工艺参数对MIG焊铝铜合金焊缝组织的影响

Influence of process parameter of MIG welding on the weld of Al-Cu alloy

研究了电磁搅拌工艺参数对2219铝铜合金脉冲MIG焊焊缝形状和组织的影响．结果表明,随着磁感应强度增加,焊缝枝晶数量减少,等轴晶数量增加,焊缝由指状熔深变为成形良好的椭圆形熔深．当磁感应强度和频率匹配合适时,焊缝成形良好, 焊缝组织几乎为细小的等轴晶．但随着磁感应强度继续增加,焊缝成形变差,焊缝等轴品数量减少,枝晶数量增多．电磁搅拌频率对焊缝成形影响不大,频率较低和较高时都会降低焊缝组织的细化效果．

The effects of electromagnetic stirring parameters on the shape and microstructure of MIG weld for 2219 aluminum alloy were investigated . The results showed that the number of dendrite grains gradually decreased and the equiaxed grains gradually increased with the increasing of magnetic intensity, the finger-like penetration of weld shapes transformed into elliptical penetration. With optimum magnetic intensity and frequency, the weld microstructures were almost fine equiaxed grains and the weld shape was the best. But with magnetic intensity further increasing, the shape of weld became worse, the number of equiaxed grains gradually decreased and dendrite grains gradually increased. Electromagnetic frequency had little effect on the shape of weld. Low frequency or high frequency electromagnetic field would weaken the effect of weld grains refinement.