Taguchi’s L₉ orthogonal array has been effectively used to study the effect of process parameters such as voltage, feed rate and electrolyte concentration on material removal rate in context of two different types of electrolyte, namely, aqueous NaCl solution and CuSO₄ mixed aqueous NaCl solution. The results indicated that Cu²⁺ ions formed due to electrochemical reactions prevent the oxidation of Fe²⁺ to Fe³⁺ and catalyze the anodic dissolution of iron during machining. The experimental results were analyzed using analysis of variance method to investigate the significance and percentage contribution of individual process parameters on performance characteristics.