distributed sensors as a task of enhancing an image's resolution, namely super-resolution. Because autoencoders are proven to perform well for this super-resolution task, we trained a convolutional encoder-decoder neural network to map the gas distribution over a spatially sparse sensor network. Due to the difficulty to collect real-world gas distribution data and missing ground truth, we used synthetic data generated with a gas distribution simulator for training and evaluation of the model. Our results show that the neural network was able to learn the behavior of gas plumes and outperforms simpler interpolation techniques. T2 - 19th International Symposium on Olfaction and Electronic Nose CY - Aveiro, Portugal DA - 29.05.2022 KW - Gas Distribution Mapping KW - Spatial Interpolation KW - Deep Learning KW - Super-Resolution KW - Sensor Network PY - 2022 SN - 978-1-6654-5860-3 DO - https://doi.org/10.1109/isoen54820.2022.9789555 SP - 1 EP - 3 PB - IEEE CY - USA AN - OPUS4-54955 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Nehrig, Marko A1 - Scheidemann, Robert A1 - Wille, Frank A1 - Ballheimer, Viktor T1 - Investigation of the internal impact during a 9 m drop test of an accident-safe waste package N2 - The safety assessment of packages for the transport of radioactive material follows the IAEA regulations and guidance. The specified regulatory tests cover severe accidents and demonstrate the package containment system integrity. Special attention must be drawn to the behaviour of the content which could move inside the package due to unpreventable gaps caused by the loading procedure and the structure of the content. A possible internal impact of the content which occurs during the drop tests onto the lid system is investigated. The IAEA regulations SSR-6 and the Guidance SSG-26, revised recently, consider input from Germany and France related to the significance of internal gaps. In the context of a waste package design assessment, a model was equipped with a representative content to conduct a drop test with an internal impact. The weight and kinetic impact of this content covered all possible real contents. The objective of the test was to maximize the load onto the lid system and to prove the mechanical integrity by complying with the required leak tightness. The test was conducted conservatively at a package temperature lower than -40 °C at the BAM Test Site Technical Safety. This paper gives an overview of efforts to address internal gaps and their consequences, and the BAM efforts with the implementation of this topic into IAEA regulations and guidance material. The paper then focuses on the conduction of a drop test and investigation of internal component impact. T2 - ASME 2021 Pressure Vessels & Piping Conference (PVP2021) CY - Online meeting DA - 13.07.2021 KW - Internal gaps KW - Drop test KW - IAEA PY - 2021 SN - 978-0-7918-8535-2 DO - https://doi.org/10.1115/PVP2021-60996 SP - 1 EP - 6 PB - American Society of Mechanical Engineers (ASME) CY - New York, NY, USA AN - OPUS4-54742 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Beckmann, Jörg A1 - Puskar, L. A1 - Ritter, E. A1 - Schade, U. T1 - Novel Technique for On-Line Monitoring of the Curing Process of Fiber Reinforced Polymer Composites N2 - A specially developed experimental set up has been integrated into a commercially available FT IR Spectrometer to study the curing of Epoxy Systems. MIR and FIR spectra measured during the curing process at different temperatures of an epoxy system will be presented in dependency of the curing time. The experiments and the selected set up are discussed to demonstrate its potential for future monitoring and ageing control applications during a manufacturing process of polymer composites. T2 - 45. International conference on infrared, millimeter, and terahertz waves CY - Online meeting DA - 08.11.2020 KW - Far-infrared spectroscopy KW - Online Curing Monitoring PY - 2021 SN - 978-1-7281-6620-9 DO - https://doi.org/10.1109/irmmw-thz46771.2020.9370646 SP - 1 PB - IEEE AN - OPUS4-53059 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Baeßler, Matthias A1 - Herten, M. A1 - Rumpf, M. A1 - Tronicke, J. ED - Coutinho, R.Q. ED - Mayne, P.W. T1 - Geotechnical and geophysical characterization of a pile test site in post-glacial soil N2 - Two research institutes are currently evaluating dynamic pile load testing methods on bored piles in a sandy environment. A test site has been prepared, which ensures comparable conditions at all pile locations and provides detailed knowledge on soil and other boundary conditions. A detailed site investigation program was performed at a dedicated area on the BAM test site south of Berlin, Germany. Undisturbed soil samples have been collected from boreholes. In addition several CPTs and geophysical surveys have been performed. The site consists mainly of well graded, partly well compacted medium sands. But at depth an inhomogeneous gravel layer was detected in some parts of the site. This has led to a redesign of the test piles. They are now shorter than originally intended to avoid gravel layers at depth and to ensure that the drop weight available for dynamic test is capable to mobilize the required load. T2 - ISC-4 - 4th International conference on site characterization - Geotechnical and geophysical site characterization 4 CY - Pernambuco, Brazil DA - 17.09.2012 KW - Dynamic pile testing KW - Test site KW - CPT KW - Seismic tomography KW - Seismic crosshole PY - 2013 SN - 978-0-415-62136-6 VL - I SP - 459 EP - 464 PB - CRC Press AN - OPUS4-27492 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Galindo Guerreros, Julio Cesar A1 - Mackens, S. A1 - Niederleithinger, Ernst A1 - Fechner, T. ED - Manzanal, D. ED - Sfriso, A. O. T1 - Numerical simulations of crosshole and downhole seismic measurements as quality control tool for jet grout columns N2 - Sealing and strengthening of the subsoil by injection is a major issue in the field of geotechnical engineering. This involves also jet grouting, which allows creating columns of grouted soil by eroding and mixing the in-situ soil with a thin cement suspension. A general difficulty of this method is to predict the column diameter and its material strength. Here, we present two-dimensional finite-difference numerical simulation results of a promising non-destructive quality assurance testing tool to evaluate the diameter of jet grout columns. This approach incorporates crosshole and downhole seismic measurements. Preliminary tests showed that this tool is applicable under real site conditions. T2 - 15th Pan-American Conference on Soil Mechanics and Geotechnical Engineering CY - Buenos Aires, Argentina DA - 15.11.2015 KW - Jet grout KW - Diameter KW - Seismic KW - Crosshole KW - Downhole KW - FD KW - Quality control tool PY - 2015 SN - 978-1-61499-603-3 SN - 978-1-61499-602-6 DO - https://doi.org/10.3233/978-1-61499-603-3-985 SP - Part 1, 985 EP - 992 PB - IOS Press AN - OPUS4-37706 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Sens-Schönfelder, C. A1 - Grothe, Sven A1 - Wiggenhauser, Herbert T1 - Coda wave interferometry used to localize compressional load effects on a concrete specimen N2 - Coda Wave Interferometry (CWI), a method to evaluate subtle changes of elastic wave velocity in a medium, has been proven to be effective to detect small changes or ultrasonic velocity in concrete caused by load, temperature, moisture, damage or other means. While classical CWI is just able to determine velocity changes globally in relatively large areas between and around pairs of transmitters and receivers, several approaches have been proposed to identify the area affected by the changes more precisely. Most of them are based on the calculation of sensitivity kernels for de-correlation of signals measured at a specific state against a reference. Others follow simplified approaches. In a laboratory setup a concrete specimen of 1:5 x 1:5 x 0:5 m3 was compressed at a certain point. Maximum loads of 20 to 100 kN have been applied in 5 to 10 kN steps in various cycles. The specimen is equipped with 18 embedded ultrasonic broadband piezo transceivers (60 kHz central frequency). Ten of these receivers have been connected to a multiplexer and ultrasonic transmitting and receiving equipment in a way that allowed almost continuous two way measurements between