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Modeling and simulation of micro electrical discharge machining process
Micro parts and systems are playing crucial roles in the area of semiconductor, biomedical device, micro fluid devices, automotive, aerospace and so forth. Micro manufacturing is one of the most important technologies in realizing miniaturization. Compared to other micro manufacturing methods, micro-EDM is drawing lots of attention due to its ability to machine complex 3D parts regardless of the hardness of the workpiece material. Micro-EDM is the cumulative result of numerous single discharges; therefore, it is crucial to understand the single discharge material removal process in micro-EDM. However, due to the stochastic nature and complex process mechanism, micro-EDM, including its material removal mechanism, has not been fully understood. Process modeling is an effective way to learn and predict the process. This thesis is focused on the modeling and simulation of the single discharge micro-EDM. Firstly, an analytic method is presented to determine the energy distribution ratio, which is a decisive parameter in the micro-EDM process. This method uses the thermal model and experimentally measured crater geometries to calculate the energy distribution ratio, which is accurate and easy to apply. Secondly, along with the calculated energy distribution ratio and other realistic boundary conditions, a comprehensive thermal model has been studied. The study shows that the simulation results are very close to the experimental measurements after considering the plasma flushing efficiency. Finally, thermal Marangoni effect has been incorporated into the micro-EDM model. Heat transfer and laminar flow have been studied simultaneously. This model is able to simulate the crater formation process which is a big improvement compared to the thermal models. The simulation results prove that Marangoni effect plays an important role in micro-EDM.
Shao, Bai, "Modeling and simulation of micro electrical discharge machining process" (2015). ETD collection for University of Nebraska - Lincoln. AAI3738959.