Surface Response Methodology Approach for Multi-Objective Optimization During Electrochemical Grinding of Al2O3/Al Interpenetrating Phase Composite

1. Introduction

Rapid globalization has drastically changed the dynamics of the manufacturing industries across the globe which necessitates the use of alternative and concurrently superior materials for several applications commensurable with the deliberated use. In order to persevere in this competitive business environment industries are enduring several modifications by reorienting the traditional manufacturing process to non-traditional manufacturing process. In order to survive with the changes application of these evolving manufacturing techniques along with the contemporary materials are becoming popular gradually. Electrochemical Grinding (ECG) process is an amalgamation of electrochemical dissolution and mechanical abrasion which is one such very widely used non-conventional machining processes for machining complicated shapes in high strength electro-conductive materials, difficult-to-machine alloys, fragile, hardened and also heat sensitive parts (El-Hoffy, 2005). In ECG electrolyte is pumped in a small gap between the cathode grinding wheel and anode work piece. Direct current is passed through the system which helps in the dissolution of electrolyte solution. The major parameters influencing ECG process are Electrolyte Concentration (C), Voltage (V), Depth of cut (D) Flow rate (F), physical properties of the work piece, type of abrasive in the wheel, grain size of the abrasive particle, speed of the grinding wheel etc. (Reddy et al., 1998). As the material removal process is done by electrochemical dissolution of work material, the machined surfaces are free from residual stress and burr, thereby eliminating rejection caused by stress and cracks (Kaldos,1974). In this machining process there is no need of time consuming secondary operations.

Some of the past research works is presented here. Qu et al. (2015) prolong the wheel life in ECG while machining Inconel 718, by replacing the electrodeposited diamond wheel by the brazed diamond wheel. Senthilkumar et al. (2011) has studied on the process optimization of the machining parameter in electrochemical grinding for contradictory result by employing non-dominated sorting genetic algorithm-II (NSGA-II) for multi-objective optimization. Geva et al. (1976) has experimented on electrochemical surface parameters in ECG process and proposed a suitable process mechanism based on the output results. Molla and Manna (2013) has optimized the machining parameter of Al/(Al₂O₃+ZrO₂) while machining in electrochemical grinding, and they find out that the roughness (R_a and R_t) are lesser at moderated grinding wheel speed. Bhandari and Shukla (2015) have studied on the optimization procedure of the control parameter of electrochemical grinding by using Particle Swarm Optimization Technique. Goswami et al. (2008) have investigate the effect of the process parameters while machining Al₂O₃/Al Interpenetrating Phase Composite material using ECG process and beside that they find out the effect of different kind of electrolytes and degree of reduction in this course and finally they compare the conventional grinding with electrochemical grinding of this material. Roy et al. (2007) experimentally studied using statistical procedure was made to evaluate the effect of the voltage on the surface finish of P-20 material. Puri and Banerjee (2013) comprehensively evaluated the influence of voltage and cutting speed on ECG while machining composite carbide inserts material. Levinger and Malkin (1979) have investigated on ECG of WC-Co cemented carbides and find out that electrochemical dissolution into the cobalt phase occurs initially at much faster rate than into the carbide phase and also their experimental result explains the interaction between the electrochemical and mechanical process. Kaczmarek and Zachwieja (1966) have investigated on the MRR by ECG of cutting tool materials and find out that MRR is depend on electrochemical solution as well as the grainsize of the grinding wheel. Atkinson (2007) has experimentally exhibits how surface hardness changes after machining AISI 01 tool steel in different regimes.