Effects of Different Deposition Strategies on Prior-β Grain Morphology of Wire and Arc Additive Manufactured Ti-6Al-4V Components

Macrostructural characterization was performed for Ti-6Al-4V components fabricated by wire and arc additive manufacturing (WAAM) to investigate the effects of different deposition direction and interlayer dwell time on prior-β grain morphology. The bidirectional and unidirectional travel directions led to different growth directions of columnar prior-β grains. By extending the interlayer dwell time between each deposited layer to 120 s, the full equiaxed prior-β grains were obtained. The results indicate that the equiaxed prior-β grains at the bottom of the deposited wall are caused by recrystallization. The sizes of the equiaxed prior-β grains at the bottom are both affected by the thermal cycle and the recrystallization.