MULTI-OBJECTIVE OPTIMIZATION OF ROTARY ASSISTED ELECTROCHEMICAL ARC DRILLING (R-ECAD) PROCESS USING GRA

Abstract

Electrochemical Arc Drilling (ECAD) has demonstrated its effectiveness in micro-machining a variety of materials notwithstanding the inherent properties of materials. The increased machining properties of the ECAD method are a result of the inclusion of rotational effect of the working material. Better electrolyte replenishment, effective debris flushing, thin gas layer development, and spark uniformity are all credited with this improvement. Several input factors affect the machining characteristics of ECAD, making it difficult to simultaneously optimize these factors for several objectives. In order to maximise Material Removal Rate (MRR) and minimising Hole Overcut (HOC), this paper focuses on the multi-objective optimization of rotary-assisted ECAD (R-ECAD) input factors. Taguchi's L9 experimental design is used to produce micro-holes, and then Grey Relational Analysis (GRA) is used to perform the multi-objective optimization. The chosen input factors are working material rotation (WR), tool feed rate (FR) and applied voltage (V), whereas the chosen response factors are MRR and HOC. Results indicate that the rotating effect of the working material, which aids in the replenishment of electrolyte and the creation of a stable gas layer surrounding the tool, is notably the most significant input factor. For maximising the MRR and minimising HOC, the GRA-based optimised factors were found to be AIICIIBIII (60 rpm, 40 V, 0.8 mm/min). The responses are greatly improved by 39% as compared to the original machining, as demonstrated by microscopy images obtained during the GRA-based input factor optimization.