TY - CONF A1 - Xu, Ping T1 - Determination of fatige crack initiation and crack propagation on spot welded joints with highprecision thermometry T2 - 57th Annual Assembly of International Institute of Welding (IIW), Com. III T2 - 57th Annual Assembly of International Institute of Welding (IIW), Com. III CY - Osaka, Japan DA - 2004-07-15 PY - 2004 AN - OPUS4-4935 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Xu, Ping A1 - Weber, Gert A1 - Böllinghaus, Thomas A1 - Krause, Hans-Joachim T1 - Determination of Relevant Fatigue Charcteristics for Joined Thin Sheet Metal Structures on Suitable Specimens with Appropriate Test Methods T2 - The 8th International Factigue Congress "FATIGUE 2002" T2 - The 8th International Factigue Congress "FATIGUE 2002" CY - Stockholm, Sweden DA - 2002-06-01 PY - 2002 AN - OPUS4-7170 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Xu, Ping A1 - Weber, Gert A1 - Tischlinger, Wolfgang T1 - Extended Weldability Lobes in Resistance Spot Welding T2 - 56th Annual Assembly of IIW T2 - 56th Annual Assembly of IIW CY - Bucharest, Romania DA - 2003-07-06 PY - 2003 AN - OPUS4-4025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Xu, Ping T1 - Fatigue Testing for Spot Welds - Problems, Solutions and New Development T2 - SEA World Congress T2 - SEA World Congress CY - Detroit, MI, USA DA - 2003-03-03 PY - 2003 AN - OPUS4-4023 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Xu, Ping T1 - Simple but Effective - a Mechanical Methode to Improve the Fatigue Behaviour of Spot Welded High-Strength Steels T2 - The 3rd International Seminar on Advances in Resistance Welding N2 - Substantial improvement in the fatigue strength of spot welded high-strength steels has been achieved with the help of a mechanical method, i. e. preloading. Fatigue tests of preloaded tensile shear specimens made from the material H280LA have revealed that their S/N-curves, compared to those of non-preloaded specimens, are not only located at elevated positions, but have flatter slope, too. Low cycle fatigue tests of the triple-spot weld tensile shear specimens examined yielded an increase in fatigue strength of around 50 %. Due to preloading, the notch zones in the spot welded area undergo plastic deformation as a result of high notch stresses. After specimen unloading, compressive stresses arise in this area involving a beneficial specimen behaviour under the load imposed in subsequent fatigue testing, thus causing delayed crack initiation in the spot weld area. T2 - The 3rd International Seminar on Advances in Resistance Welding CY - Berlin, Germany DA - 2004-11-16 PY - 2004 AN - OPUS4-4750 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -