Effect of brass slag particles on the microstructure and hardness of Al-Si alloy matrix composites

Abstract The current study investigated the effects of brass slag particles on the microstructure and hardness of Al-Si alloy (LM30) matrix composite. Stir casting was used to fabricate a composite with brass slag particles of finesize (i.e. 100–215 μm), coarse size(i.e. 215–350 μm) and three different concentrations of 3 wt%, 6 wt%, and 9 wt%. The dynamic shear force generated by stirring prevents brass slag particles from sinking into the melt which result in uniform particle dispersion throughout the melt. Optical microscopy analysis reveals a uniform distribution of reinforcement particles in cast composites, accompanied by silicon refinement. The findings suggest that the incorporation of industrial waste (brass slag as a reinforcement) in the fabrication process enhances microstructure and mechanical characteristics of composites. 9 wt% concentration of brass slag reinforced of fine size composite demonstrated an impressive ∼60.7% improvement in hardness compared to base alloy (LM30). It was also observed that theoretical density ( ρ th) and experimental densities ( ρ ex) approximately 25% and 18.4% greater than that of the base alloy (LM30).