TY - CONF A1 - Baer, Wolfram T1 - Validation of a low blow specimen technique for R-curve determination using a drop tower N2 - The effect of bouncing strikes on crack extension in low blow tests has been investigated. • Crack propagation sensor signals, force-displacement records and loading level have been analyzed. • Additional crack extension in the specimen due to bouncing strikes of the hammer is not to be expected. It can be seen as a major experimental advantage that the striker does not have to be catched after the low blow test. • This has to be proved for the given conditions of test setup, material and loading. T2 - ECF21 - European Conference on Fracture CY - Catania, Italy DA - 20.06.2016 KW - Testing method KW - Dynamic fracture mechanics KW - Material characteristics KW - Low blow PY - 2016 AN - OPUS4-38197 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Frei, J. A1 - Biegler, M. A1 - Rethmeier, Michael T1 - Resistance spot welding under external load for evaluation of LME susceptibility of zinc coated advanced high strength steel sheets N2 - Some zinc coated advanced high strength steels (AHSS), under certain manufacturing conditions, are known to be prone to liquid metal embrittlement (LME) during resistance spot welding. LME is an undesired phenomenon, which can cause both surface and internal cracks in a spot weld, potentially influencing its strength. An effort is made to understand influencing factors of LME better, and evaluate geometry-material combinations regarding their LME susceptibility. Manufacturers benefit from such knowledge because it improves the processing security of the materials. The experimental procedure of welding under external load is performed with samples of multiple AHSS classes with strengths up to 1200 MPa, including dual phase, complex phase and TRIP steels. This way, externally applied tensile load values are determined, which cause liquid metal embrittlement in the samples to occur. In the future, finite element simulation of this procedure gives access to in-situ stress and strain values present during LME formation. The visualization improves the process understanding, while a quantification of local stresses and strains allows an assessment of specific welded geometries. T2 - ESDAD 2019 CY - Dusseldorf, Germany DA - 24.06.2019 KW - RSW KW - LME KW - Advanced high strength steel KW - Testing method KW - Zinc coated steel PY - 2019 AN - OPUS4-49079 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -