• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 추계학술논문집 2부
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• pp.514-517
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• 2011

본 연구에서는 사각형태 화장품 케이스 사출성형 시 발생되었던 수지 미성형 불량을 해결하기 위하여 사출성형해석 기술을 통해 성형품 형상변경 및 사출금형 내 유동 시스템 수정방안 도출을 수행하였다. 대상제품인 사각형태 화장품 케이스는 상측부 케이스로서 케이스 외관에 게이트 및 취출흔적이 남지 않아야 함에 따라 측면부 게이트 적용으로 유동거리가 길어져 미성형 불량이 다수 발생하는 제품이다. 따라서, 수지 유동성 향상과 더불어 효율적인 보압전달을 통하여 수지 충전 및 변형발생 저감을 위하여 성형품 형상변화 및 유동시스템 변화에 따른 사출성형해석을 수행하고 결과를 고찰하였다. 이로써 최종적으로 수지 미충전으로 인한 미성형 불량을 제거하고 성형품 변형을 줄일 수 있는 수지유동시스템 수정방안을 제시하였다.

• 한국기계가공학회지
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• 제14권5호
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• pp.75-80
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• 2015

Nowadays, flat-shaped cover glass is widely used for mobile devices. However, for its good design and convenience of use, curved cover glass has been demanded. Thus, many companies have tried to produce curved cover glass through the shaving technique, but the production efficiency is very low. Therefore, the molding technique has been adopted to increase the efficiency for the curved-glass production system. For a glass-molding system, several heating blocks are installed, and the flat cover glass is sequentially heated and molded. The production time for the cover glass is very different depending on the heating conditions; thus, the prediction of the production time for different heating conditions should be needed. Therefore, in this study, the computations were performed with different heating conditions (uniform and non-uniform) in the present cover glass-molding machine. For uniform and non-uniform heating conditions, the simple correlation between the heating time and the heater capacity and the heating time to achieve higher durability can be suggested, respectively.

• 대한기계학회논문집A
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• 제25권10호
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• pp.1575-1582
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• 2001

Injection molding is widely used in producing various plastic parts due to its high productivity, and the demand for injection molded products with high precision is increasing. To achieve successful product quality and precision, the design of gating and runner system in injection mold is very important because it influences the melt flow into the cavity. Some deflects, such as weld lines and overpacking, can be effectively controlled with proper selection of gate locations. In the present study, the design of gate locations in injection molding of a dashboard fur automobiles was carried out with CAMP mold, a PC-based simulation system for injection molding. A dummy runner system was developed to simulate a runner system in order to increase the efficiency of the analysis procedure. The numbers and locations of gates were iteratively determined in the present investigation. In this procedure, an acceptable design was obtained in terms of reducing the maximum pressure and clamping force.

• Composites Research
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• 제12권1호
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• pp.11-18
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• 1999

섬유로 강화된 열가소성 복합재의 성형과정 중에는 유동특성에 미치는 금형내 충전패턴의 제어나 섬유배향 및 섬유함유율과 같은 성형공정 인자들의 영향을 예측하는 것이 필요하다. 본 연구에서는 등온상태에서 두께가 얇거나 두꺼운 성형품을 압축성형하는 경우에 발생하는 유동선단과 압력분포, 속도구배 등을 예측함을 목적으로 한다. 이때 복합재는 비압축성 뉴턴유체로 하였으며, 성형공정 변수들에 미치는 미끄럼 지배상수 $\alpha$와 점성비 $\zeta$의 영향에 대해서 고찰한 내용을 보고한다.

• 한국분말재료학회지
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• 제8권4호
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• pp.245-252
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• 2001

Recent remarkable progress in the semiconductor industry has promoted smaller size of semiconductor chips and increased amounts of heat generation. So, the demand for a substrate material to meet both the characteristics of thermal expansion coefficient and heat radiation has been on the increase. Under such conditions, tungsten(W)-copper(Cu) has been proposed as materials to meet both of the above characteristics. In the present study, the W-10wt.%Cu powders were synthesised by the mixing and hydrogen reduction of the starting mixture materials such as W-Cu, $W-CuCl_2$and $WO_3-CuCl_2$ in order to obtain the full densification. The W-10wt.%Cu produced by hydrogen reduction showed the higher interparticle friction than the simple mixed W-10wt%Cu because of the W agglomerates. In the dilatometric analysis the W-10wt.%Cu prepared from the $W-CuCl_2$was largely shrank by heating up $1400^{\circ}C$ at the constant heating rate of $5^{\circ}C$/min. The possibility of application of metal injection molding (MIM) was also investigated for mass production of the complex shaped W-Cu parts in semiconductor devices. The relationship between the temperature of molding die and the pressure of injection molding was analyzed and the heating up stage of 120-$290^{\circ}C$ in the debinding process was controlled for the most suitable MIM condition.

• Design & Manufacturing
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• 제9권2호
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• pp.20-24
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• 2015

Recently, the light guide plate (LGP), a component of the BLU, becomes thinner and larger than ever. In industrial field, specialized injection molding technique is applied to mold the ultra-thin LGP such as a ultra-high speed injection molding. Usually very high melt temperature is used for low viscosity. High injection speed and melt temperature lead to yellowing of LGP. In the present paper a series of injection molding experiment was performed under various injection molding conditions. Yellow index, CIE xy, spectral transmittance of sample were measured using the UV-Visible spectrophotometer. Systematic decrease of spectral transmittance in UV-B range was found as the melt temperature was higher. Yellow index and CIE xy were became higher near the gate location in LGP. From the result of analysis of variance, the main factor to affect for yellow index was mold temperature and that for spectral transmittance(at 315 nm) was melt temperature.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.671-672
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• 2013

• 연구논문집
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• 통권25호
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• pp.5-12
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• 1995

Mold platen are one of the most important structural components of the injection molding machine. Mold platen had been designed, and manufactured based on the experience and the method of trial and error. Recently, as the computer progress, the numerical simulation method using commercial finite element analysis code has been used to analyze the characteristics of components. It's a urgent problem to reduce the weight of mold platen while preserving the safety and reliability for the structual failure. Finite element analyses to establish basic design technologies and reducing the weight of mold platen were carried out. As result, we are obtained the about 10% reducing the weight for mold platen.

• 오토저널
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• 제13권3호
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• pp.13-18
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• 1991

여기서는 자동차 분야중 Plastic이 가장 많이 적용되고 있는 Bumper의 초기 설계 가능성 확인(Feasibility study) 및 최적 설계를 위한 유동해석, 구조해석 그리고 Blow Molding Back-Beam 해석을 위한 PITA(Polymer Inflation and Thinning Analysis) 등의 기법들에 대한 내용 및 적용 방법 등에 대하여 서술하였다. 특히, Energy Absorbing 역할을 하는 Back-Beam은 Blow Molding에 의한 설계방법에 촛점을 맞추었다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.451-452
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• 2011