Investigations on the Machinability of Al/SiC/RHA Hybrid Metal Matrix Composites

Hybrid aluminum metal matrix composites (MMC's) are the emerging materials that gain superior properties in terms of hardness, specific strength, mechanical and physical properties in relation to native metals. These difficult to cut MMC's are more suited as the state-of-the-art materials giving engineers an opportunity to tailor the material properties in order to adapt for the future requirements. Machining MMC's is a challenging task and it is even more difficult to machine a hybrid metal matrix composite due to the inclusion of two or more reinforcement particles. Hence, the present work aims in predicting and comparing the experimental data while machining aluminum reinforced with silicon carbide (SiC) and rice husk ash (RHA) particulates. Varying the machining parameters like cutting speed, feed and depth of cut the surface quality, cutting forces and flank wear progression are analyzed. From the outcomes, it is distinguished that, finer surface finish is acknowledged at higher cutting speeds where uninterrupted chips with-out built up edge (BUE) is formed. The cutting force components were found to decrease with increase in cutting speed and increase with varying feed and depth of cut. It was further noticed that the cutting force components decrease with the increase in the % of reinforcement. For the purpose of validation of the cutting force components, Al/6%SiC/6%RHA MMC is selected and validated theoretically with analytical equations. Flank wear tends to increase with cutting speed, feed and depth of cut. Abrasion mechanism is found to be the dominant factor that gives pronounced flank wear. The total volume loss in terms of a quadrature with two body and three body abrasive mechanisms is considered to approve the progression of flank wear and the same was validated with analytical equations.