TY - CONF A1 - Orellana Pérez, Teresa A1 - Völzke, Holger A1 - Wolff, Dietmar A1 - Zencker, Uwe T1 - Cladding considerations at BAM regarding extended storage spent fuel N2 - With the clear expectation of the need for extending spent fuel storage in Germany beyond the initial license period of maximum 40 years additional material data and knowledge about the long term performance and integrity of casks and internals like fuel rods will be required to meet major safety goals and regulatory requirements. Based on a broad knowledge base about fuel cladding behavior, degradation mechanisms and related potential failure mechanisms, e. g. induced by reoriented Hydride precipitation, as illustrated in this paper, a specific gap analyses for the German situation regarding fuel conditions and cladding materials should identify the specific knowledge gaps to be addressed and closed in the near future. This is of specific interest as all spent fuel assemblies are going to be transferred to dry cask storage with the next decade and as a consequence of the German nuclear phase-out decision. Within several decades, BAM as a Federal materials research institute gathered a broad range of expertise in the safety evaluation of materials, components and casks under operational and accidental thermal and mechanical conditions. This paper elucidates selected Basic considerations regarding technical and scientific knowledge about the long term aging performance and potential failure mechanisms of fuel cladding materials. Under consideration of the national R&D funding policy which has been adapted to the extended interim storage or pre-disposal needs and the competences of BAM, its future R&D strategy is explained and some R&D objectives have already been identified. BAM will continue and expand ist engagement in the area of investigating fuel cladding material behavior in the long term and developing validated simulation and analyses tools in collaboration with national and international partners. R&D outcomes shall improve the knowledge-base to close identified knowledge gaps in the area of demonstrating fuel cladding integrity and to provide crucial information with regard to future safety assessments for the extended interim spent fuel storage. T2 - 16th International High -Level Radioactive Waste Management Conference (IHLRWM 2017) CY - Charlotte, NC, USA DA - 09.04.2017 KW - Spent fuel KW - Storage KW - Fuel cladding PY - 2017 SP - 718 EP - 725 AN - OPUS4-40412 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bresch, Sophie T1 - Druckunterstützte Sinterung von Calciumcobaltitfolien N2 - Calcium cobaltite Ca3Co4O9 is a promising p-type oxide thermoelectric material for applications between 600 °C and 900 °C in air. The properties and the morphology of Ca3Co4O9 are strongly anisotropic because of its layered crystal structure. By aligning the plate-like grains, the anisotropic properties can be assigned to the component. Hot-pressing of tablets is a well-known technology for grain alignment of Ca3Co4O9 and increases the thermoelectric properties in a/b-direction remarkably [1-3]. However, hot-pressing of tablets is limited by the tablet size. An interesting alternative for larger components is the pressure assisted sintering of panels from tape casted layers. Tape casting already leads to grain orientation during green body forming. By combining tape casting and pressure assisted sintering (50 kN maximum force) of Ca3Co4O9, high densities and high thermoelectric properties can be reached for large components up to 200 mm edge length. The morphology of Ca3Co4O9-grains can be designed by doping as well as by varying the powder synthesis conditions. For example Bi-doping increases the anisotropy of the grains, and reaction sintering of uncalcined powder leads to a fine grained microstructure and increases the electrical conductivity for pressure-less sintered specimens. Doped and undoped Ca3Co4O9 powders were successfully tape cast with the doctor blade technique. Several layers of tape were stacked and laminated to 7 cm x 7 cm panels. These panels were sintered in a LTCC sintering press with combined in-situ shrinkage measurement. Pressure-less sintered panels from undoped powder have a 2.5 times higher electrical conductivity at room temperature than dry-pressed test bars with randomly orientated particles. By applying a uniaxial pressure of 10 MPa during sintering, the electrical conductivity (σ25°C=15000 S/m) increases by the factor of 6 compared to the pressure-less sintered panels, which is in good accordance to the values reported in literature for conventional hot pressing [1, 3]. It is not possible to assign the increased anisotropy of Ca2.7Bi0.3Co4O9 to the pressure-assisted sintered panels, as Bi leads to an abnormal grain growth (up to 500 µm) with randomly oriented grains. This decreases the electrical conductivity (σ25°C=5000 S/m). Such an abnormal grain-growth is reported for Bi over-doped Ca3Co4O9 [4] but not because of hot-pressing. N2 - Calciumcobaltit ist eines der vielversprechendsten thermoelektrischen Oxide, welche zur direkten Wärmerückgewinnung genutzt werden können. Calciumcobaltit weist sowohl eine anisotrope Partikelform als auch anisotrope thermoelektrische Eigenschaften auf. Durch gezielte Ausrichtung der Partikel mittels Foliengießens und druckunterstützter Sinterung kann diese Anisotropie gezielt auf ein Bauteil übertragen werden. Die Partikelmorphologie kann durch Dotierung und Kalzinierung beeinflusst werden. Verschiedene Calciumcobaltitpulver wurden druckgesintert und das Gefüge sowie die thermoelektrischen Eigenschaften untersucht. Die Dotierung mit Bismut führte zu einer Verschlechterung der elektrischen Leitfähigkeit bei druckgesinterten Proben im Gegensatz zu undotierten Pulvern. T2 - Funktionsmaterialien - Lehrstuhlseminar CY - Bayreuth, Germany DA - 02.06.2017 KW - Thermoelectrics KW - Calcium cobaltite KW - Pressure assisted sintering KW - Druckunterstützte Sinterung KW - Calciumcobaltit KW - Thermoelektrika PY - 2017 AN - OPUS4-40467 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Andree, Stefan T1 - Production of precursors for micro-concentrator solar cells using femtosecond Laser-Induced Forward Transfer N2 - Indium is a constituent of copper-indium-gallium-diselenide (CIGSe), which is an excellent absorber material for highly-efficient thin film solar cells but a rare element. A micro-concentrator solar cell design can achieve indium saving along with increased solar cell conversion efficiency. In such a solar cell architecture the CIGSe material is arranged in micrometer sized islands in contrast to the deposition of a thin layer used in standard cells. In this paper, the production of spatially arranged precursor islands consisting mainly of indium using laser-induced forward transfer (LIFT) is presented. The donor is a glass substrate (150 µm thick) coated with layers of copper (20-150 nm) and indium (200-1000 nm). The receiver is an 800 nm thick molybdenum film on glass intended as back contact for CIGSe solar cells. Islands of the donor material are successfully transferred via LIFT by employing 30-fs laser pulses with 800 nm wavelength and 60 µm focal spot diameter. The spacing between donor and receiver is fixed at 150 µm and the material transfer is performed by a single pulse for each precursor island. The transferred material is characterized by scanning electron and optical microscopy, profilometry and energy dispersive X-ray analyses. Matrices of copper-indium precursors can be transferred in a spatial arrangement adapted to the geometry of micro lens arrays needed for micro-concentrator solar cells. T2 - European Materials Research Society (EMRS) Spring Meeting 2017, Symposium X “New frontiers in laser interaction: from hard coatings to smart materials” CY - Strasbourg, France DA - 22.05.2017 KW - Copper indium gallium diselenide (CIGSe) KW - Indium KW - Laser-induced forward transfer (LIFT) KW - Femtosecond laser KW - Micro-concentrator solar cell PY - 2017 AN - OPUS4-40433 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mitzscherling, Steffen T1 - Verbesserung und Qualifizierung der Ultraschallprüfung von Mischnähten im Primärkreis von KKW N2 - Die im Primärkreislauf von Kernkraftwerken anzutreffenden austenitischen Schweiß- und Mischnähte sind nicht nur extrem sicherheitsrelevant, sondern stellen auch sehr hohe Anforderungen an die Materialprüfung. Neben der eingeschränkten Zugänglichkeit ist das makroskopische Gefüge der Schweißnaht für die Prüfung mit Ultraschall von höchster Bedeutung. Um Materialfehler zuverlässig in Position und Größe bestimmen zu können, müssen die Kornorientierungen und die elastischen Konstanten des anisotropen Schweißnahtgefüges bekannt sein. Für die bildgebende Darstellung möglicher Materialfehler kommen folgende Arbeitsschritte zum Einsatz: Zunächst wird die Schweißnaht durchschallt, um mit einem inversen Verfahren wichtige Schweißnahtparameter wie beispielsweise die Kornorientierung bestimmen zu können. Auf der Basis dieser Parameter werden im nächsten Schritt die Schallwege mittels Raytracing (RT) simuliert. Zuletzt werden dieser RT-Simulation die Messdaten (A-Scans) von verschiedenen Sender- und Empfängerpositionen zugeordnet und nach der SAFT-Methode (Synthetic Aperature Focusing Technique) zeitaufgelöst überlagert. Die Kombination aus inversem Verfahren, RT und SAFT gewährleistet auch in anisotropen Werkstoffen eine ortsrichtige Visualisierung der Fehler. Wir erläutern diese drei Verfahren und stellen die Prüfanordnung von Prüfkörpern mit künstlichen Testfehlern vor. Messdaten sowie deren Auswertung werden mit den Ergebnissen einer CIVA-Simulation verglichen. T2 - DGZfP-Jahrestagung 2017 CY - Koblenz, Germany DA - 22.05.2017 KW - Zerstörungsfreie Prüfung KW - Ultraschall KW - SAFT KW - Schweißnaht KW - Austenit PY - 2017 AN - OPUS4-40434 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wille, Frank A1 - Linnemann, Konrad A1 - Ballheimer, Viktor A1 - Rolle, Annette T1 - Assessment approaches of mechanical behavior of SNF under transport package test conditions N2 - German packages for the transport of spent nuclear fuel are assessed with respect to specific transport conditions which are defined in the safety regulations of the International Atomic Energy Agency. In general, gastight fuel rods constitute the first barrier of the containment system. The physical state of the spent fuel and the fuel rod cladding as well as the geometric configuration of the fuel assemblies are important inputs for the evaluation of the package safety under transport conditions. The objective of this paper is to discuss the methodologies accepted by German authority BAM for the evaluation of spent fuel behavior within the package design approval procedure. Specific test conditions will be analyzed 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, which can cause release of gas, volatiles, fuel particles or fragments, have to be properly considered in these assumptions. The package as a mechanical system is characterized by a complex set of interactions, e.g. between the fuel rods within the assembly as well as between the fuel assemblies, the basket, and the cask containment. This complexity together with the limited knowledge about the material properties and the variation of the fuel assemblies regarding cladding material, burn-up and the operation history makes an exact mechanical analysis of the fuel rods nearly impossible. The application of sophisticated numerical models requires extensive experimental data for model verification, which are in general not available. 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, and require a conservative approach. In this context some practical approaches based on experiences by BAM within safety assessment of packages for transport of spent fuel will be discussed. Ongoing research activities to investigate SNF mechanical behavior in view of gas and fissile material release under transport loads are presented. T2 - International High-Level Radioactive Waste Management Conference, IHLRWM 2017 CY - Charlotte, NC, USA DA - 09.04.2017 KW - Brennelementverhalten KW - Spent fuel behavior KW - Hüllrohr KW - Kritikalität KW - Aktivitätsfreisetzung KW - Mechanisches Verhalten KW - Cladding KW - Criticality PY - 2017 SP - 472 EP - 475 AN - OPUS4-39898 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wille, Frank T1 - Assessment approaches of mechanical behavior of SNF under transport package test conditions N2 - German packages for the transport of spent nuclear fuel are assessed with respect to specific transport conditions which are defined in the safety regulations of the International Atomic Energy Agency. In general, gastight fuel rods constitute the first barrier of the containment system. The physical state of the spent fuel and the fuel rod cladding as well as the geometric configuration of the fuel assemblies are important inputs for the evaluation of the package safety under transport conditions. The objective of this paper is to discuss the methodologies accepted by German authority BAM for the evaluation of spent fuel behavior within the package design approval procedure. Specific test conditions will be analyzed 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, which can cause release of gas, volatiles, fuel particles or fragments, have to be properly considered in these assumptions. The package as a mechanical system is characterized by a complex set of interactions, e.g. between the fuel rods within the assembly as well as between the fuel assemblies, the basket, and the cask containment. This complexity together with the limited knowledge about the material properties and the variation of the fuel assemblies regarding cladding material, burn-up and the operation history makes an exact mechanical analysis of the fuel rods nearly impossible. The application of sophisticated numerical models requires extensive experimental data for model verification, which are in general not available. 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, and require a conservative approach. In this context some practical approaches based on experiences by BAM within safety assessment of packages for transport of spent fuel will be discussed. Ongoing research activities to investigate SNF mechanical behavior in view of gas and fissile material release under transport loads are presented. T2 - International High-Level Radioactive Waste Management Conference, IHLRWM 2017 CY - Charlotte, NC, USA DA - 09.04.2017 KW - Spent fuel KW - Cladding failure KW - Criticality analysis KW - Encapsulation PY - 2017 AN - OPUS4-39908 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittrich, Matthias T1 - Legacy waste containers for low and intermediate level radioactive waste in Germany – current situation and challenges N2 - Low and intermediate level radioactive waste has been produced in Germany for several decades. While a part of the waste had been deposited in the Morleben repository and the Asse mine which have been operated for just a limited period of time, the major amount is conditioned and packaged in temporarily stored waste containers. Those containers are designated for final disposal in the KON-RAD repository being currently under construction and expected to start opera-tion in 2022. As a consequence, an assessment of the waste container documen-tation and safety is strongly needed to receive an approval for the Konrad reposi-tory. This requalification is challenging because those old containers have to meet the same safety requirements as new containers. T2 - Waste Management Symposia 2017 CY - Phoenix, USA DA - 05.03.2017 KW - Legacy waste container KW - Konrad PY - 2017 AN - OPUS4-39872 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Komann, Steffen T1 - German concept to ensure transportability of SNF packages after interim storage N2 - In Germany the concept of dry interim storage of spent fuel in dual purpose metal casks is implemented, currently for periods of up to 40 years. The casks being used have an approved transport package design in accordance with the international IAEA transport regulations as well. The storage of spent nuclear fuel and high-level waste in dual purpose casks (DPC) is related with the challenge of maintaining safety for transportation over several decades of storage. Besides consideration of aging mechanisms by appropriate design, material selection and operational controls to assure technical reliability by aging management measures, an essential issue is the continuous control and update of the DPC safety case. Not only the technical objects are subject of aging but also the safety demonstration basis is subject of “aging” due to possible changes of regulations, standards and scientific/technical knowledge. To ensure a safe transport in future to a destination which is not known yet (because of not yet existing repository sites) periodical reviews of the Package Design Safety Report (PDSR), in connection with periodic renewals of package design approval certificates, have to be carried out. T2 - International High-Level Radioactive Waste Management Conference, IHLRWM 2017 CY - Charlotte, NC, USA DA - 09.04.2017 KW - Dual purpose casks KW - Long time storage KW - Aging management KW - Approval certificate PY - 2017 AN - OPUS4-39916 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Komann, Steffen A1 - Wille, Frank A1 - Schönfelder, Thorsten T1 - German concept to ensure transportability of SNF packages after interim storage N2 - In Germany the concept of dry interim storage of spent fuel in dual purpose metal casks is implemented, currently for periods of up to 40 years. The casks being used have an approved transport package design in accordance with the international IAEA transport regulations as well. The storage of spent nuclear fuel and high-level waste in dual purpose casks (DPC) is related with the challenge of maintaining safety for transportation over several decades of storage. Besides consideration of aging mechanisms by appropriate design, material selection and operational controls to assure technical reliability by aging management measures, an essential issue is the continuous control and update of the DPC safety case. Not only the technical objects are subject of aging but also the safety demonstration basis is subject of “aging” due to possible changes of regulations, standards and scientific/technical knowledge. To ensure a safe transport in future to a destination which is not known yet (because of not yet existing repository sites) periodical reviews of the Package Design Safety Report (PDSR), in connection with periodic renewals of package design approval certificates, have to be carried out. T2 - International High-Level Radioactive Waste Management Conference, IHLRWM 2017 CY - Charlotte, NC, USA DA - 09.04.2017 KW - Dual purpose casks KW - Interim storage KW - Transportability PY - 2017 SP - 