Analysis of the Surface Roughness Characteristics of EDMed Components Using GRA Method

Abstract

The mechanical efficiency of two mating surfaces is significantly affected by the values of their surface roughness, which is also related to increased friction and their tribological performance. In this paper, during generation of holes on D3 tool steel material, the machining capability of an electrical discharge machining (EDM) process is investigated, while considering pulse-on time, pulse-off time and peak current as the controllable parameters. Various surface roughness characteristics, like Rt, Ra, Rq, Rsk, Rz, Rku, Rk, Mr1 and Mr2 are contemplated here as the process outputs because achievement of better tribological properties with low wear significantly depends on those responses. During the experimental trials, pulse-on time is varied from 90 to 250 μs, whereas, the values of pulse-off time and peak current are altered from 45 to 150 μs and 14 to 22 A respectively. Multi-objective optimization of the considered EDM process is accomplished using grey relational analysis (GRA) technique. Confirmation experiment is also carried out to confirm the betterness of the optimal parametric intermix for the said EDM process. It is observed that almost all the surface roughness properties of the EDMed components are mainly influenced by pulse-on time, followed by peak current.