• 자원리싸이클링
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• 제18권1호
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• pp.52-57
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• 2009

비철금속은 종류가 많아서 비철금속 전반에 걸친 리싸이클링 현황을 파악하기에는 분량이 너무 방대하기 때문에 아직까지 개별 금속에 대해서는 비철 금속 리싸이클링 현황을 조사하긴 했지만 전반적으로 조사 발표된 적은 없다. 본 고에서는 상용 비철금속인 동, 연, 아연, 알루미늄, 니켈 및 마그네슘에 대하여 최근 몇 년간의 국내 수요, 생산량과 스크랩에 대한 리싸이클링 현황을 조사, 발표한다.

• 자원리싸이클링
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• 제22권6호
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• pp.81-86
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• 2013

비철금속은 종류가 많아서 비철금속 전반에 걸친 리싸이클링 현황을 파악하기에는 분량이 너무 방대하기 때문에 개별 금속에 대해서는 리싸이클링 현황이 조사 보고되었지만 비철금속 스크랩 전반에 대해서는 통계자료가 아직 공식적으로 발표되지 않고 있다. 본 고에서는 상용 비철금속인 동, 알루미늄, 아연, 연, 니켈 및 마그네슘에 대하여 최근 몇년(2010-2012년) 간의 국내 수요, 생산량과 스크랩에 대한 리싸이클링 현황을 조사하고 이를 토대로 리싸이클링율을 추정하였다.

• 자원리싸이클링
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• 제28권3호
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• pp.68-76
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• 2019

비철금속의 국내 수요 공급과 스크랩들의 리싸이클링 현황을 파악하는 것은 자원재활용 관련업계와 연구자들에게 매우 필요한 일이다. 국내에서는 10여 년 전부터 한국자원리싸이클링학회지를 통하여 3~5년 주기로 주요 비철금속의 수급과 스크랩 리싸이클링 현황을 조사, 발표하고 있는데, 전체 비철금속에 대해서 조사하기에는 분량이 너무 방대하여 사용량이 많은 범용 비철금속과 그 스크랩들에 국한하여 발표하고 있다. 본 조사연구에서는 기존 조사대상인 동, 알루미늄, 아연, 연, 니켈, 마그네슘 6종에 주석을 추가하여 총 7종의 비철금속에 대하여 관세청 수출입 통계와 한국비철금속협회 자료 및 비철산업 관련 정보지들을 통해서 최근 5년 (2014 ~ 2018년) 간의 국내 수급 현황을 조사하였고 이를 토대로 그 스크랩들의 재활용율을 추정하였다.

• 한국정밀공학회지
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• 제20권4호
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• pp.165-173
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• 2003

As the cycling time of new products have become more and more short in recent years, the demand for lowering the cost and reducing the production time becomes stronger. In order for the demand, the rapid prototyping and rapid tooling technology have been used. It has been widely known that RP technology has advantages with fabricating 3-D object having a complicated geometric shape. RP products, however, have a limitation with applying to the real die and mold because soft materials such as resin, paper and wax has been mostly used in RP technology. So in this paper, the RP products have been copied to semi-metallic soft tools using the mixture of metal fillers and epoxy resin. In order to evaluate the effect of the fillers on the characteristics of semi-metallic soft tools, three fillers are used including commercial aluminum powder, cast iron powder recycled by machining chips, and aluminum short fiber made by self-excited vibration technique. Besides, in the case of aluminum powder, the change of characteristics of semi-metallic soft tools is also tested according to the volume fraction of the powder.

