• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.225-226
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• 2006

In this present investigation, Metal Injection Moulding (MIM) of M2 High Speed Steel (HSS) parts using a wax-High Density Polyethylene (HDPE) binder is shown. The elimination of organic binder was carried out by thermal debinding under inert atmosphere. In order to keep carbon in the sample that could improve the sintering process, incomplete debinding was performed between 450 and $600^{\circ}C$. The specimens were sintered at temperatures between 1210 and $1280^{\circ}C$ in high vacuum atmosphere, obtaining the 98% of the theoretical density. In the samples with higher residual carbon content, the sintering window was extended up to 20 degrees and the optimum temperature was lower.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.507-508
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• 2006

In this communication the development of a new metal injection moulding (MIM) system for duplex stainless steels is presented. The metal powders were prepared by premixing 316L and 430L stainless steels gas atomised powders in a ratio of 50:50. The binder used to prepare the feedstock was composed by HDPE and paraffin wax. Torque measurements of the mixture indicated that the maximum amount of metal was 68 vol%. The polymeric part was driven off by thermal debinding and the sintering was performed in low vacuum. The final densities were close to the theoretical ones.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 추계학술대회논문집
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• pp.201-206
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• 2003

Plastic injection mould have two kinds of trouble, one is in mould another in injection parts. Most of defects of the former take the cause in a design like in structure and working, the later weld line, transforming, sink mark, burning, flow mark, scratching, shading, black hole and so on. Most of problems of the later is difficult for making a clear definitely the reason of defects because of complexible. The purpose of this paper is to improve the quality of plastic injection mould and parts with inquiring the counter plan and rouble of the part of Flat TV Front Cover by flow control method and gas- assisted injection moulding. For minimizing defects from injection moulding parts, this paper was investigated with using computer aided injection mold filling simulations. Based on these numerical results, I established guidelines mould design and injection processing condition. As a results I got the improve of quality, minimizing surface defects moulded parts and troubles in mould.

• 대한기계학회논문집A
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• 제34권10호
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• pp.1487-1492
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• 2010

본 논문의 목적은 3 차원 사출성형해석을 통한 냉장고 플라스틱 서랍 제작용 사출성형 금형의 형상적응형 냉각수로 설계이다. 바람직한 형상적응형 냉각수로의 설계를 얻기 위하여 형상적응형 냉각수로의 직경과 위치가 사출성형 특성과 제품의 품질에 미치는 영향을 정량적으로 고찰하였다. 해석결과로부터 제품의 균일 냉각과 변형 최소화가 가능한 최적의 형상적응형 냉각수로의 설계를 도출할 수 있었다. 본 연구에서 제안된 사출성형 금형과 기존의 직선형 냉각수로의 사출성형 금형을 냉각/제품 제작 시간 및 제품 품질 측면에서 비교한 결과, 형상적응형 냉각수로를 가진 사출성형 금형이 제품의 생산성과 품질을 동시에 향상시킬 수 있음을 알 수 있었다.

• 한국고분자학회지:고분자과학과기술
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• 제6권6호
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• pp.610-617
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• 1995

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.399-400
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• 2006

M390 microclean(R) of $B{\ddot{o}}hler$ Edelstahl is a powder metallurgical plastic mould steel with a high level of corrosion and wear resistance and therefore often used in the plastics processing industry. But as a consequence of rapidly advancing developments in the plastics processing industry the required level of wear resistance of tool steels in this field is constantly rising. For that reason a new PM tool steel with higher hardness values and an increased amount of primary carbides has been developed to improve the resistance against abrasive and adhesive wear. The wear resistance of both steels against adhesive situations for components of the plastification unit of injection moulding machines has been tested with a novel method. In case of processing polyolefins with an injection moulding machine it was found that there is adhesive wear between the check-ring and the flights of the screw tip of the non-return valve under certain circumstances. The temperature in that region was measured with an infrared temperature sensor. The existence of significant peaks of that signal was used as an indicator for an adhesive wear situation.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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• pp.269-274
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• 2001

This research covers the development of new technique for composite injection molding of high stiffness Sabot. An analysis of polymer resin is performed by means of making test specimen mold and doing test with accordance of ASTM test guidelines. Structural analysis and simulation of injection molding process are carried out in order not only to estimate but also to predict the characteristics of molding stresses what both product and structure of mold may have. For structural analysis software, Moldflow and LS-dyna are used and universal test machine is utilized for evaluating performance of sabot. Cases of adopting this material to sabot are not announced yet in domestic academic world. In addition to that, materials for polymer-metal mixed injection molding are imported on the whole due to deficient level of domestic technology. Therefore, this new developed injection molding technique using PEI material can make it available to ensure the technology of making mold, injection and design. Finally, this technique may be applicable to another sabot having different radius of warheads from now on.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2003년도 춘계학술발표논문집
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• pp.136-139
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• 2003

• Korea-Australia Rheology Journal
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• 제14권4호
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• pp.143-159
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• 2002

Although much progress has been made in the computation of Eulerian steady flows with high viscoelasticity, less work has been done for the case of transient flows. Because of their importance in injection moulding, blow moulding and other forming processes, as well as their Intrinsic interest, we believe more attention should be focussed in this area. Hence in this paper we review progress in unsteady flow computations with high elasticity, and show some new results in this area.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 추계학술대회 논문집
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• pp.445-446
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• 2012