Micro-electrical discharge machining of reaction-bonded silicon carbide (RB-SiC)

In this work, a series of micro EDM experiments were carried out to investigate the effect of electrode shape, electrode diameter, and the rotation of electrode on the form accuracy, dimensional accuracy and surface properties of RB-SiC. It was found that with the rotating electrode, better form accuracy, surface finish, and dimensional accuracy can be obtained. Spherical electrodes were able to produce better cross-sectional profiles of micro holes compared to cylindrical electrodes. Hole expansion was found to decrease when the cylindrical electrode diameter increases, while the radius of spherical electrode does not have a linear relationship with the overcut.