Analysis of martensite transformation behaviour in welded joint using low transformation temperature welding wire

作者：Yamamoto J^*; Hiraoka K; Mochizuki M

来源：Science and Technology of Welding and Joining, 2010, 15(2): 104-110.

DOI：10.1179/136217109X12568132624442

• Martensite transformation
• Austenite
• Transformation expansion
• Transformation superplasticity
• Transformation induced plasticity

Low transformation temperature welding (LTTW) wire has been found to improve the fatigue strength in welded joints. In the present study, the temperature dependence of the mechanical properties in a dual phase microstructure of austenite and martensite was estimated using the properties of full austenite and full martensite in numerical analyses. A welding method effective for residual stress reduction and fatigue strength improvement was shown by applying a calculation method under transformation superplasticity and transformation induced plasticity in high strength steel welded joints. With this method, the influence of the welding pass sequence on the residual stress distribution and fatigue strength was examined in a boxing fillet welded joint using LTTW. The transformation tensile residual stress in the weld toe was decreased by sectioned welding, and the fatigue limit by sectioned welding with LTTW improved in comparison with the fatigue limit of a joint welded with conventional wire in the same process.

• 出版日期2010-2