Effect of SiC particulate sizes on the mechanical properties of Al-6Ti-6Nb matrix composites prepared by a mechanical alloying technique

The room-temperature mechanical properties of three kinds of SiC particulate-reinforced Al-6Ti-6Nb matrix composites are lower compared with that of an Al-61-6Nb matrix alloy, but the composites exhibit excellent elevated temperature strength and thermal stability. Of the three kinds of particulates - m-SiCp, μ-SiCp and n-SiCp - the μ-SiCp-reinforced matrix manifested the best high temperature performance. The different strength change behavior with increasing temperature can be mainly attributed to the relatively more effective strengthening from Al₃Ti, AlNb₂ intermetallic particles by the incorporation of SiC particulates.