• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.1
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• pp.21-26
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• 2014

When iodine container for dental mouth treatment is opened, thread for treatment is cut by the blade in cap of container. Due to the problem of corrosion in a short period time after the reaction of metal blade to iodine solution, it gives impact on patient hygiene. In order to solve the problem, alternative products such as ceramic blade are developed and produced recently. In case of ceramic blade, it is produced by handwork and machine work. In this study, for the quantity production of ceramic blade with powder injection molding, we proposed a delivery system to have uniform charge of 20 cavity. Using Moldflow, simulation on 20 Cavity flow was performed. And then the mold was obtained through mold production and modification.(based on simulation) After injection molding, debinder, sintering process was achieved for ceramic blade, and the cap product was completed via insert injection on ceramic blade. In this study, we verified possibility of quantity production of ceramic blade which showed effective performance for cutting.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.106-111
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• 2002

The object of this study is a manufacture of burr die using CAD/CAM systems. Systems are consist of AutoCAD, CAM software and CNC milling machine. CAM software is purpose of G-code generation for CNC programming. Then CAM software and CNC milling machine are connect to RS-232-C cable for networking.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.114-118
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• 1996

Evaluation of cutting condition is one of the most important aspect to improve productivity and quality. In this study, the wear and cutting characteristics(cutting force, acoustic emission signal and surface roughness) of ceramic cutting tool for hardened die material(SKD11) were investigated by experiment. Flank wear on relief face of tool was occurred more dominant than crater wear on rake face. Experiments were performed under the various cutting condition.

• Transactions of Materials Processing
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• v.7 no.1
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• pp.72-80
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• 1998

This study is concerned with the thermo-biscoplastic finite element analysis of hot tube extrusion through square dies with a mandrel. The problem is treated as a non-steady state and the ALE description is used due to abruptly turning flow at the die aperture. Since the contact heat transfer coefficient and the friction factor are required in the analysis experiments are also carried out to determine the values, In order to apply ceramics to an extrusion die the study is focussed on under-standing the characteristics of the process. The simulated results provide the useful informations such as metal flow temperature distribution stress state etc. The elastic analysis of the dies is carried out to obtain the stress state of the ceramic dies.

• Proceedings of the KAIS Fall Conference
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• 2001.05a
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• pp.298-299
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• 2001

안경렌즈는 유리를 연마하여 제작하거나 단량체를 세라믹 금형에 넣어 캐스팅공법으로 플라스틱 렌즈를 만드는 것이 일반적인 방법이었다. 한편 사출성형에 의한 렌즈 및 안경의 제작은 광학적으로 우수한 재료 및 금형을 개발하지 못하여 국내에서는 시도조차 못하는 형편이다. 구미나 유럽의 일부 국가는 PMMA 및 PC를 이용하여 안경 및 안경렌즈를 개발하고 있으며, 이는 공정을 대폭 줄이기 때문에 대량 생산 및 원가 절감을 이룩할 수 있다. 본 연구에서는 PMMA 및 PC를 이용하여 그동안 성형할 때에 가장 문제가 되었던 오목 렌즈를 제작하기 위한 근본적인 금형 설계의 문제점 해결과 이를 이용한 일체형 안경과 고강도 렌즈의 제작을 고찰하였다.

• Journal of the Korean Society for Heat Treatment
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• v.18 no.6
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• pp.383-393
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• 2005

본 고에서는 사출금형소재로 널리 사용되는 프리하든 강의 수명을 극대화 시킬 수 있는 열 표면처리 기술에 대해 소개하였다. 이러한 열 표면처리 기술 및 기술 적용시 고려해야할 점을 다시 정리해 보면, 제조하는 대상물을 고려한 최적 금형 재료의 선택 (표 1~3) 선택된 금형의 물성을 최적으로 구현할 수 있는 열처리 선택 (표 4) 금형의 사용 환경을 고려한 최적 열 표면처리 선택 (표 5) 질화 열처리에 의한 수명 향상 피로 수명이 중요한 경우 : 질화층 $100{\mu}m$이내 열간 내마모성, 크립저항성이 요구되는 경우 : 질화층 $300{\sim}400{\mu}m$ TiN, CrN 등 세라믹 코팅에 의한 성능 향상 내식성 중요시 CrN, DLC의 적용 내마모성 및 초저마찰계수의 구현 : 방향성 코팅, 나노구조화 금형의 국제경쟁력을 향상시키기 위해서는 고품위 금형 제조 기술이 필요하고 이를 위하여, 표면개질처리가 필수불가결하다는 것이다. 또한, 열 표면처리에는 각각의 특징이 있고, 적용 상황의 미묘한 차이에 따라 특성이 바뀌기 때문에 고품위, 품질 금형을 얻고자 하면 어느 때보다 사용자, 금형기술자, 열 열 표면처리 기술자들과의 협력이 요구된다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.11a
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• pp.882-886
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• 1996

