Abstract
Stray current causes undesired material dissolution in micro-electrochemical machining (micro-ECM). The reduction of stray corrosion, caused by stray current, continues to be a major challenge for accuracy improvement. To limit the distribution of stray current, a shunt-assisted silicon electrode, with an auxiliary anode sharing stray current, is proposed in this study. The auxiliary anode is arranged outside the insulating layer of the sidewall-insulated electrode. It is proved in simulation that the auxiliary anode can help reduce the average material removal rate on the machined surface by 55% and improve processing accuracy. A fabrication process of shunt-assisted silicon electrode by bulk silicon process and thin film deposition process are presented. Microgrooves and holes are machined in ECM experiments. The angle between each side-wall and the vertical plane is less than 10 deg. The gap between the sidewall of the machined structures and electrode-outer-contour is about 30 lm66 lm for the grooves and 45 lm610 lm for the holes. These long-term experiments and consistent processing results show the shunt-assisted electrode is reliable in ECM process. But due to the stray corrosion induced by DC power supply and conservative feed method, the effect of the shunt-assisted silicon electrode in inhibiting stray corrosion is not significant. In the future, a micro-ECM system with novel power supply and active control methodologies is expected to better utilize the effect of the shunt-assisted silicon electrode.
Original language | English |
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Article number | 024502 |
Journal | Journal of Micro and Nano-Manufacturing |
Volume | 11 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1 Jun 2023 |
Keywords
- a shunt-assisted silicon electrode
- micro-ECM
- stray corrosion