476 EP - 481 AN - OPUS4-39919 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlichting, S. A1 - Hönig, Gerald T1 - Tuning of the quantum-confined Stark effect in wurtzite [0001] nanostructures by the internal-field-guarded-active-region design N2 - In this work we eliminate the QCSE without having any special requirements on the growth procedure or the material. Hönig et al. developed the Internal-Field-Guarded-Active-Region Design (IFGARD), which we experimentally investigate in this work based on GaN/AlN nanodiscs (NDs). T2 - Compound Semiconductor Week 2017 CY - Berlin, Germany DA - 14.05.2017 KW - Halbleiterphysik KW - Nanophysik KW - Optoelektronik KW - Piezopolarisation KW - Spontane Polarisation PY - 2017 AN - OPUS4-40174 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Berger, Anka A1 - Anca-Couce, A. A1 - Dieguez-Alonso, A. A1 - Zobel, N. A1 - Kienzl, N. A1 - Behrendt, F. T1 - Influence of heterogeneous secondary reactions during slow pyrolysis on char oxidation reactivity of woody biomass N2 - The influence of heterogeneous secondary reactions on char oxidation reactivity, which can take place during slow pyrolysis processes in a woody biomass particle, is analyzed in this study. To this end, the oxidative behavior of primary char produced in a thermobalance with initial wood masses of a few milligrams is compared to the behavior of char produced under conditions enhancing secondary reactions, i.e., large particle and bed sizes in fixed-bed reactors. The influence of the Maximum conversion temperature, heating rate, and catalytic effect of inorganics is also studied to compare the effect of each parameter. Results show that a significant reduction in reactivity takes place when char is produced under conditions enhancing These secondary reactions during pyrolysis. The effect is of similar order as the effect as a result of thermal annealing at 900 °C or the catalytic effect of alkali and alkaline earth metals. Therefore, the presence of heterogeneous secondary reactions during pyrolysis should be taken into account in studies addressing biomass char reactivity. Furthermore, it is shown that the reduction of reactivity as a result of secondary reactions is related to neither the loss of oxygen-containing functional groups nor the potential blocking of pores, specially micropores, resulting from the formation of this secondary char. The explanation may, therefore, lie on the deactivation or blocking of active sites by the secondary char. KW - Char conversion KW - Char reactivity KW - Pyrolysis KW - Woody biomass KW - Thermogravimetric analysis KW - TGA PY - 2017 DO - https://doi.org/10.1021/acs.energyfuels.6b02350 SN - 0887-0624 SN - 1520-5029 VL - 31 IS - 3 SP - 2335 EP - 2344 PB - ACS Publications AN - OPUS4-40189 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Feldkamp, Martin A1 - Erenberg, Marina A1 - Nehrig, Marko A1 - Bletzer, Claus A1 - Musolff, André A1 - Wille, Frank A1 - Schönfelder, Thorsten T1 - Aspects of assessment of packages with wood filled impact limiters during fire tests N2 - Packages for the transport of radioactive material are often equipped with impact limiters consisting of wood, encapsulated by steel sheets. These impact limiters shall ensure that the transport casks meet the mechanical and thermal IAEA regulatory test requirements. According to the accident conditions of transport it is mandatory to expose the specimens to a cumulative effect by mechanical and thermal impacts. The mechanical tests consist of a free drop from 9 m onto a flat unyielding target and a 1 m drop onto a puncture bar. After damage caused by mechanical test sequences the package has to withstand a severe fire scenario. Corresponding to the IAEA advisory material it is required that the impact attitudes for the 9 m drop test and for the puncture test have to be such as to produce maximum damage, taking into account the thermal test. Moreover, any damage, which would give rise to increased radiation or loss of containment or affect the confinement system after the thermal test, should be considered. During and following the thermal test, the specimen shall not be artificially cooled and any combustion of materials of the package shall be permitted to proceed naturally. Different works from the French Institute for Radiological Protection and Nuclear Safety (IRSN) and BAM show that additional energy supply from a pre-damaged impact limiter to the cask could occur. This effect should be considered within the safety assessment of the containment. Thermal effects at the closure system of the cask, which might result in an elevated activity release, have to be excluded. BAM conducted small scale tests with wood filled metal buckets showing continuing combustion processes during the cooling down phase. These test results are presented. As not much is known about smouldering processes in wood filled impact limiters, it is highly complex to define pre-damage of impact limiters, which are conservative, regarding the maximum damaging energy flow from the impact limiter to the containment system. More research has to be done to develop models to examine the effects of smouldering impact limiters on the containment of packages for the transport of radioactive material. Aspects of assessment and its difficulties are shown. BAM as a competent authority for the approval of transport casks for radioactive material in Germany operates the test facilities to examine the issue of mechanical damage, combustion and heat transfer for such kind of package systems. For this purpose the knowledge from real drop tests with casks of a mass partly over 100 tons was transferred to a test application. A thermal test will take place with a wood filled test specimen with a diameter of about 2.3 meters. The aim is to understand the phenomena of smouldering under the consideration of relevant regulatory boundary conditions. The process of smouldering is described with regard to the requirements in the thermal assessment of safety of packages for the transport of radioactive material. Requirements concerning the pre-damage of packages for the maximum damage of impact limiters are discussed. Parameters influencing the smouldering process are identified. T2 - WM 2017 Conference CY - Phoenix, AZ, USA DA - 05.03.2017 KW - Fire test KW - Wood KW - Combustion KW - Smouldering KW - Smoldering KW - Impact limiter KW - Shock absorber KW - Thermal test KW - IAEA PY - 2017 SN - 978-0-9828171-6-2 SP - 1 AN - OPUS4-40157 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kuschke, Christian T1 - Standards and Guidelines for Design of Trunnions of RAM Transport Packages N2 - Trunnion systems of packages for the transport of radioactive materials have to guarantee the safe handling of package during crane operations (lifting, tilting) and to secure package tie down to the transport vehicle, if the trunnions are used as attachment points during transport. The design of trunnions is based on IAEA Regulations SSR-6, the supporting Advisory Material SSG-26 and further appropriate technical standards and/or guidelines. For package approval procedures in Germany the guideline BAM GGR 012 has to be applied. If a package is handled inside a german nuclear power plant, the standard KTA 3905 has to be fulfilled additionally. In this paper the requirements of KTA 3905 concerning the trunnion systems as load attaching points (LAP) are discussed in connection with the recommendations in the guideline BAM-GGR 012. This guideline is prepared at BAM Federal Institute for Materials Research and Testing for analysis and assessment of bolted lid and trunnion systems of Type B(U) transport packages. The quality assurance questions concerning trunnion systems are discussed as well. T2 - Waste Management 2017 Conference CY - Phoenix, Arizona, USA DA - 05.03.2017 KW - Trunnions KW - RAM Transport Package PY - 2017 AN - OPUS4-39997 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stengel, Dominik A1 - Bardl, Richard A1 - Kühnel, C. A1 - Großmann, S. A1 - Kiewitt, W. T1 - Accelerated electrical and mechanical ageing tests of high temperature low sag (HTLS) conductors N2 - As part of the Best Paths project, work package 6 of the DEMO #4 combines the R&D tasks for repowering of transmission overhead line corridors. The aim of the presented research work is the electrical and mechanical investigation of high temperature low sag conductors (HTLS) and their respective accessories. In contrast to the conventional ACSR (aluminum conductor steel reinforced) conductors, new material combinations of HTLS technologies result in a better sagging behavior combined with an operation at higher temperatures. Because of missing operational experience, the ageing behavior of HTLS conductor technologies shall be analyzed regarding the operating parameters such as electrical, thermal and mechanical load. T2 - ICOLIM Conference 2017 CY - Strasbourg, France DA - 25.04.2017 KW - High temperature low sag conductors KW - Accelerated ageing KW - Long-term loading PY - 2017 SN - 978-1-5090-5132-8 SP - 1 EP - 6 AN - OPUS4-40040 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bardl, Richard T1 - Accelerated electrical and mechanical ageing tests of high temperature low sag (HTLS) conductors N2 - As part of the Best Paths project, work package 6 of the DEMO #4 combines the R&D tasks for repowering of transmission overhead line corridors. The aim of the presented research work is the electrical and mechanical investigation of high temperature low sag conductors (HTLS) and their respective accessories. In contrast to the conventional ACSR (aluminum conductor steel reinforced) conductors, new material combinations of HTLS technologies result in a better sagging behavior combined with an operation at higher temperatures. Because of missing operational experience, the ageing behavior of HTLS conductor technologies shall be analyzed regarding the operating parameters such as electrical, thermal and mechanical load. T2 - International Conference on Live Maintenance (ICOLIM) 2017 CY - Strasbourg, France DA - 25.04.2017 KW - High temperature low sag conductors KW - Accelerated ageing KW - Long-term loading PY - 2017 AN - OPUS4-40041 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stajanca, Pavol A1 - Krebber, Katerina ED - Chung, Y. ED - Jin, W. ED - Lee, B. ED - Canning, J. ED - Nakamura, K. ED - Yuan, L. T1 - Towards on-line radiation monitoring with perfluorinated polymer optical fibers N2 - Sensitivity of two commercial perfluorinated (PF) polymer optical fibers (POFs) to gamma radiation was measured, compared and exploited for dosimetry purposes. Fiber radiation induced attenuation (RIA) was found to be highly wavelength dependent and pronounced towards the UV part of the spectrum. PF-POFs were shown to be highly radiation sensitive and RIA-based on-line radiation monitoring with sensitivity as high as 135 dBm-1/kGy was demonstrated at 460 nm with co-extruded PF-POF. In addition, thanks to low inherent attenuation in the near-infrared region, possibility of distributed radiation detection with PF-POFs was demonstrated for the first time, utilizing optical time domain reflectometry. T2 - 25th International Conference on Optical Fiber Sensors CY - Jeju, Republic of Korea DA - 24.04.2017 KW - Radiation-induced attenuation KW - Perfluorinated polymer optical fibers KW - Cytop KW - Gamma radiation KW - Optical fiber dosimetry KW - Optical fiber sensors KW - Distributed radiation sensing PY - 2017 SN - 978-1-5090-4850-2 DO - https://doi.org/10.1117/12.2256354 SN - 0277-786X SN - 1996-756X VL - 10323 SP - 103231O-1 EP - 103231O-4 PB - SPIE AN - OPUS4-40323 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stajanca, Pavol T1 - Towards on-line radiation monitoring with perfluorinated polymer optical fibers N2 - Over the last decades, ionizing radiation has been gaining importance in various fields outside the nuclear industry. Among available dosimetry techniques, optical fiber‑based dosimeters (OFDs) offer numerous advantages such as electromagnetic immunity, small dimensions and possibility of remote and real time monitoring. Monitoring of radiation‑induced attenuation (RIA) of the fiber is one of the most straightforward OFD techniques. Compared to silica fibers, large‑diameter multi-mode (MM) polymer optical fibers (POFs) are easy to handle, allow for more economical connectorization and have better biocompatibility. Therefore they may yield cheaper, user-friendlier monitoring systems. In this work, feasibility of RIA-based radiation monitoring with highly sensitive perfluorinated (PF) POFs has been investigated. T2 - 25th International Conference on Optical Fiber Sensors CY - Jeju, Republic of Korea DA - 24.04.2017 KW - Radiation monitoring KW - Perfluorinated polymer optical fibers KW - Cytop KW - Distributed radiation detection PY - 2017 AN - OPUS4-40324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stajanca, Pavol T1 - Polymer optical fibers for sensing applications: ionizing radiation monitoring N2 - In the last decades, considerable attention has been paid to the development of polymer optical fibers (POFs) that may, in certain cases, represent more suitable or cost effective alternative to their glass based counterparts. Due to some of their unique properties, POFs have found their applications in the area of data transmission, lighting as well as optical sensing. Compared to the glass based fiber sensors, POFs are more robust and flexible yielding sensors suitable also for larger strain applications. They have better biocompatibility and are generally more acceptable for medical applications. In addition, POFs can provide higher inherent sensitivity to some of the more alternative measurands such as humidity or ionizing radiation. Over the last three years, BAM’s Division 8.6 has been participating in the European FP7 project “TRIPOD” devoted to the development of POF technology for sensing applications. Project activities and main technological achievements will be reviewed. Special attention will be paid to the utilization of optical fiber sensors in radiation environments. In the recent years, ionizing radiation has found numerous applications also outside the nuclear industry, e.g. in material processing, sterilization or medical applications. With increasing importance of radiation processes, demand for suitable monitoring techniques is rising as well. Among available dosimetry solutions, optical fiber based dosimeters offer numerous advantages such as electromagnetic immunity, small dimensions and possibility of remote and real time monitoring. A concept of attenuation based radiation sensing with perfluorinated POFs will be investigated and presented as a potential candidate for low cost easy to use on line radiation monitoring system. T2 - The Fiber Society 2017 Spring Conference CY - Aachen, Germany DA - 17.05.2017 KW - Polymer optical fibers KW - Fiber Bragg grating sensors KW - Gamma radiation KW - Radiation monitoring PY - 2017 AN - OPUS4-40325 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dittrich, Matthias A1 - Kasparek, Eva-Maria A1 - Völzke, Holger T1 - Legacy waste containers for low and intermediate level radioactive waste in Germany - Actual situation and challenges –17070 N2 - Low and intermediate level radio active waste has been produced in Germany for several decades. While a part of the waste had been deposited in the Morleben repository and the Asse mine which have been operated for just a limited period of time, the major amount is conditioned and packaged in temporarily stored waste containers. Those containers are designated for final disposal in the KONRAD repository being currently under construction and expected to start operation in 2022. As a consequence, an assessment of the waste container documentation and safety is strongly needed to receive an approval for the KONRAD repository. This requalification is challenging because those old containers have to meet the same safety requirements as new containers. T2 - WasteManagement Symposia 2017 CY - Phoenix, USA DA - 05.03.2017 KW - Radioactive waste container KW - Konrad KW - Repository PY - 2017 UR - https://www.xcdsystem.com/wmsym/2017/028.html#17070 SP - Paper 17070, 1 EP - 14 AN - OPUS4-40326 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hoffmann, Mathias T1 - Schmiedestahl als neuer Behälterwerkstoff zur Endlagerung von schwach- und mittelradioaktiven Abfällen für das Endlager Konrad N2 - Durch den Betrieb und den fortschreitenden Rückbau der in Deutschland stationierten Kernkraftwerke und kerntechnischen Anlagen, steigt auf Seiten der Industrie sowie Energieversorgungsunternehmen der Bedarf nach geeigneten Abfallbehältern zur Konditionierung und Entsorgung anfallender schwach- und mittelradioaktiver Abfälle mit vernachlässigbarer Wärmeentwicklung. Deutlich spürbar ist hierbei der Impuls der Hersteller auch Abfallbehälter aus anderen als den bislang verwendeten Werkstoffen wie z. B. Beton, Gusswerkstoff oder Stahlblech zu fertigen. Dabei besteht insbesondere das Interesse an der Herstellung von Konrad-Endlagerbehältern aus Schmiedestahl. Die Verwendung von Schmiedestahl als Behälterwerkstoff ist bereits bei Transport- und Zwischenlagerbehältern für hochradioaktive Abfälle etabliert. Das Material bietet auch für Konrad-Endlagerbehälter aufgrund seiner günstigen Festigkeits- und Zähigkeitseigenschaften in Anbetracht der erhöhten Anforderungen an die Barriereeigenschaften von störfallfesten Behältern der Abfallbehälterklasse II gewisse Vorteile. Denn für Behälter der Abfallbehälterklasse II müssen gemäß Endlagerungsbedingungen und Produktkontrolle über die Abfallbehälterklasse I hinaus zusätzliche Kriterien an die Behälterauslegung zur Erhaltung der Integrität erfüllt werden. Ebenfalls müssen erhöhte Dichtheitskriterien zur Einhaltung zulässiger Radionuklidfreisetzungen während und nach einem mechanischen oder thermischen Störfallszenario eingehalten werden. Die größten Herausforderungen zur Qualifizierung von Schmiedestahlbehältern liegen in der Bewertung der Nachweiskonzepte zur Ermittlung der abdeckenden Fallorientierung und Prüfmusterkonfiguration für den geforderten Fallversuch aus 5 m Höhe. Hierbei ist gemäß Produktkontrolle das Prüfmuster so auszuwählen und zu fertigen, dass es einschließlich seines simulierten Inhalts für die Serienfertigung repräsentativ ist und bei der Fallprüfung der größtmögliche Schaden bezüglich maximaler Kräfte, maximaler Spannungen und maximaler Verformungen erzielt wird. Eine weitere wesentliche Herausforderung ist die Eignungsprüfung des vom Antragsteller ausgewählten konservativ abdeckenden Inventars für die einstündige Brandprüfung bei 800°C, welche die Gesamtheit der kritischen Eigenschaften der für die Serienbehälter vorgesehenen Inhalte, insbesondere Ionenaustauscherharze und Verdampferkonzentrate sowie deren Auswirkung auf die Wärmeverteilung, das Pyrolyseverhalten und den Druckaufbau im Behälter