高强铝铜合金MIG焊焊缝组织细化研究  

Study on Microstructure Refinement of MIG Welds of High Strength Al-Cu Alloy

作　　者：杨成刚[1] 邢丽[1] 国旭明[2] 

机构地区：[1]南昌航空大学材料科学与工程学院,江西南昌330063 [2]沈阳航空工业学院材料科学与工程学院,辽宁沈阳110136

出　　处：《热加工工艺》2008年第15期100-102,共3页Hot Working Technology

基　　金：国家863计划资助项目(2002AA305402)

摘　　要：研究了复合脉冲、电磁搅拌对高强Al-Cu合金MIG焊焊缝组织及性能的影响。结果表明:电磁搅拌降低了固-液界面前沿液相的温度梯度,增加了非均质形核率,促使粗大、方向性很强的柱状晶转变为细小的等轴晶,显著提高了焊接接头强度和塑性;复合脉冲焊接时,峰值电流周期性变化引起的熔池液体的搅拌作用较弱,降低了焊缝组织细化效果。The effects of synergic pulse and electromagnetic stirring on the microstructures and properties of the weld of high strength Al-Cu alloy were investigated. The results show that electromagneticl stirring decreases the temperature gradient at the solid-liquid interface in the welding pool and enhances the density of heterogeneous nucleation, changes the coarse and oriented columnar grains into fine equiaxed grains, increases the tensile strength and elongation of weld metals. The stirring action of the liquid metals in welding pool resulting from peak-current periodically fluctuating is weaker during synergic pulsed MIG welding, which decreases the refinement effect on weld mierostructure.

关 键 词：高强铝铜合金 复合脉冲 电磁搅拌 焊缝组织 

分 类 号：TG146.2[一般工业技术—材料科学与工程] TG444.74[金属学及工艺—金属材料]