TY - JOUR A1 - Kannengießer, Thomas A1 - Kromm, Arne T1 - Characterising phase transformations of different LTT alloys and their effect on residual stresses and cold cracking T2 - Welding in the World N2 - Novel martensitic filler materials with specially adjusted martensite start temperatures (Ms) can counteract the cooling specific shrinkage due to expansion effects of the weld metal associated with phase transformations. That can be exploited to create compressive residual stresses in the weld and adjacent areas, i.e. beneficial for increasing fatigue strength. The Ms temperature is shifted via the chemical composition, mainly by the alloying elements nickel and chromium, resulting as well in different retained austenite contents. Investigations were made using different Low Transformation Temperature (LTT) alloys with varying nickel content. The resulting phase transformation temperatures were – for the first time – detected using high energy synchrotron diffraction and Single Sensor Differential Thermal Analysis (SS-DTA). Compared to angle dispersive diffraction, energy dispersive diffraction offers the possibility to measure residual stresses of the martensite and austenite phase parallel fast in one experiment up to depths of 100 µm. The residual stresses show significant distributions dependent on Ms temperature. The effect on the cold cracking behaviour of these alloys was investigated using the Tekken test. Results show that cold cracking can be avoided when appropriate contents of retained austenite are existent. PB - International Institute of Welding CY - France KW - Austenite KW - Cold cracking KW - Martensite KW - Low themperature KW - Transformation PY - 2011 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/38978 AN - OPUS4-38978 SN - 0043-2288 VL - 55 IS - 3 SP - 48 EP - 56 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany