Publication

Abstract : Metal matrix nanocomposites use Al-Zn-Mg alloys because of their high strength-to-weight ratio, low density, and good castability. However, the low melting temperatures, modulus, and elasticity limit its use for functional applications. Nanoceramic reinforcements can enhance such alloy performance. Nano B4C/Gr-reinforced Al-Zn-Mg alloy composites were synthesized by vacuum-assisted stir casting with B4C weight proportions of 2 wt%, 4 wt%, and 6 wt%, retaining 2 wt% constant with Gr. The microstructure of the hybridized nanocomposites exhibits a homogeneous dispersion of reinforcement particles inside the matrix alloy, with no evidence of any residual pores. XRD analysis revealed that the interfacial phases between the hybrid composites are identified as ternary alumino-boron carbide (Al₃BC), aluminum boride (AlB₁₂), magnesium silicide (Mg₂Si), and silicon dioxide (SiO₂), and they serve as a strengthening mechanism of synthetic composites. As a result of the experiments, the Al-Zn-Mg alloy composite’s microhardness is improved by 27.75±0.03 HV compared to the base alloy, tensile strength (36.36±0.2 MPa), compressive strength (35.97 %±0.02 MPa), flexural strength (29.65±0.01 MPa), and impact properties (28.57±0.02 J/m2). This is due to enhanced grain refinement and improved wettability as compared to the as-cast Al-Zn-Mg alloy. Moreover, the inclusion of higher-density nano reinforcement slightly increased the density of hybrid nanocomposites (0.080±0.001 g/cc). The corrosion and wear loss percentage was improved to a maximum of 31.15±0.03 % mm/year x10–6 and 36.48±0.01 % g due to the reduction of interdendritic corrosion along the grain boundaries and inferior adhesive wear for process innovation.