2195铝锂合金焊接性能研究

Research on welding properties of 2195 al-li alloy

采用手工氩弧焊焊接工艺,通过十字搭接裂纹敏感性试验方法来测定焊接裂纹敏感性,以此研究了焊丝成分变化对2195铝锂合金焊接结晶裂纹率、液化裂纹率的影响。试验过程综合优化了2195铝锂合金焊丝成分、焊接方式及焊接工艺参数,并对焊接接头的宏观形貌及微观组织、断裂特征和焊接接头力学性能等进行了测试和分析。研究结果表明:在焊接电流108 A、焊接速度110 mm/min的焊接工艺参数基础上,采用Al-Si-Cu-Ce-Sc合金系焊丝及两面三层焊方式,对2195铝锂合金进行焊接,晶粒内部析出很多强化相,重复受热使得整个焊接接头的强度和延伸率都较高,可以获得结晶裂纹率K1<5%、液化裂纹率K2=0、强度系数达到0.6以上的焊接接头。

The crack sensitivity of manual argon arc welding joint was measured by cross lap crack sensitivity test.The effect of the composition of the welding wire on the crack rate of crystallization and liquefaction for 2195 Al-Li alloy weld was studied.In the test process,the composition,welding mode and welding process parameters of 2195 Al-Li alloy welding wire were comprehensively opti⁃mized,the macroscopic morphology and microstructure of the welded joint were observed,the fracture characteristics of the welded joint were analyzed,and the mechanical properties of the welded joint were tested.The research results show that,when 2195 Al-Li alloy is welded using Al-Si-Cu-Ce-Sc alloy welding wire,and the welding current is 108A,welding speed is 110 mm/min,the two sides three-layer welding way are used,many strengthening phase are precipitated inside the grain,and repeat heat improve the whole welded joint strength and elongation,so that the welded joint with the crystallization crack rate K1<5%,liquefied crack rate K2=0,and welded joint strength coefficient with 0.6 above can be obtained.