摘要
研究了分别采用熔化极氩弧焊(MIG)和钨极氩弧焊(TIG)进行2024铝合金焊接的工艺,并对在两种工艺条件下获得的接头的力学性能和微观组织结构进行测试分析。试验结果表明,MIG焊接头的抗拉强度达到母材抗拉强度的60%以上,而TIG焊接头的抗拉强度只达到母材抗拉强度的50%,这是由于MIG焊接头焊缝组织要比TIG焊接头焊缝组织细小,晶界处共晶相数量明显减少,晶内析出了很多细小的共晶相,有利于提高接头强度;且MIG焊的热输入比TIG焊的热输入小,MIG接头软化程度也比TIG焊要小。因此在试验条件下,MIG焊工艺获得接头的性能要优于TIG焊接头。
The difference of microstructure and mechanical properties of welded joints between metal inert gas are welding and tungsten inert gas arc welding of 2024 aluminum alloy were investigated.The experimental results show that weld metal microstructure of MIG welding is finer than that of TIG welding,and the number of enteetie phase in the grain boundaries decrease nbviously,a number of fine euteetic phase precipitated at grain inner.So it is advantageous to increase the tensile strength of welded joints.The tensile strength MIG welding is above 60% of base metal.But the tensile strength of TIG welding is only about 50% of base metal.Besides, the heat input of MIG welding is smaller than TIG welding so that the softening degree of MIG welding is milder than TIG welding. Consequently ,the mechanical properties of welded joints with MIG are better than that of TIG at the experiment condition.
出处
《电焊机》
北大核心
2009年第7期52-55,80,共5页
Electric Welding Machine
关键词
2024铝合金
气体保护焊
微观组织
力学性能
2024 aluminum alloy
gas shielded arc welding
microstrueture
mechanical properties
