Q235/304异种钢激光焊接接头组织及力学性能研究  

Study on Microstructure and Mechanical Properties of Laser Welded Joint of Q235/304 Dissimilar Steel

作　　者：徐育烺 李敬勇[1] 石铭霄[1] 钱鹏 彭磊 Xu Yulang;Li Jingyong;Shi Mingxiao;Qian Peng;PengLei(College of Material Science and Engineering,Jiangsu Unversity of Science and Technology,Zhenjiang,Jiangsu 212003,China)

机构地区：[1]江苏科技大学材料科学与工程学院,江苏镇江212003

出　　处：《应用激光》2022年第4期21-28,共8页Applied Laser

摘　　要：采用激光自熔焊接对Q235普通碳素钢和304奥氏体不锈钢进行异种钢焊接试验,研究不同焊接工艺参数对异种钢焊接接头的组织和力学性能的影响。试验结果表明,激光束能量密度高度集中,可以得到热影响区狭窄的高质量焊缝。根据直读光谱获取的元素含量,通过舍夫勒相图推测焊缝区域组织为马氏体组织,利用金相显微镜以及扫描电镜分析仪器验证焊缝主要由板条马氏体组织组成。显微硬度试验研究表明,焊缝区域硬度高于两侧母材。在热输入充足、焊接接头完全熔透的条件下,拉伸断裂发生在母材Q235钢一侧,说明焊接接头强度高于碳钢母材;焊接热输入不足时,会使得焊缝存在未熔合缺陷,甚至产生气孔,焊接接头拉伸断裂位置发生在焊缝中心。Laser self-fusion welding was used to weld Q235 ordinary carbon steel and 304 austenitic stainless-steel dissimilar steel, and the effects of different welding parameters on microstructure and mechanical properties of dissimilar steel welded joints were studied. Experimental results show that high quality welding seam and small heat affected zone can be obtained due to the high concentration of laser energy density. According to the element content obtained from the direct reading spectrum, and refer to the Schaeffler diagram, it can be inferred that the microstructure of the weld area is composed of martensite. Metallographic microscope and scanning electron microscope were used to verify that the weld seam is mainly composed of lath martensite. The microhardness tests show that the microhardness of weld zone is higher than that of base metal on both sides. Under the condition of sufficient heat input and complete penetration of welded joint, tensile fracture occurs on the side of Q235 steel of base metal, which indicates that the strength of welded joint is higher than that of base metal if the welding heat input is insufficient, there will be incomplete fusion defects and even air holes in the weld joint, and the tensile fracture of welded joint occurred in the weld zone.

关 键 词：异种钢 激光焊 微观组织 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]