berücksichtigt. Diese Prüfung hat das Ziel, die Erfüllung der Dichtheitskriterien nach einem simulierten thermischen Störfall nachzuweisen. Bis auf einige Ausnahmen existieren in den Endlagerungsbedingungen und Produktkontrolle keine spezifischen Anforderungen an Behälterwerkstoffe. Grundsätzlich dürfen Behälter aus Werkstoffen hergestellt werden, die einzeln und in Ihrer Gesamtheit nachweislich für den Einsatzzweck der Behälter geeignet sind. Diese Anforderungen sind in der Regel dann erfüllt, wenn die verwendeten Schmiedestähle nach allgemein anerkannten Regeln der Technik hergestellt, gefügt und geprüft werden und im Rahmen der Bauartprüfung der Behälter ihre Eignung nachgewiesen werden. Neben den bisher explizit genannten Behälterwerkstoffen Beton, Guss(eisen) und Stahlblech hat das Bundesamt für Strahlenschutz (BfS) auch in Zusammenarbeit mit der BAM Schmiedestahl zusätzlich in die neue Revision der Endlagerungsbedingungen aufgenommen. Hierdurch wird jetzt neu die Option eröffnet ohne gesonderte Zustimmung des BfS, Anträge auf Zulassung von Schmiedestahlbehältern für das Endlager Konrad zu stellen. Hierbei stehen grundsätzlich alle über die Behältergrundtypen in spezifizierten Formen und Abmessungen zur Disposition. Mit diesem Beitrag berichtet die BAM über die aktuellen nationalen und internationalen Bestrebungen Schmiedestahl als Behälterwerkstoff für die Lagerung von mittelradioaktiven Abfällen zu etablieren. Dabei wird auch auf die Besonderheiten eingegangen, denen sich Antragsteller bei der Qualifizierung von derartigen Behältern in der Abfallbehälterklasse II unter Berücksichtigung der in und genannten Anforderungen zu stellen haben. T2 - Kontec 2017 CY - Dresden, Germany DA - 22.03.2017 KW - Schmiedestahl KW - Behälterwerkstoff KW - Endlagerung KW - Abfälle KW - Konrad PY - 2017 AN - OPUS4-40343 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hoffmann, Mathias ED - Kasparek, Eva-Maria ED - Völzke, Holger T1 - Schmiedestahl als neuer Behälterwerkstoff zur Endlagerung von schwach- und mittelradioaktiven Abfällen für das Endlager Konrad T1 - Forged steel as a new container material to the final storage of low- and medium-level radioactive waste for the Konrad repository N2 - Mit diesem Beitrag berichtet die BAM über den Stand der Technik und die bereits existierenden Behälterbauarten für die Lagerung von mittelradioaktiven Abfällen mit Ausblick auf die Vorteile und Anwendungszwecke von Schmiedestahl als bevorzugter Behälterwerkstoff. Aus Sicht der Bundesanstalt für Materialforschung und -prüfung (BAM) wird dargestellt, welche Herausforderungen im Allgemeinen bei der Qualifizierung von Schmiedestahlbehältern existieren und warum diese im Vergleich zu den bislang verwendeten Konstruktionen bevorzugt zur Erfüllung der erhöhten Anforderungen an die Barriereeigenschaften eines Behälters der Abfallbehälterklasse II (ABK II) ausgewählt werden. T2 - Kontec 2017 - 13. Internationales Symposium "Konditionierung radioaktiver Betriebs- und Stilllegungsabfälle" einschließlich 13. Statusbericht des BMBF "Stilllegung und Rückbau kerntechnischer Anlagen" CY - Dresden, Germany DA - 22.03.2017 KW - Schmiedestahl KW - Behälterwerkstoff KW - Endlagerung KW - Abfälle KW - Konrad PY - 2017 SP - Tagungsband, 673 AN - OPUS4-40344 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hübert, Thomas T1 - Hydrogen sensor deployment N2 - Presentation of BAM test facility. Presentation of previous analysis of sensor performance in relation to application requirements and sensor data base. The main topics of sensor metrological, deployment and operational metrics were discussed. T2 - Hydrogen Sensor Workshop CY - Brussels, Belgium DA - 10.05.2017 KW - Hydrogen sensors KW - Sensor deployment PY - 2017 AN - OPUS4-40270 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völzke, Holger A1 - Wolff, Dietmar T1 - Update on the German approach of storing spent nuclear fuel in dual purpose casks until final disposal N2 - The safe and secure long term storage of spent nuclear fuel until its final disposal in a deep geological repository is a corner stone of the German nuclear waste management strategy. So far interim storage licenses are limited to 40 years concerning the initial concept of having a repository available until 2035. But in the meantime the exploration of the designated Gorleben salt dome was finally stopped and a reset of the complete site selection process was concluded by the German Federal parliament and subsequently fixed by law. A 33-member “Commission on the storage of highly radioactive materials” was established in 2014, to elaborate a consent based siting process and to develop criteria for the safe disposal of heat generating waste. The disposal commission agreed and published its final report in 2016. As a major consequence, the necessary timeframe for establishing the final repository is going to be exceeded significantly and with that, an extension of the current dry interim storage in dual purpose casks becomes necessary. This paper explains the major actions to be taken in Germany to address all relevant issues for a future extension of storage licenses beyond the initial timeframe of 40 years. T2 - ANS Conference International High-Level Radioactive Waste Management (IHLRWM) 2017 CY - Charlotte, NC, USA DA - 09.04.2017 KW - Spent Fuel KW - Storage KW - Disposal PY - 2017 AN - OPUS4-40303 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Orellana Pérez, Teresa T1 - Cladding considerations at BAM regarding extended storage of spent fuel N2 - The current German waste management strategy consists of dry interim storage of spent fuel inside dual purpose casks at various sites and its subsequent direct final disposal in a deep geological repository. Interim facilities are licensed for up to 40 years of operation but this storing period will have to be extended until repository site selection and operation is concluded, potentially up to 100 years. In this context, research on long term mechanical behavior of fuel cladding and cask components during extended interim storage and transportation to a final repository are of outmost importance. Barrier properties of the fuel cladding depend on its integrity which is affected over time by thermo-mechanical loads and by microstructure altering including potential embrittlement caused by re-oriented hydride precipitation. Experimental and numerical investigations have been performed by the international research community in order to predict the degree of cladding embrittlement against storage time. Results have shown that embrittlement of cladding materials is governed by the concentration, orientation and size of precipitated hydrides. Nevertheless, the existing variety of fuel materials and assemblies available on the market and the many parameters effecting hydride precipitation do not allow sufficient reliable safety predictions in the long term without further investigation. Thus, knowledge on cladding integrity over storage time and during subsequent transportation is to be gained taking into consideration the relevant fuel and cladding material types as well as cladding temperatures along with peak values during cask drying and cooling rates during storage periods. Expected research results will increase the accuracy of cladding safety analysis. This paper summarizes the current German status regarding extended interim storage and how BAM is going to identify and address potential cladding integrity issues in the long term. T2 - ANS Conference International High-Level Radioactive Waste Management (IHLRWM) 2017 CY - Charlotte, NC, USA DA - 09.04.2017 KW - Spent Fuel Cladding KW - Hydrides KW - Storage PY - 2017 AN - OPUS4-40305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völzke, Holger T1 - Preserving competence in nuclear technology - BAM's contributions N2 - With regard to the nuclear phase-out in Germany preserving competence in nuclear technology is a major challenge. This presentation explains how BAM addresses this issue within its specific tasks, expertise and long term experience on nuclear waste package design testing and safety evaluation. T2 - 48th Annual Meeting on Nuclear Technology (AMNT 2017) CY - Berlin, Germany DA - 16.05.2017 KW - Nuclear Technology KW - Safety KW - Waste Packages KW - Design Testing PY - 2017 AN - OPUS4-40306 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Völzke, Holger T1 - Perspectives on extending interim storage of spent nuclear fuel (beyond the initial license period) N2 - The presentation adddresses the consequences and challenges of the German nuclear phase-out in conjunction with the restart of siting process for a high-level radioactive waste repository. Concerning spent fuel this will lead to extended interim storage periods for the dry storage casks beyond the initial licensing period of 40 years. For extending storage periods additional safety assessments and data about the long term performance of materials, components and casks will be needed and BAM has already been lauching specific R&D projects addressing identified data gaps. T2 - 8th Annual Nuclear Decommissioning Conference Europe CY - Manchester, UK DA - 24.05.2017 KW - Spent Fuel KW - Storage KW - Disposal PY - 2017 AN - OPUS4-40358 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ringleb, F. A1 - Eylers, K. A1 - Teubner, T. A1 - Schramm, H.-P. A1 - Symietz, Christian A1 - Bonse, Jörn A1 - Andree, Stefan A1 - Heidmann, B. A1 - Schmid, M. A1 - Krüger, Jörg A1 - Boeck, T. T1 - Growth and shape of indium islands on molybdenum at micro-roughened spots created by femtosecond laser pulses N2 - Indium islands on molybdenum coated glass can be grown in ordered arrays by surface structuring using a femtosecond laser. The effect of varying the molybdenum coated glass substrate temperature and the indium deposition rate on island areal density, volume and geometry is investigated and evaluated in a physical vapor deposition (PVD) process. The joined impact of growth conditions and spacing of the femtosecond laser structured spots on the arrangement and morphology of indium islands is demonstrated. The results yield a deeper understanding of the island growth and its precise adjustment to industrial requirements, which is indispensable for a technological application of such structures at a high throughput, for instance as precursors for the preparation of Cu(In,Ga)Se2 micro concentrator solar cells. KW - Indium islands KW - Femtosecond laser patterning KW - Diffusion KW - CIGSe micro solar cells PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S0169433216325764 DO - https://doi.org/10.1016/j.apsusc.2016.11.135 SN - 0169-4332 SN - 1873-5584 VL - 418 SP - 548 EP - 553 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-40551 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hönig, Gerald A1 - Westerkamp, S. A1 - Hoffmann, A. A1 - Callsen, G. T1 - Shielding electrostatic fields in polar semiconductor nanostructures N2 - Polar semiconductor materials enable a variety of classic and quantum-light sources, which are optimized continuously. However, one key problem—the inherent electric crystal polarization of such materials—remains unsolved and deteriorates the radiative exciton decay rate. We suggest a sequence of reverse interfaces to compensate these polarization effects, while the polar, natural crystal growth direction is maintained. Former research approaches, like growth on less-polar crystal planes or even the stabilization of unnatural phases, never reached industrial maturity. In contrast, our concept provides a way for the development of ultrafast devices based on established growth processes for polar materials, while the electric potential landscape becomes adjustable. KW - Piezopolarisation KW - Spontane Polarisation KW - Halbleiterphysik KW - Nanophysik KW - Optoelektronik PY - 2017 DO - https://doi.org/10.1103/PhysRevApplied.7.024004 SN - 2331-7019 VL - 7 IS - 2 SP - 024004-1 EP - 024004-12 PB - American Physical Society CY - College Park, MD 20740-3844 AN - OPUS4-39125 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - A perspective on research on OWEA substructures considering the authorities approval process N2 - Die BAM unterstützt das Bundesamt für Seeschifffahrt und Hydrografie bei der bautechnischen Bewertung von Tragstrukturen für Offshore-Windparks. Im Hinblick auf die vielfältigen nationalen Aktivitäten in Forschung und Entwicklung wird in der eingeladenen Präsentation auf Schwerpunkte behördlicher Erfahrungen und Bedenken Bezug genommen um eine Perspektive auf zukünftigen Forschungsbedarf zu eröffnen. T2 - 7. Gigawind Symposium CY - Leibniz Universität Hannover, Germany DA - 02.03.2017 KW - OWEA KW - Substructures KW - Authorities approval process PY - 2017 AN - OPUS4-39377 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Lazik, D. A1 - Neumann, Patrick P. A1 - Bartholmai, Matthias T1 - Characteristic length measurement of a subsurface gas anomaly - an integrating monitoring approach over heterogeneous distributed gas flow paths N2 - Geogenic gases such as CH4 or CO2 from natural sources, gases (CCS-CO2, H2, Natural gas, City gas …) from a geological repository, or a leaking gas pipeline can present serious risks in industrial and urban areas where the density of infrastructural elements increases as well as above and below ground. To extend the lead time for risk treatment in such critical regions, reliable detection of gases within the shallow subsurface is required to observe critical gas accumulations before degassing into the atmosphere. A near real-time monitoring approach is introduced to determine the volumetric expansion of such a gas escaping from a leak in the subsurface. Considering the pressure relaxation with the ambient air pressure, the approach enables the forecasting of the final size of a pressurized gas body in terms of characteristic lengths. According to theoretical basics, such a characteristic length, which allows to perform a gas (safety) measurement based on a purely geometrical measure, behaves independently of subsurface properties, i.e., it enables a reliable quantification of the escaping gas, irrespective of its heterogeneous flow path distribution. A field test for a 10 l/min pinhole leakage of CO2 injected in an unsaturated Chernozemic soil (agricultural test field Bad Lauchstädt)that was equipped with linear gas sensors demonstrates the lateral-vertical volumetric gas expansion along the environment of these gas sensors, and confirms the applicability of the new characteristic length approach. T2 - UFZ EnergyDays 2017 CY - Leipzig, Germany DA - 15.03.2017 KW - CO2 KW - Carbon capture and storage KW - Leakage KW - Monitoring PY - 2017 AN - OPUS4-39400 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schröder, Volkmar T1 - Sicherheitstechnische Kenngrößen für Biogase N2 - Im Poster wird die Ermittlung sicherheitstechnischer Kenngrößen für Biogase mit Hilfe von Dreistoff-Diagrammen dargestellt. Insbesondere wird die Berechnung der unteren und oberen Explosionsgrenzen (UEG, OEG) und die Ermittlung der Sauerstoffgrenzkonzentration (LOC)beschrieben. T2 - Biogas Infotage 2017 CY - Ulm, Germany DA - 18.01.2017 KW - Biogas KW - Explosionsschutz KW - Explosionsgrenzen KW - Sauerstoffgrenzkonzentration KW - Explosionsdiagramme PY - 2017 AN - OPUS4-39063 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schröder, Volkmar T1 - Explosionsschutz für Biogas-Wasserstoff-Gemische N2 - Bei neueren Verfahren zur Biogasgewinnung wird zusätzlich Wasserstoff in den Fermenter eingespeist, um den Methananteil im Biogas zu erhöhen. Dieses Verfahren bewirkt neben der CO2-Vermeidung eine Erhöhung des Brennwerts und der Qualität des Biogases. Zudem kann dafür, ähnlich wie bei der Einspeisung von Wasserstoff in das Erdgasnetz, Elektrolysewasserstoff aus Überschüssen von Wind- und Solarstrom verwendet werden (Power-to-Gas). Im Poster werden die sicherheitstechnischen Kenngrößen für den Explosionsschutz bei Prozessgasen dargestellt und diskutiert. T2 - Biogas Infotage 2017 CY - Ulm, Germany DA - 18.01.2017 KW - Biogas-Wasserstoff-Gemische KW - Explosionsschutz KW - Sicherheitstechnische Kenngrößen KW - Explosionsgrenzen KW - Explosionsdrücke KW - Normspaltweite PY - 2017 AN - OPUS4-39064 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schröder, Volkmar T1 - Kenngrößen für Gase im Explosionsschutz N2 - Im Poster werden die wichtigsten sicherheitstechnischen Kenngrößen von Gasen für den Explosionsschutz dargestellt. Es wird gezeigt, wie mit Hilfe von Dreistoff-Diagrammen (Explosionsdiagrammen) die Explosionsgrenzen, die Entzündbarkeit und die Sauerstoffgrenzkonzentration von Gemischen aus Brenn- und Inertgasen bestimmt werden. Weiterhin wird eine Zuordnung der Kenngrößen zu den gebräuchlichen Schutzmaßnahmen vorgenommen. T2 - Biogas Infotage 2017 CY - Ulm, Germany DA - 18.01.2017 KW - Explosionsschutz KW - Sicherheitstechnische Kenngrößen KW - Biogas KW - Explosionsgrenzen KW - Explosionsdruck KW - Normspaltweite KW - Explosionsgruppen PY - 2017 AN - OPUS4-39065 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Mehdianpour, Milad T1 - Windbeanspruchung von Hochspannungs-Freileitungsseilen in Naturmessungen, Zeitbereichssimulation und Norm T1 - Wind load of high voltage overhead transmission line con ductors in field measurements, time domain simulations and standard N2 - Die Beanspruchung von Freileitungen erfolgt hauptsächlich durch Naturlasten. Dabei spielt für die bemessungsbestimmenden Lastfälle häufig der Wind eine entscheidende Rolle. Die Leiter, die mehrere hundert Meter weit spannen, tragen einen wesentlichen Anteil zur Gesamtbeanspruchung von Tragmasten bei, die wiederum Eigengewicht und Windlasten der Leiter zwischen zwei Abspannmasten abtragen. Wenn die Reaktion der Seile auf Starkwindereignisse abgeschätzt werden soll, müssen sowohl geometrische Nichtlinearitäten durch die großen Verformungen wie auch aerodynamische Nichtlinearitäten berücksichtigt werden. Insbesondere für die Anwendung und Berücksichtigung in Bemessungsvorschriften werden hierfür Vereinfachungen vorgenommen. In diesem Beitrag wird eine umfassende Untersuchung vorgestellt, über Naturmessungen, FEM-Simulationen kombiniert mit Windkanalversuchen und generierten Windzeitreihen. Ziel ist es, existierende Bemessungsvorschriften im Hinblick auf die Abschätzung der Beanspruchung aus Wind auf Leiter zu validieren. Hierbei sind insbesondere die Turbulenzannahmen und das dynamische Verhalten von weitgespannten Leitern wichtig, um die Extremschnittgrößen zu beschreiben. Mithilfe von so genannten Spannweitenfaktoren sollen die relevanten Parameter, wie Spannweite und Windturbulenz, bei der Beanspruchungsabschätzung berücksichtigt werden. N2 - The loading of overhead lines comprises of natural actions mainly. Wind loading signifies an important load case in the design of overhead transmission line structures. Conductors spanning often several hundreds of meters contribute significantly to the overall