Microstructure and Wear Resistance of Plasma Jet Clad Ti₅Si₃/NiTi Composite Coating

A wear resistant Ti₅Si₃/NiTi composite coating was fabricated on a substrate of a titanium alloy by plasma jet cladding using Ni-Ti-Si elemental powder blends. The microstructure, microhardness and wear resistance of the coating were evaluated. The result shows that the plasma jet clad composite coating has a rapidly solidified microstructure consisting of blocky primary Ti₅Si₃ and the inter-blocky Ti₅Si₃/NiTi eutectics and is metallurgically bonded to the titanium substrate. The composite coating has high hardness and excellent wear resistance under the dry-sliding-wear test condition.