Influence of Post-Deposition Heat Treatments on the Microstructure and Tensile Properties of Ti-6Al-4V Parts Manufactured by CMT-WAAM

Cold metal transfer (CMT)-based wire and arc additive manufacturing (WAAM) of Ti-6Al-4V alloy has been investigated to manufacture walls with two different building strategies. This study focuses on the influence of the application of thermal treatments on the resulting microstructure and mechanical properties. Deep microstructural analysis revealed different grades of growth of lamellae alpha phase after several thermal treatments at different temperatures, which lead to different tensile mechanical properties and better strength and ductility balance compared to the as-built condition. Results are compared with equivalent forged and casting standards and the state of the art for WAAM of Ti-6Al-4V alloy. At temperatures of 920 degrees C, anisotropy was maintained and elongation increased by 70% while yield strength and UTS was slightly decreased by 8%.

Automated summary

The study investigates the CMT-based wire and arc additive manufacturing of Ti-6Al-4V alloy for manufacturing walls with two building strategies, focusing on the influence of thermal treatments on microstructure and mechanical properties. Microstructural analysis revealed different growth grades of lamellae alpha phase after thermal treatments at various temperatures, leading to improved strength and ductility balance compared to the as-built condition. At 920 degrees C, anisotropy was maintained with a 70% increase in elongation and a slight decrease in yield strength and UTS.