高氮不锈钢与675高强钢焊接接头微观组织与力学性能  

Microstructure and mechanical properties of welded joint between high nitrogen stainless steel and 675 high strength steel

作　　者：周杰[1] 张明渝 李志洋 张建[1] 范霁康 王克鸿[1] Zhou Jie;Zhang Mingyu;Li Zhiyang;Zhang Jian;Fan Jikang;Wang Kehong(Nanjing University of Science and Technology,Key Laboratory of Controlled Arc Intelligent Additive Manufacturing Technology,Nanjing 210094,China;Kunshan Huaheng Welding Co.,Ltd.,Kunshan 215300,Jiangsu,China)

机构地区：[1]南京理工大学,受控电弧智能增材技术工业和信息化部重点实验室,南京210094 [2]昆山华恒焊接股份有限公司,江苏昆山215300

出　　处：《焊接》2022年第2期6-10,共5页Welding & Joining

基　　金：国防基础科研项目(JCKY208A001)。

摘　　要：根据低强匹配原则,采用ER307Mo不锈钢焊丝对13.5 mm厚高氮不锈钢和675高强钢进行了脉冲MIG焊接试验。结果表明,当焊接速度为5 mm/s、送丝速度为5.5~6.0 m/min、焊接电流为155~166 A、电弧电压为19.6~20.3 V时,可以得到成形良好、性能较佳的焊接接头。焊缝组织主要由奥氏体与铁素体组成,其中铁素体从奥氏体晶界中析出;高氮不锈钢侧热影响区组织主要为块状奥氏体,而675高强钢侧热影响区主要为马氏体组织。焊接接头抗拉强度约为730 MPa,达到高氮不锈钢母材强度的71%,接头的断裂形式为韧性断裂,未发现明显的解理断裂特征。According to the principle of“low strength matching”,pulse MIG welding experiments of high nitrogen stainless steel and 675 high strength steel with 13.5 mm thickness were carried out with ER307Mo stainless steel wire.The results showed that the welded joint with good formation and better performance could be obtained when the welding speed was 5 mm/s,the wire feeding speed was 5.5~6.0 m/min,the welding current was 155~166 A,and the arc voltage was 19.6~20.3 V.Microstructure of the weld was mainly composed of austenite and ferrite,of which ferrite precipitated from the austenite grain boundary.The lateral heat affected zone of high nitrogen stainless steel was dominated by massive austenite,while that of 675 high strength steel was dominated by martensite.The tensile strength of welded joint was about 730MPa,which was 71%of the strength of high nitrogen stainless steel base material.The fracture form of welded joint was ductile fracture,and no obvious cleavage fracture was found.

关 键 词：高氮不锈钢 675高强钢 脉冲MIG 微观组织 力学性能 

分 类 号：TG444[金属学及工艺—焊接]