TY - CONF A1 - Fuggini, C. A1 - Zangani, D. A1 - Wosniok, Aleksander A1 - Krebber, Katerina A1 - Franitza, P. A1 - Gabino, L. A1 - Weigand, F. T1 - Innovative approach in the use of geotextiles for failures prevention in railway embankments T2 - Transportation Research Procedia N2 - Maintenance and renewal costs of a typical railway, track and substructure represents 50–60% of the total costs of such infrastructure over its entire service life. Innovations in track and substructure are therefore fundamental to achieve a significant impact on the overall cost reduction for the railways. Therefore new solutions for track improvements that are effective and that can minimize the interruption of traffic are needed. Moreover, failures of railway embankments happened recently in different regions of the world. Such events, such as the one happened in UK in February 2013 (http://www.bbc.co.uk/news/uk-england-south-yorkshire-21441070), are showing the importance of monitoring track and infrastructure coupled with the use of numerical models for the localization of the critical areas and the design of appropriate countermeasures. Indeed embankment failures, landslides and uneven settlements and similar events are becoming much more common than in the past due to climate changes, and this requires the infrastructure managers to look from a different perspective infrastructure maintenance issues. What was previously consider as “extreme” is now “common” and thus actions need to be taken to be ready when such events will happen. The aim is to mitigate their effects on the infrastructure and to minimize disruptions to train services and reduce maintenance costs to restore the normal service conditions. If this mental change happens, then the need for solutions and techniques for global asset monitoring and ground stabilization will probably increase. Among the others, geotextiles and geogrids for soil reinforcement used in combination with condition monitoring techniques have the potential for minimizing catastrophic events, whilst at the same time providing a good balance among costs and benefits (i.e. sustainability). The paper describe a case study where the use of multifunctional geotextiles, able to provide both strengthening and monitoring functions, has been tested along a railroad near the city of Chemnitz (Germany). The results are here reported to show the potential use and the innovative aspect of this solution. T2 - 6th Transport Research Arena (TRA) CY - Warsaw, Poland DA - 18.04.2016 KW - smart geotextile KW - failure prevention KW - railway embankment KW - fiber optic sensor KW - distributed sensor PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-379256 DO - https://doi.org/10.1016/j.trpro.2016.05.154 VL - 14 SP - 1875 EP - 1883 PB - Elsevier B.V. AN - OPUS4-37925 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schukar, Vivien A1 - Köppe, Enrico A1 - Hofmann, Detlef A1 - Westphal, Anja A1 - Sahre, Mario A1 - Gong, Xin A1 - Bartholmai, Matthias A1 - Beck, Uwe T1 - Magnetic field detection with an advanced FBG-based sensor device T2 - 30th Eurosensors Conference - EUROSENSORS 2016 N2 - A high-performance fiber Bragg grating-based (FBG) sensor device has been developed for the detection of small magnetic fields. Based on a smart multilayer jacket around the fibre over the physical length of the FBG, magnetic fields generated by rotating machine parts, power generators or power cable can be easily detected, analysed and evaluated. Consequently, this innovative, on-line and non-contact inspection method results in an increase in quality and reliability of high-performing machine parts, devices and cables. The basic physical principle is based on a magnetostrictive multilayer system that strains the high-resolution FBG element in presence of magnetic fields. Subsequently, a fixed relationship between induced magnetic field and wavelength change of the FBG element describes the characteristic sensitivity curve. Intensive tests regarding characterisation of this magnetic field FBG sensor have been carried out and its performance has been evaluated. T2 - 30th Eurosensors Conference, EUROSENSORS 2016 CY - Budapest, Hungary DA - 04.09.2016 KW - Fiber Bragg grating KW - Magnetostriction KW - Strain KW - Magnetic field PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-376703 DO - https://doi.org/10.1016/j.proeng.2016.11.445 SN - 1877-7058 VL - 168 SP - 1270 EP - 1274 