• 한국기계가공학회지
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• 제13권4호
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• pp.69-74
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• 2014

A waste gate valve (WGV) assembly for a gasoline turbocharger is typically manufactured by means of precision casting. In this study, however, it was newly manufactured in a more innovative way, metal injection molding (MIM) using Inconel 713C alloy, and its performance was tested in a 1.6L direct injection gasoline engine by a thermal shock durability test that lasted 300 hours, after which the results were compared to those of a precision-cast WGV assembly with regard to the engine intake boost pressure, turbine wheel speed, and transient intake pressure. It was found that the two WGV assemblies showed similar performance levels throughout the durability test.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2009년도 춘계학술대회 논문집
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• pp.13-14
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• 2009

• 한국정밀공학회지
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• 제32권11호
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• pp.969-976
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• 2015

In the present study, a numerical investigation of an insert injection molding process was carried out for the development of thermoplastic microfluidic chip plates with metal electrodes. Insert injection molding technology enables efficient realization of a plastic-metal hybrid structure and various efforts have been undertaken to produce novel components in several application fields. The microfluidic chip with metal inserts was proposed as a representative example and its molding process was analyzed. The important characteristics of the filling stage, such as the effects of filling time and thickness of the part cavity, were characterized. Furthermore, the detailed distributions of pressure and temperature at the end of the filling stage were investigated, revealing the significance of metal insert temperature.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 추계학술대회 논문집
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• pp.271-274
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• 2007

Housing and insulation of electrical connectors are made of plastic resin by injection molding process. The metallic inner tube is easily deformed by high pressure during the injection process. In order to prevent deformation of the inner tube, it is desirable to simulate it by structural CAE analysis. However, it takes a long time to calculate the stress- of the part by commercially available injection molding CAE software with sufficient accuracy. In this study, structural analysis in conjunction with injection molding analysis is proposed to improve accuracy of the structural analysis. Pressure distribution on the inner tube is predicted by the injection molding CAE analysis, and then mapped onto the mesh of structural analysis by a mapping algorithm developed in this study. As a result reliable result is obtained in shorter time than the conventional method. The predicted deformation of the inner tube is compared with the actual part after experiment.

• 한국산학기술학회논문지
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• 제15권1호
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• pp.21-26
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• 2014

치과에서 사용되는 구강 치료용 요오드 용기는 개폐 시 용기의 캡에 부착되어 있는 칼날에 의해 치료용 실은 절단이 된다. 금속의 칼날은 요오드 용액과 반응하여 단기간에 부식이 되는 문제로 인해 환자의 위생에도 영향을 준다. 이러한 문제를 해결하기 위해 최근 세라믹 칼날로 대체되어진 제품들도 개발되어 생산되는데, 이때 세라믹 칼날은 수작업과 기계가공을 통해 만들어 진다. 본 연구에서는 세라믹 칼날을 분말사출성형공정으로 대량 생산할 수 있도록 20Cavity의 균일 충전을 위한 유동 시스템을 제안하였다. Moldflow를 이용하여 20cavity 유동성에 대한 시뮬레이션을 진행하였고, 금형제작과 수정을 통해 금형을 완성하였다. 사출성형 후 탈지와 소결공정을 통해 완성하고, 금형에 세라믹 칼날을 인서트 사출하여 캡 제품을 완성하였다. 본 연구를 통해 유효한 절단 성능을 갖는 세라믹칼날 대량생산 가능성을 검증하였다.

• 한국산학기술학회논문지
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• 제10권4호
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• pp.702-706
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• 2009

본 연구에서는 시작형 몰드재료로 우레탄 레진(TSR-755)을 이용하여 레이저 조형으로 다양한 형태의 냉각 채널을 가진 몰드로 가공했을 경우, 사출성형 상용패키지(Simpoe-Mold)를 사용하여 냉각채널 변화에 따라 사출물의 냉각시간과 변형량을 비교 검토 하였다. 해석결과, 사출물 주변의 적절한 냉각채널배치로 기존 금속재질의 시작형 몰드 대비 19% 최대 변형량 감소와 46%의 냉각시간 단축이 가능한 것으로 나타났다.

• 동력기계공학회지
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• 제2권1호
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• pp.80-85
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• 1998

Engineering plastics have been magnified its usability due to its outstanding mechanic al, electrical and chemical properties, for example, in the area of computer, electricity, electronics, automobile, camera industry. In recent, automobile speedometer system is changing from manual operation to motor operation. All plastic gears inserted by metal shaft are used In motor operated speedometer system. Therefore, in this research, experimental investigation of the shrinkage phenomenon was executed according to various inserted depth and injection conditions. In experiments, the inserted depth was controlled as 30% and 90% of the total thickness of the plastic gear. The main parameters of injection process were selected as injection pressure, holding pressure, melt temperature, injection rate. As main results, free shrinkage rate of the test part is increased about 4 times to restricted shrinkage rate and shrinkage phenomenon against all injection conditions have a trivial effect on the test parts as conventional parts.

• Design & Manufacturing
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• 제17권4호
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• pp.57-62
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• 2023

As a representative method for mass production, a multi-cavity type mold capable of simultaneously molding products of the same shape can be applied. It has the advantage of improving the productivity from several times to several tens of times, but it may cause disadvantages which is the quality deviation with each cavity. This study, therefore, has tried to increase the cavity filling balance by using a melt flipper and a flow distance control part in the runner part of the mold. Along with this, the design and manufacturing of air vents during injection molding have been verified through experimental methods to achieve a higher level of multi-cavity filling balance and dimensional accuracy.

• 한국자동차공학회논문집
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• 제7권9호
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• pp.112-118
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• 1999

Shrinkage behavior was investigated to obtain more accurate dimensions of injected molding parts for free and restricted shrinkage conditions. various parameters for metal inserted injection process, such as thickness of resin, holding pressure and time, mo이 temperature and restriction condition of mold, were considered for the analysis of shrinkage phenomena. For numerical analysis, MOLDFLOW software was used to find the deterministic parameters of filling time, temperature, pressure and holding time. Also , experimental shrinkage effects were measured through actual injection molding process and the resin thickness was under controlled as 3 mm , 5 mm, and 7mm for the shapes of plastic gear made of Polymide(PA) and Polyxymethlene(POM). The main parameters of these injection processes were found to be holding pressure, holding time and mold temperature in the case of metal inserted molding.

• 한국분말재료학회지
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• 제7권4호
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• pp.228-236
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• 2000

An investigation was carried out on the possibility whether the ball-milling process of low energy could successfully improve the packing density and flowability for MIM application in W-20wt%Cu system. In this study, W-20wt%Cu powder mixture was prepared by ball-milling. W powder was not fractured by low mechanical impact energy used in the present work during the critical ball-milling time, but the ductile Cu powder was easily deformed to the 3 dimensional equiaxed shape, having the particle size similar to that of W powder. The ball-milled mixture of W-20wt%Cu powder had the more homogeneous distribution of each component and the higher amount of powder loading for molding than the simple mixture of W-Cu powder with an irregular shape and a different size. Accordingly, the MIM W(1.75)-20wt%Cu powder compacts were able to be sintered to the relative density of 99% by sintering at $1400^{\circ}C$ for one hour.