• Proceedings of the KSME Conference
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• 2001.06a
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• pp.794-799
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• 2001

For the development of an electric molding machine with low energy, high performance, and high reliability, characterization, finite element analysis and fatigue strength analyses were performed. Strain was measured by strain gages bonded on electric molding machine and compared with stress analysis results using I-DEAS. The analyses showed good agreement with test results. By means of the comparison, we could draw an adequate boundary condition for the stress analysis of the components of electric molding machine. Additionally, we could verify the load distribution mechanism among the parts. The life prediction results for tie bar and thread zone showed infinite life.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.414-419
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• 2016

A study of a precision test according to the control method of an injection molding machine was carried out. The effects of the screw stroke, holding pressure, melt temperature on both the hydraulic and electric injection molding machine were examined. In addition, hypothesis testing was performed to determine the deviation of the data obtained in the experiments. The conclusions obtained in this study were as follows. Significant deviations in the screw stroke, melt temperature and holding pressure occurred in that order. The hydraulic type showed significantly more variation between the products compared to the electric type. In addition, using a mini tab from the statistics program, a hypothesis was proposed and the P value of the injection stroke, holding pressure, melting temperature injection stroke and melting temperature had adopted a null hypothesis ($H_0$). The holding pressure, which showed mutual differences, adopted an alternative hypothesis ($H_1$).

• The monthly packaging world
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• s.216
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• pp.128-134
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• 2011

1869년 미국의 Hyatt 형제는 상아 당구공의 대체 재료로서 셀룰로이드(질산섬유계 플라스틱)를 발명하고, 1872년에는 이 재료들을 성형하기 위해 세계 최초로 사출성형기를 개발했다. 하지만 유감스럽게도 성형된 셀룰로이드는 단단하면서도 약해 당구공으로는 사용할 수 없었으나, 브러시나 빗의 손잡이, 양복의 칼라, 사진의 필름, 탁구공 등으로 실용화되었다. 그 후 여러 기능을 가진 다양한 종류의 플라스틱이 잇따라 발명되었다. 이와 같은 플라스틱의 기능을 활용한 제품을 성형하기 위해 사출성형기는 끊임없는 기술개발을 통해 진화를 거듭해 왔다. 일본의 사출성형기 업계는 구미의 기술을 도입하며 발전해 왔다. 그 후 세계에서 제일 먼저 전동식 사출성형기를 개발해 실용화함으로써 최첨단 수준의 성능 및 기능을 달성해, 현재 많은 신기술제품의 중요한 수지부품생산에 공헌하고 있다. 아래에 항상 높은 수준을 추구하는 플라스틱업계의 니드에 부응하기 위해 계속되어 온 일본의 사출성형기의 기술개발 동향에 대해 그 개요를 소개한다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.189-192
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• 2002

Recently, micro-nano system is fabricated by photolithograph method. This method can not have mass production, so this method wastes time and human effort. accordingly, the aim of this paper is to research on injection molding of micro-nano system. For injection molding process, development of micro-nano mold is required. Mold for injection mold process is maintained its shape in high pressure and temperature. So in this paper, we studied the simulation of mold fur injection molding and then we consider a result of injection molding simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1999-2004
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• 2011

This research aims to develop polymer composites which can be used for PEMFC bipolar plate by injection molding process. Considering the moldability and stiffness, we used LCP(Liquid crystal polymer) as base resin. In order to improve electrical conductivity and mechanical properties, we chose carbon black, and both synthetic graphite and expanded graphite. The composites with different recipe are prepared for injection molding of PEMFC bipolar plate and CAE(Computer Aided Engineering) analysis was performed to predict melt flow and fiber orientation We did successfully fabricate the ASTM specimens by injection molding, and measure the electrical conductivity of the samples by using four point probe device. We measured mechanical properties such as flexural strength, flexural modulus and Izod impact strength. Conclusively, the electrical conductivity increased with increasing additive concentration, but both flexural strength and Izod impact strength decreased due to the brittle nature of carbon-based additives.