| dc.description.abstract | In the Through-Mask Electrochemical Micro-machining (TMEMM), one tool can be used to machine work-pieces of different shapes or patterns if different masks are provided. The designing time and cost for tools is largely reduced. The electrolyte recycle doesn’t have problem and the process is very fast. Therefore, TMEMM is suitable in machining arrays of holes in a large area.
The process of TMEMM involves complex physical phenomena. Nowadays, the simulation on TMEMM is primarily restricted in the influence of electric field, plus the experimental verification. In this study, the 3D electric field is implemented with the thermal and flow fields and solved by the finite element method. The effects of flow directions, applied voltages, and electrolyte flow rates on the machined shape are investigated. A modified through mask is proposed and simulated, and comparisons of the machining profiles by traditional and modified masks are made.
Results show that the average depth, flatness, average radius and roundness are all increased as the applied voltage is increased. The roundness in the forward flow is better than that in the lateral flow. As the flow rate is faster, the average depth, flatness and average radius will be decreased. The roundness is at its best at flow rate of 0.05m/s in the lateral flow and 0.5m/s in the forward flow. In the modified TMEMM process, under the same applied voltage, the flatness and average radius in the forward flow are better than that in the lateral flow, while the average depth and roundness are worse. Compared with the traditional TMEMM, the modified TMEMM can yield better average depth, however the shadow effect and small inter electrode gap will let its flatness becomes worse. The modified TMEMM with lateral flow results in better roundness than the traditional EMEMM does. | en_US |