loading of suspension towers. Those towers are often designed as a mass product to support the dead and wind load of the conductors between two dead end towers. Estimating the reaction of the conductors to strong winds, both geometric nonlinearities because of the large deformations as well as aerodynamic nonlinearities need to be considered. Particularly for design procedures, those effects should be simplified. This paper presents a thorough investigation comprising field measurements along an existing overhead line, simulations with FEM combined with wind tunnel tests and generated wind fields. It is the aim of the study to validate the actual design procedure regarding loading of wind acting on conductors. Most important herein in order to describe the extreme response are assumptions on turbulence distribution and dynamic behavior of wide spanning overhead line conductors. According to usual design procedure, by means of so called span reduction factors, relevant parameters such as span length and wind turbulence can be considered. KW - Langzeitmessung KW - FEM-Simulation KW - Dynamik PY - 2017 DO - https://doi.org/10.1002/stab. 201710437 SN - 1437-1049 VL - 86 IS - 1 SP - 45 EP - 53 PB - Ernst & Sohn CY - Berlin AN - OPUS4-38899 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Trappe, Volker T1 - Betriebsfestigkeit von imperfekten und reparierten Rotorblättern N2 - Die Betriebsbeanspruchung für Rotorblätter ist aus Messungen bekannt. Schäden an Rotorblättern treten im Betrieb meistens an der Blattschale nach 4-5Jahren, weit vor der projektierten Lebensdauer von 20 Jahren auf und führen zum Anlagenstillstand, wenn sie nicht repariert werden. Mittels eines an der BAM entwickelten FKV-Sandwich-Schalenprüfkörpern kann effizient die Betriebs-festigkeit von Imperfektionen und Reparaturstellen studiert werden. Fertigungsbedingte Imperfektionen (Lagenstöße, Schaumstöße) verkürzen die Lebensdauer ggf. erheblich und führen zu Reparaturen. Experimentell konnte gezeigt werden, dass ein(e) aus-reparierte(r) Schaden/Imperfektion die Betriebsbeanspruchung deutlich besser erträgt, als die schadhafte Struktur.Die numerische Betriebsfestigkeitsvorhersage für FKV ist Gegenstand der Forschung. Gleiches gilt für die Abschätzung der Lebensdauerverkürzung infolge bekannter Fertigungsabweichungen. T2 - OFFSHORETAGE 15.03 - 16.03.2017, CY - Heiligendamm, Germany DA - 15.03.2017, KW - Rotorblätter KW - Windenergie KW - Faser-Kunststoff-Verbunde KW - Betriebsfestigkeit KW - Reparatur PY - 2017 AN - OPUS4-39440 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CHAP A1 - Browne, D. A1 - García-Moreno, F. A1 - Nguyen-Thi, H. A1 - Zimmermann, G. A1 - Kargl, F. A1 - Mathiesen, R. H. A1 - Griesche, Axel A1 - Minster, O. ED - Solanki, K. N. ED - Orlov, D. ED - Singh, A. ED - Neelameggham, N. R. T1 - Overview of In situ X-ray studies of light alloy solidification in microgravity N2 - Gravity has significant effects on alloy solidification, primarily due to thermosolutal convection and solid phase buoyancy. Since 2004, the European Space Agency has been supporting investigation of these effects by promoting in situ X-ray monitoring of the solidification of aluminium alloys on microgravity platforms, on earth, and in periodically varying g conditions. The first microgravity experiment-investigating foaming of liquid metals - was performed on board a sounding rocket, in 2008. In 2012 the first ever X-ray-monitored solidification of a fully dense metallic alloy in space was achieved: the focus was columnar solidification of an Al-Cu alloy. This was followed in 2015 by a similar experiment, investigating equiaxed solidification. Ground reference experiments were completed in all cases. In addition, experiments have been performed on board parabolic flights-where the effects of varying gravity have been studied. We review here the technical and scientific progress to date, and outline future perspectives. KW - Dendritic growth KW - Materials in space KW - Columnar and equiaxed structures PY - 2017 SN - 978-3-319-52392-7 SN - 978-3-319-52391-0 DO - https://doi.org/10.1007/978-3-319-52392-7_80 SN - 2367-1181 SP - 581 EP - 590 PB - Springer CY - Berlin, Heidelberg AN - OPUS4-39442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR T1 - Amts- und Mitteilungsblatt, Band 47, Heft 1 T3 - Amts- und Mitteilungsblatt der BAM - 1/2017 PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-397023 SN - 0340-7551 VL - 47 IS - 1 SP - 1 EP - 358 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-39702 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Martin, S. A1 - Walnsch, A. A1 - Nolze, Gert A1 - Leineweber, A. A1 - Léaux, F. A1 - Scheuerlein, C. T1 - The crystal structure of (Nb0.75Cu0.25)Sn-2 in the Cu-Nb-Sn system N2 - During the processing of superconducting Nb3Sn wire, several intermediate intermetallic phases including a previously encountered Cu-Nb-Sn phase show up. The yet unknown crystal structure of this phase is now identified by a combination of different experimental techniques and database search to be of the hexagonal NiMg2 type with a proposed composition of about (Nb0.75Cu0.25)Sn2. The structure determination started from an evaluation of the lattice parameters from EBSD Kikuchi patterns from quenched material suggesting hexagonal or orthorhombic symmetry. A database search then led to the hexagonal NiMg2 type structure, the presence of which was confirmed by a Rietveld analysis on the basis of high energy synchrotron X-ray powder diffraction data. Assuming a partial substitution of Nb in orthorhombic NbSn2 by Cu, the change of the valence electron concentration provokes a structural transformation from the CuMg2 type for NbSn2 to the NiMg2 type for (Nb0.75Cu0.25)Sn2. In the previous literature the (Nb0.75Cu0.25)Sn2 phase described here has occasionally been referred to as Nausite. KW - Electron backscatter diffraction KW - X-ray diffraction KW - Intermetallic compound KW - Structure solution KW - Superconductor PY - 2017 DO - https://doi.org/10.1016/j.intermet.2016.09.008 SN - 0966-9795 SN - 1879-0216 VL - 80 SP - 16 EP - 21 PB - Elsevier Ltd. AN - OPUS4-37874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Keller, Christian A1 - Herbrich, Uwe T1 - Plastic Instability of Rate-Dependent Materials - A Theoretical Approach in Comparison to FE-Analyses - N2 - The condition for plastic instability is a material characteristic and defines the onset of necking in tensile tests. In large deformation problems of ductile materials it is fundamental to determine the strain at which necking starts as well as the post-necking behaviour in the instability region properly. For verification purposes of material models, usually results of numerical analyses are compared to experimental outcomes. For tensile tests with ductile materials under dynamic loading, it is challenging to obtain comparable experimental and numerical results in terms of the onset of necking and the post-critical deformation behaviour. This paper focuses on the derivation of a theoretical criterion describing the plastic instability in rate-dependent materials based on the time variation of the strain gradient in a tensile specimen under isothermal conditions. We examine the influence of various constitutive equations on the theoretical stability condition predicted by different multiplicative as well as additive approaches. For multiplicative relations, the results indicate that the onset of necking is, in principle, independent of the strain rate, whereas for the considered additive relation, the dynamic necking strain must decrease with increasing strain rate. In conclusion, the theoretical stability condition is related to results from finite element simulations of dynamic tensile tests with various loading rates. It is shown that the simulated and the theoretical predicted onset of plastic instability agree reasonably. T2 - 11th European LS-DYNA Conference CY - Salzburg, Austria DA - 09.05.2017 KW - FEM KW - Plastic Instability KW - Dynamic Tensile Test PY - 2017 UR - http://www.dynalook.com/11th-european-ls-dyna-conference/crash-metal-failure/plastic-instability-of-rate-dependent-materials-a-theoretical-approach-in-comparison-to-fe-analyses SP - 1 EP - 10 AN - OPUS4-40660 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Keller, Christian T1 - Plastic Instability of Rate-Dependent Materials - A Theoretical Approach in Comparison to FE-Analyses - N2 - The condition for plastic instability is a material characteristic and defines the onset of necking in tensile tests. In large deformation problems of ductile materials it is fundamental to determine the strain at which necking starts as well as the post-necking behaviour in the instability region properly. For verification purposes of material models, usually results of numerical analyses are compared to experimental outcomes. For tensile tests with ductile materials under dynamic loading, it is challenging to obtain comparable experimental and numerical results in terms of the onset of necking and the post-critical deformation behaviour. This paper focuses on the derivation of a theoretical criterion describing the plastic instability in rate-dependent materials based on the time variation of the strain gradient in a tensile specimen under isothermal conditions. We examine the influence of various constitutive equations on the theoretical stability condition predicted by different multiplicative as well as additive approaches. For multiplicative relations, the results indicate that the onset of necking is, in principle, independent of the strain rate, whereas for the considered additive relation, the dynamic necking strain must decrease with increasing strain rate. In conclusion, the theoretical stability condition is related to results from finite element simulations of dynamic tensile tests with various loading rates. It is shown that the simulated and the theoretical predicted onset of plastic instability agree reasonably. T2 - 11th European LS-DYNA Conference CY - Salzburg, Austria DA - 09.05.2017 KW - FEM KW - Plastic Instability KW - Dynamic Tensile Test PY - 2017 AN - OPUS4-40662 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, René T1 - Akustische Überwachung von Transformatoren mit Glasfasern?! N2 - Vorstellung aktueller Ergebnisse der Quasi-verteilten faseroptische Sensorik für die Echtzeit-Diagnostik von Hochspannungstransformatoren. T2 - Seminar Hochspannungstechnik und Energieversorgung CY - Technische Universität Berlin, Germany DA - 30.05.2017 KW - C-OTDR KW - Distributed acoustic sensing KW - Quasi-distributed vibration sensing KW - Structural health monitoring PY - 2017 AN - OPUS4-40637 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, René T1 - Advanced distributed acoustic monitoring N2 - New progress of developments of distributed acoustic monitoring. Review of previous results and lastest improvements. T2 - Seminar Angewandte Photonik CY - Goslar, Germany DA - 15.06.2017 KW - Distributed acoustic sensing KW - Structural health monitoring KW - Quasi-distributed sensing KW - Fibre optic sensors PY - 2017 AN - OPUS4-40640 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kühnel, C. A1 - Bardl, Richard A1 - Stengel, Dominik A1 - Kiewitt, W. A1 - Grossmann, S. T1 - Investigations on the mechanical and electrical behaviour of HTLS conductors by accelerated ageing tests N2 - To cope with future requirements, the transfer capacities of distribution systems as well as of transmission systems in Europe need to be increased. Therefore repowering of existing overhead lines with high temperature low sag con-ductors (HTLS) can be one interesting possibility. Because of limited experiences with that technology, current re-search of TU Dresden, the Federal Institute for Materials Research and Testing (BAM) and 50Hertz Transmission GmbH investigates the ageing behaviour of several differ-ent HTLS technologies in a consortium with other Euro-pean partners. In this context, accelerated ageing tests of conductors and its corresponding fittings with combined mechanical and electrical loads are done. To evaluate the changes due to ageing, several mechanical tests of the con-ductors are carried out and the contact behaviour of the fittings is analysed. T2 - CIRED Conference CY - Glasgow, Scotland, UK DA - 12.06.2017 KW - HTLS KW - High temperature low sag KW - Resistance KW - Self-damping PY - 2017 SP - Paper 0200, 1 EP - 5 AN - OPUS4-40869 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palkowski, Carsten T1 - Technical and economical evaluation of energy efficiency testing for heat pumps N2 - In order to increase the total amount of energy savings to be reached in 2020 and 2050 the German government launched a number of initiatives. One of the associated projects aims to support market surveillance authorities in the field of Ecodesign and Energy Labelling, thereby increasing confidence in these instruments. The surveillance of heating appliances is of great importance as the energy consumed by space heaters accounts for a significant share of the total energy demand in the European Union. In this study heat pumps are analyzed as a high efficiency technology and prospective candidate for large energy savings. It is focused on both validating the current measurement standards for heat pumps and further developing these methods for the benefit of market surveillance authorities. The test method standards, EN 14511 and EN 14825, for testing heat pumps regarding their performance and energy efficiency are validated by conducting round robin tests in independent and accredited test laboratories. Based on these tests the reproducibility and repeatability of the standardized test methods and the laboratories in Europe are assessed. Identifying deficiencies in the methods is a fundamental step towards a sustained improvement process. Optimization proposals will be developed based on these fundamental investigations and brought to the attention of standardization bodies. It was figured out that the currently used test methods exhibit high complexity, high financial effort and reveal significant deviations of testing results depending on whether they were determined under laboratory or field test conditions. New testing and calculation methodologies are developed to simplify the process with the aim to increase the accuracy and affordability of the energy efficiency testing of heat pumps. T2 - 9th Asia-Pacific Power and Energy Engineering Conference (APPEEC 2017) CY - Chengdu, China DA - 15.04.17 KW - Heat pump KW - Energy efficiency KW - Test method standard optimization KW - Energy labelling KW - Climate change PY - 2017 AN - OPUS4-40800 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palkowski, Carsten T1 - EU Energy Label for heating appliances - Optimization of test standards for heat pumps N2 - The European Standards EN14511 and EN14825 are representing standardized procedures for testing the energy efficiency of heat pumps and air conditioners with electrically driven compressors for both space heating and cooling. In this study, these standards are analyzed and validated. It was figured out that the currently used methods implicate high complexity and high financial effort. In order to clarify the circumstances and to identify the deficits more in detail, a round robin test with independent and accredited laboratories was initiated. The aim is to develop an optimized test procedure that improves the feasibility of the testing procedure and finally its application. This study should lead to a repeatable and reproducible testing procedure, which is also compatible with the state of the art in heat pump technology and real operation conditions. T2 - ECEEE Summer Study 2017 CY - Hyerès, France DA - 29.05.2017 KW - Heat pump KW - Energy efficiency KW - Test method standard optimization KW - Energy labelling KW - Climate change PY - 2017 AN - OPUS4-40801 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR T1 - Amts- und Mitteilungsblatt, Band 47, Heft 2 T3 - Amts- und Mitteilungsblatt der BAM - 2/2017 PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-408040 SN - 0340-7551 VL - 47 IS - 2 SP - 359 EP - 453 PB - Bundesanstalt für Materialforschung und -prüfung (BAM) CY - Berlin AN - OPUS4-40804 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bauer, Ute A1 - Behrens, H. A1 - Reinsch, Stefan A1 - Morin, E. I. A1 - Stebbins, J. F. T1 - Structural investigation of hydrous sodium borosilicate glasses N2 - The structural properties of a borosilicate glass with nominal 16 mol% Na2O, 10 mol% B2O3 and 74mol% SiO2 and water contents between 0 and 8wt% H2O (0–22 mol% H2O)were investigated with IR, Raman and 11BMAS NMR spectroscopy. In addition to the pronounced OH stretching vibration band of weakly H-bonded species at 3580 cm−1 the MIR spectra show a triplet at 2900, 2350 and 1750 cm−1, similar as observed in water-bearing silicate glasses. These bands are assigned to OH groups and water molecules which are strongly H-bonded, to non-bridging oxygen. Water species contents determined from absorption bands in the NIR at 5200 cm−1 (molecular H2O), 4700 cm−1 (B\\OH), and 4500 cm−1 (Si\\OH) indicate that hydroxyl groups dominate up to ~6 wt% total H2O. Based on the absorption coefficients known from literature for silicate and borate glasses the B\\OH/Si\\OH ratio is estimated to be ≈0.8. As indicated by density, Raman and NMR data the incorporation ofwater has strong structural impacts in particular at low water contents up to 3 wt% H2O. While the nominally dry glasses still contain a significant fraction (12%) of three-fold coordinated boron, almost all boron is four-fold coordinated in hydrous glasses. The increase of band components in the Raman spectra near 900 cm−1 relative to the region N 1050 cm−1 gives evidence for depolymerization of the network upon hydration. Fitting of the spectra with Gaussians implies that silica tetrahedra with two non-bridging oxygen (Q2) are preferentially formed by reactionwithwater on expense of tetrahedra linked to four tetrahedra (Q4). KW - Glass structure KW - Borosilicate glasses KW - Water-bearing glasses KW - Spectroscopy PY - 2017 DO - https://doi.org/10.1016/j.jnoncrysol.2017.03.023 SN - 0022-3093 SN - 1873-4812 VL - 465 SP - 39 EP - 48 PB - Elsevier B. V. AN - OPUS4-40805 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Barnefske, Lena T1 - Entwicklung eines mechanisch verstärken und selbstheilenden Silikonelastomers auf Basis eines Kapsel-basierten Ansatzes N2 - Im Arbeitskreis von Herrn Prof. Dr. Menzel (TU Braunschweig) wurde in Sievershausen ein Vortrag zum Thema „Self-healing and mechanically reinforced silicone rubber by the use of multifuctional capsules“ gehalten. Der Vortrag beginnt mit einer kurzen Motivation und einem Überblick über selbstheilende Materialien. Daraufhin werden die Ergebnisse zur Entwicklung eines selbstheilenden Silikonelastomers auf Basis von Kapseln, bestehend aus einem PDMS Kern und einer POS Hülle, dargestellt. Es folgt die Analytik, die auf DLS, TGA, UV/Vis und Fluoreszenzspektroskopie sowie SEM beruht. Der Vortrag endet mit einem Ausblick über zukünftige Arbeiten auf dem Gebiet. T2 - Seminar in Sievershausen CY - Sievershausen, Lehrte, Germany DA - 07.06.2017 KW - Selbstheilung KW - PDMS PY - 2017 AN - OPUS4-40857 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüllmann, Dino T1 - Aerial Robot Olfaction - Mobile Gas Sensors N2 - An introduction to BAM, gas source localisation and gas distribution mapping is given. Both an example for in-situ and open-path gas sensors is shown. The flight platforms used at BAM are introduced. T2 - Workshop "Drohnen in der Wissenschaft" CY - Potsdam, Germany DA - 30.06.2017 KW - Gassensor KW - Olfaction KW - Multicopter PY - 2017 AN - OPUS4-40858 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Krankenhagen, Rainer T1 - Detektion von Fertigungsschäden mithilfe thermografischer Tiefenprüfung N2 - Thermografie als zerstörungsfreies Prüfverfahren ist prinzipiell gut geeignet, um innen liegende Fehler in Rotorblättern zu detektieren. Im Vortrag wird die Anwendbarkeit des Messprinzips zuerst theoretisch und dann an Hand von Praxisfällen gezeigt. Weiterhin werden erste Ergebnisse aus einem laufenden FuE-Projekt zur Tiefenreichweite der Messmethode demonstriert und erläutert. T2 - 6. VDI-Fachkonferenz "Rotorblätter von Windenergieanlagen" CY - Bremen, Germany DA - 27.06.2017 KW - Thermografie KW - Fertigungsfehler KW - Rotorblatt PY - 2017 AN - OPUS4-40861 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kuschke, Christian A1 - Wille, Frank A1 - Ballheimer, Viktor A1 - Sterhaus, Jens A1 - Apel, Andreas T1 - Standards and guidelines for design of trunnions of RAM transport packages N2 - Trunnion systems of packages for the transport of radioactive materials have to guarantee the safe handling of package during crane operations (lifting, tilting) and to secure package tie down to the transport vehicle, if the trunnions are used as attachment points during transport. The design of trunnions is based on IAEA Regulations SSR-6, the supporting Advisory Material SSG-26 and further appropriate technical standards and/or guidelines. For package approval procedures in Germany the guideline BAM-GGR 012 has to be applied. If a package is handled inside a german nuclear power plant, the standard KTA 3905 has to be fulfilled additionally. In this paper the requirements of KTA 3905 concerning the trunnion systems as load attaching points (LAP) are discussed in connection with the recommendations in the guideline BAM-GGR 012. This guideline is prepared at BAM Federal Institute for Materials Research and Testing for analysis and assessment of bolted lid and trunnion systems of Type B(U) transport packages. The Quality assurance questions concerning trunnion systems are discussed as well. T2 - WM 2017 conference CY - Phoenix, USA DA - 05.03.2017 KW - RAM transport package KW - Trunnions PY - 2017 SP - Paper 17365, 1 EP - 12 AN - OPUS4-40815 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, René T1 - Applications of distributed acoustic sensing N2 - Review of early AIP related early developments. Overview of distributed methods at BAM. Examples of applications of distributed acoustic sensing for infrastructure monitoring. T2 - innoFPSEC Photonik Seminar CY - Potsdam, Germany DA - 07.06.2017 KW - Fibre-optic sensing KW - Distributed acoustic sensing KW - Structural health monitoring PY - 2017 AN - OPUS4-40641 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Eisermann, René T1 - Reducing sensitivity fading in C-OTDR by use of enhanced scattering fiber segments N2 - We have shown that for C-ODTR based DAS two UV-inscribed scattering segments within an optical fiber have a significant influence on the local sensitivity Fading characteristics. This method was experimental proven to be suitable for distributed dynamic strain measurement in a thermally unstable environment. Signal-to-noise ratio analyses for detecting a signal peak within the time-dependent spectra were performed. Results show an increase in SNR and additionally that the occurrence of total loss of sensitivity (SNR <1) could be decreased by a factor of six when compared to an untreated standard fiber. T2 - 25th International Conference on Optical Fiber Sensors CY - Jeju-City, Jeju, Republic of Korea DA - 24.04.2017 KW - Coherent Rayleigh OTDR KW - Distributed acoustic sensing KW - Distributed vibration sensing KW - Fiber sensors KW - Quasi-distributed sensing KW - Rayleigh scattering PY - 2017 AN - OPUS4-40643 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kapa, Thomas T1 - Distributed Brillouin Sensors N2 - This presentation starts with an overview of various optical sensing applications of Department 8.6 Fiber Optic Sensors. Main topic of presentation is distributed Brillouin sensing of strain and temperature by Brillouin Optical Frequency Domain Analysis (BOFDA). For power grids of offshore wind farms temperature and strain sensing should prevent or rapidly reveal costly break downs. T2 - Seminarvortrag TU Clausthal CY - Goslar, Germany DA - 15.06.2017 KW - Fibre Optic Sensors KW - Stimulated Brillouin Scattering KW - Distributed Sensing PY - 2017 AN - OPUS4-40966 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Geißler, Peter T1 - Verdichtungsinjektionen - numerische und experimentelle Betrachtungen N2 - Die Verdichtungsinjektion stellt ein Verfahren in der Geotechnik dar, bei dem der Baugrund durch Einpressen eines Mörtels mit hoher innerer Reibung verdichtet wird, ohne ihn aufzubrechen. Dieses Verfahren wird weithin verwendet zur Setzungskontrolle oder Erhöhung der Tragfähigkeit des Baugrunds unter neuen bzw. bestehenden Bauwerken. Da die Injektion innerhalb des Bodens stattfindet, ist eine visuelle Beurteilung des Verdichtungserfolgs nicht möglich. Bisher beruht die Beurteilung bzw. Bewertung daher zumeist auf Erfahrungen. Ziel ist es somit mittels numerischer und experimenteller Untersuchungen eine Methode zu erschaffen, die es ermöglicht den Verdichtungserfolg nicht nur vorherzusagen sondern auch bezüglich der Materialparameter des Injektionsguts zu optimieren. Bezüglich der Numerik werden sowohl die grundsätzliche Eignung als auch die ersten notwendigen Anpassungen der impliziten "Material Point Method" zur Simulation einer Verdichtungsinjektion präsentiert. Für die experimentellen Untersuchungen wurde eigens ein Versuchsstand konstruiert, in dem es möglich ist, den Injektionsprozess an einer Glasscheibe zu beobachten und mittels digitaler Bildverarbeitung zu bewerten. T2 - Workshop "Große Verformungen" CY - Berlin, Germany DA - 13.06.2017 KW - Verdichtungsinjektionen KW - Material point method KW - Nichtlinearitäten KW - Updated Lagrange Formulierung KW - u-p-Formulierung KW - Digitale Bildverarbeitung KW - Particle image velocimetry KW - Close range photogrammetry PY - 2017 AN - OPUS4-40894 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - INPR A1 - Schlichting, S. A1 - Hönig, Gerald A1 - Müßener, J. A1 - Hille, P. A1 - Grieb, T. A1 - Teubert, J. A1 - Schörmann, J. A1 - Wagner, M. R. A1 - Rosenauer, A. A1 - Eickhoff, M. A1 - Hoffmann, A. A1 - Callsen, G. T1 - Tuning of the Quantum-Confined Stark Effect in wurtzite [000-1] group-III-nitride nanostructures by the Internal-Field-Guarded-Active-Region Design N2 - Recently, we suggested an unconventional approach [the so-called Internal-Field-Guarded-Active-Region Design (IFGARD)] for the elimination of the crystal polarization field induced quantum confined Stark effect (QCSE) in polar semiconductor heterostructures. And in this work, we demonstrate by means of micro-photoluminescence techniques the successful tuning as well as the elimination of the QCSE in strongly polar [000-1] wurtzite GaN/AlN nanodiscs while reducing the exciton life times by more than two orders of magnitude. The IFGARD based elimination of the QCSE is independent of any specific crystal growth procedures. Furthermore, the cone-shaped geometry of the utilized nanowires (which embeds the investigated IFGARD nanodiscs) facilitates the experimental differentiation between quantum confinement- and QCSE-induced emission energy shifts. Due to the IFGARD, both effects become independently adaptable. KW - Piezoelectricity KW - Quantum Confined Stark Effect (QCSE) KW - Nanophotonics KW - Semiconductor nanostructures KW - Spontaneous polarization KW - Internal-Field-Guarded-Active-Region Design (IFGARD) PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-411013 DO - https://doi.org/10.48550/arXiv.1707.06882 SN - 2331-8422 SP - 1 EP - 9 PB - Cornell University CY - Ithaca, NY AN - OPUS4-41101 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stengel, Dominik A1 - Thiele, K. A1 - Clobes, M. A1 - Mehdianpour, Milad T1 - Aerodynamic damping of nonlinear movement of conductor cables in wind tunnel tests, numerical simulations and full scale measurements N2 - Aerodynamic damping is a decisive parameter influencing the dynamic response of overhead transmission line conductors. Methods of how to account for the effects of aerodynamic damping differ significantly and so might do the results. In this work, the source of aerodynamic damping being the result of the relative velocity between the structure and wind flow will be revised. Based on wind tunnel tests and validated by simulations, the differences of linear movement compared to a pendulum movement of a sagging cable are shown. The reasons for that Deviation are the large deflections, resulting in a movement non-parallel to the acting wind flow. For analysis in frequency domain, it is not possible to incorporate aerodynamic damping implicitly by fluid structure interaction. If the dynamic movement can be linearized at a working point of the mean deflection, a modification to the linear approach is suggested. This approach is validated by simulation with a finite element model of an existing overhead transmission line, calibrated with full scale measurements. Aerodynamic damping is incorporated in time step analysis by Rayleigh damping and modal damping. The differences between both approaches are emphasized and modal damping is shown to be the most adequate. KW - Aerodynamic damping KW - Overhead transmission lines KW - Conductors KW - Nonlinearities PY - 2017 DO - https://doi.org/10.1016/j.jweia.2017.07.002 SN - 0167-6105 SN - 1872-8197 VL - 169 SP - 47 EP - 53 PB - Elsevier AN - OPUS4-41028 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schönhals, Andreas T1 - Molecular dynamics of discotic liquid crystals in the bulk and embedded in nanochanels N2 - Discotic liquid crystals (DLCs) are self-assembled materials where self-assembly is driven by non-covalent intermolecular interactions. The corresponding molecules consist of a flat and rigid aromatic core substituted by flexible aliphatic side chains. While the former is responsible for the π-stacking, the latter gives rise to an increased solubility, processability, and rich thermotropic behavior. The disc-shaped molecules form columns that further assemble into two-dimensional arrays with a hexagonal mesophase. The alkyl chains fill the intracolumnar space giving rise to a nanophase separated state. These soft matter materials with highly ordered columnar structures have a great potential in molecular electronic devices such as active semiconductors in organic field-effect transistors and photovoltaic devices with a charge carrier mobility of up to 1.1 cm2/Vs. Two different homologous systems based on triphenylene derivatives were investigated as model systems for DLCs where the length of the aliphatic side chains is widely varied. Structural information is retrieved by X-ray diffraction carried out on a synchrotron. Experiments were carried out in the bulk state and confined to the nanometer wide channels of anodic aluminum membranes (Pore diameter 20 nm, 40nm, 80 nm and 180 nm). The latter case can be considered as a promising way to prepare nanowires. As method broadband dielectric spectroscopy (frequency range 10-2 Hz to 109 Hz) is employed. These experiments were accompanied by thermal investigations (Differential Scanning Calorimetry as well as Thermogravimetric Analysis) as well as inelastic neutron scattering (neutron Time-of-Flight and neutron Backscattering). The dynamics of these unique soft matter materials are discussed in detail considering their structure (length of the aliphatic side chain), the effect of self-confinement (of the aliphatic chains in the intracolumnar space) and of the outer confinement (influence of the pore size). Comparison is further made to a pyrene based system. T2 - THE 9th INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS, ROCAM 2017 CY - Bucharest, Romania DA - 11.07.2017 KW - Dicotic liquid crystals PY - 2017 AN - OPUS4-41023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dutto, Paola T1 - Suction buckets behaviour under tensile loads: A numerical study with FEM N2 - Suction Bucket Jackets (SBJ) are found as a suitable alternative to driven piles for the support of foundations for offshore wind energy converters. In the case of jackets or multipods, a predominant vertical load is to be expected. The effect of such a tensile loading is the generation of suction in the soil inside the bucket which leads to an increment of tensile capacity. This paper aims to study the bearing behaviour of a suction foundation by taking into account how the soil permeability and the loading rate influence the foundation behaviour. Moreover, after submitting the structure to a storm load, the bearing capacity is studied again, in order to see the effect of such a load on the bucket's bearing behaviour. This study is carried out by means of Finite Element numerical simulations based on the formulation of Biot's equations combined with a constitutive model that reproduces the key aspects of cyclic soil behaviour in the frame of Generalized Plasticity. T2 - International Ocean and Polar Engineering Conference CY - San Francisco, USA DA - 25/06/2017 KW - Finite element method KW - Offshore wind energy converter KW - Suction bucket KW - Generalized plasticity KW - Sand KW - Numerical simulation KW - Tensile capacity PY - 2017 AN - OPUS4-41054 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hüllmann, Dino A1 - Kohlhoff, Harald A1 - Erdmann, Jessica A1 - Neumann, Patrick P. ED - Emri, Igor T1 - Current-independent torque control of permanent-magnet synchronous motors N2 - A current-independent torque equation for the permanent-magnet synchronous motor (PMSM) aiming at direct-drive servo applications is derived from a first principles model. Instead of measuring currents, all required control parameters are derived from optical incremental encoder measurements. The results are verified on a real system in test series showing the effect of static friction and proving the obtained torque model. T2 - 33rd Danubia Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - BLDC KW - Motor control KW - PMSM KW - Servo drive PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S2214785317308271 DO - https://doi.org/10.1016/j.matpr.2017.06.052 SN - 2214-7853 VL - 4 IS - 5 SP - 5821 EP - 5826 PB - Elsevier CY - Amsterdam, Netherlands AN - OPUS4-41580 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neumann, Patrick P. A1 - Lazik, D. A1 - Bartholmai, Matthias ED - Emri, Igor T1 - Validation of membrane-based linear soil gas sensors under field conditions N2 - A 400 m2 soil test field with gas injection system was built up, which enables an experimental validation of linear membrane-based gas sensors – a sensor technology which was developed based on the selective permeation of gases through membranes. Several soil watering and injection experiments with carbon dioxide at different days with varying boundary conditions were performed showing that the sensor behaves mostly insensitive to the environmental conditions investigated, i.e., barometric pressure fluctuations, soil temperature, air temperature and humidity, sun duration, and wind speed. Furthermore, depending on water infiltration, a gas phase displacement could be observed in-situ based on the changed measurement signal. The results of the validation experiments highlight the potential of the method for rapid leak detection and localization qualifying the sensor particularly for safety applications, e.g., in underground gas storage areas. T2 - 33nd Danubia Adria Symposium on Advances in Experimental Mechanics CY - Portorož, Slovenia DA - 20.09.2016 KW - Distributed linear sensor KW - Membrane-based gas sensing KW - Subsurface monitoring KW - Gas storage areas KW - Validation PY - 2017 UR - http://www.sciencedirect.com/science/article/pii/S2214785317308404 DO - https://doi.org/10.1016/j.matpr.2017.06.065 SN - 2214-7853 VL - 4 IS - 5, Part 1 SP - 5893 EP - 5897 PB - Elsevier Ltd. AN - OPUS4-41584 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin A1 - Eisenacher, Germar A1 - Schönfelder, Thorsten A1 - Wille, Frank T1 - Development of a material model for the crush of spruce wood N2 - Typical transport packages used in Germany are equipped with wooden impact limiting devices. In this paper we give an overview of the latest status regarding the development of a finite element material model for the crush of spruce wood. Although the crush of wood – mainly in longitudinal direction – is a phenomenon governed by macroscopic fracture and failure of wood fibres we smear fracture and failure mechanisms over the continuous voume. In first step we altered an existing LS-DYNA material model for foams, which considers an ellipse shaped yield surface written in terms of the first two stress invariants. The evolution of the yield surface in the existing model depends on the volumetric strain only. For the use with spruce wood, we modified the existing material model to consider the deviatoric strain for the evolution of the yield surface as well. This is in accordance with the results of crush tests with spruce wood specimens, where the crushing deformation was rather deviatoric for uniaxial stress states and rather volumetric for multiaxial stress states We rate the basic idea of this approach to be reasonable, though other problems exist regarding the shape of the yield surface and the assumption of isotropic material properties. Therefore we developed a new transversal isotropic material model with two main directions, which considers different yield curves according to the multiaxiality of the stress state via a multi-surface yield criterion and a non-associated flow rule. The results show the ability to reproduce the basic strength characteristics of spruce wood. Nevertheless, problems with regularization etc. show that additional investigations are necessary. T2 - ASME PVP 2017 CY - Waikaloa, HY, USA DA - 16.07.2017 KW - Chrush KW - Spruce KW - Wood KW - FEM PY - 2017 SN - 978-0-7918-5802-8 VL - 7 SP - Article UNSP V007T07A037, 1 EP - 9 AN - OPUS4-41613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Neumann, Martin T1 - Development of a material model for the crush of spruce wood N2 - Typical transport packages used in Germany are equipped with wooden impact limiting devices. In this paper we give an overview of the latest status regarding the development of a finite element material model for the crush of spruce wood. Although the crush of wood – mainly in longitudinal direction – is a phenomenon governed by macroscopic fracture and failure of wood fibres we smear fracture and failure mechanisms over the continuous voume. In first step we altered an existing LS-DYNA material model for foams, which considers an ellipse shaped yield surface written in terms of the first two stress invariants. The evolution of the yield surface in the existing model depends on the volumetric strain only. For the use with spruce wood, we modified the existing material model to consider the deviatoric strain for the evolution of the yield surface as well. This is in accordance with the results of crush tests with spruce wood specimens, where the crushing deformation was rather deviatoric for uniaxial stress states and rather volumetric for multiaxial stress states We rate the basic idea of this approach to be reasonable, though other problems exist regarding the shape of the yield surface and the assumption of isotropic material properties. Therefore we developed a new transversal isotropic material model with two main directions, which considers different yield curves according to the multiaxiality of the stress state via a multi-surface yield criterion and a non-associated flow rule. The results show the ability to reproduce the basic strength characteristics of spruce wood. Nevertheless, problems with regularization etc. show that additional investigations are necessary. T2 - ASME PVP 2017 CY - Waikaloa, HY, USA DA - 16.07.2017 KW - Crush KW - Wood KW - Spruce KW - FEM PY - 2017 AN - OPUS4-41617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Le, Quynh Hoa A1 - Bäßler, Ralph A1 - Yevtushenko, Oleksandra A1 - Kratzig, Andreas A1 - Bettge, Dirk T1 - Synergistic effects of impurities in the condensate on the corrosion of CO2 transport pipeline N2 - For the reliability of transport pipelines the corrosion resistance of the materials used needs to be determined in conditions, which are possible during the transport process. In some situations condensation of components out of the CO2 stream can occur. To study the effect of condensate on transport pipeline steel, a “worst-case scenario” gas mixture, containing 2.5 % H2O, 1.8 % O2, 1000 ppmv NO2, and 220 ppmv SO2, was proposed, fed (1.5 L/min) into a glass reactor containing coupon-shaped specimens for 120 600 h at 278 K (to simulate the underground pipeline transport), and resulted in the condensate containing 0.114 M H2SO4 and 0.0184 M HNO3 (pH 2.13). Basing on this “original” condensate, exposure tests and electrochemical characterization together with pH and conductivity in CO2 saturated condition at the same temperature were carried out. The role of each gas impurity and the combination of them, when the condensate is formed, was studied by investigating the role of individual and varying combination of acidic components in the condensate on the corrosion behaviors of the commercial pipeline-steel (L360NB). It can be concluded that although the condensation of NOx in form of HNO3 causes faster corrosion rate, it is the condensation of SOx or the combination of SOx and NOx that may cause much more severe problems in form of localized and pitting corrosions. Different to the corrosion products formed in CO2 atmosphere without impurities (mainly iron carbonate) the corrosion products resulted from these acidic condensation have no protectability, indicating the need of controlling gas quality during the transportation within the pipeline network. T2 - EUROCORR 2017 - PRAG CY - Prague, Czech Republic DA - 03.09.2017 KW - CCUS KW - CO2 corrosion KW - Carbon steels KW - Condensate PY - 2017 SP - Paper 75636,.1 EP - 4 AN - OPUS4-41874 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schneider, Ronald T1 - Konzept zur Einbindung der Strukturüberwachung in die risikobasierte Inspektionsplanung von Offshore-Strukturen N2 - Das Ermüdungsverhalten einzelner Schweißverbindungen in Offshore-Strukturen ist stark korreliert. Diese Korrelation entsteht zum einen durch die Verwendung gleicher Prozesse und Materialien bei der Herstellung der Verbindungen, zum anderen sind die ermüdungswirksamen Lasten an verschiedene Hospots im Tragwerk ebenfalls von einander abhängig. Hieraus ergeben sich Systemeffekte, die es ermöglichen, durch stichprobenartige Inspektion des Zustandes einzelner Hotspots auf den Zustand der verbleibenden Hotspots im Tragwerk zu schließen. Auf dieser Grundlage können Inspektions- und Reparaturstrategien für ermüdungsbeanspruchte Offshore-Strukturen mit Hilfe von riskobasierten Methoden optimiert werden. In diesem Vortrag wird weiterführend ein Konzept zur Einbindung von globalen Monitoringergebnissen in die risikobasierte Inspektionsplanung vorgestellt. T2 - 29. Sitzung des VDI/VDE-GMA Fachausschuss 2.12 Strukturanalyse und -überwachung in der Bautechnik im Fachbereich Prozessmesstechnik und Strukturanalyse CY - Bremen, Germany DA - 06.09.2017 KW - Ermüdung KW - Offshore-Strukturen KW - Risikobasierte Inspektionsplanung KW - Monitoring PY - 2017 AN - OPUS4-41865 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schlegel, Moritz-Caspar T1 - Nano-porous Materials - Introduction into Metal-organic Frameworks N2 - Metallic organic frameworks are the materials stirring great interest by their large variety of structure types and chemical composition as well as low density and very high surface area, which are desirable properties for gas storage such as for hydrogen, methane or carbon dioxide. Using different so called secondary building units offer an opportunity to form tunable structures with channels of various geometry and allow in this way to study the absorption of the molecular hydrogen, methane or carbon dioxid in the systematic way. T2 - Neutron Scattering Application to Hydrogen Storage Materials CY - Berlin, Germany DA - 07.08.2017 KW - MOFs KW - Hydrogen KW - Crystallography PY - 2017 AN - OPUS4-41285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Palkowski, Carsten A1 - Schlegel, Moritz-Caspar A1 - Akkerman, Floris A1 - Simo, Anne T1 - EU Energy Label for heating appliances - Optimization of test standards for heat pumps N2 - The European Standards EN14511 and EN14825 are representing standardized procedures for testing the energy efficiency of heat pumps and air conditioners with electrically driven compressors for both space heating and cooling. In this study, these standards are analyzed and validated. It was figured out that the currently used methods implicate high complexity and high financial effort. In order to clarify the circumstances and to identify the deficits more in detail, a round robin test with independent and accredited laboratories was initiated. The aim is to develop an optimized test procedure that improves the feasibility of the testing procedure and finally its application. This study should lead to a repeatable and reproducible testing procedure, which is also compatible with the state of the art in heat pump technology and real operation conditions. T2 - ECEEE Summer Study 2017 CY - Hyères, France DA - 29.05.2017 KW - Climate change KW - Energy efficiency KW - Energy labelling KW - Heat pumps KW - Test method standard optimization PY - 2017 SN - 978-91-983878-1-0 SN - 2001-7960 SP - 1551 EP - 1555 AN - OPUS4-41287 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Akkerman, Floris T1 - Die Ökodeisgn-Richtlinie N2 - Allgemeiner Vortrag zur Ökodesign-Richtlinie und ihrer Bedeutung für die Industrie. T2 - Großes Netzwerktreffen Süd CY - IHK Ulm, Germany DA - 30.05.2017 KW - Ökodeisgn KW - Energieeffizienz KW - EU-Recht PY - 2017 AN - OPUS4-41255 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Knieschewski, Arno T1 - How standards can better reflect consumer relevance on the example of range Hoods N2 - The performance test of range hoods can be improved by using an atomizer nozzle. T2 - ECEEE 2017 summer study on energy efficiency CY - Hyères, France DA - 29.05.2017 KW - Range hood KW - Energy efficiency PY - 2017 AN - OPUS4-41139 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Knieschewski, Arno T1 - How standards can better reflect consumer relevance on the example of range hoods N2 - The EU’s Ecodesign and Energy Labelling Regulations for domestic cooking appliances became legally binding in 2015. To determine the classes on the energy label, the regulations refer to the European Standard for performance measurements of range hoods EN 61591. The standard EN 61591 has been analysed and evaluated within the National Action Plan on Energy Efficiency (NAPE), a government programme that aims to increase the energy efficiency in Germany. The analysis revealed several drawbacks of the test standard. The standard used for the evaluation of range hoods is composed of methods for determining: (i) volumetric airflow, (ii) odour extraction, (iii) effectiveness of the lighting system and (iv) grease absorption. Currently, the grease absorption class is obtained by heating up oil and water in a pot, which creates vapour and splashes of grease. In this paper different alternative methods for the evaluation of the grease absorption efficiency will be discussed. In the proposed test method an atomizer nozzle is used. Consequently, the exact amount of atomized oil is known and the ratio of filtered to atomized oil can be measured. Thereby the proposed new method is able to take into account aerodynamic designs and leaks. Furthermore, it enables to alter the classification guideline of the energy label to give more significant and consumer relevant declarations. It allows manufacturers to develop innovative grease absorption methods with little airflow. This study revealed that it can be beneficial to review more of the existing standards in the light of improving their consumer relevance. T2 - ECEEE 2017 - Summer Study on energy efficiency CY - Hyères, France DA - 29.05.2017 KW - Range hood KW - Energy efficiency KW - Energy label PY - 2017 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-411425 SN - 978-91-983878-0-3 SN - 978-91-983878-1-0 SN - 2001-7960 SN - 1653-7025 SP - 1557 EP - 1561 AN - OPUS4-41142 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sie, M. A1 - Susca, Tiziana A1 - Portal, Natalie Williams A1 - During, O. A1 - Fontana, Patrick A1 - Sjöström, C. ED - de Schutter, G. ED - de Belie, N. ED - Janssens, A. ED - van den Bossche, N. T1 - Influence of life span prediction on building component's LCA performance N2 - The life span of a building product is a key Parameter when it comes to Life Cycle Assessment (LCA) performance. Nevertheless, many uncertainties affect this parameter due to a lack of long-term performance data. The sensitivity of the LCA outcomes to this parameter has been studied within the framework of the FP7 project H-House (Healthier Life with Eco-innovative Components for Housing Constructions) funded by the European Commission. The paper Features two comparative studies conducted within the scope of this project: one for new construction and another for renovation. An innovative precast sandwich panel made of Textile Reinforced Concrete (TRC) and Foamed Concrete (FC), used for external walls in new construction, is compared with a steel reinforced concrete (SRC) wall of the same thermal resistance. For renovation, a novel halfsandwich panel made of Ultra-High-Performance-Concrete (UHPC) and Autoclaved Aerated Concrete (AAC) is compared with cladding having the same thermal performance. The Evaluation was conducted using a multi-criteria basis according to the LCA methodology (ISO 14040- 44). In each case, an identical life span for both scenarios leads to the fact that H-House components have a better environmental performance. The ISO 15686 and ist relevant parts have been considered for the estimation of the service life span. The sensitivity analysis shows the link between the impact savings of the innovative walls and the life span of the walls and their components. In particular, it was found that since both scenarios need to fulfil the same service during an identical reference period, and since some maintenance and replacement of materials are necessary over time for standard Solutions compared to the innovative ones, the chosen life span of the components plays a role of utmost importance. The sensitivity analysis discloses the effect of the assumptions on these aspects. T2 - XIV DBMC - 14th International Conference on Durability of Building Materials and Components CY - Ghent, Belgium DA - 29.05.2017 KW - LCA KW - Life span KW - TRC KW - UHPC KW - ISO 15686 PY - 2017 SN - 978-2-35158-159-9 VL - PRO 107 SP - 371 EP - 372 PB - RILEM Publications S.A.R.L. AN - OPUS4-40999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Wagner, M. R. A1 - Schlichting, S. A1 - Müßener, J. A1 - Hille, P. A1 - Teubert, J. A1 - Schörmann, J. A1 - Rosenauer, A. A1 - Eickhoff, M. A1 - Hoffmann, A. A1 - Callsen, G. A1 - Hönig, Gerald T1 - Suppression of the quantum confined Stark effect in polar III-nitride heterostructures N2 - One of the most significant limitations for the quantum efficiency of group III-nitride based light emitters is the spatial electron-hole separation due to the quantum-confined Stark effect (QCSE). To overcome this problem, Hönig et al. [1] proposed a novel concept, the Internal-Field-Guarded-Active-Region Design (IFGARD), which suppresses the QCSE for wurtzite crystals in the [0001] direction. Here, we show how encapsulating the active region by additional guard layers results in a strong reduction of the built-in electric field in c-plane wurtzite nanostructures. Even more importantly, we demonstrate the first experimental evidence for the successful realization of an IFGARD structure based on GaN/AlN heterostructures embedded in GaN nanowires. By means of power-dependent and time-resolved µ-photoluminescence (µ-PL) we experimentally proof the validity of the unconventional IFGARD structure. We managed to tune the emission of 4-nm-thick GaN nano-discs up to 3.32 eV at low excitation powers, which is just 150 meV below the bulk GaN bandgap. Our results demonstrate an almost complete elimination of the QCSE in comparison to conventional structures which show approximately 1 eV red-shifted emission. The suppression of the QCSE results in a significant increase of the radiative exciton decay rates by orders of magnitude and demonstrates the potential of IFGARD structures for future light sources based on polar heterostructures. [1] Hönig et al., Phys. Rev. Applied 7, 024004 (2017) T2 - International Conference on Nitride Semiconductors 12 of the European Materials Research Society CY - Strasbourg, France DA - 24.07.2017 KW - Nanophotonics KW - Piezoelectricity KW - Quantum confined stark effect KW - Semiconductor nanostructures KW - Spontaneous polarization PY - 2017 AN - OPUS4-41194 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Yin, Huajie A1 - Chapala, P. A1 - Bermeshev, M. A1 - Schönhals, Andreas A1 - Böhning, Martin T1 - Molecular Mobility and Physical Aging of a Highly Permeable Glassy Polynorbornene as Revealed by Dielectric Spectroscopy N2 - Polymeric membranes represent a cost- and energy efficient solution for gas separation. Recently superglassy polymers with high free volume outperform many conventional dense polymers in terms of gas permeability and selectivity. However, such polymers are prone to pronounced physical aging, resulting in a dramatic reduction in the gas permeability. Molecular mobility of polymer segments plays an important role in the physical aging and the gas transport performance of polymeric membranes. Molecular mobility and physical aging of a representative superglassy polynorbornene with very high gas permeability, PTCNSi2g, was monitored by using dielectric spectroscopy with state-of-the-art high-resolution analyzers. This work helps to shed some light on the structure−property relationship of superglassy polymers on a molecular level and to provide practical “design rules” for the development of high performance polymers for gas separation. KW - Molecular mobility KW - Gas separation membrane KW - Broadband dielectric spectroscopy KW - Polymer KW - Physical ageing PY - 2017 DO - https://doi.org/10.1021/acsmacrolett.7b00456 SN - 2161-1653 VL - 6 IS - 8 SP - 813 EP - 818 PB - ACS CY - Washington DC, USA AN - OPUS4-41354 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shamsuddoha, Md T1 - Critical Factors Affecting the Capacity of Cylindrical Grouted Connections in Offshore Energy Structures N2 - Current trend suggests that global energy consumption will increase in the future. This growing energy demand and advancement of technology lead to explore all potential offshore fossil and non-fossil energy sources, necessitating erection of exploration and production structures, rigs, platforms and towers, which are susceptible to adverse environmental conditions along with their maintenances. Cylindrical grouted joints provide suitable connections between steel substructure and foundation in these offshore platforms and wind structures especially monopiles for ease of installation. However, these are composite connections with exterior sleeve, interior pile and infill grout. The capacity of these connections is affected by number of factors. The literature over last four decades by numerous researchers has shown the development of these connections with increasingly higher capacities and influences on these capacities due to various factors. This paper provides a comprehensive review on the factors affecting the connection capacity along with technical challenges for the future. Critical aspects and shortcomings of the current connection systems and potential solutions may be sought after for these issues are also discussed. T2 - 36th International Conference on. Ocean, Offshore and Arctic Engineering CY - Trondheim, Norway DA - 25.06.2017 KW - Offshore wind energy KW - Grouted connection KW - Joint capacity KW - Shear keys PY - 2017 AN - OPUS4-42389 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Shamsuddoha, Md A1 - Hüsken, Götz A1 - Baeßler, Matthias A1 - Kühne, Hans-Carsten A1 - Thiele, Marc T1 - Critical factors affecting the capacity of cylindrical grouted connections in offshore energy structures N2 - Current trend suggests that global energy consumption will increase in the future. This growing energy demand and advancement of technology lead to explore all potential offshore fossil and non-fossil energy sources, necessitating erection of exploration and production structures, rigs, platforms and towers, which are susceptible to adverse environmental conditions along with their maintenances. Cylindrical grouted joints provide suitable connections between steel substructure and foundation in these offshore platforms and wind structures especially monopiles for ease of installation. However, these are composite connections with exterior sleeve, interior pile and infill grout. The capacity of these connections is affected by number of factors. The literature over last four decades by numerous researchers has shown the development of these connections with increasingly higher capacities and influences on these capacities due to various factors. This paper provides a comprehensive review on the factors affecting the connection capacity along with technical challenges for the future. Critical aspects and shortcomings of the current connection systems and potential solutions may be sought after for these issues are also discussed. T2 - 36th International Conference on Ocean, Offshore and Arctic Engineering CY - Trondheim, Norway DA - 25.06.2017 KW - Offshore wind energy KW - Grouted connection KW - Joint capacity KW - Shear keys PY - 2017 SN - 978-0-7918-5766-3 DO - https://doi.org/10.1115/OMAE2017-62510 VL - 3B SP - UNSP V03BT02A037, 1 EP - 10 AN - OPUS4-42387 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Aktuelle Entwicklungen und Herausforderungen bei Offshore-Gründungen mit Blick auf Forschung und Zulassung N2 - Der Seminarvortrag gibt einen Überblick über den Stand des Ausbaus Offshore Wind, der technischen Fragestellungen für die Tragstrukturen und Gründungen und die zu erwartenden Entwicklungen T2 - Geotechnische Seminarreihe des IBF/KIT CY - Karlsruhe, Germany DA - 23.11.2017 KW - Offshore-Gründungen KW - Windenergie PY - 2017 AN - OPUS4-43130 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reinsch, Stefan T1 - Sub-Tg relaxation in hydrous soda-lime-silicate and sodium-borosilicate glasses N2 - Water plays an important role for the depolymerization of silicate glasses which becomes noticeable by a distinct decrease of glass transformation temperature, Tg. Thus, it has a considerable influence on aging and fatigue as well as on sub-critical crack growth in glasses. In this connection also sub-Tg relaxation processes play a major role, but they are poorly investigated in glasses with high contents of structural bonded water. Therefore, soda-lime-silicate and sodium-borosilicate glasses with water contents up to 5 wt.