Study on Microstructure and Thermal Cracking Sensitivity of Deposited Ti6Al4V/Inconel 718 Composites Made by Two-Wire Arc Additive Manufacturing by Current

Ti6Al4V/Inconel 718 composites were prepared using arc additive manufacturing technology at different deposition currents. The properties of the composites directly influence the performance of the gradient materials, while heat input further affects the composites' properties. The results indicate that at a deposition current of 35 A, Ti elements diffuse into the Inconel 718 alloy. Increasing the current leads to the formation of brittle intermetallic compounds such as TiNi, Cr₂Ti, and Fe₂Ti in the deposited layer. At deposition currents below 50 A, no cracks appear, but cracks develop at a current of 50 A. Additionally, the microhardness of the deposited layer increases with higher deposition currents. Compared to the 35 A condition, microhardness rises by 31.51% at a current of 50 A. This research can expand the application field of the arc additive manufacturing of direct deposition Ti6Al4V/Inconel 718 composites.