In the cold metal transfer additive manufacturing process of Ti-6Al-4V thin wall structure, ultrasonic peening treatment (UPT) in three directions is proposed to refine the large columnar prior-β grains and secondary α grains, and to improve anisotropy in tensile properties. The experimental results showed that UPT in three directions applied to each weld right after arc extinguishing has a minor influence on the surface appearance, which shows no apparent plastic deformation, but has a great improvement in grain refinement. The changes in microstructure and dislocations of thin wall structure treated by UPT in three directions were observed. By comparing with those without UPT, the main causes for refinement of columnar prior-β and secondary α grains was explored, namely mechanical effects of ultrasonic at the temperature range of α’ dissolution temperature T_diss – liquidus temperature T_l. Specimens with UPT have better properties, higher loads with the same indentation displacement in nano-indentation tests, an increase in ultimate tensile strength and a reduction in anisotropic percentage in tensile tests.

在Ti-6Al-4V薄壁结构的冷金属转移添加剂制造过程中，提出了在三个方向上进行超声波喷丸处理（UPT）的方法，以细化大柱状先验β晶粒和次生α晶粒，并改善拉伸性能的各向异性。 。实验结果表明，在电弧熄灭后，在每个焊缝上施加三个方向的UPT对表面外观的影响很小，没有明显的塑性变形，但是在晶粒细化方面有很大的改善。观察了UPT处理后的薄壁结构在三个方向的微观结构和位错变化。通过与没有UPT的那些进行比较，探讨了细化柱状先验β和次生α晶粒的主要原因，T _diss –液相线温度T _l。具有UPT的样品具有更好的性能，在纳米压痕测试中具有相同压痕位移时具有更高的载荷，极限拉伸强度增加，并且拉伸试验中的各向异性百分比降低。