NiTi Surface Layers by Plasma Transferred Arc Surfacing Process for Improving Wear Resistance of Titanium

In order to improve wear resistance of titanium, fabrication of NiTi intermetallic compounds as a surface layer by plasma transferred arc surfacing process (PTA process) was investigated. Powder of unalloyed nickel was fed into the plasma during the PTA process and NiTi intermetallic layers were successfully synthesized. The surface layers have no cracks and blowholes with optimized conditions of the PTA process. The surface layers that largely consist of NiTi intermetallic phase could be achieved, while the microstructures of them were significantly influenced by the conditions such as the arc current. The NiTi layers exhibited high resistance to sliding wear under non-lubricated conditions and were much more resistant than titanium.