Experimental investigation of machining rate, geometrical accuracy and optimization of machining parameters in electrochemical micromachining of stainless steel 304

This study investigates the influence of sodium chloride-based electrolytes on the electrochemical micromachining (ECMM) process of stainless steel SS304, a material widely used in the automotive industry. The research focuses on two electrolyte combinations: Tamarind + NaCl and Succinic acid + NaCl, and their effects on material removal rate (MRR), overcut, and circularity. Using the Taguchi design of experiments, the study examines the impact of process parameters such as applied voltage, electrolytic concentration, frequency, and duty cycle on machining characteristics. The results demonstrate that the Tamarind + NaCl electrolyte combination achieves the highest MRR, with an approximate increase of 29.24% compared to the Succinic acid + NaCl combination. Additionally, the Tamarind + NaCl combination exhibits a 47.45% improvement in overcut and superior machining performance in terms of circularity error. Multi-response optimization techniques, including Grey Relational Analysis (GRA) and Desirability Function Analysis (DFA), are employed to identify optimal parameter combinations. GRA suggests that a voltage of 12 V, an electrolyte concentration of 20% (10 + 10 g/L), a pulse frequency of 80 Hz, and a duty cycle of 50% result in the highest MRR and minimum overcut and circularity error for the Tamarind + NaCl combination. DFA is used to optimize multiple quality indicators simultaneously, minimizing or maximizing responses within the specified range of process parameters. The findings emphasize the importance of electrolyte selection and process parameter optimization in enhancing the efficiency and effectiveness of ECMM processes for machining high-strength materials like stainless steel SS304, with significant implications for various industrial applications, particularly in the automotive sector.