• Journal of the Korean Society for Precision Engineering
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• v.17 no.7
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• pp.20-27
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• 2000

한국은행의 지식기반산업의 국민 경제적 역할 분석에 따르면, 91년부터 99년까지 지식기반산업의 연평균 성장률은 13.7%로 다른 산업의 4.1%보다 3배 이상 높은 것으로 조사되었다. 그중 항공기, 사무계산 및 회계용 기기, 의약품, 영상 음향 통신장비 등 첨단제조업은 이 기간 중 연평균 20.1% 성장을 기록하였다. 이와 같은 첨단제조업에서는 제품 내 부품의 정밀가공 기술이 필수적이다. 그 중에서도 미세 가공에 대한 관심은 지속적으로 증가하고 있는 추세이다.(중략)

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.69-69
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• 2003

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.83-83
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• 2003

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.61-67
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• 2017

Research into the selection of suitable materials and the development of fast processing methods for press die manufacturing is absolutely necessary to reduce the production time and cost. In particular, knowledge of its heat properties must be considered whendeveloping a long press die. Generally, as the main component materials of press dies, Cr, W low alloy tool steel, high carbon-high chrome steel, high speed steel, etc., are used as thetooling steel for the cold die. Machine tools and wire-cut electric discharge machining are mainly used for processing the press die parts. There are many differences in the machining time and life cycle of die parts depending on the machining process. The parts produced by milling and grinding have a high manufacturing time and cost with a long life cycle, while thosemade by milling and wire-cut discharge machining have areduced manufacturing time and cost,whereastheir die life cycle is reduced. Therefore, in this study, we will discuss amethod of improving the life cycle of the die parts by using heat treatment as a processing method that reduces the manufacturing time and cost. SEM, EDS analysis and the surface roughness analysis of the surface and center of the workpiece are used for analyzing the specimens produced by three machining methods, viz. milling - grinding, milling - wire cut discharge, and milling - wire cut discharge - heat treatment. A method of making die parts having the same life cycle as those produced by milling - grinding is developed with the milling - wire cut discharge - high temperature tempering method.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.246-251
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• 2000

In this paper, Wire electric discharge grinding(WEDG) method for manufacturing the micro shaft was introduced and the machining characteristics was investigated. from the experimental results, it was concluded that high surface integrity could be obtained by use of dielectric fluid spraying method and small capacitive condenser.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.956-959
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• 2001

In die and mould industry, major material such as cemented carbide is broadly used for increasing the life time and decreasing the cost. It is also required the development for the skills of wire-cut electrical discharge machining(WEDM), but the WEDMed surface was found to be worst due to the attached components of wire. Precision machining method like lapping is necessary for obtaining high quality surface. The lapping compound such as Al2O3 and SiC and cast iron lap can be used for lapping process. The components of Cu and Zn were found WEDMed surface of the specimen. As the result, the low quality of precision was obtained and the heat damage layer of the specimen was occurred. The value of surface hardness was deteriorated, and therefore finish process was required.

• Proceedings of the KIEE Conference
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• 2003.04a
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• pp.314-317
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• 2003

높은 정밀도와 고품위 가공이 요구되는 금형제작 등에서 사용되는 고정밀 와이어컷 방전가공기가 고속, 고정밀 가공특성을 갖기 위해서는 무엇보다도 제어와 출력특성이 우수한 고성능의 전원장치가 필요하다. 본 논문에서는 고정밀 와이어컷 방전가공기용 스위칭모드 보조 전원장치로 사용되는 200W 280Vdc 영전압 포워드 컨버터 개발에 대해 기술하고 있다.

• Textile Coloration and Finishing
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• v.7 no.4
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• pp.105-112
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• 1995

방전에 의한 섬유의 표면개질 기술로서, 저온 플라즈마, Sputter Etching 처리에 대해 서술하고 표면개질 효과를 표면장력, ESCA, SEM을 근거로해서 고찰하였다. 더우기 접착성, 염색물의 색채에 미치는 효과에 대해 검토하였다. 섬유의 염색가공에 있어 젖음, 발수, 발유, 접착, 대전방지, 광택, 촉감 등의 표면에 관련하는 기능적 혹은 감각적 특성이 중요한 역할을 하고 있다. 섬유재료의 내부(bulk)의 특성을 살리면서 표면특성의 개질에 의해 한층 기능성을 향상시키는 것은 큰 의미를 가지며, 그와 관련한 표면개질 기술의 연구에 관심을 갖게 되었다. 종래에는 오로지 습식법에 의한 화학약품 처리나 그라프트 공중합 등이 많이 이용되어져 왔으나 습식가공법은 공업적으로는, 다량의 물, 유기용제, 색재, 수지, 계면활성제 등을 사용하기 때문에 피처리물의 건조에 필요한 에너지, 배수처리, 유기용제의 회수 등의 문제가 지적되고 있다. 이들 습식계의 문제점을 극복하는 기술로서 최근은 방전처리나 자외선 처리 등의 건식처리가 많이 연구되어 오고 있다.

• Journal of the Korean Society for Precision Engineering
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• v.27 no.1
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• pp.119-124
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• 2010

This paper addresses the design and fabrication of desktop die-sinking dry electrical discharge machining (EDM) system and its experimental performance analysis. The developed desktop dry EDM machine has the horizontal configuration with the size of $300{\times}200{\times}260mm$. The experimental performance analysis is conducted to investigate the effects of EDM conditions and dielectric gas temperature on the surface roughness of EDMed slots and number of EDM sparks. The experimental results demonstrate that low feed rate and large electrode displacement are good for better surface roughness and more number of EDM sparks. In addition, low temperature of dielectric gas results in better surface roughness.

• Transactions of Materials Processing
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• v.6 no.3
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• pp.192-202
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• 1997

This study presents an effect of number of passes in wire-cut electric discharge machining on fine blanking dies and products. Three part fine blanking dies were produced by the difference of numbers of passes discharge machining. Brake pad was produced, through the die produced like that, the objective of this study is the improvement in surface roughness of die block and punch, life extension of die block, the decrease of second fracture dimensions, the rise of productive.