Dry sliding wear behaviour of a novel 6351 Al-Al4SiC4 composite at high loads

In this research work the dry sliding wear behaviour of 6351 Al alloy and 6351 Al based composites possessing varying amount of (2–7 vol%) insitu Al₄SiC₄ reinforcement was investigated at low sliding speed (1?m?s^?1) against a hardened EN 31 disk at higher loads (44 N and 68.7 N). In general, at higher loads, the wear mechanism involved microcutting and microploughing abrasion. In most occasions, Al₄SiC₄ reinforced 6351 Al based composites exhibited much higher wear rate (lower wear resistance) than the unreinforced 6351Al alloy. This was mainly attributed to the removal of reinforcement particle through microcutting abrasion process that resulted in cavitation and subsequent microploughing abrasion for rapid removal of material from surface. This is on contrary to the author's previous research work, where at lower loads (24.5 N or below), Al₄SiC₄ particles stood tall to enhance wear resistance of 6351 Al-Al₄SiC₄ composite.