Multi-Criteria Decision of W-Powder Mixed Electro Discharge Drilling Parameters using TOPSIS Approach

In this study, Central Composite Design method in combination with Technique for Order of Preference by Similarity to the Ideal Solution has been implemented to estimate the efficiency of multi-objective characteristics for Electrical Discharge Drilling of Inconel 718 using hollow tubular copper electrode. The influence of input process variables such as peak current, pulse-on time and pulse-off time on Material Removal Rate and Surface Roughness have been investigated when Tungsten powder is mixed to the dielectric. Confirmatory test was conducted to verify the predicted results and it showed an improvement of 0.376 g/min and 3.412 using TOPSIS. The suggested settings of process parameters are found to be I-p =10 Amp, T-on = 500 mu s and T-off = 800 from TOPSIS. The drilled surface properties were analyzed by Scanning Electron Microscope and it is observed that that good surface finish was obtained by W-PEDD rather than without the addition of powder to the dielectric fluid.