Influence of CaF2 on the microstructure and properties of wire-arc additive manufactured TA15

Wire-arc additive manufacturing (WAAM) process has advantages such as high deposition efficiency, large-scale parts, and low production costs. However, the TA15 titanium alloy fabricated by WAAM still exhibits issues including coarse grain, low strength and hardness, as well as poor corrosion resistance. This study introduces activating fluxes of CaF₂ into the WAAM process. The results show that CaF₂ additions refines the plate-like α phase and inhibits the transition of β to α phase. The improved microstructure increases the tensile strength by 8.36%, the hardness by 14.2%. Moreover, the corrosion potential and current increase (or decrease) from -0.395V, 6.384×10^-6A/cm³ to -0.294V, 2.499×10^-6 A/cm². Therefore, this study provides a potential approach for improving the microstructural properties of WAAM-prepared titanium alloy (TA15).