Analytical Simulation of Random Textures Generated in Electrical Discharge Texturing

Abstract

Textured functional surfaces are finding applications in the fields of bioengineering, surface energy, hydrodynamics, lubrication, and optics. Electrical discharge machining (EDM), which is normally used to generate smoother surface finish on various automotive components and toolings, can also generate surfaces of rough finish, a desirable characteristic for texturing purposes. There is a lack of modeling efforts to predict the surface textures obtained under various EDM operating conditions. The aim of the current work is to capture the physics of the electrical discharge texturing (EDT) on a surface assuming random generation of multiple sparks with respect to (i) space, (ii) time, and (iii) energy. A uniform heat disk assumption is taken for each individual spark. The three-dimensional (3D) texture generated is utilized to evaluate a 3D roughness parameter namely arithmetic mean height, Sa. Surface textures obtained from the model are validated against experimentally obtained ones by comparison of distribution of Ra values taken along parallel sections along the surface. It was found that the distribution of simulated Ra values agrees with that of experimental Ra values.