Eight-millimeter-thick high-strength AA2219 aluminum alloy plates were successfully welded by variable polarity tungsten inert gas welding, and the effect of cold spraying (CS) process on the residual stress, microstructure and mechanical properties of the welded joints were investigated. The CS experiment was performed under different driving gas temperatures and pressures and with different powder types. The microstructure of the as-welded joints and as-coated joints was analyzed by optical microscopy and scanning electron microscopy, while the residual stress was measured by the blind-hole-drilling method. The results show that the CS process could significantly modify and re-distribute the residual stress of the welded joints. The maximum residual tensile stress of the welded joint has been significantly reduced by 111.9% and distributed more uniformly compared to the as-welded state. With the increase in gas temperature and/or pressure in CS, the residual tensile stress of joints was reduced, and even some compressive stress appeared. Among the powders of Cu, Al, and Ni, Cu particles have the best-improving effect. In addition, double-sided spraying treatment can reduce the residual tensile stress of both sides more effectively. Besides, the grain size of the joint surface after CS was refined.

中文翻译：

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采用冷喷涂改变工件残余应力分布：AA2219 熔焊接头案例研究

采用变极性钨极惰性气体保护焊成功焊接了8毫米厚的高强度AA2219铝合金板，研究了冷喷涂(CS)工艺对焊接接头残余应力、组织和力学性能的影响。CS 实验是在不同的驱动气体温度和压力下以及使用不同的粉末类型进行的。采用光学显微镜和扫描电镜对焊缝和涂层接头的显微组织进行分析，残余应力采用盲孔钻孔法测量。结果表明，CS工艺可以显着地改变和重新分布焊接接头的残余应力。焊接接头的最大残余拉应力显着降低了111。9% 并且与焊接状态相比分布更均匀。随着CS中气体温度和/或压力的增加，接头的残余拉应力降低，甚至出现一定的压应力。在Cu、Al、Ni粉末中，Cu颗粒的改善效果最好。此外，双面喷涂处理可以更有效地降低双面的残余拉应力。此外，CS后接合面的晶粒尺寸被细化。双面喷涂处理可以更有效地降低双面的残余拉应力。此外，CS后接合面的晶粒尺寸被细化。双面喷涂处理可以更有效地降低双面的残余拉应力。此外，CS后接合面的晶粒尺寸被细化。