焊接速度对DP590双相钢板激光焊接接头组织和性能的影响  

Effects of Welding Speed on Microstructure and Property of Laser Welded Joint of DP590 Dural Phase Steel Sheet

作　　者：涂英明 景财年[1] 范吉超 倪晓梅[1] 刘鹏[1] 李怀学[2] 

机构地区：[1]山东建筑大学材料科学与工程学院,济南250101 [2]北京航空制造工程研究所,北京100084

出　　处：《机械工程材料》2016年第12期69-72,77,共5页Materials For Mechanical Engineering

基　　金：国家自然科学基金资助项目(51305240);山东省科技发展计划项目(2013GGX10306)

摘　　要：利用光学显微镜、拉伸试验机及硬度计等研究了焊接速度对激光焊接DP590双相钢板接头组织和性能的影响。结果表明:该接头组织主要由马氏体和贝氏体组成,随着焊接速度的增加,焊缝中马氏体板条变得细短且体积分数增大,热影响区组织逐渐细化;接头表面硬度以焊缝为中心呈对称分布,且从焊缝至母材整体呈下降趋势,焊缝区的显微硬度较高,约为母材的1.6倍;接头试样拉伸后均在母材区发生断裂,不同速度焊接后DP590钢板接头的抗拉强度均不低于母材的,伸长率与母材的相当,焊接速度对接头拉伸性能的影响很小。The effects of welding speed on the microstructure and property of the laser welded joints of DP590 dual phase steel sheet were studied by optical microscope,tensile testing machine and hardness tester.The results show that the microstructure of the joint consisted of martensite and banitite.With the increase of the welding speed,the martensite lath in the weld became thin and short and the volume fraction increased,while the microstructure of the heat affected zone was refined gradually.The surface hardness of the joint showed a symmetric distribution on both sides of the weld center and decreased from the weld to the base material.The hardness of the weld were relatively high,which was 1.6 times that of the base material.After tensile test,the joint samples all fractured in the base material zone.The tensile strength of the DP590 steel sheet joints welded at different welding speeds was no lower than and the elongation was equivalent to those of the base material.The welding speed had little effect on the tensile properties of the joint.

关 键 词：双相钢 焊接速度 激光焊接 拉伸性能 

分 类 号：TG456.7[金属学及工艺—焊接]