磁搅拌对铝铜合金MIG焊缝形状、组织及性能影响

Effect of Electromagnetic Stirring on the Shape,Structure and Mechanical Properties of Al-Cu Alloy MIG Weld

研究电磁搅拌对2219铝铜合金脉冲MIG焊焊缝形状、组织及性能的影响。实验结果表明,电磁搅拌使MIG焊缝由指状熔深变为椭圆形熔深,改善焊缝成形。电磁搅拌通过增加焊缝中非均质形核核心,降低固液前沿液相的温度梯度,促进粗大柱状晶和枝晶转变为细小等轴晶,提高焊缝金属的强度和塑性。

Effects of electromagnetic stirring on the shape, structure and mechanical properties of pulse metal inert gas （MIG） weld of 2219 Al-Cu alloy were investigated. The results show that electromagnetic stirring modifies the shape of aluminum alloy MIG weld, the finger-like shape penetration of weld changing to elliptical penetration. Electromagnetic stirring promotes the coarse and oriented columnar grains and the dendrites transforming into the equiaxed grains through increasing heterogeneous nuclei in weld metal and decreasing temperature gradient just ahead of the solid-liquid interface. As a result, the microstructures of weld are refined and the strength and ductility are increased.