Optimum Machining Parameters for Al 7075 Hybrid Metal Matrix Composites Using Multi-objective Optimization Technique and the Modified Taguchi Approach

Lightweight composite materials with improved mechanical properties are widely used in industries. There is a need to obtain optimum machining parameters of such hybrid composites. This paper uses reliable multi-objective optimization technique and modified Taguchi approach to determine optimal machining parameters such as speed ( NS) varying from 1000 rpm to 1500 rpm, feed rate (FR) from 0.10 mm/rev to 0.20 mm/rev, depth-of-cut (D-C) varied from 0.5 mm to 1.5 mm and percentage reinforcement (R%) varied from 2 to 6 to achieve maximum material removal rate (MRR) and minimum surface roughness (SR) of the hybrid composites. The hybrid metal matrix composite (i.e., Al 7075 reinforced with B4C and rice husk ash, RHA) is manufactured using a stir casting technique. A set of optimum machining parameters is found to be N-S = 1500 rpm, F-R = 0.1 mm/rev, D-C = 1.5 mm and R% = 2. Empirical relationship for MRR and SR are developed in terms of the machining parameters. A confirmatory experiment is performed and the optimal solution is validated.