• 한국기계가공학회지
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• 제21권1호
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• pp.49-55
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• 2022

Recently, the automobile industry has continued to demand lighter materials owing to international environmental regulations and increased convenience. To address this demand, aluminum parts have increased in popularity and are mainly developed and produced through hot forging and cold pressing. However, because this method has low yield and low production efficiency, a new manufacturing method is desirable. In this study, the water capacity efficiency of an aluminum inner tie rod socket was investigated using cold forging that provided a high yield and excellent production efficiency. Mechanical properties were derived through tensile testing of 6110A aluminum materials, and critical fracture factor and process analysis based on experimental data were carried out. The optimized process was applied as a prototype using cold multi-stage forging, and based on the derived results, the formability, productivity, and material efficiency of aluminum inner tie rod socket parts using this cold forging process was verified.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.814-819
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• 2000

The progress in the field of electronic materials has been especially significant for applications involving a range of electrical properties. Its importance is increasing with the increasing demand for integrated circuits. The sol-gel technique has been used for many years, and the metal alkoxides have featured prominently as source materials. The method consist of making a homogeneous solution of the component metal alkoxides in a suitable solvent, usually the parent alcohol; and then causing the hydrolysis under controlled conditions to produce a gel containing the hydrated metal oxide. The gel is then dried, and fired to produce a ceramic or glassy material at a temperature much lower than that required by the conventional melting process. This project consists of important theoretical considerations, processing techniques and applications related to electrophoresis derived thin films. In the electrophoretic process a metal alkoxide solution is gelled through hydrolysis-polymerization and converted the gel thin layer to an oxide by heating at relatively low temperatures.

• 한국군사과학기술학회지
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• 제15권4호
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• pp.519-526
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• 2012

Recently fuel cell is considered to be a new technology that can substitute the ICE(Internal Combustion Engine) as well as overcome environmental issues. In military applications, fuel cell has an unique advantages, which are quietness, namely, stealth. The environmental requirement such as shock and vibration in military application, however, is very severe comparing to civilian demand. Especially, the safety concerning hydrogen storage is the most important problem. Among the candidate methods to store hydrogen, the metal hydride storage is promising method owing to the storage mechanism of chemical absorption of hydrogen to metal hydrides. In this study, the new composition of Ti-Zr type metal hydride(A composition) was suggested and investigated to increase the hydrogen storage capacity. For comparison, the hydrogen charge-discharge properties were investigated with the commercialized Ti-Zr type metal hydride(B composition) using PCT(Pressure-Composition-Temperature) measurement. Also two hydrogen storage cylinders were loaded with each metal hydride and their hydrogen charging and discharging characteristics were investigated. As a result, it was found that the new Ti-Zr type metal hydride has a slightly higher hydrogen storage capacity compared to commercial Ti-Zr type metal hydride.

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2003년도 춘계 학술발표회 논문집
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• pp.209-212
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• 2003

한국의 금속광산은 일제시대에 금광산을 중심으로 본격적으로 개발되어 1943년 산금령시에 1,522개 광산이 가행되었다. 최근까지 1990개 광산이 개발된 것으로 알려지고 있으며 2002년 말 현재 7개 광산만이 가행되었다. 1960년대까지 국내 광산은 금, 은 동, 연아연, 철, 중석 등을 중심으로 활발히 가행되어 주요 외화 획득원으로 중요한 위치를 차지하였다. 그 이후 산업발전에 따라 수요는 증가세를 보인 반면 가행광산과 생산량은 매년 감소하여 최근 금속광물자원 자급도는 0.21%로 미미한 수준이며 수요의 대부분을 해외에 의존하고 있다. (중략)

• 소성∙가공
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• 제14권4호
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• pp.392-398
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• 2005

The deterioration of dimensional accuracy, caused by springback, is one of problems to always occur In sheet metal forming processes. As the demand for lighter and stronger metals increases, the development of improved forming processes settling the springback problem becomes more important. In this work, asymmetric springback phenomena are investigated, which occur in the shallow-drawing process with the anisotropic sheet metal and axisymmetric tools. The improvement possibility of dimensional accuracies, mainly, flatness, was examined by applying segmented blank holding forces as a method for springback control.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 춘계학술대회논문집
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• pp.389-392
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• 2003

The deterioration of dimensional accuracy, caused by springback, is one of problems to always occur in sheet metal forming processes. As the demand for lighter and stronger metals increases, the development of improved forming processes settling the springback problem becomes more important. In this work, springback phenomena are investigated which occur in the press forming process with the anisotropic sheet metal and axisymmetric tools. The improvement possibility of dimensional accuracies, mainly, flatness, will be examined by applying blank holding forces as a method of springback control.