Tribological Property of Surface Hybrid Composite Layer Fabricated on Aluminum Alloy 7075 by FSP

In this study, friction stir processing (FSP) has been used to fabricate aluminum alloy 7075 based surface hybrid composite with a mixture of SiC and MoS2 reinforcement particles. The surface hybrid composite layer has been successfully fabricated at different content ratio of SiC and MoS2 particles by one-pass FSP. The SiC and MoS2 particles were distributed almost homogeneously over the nugget zone. The average Vickers hardness at nugget zone increased to about 190 at 100% SiC, and it decreased with increasing the MoS2 content ratio in reinforcement. The wear weight loss of the surface hybrid composite depended on the applied load and the relative content ratio of SiC and MoS2 particles. The surface hybrid composite of 75% SiC and 25% MoS2 showed superior wear resistance among all tested samples. The wear failure was attributed to the combination of the combination of abrasive wear and delamination.