Q345B大厚板双面双弧焊接头组织与力学性能  

Microstructures and Mechanical Properties of Q345B Steel Weld Joint Using Double-sided Arc Welding

作　　者：高桂丽[1] 缪神 蔡春波 张华军 GAO Gui-li;MIAO Shen;CAI Chun-bo;ZHANG Hua-jun(School of Material Science and Engineering,Harbin University of Science and Technology,Harbin 150040,China;Shanghai Zhenhua Port Machinery Co.,Ltd,Shanghai 200125,China)

机构地区：[1]哈尔滨理工大学材料科学与工程学院,黑龙江哈尔滨150040 [2]上海振华重工(集团)股份有限公司,上海200125

出　　处：《哈尔滨理工大学学报》2018年第4期113-117,共5页Journal of Harbin University of Science and Technology

基　　金：黑龙江省教育厅科学技术研究项目(12531042)

摘　　要：针对Q345B大厚板高强钢接头在机器人双面双弧焊中易出现焊不透、撞枪的问题,采用根部无预留间隙的焊接方法,通过增大焊接线能量、减小弧间距实现根部全熔透。依据《美国钢结构焊接规范》标准对接头进行力学性能试验和显微组织分析,结果表明:根部打底前焊道组织为针状铁素体和贝氏体,打底后焊道和填充焊组织为针状铁素体和少量的先共析铁素体;熔合区组织为针状铁素体和板条马氏体,粗晶区为板条束更粗大的板条马氏体。焊接接头平均抗拉强度达到536.47 MPa,焊缝强度高于母材。接头出现局部硬化,硬度最高值为281 HV,符合标准的要求。To solve the problem of incomplete penetration and the welding torch hitting the plate during the welding process of Q345B large thick plate by using robot double-sided arc welding,the method of using no reserved-clearance root was proposed.The good forming weld joint was obtained by increasing the welding line energy and reducing the arc distance.The microstructure and mechanical properties of the welding joint were investigated according to the AWS D1.1.The results show that the first weld pass of root consists of acicular ferrite and bainite,and the second weld pass of root and filling pass consist of acicular ferrite and few of proeutectoid ferrite,and the microstructure of fusion region consists of acicular ferrite and lath martensite,and the coarse grain region consists of larger lath martensite.The average tensile strength of Welding joint reaches 536.47 MPa,and the tensile strength of welding is larger than fusion.Impact property of welding joint is good,and the highest hardness reaches 281 HV.

关 键 词：Q345B大厚板 双面双弧焊 无预留间隙 机器人 

分 类 号：TG444[金属学及工艺—焊接]