% H2O were investigated by differential thermal analysis and sphere penetration viscometry, as well as internal friction measurements. The latter was applied to study network related relaxation mechanisms (α-relaxation) in the range of glass transition, as well as faster relaxation modes occurring at lower temperatures (β-, γ- relaxation). Total water content and concentrations of H2O molecules (CH2O) and OH groups (COH) in the glasses were determined by infrared spectroscopy. For low water contents two sub-Tg internal friction peaks were observed and assigned to the low-temperature motion of alkali ions (γ-relaxation) and cooperative movements of dissimilar mobile species under participation of OH at higher temperature (βOH relaxation). For large water contents, where significant amounts of molecular water are evident, a low temperature shoulder appears on the β-relaxation peak. This emerging relaxation mode (βH2O relaxation) was assigned to the motions of H2O molecules. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 28.05.2017 KW - Water-bearing glasses KW - Mechanical loss spectroscopy KW - Relaxation PY - 2017 AN - OPUS4-40810 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kiefer, P. T1 - Viscosity of water bearing glasses in the glass transition range – Phosphates vs. silicates and borates N2 - Water has a strong impact on the viscosity and the transition temperature of oxide glasses. It acts as a fluxing agent, reducing viscosity particularly in the glass transition range, and by that flattening the viscosity-temperature curve and decreasing the fragility of hydrous glass melts. This general behavior is found for silicate and borate as well as in borosilicate compositions. However, there is still a lack of data with respect to hydrous phosphate glasses. Here, we study the influence of structural water on the viscosity of Li2O-MgO-(Al2O3-)P2O5 glasses. The glasses were synthesized in an internally heated pressure vessel (IHPV) at a pressure of 0.5 GPa. The selected pressure allows for the synthesis of glass specimens with water contents of several wt.%. The viscosity measurements were carried out in the glass transition range, i.e. log η ≈ 10-13 (η in Pa s), using a sphere penetration viscometer. The measured data agree with glass transition temperatures measured by differential thermo analysis. First results further suggest that the fragility of the analyzed phosphates decreases with increasing water content. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 28.05.2017 KW - Water-bearing glasses KW - Viscosity PY - 2017 AN - OPUS4-40812 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waurischk, Tina T1 - New device for inert crack growth measurements in ultra-strong glasses N2 - The practical strength of glasses under ambient conditions is substantially lower compared to its intrinsic strength because of sub-critical crack growth (SCCG) from microscopic flaws. While SCCG is related to the humidity of the ambient atmosphere, leading to stress corrosion phenomena, the detailed kinetics are still not fully understood. To get better insight to the contribution of water on the crack-tip, highly water bearing glasses will be investigated by a new device for inert SCCG-measurements using double cantilever beam (DCB) geometry specimens. This device was designed to investigate the stress intensity factor in modus I and crack velocity in vacuum, but different atmospheres can also be introduced. For validation of the new device, first experiments were performed on microscope slides as well as on a soda-lime silicate and a borosilicate crown glass. The results achieved will be presented in comparison to the published results of Wiederhorn. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 29.05.2017 KW - Double cantilever beam KW - DCB KW - Crack intensity factor KW - Crack growth velocity KW - Glass PY - 2017 AN - OPUS4-40680 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Welter, T. T1 - Glass structures with low helium and hydrogen permeability N2 - An efficient energy provision using fuel cells is linked to effecitve hydrogen storage capabilities. Because of its low intrinsic hydrogen permeability, glass has a huge potential in modern concepts of hydrogen storage. Previous studies on oxidic glasses showed an empirical connection between glass composition and gas permeation, which was mainly derived from the behavior of silica glass. In this study we focus on the relationship between topologic (free volume; network polymerization) and thermodynamic (configurational entropy) parameters. The comparison of three glasses within the meta (earth-) alkaline alumino silicate system to silica glass shows that an increase of the atomic packing factor (APF) does not necessarily decrease the permeability. Furthermore, the results suggest a connection between ΔCp at Tg and hydrogen permeability of the glass. All experiments were performed assuming that chemical hydrogen solubiltity in glass is negligible at temperatures well below the glass transition temperature. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 29.05.2017 KW - Hydrogen permeability KW - Glass composition KW - Atomic packing factor KW - Configurational entropy KW - Diffusion coefficient PY - 2017 AN - OPUS4-40488 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Marzok, Ulrich T1 - Measurement of H2 permeability of glasses with VHE powder method N2 - The development of glassy hydrogen barriers requires the determination of low H2 permeabilities. Previous studies and numerical simulations have shown that the VHE powder method (vacuum hot extraction with mass spectrometric gas detection) is suitable for this purpose. The measured isothermal gas emission is fitted to a classical diffusion model for spherical particles from which the diffusion coefficient of the glass is calculated. The H2 permeability is determined by means of the solubility determined from the same measurement data. This presentation is referring to the optimization of the method regarding sample preparation and measurement data evaluation using suitable experimentally determined particle size distributions is reported. For quartz glass, it is shown that the accuracy of classical measuring methods is achieved with the VHE powder method. Furthermore, other examples of substantially gas-tighter glasses are given. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 29.05.2017 KW - Hydrogen permeation KW - Glass KW - Vacuum hot extraction KW - Powder method KW - Diffusion coefficient PY - 2017 AN - OPUS4-40441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Waurischk, Tina T1 - New device for inert sub-critical crack growth: measurements in crystallized glasses N2 - Compared to its intrinsic strength, the practical strength of glasses is substantially lowered by microscopic flaws. Their sub critical growth from the surface is strongly affected by ambient humidity. A new device was designed to enable the observation of sub critical crack growth (SCCG) in vacuum and controlled atmosphere. It allows measurements in transparent and semi-transparent materials in double cantilever beam (DCB) geometry. The aim of the present work is to study the effect of crystals on crack growth. T2 - 12th International Symposium on Crystallization in Glasses and Liquids CY - Segovia, Spain DA - 10.09.2017 KW - Double cantilever beam KW - DCB KW - Crack intensity factor KW - Crack growth velocity KW - Glass KW - Glass ceramic PY - 2017 AN - OPUS4-41995 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Müller, Ralf A1 - Körner, S. T1 - Dissolution and reprecipitation of silver in sintering silver-glass dispersions N2 - Electric contacts based on silver-glass dispersions are key components in optoelectronic microsystems and control modules for medical, information & communication and energy technology in our networked society. Driven by the complexity of modern production processes and ever shorter time-to-market requirements, the fast and specific development of tailored silver-glass dispersions has become a bottleneck of technology development. Nevertheless, the underlying mechanisms of silver dissolution, transport, and reprecipitation, and the resulting micro structure evolution during firing are poorly understood. The broad literature on the precipitation of colloidal silver particles and the related processes of silver dissolution and diffusion mostly refer to very small volume fractions of silver. Transferring these results to the sintering of glass-containing silver dispersions, is therefore highly questionable. In this case, silver dissolution, electrical contact between silver particles, transport and reprecipitation take place under special conditions. This includes short diffusion lengths (particle size < 10 μm), the presence of three-phase contacts silver - glass - sintering atmosphere, as well as silver reprecipitation at the sintering contacts as the driving force of silver transport. Here, a dynamic balance of the silver concentration can be expected to result from the ratio between silver dissolution and reprecipitation. The aim of the project is to gain basic insight into the mechanisms of dissolution, transport and reprecipitation of silver in sintering silver glass dispersions. In this context, the main focus is on gaining basic knowledge about the dissolution of metallic silver in low melting oxide glasses as the limiting factor of the sintering of silver-glass composites. In particular, we will strive to gain insight into the effect of the oxygen content of the sintering atmosphere, of the oxygen dissolved in the silver particles, of silver oxide on the surface of the silver powder, of the electric contact between the silver particles, as well as the basicity of the glass. Furthermore, we strive for insights into the silver mobility and the silver concentration that can be attained (silver solubility) in oxide glasses with a low melting point. Summing up all these aspects, a closed explanatory model for silver dissolution, transport and reprecipitation during the sintering of glass silver dispersions will be introduced. T2 - DFG Begutachtungskolloquium (PAK 949/1 und PAK 950/1) CY - Bonn, Germany DA - 07.03.2017 KW - Sintering KW - Silver KW - Glass KW - Solubility KW - Reprecipitation PY - 2017 AN - OPUS4-44227 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blaeß, Carsten T1 - Crack healing in glass matrix composites N2 - Partially crystalline glasses are predominantly used as solid oxide fuel cell (SOFC) sealants due to their superior long term durability. However, cracks caused by thermal cycling still remain a substantial bottleneck in developing durable SOFC sealants inasmuch as, in contrast to crystal free glasses, large crystal volume fractions can retard healing. Hence, the basic understanding of crack healing in glassy crystalline materials and the effects of micro structure are important for finding optimum micro structures for both, durability and crack healing. For studying these effects, several model glass matrix composites (GMC), for which simultaneous crystal growth and crack healing can be excluded, have been synthesized. Sodium calcium silicate glass – zirconia GMC turned out to provide sufficiently homogeneous, dense and durable model GMC for our studies. The microstructure of this GMC shows large crystal free glassy regions embedded in network of finely dispersed ZrO2 nanoscale crystals. Whereas the glassy regions allow easy local crack healing, the network of dispersed crystals increases the effective viscosity on a global scale. This effect substantially retards crack broadening during later healing stages, which often ends up in large pores. Therefore, this type of microstructure seems to be an interesting candidate for crack healing optimized sealants. T2 - Crystallization 2017 CY - Segovia, Spain DA - 10.09.2017 KW - Glass KW - Glass ceramic KW - Crack healing KW - Microstructure PY - 2017 AN - OPUS4-42291 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blaeß, Carsten T1 - Crack healing in glasses and glass matrix composites N2 - Fundamental understanding of crack healing in glassy crystalline materials is very important for solid oxide fuel cell (SOFC) sealants, since cracks caused by sealing or thermal cycling still remain a substantial bottleneck in developing durable SOFC. Previous studies on soda lime silicate glass [Sin14] showed that crack healing is driven by viscous flow and that healing progress is proportional to time t and inverse viscosity η. This finding would allow to present healing data of a given glass for different temperatures in a master curve healing progress versus t/η. Such master curves would be a helpful tool in understanding crack healing kinetics. Against this background, crack healing in non-crystallizing sodium calcium silicate (NCS) and sodium borosilicate glasses (NBS) have been studied. Moreover, to evaluate the influence of micro structure in crystallized glass on crack healing process, glass matrix composites (GMC) were prepared from NCS and zirconia as inert ceramic filler material mimicking a partially crystalline micro structure. By this way, the micro structure can be kept constant during crack healing. Cracks were generated by Vickers indention and healed isothermally at different temperatures. Crack healing progress was monitored by optical and electron microscopy. Results show that the above mentioned proportionality actually applies for the studied glasses for which such a master curve could be obtained. In comparison to a non-crystallized glass, the effective viscosity of GMC is increased by the rigid filler content. This effect substantially retards crack broadening during later healing stages, which often ends up in large pores. On the other hand, local viscous crack healing is still possible in larger glassy regions. This behavior seems to be very interesting for crack healing optimized micro structures. T2 - Crystallization 2017 CY - Segovia, Spain DA - 10.09.2017 KW - Glass KW - Glass ceramic KW - Crack healing KW - Microstructure PY - 2017 AN - OPUS4-42285 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Blaeß, Carsten T1 - Master curve for crack healing in silicate glasses N2 - Fundamental understanding of crack healing in glassy crystalline materials is very important for many applications, especially for solid oxide fuel cells (SOFC) sealants since cracks caused by mechanical stress or thermal cycling still remain a substantial bottleneck in developing durable SOFC. Previous studies on soda lime silicate glass published by Singh showed that crack healing is driven by viscous flow. He postulated that the healing progress is proportional to time, t, and the inverse viscosity. For a given glass, this finding would allow to present data of crack healing measured at different temperatures in a master curve, if the healing progress is plotted versus t/. Such master curves would be a helpful tool in understanding crack healing kinetics. To verify the applicability of such master curves, crack healing in non-crystallizing soda-lime-silicate (NCS) and sodium-borosilicate glasses (NBS) was studied. Cracks were generated by Vickers indention and healed isothermally at different temperatures. Crack healing progress was monitored by optical and electron microscopy. The results show that the above mentioned proportionality applies to the two glasses and the afore developed master curve could be obtained in both cases. T2 - Crystallization 2017 CY - Segovia, Spain DA - 10.09.2017 KW - Glass KW - Crack healing KW - Vickers PY - 2017 AN - OPUS4-42293 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stajanca, Pavol A1 - Woyessa, G. A1 - Schukar, Marcus A1 - Bang, O. A1 - Krebber, Katerina T1 - Response of microstructured plastic optical fiber Bragg grating to gamma radiation N2 - Response of PMMA-based plastic optical fiber Bragg grating (FBG) to gamma radiation is investigated for the first time. FBG wavelength shift as large as 150 pm is observed for irradiation to 18 kGy. T2 - 5th Workshop on specialty optical fibers and their applications CY - Limassol, Cyprus DA - 11.10.2017 KW - Fiber Bragg gratings KW - Optical sensing and sensors KW - Plastic optical fibers KW - Gamma radiation PY - 2017 SP - Poster 19, 1 EP - 2 AN - OPUS4-42586 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Stajanca, Pavol T1 - Response of microstructured plastic optical fiber Bragg grating to gamma radiation N2 - Response of PMMA-based plastic optical fiber Bragg grating (FBG) to gamma