Q450NQR1/Q355GNHD异种钢焊接接头的力学性能及腐蚀行为  

Mechanical Properties and Corrosion Behavior of Q450NQR1/Q355GNHD Dissimilar Steel Welded Joints

作　　者：刘志盛 刘龙玺 张成功 刘瑞琳 朱宗涛[2] LIU Zhisheng;LIU Longxi;ZHANG Chenggong;LIU Ruilin;ZHU Zongtao(CRRC Qingdao Sifang Co.,Ltd.,Qingdao 266111,China;College of Materials Science and Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]中车青岛四方机车车辆股份有限公司,山东青岛266111 [2]西南交通大学材料科学与工程学院,四川成都610031

出　　处：《热加工工艺》2022年第23期63-67,共5页Hot Working Technology

摘　　要：采用MAG自动焊和CHW-55CNH焊丝,对6mm厚的Q450NQR1/Q355GNHD异种钢板进行了焊接,分析了焊接接头不同区域的微观组织,测试了接头的硬度和拉伸性能,通过电化学腐蚀和盐雾腐蚀试验,研究了接头不同区域的腐蚀性能。结果表明:Q450NQR1/Q355GNHD异种钢焊缝成形良好,无明显的咬边、未焊透以及未熔合等缺陷。焊缝处的硬度较两侧母材的高,接头的抗拉强度介于两种母材之间,拉伸断裂在Q355GNHD母材处,为韧性断裂。中性盐雾腐蚀结果表明,接头和两侧母材均腐蚀严重,表面积聚了较厚的腐蚀产物,电偶腐蚀效果不明显。接头焊缝区的耐蚀性低于母材的,热影响区的耐蚀性能与母材的相当。The 6 mm thick Q450NQR1/Q355GNHD dissimilar steel plates were welded by MAG automatic welding and CHW-55CNH welding wire. The microstructure of different areas of the welded joint was analyzed, and the hardness and tensile properties of the joint were tested. The corrosion properties of different areas of the joint were studied by electrochemical corrosion and salt spray corrosion tests. The results show that the weld of Q450NQR1/Q355GNHD dissimilar steel is well formed without obvious defects such as undercut, incomplete penetration and incomplete fusion. The hardness of the weld is higher than that of the base metals, the tensile strength of the joint is between that of the two base metals, the tensile fracture is at the base metal of Q355GNHD, which is ductile fracture. The neutral salt spray corrosion results show that the joint and the base metals at both sides are seriously corroded, and thick corrosion products are accumulated on the surface area, and the galvanic corrosion effect is not obvious. The corrosion resistance of the weld zone of the joint is lower than that of the base metal, and the corrosion resistance of the heat affected zone is equivalent to that of the base metals.

关 键 词：异种钢 MAG焊 力学性能 盐雾腐蚀 极化曲线 

分 类 号：TG444.7[金属学及工艺—焊接]