A wear resistant intermetallic matrix
composite coating with Ti 5Si 3 as the reinforcing phase was fabricated on titanium
alloy BT9 by laser cladding with Ni 59Ti 21Si alloy powders as the raw material.
Microstructure of the coating was characterized by optical microscopy, scanning electron microscopy, X ray diffraction and energy dispersive spectroscopy. Wear resistance of the
composite coating in dry sliding against SAE52100 steel was evaluated at ambient condition, using AISI1045 steel specimen as the reference. Results indicate that the laser clad intermetallic composite coating had a rapidly solidified homogeneous microstructure consisting of Ti 5Si 3 primary particles uniformly distributed in the NiTi 2 Ti 5Si 3 β eutectic matrix and was metallurgically bonded to the titanium substrate. The laser clad composite coating had high hardness and excellent wear resistance under dry sliding wear test conditions. This was attributed to the formation of the hard Ti 5Si 3 and NiTi 2 intermetallic phases and the refined microstructure of the coating.