all sensor pairs. Even simple ways to evaluate the data (e.g. crosscorrelation between signals at different load states) allowed pinpointing the load center at least approximately. A more detailed data evaluation either using CWI or even more one of the more sophisticated localization algorithms gave “sharper” results in terms of localization and a better correlation between load and velocity change/de-correlation. The results are used in upcoming monitoring systems for concrete structures. T2 - 7th European workshop on structural health monitoring CY - Nantes, France DA - 08.07.2014 KW - Concrete KW - Ultrasound KW - Coda wave inteferometry KW - Tomography KW - Correlation KW - Stress KW - Monitoring PY - 2014 SP - Paper WeBT6.3, 1427 EP - 1433 AN - OPUS4-31204 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst A1 - Wunderlich, Carolin T1 - Influence of small temperature variations on the ultrasonic velocity in concrete N2 - Ultrasonic methods are valuable tools for quality assessment and structural imaging of concrete. In such applications, accurate and reliable determination of ultrasonic wave velocities is essential, as they are affected by various experimental and environmental factors. In this research coda wave interferometry (CWI) was used to determine the influence of temperature (0 to 50 °C) on ultrasonic wave velocity in concrete samples. A resolution of better than 10-4 was achieved in the measurement of relative velocity changes. Reversibility and repeatability as well as the influence of moisture were taken into account. In addition the influence of sensor (transmitter and receiver) positioning errors on the results of the interferometric algorithm was evaluated as well as the benefit of newly developed, permanently embedded sensors. The presented results can be used to evaluate and refine data from ultrasonic monitoring systems. T2 - 39th Annual review of progress in quantitative nondestructive evaluation CY - Denver, Colorado, USA DA - 15.07.2012 KW - Ultrasonic KW - Concrete KW - Scattering KW - Coda wave interferometry KW - Temperature PY - 2013 SN - 978-0-7354-1129-6 DO - https://doi.org/10.1063/1.4789074 SN - 0094-243X SN - 1551-7616 N1 - Serientitel: AIP conference proceedings – Series title: AIP conference proceedings VL - 1511 SP - 390 EP - 397 AN - OPUS4-29052 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Niederleithinger, Ernst ED - Coutinho, R.Q. ED - Mayne, P.W. T1 - Two in one: parallel seismic for foundation length determination and downhole seismic for soil properties using a single borehole N2 - Parallel Seismic was introduced about four decades ago for foundation length estimation. As the borehole required by this test is in most cases more expensive than the test itself, the usage is limited so far. In addition the graphical Interpretation technique which is still state of the art tends to overestimate the length and neglects several geometrical Parameters. New Interpretation algorithms have been recently introduced rely on model based travel time curve Utting. They improve the accuracy and extend the maximum ränge (distance pile to borehole) of the method. Borehole or pile inclination as well as soil layering can be considered. If the location is properly chosen, several piles can be tested using a single borehole. The capabilities and limitations of the methods have been tested using simulations and measurements at the BAM-TTS test site in Horstwalde south of Berlin and several commercial projects involving piles, pile secant walls and sheet piles. To improve the accuracy of the method as well as to provide additional Parameters to the geotechnical engineer it is recommended to use the borehole for Downhole Seismic measurements. Determination of compressional and shear wave velocities can be used to determine the dynamic elastic properties of the subsoil. The approach is evaluated again on the BAM-TTS test site. The affectivity of this kind of combiuation can be further enhanced by using a seismic cone. T2 - ISC-4 - 4th International conference on site characterization - Geotechnical and geophysical site characterization 4 CY - Pernambuco, Brazil DA - 17.09.2012 KW - Parallel seismic KW - Downhole seismic KW - Foundation piles KW - Length KW - Shear wave velocity PY - 2013 SN - 978-0-415-62136-6 VL - I SP - 453 EP - 458 PB - CRC Press AN - OPUS4-27491 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg A1 - Becker, Ben A1 - Scholz, Irene T1 - Assessment of the type of statistical distribution concerning strength properties of composite cylinders N2 - Composite materials show a degradation of properties depending on service life. This creates the necessity to find tailored methods to determine strength and residual strength of composite cylinders. The determination can be done e.g. by load cycles tests. The result needs a statistical assessment for the precise description of strength. Especially the statistical assessment of load cycle strength properties has a high uncertainty. It is unclear if a Log-Normal distribution, a WEIBULL distribution or others, describe the scatter behaviour of residual strength properties correctly. Distribution functions aim at approximating the frequency of occurrence of residual load cycle strength for high survival rates. An assumption has to be found and confirmed to prevent over-estimation of reliability. T2 - ICCM20 - 20th International conference on composite materials CY - Copenhagen, Denmark DA - 19.07.2015 KW - Composite cylinder KW - Load cycle test KW - Statistical assessment KW - Distribution function PY - 2015 SN - 978-1629931999 SP - P-ID 2217-2/Track 4-04, 1-11 AN - OPUS4-33792 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheidemann, Robert A1 - Weber, Mike A1 - Völzke, Holger A1 - Kasparek, Eva Maria ED - Gomes, J.F.Silva ED - Meguid, S.A. T1 - Temperature dependendency of dynamically loaded polyurethane foam N2 - Polyurethane foam used as impact limiter material undergoes high plastic deformations, whereat the resulting stress-strain relations strongly depend on loading speed and temperature. This paper discusses the efforts necessary to develop a reliable numerical foam simulation model focussing on generation and implementation of temperature- dependent yield curves T2 - 6th International Conference on Mechanics and Materials in Design CY - Ponta Delgada, Azores, Portugal DA - 26.07.2015 KW - Impact limiter KW - Polyurethane foam KW - Finite element model KW - Strain rate KW - Temperature dependency PY - 2015 SN - 978-989-98832-3-9 SP - 1043 EP - 1046 PB - INEGI-FEUP AN - OPUS4-38889 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - de Miguel, N. A1 - Mair, Georg A1 - Acosta, B. A1 - Szczepaniak, Mariusz A1 - Moretto, P. T1 - Hydraulic and pneumatic pressure cycle life test results on composite reinforced tanks for hydrogen storage N2 - Current standards governing the design, qualification and in-service inspection of carbon fibre composite cylinders do not facilitate to optimise cylinder design. The requirements have been adapted from standards for metallic cylinders and cannot easily quantify the degradation processes in composite materials. In this article, the results of hydraulic and hydrogen pressure cycle life tests performed on composite reinforced tanks with a metal liner (type 3) and with a high density polymer liner (type 4) are shown. Moreover, the degradation measured by means of residual strength of the tanks after the cycling tests have been compared. It has been found that the most critical aging for metal based composite cylinder is the gaseous cycling while type 4 designs seem to be more sensitive to hydraulic cycling at high temperature. T2 - ASME 2016 Pressure Vessels and Piping Conference CY - Vancouver, British Columbia, Canada DA - 17.07.2016 KW - Composite reinforced tanks KW - Compressed hydrogen storage KW - Design and qualification standards KW - Pressure cycle life tests KW - Safety factors PY - 2016 SN - 978-0-7918-5035-0 VL - 1A SP - 63568-1 EP - 63568-10 PB - ASME CY - Vancouver, British Columbia, Canada AN - OPUS4-36275 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Unger, Jörg F. ED - Idelsohn, S. ED - Sonzogni, V. ED - Coutinho, A. ED - Cruchaga, M. ED - Lew, A. ED - Cerrolaza, M. T1 - Numerical simulation of ultrasonic wave propagation using higher order methods in space and time N2 - The paper discusses the efficient simulation of ultrasonic wave propagation. It is demonstrated that a combination of higher methods in space and time leads to a significant performance boost. Higher order spectral elements are used for the spatial discretization. A comparison with standard finite elements shows the advantages when using explicit time integration schemes. For the temporal discretization, an efficient explicit fourth order Nyström method is presented. Its computational efficiency for wave propagation problems is compared to a second order Velocity Verlet integration. T2 - 1st Pan-American Congress on Computational Mechanics - PANACM 2015 CY - Buenos Aires, Argentina DA - 27.04.2015 KW - Elastic wave propagation KW - Spectral element method KW - Nyström methods PY - 2015 SN - 978-84-943928-2-5 SP - 1041 EP - 1052 PB - International Center for Numerical Methods in Engineering (CIMNE) CY - Barcelona, Spain AN - OPUS4-38645 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weber, Mike A1 - Kömmling, Anja A1 - Jaunich, Matthias A1 - Wolff, Dietmar A1 - Zencker, Uwe A1 - Völzke, Holger A1 - Schulze, Dietmar A1 - Probst, Ulrich T1 - Testing and Numerical Simulation of Elastomers - From Specimen Tests to Simulation of Seal Behavior under Assembly Conditions N2 - Due to delays in the siting procedure to establish a deep geological repository for spent nuclear fuel and high level radioactive waste as well as in construction of the already licensed Konrad repository for low and intermediate level radioactive waste, extended periods of interim storage become more relevant in Germany. BAM is involved in most of the cask licensing procedures and especially responsible for the evaluation of cask-related long-term safety issues. The long-term performance of elastomer seals for lid systems of transport and storage casks, whether used as auxiliary seals in spent fuel casks or as primary seals for low and intermediate level waste packages, is an important issue in this context. The polymeric structure of these seals causes a complex mechanical behavior with time-dependent sealing force reduction. The results of a comprehensive purpose-designed test program consisting of basic compression and tension tests as well as relaxation tests on unaged specimens of representative types of elastomers (fluorocarbon rubber (FKM) and ethylene propylene diene rubber (EPDM)) at different temperatures and strain rates are presented. They were used to identify the constitutive behavior and to obtain parameters for finite element material models provided by the computer code ABAQUS®. After estimating the influence of uncertainties such as Poisson’s ratio and friction coefficient by sensitivity analyses, the chosen parameters had to prove their suitability for the finite element simulation of the specimen tests themselves. Based on this preliminary work the simulation of a specific laboratory test configuration containing a typical elastomer seal with circular cross section is presented. The chosen finite element material model and the implemented parameters had to show that they are able to represent not only the specimen behavior under predominantly uniaxial load but also the more complex stress states in real components. Deviations between the measured and calculated results are pointed out and discussed. For the consideration of long-term effects in the simulation of elastomer behavior, test results of aged specimens are needed. First information about a new test program, started recently and planned to provide these data, are given. T2 - ASME 2017 Pressure Vessels & Piping Conference (PVP2017) CY - Waikoloa, Hawaii, USA DA - 16.07.2017 KW - Time dependent effects KW - Low temperature behavior KW - Elastomeric seals KW - Aging KW - Simulation KW - Testing PY - 2017 SN - 978-0-7918-5802-8 VL - 7 SP - Article UNSP V007T07A035, 1 EP - 8 AN - OPUS4-41841 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weber, Mike A1 - Kömmling, Anja A1 - Jaunich, Matthias A1 - Wolff, Dietmar A1 - Zencker, Uwe A1 - Völzke, Holger A1 - Schulze, Dietmar T1 - Testing and numerical simulation of elastomeric seals under consideration of time dependent effects N2 - Due to delays in the siting procedure to establish a deep geological repository for spent nuclear fuel and high level waste and in construction of the already licensed Konrad repository for low and intermediate level waste, extended periods of interim storage will become more relevant in Germany. BAM is involved in most of the cask licensing procedures and is responsible for the evaluation of cask-related long-term safety issues. Elastomeric seals are widely used as barrier seals for containers for low and intermediate level radioactive waste. In addition they are also used as auxiliary seals in spent fuel storage and transportation casks (dual purpose casks (DPC)). To address the complex requirements resulting from the described applications, BAM has initiated several test programs for investigating the behavior of elastomeric seals. These include experiments concerning the hyperelastic and viscoelastic behavior at different temperatures and strain rates, the low temperature performance down to -40°C, the influence of gamma irradiation and the aging behavior. The first part of the paper gives an overview of these tests, their relevant results and their possible impact on BAM’s work as a consultant in the framework of approval and licensing procedures. The second part presents an approach of the development of a finite element model using the finite element code ABAQUS®. The long-term goal is to simulate the complex elastomeric behavior in a complete lid closure system under specific operation and accident conditions. T2 - ASME 2016 Pressure Vessels & Piping Conference (PVP2016) CY - Vancouver, BC, Canada DA - 17.07.2016 KW - Elastomeric seals KW - Testing KW - Low temperature behavior KW - Aging KW - Simulation KW - Time dependent effects PY - 2016 SN - 978-0-7918-5045-9 VL - 7 SP - Paper 63192, 1 EP - 10 AN - OPUS4-37046 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg A1 - Hoffmann, Martin A1 - Schönfelder, Thorsten ED - Carcassi, M.N. T1 - The slow burst testing of composite cylinders - Part I: Slow burst testing of samples as a method for quantification of cylinder degradation N2 - The current practise of focusing the periodic retesting of composite cylinders primarily on the hydraulic pressure test has to be evaluated as critical - with regard to the damage of the specimen as well as in Terms of their significance. This is justified by micro damages caused to the specimen by the test itself and by a lack of informative values. Thus BAM Federal Institute of Materials Research and Testing (Germany) uses a new approach of validation of composite for the determination of re-test periods. It enables the description of the state of a population of composite cylinders based on destructive tests parallel to operation. An essential aspect of this approach is the prediction of residual safe service life. In cases where it cannot be estimated by means of hydraulic load cycle tests, as a replacement the creep or burst test remains. As a combination of these two test procedures BAM suggests the 'slow burst test SBT'. On this a variety of about 150 burst test results on three design types of cylinders with plastic liners are presented. For this purpose both, the parameters of the test protocol as well as the nature and intensity of the pre-damage artificially aged test samples are analysed statistically. This leads first to an evaluation of the different types of artificial ageing but also to the clear recommendation that conventional burst tests be substituted totally if indented for assessment of composite pressure receptacles. T2 - ICHS2013 - 5th International conference on hydrogen safety CY - Brussels, Belgium DA - 09.09.2013 KW - Residual strength KW - CFRP KW - Gas storage KW - Reliability KW - Sample testing PY - 2013 SN - 978-2-9601366-0-9 SP - 1 EP - 12 AN - OPUS4-29260 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völzke, Holger A1 - Wolff, Dietmar T1 - Safety aspects of long dry interim cask storage of spent fuel in Germany N2 - Dry cask storage of spent fuel and high active waste front reprocessing is licensed and established in Germany for up to 40years so far. About 10years ago, the strategy has been shifted from centralized storage using facilities in Ahaus and Gorleben to cit-site storage facilities in Order to avoid immediate cask shipping from nuclear power plants. At present, several hundred casks are stored safeiy and without any major problem. BAM is highly involved in cask specific safety evaluations within the scope of licensing procedures as well as of quality assurance procedures during cask fabrication, loading and storage. A major prerequisite for any cask storage license is a valid transport Type B license. Subsequently, cask transportability has to be ensured at any point during the entire storage period. So far, this requirement is met by continuous maintenance of the Type B license. Anyhow, IAEA Type B regulations do not consider permanently loaded storage casks that have the sole purpose of being finally shipped öfter decades of storage inducing ageing effects. No transport safety demonstration has to be performed on aged cask components. T2 - International high-level radioactive waste management conference (IHLRWMC 2011) CY - Albuquerque, NM, USA DA - 10.04.2011 KW - Safety KW - Cask KW - Interim storage KW - Spent fuel PY - 2011 SP - 712 EP - 719 AN - OPUS4-23651 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ellouz, Manel A1 - Völzke, Holger A1 - Kasparek, Eva Maria T1 - BAM challenges for design testing of waste containers for the final repository Konrad N2 - Up to the end of this decade, corresponding to the planned date of starting operation in the final disposal KONRAD for non-heat generating waste in Germany, a lot of efforts are needed to condition and package the radioactive waste in containers certified by BfS (Federal Institute for Radiation Protection). This waste is produced by public sector and industry as well as nuclear energy facilities, which result in more than a half of the actually declared quantity growing especially after the phase out decision of nuclear power production in Germany and the subsequent decommissioning of nuclear power plants. BAM (Federal Institute for Materials Research and Testing) acts as responsible authority on behalf of BfS for design testing under consideration of the KONRAD requirements. Within the assessment procedure of containers, BAM has to verify the application documents, including material qualification, container geometry, corrosion protection, leakage rate and operational and accidental loading, and to evaluate quality assurance measures. Besides the previous completed approvals for various containers such as steel sheet and cast iron box-shaped containers and concrete cylindrical ones, BAM is actually carrying assessments for other types such as cast iron cylindrical containers and “old” steel sheet box shaped ones. The so called “old” containers present already loaded containers without any KONRAD certification, currently stored at licensed interim storages. In the benefit of the container assessment, BAM operates design testing facilities for drop and fire tests which are also used for research objectives to improve and expand the evaluation methods such as research project ConDrop. The latter deals with numerical simulations and analyses tools for further precise predictions about unfavorable drop test scenarios, safety margins, and design sensitivities for steel sheet containers. Furthermore, during the assessment procedure, several specifications about the containers, the inventory to be disposed and the required safety level have been intensely debated by authorities and applicants. Based on its experience in qualifying containers, BAM has been commissioned to identify insufficiently specified aspects in the waste acceptance criteria and to propose clearer definitions with regard to the secondary regulations in the planning approval notice. This paper focuses on aspects of the contribution of BAM in certifying KONRAD waste containers. This will include the current state of design testing procedures, evaluation methods that are available or are being developed and the main topics within the KONRAD requirements being actually specified by BAM. T2 - ICEM 2013 - 15th International Conference on environmental remediation and radioactive waste management CY - Brussels, Belgium DA - 08.09.2013 PY - 2013 IS - ICEM2013-96258 SP - 1 EP - 9 AN - OPUS4-29468 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völzke, Holger T1 - The German aging management approach for dry spent fuel storage in dual purpose casks N2 - Since the decision by the German government to face out nuclear electricity generation the total amount of spent nuclear fuel and high level wastes from reprocessing is limited and well determined. In addition the siting and licensing procedure to establish a final repository has been ruled by a new law in the mid of 2013 and further delays are very likely until a deep geological repository may start its operation. In the meantime dry interim storage in dual purpose casks being permanently certified for interim storage as well as transportation is the established technical solution. Several on-site as well former centralized facilities are operated successfully for many years but storage licenses are generally limited to 40 years and future lifetime extensions are predictable. Permanent aging management for storage facilities and casks is necessary to demonstrate compliance with safety requirements and furthermore to gain relevant data and information about the technical conditions of the facilities and their components for future lifetime extensions. For that reason procedures and measures are currently improved and the approach is explained in this paper. In addition, the current status and latest experiences concerning periodic safety inspections and aging management measures are discussed. T2 - PSAM 12 - Probabilistic safety assessment and management CY - Honolulu, Hawaii, USA DA - 22.06.2014 KW - Interim storage KW - Dual purpose casks KW - Spent nuclear fuel KW - Aging management PY - 2014 SP - T06 - Doc.183, 1-7 AN - OPUS4-32250 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Grützner, Stefan A1 - Rehmer, Birgit A1 - Fedelich, Bernard A1 - Mosquera Feijoo, Maria T1 - Deformation modeling and lifetime prediction of Ni-base gas turbine blade alloys under TMF-conditions N2 - Under cyclic thermomechanical loading conditions, various effects such as strain accumulation, creep damage, ageing, fatigue etc. may occur in the material of a gas turbine blade. Depending on the loading conditions, all these effects contribute to reduce the lifetime of the component. Subject of the present work is the development of a lifetime model able to discriminate between the different damage mechanisms, as well as the development of a material model to describe the mentioned effects and thus providing the input data for lifetime prediction. T2 - ASME Turbo Expo 2014 - GT2014 CY - Düsseldorf, Germany DA - 16.06.2014 KW - Ni-base super alloy KW - Viscoplastic KW - Ratcheting KW - Creep KW - Strain induced ageing KW - Fatigue KW - Oxidation damage PY - 2014 SN - 978-0-7918-4576-9 SP - GT2014-26332, 1-7 AN - OPUS4-30962 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Qiao, Linan A1 - Zencker, Uwe A1 - Völzke, Holger ED - Brandt, A. M. ED - Olek, J. ED - Glinicki, M. A. ED - Leung, C.K.Y. ED - Lis, J. T1 - Crushable foam model with pressure and stress-triaxiality dependent damage mechanisms for damping concrete N2 - Damping concrete with high energy absorption capability consists of a cement matrix with embedded small polystyrene balls and is investigated experimentally and numerically under high static compression with and without clamping. A material model is derived which describes the fundamental effects of damping concrete like non-linear elastic-plastic behaviour, volume change, volume strain dependent hardening as well as shear failure with an adequate description of damage initiation and evolution. The suggested material model is validated by simulation of penetration tests. T2 - BMC-11, International Symposium on Brittle Matrix Composites CY - Warsaw, Poland DA - 28.09.2015 KW - Damping concrete KW - Impact load KW - Crushable foam material model KW - Damage PY - 2015 SN - 978-83-89687-96-8 SP - 269 EP - 277 PB - Inst Fundamental Technological Research, Polish Acad Sciences CY - Warschau AN - OPUS4-34613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zencker, Uwe A1 - Qiao, Linan A1 - Völzke, Holger T1 - Dynamic finite element analysis of cask handling accidents at storage sites N2 - The safety assessment of casks for radioactive material at interim storage facilities or in final repositories includes the investigation of possible handling accidents if clearly defined test conditions are not available from the regulations. Specific handling accidents usually are the drop of a cask onto the transport vehicle or the floor as well as the collision with the wall of the storage building or another cask. For such load cases an experimental demonstration of cask safety would be difficult. Therefore, numerical analyses of the entire load scenario are preferred. The lessons learnt from dynamic finite element analyses of accident scenarios with thick-walled cubical containers or cylindrical casks are presented. The dependency of calculation results on initial and boundary conditions, material models, and contact conditions is discussed. Parameter sets used should be verified by numerical simulation of experimentally investigated similar test scenarios. On the other hand, decisions have to be made whether a parameter or property is modeled in a realistic or conservative manner. For example, a very small variation of the initial impact angle of a container can cause significantly different stresses and strains. In sophisticated cases an investigation of simpler limit load scenarios could be advantageous instead of analyzing a very complicated load scenario. T2 - ASME 2015 Pressure vessels & piping conference - PVP2015 CY - Boston, Massachusetts, USA DA - 19.07.2015 KW - Finite element method KW - Simulation KW - Cask handling accident KW - Interim storage PY - 2015 SN - 978-0-7918-5702-1 SP - Paper 45606, 1 EP - 10 AN - OPUS4-34937 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Zencker, Uwe A1 - Qiao, Linan A1 - Völzke, Holger T1 - Influence of impact angle and real target properties on drop test results of cubic containers N2 - Drop test scenarios with cubic containers without impact limiters at interim storage sites or in a final repository have been investigated by numerical simulations. An ideally flat drop is impossible to conduct as a free fall of a container even under laboratory conditions. Dynamic stresses and strains inside the container structure are sensitive to the impact angle. Even very small impact angles cause remarkable changes in the experimental or numerical results when a flat bottom or wall of a container hits a flat target. For drop tests with transport packages the International Atomic Energy Agency (IAEA) regulations define an essentially unyielding target. In contrast, potential accident scenarios for storage containers are derived from site-specific safety analyses or acceptance criteria in Germany. Each interim storage site or repository has a yielding or so-called real target with individual structural and material properties. The real target acts as a kind of impact limiter. A more conservative container design is required if the impact limiting effect of the target is not considered. T2 - ASME 2017 Pressure Vessels and Piping Conference CY - Waikoloa, Hawaii, USA DA - 16.07.2017 KW - Finite element method KW - Simulation KW - Drop test KW - Impact angle KW - Real target KW - Yielding target PY - 2017 SN - 978-0-7918-5802-8 DO - https://doi.org/10.1115/PVP2017-65731 VL - 7 SP - Article UNSP V007T07A039, 1 EP - 9 AN - OPUS4-43631 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Casperson, Ralf A1 - Pohl, Rainer A1 - Munzke, Dorit A1 - Becker, Ben A1 - Pelkner, Matthias T1 - Eddy current testing of composite pressure vessels N2 - The use of composite pressure vessels instead of conventional vessels made of steel or aluminum grew strongly over the last decade. The reason for this trend is the tremendous weight saving in case of composite vessels. However, the long-time behavior is not fully understood for filling and discharging cycles and creep strength and their influence on the CFRP coating (carbon fiber reinforced plastics) and the internal liner (steel, aluminum, or plastics). The CFRP ensures the pressure resistance while the inner liner is used as container for liquid or gas. To overcome the missing knowledge of ageing BAM started an internal project to investigate degradation of these material systems. Therefore, applicable testing methods like eddy current testing are needed. Normally, high-frequency eddy current testing (HF-ET, f > 10 MHz) is deployed for CFRP due to its low conductivity of the fiber, which is in the order of 0.01 MS/s, and the capacitive coupling between the fibers. Nevertheless, in some cases conventional ET can be applied. We show a concise summary of studies on the application of conventional ET of composite pressure vessels. T2 - QNDE 2017 CY - Provo, Utah, USA DA - 16.07.2017 KW - Eddy current KW - Composite KW - Pressure vessel PY - 2018 SN - 978-0-7354-1644-4 DO - https://doi.org/10.1063/1.5031622 SN - 0094-243X VL - 1949 SP - UNSP 160004, 1 EP - 8 AN - OPUS4-45051 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sieg, H. A1 - Lehmann, C. A1 - Kästner, Claudia A1 - Krause, B. A1 - Burel, A. A1 - Chevance, S. A1 - Böhmert, L. A1 - Lichtenstein, D. A1 - Tentschert, J. A1 - Bräuning, A. A1 - Laux, A. A1 - Thünemann, Andreas A1 - Loipis, I. E. A1 - Fessard, V. A1 - Luch, A. A1 - Lampen, A. T1 - Effects of Al-, Ti- and Zn-containing nanomaterials on cell lines in vitro N2 - Among the different tested endpoints, Al- and Ticontaining nanomaterials did notshowany toxicity in intestinal cell lines in vitro. Nevertheless, this absence of effect was not due to an absence of exposure, since particle-specific uptake was reported. Metal particle uptake over a long time period might therefore be relevant for risk assessment of aluminum- and titanium-containing food products. T2 - 52nd Congress of the European-Societies-of-Toxicology (EUROTOX) CY - Seville, Spain DA - 04.09.2017 KW - Nanoparticles PY - 2017 DO - https://doi.org/10.1016/j.toxlet.2016.06.1954 SN - 0378-4274 VL - 258 SP - S272 PB - Elsevier Ltd. AN - OPUS4-40939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Heinke, D. A1 - Gehrke, N. A1 - Ludwig, F. A1 - Steinhoff, U. A1 - Pankhurst, Q. A. A1 - Lüdtke-Buzug, K. A1 - Thünemann, Andreas A1 - Johansson, Ch. T1 - NanoMag - Standardization of Analysis Methods for Magnetic Nanoparticles N2 - The NanoMag project brings together various leading experts in magnetic nanoparticle synthesis as well as nanoparticle analysis and characterization from research institutes, companies, universities and metrology institutes that will perform cutting-edge research and develop applications in the field of magnetic particles. This work is supported by the European Commission Framework Programme7 under the NanoMag project [grant agreement no 604448]. T2 - 2015 5th International Workshop on Magnetic Particle Imaging (IWMPI) CY - Istanbul, Turkey DA - 26.03.2015 KW - nanoparticles PY - 2015 UR - http://www.nanomag-project.eu/ SN - 978-1-4799-7269-2 SN - 978-1-4799-7271-5 DO - https://doi.org/10.1109/IWMPI.2015.7107065 VL - 2015 SP - P39 PB - IEEE AN - OPUS4-37324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lichtenstein, D. A1 - Meyer, Th. A1 - Böhmert, L. A1 - Sieg, H. A1 - Juling, S. A1 - Thünemann, Andreas A1 - Lopies, I. E. A1 - Bräuning, A. A1 - Lampen, A. T1 - Evidence for particle-specific and coating-related uptake of silver nanoparticles N2 - Present data indicate that the quantification of silver nanoparticle internalization revealed a clear particle-specific and coatingrelated uptake. Furthermore, a high amount of silver nanoparticles is taken up in cell models of higher complexity. Thus, an underestimation of particle effects in vitro might be prevented by considering cell models with greater proximity to the in vivo situation. T2 - 52nd Congress of the European-Societies-of-Toxicology (EUROTOX) CY - Seville, Spain DA - 04.09.2016 KW - Small-angle X-ray scattering KW - SAXS KW - Nanoparticle KW - Silver PY - 2017 DO - https://doi.org/10.1016/j.toxlet.2016.06.1938 SN - 0378-4274 VL - 258 SP - S267 EP - S267 PB - Elsevier Ltd. AN - OPUS4-40936 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lichtenstein, D. A1 - Böhmert, L. A1 - Meyer, Th. A1 - Sieg, H. A1 - Thünemann, Andreas A1 - Loipis, I. E. A1 - Bäuning, A. A1 - Lampen, A. T1 - Core or coating material? What dictates the uptake and translocation of nanoparticles in vitro? N2 - A core-dependent effect on nanoparticle translocation was revealed. Both the uptake and transport of nanoparticles in and through cells should be considered when discussing nanoparticle fate and safety. T2 - 52nd Congress of the European-Societies-of-Toxicology (EUROTOX) CY - Seville, Spain DA - 04.09.2016 KW - Small-angle X-ray scattering KW - SAXS KW - Silver KW - Nanoparticle PY - 2017 DO - https://doi.org/10.1016/j.toxlet.2016.06.1940 SN - 0378-4274 SN - 1879-3169 VL - 258 SP - S267 EP - S268 PB - Elsevier Ltd. AN - OPUS4-40935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheid, Marc A1 - Klippel, Alexander A1 - Tschirschwitz, Rico A1 - Schröder, Volkmar A1 - Zirker, Stefan A1 - Kusche, Christian T1 - New ignition source 'exploding wire' for the determination of explosion characteristics of combustible dusts in the 20-L-sphere N2 - According to international Standards several safety characteristics of dusts are determined in the 20-L-sphere (also known as SIWEK-Chamber). Dust cloud ignition is carried out using pyrotechnical igniters. Due to various disadvantages of pyrotechnical igniters the need for alternative ignition sources arises again and again. An alternative ignition source could be the socalled “exploding wire” or “fuse wire". The paper presents test results of a comparative study between both ignition sources for the determination of the safety characteristics Maximum Explosion Pressure and Maximum Rate of Explosion Pressure Rise of selected dusts in the 20-Lsphere. In addition to that the flame/arc propagation of both ignition sources was analysed by high speed and IR camera recordings. Tests in a windowed autoclave were performed to get information on the influence of turbulence generated due to dispersion of the dust on the shape of the generated flame and its propagation. Turbulence measurements in the windowed autoclave as well as in the 20-L-sphere with a LDA System allowed investigation if the igniter led to turbulence increase at the moment of ignition in comparison to tests without ignition. T2 - GCPS 2013 - 9th Global congress on process safety CY - San Antonio, TX, USA DA - 28.04.2013 KW - Sicherheitstechnische Kenngrößen Staub KW - Staubexplosionsschutz KW - Explodierender Draht KW - Alternative Zündquelle PY - 2013 SN - 978-0-8169-1075-5 SP - 1 EP - 10 AN - OPUS4-28552 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schade, U. A1 - Puskar, L. A1 - Ritter, E. A1 - Beckmann, Jörg T1 - Etalon effects in THz film measurements N2 - Etalon effects in THz transmittance spectra, either taken in time- domain or frequency-domain, often hamper or even hinder the interpretation of film properties. In this paper we discuss the transferability and applicability of spectroscopic methods typically employed in the near and mid infrared spectral range to eliminate the fringes in the transmittance spectra in the THz spectral range. T2 - 2020 45th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) CY - Buffalo, NY, USA DA - 08.11.2020 KW - THz radiation KW - Total transmittance reflection technique KW - Etalon effects PY - 2020 SN - 978-1-7281-6620-9 DO - https://doi.org/10.1109/IRMMW-THz46771.2020.9370451 SN - 2162-2035 SN - 2162-2027 SP - 1 PB - IEEE CY - Buffalo, NY AN - OPUS4-56943 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schade, U. A1 - Puskar, L. A1 - Golnak, R. A1 - Veber, A. A1 - Beckmann, Jörg T1 - Infrared Attenuate Total Reflection Cell with a Functionalized Surface N2 - ATR cell utilizing chips from silicon wafers is discussed. The cell can be used for wet-chemical analysis on functionalized surfaces. Here, silicon chips are exemplarily "functionalized" by silica layers to provide a hydrophilic or hydrophobic ATR surface in-situ. T2 - 48th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz) CY - Montreal, Quebec, Canada DA - 17.09.2023 KW - THz radiation KW - ATR KW - FTIR PY - 2023 DO - https://doi.org/10.1109/IRMMW-THz57677.2023.10298918 SP - 1 PB - IEEE CY - New York, NY AN - OPUS4-59326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Biyikal, Mustafa A1 - Rurack, Knut T1 - Development of a Lab-on-a-Chip for the Detection of Nerve Agents with a Handheld Device N2 - The development of a Lab-on-a-Chip (LoC) is presented, which can detect reactive phosphorous compounds in the gas phase in combination with an optochemical hand-held sensor. The LoC prototype contains three pairs of sensing materials containing fluorescent indicator dyes in various carrier materials. By measuring the fluorescence response to phosphoryl chloride, a surrogate compound, the detection of chemical warfare agents (CWAs) in gas phase becomes possible within seconds, introducing a novel approach to CWA detection. T2 - 2023 IEEE SENSORS Conference CY - Vienna, Austria DA - 29.10.2023 KW - Lab-on-a-Chip KW - Nerve agents KW - Hand-held KW - Fluorescence KW - Toxic industrial chemicals PY - 2023 UR - https://ieeexplore.ieee.org/document/10325263 SN - 979-8-3503-0387-2 DO - https://doi.org/10.1109/SENSORS56945.2023.10325263 SP - 1 EP - 4 PB - IEEE CY - New York AN - OPUS4-59367 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Ritz, Sebastian A1 - Loewe, Anna A1 - Bauer, Jan T1 - Specialties of HAZID-Study for Large Unmanned Underwater Vehicles N2 - This paper scopes the specialties of a hazard identification study for large and extra-large unmanned undersea vehicles (UUVs). A generic node/function structure is derived from different large and extra-large UUV designs, partially own vehicle designs from research projects, and partially from commercial vehicles. For each node, a short overview of its components and the proper function or operations is defined. A set of guide words is used to prompt a hazard discussion for each node, which identifies unwanted functions, resulting in potential hazards and unmitigated consequences. Related to the SafeMASS-Report from DNV, this work concentrates on selected topics of the bridge-related function on voyage, control & monitoring, and abnormal situations. For unmanned vehicles without any person on board, these three topics become more important for underwater vehicles with very limited connectivity or temporary disruptions of communication whereby an operator in a remote-control center could only be provided with rough vehicle or mission states. Therefore, vehicle control, whether in hard- or software, must handle most tasks belonging to the considered functions automatically or autonomously. Hence, the most appropriate reactions of the system to unwanted system behavior must be implemented. This HAZID study could, on the one hand, be used as background for such an implementation, and on the other hand, it is used to verify the implemented actions on the risks and hazards. T2 - OCEANS 2023 - Limerick CY - Limerick, Ireland DA - 05.06.2023 KW - Autonomous underwater vehicles KW - HAZID KW - Risk-based design KW - Safety KW - Cyber security PY - 2023 DO - https://doi.org/10.1109/OCEANSLimerick52467.2023.10244358 SP - 1 EP - 10 PB - IEEE AN - OPUS4-59099 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Richter, Matthias A1 - Horn, Wolfgang A1 - Jann, Oliver A1 - Juritsch, Elevtheria A1 - Klinge, A. A1 - Roswag, E. A1 - Fontana, Patrick A1 - Miccoli, Lorenzo T1 - Indoor air emission tests of natural materials N2 - Emissions of building materials might have negative impact on human health and well-being. In the EU-funded research project H-House more than 30 natural materials (earthen dry boards and plasters, bio-based insulation materials made of wood, flax, reed, straw, etc.) used for renovation and refurbishment were tested regarding emissions of VOC, formaldehyde and radon. Different to ordinary emission tests on single materials this study focuses on the emissions from complete wall assemblies. Therefore, specially designed test chambers were used allowing the compounds to release only from the surface of the material facing indoors. The testing parameters were chosen in order to simulate model room conditions. The emission results were finally evaluated using the AgBB evaluation scheme, a procedure currently applied for the approval of flooring materials in Germany. T2 - 1st ICBBM - International conference on bio-based