Numerical Modelling of Surface Quality in EDM Processes

Electro-discharge machining (EDM) is a non-conventional cutting technology widely applied to generate mechanical parts with a complex geometry. In order to describe the thermo-physical phenomena involved in this process and estimate the expected results for different cutting conditions, not only the experimental observation but also the numerical modelling is convenient. In the present work, a simplified numerical model is proposed to analyse the surface finish in penetration EDM with a minimized time for numerical computation. This model is focused on prediction of the material removal and surface irregularities on the workpiece material, from the heat transfer and cutting temperatures provoked by the successive sparks. The changes originated on the topography of machined surface can be properly predicted as a function of cutting time by the proposed model. The numerical predictions are compared with experimental results for the same cutting conditions, and a good agreement is found between both results.