Study on Electro-Spark Deposition Welding of Ultra-thin Sheet of Ti-6.5Al-1Mo-1 V-2Zr Alloy

In this work, butt welding experiment of Ti-6.5Al-1Mo-1 V-2Zr alloy sheet of 0.5 mm thickness was performed via electro - spark deposition method. The results of the experiment indicate that the reactive titanium alloy’s surface is free from oxidation without trailing shielding protection due to low heat input and rapid thermal cycles associated with the process. The fusion zone is mainly composed of equiaxed microstructure of martensite α′ and α dual phases, wherein the amount of α′ in the central joint is higher than that adjacent to the base metal. The maximum tensile strength of the welded joint can reach 1187 MPa, which is 95% of the base metal. Besides, the joint shows obvious plastic deformation before fracture. The findings have demonstrated the possibility of widely applying the welding methodology to thin sheets of titanium alloys.