• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.1
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• pp.5-23
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• 2010

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.10a
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• pp.21-21
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• 2003

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.921-926
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• 2015

Embossed aluminum sheets were been used in heat insulation purpose for automative exhaust parts because of increasing their surface areas and stiffness reinforcement. However, there are many restrictions because of high rate of wrinkle occurrence on press working. We have performed the tensile and bending tests for embossed sheets to clarity its mechanical properties and springback characteristics. Embossed aluminum sheets showed a different flow stress after plastic yielding due to flattening the embossed cone shape. Above all, yield stress of parallel embossed specimen decreases while its diagonal one increases and the decrease of young's modulus in the embossed sheets contributes to the increase of springback amount.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1996.05a
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• pp.219-226
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• 1996

일반적으로 밀폐 형단조공정에서 약 10,000톤의 성형력이 필요한 직경이 540mm인 플랜지 형태의 알루미늄 7175 합금 단조품을 2,500톤 프레스에서 단조하기 위한 공정연구를 하였다. 장비의 성형력 부족을 극복하기 위하여 업셋단조와 기계가공 및 전방압출을 조합한 복합성형공정을 제안하였으며, 복합공정은 실제재료를 이용한 $\frac{1}{4}$ 축소 모델 실험과 유한 요소 해석으로 그 타당성이 판단되었고, 선정된 프레스에서 실물 크기의 플랜지 단조 가능성을 확인하였다.

• Proceedings of the KAIS Fall Conference
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• 2006.11a
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• pp.265-268
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• 2006

프레스 금형은 대표적인 소성변형에 의한 가공법이다. 금형을 제작하여 프레스에 장착하고 제품을 생산하게 되면 피할 수 없는 문제가 금형의 파손에 관한 것이다. 금형의 파손에는 여러 가지 문제가 있을 수 있지만 그중 중요요인 중 하나가 열처리에 의한 것이다. 본 연구에서는 실제 현장에서 발생된 파손 금형의 일부형태를 파악하고 원인을 분석하고자 한다.

• Transactions of Materials Processing
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• v.8 no.1
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• pp.38-46
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• 1999

This paper deals with the shape fixability of press formed parts through the use of a V-bending process and a U-bending one. The influence of material properties on the shape fixability in forming processes was investigated. A V-bending process had on optimum ben radius for each combination of parameters which caused maximum shape fixability. In the U-bending process the blank holder force could control the degree of shape fixability. A ha호 blank holding force resulted in a uniform strain distribution and increased shape fixability.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1995.06a
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• pp.55-63
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• 1995

Press accidents are one of the most popular industrial accidents. Two factors are considered to lead to press accidents, one is human, the other press machine itself. Accident itself is analyzed and concluded to be due to incomplete interaction between press and human. A press design considering safety as a methodology is introduced to reduce the industrial accidents by press machine, that is micro-inching locking system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1997.03a
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• pp.261-264
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• 1997

A single action press robot, which consists of a driving unit, rotator, up-down feed base and feed bar, is developed and applied for the press automation. The driving unit is made up with a face cam and blade cam, which have a phase angle. The feeding system consists of a double speed-up apparatus and linear motion guides, and has a fast motion characteristics. A horizontal feeding speed of the feed bar is increased twice by the double speed-up apparatus. The driving mechanism could be simplified due to the speed-up of the feeding unit.

• Transactions of Materials Processing
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• v.9 no.2
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• pp.171-178
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• 2000

This paper is concerned with the optimization of the drive for linear-guide press which is one of mechanical presses. The design of linear-guide drive for a mechanical press is introduced and the drive for the linear-guide press is optimized for the improvement of load and velocity characteristics. As a result of optimization, the load capacity during stroke increases and the slide velocity decreases in working region, respectively. The new design could be suited to many applications in precision forming such as extrusion and the sheet metal-forming processes.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.357-364
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• 2004

합금화용융아연도금강판(GA)은 가격이 저렴하고 내식성 및 용접성이 우수하여 최근 자동차용강판으로 그 사용량이 급격하게 증가하고 있으나 도금밀착성이 나쁘고 프레스성형이 떨어지는 단점을 가지고 있다. 본 연구에서는 GA 도금층에 여러가지 유,무기계 윤활처리를 실시하여 이것이 마찰특성은 물론 용접성, 도장성 및 내식성에 미치는 영향을 평가하였다. 유기계 윤활피막은 가공성과 도금 밀착성에서 유리하나 용접성과 탈지성에서는 불리하였고, 무기계 윤활피막인 Prephosphate 및 금속윤활처리 강판은 가공성에서는 유기윤활피막 보다 약간 떨어지나 용접성과 탈지성에서는 우수한 결과를 나타냈다.