激光焊接线能量对TRIP钢焊接接头组织性能的影响

Effect of Linear Energy of Laser Welding on Microstructure and Properties of TRIP Steel Welded Joints

对不同焊接线能量下的TRIP钢板激光焊接接头显微组织进行观察。结果表明:焊缝区主要由马氏体组成,马氏体有一定的择优取向,热影响区主要由贝氏体和铁素体组成;随着线能量的增加,焊缝区马氏体变粗大,残余奥氏体含量减少,热影响区组织从下贝氏体转变为上贝氏体;焊缝和热影响区的宽度增加,接头抗拉强度减小。

The microstructure of laser welded joints of TRIP steel plates with different heat input was observed. The results show that the weld zone is mainly composed of martensite, the martensite has a preferred orientation, the HAZ microstucture is mainly composed of bainite and ferrite. With the increase of heat input, the size of martensite in weld zone increases and the retained austenite content decreases, the HAZ microstucture changes from lower bainite to upper bainite, the widths of weld and HAZ increase, and the tensile strength of the joint decreases.