Experimental study on electrodischarge machining in water of D2 tool steel using two different electrode materials

Abstract Water as the dielectric in electrodischarge machining (EDM) is an alternative to traditional hydrocarbon oil to promote a better working environment from the perspective of health and safety, as it does not decompose and release harmful vapours (CO and CH4). In order to enhance the understanding of water as a dielectric, this paper presents an investigation of the EDM performance on D2 tool steel using water as the dielectric. The experiment was carried out using different types of water (tap water, deionized water, and mixtures of tap and deionized water) and two different electrode materials: brass and bronze. The results have shown that the greatest EDM performance, which corresponds to the maximum material removal rate (MRR) and the minimum tool wear rate (TWR), is achieved with a mixture of 75 per cent tap water and 25 per cent deionized water as the dielectric, while deionized water resulted in the worst performance. Finally, a case study of a forming die with a complex shape was machined using the results obtained in this investigation.