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Abstract: Based on the principle of electrochemical reactions, the characteristic and mechanism of nanosecond pulses electro- chemical micro-machining are investigated and the theoretical model of micro-electrochemical machining (ECM)
is founded. The affections of electrolyte concentration, electrodes gap
and pulse parameters on the result of electrochemical micro-machining are discussed. The practical electrochemical machining system is developed. It consists of micro-machining equipment, nanosecond pulse power supply, electrolyte circulating system, movement control component and process monitoring component.
The effects of pulse on-time and voltage on the side gap of electrodes
are investigated with experiments. The result of experiments show that decreasing pulse duration and voltage can enhance the localization and improve electrochemical micro- machining accuracy. On the self-developed equipment, tool electrode and workpiece are sequentially machining in electro- chemical method. Inter-electrode gap is restrained less than 5 μm. A crisscross micro-groove with 30 µm width and the micro-structure with size 20 μm×30 μm×30 μm is produced. The influence of starting point upon forming precision is analyzed. The experimental results prove that micro-ECM can well meet the demand of micro machining.
Key words: Electrochemical micro-machining
Nanosecond pulses Inter-electrodes gap
Machining accuracy
CLC No: TG662
航空科学基金(04H52055)和南京航空航天大学博士学位论文创新与创优基金(BCXJ04-09)资助项目. Received 20060208, received in revised form 20060812
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