Study on mechanism and surface topography of ultrasonic powder mixing–assisted EDM.

In this paper, the effects of ultrasonic vibration and powder mixed on Electrical Discharge Machining (EDM) are investigated. Based on the heat transfer theory, an ultrasonic powder mixed EDM (US-PMEDM) heat transfer model combining ultrasonic vibration and powder mixed characteristics is established, and the heat transfer model carries out a transient thermodynamic simulation for the process of removing the material during the EDM process, and through the experimental and simulation analysis of four kinds of EDM, powder mixed EDM (PMEDM), ultrasonic (UEDM), and US-PMEDM, the accuracy of the simulation is verified. The accuracy of the simulation was verified by observing the surface morphology after machining. The material removal process was analyzed under different machining methods and different concentrations of powder mixed particles. Under the processing conditions of fixed processing current of 2A, ultrasonic amplitude of 5 µm, and powder concentration of 2g/L, the material removal rate (MRR) of the PMEDM method was increased by about 26.3% and the surface roughness (SR) was reduced by 7.78% compared with that of the EDM method, and the material removal rate of the US-PMEDM method was increased by about 49.4% and the surface roughness was increased by 4.05% compared with that of the EDM method. The surface quality can be improved by adding powder mixing, and the surface quality of powder mixing is better than that of ultrasonic vibration. [ABSTRACT FROM AUTHOR]