radiation is investigated for the first time. FBG wavelength shift as large as 250 pm is observed for irradiation to 20 kGy. T2 - 5th Workshop on specialty optical fibers and their applications (WSOF2017) CY - Limassol, Cyprus DA - 11.10.2017 KW - Fiber Bragg gratings KW - Optical sensing and sensors KW - Plastic optical fibers KW - Gamma radiation PY - 2017 AN - OPUS4-42585 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - RPRT A1 - Becker, Ben A1 - Mair, Georg W. A1 - Schoppa, Andre A1 - Duffner, Eric A1 - Szczepaniak, Mariusz A1 - Klauke, Andre A1 - Lenz, Stefan A1 - Lehr, Christian A1 - Hoffmann, Martin A1 - Gregor, Christian ED - Mair, Georg W. T1 - CryoCode: Kryodruck Tanksystem und Betankung – Validierung bis zum Normierungsvorschlag N2 - Entwicklung und Validierung eines Kryodruck-Tanksystems für Wasserstoff-Fahrzeuge. Darstellung der Versuchsergebnisse und des Normierungsvorschlags. KW - Kryodruck KW - Wasserstoff KW - Druckbehälter KW - Composite KW - Normierungsvorschlag PY - 2017 SP - 1 EP - 56 AN - OPUS4-40714 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schoppa, Andre A1 - Szczepaniak, Mariusz A1 - Mair, Georg W. ED - Schoppa, Andre T1 - Die Anwendung der hydraulischen Prüfverfahren in der Praxis Teil 1: Die hydraulische Berstprüfung N2 - Um die Resultate aus den hydraulischen Prüfungen statistisch bewerten zu können, benötigt man Prüfergebnisse, die auf reproduzierbaren Prüfverfahren basieren. Dabei geht es nicht nur um ein funktionierendes Qualitätsmanagementsystem im Prüflabors, sondern vornehmlich um die Reduzierung des Einflusses der Prüftechnik und des Prüfverfahrens auf die Streuung der Ergebnisse. Dieser Einfluss kann erst durch ins Detail konkretisierte Prüfungsanforderungen minimiert werden. Dieser Anforderung entsprechend wurde ein Verfahren beschrieben, das den Spielraum bei der Durchführung der hydraulischen Berstprüfung verringert und somit eine Streuung der Ergebnisse garantiert, die annähernd ausschließlich aus den Prüfmustern kommt. Die Prüfmusterdokumentation spielt dabei eine zentrale Rolle. Zwischen den hydraulischen Prüfungen im Zuge der Zulassung eines Baumusters und den hydraulischen Prüfungen zur Prüffristenfestlegung liegt eine Zeitspanne von mehreren Jahren. Um die Prüfergebnisse auch nach einer längeren Preisfestlegung (z.B. 10 Jahre) miteinander vergleichen zu können, müssen die zerstörenden Prüfungen reproduzierbar durchgeführt und vollständig dokumentiert und archiviert werden. Die Prüfung an neuen Materialien oder neuen Produkten erfordert eine moderne Prüftechnik, die sich mit dem Stand der Technik stetig weiterentwickeln muss. Demzufolge ist die zunehmende Automatisierung in der Prüftechnik ein wichtiger Schritt um Prüfungen reproduzierbarer durchzuführen. Wie ein konkretisierte Verfahren zur hydraulischen Lastwechselprüfung in der Praxis aussieht, wird in einem nächsten Beitrag betrachtet. Dabei wird ebenfalls Bezug zur verwendeten Prüftechnik genommen unter dem Hauptgesichtspunkt, welche Anforderungen in der Bundesanstalt für Materialforschung und -prüfung BAM an eine moderne Lastwechselanlage zur Prüfung von Druckbehältern bis 1200 bar gestellt werden. KW - Druckbehälter KW - Berstprüfung KW - Hydraulische Prüfeinrichtung KW - Prüffristenfestlegung PY - 2017 SN - 2191-007 VL - 7 IS - 5 SP - 25 EP - 30 PB - Springer VDI Verlag CY - Düsseldorf AN - OPUS4-41518 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg W. A1 - Becker, Ben A1 - Duffner, Eric A1 - John, Sebastian T1 - Composite storage systems for CGH2- systematic improvement of RC&S N2 - Conventional approval requirements exclusively ask for minimum strength values, which have to be met. The probabilistic approach estimates how likely none of the comparatively manufactured units fails during operation. Both questions are juxtaposed and compared here with respect to the load cycle tests. The influence of the sample sizes is discussed additionally. T2 - 10th INTERNATIONAL CONFERENCE ON SUSTAINABLE ENERGY & ENVIRONMENTAL PROTECTION CY - Bled, Slovenia DA - 27.06.2017 KW - Probabilistic KW - Hydrogen KW - Composite KW - Cylinder KW - Regulations KW - Load cycles KW - GTR 13 PY - 2017 AN - OPUS4-41677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg W. T1 - The UN-Service Life Test Procedure & Lebensdauerüberwachung Typ II N2 - Der Vortrag führt in die Vorgaben der UN-Modellvorschriften ein, ein „Gas cylinders - service life testing for cylinders and tubes of composite construction“ zu gewährleisten. Hierzu werden kurz die betroffenen Umschließungen vorgestellt und die Interaktion von relevanten Regelwerksänderungen und der Beauftragung von ISO, einen TR hierzu zu erstellen, erläutert. Dies wird ergänzt durch eine zusammenführende Darstellung der Veränderungen im Regelwerk zum Thema und den vorbereitenden und begleitenden Maßnahmen durch die BAM über die letzten fasst 20 Jahre. Die im Regelwerk vorgeschlagene Maßnahme, zwischen Auslegungslebensdauer und Betriebslebensdauer zu unterscheiden, wird erläutert und begründet. Die Interaktion mit der Genehmigung einer Frist von 10 Jahren durch die BAM für die wiederkehrende Prüfung wird dargestellt. Am Beispiel der umfangsgewickelten Stahlflaschen für den Wasserstofftransport in Batteriefahrzeugen wird dargestellt, wie das dt. Verfahren in der Praxis aussieht. Hierzu werden die Prüfergebnisse und die daraus bzgl. der Lebensdauerüberwachung gezogenen Schlüsse erläutert. Der Vortrag schließt mit einem Ausblick zur Verwendung des BAM-Verfahrens zur unmittelbaren Anwendung und zur Bewertung von für die Zukunft angestrebten ZfP-Verfahren. T2 - BAM-DIN-IGV-DVFG Gespräch 2017 CY - DIN Berlin, Germany DA - 15.02.2017 KW - Auslegungslebensdauer KW - Betriebslebensdauer KW - Prüffristenfestlegung KW - Probabilistischer Ansatz PY - 2017 AN - OPUS4-39181 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Saul, Herbert A1 - Mair, Georg W. T1 - Zuständigkeit im Gefahrguttransport - Formale Umsetzung nach nationalem Verwaltungsrecht N2 - Der Vortrag fasst zunächst die Arbeitsgrundlage des Verwaltungshandelns im Gefahrguttransport zusammen: die internationalen Transportvorschriften und die nationalen Verordungen auf Basis des GGBefG. Danach geht er auf die wichtigsten verwaltungsrechtlichen Begrifflichkeiten und Zusammenhänge verschiedener Gesetze ein. Darauf aufbauend wird der Ablauf zur Bearbeitung eines Verwaltungsvorgangs und die Schnittstelle zu Z.01 erläutert. T2 - Colloquium der Abteilung 3 CY - BAM, Berlin, Germany DA - 16.02.2017 KW - Völkerrechtliche Verträge KW - Gesetzesgrundlagen KW - Zuständigkeit KW - Verwaltungsvorgang KW - Frist KW - Verwaltungsakt KW - Bescheid PY - 2017 AN - OPUS4-39284 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Mair, Georg W. A1 - Becker, Ben T1 - Monte-Carlo-analysis of minimum load cycle requirements for composite cylinders for hydrogen N2 - Existing regulations and standards for the approval of composite cylinders in hydrogen service are currently based on deterministic criteria (ISO 11119-3, UN GTR No. 13). This paper provides a systematic analysis of the load cycle properties resulting from these regulations and standards. Their characteristics are compared with the probabilistic approach of the BAM. Based on Monte-Carlo simulations the available design range of all concepts is compared. In addition, the probability of acceptance for potentially unsafe design types is determined. T2 - ICHS 2017 CY - Hamburg, Germany DA - 11.09.2017 KW - Monte-Carlo KW - Hydrogen KW - Regulations KW - Probabilitic approach PY - 2017 SP - ID 202, 1 EP - 11 PB - HySafe CY - Hamburg AN - OPUS4-41944 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - BOOK A1 - Mair, Georg W. T1 - Safety Assessment of Composite Cylinders for Gas Storage by Statistical Methods N2 - Featuring a detailed analysis of current approval requirements and the relevant safety assessment methods for gas cylinders in general and with main focus on composite cylinders for storing ompressed natural gas and hydrogen, this book demonstrates how current regulations and standards limit the ability to reduce cost and weight. Based on this data, it then highlights the potential offered by the proposed approval procedure based on probabilistic safety assessment. After addressing the economic potential of probabilistic safety assessments, the book details working procedures and improving cycles and (slow) bursts as methods for assessing residual strength. It then discusses methods for statistically evaluating test data, as well as sample- size and distribution character considerations. A definition of sample strength is elaborated in terms of the performance sheets developed by the author. On this basis, it discusses safety as a property of service life and interpreted as an issue of degradation, and explores aspects of artificial aging for simulating the end-of-life reliability level. Lastly, the book considers control and inspection aspects: quality of production, degradation prediction using destructive sample tests parallel to operation, retesting periods and correcting for underand overestimates of safe lifetime. Presented in schematic diagrams, illustrations and tables, this information enables manufacturers and operators to use this new approach in practice and supports the improvement of current regulations and standards. KW - Probabilistic KW - Statistics KW - Slow burst testing KW - Fire engulfment KW - Crash loads KW - Degradation KW - Production scatter KW - Operational loads KW - Residual strength KW - Service life KW - Design life KW - Safety KW - Risk KW - Consequences KW - Failure rate KW - Survival rate KW - Confidence level KW - Acceptance rate PY - 2017 SN - 978-3-319-49708-2 SN - 978-3-319-49710-5 DO - https://doi.org/10.1007/978-3-319-49710-5 VL - 2017 SP - I ; 1 EP - XXI; 269 PB - Springer International Publishing CY - Cham, Switzerland ET - 1. AN - OPUS4-42324 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schoppa, Andre A1 - Szczepaniak, Mariusz A1 - Mair, Georg W. ED - Schoppa, Andre T1 - Die Anwendung der hydraulischen Prüfverfahren in der Praxis - Teil 2 Die hydraulische Lastwechselprüfung N2 - Die bisherigen Erfahrungen mit der bestehenden Impulsprüfanlage PN020 der BAM zeigen Potential für Verbesserungen auf. Dies betrifft insbesondere die Aspekte nutzbares Impulsvolumen, Wartungsaufwand und Stillstandszeiten, sowie Abmessungen und Gestaltung der Prüfkammer hinsichtlich Nutzraum und Handling der Prüfmuster. Im Zuge eines optimierten Anlagekonzeptes besteht großes Interesse an einer flexiblen Neuausrichtung der Druckerzeugung. Eine moderne Prüfanlage sollte in der Lage sein, die zu bewegenden Massen an die gewünschte Prüfaufgabe und den jeweils benötigten Volumenbedarf anzupassen. Die technische Lösung für die Druckerzeugung sollte deshalb modular gestaltet sein, sodass zusätzlich benötigtes Fördervolumen im Bedarfsfall nachgerüstet werden kann. Ein anderes Konzept als eines, das auf Druckübersetzern basiert, scheidet für Extremtemperaturprüfungen aus, da das vorzutemperierende Medium hierzu in einer Säule pendeln und nicht zirkulieren darf. Wesentlicher Aspekt der Modularität ist die Redundanz bei Teillast (reduzierter Volumenbedarf - Arbeitsfähigkeit bleibt mit Einschränkung erhalten). Es wird davon ausgegangen, dass einzelne Druckerzeugungs-/Antriebseinheiten so demontiert, repariert oder ausgetauscht werden können, dass die Nicht-Verfügbarkeit der gesamten Anlage auf den Ein- und Ausbau von Elementen der Anlage und Ausfälle in der Steuerung beschränkt bleibt. Auch im teil-demontierten Zustand sollte die Anlage mit eingeschränkter Leistungsfähigkeit grundsätzlich einsetzbar sein. Die Wartungskosten sollen durch die Verwendung von identischen und kleineren Druckerzeugereinheiten „von der Stange“ gesenkt werden. Eine moderne Anlage wäre zur Verbesserung der Diagnosemöglichkeiten mit erheblich mehr Sensorik auszurüsten. Die Druckerzeugung muss mit der Art der Medienkonditionierung kompatibel gestaltet sein. Das heißt, das Prüfmedium sollte unabhängig von der Umgebungsluft aktiv temperiert werden können, um die Konditionierzeiten bis zum Prüfungsstart zu verkürzen und um einen Temperaturanstieg infolge der Reibung zu verringern. Die „Prüfkammer“ sollte keine starre Kammer im herkömmlichen Sinne mehr sein. Stattdessen ist eine thermisch isolierte und mechanisch hoch belastbare Versuchsfläche aufzubauen, auf der sowohl mechanische Schutzelemente (vergl. aktueller Berstkäfig) wie auch mobile Isolierhauben verwendet werden können. Wesentlich ist eine Optimierung einer solchen Anlage auf die eingangs erwähnte Reproduzierbarkeit von Prüfprozeduren und die Vergleichbarkeit der Prüfergebnisse mit Blick auf die statistische Auswertung. Hierzu sollten eine möglichst exakte Regelung, eine statistische Auswertung der Duckextremwerte (zumindest in Klassen), eine Aufzeichnung der Temperatur- und Feuchtewerte sowie des geförderten Volumens jedes Zyklusses und verschiedene Methoden der Leckerkennung/automatischen Versuchsabbruches selbstverständlich implementiert sein. KW - Druckbehälter KW - Lastwechselprüfung KW - Hydraulische Prüfeinrichtung PY - 2017 SN - 2191-007 VL - 7 IS - 7/8 SP - 28 EP - 34 PB - Springer VDI Verlag CY - Düsseldorf AN - OPUS4-41519 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yin, Huajie T1 - Molecular mobility of super glassy polymers for gas separation membranes investigated by dielectric spectroscopy N2 - Super glassy polymers such as poly(trimethylsilylpropyne) (PTMSP) or polymers with intrinsic microporosity (PIMs) play an important role in the current development of membrane materials for gas separation because of their high permeability and selectivity. Unfortunately, such materials which have a high fractional free volume (FFV) are prone to pronounced physical aging. The initial microporous structures approach a more dense state via local chain rearrangements which results in a dramatic reduction in the gas permeability. For the first time, broadband dielectric spectroscopy was employed to investigate the molecular dynamics of two representative groups of super glassy polymers: PIMs (PIM-1 & PIM-EA-TB) and Si-containing polynobornenes (PTCNSi1 & PTCNSi2). The dielectric behavior of the solution-cast polymeric films was measured by isothermal frequency scans during the different heating cycles in a broad temperature range. Structural relaxation of the films was observed during the measurements. Molecular relaxation processes following Arrhenius behavior with unusually high activation energies were observed for all the investigated polymers. The PIMs showed furthermore a significant conductivity in the glassy state which is explained with the formation of local intermolecular agglomerated structures due to interaction of π-electrons in aromatic moieties of the polymer backbone. T2 - 8th International Discussion Meeting on Relaxations in Complex Systems CY - Wisla, Poland DA - 23.07.2017 KW - Broadband dielectric spectroscopy KW - Molecular mobility KW - Physical aging KW - Membranes KW - Gas separation PY - 2017 AN - OPUS4-41162 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Konnertz, Nora A1 - Ding, Yi A1 - Harrison, W.J. A1 - Budd, P.M. A1 - Schönhals, Andreas A1 - Böhning, Martin T1 - Molecular mobility and gas transport properties of nanocomposites based on PIM-1 and polyhedral oligomeric phenethyl-silsesquioxanes (POSS) N2 - Polymers with intrinsic microporosity (PIMs) are of great interest in the field of gas separation membranes. Already the first synthesized PIM-1 shows extraordinary permeability and selectivity. Unfortunately, PIM-1 is susceptible to physical aging and thus gradually loses its outstanding properties. In this study a polyhedral oligomeric silsesquioxane with phenethyl substituents (PhenethylPOSS) was used as a nanofiller (0–40 wt%) in the PIM-1 matrix to potentially improve the gas transport properties and prevent physical aging. The molecular mobility of the solution-cast nanocomposite films was analyzed by Broadband Dielectric Spectroscopy (BDS). Furthermore, gas permeability was determined with the time lag method (0–20 bar upstream pressure) at 35 °C for N2, O2, CH4 and CO2. KW - Broadband Dielectric Spectroscopy KW - Gas separation KW - Gas permeation KW - Polymers of intrinsic microporosity KW - Nanocomposite KW - POSS KW - PIM-1 PY - 2017 DO - https://doi.org/10.1016/j.memsci.2017.02.007 SN - 0376-7388 SN - 1873-3123 VL - 529 SP - 274 EP - 285 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-39169 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Yin, Huajie T1 - Molecular Mobility and Physical aging of SuperGlassy Polymers for Gas Separation Membranes as revealed by Dielectric Spectroscopy N2 - Polymeric membranes represent a cost- and energy efficient solution for gas separation. Recently superglassy polymers with high free volume outperform many conventional dense polymers in terms of gas permeability and selectivity. However, such materials with a high fractional free volume (FFV) are prone to pronounced physical aging. The initial microporous structures approach a denser state via local chain rearrangements which results in a dramatic reduction in the gas permeability. For the first time, dielectric spectroscopy with state-of-the-art high-resolution analyzers was employed to investigate the molecular mobility and physical aging of two representative groups of superglassy polymers: PIMs (PIM-1 & PIM-EA-TB) and Si-containing polynobornenes (PTCNSi1 & PTCNSi2). The dielectric behavior of the solution-cast polymeric films was measured by isothermal frequency scans during the different heating cycles in a broad temperature range. Structural relaxation of the films was observed during the measurements. Multiple dielectric processes following Arrhenius behavior were observed for all the investigated polymers. Moreover, they all showed conductivity in the glassy state. The significant increase in the conductivity with increasing temperature especially for PIMs is explained in terms of the formation of local intermolecular agglomerated structures due to interaction of π-electrons in aromatic moieties of the polymer backbone. T2 - 8th International Conference on Advanced Fibers and Polymer Materials CY - Shanghai, China DA - 08.10.2017 KW - Physical aging KW - Membranes KW - Broadband dielectric spectroscopy KW - Gas separation KW - Molecular mobility PY - 2017 AN - OPUS4-42877 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Baeßler, Matthias T1 - Untersuchungen zu Tragstrukturen für die Energiewende N2 - Die BAM ist vielfältig mit der Untersuchung von für die Energiewende relevanten Strukturen beschäftigt. Aus dem speziellen Blickwinkel des FB 7.2 werden im Vortrag die Aktivitäten FE, PAZ und BI umfassend für Studenten der BU Weimar dargestellt. T2 - Einblick (#53) CY - Bauhaus Universität Weimar, Germany DA - 19.01.2017 KW - Tragstrukturen KW - Energiewende PY - 2017 AN - OPUS4-39376 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -