Experimental investigations into the effect of process parameters and nano-powder (Fe2O3) on material removal rate during Micro-EDM of Co-Cr-Mo

Cobalt-base alloys are normally applied to materials that require wear, corrosion, and heat resistance. Today, the alloy of cobalt–chromium–molybdenum (Co–Cr–Mo) is employed in aerospace and medical fields. Through the thermal erosion process of Electrical Discharge Machining (EDM), an electrically-produced spark vaporizes materials that are electrically conductive. This paper examines the viability of improvement of material removal rate in the micro-electric discharge machining of cobalt chromium molybdenum (Co-Cr-Mo) using Fe2O3 nanopowder-mixed dielectric fluid. For the purpose of this research, a copper electrode with 300μm diameter and positive polarity was utilized. The performance measures of the machining process were investigated regarding the material removal rate (MRR). For analysis of EDM of the CoCrMo, response surface methodology (RSM) was employed. Two concentrations of nanopowder were added to dielectric (2g/land 4g/l). Findings showed that if Iron oxide nanopowders (Fe2O3) exists in the dielectric, MRRcan be significantly improved. Amongst the two concentrations of powder-mixed micro-EDM, 2 g/l of nanopowder provided higher MRR in comparison with 4g/l and without powder cases.