Improved wear resistance and mechanical properties of Al matrix with TiAl-based coatings

Ti-45Al-7Nb-2V-2Cr alloy coating was prepared on the surface of the 5083 aluminium alloy by HVAF technology to protect the substrate from wear attacks. The microstructure and phase composition of the coating were characterized and analysed by scanning electron microscope and X-ray diffraction, and the bonding strength and elastic modulus of the coating were accordingly measured. There were metallurgical bonding and mechanical bonding between the particles in the Ti-45Al-7Nb-2V-2Cr alloy coating, and the bonding mode between the coating and aluminium alloy substrate was mechanical bonding. The Ti-45Al-7Nb-2V-2Cr alloy coating was mainly composed of γ-TiAl, α2-Ti3Al, and β-Ti phase. The microhardness of the aluminium alloy Ti-45Al-7Nb-2V-2Cr alloy coating was increased by more than four times higher than that of the substrate, and the wear volume was reduced by more than 69%. The wear mechanism of the coating was abrasive wear and oxidation wear, which possessed excellent wear resistance.