Microstructural, mechanical and tribological properties of Al matrix composites reinforced with Cu coated Ti₃AlC₂

Al matrix composites reinforced with Ti₃AlC₂and Cu coated Ti₃AlC₂were prepared by hot-press sintering approach. It was confirmed that Ti₃AlC₂displayed poor wettability with Al, resulting in the poor interfacial bonding strength between Ti₃AlC₂and Al matrix. However, Al₂Cu layer could be formed due to the reaction between Cu and Al during the sintering process, when Cu coated Ti₃AlC₂was incorporated in Al matrix. Because of the formation of enhanced Al₂Cu interface, the mechanical and tribological properties were significantly improved. The Al₂Cu layer could bridge Ti₃AlC₂particle and Al matrix effectively, which contributed to absorbing energy when load was applied, to provide better mechanical properties. Moreover, Ti₃AlC₂particle could exhibit powerful pinning effect to inhibit two-body abrasion and adhesion wear, which was favorable for forming smooth tribo-oxidation surface to yield low friction coefficient. The wear mechanism was believed to be oxidation and fatigue wear.