PB - Elsevier Ltd. AN - OPUS4-37670 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Petrat, T. A1 - Graf, B. A1 - Gumenyuk, Andrey A1 - Rethmeier, Michael ED - Schmidt, M. ED - Vollertsen, F. ED - Arnold, C. B. T1 - Laser metal deposition as repair technology for a gas turbine burner made of Inconel 718 T2 - Physics Procedia N2 - Maintenance, repair and overhaul of components are of increasing interest for parts of high complexity and expensive manufacturing costs. In this paper a production process for laser metal deposition is presented, and used to repair a gas turbine burner of Inconel 718. Different parameters for defined track geometries were determined to attain a near net shape deposition with consistent build-up rate for changing wall thicknesses over the manufacturing process. Spot diameter, powder feed rate, welding velocity and laser power were changed as main parameters for a different track size. An optimal overlap rate for a constant layer height was used to calculate the best track size for a fitting layer width similar to the part dimension. Deviations in width and height over the whole build-up process were detected and customized build-up strategies for the 3D sequences were designed. The results show the possibility of a near net shape repair by using different track geometries with laser metal deposition. T2 - LANE - 9 International Conference on Photonic Technologies CY - Fürth, Germany DA - 19.09.2016 KW - Laser metal deposition KW - Inconel 718 KW - Additive manufacturing KW - Maintenance KW - Repair and overhaul PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-376723 UR - http://ac.els-cdn.com/S1875389216301857/1-s2.0-S1875389216301857-main.pdf?_tid=ed1d75de-84a2-11e6-af94-00000aab0f6c&acdnat=1474974777_4917d753cb3d316c4b000ba0760778b5 DO - https://doi.org/10.1016/j.phpro.2016.08.078 SN - 1875-3892 VL - 83 SP - 761 EP - 768 PB - Elservier AN - OPUS4-37672 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Winkelmann, Aimo A1 - Nolze, Gert A1 - Voss, M. A1 - Salvat-Pujol, F. A1 - Werner, W. S. M. T1 - Physics-based simulation models for EBSD: advances and challenges T2 - IOP Conf. Series: Materials Science and Engineering N2 - EBSD has evolved into an effective tool for microstructure investigations in the scanning electron microscope. The purpose of this contribution is to give an overview of various simulation approaches for EBSD Kikuchi patterns and to discuss some of the underlying physical mechanisms. T2 - EMAS 2015 - 14th European Workshop on MODERN DEVELOPMENTS AND APPLICATIONS IN MICROBEAM ANALYSIS CY - Portoroz, Slovenia DA - 03.05.2015 KW - Electron backscatter diffraction KW - Simulation KW - Dynamical theory KW - Kinematic theory PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-377469 DO - https://doi.org/10.1088/1757-899X/109/1/012018 VL - 109 SP - 012018-1 EP - 012018-13 AN - OPUS4-37746 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bachmann, Marcel A1 - Gumenyuk, Andrey A1 - Rethmeier, Michael T1 - Welding with high-power lasers: trends and developments T2 - Physics Procedia - 9th International Conference on Photonic Technologies - LANE 2016 N2 - High-power laser beam welding became new stimuli within the last 10 years due to the availability of a new generation of high brightness multi kilowatt solid state lasers. In the welding research new approaches have been developed to establish reliable and praxis oriented welding processes meeting the demands of modern industrial applications during this time. The paper focuses on some of the current scientific and technological aspects in this research field like hybrid laser arc welding, simulation techniques, utilization of electromagnetic fields or reduced pressure environment for laser beam welding processes, which contributed to the further development of this technology or will play a crucial role in its further industrial implementation. T2 - 9th International Conference on Photonic Technologies - LANE 2016 CY - Fürth, Germany DA - 19.09.2016 KW - High-power Laserbeam Welding KW - Electromagnetic Force KW - Vacuum KW - Simulation PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-377280 DO - https://doi.org/10.1016/j.phpro.2016.08.003 VL - 83 SP - 15 EP - 25 PB - Elsevier B.V. CY - Berlin, Germany AN - OPUS4-37728 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Schröpfer, Dirk A1 - Flohr, Kerstin A1 - Kromm, Arne A1 - Kannengießer, Thomas ED - Holden, T.M. ED - Muránsky, O. ED - Edwards, L. T1 - Multi-axial Analyses of Welding Stresses in High-Strength Steel Welds T2 - Materials Research Proceedings N2 - Today’s efforts for lightweight design result in a growing application of high-strength structural steels from 960 MPa. In welded structures of these steels increased demands regarding component safety and a high elastic ratio should be considered. Hence, the prevention of an evolution of high weld-induced tensile residual stresses is required. Recent studies showed that component related restraint conditions of welds are able to elevate welding induced stresses to critical values, depending on material characteristics, the welding process and parameters. This work involves multi-axial welding loads as a consequence of the superposition of local residual stresses, global reaction stresses and moments, varying the welding parameters under different restraint conditions. The global welding loads are measured via GMA-weld tests in a special testing facility and via a DIC(Digital Image Correlation)-system in a slot weld. Local transverse residual stresses were analysed by means of X-ray diffraction. The application of a less amount of weld runs due to a modified welding parameters and welds seam configurations revealed as a beneficial approach to reduce welding loads in high-strength steels. T2 - 10th International Conference on Residual Stresses CY - Sydney, Australia DA - 04.07.2016 KW - High-Strength Steel KW - Welding KW - Reaction Stress KW - X-Ray Diffraction PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-390453 SN - 978-1-9452-9116-6 DO - https://doi.org/10.21741/9781945291173-35 SN - 2474-395X VL - 2 SP - 205 EP - 210 PB - Materials Research Forum LLC. CY - Millersville PA, USA AN - OPUS4-39045 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Dixneit, Jonny A1 - Kromm, Arne A1 - Boin, M. A1 - Kannengießer, Thomas A1 - Gibmeier, J. ED - Olden, T.-M. ED - Muransky, O. Muransky ED - Edwards, L. T1 - Influence of heat control on residual stresses in low transformation temperature (LTT) large scale welds T2 - Residual Stresses 2016: ICRS-10 N2 - The current paper presents residual stress analyses of large scale LTT (Low Transformation Temperature) welds. LTT filler materials are specially designed for residual stress engineering by means of an adjusted martensite phase transformation. Controlling the level of mostly detrimental residual stresses already during the welding process would be highly attractive as time and cost consuming post processing may be prevented. In large scale welds the residual stress state is influenced by the heat control (e.g. interpass temperature) during welding. Therefore, welding residual stresses are studied here putting the focus on the influence of welding process parameters while joining heavy steel sections with a thickness of 25 mm. The residual stress state was determined at the top surface using X-ray diffraction as well as in the bulk by neutron diffraction. The results show that control of the interpass temperature is vital for the residual stresses present in the joints. This accounts for the top surface but is most pronounced for the bulk of the welds. While high interpass temperatures are appropriate to induce compressive residual stresses in the weld metal, low interpass temperatures favor unwanted tensile residual stresses instead. T2 - ICRS 2016 - 10th International Conference on Residual Stresses CY - Sydney, Australia DA - 03.07.2016 KW - LTT KW - Welding residual stress KW - Phase transformation KW - Interpass temperature PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-389628 SN - 978-1-94529117-3 SN - 978-1-94529116-6 DO - https://doi.org/10.21741/9781945291173-38 SN - 2474-395X VL - 2 SP - 223 EP - 228 PB - Materials Research Forum LLC CY - Millersville (PA), USA AN - OPUS4-38962 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Kromm, Arne A1 - Schasse, R. A1 - Xu, Ping A1 - Mente, Tobias A1 - Kannengießer, Thomas ED - Olden, T.