Solidification observations and sliding wear behavior of cast TiC particulate-reinforced AlMgSi matrix composites

Al7Mg5Si-based TiC reinforced composites have been produced by casting methods. The microstructures of the monolithic alloy and the composite materials are explained in terms of solidification phenomena. The TiC presence significantly alters the matrix microstructure both by causing extensive grain refinement and by altering the extent and morphology of the Mg2Si phase. The TiC particles serve as potential nucleation sites for the Mg2Si phase. The effect of the TiC reinforcing particles on the sliding wear performance at the composites has also been investigated. TiC additions improve the overall wear rate of the monolithic alloy. A likely wear mechanism is proposed, based on wear rate and friction coefficient data along with wear track and debris examination.