| Summary: | 碩士 === 國立中央大學 === 機械工程學系 === 101 === The purpose of present thesis is to fabricate a thread-like micro-pin, which can be used as the electrode tool in the electrochemical micro-drilling and enhances the removal of dissolved metal, expulsion of producing gases, and recirculation of the electrolyte. The formation mechanism of thread is specially forcused. The influence of working parameters, such as applied voltage, machining time, anode rotating speed, and multiple-step machining, on the fabrication thread-like micro-pin is investigated.
Experimental results show that the I-V curves under various anode rotating speeds are different. The limiting current and the corresponding voltage increase as the anode rotating speed increases. The thread can be fabricated under the condition of limiting current, where the electrochemical mechanism is polishing. However, the formed thread will be dimished gradually as the machining proceeds. A multi-step machining method can be applied to enhance the depth of thread. That is, as the thread is formed to a certain stage, a lower voltage is applied such that the electrochemical mechanism is switched to itching, instead of polishing. The thread will thus become deeper. A optimal thread-like micro-pin can be obtained under applied voltage of 2.6 V, machining time of 2 minutes, and anode rotating speed of 4000 rpm.
|
|---|
