2024铝合金填丝TIG焊接头搅拌摩擦加工组织和性能研究  

Investigation into the Microstructure and Properties of 2024Al TIG Joint with Wire Filler Subjected to Friction Stir Processing

作　　者：吴洁 沈以赴[2] 黄国强[2] WU Jie;SHEN Yifu;HUANG Guoqiang(College of Integrated Circuit Science and Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003;State College of Materials Science and Technology,Nanjing University of Aeronautics and Astronautics,Nanjing 211106)

机构地区：[1]南京邮电大学集成电路科学与工程学院,南京210003 [2]南京航空航天大学材料科学与工程学院,南京211106

出　　处：《机械工程学报》2024年第20期153-161,共9页Journal of Mechanical Engineering

基　　金：国家自然科学基金资助项目(52205436)。

摘　　要：熔化焊方法在铝合金连接方面发挥着重要作用,但所产生的焊缝存在一些冶金问题。因此,针对铝合金熔化焊焊缝开发具有较高加工柔性裕度的有效改性/修复工艺尤为迫切,这对提高接头服役性能、延长服役寿命具有重要工程意义。通过对使用ER4043焊丝典型AA2024铝合金TIG焊接头焊缝进行搅拌摩擦加工(Frictionstir processing,FSP),研究了FSP对熔焊缝微观结构和性能的影响规律。结果表明,TIG焊接头焊缝由粗大铸态树枝晶、Al-Si共晶网和冶金缺陷组成;经FSP处理后,焊缝铸态组织被完全消除,转变为致密、均匀、细晶的Si颗粒增强复相组织,导致TIG焊接头强塑性和耐蚀性同步提升。建立了FSP前后TIG焊接头微观结构演变与性能改善之间的构效关系,揭示了TIG焊接头FSP后性能提高的微观结构根源,为其他合金体系熔焊接头改性/修复提高性能提供新的思路和方法。The fusion welding methods play an important role in joining aluminum alloys,but the resulting welds suffer from a number of metallurgical issues.Therefore,it is particularly urgent to develop the effective modification/repair processes with high machining flexibility margin for aluminum alloy fusion welded joints,which is of great engineering significance for them to improve the service performance and extend the service life.A typical AA2024 aluminum alloy TIG welded joint using ER4043 wire was subjected to friction stir processing(FSP).The effect of FSP on the microstructure and properties of TIG joint was investigated.The results show that the fusion zone consists of coarse cast dendrites,Al-Si eutectic network and metallurgical defects;after FSP,the cast structure in the fusion zone is completely eliminated and transformed into a dense,uniform and fine-grained aluminum matrix composite reinforced with Si particle,resulting in a simultaneous improvement in strength-ductility synergy and corrosion resistance of TIG joint.The constitutive relationship between the microstructure evolution and property improvement of TIG joint before and after FSP is established,which reveals the microstructural origin of the performance improvement for the TIG joint after FSP,and provides new insights into the modification/repair of fusion welds of many metallic systems for enhanced performance.

关 键 词：铝合金 TIG焊接头 搅拌摩擦加工 改性与修复 

分 类 号：TG156[金属学及工艺—热处理]