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The manufacturing of surface microstructure is an important means for the modification of surface characteristics of parts. Through-mask electrochemical manufacturing is also an efficient way to fabricate surface microstructures. Nevertheless, in cases where the through-mask electrochemical manufacturing is used for the fabrication of microstructures, many experiments are required to control the cross-section morphology of the microstructures. Furthermore, there is a lack of quantitative analysis of the impact of key variables on the process. In this paper, using numerical simulations based on the geometric structure of mask feature, we analyze the effects of the aspect ratio of mask feature and the gap between cathode to mask on electrochemical micromachining. We further investigate the influence laws of the mask feature’s geometric structure on the anode current density distribution and forming process. A critical value of "0.8" is also determined for aspect ratio of mask feature which is closely related to the anode current density distribution and forming process. The through-mask electrochemical micromachining experiments confirm the effect laws of the geometric structure of the mask feature. And the critical value (0.8) of aspect ratio can be used as the basis for selecting mask feature.

To solve the problem of the nonuniform distribution of temperature and electrolytic products in the electrolyte flow field during through-mask electrochemical micromachining, the use of a rotating cathode with surface structures is proposed. The rotation of the cathode increases the efficiency of heat and mass transfer by the electrolyte flow. Simulations are performed to analyze the influence of the type of surface structure, the number of surface structures, and the rotational speed of the cathode on the electrolyte flow field. The results show that the use of a rotating cathode with surface structures significantly improves the mass transfer efficiency of the electrolyte flow field in comparison with a conventional cathode structure, and, in particular, a grooved rotating cathode can increase the outlet flow velocity by about 23%. An experimental demonstration of micropit array processing shows that the use of a grooved rotating cathode increases the mass transfer efficiency by 34% and the processing efficiency by nearly 40% compared with a smooth-surfaced rotating cathode. The grooved rotating cathode also gives the highest machining accuracy. Using this cathode, a uniform micropit array with an average micropit diameter of 201.83 μm, a diameter standard deviation of 3.49 μm, and a depth standard deviation of 0.87 μm is processed.

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