STUDY THE EFFECT OF DIFFERENT DIELECTRIC ON MATERIAL REMOVAL RATE, ELECTRODE WEAR RATE AND SURFACE ROUGHNESS IN EDM PROCESS

Abstract

Electrical Discharge Machining (EDM) is one of the earliest non -traditional machining methods for making high precision and difficult shaped part. EDM process is based on thermo-electric energy between the workpiece and an electrode. Dielectrics and electrical parameters were considered as the main factors for EDM performance. In this paper, the influence of current (A) and pulse-on-time (μs) were evaluated for performance measures using petroleum and vegetable oil as dielectric. A comparison was performed for both dielectrics in terms of material removal rate (MRR), electrode wear rate (EWR) and surface roughness (SR) of stainless steel 316L alloy with copper electrode. The results show that the performance of the newly suggested vegetable oil is better than petroleum, for material removal rate, electrode wear and surface roughness. Results indicated that current is the most important influencing parameter for MRR, EWR and SR. Under the effect of increased current on vegetable oil and petroleum, there was higher MRR and lower EWR, SR; however, same effect has been observed with higher values of pulse-on-time. The MRR in petroleum was 87% lower than that in vegetable oil, whereas the EWR was approximately 58% higher than that in vegetable oil. In addition petroleum produced 49% higher SR than vegetable oil.