低合金钢与不锈钢AA-TIG自熔焊接头组织及力学性能  

Microstructure and mechanical properties of AA-TIG autogenous welded joints of low alloy steel and stainless steel

作　　者：张建晓 赵金龙 王纯 樊丁[1] 黄勇[1] Zhang Jianxiao;Zhao Jinlong;Wang Chun;Fan Ding;Huang Yong(Lanzhou University of Science and Technology,Lanzhou 730050,China;Lanzhou Lanshi Heavy Equipment Co.,Ltd.,Lanzhou 730314,China;Harbin Well Welding Co.,Ltd.,Harbin 150028,China)

机构地区：[1]兰州理工大学,兰州730050 [2]兰州兰石重型装备股份有限公司,兰州730314 [3]哈尔滨威尔焊接有限责任公司,哈尔滨150028

出　　处：《焊接》2020年第4期1-5,15,61,共7页Welding & Joining

基　　金：国家自然科学基金(51205179,51265029)。

摘　　要：采用电弧辅助活性TIG焊(AA-TIG)对8 mm厚的SA537 CL2低合金钢和S32168不锈钢进行不开坡口对接自熔焊试验,实现了高效的单面焊双面成形,对接头显微组织及力学性能进行了分析。结果表明,SA537 CL2热影响区产生了颗粒状的贝氏体,SA537 CL2侧熔合区组织为相互交错的颗粒状贝氏体与板条马氏体,焊缝的显微组织主要为板条马氏体和残余奥氏体,S32168热影响区组织仍为奥氏体,晶粒略有长大;接头硬度高于母材,在SA537 CL2与焊缝的熔合界面处碳积聚形成高硬度的增碳层;室温拉伸断裂于SA537 CL2侧熔合区,为韧性断裂;-20℃的焊缝冲击吸收能量可以达到SA537 CL2母材水平;接头面弯、背弯检验合格。The arc-assisted active TIG welding(AA-TIG)was used to weld 8 mm thick SA537 CL2 low alloy steel and S32168 stainless steel without bevel butt,which realized efficient one-side welding with back.Microstructure and mechanical properties of the joint were analyzed.The results showed that SA537 CL2 heat affected zone produced granular bainite,microstructure of SA537 CL2 fusion zone was interlaced granular bainite and lath martensite.Microstructure of the weld was mainly lath austenitic and residual austenite.Microstructure of S32168 heat affected zone was still austenite,but the grains grew slightly.Hardness of the joint was higher than that of the base metal,and carbon was accumulated at the fusion interface of SA537 CL2 and the weld to form a high hardness carbon-reinforced layer.Tensile fracture was ductile fracture at room temperature in the fusion zone of SA537 CL2 side.Impact value of the weld at-20℃reached the level of SA537 CL2 base material.Surface and back bend inspection of the joint were qualified.

关 键 词：异种钢焊接 AA-TIG焊 显微组织 力学性能 

分 类 号：TG442[金属学及工艺—焊接]