building materials CY - Clermont-Ferrand, France DA - 22.06.2015 KW - Emission testing KW - Natural materials KW - VOC KW - Formaldehyde KW - Radon PY - 2015 SN - 978-2-35158-154-4 SP - 641 EP - 643 AN - OPUS4-33609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg A1 - Becker, Ben A1 - Duffner, Eric A1 - Gregor, Christian A1 - Saul, Herbert A1 - Schoppa, André T1 - Composite gas cylinders - probabilistic analysis of minimum load cycle requirements N2 - Composite materials show a degradation of properties depending on Service life. This creates the necessity to find tailored methods to determine strength and residual strength of composite cylinders. The determination can be done e.g. by load cycles tests. The result needs a Statistical assessment for the precise description of strength. Especially the Statistical assessment of load cycle strength properties has a high uncertainty. It is unclear if a Log-Normal distribution, a WEIBULL distribution or others, describe the scatter behaviour of residual strength properties correctly. Distribution functions aim at approximating the frequency of occurrence of residual load cycle strength for high survival rates. An assumption has to be found and confirmed to prevent overestimation of reliability. T2 - ICHS2015 - 6th International conference on hydrogen safety CY - Yokohama, Japan DA - 19.10.2015 KW - Failure rate KW - Confidence level KW - Scatter KW - StorHy KW - Sample performance chart PY - 2015 SN - 978-2-9601366-1-6 SP - 1 EP - 14 AN - OPUS4-34804 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krankenhagen, Rainer A1 - Altenburg, Simon ED - Bison, P. ED - Burleigh, D. T1 - Direct comparison of two pyrometers and a low-cost thermographic camera for time resolved LWIR temperature measurements N2 - Contactless temperature sensing is state of the art and essential part of countless applications in the field of process control and automation. This contribution presents the case of a nondestructive thickness measurement method for polymeric coatings on concrete ground. Two pyrometers and a low-cost infrared camera were taken into account. The particular measurement results were compared with those of a more sophisticated infrared camera. It was found that the low-cost infrared camera has a lower noise level than the pyrometers, even for a single pixel. The opportunity to average over a large number of pixels and to establish a bias correction enables a further noise reduction by almost factor of 10. Furthermore, the temporal resolution of the infrared camera was investigated by means of a well-defined thermal oscillation. It could be demonstrated that the averaged time stamps are correct and the requirement of a Minimum framerate of 50 Hz is met. Finally, the temperature transient on a polymer coated concrete block during and after a 10 s heating period was recorded with a pyrometer and the infrared camera. This experiment confirmed the suitability of the camera for the intended measurement method. T2 - Thermosense: Thermal Infrared Applications CY - Anaheim, CA, USA DA - 10.04.2017 KW - Contactless temperature measurement KW - Layer thickness KW - Pyrometer KW - Infrared camera KW - Nondestructive testing PY - 2017 SN - 978-1-5106-0929-7 SN - 978-1-5106-0930-3 DO - https://doi.org/10.1117/12.2261074 SN - 0277-786X SN - 1996-756X VL - 10214 SP - Article 1021414, 1 EP - 10 AN - OPUS4-40291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Scheidemann, Robert A1 - Qiao, Linan A1 - Müller, Karsten T1 - Comparison of experimental results and numerical simulations of penetration tests with damping concrete N2 - The shock absorbing material damping concrete is for the foundation in dry interim storage facilities for radioactive waste in Germany. In case of a potential cask drop damping concrete minimizes the mechanical loads to the cask. In course of safety analyzes this accident scenario is considered by numerical simulations using the finite element method. To get reliable results of numerical simulations a suitable material model is needed to take the characteristics of damping concrete into account. Due to the lack of sufficient material knowledge a research project was started to characterize the material’s behavior under different load conditions. This paper presents the test program to analyze the material behavior of damping concrete which is characterized by large volume change and strain rate hardening dependence. The determined Parameters were used to adapt an existing material model of the FE-code ABAQUS®. This model has to handle the mechanical damage behavior of damping concrete which occurs under compression and shear loads during a potential cask drop. To verify the material model numerical simulations are compared with dynamic penetration tests, which were conducted with specimens assembled similar to the real application of the damping concrete footings. The transferability of the material model to a real accident scenario was verified by a drop test with a full-scale cask on a damping concrete footing. T2 - ASME 2017 Pressure Vessels & Piping Conference (PVP2017) CY - Waikoloa, Hawaii, USA DA - 16.07.2017 KW - Drop test KW - Damping concrete KW - Cask KW - Material model PY - 2017 SN - 978-0-7918-5802-8 VL - 7 SP - Article UNSP V007T07A034, 1 EP - 6 PB - The American Society of Mechanical Engineers CY - New York AN - OPUS4-44042 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schumacher, David A1 - Meyendorf, N. A1 - Hakim, I. A1 - Ewert, Uwe ED - Chimenti, D. E. ED - Bond, L. J. T1 - Defect recognition in CFRP components using various NDT methods within a smart manufacturing process N2 - The manufacturing process of carbon fiber reinforced polymer (CFRP) components is gaining a more and more significant role when looking at the increasing amount of CFRPs used in industries today. The monitoring of the manufacturing process and hence the reliability of the manufactured products, is one of the major challenges we need to face in the near future. Common defects which arise during manufacturing process are e.g. porosity and voids which may lead to delaminations during operation and under load. To find irregularities and classify them as possible defects in an early stage of the manufacturing process is of high importance for the safety and reliability of the finished products, as well as of significant impact from an economical point of view. In this study we compare various NDT methods which were applied to similar CFRP laminate samples in order to detect and characterize regions of defective volume. Besides ultrasound, thermography and eddy current, different X-ray methods like radiography, laminography and computed tomography are used to investigate the samples. These methods are compared with the intention to evaluate their capability to reliably detect and characterize defective volume. Beyond the detection and evaluation of defects, we also investigate possibilities to combine various NDT methods within a smart manufacturing process in which the decision which method shall be applied is inherent within the process. Is it possible to design an in-line or at-line testing process which can recognize defects reliably and reduce testing time and costs? This study aims to show up opportunities of designing a smart NDT process synchronized to the production based on the concepts of smart production (Industry 4.0). A set of defective CFRP laminate samples and different NDT methods were used to demonstrate how effective defects are recognized and how communication between interconnected NDT sensors and the manufacturing process could be organized. T2 - 44TH ANNUAL REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION CY - Provo, Utah, USA DA - 16.07.2017 KW - Carbon fiber reinforced polymers KW - Non-destructive testing KW - Smart industry (4.0) KW - Ultrasound KW - Laminography KW - Serial sectioning KW - Computed tompgraphy PY - 2018 SN - 978-0-7354-1644-4 DO - https://doi.org/10.1063/1.5031521 SN - 0094-243X VL - 1949 SP - UNSP 020024, 1 EP - 11 PB - AIP Publishing AN - OPUS4-44773 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Prasetiadi, A. E. A1 - Jost, M. A1 - Schulz, Bärbel A1 - Quibeldey, M. A1 - Rabe, Torsten A1 - Follmann, R. A1 - Jakoby, R. T1 - Liquid-Crystal-Based Amplitude Tuner Fabricated N2 - A 30GHz liquid-crystal-based amplitude tuner