Q345B低碳钢/20Mn23Al无磁钢异种钢焊接接头的组织及性能  

Microstructure and Property of Dissimilar Steel Welded Joint of Q345B Low Carbon Steel and 20Mn23Al Non-magnetic Steel

作　　者：张敏[1] 杜明科 张云龙 王刚[1] 朱子越 ZHANG Min;DU Mingke;ZHANG Yunlong;WANG Gang;ZHU Ziyue(School of Materials Science and Engineering,Xi'an University of Technology,Xi*an 710048,China)

机构地区：[1]西安理工大学材料科学与工程学院,西安710048

出　　处：《机械工程材料》2021年第8期66-71,共6页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(51274162);陕西省教育厅服务地方专项计划项目(16JF021);陕西省教育厅重点实验室科研计划项目(15JS082);西安市科技计划项目(201805037YD15CG21(16))。

摘　　要：采用E316LT0-1不锈钢焊丝对Q345B低碳钢和20Mn23Al无磁钢进行熔化极气体保护焊,研究了焊接接头的显微组织和力学性能。结果表明:接头填充焊层组织主要为骨骼状δ-铁素体和奥氏体,打底焊层组织主要为树枝状铁素体和奥氏体;Q345B钢侧过热粗晶区组织为贝氏体和魏氏体,相变重结晶区组织为珠光体和铁素体,20Mn23Al钢侧热影响区组织为孪晶奥氏体和少量铁素体;母材和焊缝中的合金元素发生互扩散,Q345B钢和20Mn23Al钢侧扩散层厚度分别约为15,25μm;接头拉伸性能优于Q345B钢但略差于20Mn23Al钢,接头焊缝区硬度最大,热影响区次之。Q345 B low carbon steel and 20 Mn23 Al non-magnetic steel were welded by gas metal arc welding with E316 LT0-1 stainless steel welding wire.The microstructure and mechanical properties of the welded joint were studied.The results show that the microstructure of the filling weld layer consisted of skeletalδferrite and austenite,and that of the backing weld layer was composed of dendritic ferrite and austenite.The microstructure of the overheated coarse-grained zone on the Q345 B steel side consisted of bainite and Widmanstaten structure,and that of the phase transformation recrystallization zone consisted of pearlite and ferrite.The heat-affected zone on the 20 Mn23 Al steel side had a microstrucrture of twin austenite and a small amount of ferrite.The interdiffusion of alloying elements in the base metals and weld occured,and the diffusion layer thicknesses on the Q345 B steel side and 20 Mn23 Al steel side were about 15,25μm,respectively.The tensile property of the joint was better than that of the Q345 B steel while worse than that of the 20 Mn23 Al steel.The weld of the joint had the largest hardness,followed by the heat-affected zone.

关 键 词：异种钢焊接 元素扩散 显微组织 力学性能 

分 类 号：TG407[金属学及工艺—焊接]