Weld deposition of nickel on titanium for surface hardening with Ti-Ni-based intermetallic compounds

Despite its excellent bulk mechanical properties, titanium performs poorly in tribological applications. Efforts to overcome this shortcoming have focused mainly surface modification using laser cladding with ceramic additives or intermetallic compounds (IMCs) formed during cladding. We present an alternative method using weld deposition for the production of IMC-based hard surface layer on titanium using gas metal arc welding (GMAW) with nickel as the filler wire. We observe formation of different Ti-Ni based IMCs (Ti2Ni, NiTi and Ni3Ti) in the fusion zone which results in considerable hardening of the surface. Microstructural characterization of the deposited samples give insight into the formation of IMCs.