Optimization of Machining Parameters for Surface-roughness and Precision in EDM Using Response Surface Method

Abstract

The quality of the components of the machining process is determined by the value of surface roughness and dimensional precision. This study uses the Central Composite Design experimental method on the Response Surface Method. To determine the variation of experiments, three factors and three levels were used, the specimens used were mild steel with a total of 20 experimental variations in the EDM (Electrical Discharge Machining) machining process. Then the surface roughness and dimensional precision are tested. Optimization is done by the method of non-linear programming, where the first response is surface roughness and the second response is the precision of the dimensions of the length of the machining process. The results of the analysis show that the strong current influences the surface roughness and dimensional precision. While on time and off time do not really affect the surface roughness or precision dimensions. Optimization with non-linear programming techniques produces a minimum surface roughness of 3.805880 (µm) and dimensional precision of the maximum machining time is 175.2290 (minutes) with a current adjustment of 3 (Amperes), on-time 100 (µs), and off-time 20 (µs).