低成本TC4钛合金单丝MIG焊工艺与性能研究  

Single wire MIG welding technology and properties of low-cost TC4 titanium alloy

作　　者：张龙 陈东高[1] 张迎迎[1] 马良超 王大锋 戴宇[1] 郭庆虎 ZHANG Long;CHEN Donggao;ZHANG Yingying;MA Liangchao;WANG Dafeng;DAI Yu;GUO Qinghu(Ningbo Branch of Chinese Academy of Ordnance Science,Ningbo 315103,China)

机构地区：[1]中国兵器科学研究院宁波分院,浙江宁波315103

出　　处：《兵器材料科学与工程》2021年第1期93-97,共5页Ordnance Material Science and Engineering

摘　　要：针对中厚度低成本TC4钛合金板,用单丝MIG工艺研究有无保护装置、不同层间温度、有无焊接摆动等参数对接头质量的影响,用拉伸、显微硬度、金相、扫描等试验测量和分析接头性能与组织。结果表明:单丝MIG焊显著提高钛合金焊接效率,无保护装置的接头内部有裂纹和气孔,层间温度低的接头抗拉强度和韧性更好,摆动与不摆动拉伸性能相当。真空电子束冷床熔炼的母材为片层组织,热影响区是残留α相和α′马氏体相组成的混合组织,焊缝区为α′马氏体相。焊缝区显微硬度最高为349HV,热影响区比焊缝区低24HV,母材比焊缝区低44HV。Aiming at low-cost medium thickness TC4 titanium alloy,the influences of protective device,interlayer temperature and welding swing on the quality of welded joint were studied by single wire MIG process.The properties and microstructure of joints were measured and analyzed by tensile test,microhardness test,metallographic test and scanning test.The results show that the single wire MIG welding can significantly improve the welding efficiency of titanium alloy.There are cracks and porosity defects in the joints without protection device.The tensile strength and toughness of joints with low interlayer temperature are better,and the tensile properties of swing and non swing are similar.The base metal of vacuum electron beam furnace melting is lamellar structure,the HAZ is a mixture of residualαphase andα′martensite phase,and the weld zone isα′martensite.The highest microhardness of weld zone is 349 HV,while the HAZ is 24 HV lower than that of the weld zone,and the base metal of low-cost titanium alloy is 44 HV lower than that of the weld zone.

关 键 词：TC4钛合金 单丝MIG 显微组织 显微硬度 

分 类 号：TG444.74[金属学及工艺—焊接]