Nano-Sized Al2O3-Gr Reinforced Al7075 Hybrid Composite: Impact of Cooling Agents on Mechanical, Wear, and Fracture Behavior

Aluminum metal cast composites (AMCCs) are frequently used in high-tech sectors such as automobiles, aerospace, biomedical, electronics, and others to fabricate precise and especially responsible parts. The mechanical and wear behavior of the metal matrix composites (MMCs) is anticipated to be influenced by the cooling agent's action and the cooling temperature. This research paper presents the findings of a series of tests to investigate the mechanical, wear, and fracture behavior of hybrid MMCs made of Al7075 reinforced by varying wt % of nano-sized Al2O3 and Gr and quenched with water and ice cubes. The heat-treated Al7075 alloy hybrid composites were evaluated for their hardness, tensile, and wear behavior, showcasing a significant process innovation. The heat treatment process greatly improved the hybrid composites' mechanical and wear performance. The samples quenched in ice attained the highest hardness of 119 VHN. There is a 45.37% improvement in the hardness of base alloy with the addition of 3% of Al2O3 and 1% of graphite particles. Further, the highest tensile and compression strengths were found in the ice-quenched 3% Al2O3 and 1% graphite hybrid composites with improvements of 34.2 and 48.83%, respectively, compared to the water-quenched base alloy. Under the samples quenched in ice, the mechanical and wear behavior improved. The tensile fractured surface showed voids, particle pullouts, and dimples. The worn-out surface of wear test samples of the created hybrid composite had micro pits, delamination layers, and microcracks.