Microstructural, mechanical, and tribological evaluation of Al7075 reinforced with B4C and graphene particulates produced by stir casting

This study investigated the mechanical and tribological properties of Al7075 alloy reinforced with B4C and graphene particles, processed through stir casting. It focused on incorporating a constant 5wt% Boron Carbide and varying graphene concentrations (1 to 4wt%) into the Al7075 matrix. Microstructural analysis was conducted using optical microscopy and Scanning Electron Microscopy, revealing finer grains, a reduction in grain size and the formation of a homogeneous dispersion of particles in Al7075 composites. Al7075/5wt.%B4C/4 wt.% graphene composite achieved the maximum ultimate tensile strength (UTS) of 421.77 MPa and Brinell hardness of 129.3 HB. Additionally, the tribological performance of the composites was assessed, with a wear rate of 0.0093 mm 3 /m recorded for the Al7075/5wt% B4C/3wt% graphene composite, demonstrating improved wear resistance. Magnesium, oxygen, and traces of silicon were detected through the EDS analysis. The detection of oxygen shows that the formation of an oxide, and the silicon detected has been derived from the composition of the alloy Al7075. Overall, this study provides valuable insights into the development of cost-effective, high-performance composites suitable for industrial applications.