The influence of interfacial characteristics between SiCp and Mg/Al metal matrix on wear, coefficient of friction and microhardness

The aim of the present investigation is to characterize the interface between the SiCp as the reinforcement and Al and Mg metals of the metal matrix composites (MMCs) prepared through vacuum infiltration technique. The weight loss as an index of abrasive wear using pin-on-disc apparatus, the coefficient of friction, the microhardness value and the interparticle distance were determined under dry conditions and these results were correlated to characterize the interface as a function of properties of metal and the reinforcement. The results of the investigation indicate that interparticle distance in cast infiltrated composites strongly influences the tribological properties of these composites. Microhardness on the reinforcement particles and interparticle distance are good indicators of the strength of the interface between particle and the matrix. Magnesium base composites in general show better wettability as compared to the aluminium base composites. Coating of SiCp reinforcements with Ni and Cu generally leads to good quality interface characteristics in Al matrix composite as both microhardness and wear properties are improved. Oxidized SiCp reinforcements behave in complex manner in influencing the interfacial characteristics in aluminium/magnesium matrix composites possibly due to the formation of reaction product at the interface.