In this study, an electrolytic micro-machining tester is employed to investigate the effects of supply voltage and initial machining position on the geometry of the tungsten needle using the single-point and the reciprocating methods. The tungsten needle to be electrolyzed is dipped in an aqueous electrolyte of 2wt % sodium hydroxide as the anode, and the stainless steel needle with a diameter of 100 £gm as the cathode, and the electrode gap is set to be 10 £gm.
Experimental results show that it is difficult to control the diameter of the tungsten needle because the reduction rate of its diameter is quite fast and the bubbles are generated violently to cause the breakage of the tungsten needle at the higher supply voltage. At the lower supply voltage, the tungsten needle can be machined to a finer scale, but it takes a long machining time.
Under the single-point machining condition, it can be used to manufacture a short, uniform, and smooth tungsten needle with the diameter of 9 £gm at the supply voltage of 12V and the initial machining position of 75 £gm. Under the reciprocating machining condition, a long uniform micro-cylinder tungsten needle can be manufactured, but its surface becomes rough slightly at the supply voltage of 4V and the initial machining position in the range between -50 and 0 £gm. A tungsten needle with the aspect ratio of 30 and the diameter of 9 £gm can be manufactured using the following process: the machining time of 24 min at the supply voltage of 4V, and then the machining time of 28 min at the supply voltage of 2V.
Key words¡Gtungsten needle, sodium hydroxide
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0909108-154323 |
| Date | 09 September 2008 |
| Creators | Wang, Yong-siang |
| Contributors | Lin, Jen-Fin, Lee, Rong-Tsong, Jeng, Yeau-Ren, Chiou, Yuang-Cherng |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0909108-154323 |
| Rights | campus_withheld, Copyright information available at source archive |
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