• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.258-258
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• 2004

전해 가공은 공작물의 기계적 특성과 무관하게, 빠른 속도로 가공할 수 있는 장점이 있으나, 가공 간극이 비교적 넓어 초정밀 가공에는 널리 적용되지 못했다. 최근 Schuster는 초단 펄스를 이용한 전해 가공으로 가공 간극을 수 $\mu\textrm{m}$ 까지 줄일 수 있고 미세 3차원 구조물의 정밀가공에 초단 펄스를 적용할 수 있음을 보였다. 본 논문에서는 초단 펄스를 이용한 미세 흠의 와이어 전해 가공에 대하여 연구하였다. 전극으로는 지름 10$\mu\textrm{m}$ 백금 와이어를 사용하였으며 공작물은 스테인리스 스틸을 사용하였다.(중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.145-145
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• 2004

미세 전극을 이용한 미세 방전 가공이나, 미세 전해 가공은 다른 가공 방법에 비해 상대적으로 가공속도가 느리고 전극을 이송시키면서 한 번에 한 개의 형상 가공을 하므로 생산성이 떨어지는 단점이 있다. 하지만 다수의 미세 전극을 이용하여 다수의 형상을 동시에 가공함으로써 이러한 단점을 극복할 수 있다. 본 논문에서는 미세 역방전(micro reverse electro-discharge machining, micro REDM)을 이용하여 한 개의 벌크 전극에 여러 개의 미세 전극을 제작한 뒤 전해 가공을 이용하여 다수의 구멍을 동시에 가공할 수 있는 프로세스에 대하여 연구하였다.(중략)

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.3
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• pp.370-375
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• 2010

Tungsten carbide microshaft is used as micro punch, electrode of micro electro discharge machining, and micro tool because of its high hardness and rigidity. In this research, tungsten carbide microshaft was fabricated using electrochemical machining. $H_2SO_4$ solution was used as the electrolyte because it can dissolve tungsten carbide and cobalt simultaneously. Experimentally studied were the effects of electrolyte concentration, machining time, and machining voltage on material removal rate and the shape of the microshaft. To eliminate the effects of bubbles and metal corrosion layer on microshaft shape, the machining was performed below the electrolysis voltage. Three step electrochemical process was suggested to fabricate the straight tungsten carbide microshaft. As a result, a straight tungsten carbide microshaft of $30{\mu}m$ in diameter and $500{\mu}m$ in length was obtained through the proposed three step electrochemical process.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.131-135
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• 1993

오늘날 전자산업, 광학기계,미세노즐 및 오리피스, 정밀공구,게이지, 고밀도 PCB 기판등 각종 산업에서 미세구멍 가공기술이 요구되고 있다. 이러한 구멍 가공에 사용될 수 있는 기술로는 드릴 가공의 기계적 가공방식 이외에 레이져가공,전자빔가공, 방전가공등의 열적가공방식과 전해가공,전해연마,화학부식의 화학적가공 방식이 있겠으나 생산성, 가공표면의 정도, 심혈가공의 어려움 등의 이유로 미세드릴을 이용한 기계적인 가공방법이 선호되고 있다. 본 연구에서는 미세구멍/가공시 가공토크에 미치는 중요 변수들의 영향을 실험을 통하여 조사하여 높은 절삭성을 발휘하는 동시에 공구의 파손도 피할 수 있는 조건을 제시하였다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2014.11a
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• pp.142-144
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• 2014

전해가공(ECM)과 방전가공(EDM) 공정은 독특한 출력이 가능한 두 가지 이점이 있다. 방전가공과 전해가공은 보다 효과적이면서 거대하고, 미세한 나노 특성과 재료 가공의 정확한 3차원 복잡 형상 가공의 대안을 제공해준다. 본고에서는 학술적이고 산업적인 연구와 응용에 있어서 기예를 반영한 전해가공과 방전가공 공정의 기술적인 진전을 간략히 기술하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.245-249
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• 2002

Tungsten carbide microshaft is used as various micro-tools in MEMS because it has high hardness and good rigidity. In this study, experiments were performed to produce tungsten carbide microshaft using electrochemical machining. $H_2SO_4$solution was used as electrolyte because it can dissolve tungsten and cobalt simultaneously. Optimal electrolyte concentration and machining voltage satisfying uniform shape and large MRR of workpiece were found. For one-step machining, the immersion depth over 1 mm was selected for avoidance of concentration of electric charge at the tip of the microshaft. The limit diameter with good straightness was shown and an empirical formula for WC-microshaft machining was suggested. By controlling the various machining parameters, a straight microshaft with 30 $\mu\textrm{m}$ diameter, over 1 mm length and under 0.5$^{\circ}$ taper angle was obtained.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.6
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• pp.105-112
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• 2007

Tungsten wire micro electrochemical machining (W-wire micro ECM) with ultra-short pulses enables precise micro machining of metal. In wire micro ECM, platinum wire has been used because it is electrochemically stable. However, the micro metal wire with low strength is easily deformed by hydrogen bubbles which are generated during the machining. The wire deformation decreases the machining accuracy. To reduce the influence of hydrogen bubbles, in this paper, the use of tungsten wire was investigated. To improve machining accuracy, suitable pulse conditions which affect generation of bubbles were also investigated. The tungsten wire micro ECM can be applied to the fabrication of various shapes. Using this method, various micro-parts and shapes were fabricated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.999-1002
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• 2002

In this research, the mechanism of micro-ECM was investigated with potentiodynamic method and the optimal condition for micro-ECM was selected by voltage-current-time curve with potentiostatic method. From the experimental result. it was confirmed that anodic voltage curve could be used very effectively for determining the optimal condition of micro-ECM, and the micro part which has extremely fine surface could be fabricated by use of micro-ECM with point electrode method.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.906-909
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• 2000

To improve dimension accuracy and make very small parts are one of the major purpose on the electrochemical micromachining. This paper introduce a small machine tool by using the point electrode. That has a data acquisition system for gathering applied electric condition between the gap. Point electrode on this system was made by this method as well. It was found that variable phenomena occurred through the acquired V-I curve on the process.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.139-140
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• 2010