is proposed for the first time. The amplitude of a signal can be controlled by using the interference principle. An input signal is divided into a tunable liquid crystal phase shifter and a fixed transmission line. Later, the divided signals are combined together at the output port. The output amplitude depends on the phase difference between the tunable and the fixed line. The low temperature co-fired ceramic technology is utilized to fabricate the device. The measurement shows an attenuation range of 11 dB to 30 dB with a maximum biasing voltage of 100V. T2 - 12th European Microwave Integrated Circuits Conference CY - Nürnberg, Germany DA - 09.10.2017 KW - LTCC technology KW - Liquid crystals KW - RF components PY - 2017 SN - 978-2-87487-048-4 SN - 2325-0305 SP - 345 EP - 348 PB - IEEE AN - OPUS4-44752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Prasetiadi, A .E. A1 - Jost, M. A1 - Schulz, Bärbel A1 - Quibelday, M. A1 - Rabe, Torsten A1 - Follmann, R. A1 - Jakoby, R. T1 - Liquid-Crystal-Based Amplitude Tuner Fabricated N2 - 30GHz liquid-crystal-based amplitude tuner is proposed for the first time. The amplitude of a signal can be controlled by using the interference principle. An input Signal is divided into a tunable liquid crystal phase shifter and a fixed transmission line. Later, the divided signals are combined together at the output port. The output amplitude depends on the phase difference between the tunable and the fixed line. The low temperature co-fired ceramic technology is utilized to fabricate the device. The measurement shows an attenuation range of 11 dB to 30 dB with a maximum biasing voltage of 100V. T2 - 47th European Microwave Conference CY - Nürnberg, Germany DA - 10.10.2017 KW - LTCC technology KW - Liquid crystals KW - RF components PY - 2017 SN - 978-2-87487-047-7 SN - 2325-0305 SP - 1085 EP - 1088 PB - IEEE AN - OPUS4-44753 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Jüngert, A. A1 - Dugan, S. A1 - Homann, Tobias A1 - Mitzscherling, Steffen A1 - Prager, Jens A1 - Pudovikov, S. A1 - Schwender, T. T1 - Advanced ultrasonic techniques for nondestructive testing of austenitic and dissimilar welds in nuclear facilities N2 - Austenitic stainless steel welds as well as dissimilar metal welds with nickel alloy filler material, used in safety relevant parts of nuclear power plants, still challenge the ultrasonic inspection. The weld material forms large oriented grains which lead on the one hand to high sound scattering and on the other hand – to inhomogeneity and to the acoustic anisotropy of the weld structure. The ultrasonic wave fronts propagate not linearly, as in ferritic weld joints, but along the curves, which depend on the specific grain structure of the weld. Due the influence of these phenomena, it is difficult to analyze the inspection results and to classify the ultrasonic indications, which could be both from the weld geometry and from the material defects. A correct flaw sizing is not possible. In an ongoing research project, different techniques to improve the reliability of ultrasonic testing at these kinds of welds are investigated. In a first step (in the previous research project) two ultrasonic inspection techniques were developed and validated on plane test specimens with artificial and realistic flaws. In the ongoing project, these techniques are applied to circumferential pipe welds with longitudinal and transverse flaws. The technique developed at the Federal Institute for Materials Research and Testing (BAM) in Germany uses a combination of ray tracing and synthetic aperture focusing technique (SAFT). To investigate the unknown grain structure, the velocity distribution of weld-transmitting ultrasound waves is measured and used to model the weld by ray tracing. The second technique, developed at the Fraunhofer Institute for Nondestructive Testing (IZFP) in Germany, uses Sampling Phased Array (Full Matrix Capture) combined with the reverse phase matching (RPM) and the gradient elastic constant descent algorithm (GECDM). This inspection method is able to estimate the elastic constants of the columnar grains in the weld and offers an improvement of the reliability of ultrasonic testing through the correction of the sound field distortion. The unknown inhomogeneity and anisotropy are investigated using a reference indication and the special optimization algorithm. Both reconstruction techniques give quantitative inspection results and allow the defect sizing. They have been compared to conventional ultrasonic testing with techniques, which are state of the art for components in nuclear power plants. The improvement will be quantified by the comparison of the probability of detection (POD) of each technique. T2 - 44th Annual Review of Progress in Quantitative Nondestructive Evaluation CY - Utah Valley Convention Center, Provo, Utah, USA DA - 15.07.2017 KW - Austenitic stainless steel KW - Nuclear power plants KW - Dissimilar welds KW - Nondestructive testing KW - Ultrasonic testing PY - 2018 SN - 978-0-7354-1644-4 SN - 0094-243X VL - 1949 SP - UNSP 110002, 1 EP - 9 AN - OPUS4-44148 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Otremba, Frank A1 - Romero-Navarrete, José A. T1 - A testing rig to study vehicle-track interaction during turning N2 - A testing rig for the measurement of the dynamic loads on the rails due to cargo sloshing,has been proposedin this paper. The system represents a scale-down approach that simulates astraightening maneuver of the railway car after negotiating a turn. As part of the experimental effort, a mathematical model was developed that, oncevalidated, will provide more insights about the potential effect of many other cardesign factors, on the level of stress developed in the raildue to the sloshing cargo.A fundamental output from the testing, will be the objective comparison between the railloads due toa sloshing and a non-sloshing cargo, together with a validated model that wouldallow parametric studies in relation withthe potential effect,of several track and carproperties,on the magnitude of the sloshing forces on the rail. T2 - IEEE/ASME Joint Rail Conference CY - Pittsburgh, PA, USA DA - 18.04.2018 KW - Testing KW - Rig KW - Vehicle-Track KW - Interaction PY - 2018 SP - 1 EP - 6 PB - ASME AN - OPUS4-44816 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hakim, I. A1 - Schumacher, David A1 - Sundar, V. A1 - Donaldson, S. A1 - Creuz, A. A1 - Schneider, R. A1 - Keller, J. A1 - Browning, C. A1 - May, D. A1 - Abo Ras, M. A1 - Meyendorf, N. ED - Chimenti, D. E. ED - Bond, L. J. T1 - Volume imaging NDE and serial sectioning of carbon fiber composites N2 - A composite material is a combination of two or more materials with very different mechanical, thermal and electrical properties. The various forms of composite materials, due to their high material properties, are widely used as structural materials in the aviation, space, marine, automobile, and sports industries. However, some defects like voids, delamination, or inhomogeneous fiber distribution that form during the fabricating processes of composites can seriously affect the mechanical properties of the composite material. In this study, several imaging NDE techniques such as: thermography, high frequency eddy current, ultrasonic, x-ray radiography, x-ray laminography, and high resolution x-ray CT were conducted to characterize the microstructure of carbon fiber composites. Then, a 3D analysis was implemented by the destructive technique of serial sectioning for the same sample tested by the NDE methods. To better analyze the results of this work and extract a clear volume image for all features and defects contained in the composite material, an intensive comparison was conducted among hundreds of 3D-NDE and multi serial sections’ scan images showing the microstructure variation. T2 - 44TH ANNUAL REVIEW OF PROGRESS IN QUANTITATIVE NONDESTRUCTIVE EVALUATION CY - Provo, Utah, USA DA - 16.07.2017 KW - Carbon fiber reinforced polymers KW - Non-destructive testing KW - Thermography KW - Eddy current KW - Ultrasound KW - X-ray radiography KW - X-ray laminography KW - X-ray computed tomography KW - Serial sectioning PY - 2018 DO - https://doi.org/10.1063/1.5031590 VL - 1949 SP - 120003-1 EP - 120003-10 PB - AIP Publishing AN - OPUS4-45173 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -