(中南大学 材料科学与工程学院， 长沙 410083)
摘 要: 采用进口4047焊丝对2519铝合金进行熔化极惰性气体保护焊（MIG）， 对焊接接头的力学性能和显微组织进行了研究。结果表明， 2519铝合金焊接性能较好，由于热循环的作用， 焊接接头的力学性能相对于基材发生了较大变化。 2519铝合金焊接接头的力学性能低于基材的性能，焊缝处是合金接头的最薄弱环节， 其次是焊接热影响区内的软化区， 强化相粒子发生过时效而粗化是形成软化区的主要原因。
关键字: 2519铝合金；焊接接头； 显微组织
（ School of Materials Science and Engineering， Central South University， Changsha 410083， China）
Abstract: 2519 aluminum alloy was welded by using imported 4047 welding wire with method of MIG. The mechanical properties and microstructures of welded joint were studied. The results show that the weldability of 2519 aluminum alloy is fairly good, but due to the weld thermal cycle, the mechanical properties of the welded joint have changed greatly to the base metal relatively. The mechanical properties of 2519 aluminum alloy welded joint are worse than those of the base metal. The weld zone is the weakest point in welded joint, and the soften zone in heat-affected zone(HAZ) is the second weakest point in welded joint, which is formed due to the overageing of the main strengthening phase particles leading to coarsening.
Key words: 2519 aluminum alloy; welded joint; microstructure
