Low-temperature synthesis of (TiC + Al2O3)/Al alloy composites based on dopant-assisted combustion

• Combustion reactions in the Al–TiO2–C system were studied.
• Role of excess Al for the formation of TiC was explained.
• Appropriate amounts of excess Al for forming TiC was determined.
• CuO added to the powder system caused TiC to form at low temperatures.
• (TiC + Al2O3)/Al alloy composite was synthesized at 860 °C.

A feasible approach to fabricate an Al alloy composite reinforced with TiC and Al2O3 (hereinafter, (TiC + Al2O3)/Al alloy composite) based on in-situ processing at low temperatures was proposed. With appropriate amounts of excess Al added to the (4Al + 3TiO2 + 3C) powder system, the spontaneous combustion reactions for forming TiC and Al2O3 were promoted, whereas a small amount of CuO added to the reagent powders caused triggering of the combustion reaction at lower temperatures (860 °C), which was thereafter self-maintaining. The TiC and Al2O3 particles thus formed could be dispersed uniformly in the Al matrix and contributed to a considerable increase in the strength and stiffness of the resultant composite material, demonstrating the feasibility of the proposed technique for producing metal matrix composites for load-bearing applications. In this study, we report the method used to fabricate the (TiC + Al2O3)/Al alloy composite at low temperatures, its synthesis, and the resultant properties.