Modeling and experimental validation of material erosion process in axial ultrasonic vibration-assisted EDM

Ultrasonic vibration-assisted EDM has attracted significant attention due to its ability to obtain better machining quality. In this paper, the inter-electrode energy distribution relationship of axial ultrasonic vibration assisted EDM (Ax-UEDM) was analyzed. Combined with heat transfer, a vibro-electro-thermal model was developed for describing the material erosion process. The model reveals and presents a dynamic correlation between ultrasonic energy, electrical energy, thermal energy and surface topography. By controlling the ultrasonic energy or adjusting the parameters, the surface topography can be simulated and tuned. As the ultrasonic vibration amplitude increases from 5µm to 15µm, the energy acting on the cathode decreases by 2.4–20.8% compared to EDM. According to the experimental results, it resulted in a reduction of surface crater radius by 6.25-30%. When the ultrasonic vibration amplitude is 15 µm, the surface roughness is reduced by 20.8%. This study reveals the mechanism of matching and transforming multiple energy fields (ultrasonic energy, electrical energy, and thermal energy), and realizes the micro-regulation of composite energy fields. Provides the necessary theoretical basis for process improvement in Ax-UEDM.