-M. ED - Muransky, O. ED - Edwards, L. T1 - Influence of weld repair by gouging on the residual stresses in high strength steels T2 - Residual Stresses 2016: ICRS-10 N2 - Carbon arc-air gouging is a common technology when repairing defects in welded structures. Often this technique is applied in repeated cycles even on the same location of the joint. Due to the multiple heat input by gouging and subsequent re-welding, the residual stresses are strongly influenced. This can become crucial when microstructure and mechanical properties are adversely affected by multiple weld reparations. Knowledge about the relation of gouging and residual stresses is scarce but important when high strength steels, which are sensitive to residual stresses, are processed. The present study shows the effect of repair welding on a high strength steel structural element. The weld and the heat affected zone were subjected to multiple thermal cycles by gouging and subsequent repair welding. The residual stresses were determined by X-ray diffraction at different positions along the joint. The results showed that the residual stress level has increased by the repair cycles. This is most pronounced for the heat affected zone. Adapted welding procedures may prevent detrimental residual stress distributions. T2 - ICRS 2016 - 10th International Conference on Residual Stresses CY - Sydney, Australia DA - 03.07.2016 KW - Repair welding KW - Weld residual stress KW - Carbon arc-air gouging PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-389242 SN - 978-1-94529117-6 SN - 978-1-94529117-3 DO - https://doi.org/10.21741/9781945291173-29 SN - 2474-395X VL - 2 SP - 169 EP - 174 PB - Materials Research Forum LLC CY - Millersville, PA, USA AN - OPUS4-38924 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Launert, B. A1 - Rhode, Michael A1 - Kromm, Arne A1 - Pasternak, H. A1 - Kannengießer, Thomas ED - Olden, T.-M. ED - Muransky, O. ED - Edwards, L. T1 - Residual stress influence on the flexural buckling of welded I-girders T2 - Residual Stresses 2016: ICRS-10 N2 - The nonlinear analysis became a common tool to precisely assess the load-bearing behavior of steel beam and column members. The failure level is significantly influenced by different types of imperfections, among geometric also structural imperfections (residual stresses). Here are still gaps in the knowledge. Nowadays, 3-D welding simulation developed to a level where it could provide reliable estimation of weld-induced distortion and residual stresses. Nevertheless, modelling and computational effort are still in a less practicable range. In this study a simplified procedure to implement residual welding stresses in continuous large scale members is proposed and the influence on the ultimate limit state of slender members in compression is evaluated for two common structural steel grades. The results showed significant improvements in the utilization of load bearing capacity compared with simplified design methods. The comparatively general approach in this study offers potential for future optimization. T2 - ICRS 2016 - 10th International Conference on Residual Stresses CY - Sydney, Australia DA - 03.07.2016 KW - Stability Design KW - Finit Element Method KW - 2-D Welding Simulation KW - Inherent Strain KW - Plasticity-based Analysis PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-389210 SN - 978-1-94529117-3 SN - 978-1-94529117-6 DO - https://doi.org/10.21741/9781945291173-19 SN - 2474-395X VL - 2 SP - 109 EP - 114 PB - Materials Research Forum LLC CY - Millersville (PA), USA AN - OPUS4-38921 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Hüllmann, Dino A1 - Kohlhoff, Harald A1 - Neumann, Patrick P. ED - Bársony, I. ED - Zolnai, Z. ED - Battistig, G. T1 - Embedded control of a PMSM servo drive without current measurements T2 - Proceedings of the 30th anniversary Eurosensors Conference – Eurosensors 2016 N2 - A permanent-magnet synchronous motor (PMSM) servo drive for lightweight robotic platforms that have a high torque demand at low rotational speeds has been developed. First, a current-independent torque controller is derived and cascaded with a speed and position controller, while merely an encoder is used as a sensor device in combination with a speed estimator. Finally, the speed estimator output is compared to gyroscope measurements and the overall functioning is verified on a real system. T2 - 30th Eurosensors Conference - Eurosensors 2016 CY - Budapest, Hungary DA - 04.09.2016 KW - BLDC KW - PMSM KW - Motor control KW - Servo drive KW - Optical incremental encoder PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-388973 DO - https://doi.org/10.1016/j.proeng.2016.11.487 SN - 1877-7058 VL - 168 SP - 1671 EP - 1675 PB - Elsevier B.V. CY - Amsterdam, Netherlands AN - OPUS4-38897 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -