Effects of Cooling Rate on the Microstructure and Tensile Properties of Wire-Arc Additive Manufactured Ti-6Al-4V Alloy

Wire-arc additive manufacturing has emerged as a technology that could replace the conventional manufacturing process of titanium alloys. However, it produces a coarse beta grain, which can accumulate via several deposited materials, resulting is strong texture and anisotropy. To investigate potential solutions, the effects of the cooling rate on the resulting microstructure and tensile properties were studied. The cooling rate of the deposited materials was adjusted by interpass temperature control. Under rapid cooling, fine alpha + alpha ' grain with a low aspect ratio were observed and tensile and hardness properties were also improved.