Enhancing tribo-mechanical and corrosion properties of A383 aluminum matrix composites through stir-cum-squeeze casting with marble dust and hexagonal boron nitride reinforcement

Abstract

The A383 aluminum matrix composites (AMCs) are prominent automotive materials owing to their low-density yet high-strength nature. However, the conventional casting techniques, exorbitant price, and scarce supply of traditional ceramic reinforcements remain challenging. This research countermeasure the challenges by hybridizing the A383 with industrial marble dust (MD) and hexagonal boron nitride (hBN) through the stir-cum-squeeze casting technique. A constant proportion (4 wt%) of MD waste and varying proportions of hBN (1.5, 3, 4.5, and 6 wt%) were used to reinforce A383 alloy to improve its physio-mechanical characteristics. Stir-cum-squeeze casting enables homogenous dispersion of reinforcement particles within the matrix, resulting in improved interfacial bonding. Optimal results were achieved for A383 alloy reinforced with 4 wt% of MD and 6 wt% hBN, ensuring balanced tribo-mechanical characteristics against the as-casted A383. The hardness value increased by 40.8%, while the compression and tensile strength increased by 30.8% and 115.8%, respectively. Non-destructive testing confirms the effective reduction of porosity in the stir-cum-squeeze-cast composites. Moreover, the hybrid composites exhibit improved corrosion resistance by 32.18% after 72 h of testing. Additionally, the hybrid composites demonstrate a wear rate reduction of 54.35%.