超声振动辅助A7N01铝合金激光-MIG复合焊接组织及力学性能  

Microstructure and mechanical property of A7N01 aluminum alloy welded by laser-MIG hybrid method with assisting ultrasonic vibration

作　　者：朱宗涛[1] 祝全超 李远星[1] 陈辉[1] 

机构地区：[1]西南交通大学材料科学与工程学院,成都610031

出　　处：《焊接学报》2016年第6期80-84,132-133,共5页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51405398);中央高校基本科研业务费专项资金资助(2682015CX007)

摘　　要：文中针对铝合金激光-MIG复合深熔焊过程易出现气孔缺陷问题,设计了超声振动辅助的焊接方法.通过对堆焊试样的X射线探伤和截面的宏观金相观察,对比了超声振动对气孔的数量、大小以及分布位置的影响.同时研究了超声振动作用对A7N01铝合金激光-MIG复合熔覆层的成形、组织及力学性能的影响.结果表明,在超声振动作用下,激光-MIG复合堆焊熔覆层气孔的数量明显减少,小尺寸气孔发生聚集并有上浮趋势;熔合线附近的柱状晶组织宽度明显小于无超声辅助的熔覆层;超声振动辅助激光-MIG复合焊接接头各区的冲击吸收功和抗拉强度都有一定程度的提高,具有一定的应用优势.To solve the porosity defects in aluminum alloy joints obtained by laser-MIG hybrid deep-penetration welding,this article presents a novel laser-MIG hybrid welding method through applying ultrasonic vibration to the work piece. The number,size and distribution position of porosities in building-up layer on A7N01 aluminum alloy are investigated by X-ray detection and cross-section observation in stereo microscope. The effects of ultrasonic vibration on the morphology,microstructure and mechanical properties of the joints are also studied. The results show that the number and size of the porosities in buildingup layer by laser-MIG hybrid welding significantly decrease,due to ultrasonic vibration accelerating the gathering and rising of small size porosities. The belt of columnar grains along fusion line near the building-up layer becomes thinner with the effects of ultrasonic vibration. The impact toughness and tensile strength are improved in some extent due to the introduced ultrasonic vibration in the laser-MIG hybrid welding method,so that it is supposed to be a good way for aluminum alloy welding.

关 键 词：铝合金 激光-MIG复合焊 超声 气孔 

分 类 号：TG456.9[金属学及工艺—焊接]