Influence of sliding speed on the dry sliding wear behaviour and the subsurface deformation on hybrid metal matrix composite

In recent years, more attention is being paid to the structure of both the surface and the subsurface of a material being subjected to wear. Surface and subsurface deformation can cause a considerable change in the microstructure of the material leading to a change in its properties. The present study investigates the influence of sliding speed on dry sliding wear behaviour and the extent of subsurface deformation in aluminium metal matrix composites, namely Al 2219/15SiCp and Al 2219/15SiCp-3graphite all fabricated by the liquid metallurgy route. Dry sliding wear tests were conducted using a pin-on-disc machine. The subsurface deformation was assessed as a measure of variation in microhardness along the depth normal to the cross-section of the worn surface. The results reveal that with increasing sliding speeds in the mild wear region the degree of subsurface deformation was also increasing. The graphitic composite exhibited less degree of subsurface deformation in comparison to the graphite free composite.