The use of ceramics for extrusion dies is limited since the modification of die design is difficult. In order to successfully apply the ceramic dies to extrusion dies, a better understanding of the process should be preceded. This study focuses on understanding the characteristics of the process. In the present study, a hot extrusion of tube with a mandrel is analyzed by ALE finite element method. In order to obtain the stress state of ceraminc dies, the elastic analysis of dies is also carried out.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.6
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• pp.36-41
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• 2012

In this study, we turning plastic mold steel (STAVAX) against cutting speed, depth of cut, feed rate using whisker reinforced ceramic tool (WA1). To predict cutting force, analyze principal, radial, feed force with multi-regression analysis. Results are follows: From the analysis of variance, affected factor to cutting force feed rate, depth of cut, cutting speed in order and cutting speed was very small affect to cutting force. From multi-regression analysis, we extracted regression equation and the coefficient of determination$(R^2)$ was 0.9, 0.88, 0.856 at principal, radial and feed force. It means regression equation is significant. From the experimental verification, it was confirmed that principal, radial and feed force was predictable by regression equation.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.9
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• pp.118-124
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• 2002

The use of ceramic inserts in hot extrusion dies offers significant technical and economic advantages over other forms of manufacture. In this paper, process simulation and stress analysis are thus combined during the design, and a data exchange program has been developed that enables optimal design of the dies taking into account the elastic deflections generated in shrink fitting the die inserts and that caused by the stresses generated in the process. The shrink fit analysis has been performed that enables optimal design of the dies taking into account the elastic deflections which generated in shrink fitting the die inserts and that caused by the stresses generated in the process and by using DEFORM software for process analysis. This data can be processed as load input data for a finite element die-stress analysis. Process simulation and stress analysis are thus combined during the die design. The stress analysis of the dies is used to determine the stress conditions on the ceramic insert by considering contact and interference effects under both mechanical and thermal loads. The results are compared with the experimental ones for verification.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2002.02a
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• pp.231-238
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• 2002

미세 절삭에 의한 마이크로 형상가공 및 이를 이용한 미세금형 가공기술개발을 위하여 절삭 공구를 이용한 기계적 미세 가공법에 대한 고찰과 더불어 shaping, end-milling, drilling 등의 가공이 가능한 기계적 미세 가공시스템을 구성하고 이를 이용한 미세 치형 그루브와 미세 격벽 등 미세 형상 구조의 금형 개발을 위한 가공실험을 수행하였다. 본 실험에서는 먼저 shaping 방식으로 세 종류의 다이아몬드 바이트를 사용하여 알루미늄, PMMA, Nickel, 황동 등의 소재에 pitch $150{\mu}m$, 높이 $8{\mu}m$ 내외의 미세 치형의 금형 코어를 가공하였고, 다음으로 Z축에 air spindle을 설치하여 $\phi0.2mm$의 end-mill(WC)을 사용하여 황동 소재에 깊이 $200{\mu}m$, 폭 $200{\mu}m,\;100{\mu}m,\;50{\mu}m,\;30{\mu}m$의 두께 변화를 주어 미세 격벽에 대한 가공실험을 하였다. 미세 구멍가공실험으로는 drilling 전용장비를 구성하여 $\phi0.6\~0.15mm$의 drill공구로 SM45C와 세라믹$(Si_3N_4-BN)$ 소재에 스텝이송방식에 의한 미세 구멍 가공 실험을 실시하였다.