Parametric study on selective surface modification in EDM using TOPSIS

This study investigates pattern generation by selective surface modification through the analysis of individual machining parameters and Multi Criteria Decision Making (MCDM) method specifically TOPSIS to optimize output parameters based on the weightage of the responses. The results reveal that TWR and MDR rise with I p and T on at any CL of the green compact tool. Similarly, the Ra and ED increase with an increase in I p and T on at any CL setting. With equal weightage for all responses, the optimal setting is at CL 10 ton, I p 3 A, T on 400 µs, resulting in TWR 75.19 mg/min, MDR 6.59 mg/min, Ra 6.10 µm and ED 49.53 µm. Whereas, for weightage of 40% for Ra and ED and 10% for TWR and MDR, the optimal setting is CL 15 ton, I p 2 A, T on 100 µs, with TWR 50.21 mg/min, MDR 1.95 mg/min, Ra 3.67 µm and ED 35.44 µm. Surface characterization via FESEM confirms particle transfer and clustering under low-energy conditions, while random deposition occurs at higher energy levels. EDS and mapping analysis further confirm tool particle transfer, which enhances mechanical and physical properties.