Dry sliding wear behaviour of Al–12Si and Al–12Si–3Cu cast alloys

This paper attempts to investigate the influence of the microstructural changes on the dry sliding wear behaviour of Al–12Si and Al–12Si–3Cu cast alloys by grain refinement (Al–1Ti–3B), modification (Al–10Sr) and combined action of both (Al–1Ti–3B + Al–10Sr). Results indicate that combined grain refined and modified Al–12Si–3Cu cast alloys have microstructures consisting of uniformly distributed α-Al grains, eutectic Al–silicon and fine CuAl2 particles in the interdendritic region. These alloys exhibited better wear resistance in the cast condition compared with the same alloy subjected to only grain refinement or modification. The improved wear resistances of Al–12Si–3Cu cast alloys are related to the refinement of the aluminum grain size, uniform distribution of eutectic Al–silicon and fine CuAl2 particles in the interdendritic region resulting from combined refinement and modification.