Improving microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys friction stir lap joints via TIG arc  

TIG氩弧改善AA6016和AA2519铝合金搅拌摩擦焊搭接接头的显微组织、拉伸性能和耐蚀性能

作　　者：Tie YI Sheng-dan LIU Chen FANG Geng-duo JIANG Xuan-xuan DAI 易铁;刘胜胆;方晨;江耿铎;戴轩轩(中南大学材料科学与工程学院,长沙410083;中南大学轻质高强结构材料国家级重点实验室,长沙410083;中南大学有色金属材料科学与工程教育部重点实验室,长沙410083;华南理工大学机械与汽车工程学院,广州510640)

机构地区：[1]School of Materials Science and Engineering,Central South University,Changsha 410083,China [2]National Key Laboratory of Science and Technology on High-strength Structural Materials,Central South University,Changsha 410083,China [3]Key Laboratory of Non-ferrous Metals Materials Science and Engineering,Ministry of Education,Central South University,Changsha 410083,China [4]School of Mechanical and Automotive Engineering,South China University of Technology,Guangzhou 510640,China

出　　处：《Transactions of Nonferrous Metals Society of China》2025年第2期405-417,共13页中国有色金属学报(英文版)

摘　　要：The effects of tungsten inert gas arc-assisted friction stir welding(TIG-FSW)on the microstructure,tensile properties and corrosion resistance of AA6016 and AA2519 alloys lap joints were investigated by means of optical microscope,scanning electron microscope,tensile test at room temperature,corrosion immersion tests and electrochemical measurements.The results show that the introduction of TIG arc during FSW process results in a more uniform microstructure of the joint with no tunnel hole defects.Furthermore,it enhances tensile strength and elongation of the joint with increased rates of 11.5%and 50.0%,respectively;meanwhile,the corrosion current density and largest corrosion depth are decreased with reduction rates of 78.2%and 45.7%,respectively.TIG-FSW can promote flow,contact and diffusion of materials,thus improving microstructure of the joint.Additionally,it reduces the size and number of secondary phase particles.Consequently,these factors contribute to the higher tensile properties and corrosion resistance of the joints.采用光学显微镜、扫描电子显微镜、室温拉伸试验、腐蚀浸泡试验和电化学测试等方法,研究了TIG氩弧辅助搅拌摩擦焊接(TIG-FSW)对AA6016和AA2519铝合金搭接接头显微组织、拉伸性能和耐蚀性能的影响。结果表明,在FSW过程中引入TIG氩弧后,接头的显微组织更加均匀,且不存在隧道孔缺陷。此外,它提高了接头的抗拉强度和伸长率,提高率分别为11.5%和50.0%;同时,降低了腐蚀电流密度和最大腐蚀深度,降低率分别为78.2%和45.7%。TIG-FSW能促进材料的流动、接触和扩散,从而改善接头的显微组织。另外,它还使第二相粒子的尺寸减小、数量减少。因此,这些因素有助于提高接头的拉伸性能和耐蚀性能。

关 键 词：friction stir welding lap joint dissimilar aluminum alloys secondary phase particles MICROSTRUCTURE tensile properties corrosion resistance 

分 类 号：TG453.9[金属学及工艺—焊接]