Investigation on the geometric evolution of microstructures in EDM with a composite laminated electrode. (20th May 2021) - Jiang, Kai
Abstract: Based on the difference in the wear rate of different materials in electrical discharge machining (EDM), wear-variation EDM (WV-EDM) takes full advantage of the electrode wear, which has always been considered as a headache in past research work, to continuously mass fabricate surface microstructures. However, the mechanism of the electrode wear in WV-EDM is not clear, which means that the optimization of the processing parameters and the law of the electrode wear are based on large numbers of experiments, resulting in a lot of waste of experimental materials, equipment, and human resources. In order to achieve green, healthy production and save resources, it is urgent to minimize the amount of EDM experiments on the premises of ensuring research quality and production demand. In view of the variety of electrode materials, this paper studies differences in material removal by single-pulse EDM and proposes a discharge erosion strategy of EDM with composite laminated electrodes (CLEs). After that, a two-dimensional simulation model was established to investigate and predict the geometric evolution of the electrode and workpiece during EDM. Finally, the accuracy of the model was evaluated by comparing profiles derived from simulations and experiments. The statistically relative error of the simulation model was less than 5%, indicating that the simulation model could provide theoretical guidance for the sustainable mass production of surface microstructures by WV-EDM, thereby greatly reducing the number of experiments, saving resources, and improving the experimental efficiency. Highlights: The proportion of energy consumed by vaporizing and melting is investigated. The discharge crater radius and discharge distance of different materials are studied. The discharge erosion strategy of the composite laminated electrode is developed. The simulation model of EDM with composite laminated electrode is established. The profile evolution of the microstructures on the workpiece in EDM is predicted.