*3.2.4 Ming's model*

Ming et al. [12] constructed a thermal model of single-spark EDM process based on the finite element method, considering the variable heat distribution factor for the workpiece, latent heat and plasma flushing efficiency (PFE), to predict material removal rate. They derived an equation of heat distribution factor for the workpiece from experimental data presented by Singh [17] considering the dissimilarity of machining conditions, work-tool materials and mainly the thermal conductivity of the workpiece by assuming the proportionality coefficient.
