Multi performance optimization of electrochemical micro-machining process surface related parameters on machining Inconel 718 using Taguchi-grey relational analysis

Due to several merits such as higher machining rate and high machining accuracy, electrochemical micromachining (ECMM) is used to machine high strength materials with complex shapes. In this experimental investigation, Inconel 718 specimens have been machined with brass electrode of 500 pm diameter using ECMM. Since electrochemical micromachining involves many responses, Taguchi method along cannot give to find out unique optimum parameter combination of the ECMM process. Therefore, an attempt has been made in the present study to identify the optimum combination of process parameter using grey relational analysis with Taguchi method. The experimental investigation of the process has been conducted with input process parameters such as applied voltage, electrolyte concentration, micro-tool feed rate and duty ratio on material removal rate (MRR), surface roughness (SR) and overcut (OC) with different process level using two electrolytes such as sodium chloride (NaCI) and sodium nitrate (NaNO3). From the experimental results, it has been found that micro-tool feed rate is most influencing nature parameter for NaCI and applied voltage is most influencing nature parameter for NaNO3 in ECMM process.