Metal Matrix Composites (MMC’s) consist of either pure metal or an alloy as the matrix material, while the reinforcement generally a ceramic material. Aluminium composites are considered as one of the advanced engineering materials which have attracted more and more benefits. Now a days these materials are widely used in space shuttle, commercial airlines, electronic substrates, bicycles, automobiles, etc., Among the MMC’s aluminium composites are predominant in use due to their low weight and high strength. The key features of MMC’s are specific strength and stiffness, excellent wear resistance, high electrical and thermal conductivity. Hence, it is proposed to form a new class of composite. Al 7075 alloy reinforced with Graphite Powder and Bagasse ash to form MMC using Stir casting. The MMC is obtained for different composition of Graphite powder and Bagasse ash particulates (varying Graphite powder with constant Bagasse ash and varying Bagasse ash with constant Graphite powder percentage). The test specimens are prepared as per ASTM standard size by turning and facing operations to conduct tensile tests, compression tests and hardness tests. The specimens are tested for tensile strength and compression strength as per ASTM standard E8 by using universal testing machine and hardness as per ASTM standard E10 at different loads by using Brinell hardness testing machine. Through the results, it is concluded that the MMC obtained has got better tensile strength, compression strength and hardness properties when compared to non-heat-treated Al 7075 alone.

This research work investigated the in?uence of graphite powder on the wear behavior of Al 7075/Graphite Powder (Gr)/Bagasse ash (BA) hybrid composite. The investigation reveals the effectiveness of incorporation of graphite powder in the composite for gaining wear reduction. The Al 7075 (Aluminium alloy 7075) reinforced with graphite powder and Bagasse ash were investigated. The conventional liquid casting technique was used for the fabrication of composite material and subjected to T6 heat treatment. The reinforcement content was chosen as 1, 3, and 5wt. % of graphite powder to identify its potential for self-lubricating property under dry sliding conditions. Hybrid composite is processed at 1wt% of Gr with 2, 4 and 6wt% of BA. The effect of load on dry sliding wear rate and coefficient of friction performance of Al 7075 casting alloy and its composites was evaluated by using a pin-on-disc with two different loads with constant speed at room temperature. Wear tests were conducted by using pin on disc apparatus to evaluate the tribological behaviour of the composite and to determine the optimum content of graphite powder for its minimum wear rate. The wear rate decreases with addition of graphite powder content and reaches its minimum at 5wt. % graphite. The coefficient of friction decreases with addition of graphite content and was found to be minimum at wt. 5% graphite. The wear properties of the hybrid composites containing graphite exhibited the superior wear-resistance properties.