How is metal removal rate (MRR) measured and maximized when using graphite EDM electrodes?

Metal removal rate is typically expressed as cubic millimeters per hour or cubic inches per hour, although it can be realistically evaluated in terms of dollars earned per hour. Achieving an efficient MRR depends not only on machine power settings, but also on the direct energy dissipated during the EDM spark erosion process. While graphite is generally far more efficient than metallic electrodes, metal removal rates vary substantially across different graphite grades and classifications. Maximum MRR is achieved when the electrode material, workpiece metal, and specific machining parameters are correctly paired.