Tribological behavior of SiC particle reinforced copper matrix composites

Copper matrix composites reinforced with SiC particulates were fabricated by making use of powder metallurgy and hot extrusion processes. The friction and wear behaviors of the composite in dry-sliding against SAE-52100 steel were evaluated on an MM-200 test rig in a block-on-ring contact configuration. The worn surface and cross-section morphologies of the composite were observed on a scanning electron microscope, while the elemental composition of the worn composite surface was determined on an energy dispersive spectrometer. It was found that the SiC particulates as the reinforcing agent contributed to significantly increase the wear-resistance of the Cu-matrix composite, though the reinforcing agent led to an increase in the friction coefficient to some extent owing to the plowing action of the hard SiC particulates and the formation of a mechanically mixed layer of much higher hardness than the bulk composite on the worn composite surface. The improved wear-resistance of the Cu-matrix composite was closely related to the load-carrying action of the SiC particulates and their actions in restraining the adhesion between the composite and the counterpart steel and the plastic deformation of the composite as well. Moreover, the mechanically mixed layer formed on the worn surface of the Cu-matrix composite also contributed to increasing the wear-resistance. The Cu-matrix composite was characterized by the abrasive wear which is and the delamination wear attributed to the crack propagation in the sub-worn surface.