• Journal of Korean Ophthalmic Optics Society
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• v.6 no.1
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• pp.145-148
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• 2001

SiC composites were developed by incorporating glass phase into SiC, in the light of improving mechanical properties of material for spectacle lens cutting. Specimens for spectacle lens cutting with glass phase as sintering additives have been fabricated by hot-pressing at $1810^{\circ}C$ for 2 hr under a pressure of 25 MPa. The fracture toughness and hardness of hot-pressed specimens were characterized and compared with previous works. Typical hardness and fracture toughness of materials for spectacle lens cutting were 12 GPa and $5.1MPa{\cdot}m^{1/2}$ respectively.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1994.10a
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• pp.44-48
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• 1994

The cutting process of cage motor rotor require high precision and good roughness. The surface roughness of cutting face is very important factor with effect on the magnetic flux density of cage motor rotor. The paper describes a cause of decrease in the cutting force and roughness on low temperature cooling tool by means of analysis on the mechanism of force system at cutting confition and experimental findings. The main results as compared with the room temperature cutting are as follow : 1) The cutting resistance decreased due to low temperature cooling tool. 2) The surface roughness decreased due to low temperature cooling tool.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.6
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• pp.274-278
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• 2014

Machining performance is often limited by chatter vibration at the tool-workpiece interface. Chatter vibration is a type of machining self-excited vibration which originated from the variation in cutting forces and the flexibility of the machine tool structure. Cutting tooling method is one of major factor to chatter vibration in turning process. Even though lots of cutting tooling methods are developed and used in machining process, precise analysis of cutting tooling effect in view of chatter vibration behavior. This study presents numerical and experimental approaches to verify and effects of various cutting tooling geometry and clamping method on the onset of chatter vibration. Acquired knowledge from this study will apply the optimal geometry design of cutting tooling and adjusting of machining process.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.62-62
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• 2003

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.87-87
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• 2003

• Journal of Korean Society of Steel Construction
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• v.27 no.1
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• pp.77-85
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• 2015

This paper describes the development of force limiting device(FLD). The FLD could induce compressive yield before occurring elastic buckling for slender member under compressive load. Therefore, it might prevent reduction of load carrying capacity by elastic buckling and the structures with the devices would behave stable. A new type of FLD reduced cross area is proposed in this study different to existing studies like as out of plane type, slit type and folded plate type. The parameters of specimens are depth, width and number of cutting. The structural capacity and characteristics of proposed types were verified by experiment and FEM analysis. The FLD of cutting type is efficient in compressive member.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4149-4155
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• 2013

High speed machining for higher cutting speed and feedrate lead to a increase of surface quality and material removal rate. This paper presents a study of the influence of cutting conditions on the vibration characteristics obtained by machining with face milling cutter for high speed machining. In this paper, Taguchi experimental design method which is based on orthogonal array table was applied to study vibration characteristics with high speed face milling cutter. The experimental conditions used orthogonal array of $L_{27}(3^{13})$. In this work, design and analysis of experiments is conducted to study the effects of these parameters on the vibration by using the S/N ratio, analysis of variance. Four cutting parameters namely, feed rate, champer length, cutting speed, and depth of cut were optimized with consideration of vibration characteristics.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.327-327
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• 2004

광통신망 구축에 있어 광섬유의 접속을 위한 광접속기 소자의 하나로 광섬유 정렬의 핵심부품인 페룰이 있다. 광페룰은 통신품질의 향상에 따라 고정밀도의 품질수준을 요구되고 있으며, 이러한 광부품인 페룰을 가공하기 위해서는 동축연삭기의 초정밀 초미세 가공설비가 요구되고 있다. 이러한 광페룰 가공용 초정밀 연삭기의 경쟁력을 확보하기 위해서는 무하시 절삭력 또는 절삭토오크의 영향을 받지 않고 운전시의 정적 특성 및 동적 특성 영향을 최대한 배제할 수 있는 동축 연삭기가 요구된다.(중략)

• Journal of the Korean Society for Precision Engineering
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• v.15 no.4
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• pp.36-43
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• 1998

We experimented turning SCM440, called difficult-to-cut materials in general, using tungsten carbon tool(PIO) in order to elevate machinability by a new cutting method. The cutting tool designed and made to study was cooled to -17$0^{\circ}C$ in about 1 minute by liquid nitrogen. Then, we operated cryogenic cutting by cooling tool with liquid nitrogen and stuided the effect about cutting force, chip thickness, surface roughness, behavior of tool wear and cutting temperature. In addition, we investigated the possibility that sur face roughness of workpiece can be predicted analyzing cutting characteristics.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1990.04a
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• pp.67-75
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• 1990

세라믹스는 우수한 기계적, 전기적, 화학적성질로 인하여 여러방면에서 점점 기대가 높아가 고 있다. 그럼에도 불구하고, 그 이용 범위나, 응용이 늦은 것은 가공성에 문제가 있기 때문 이라 해도 과언이 아닐 것이다. 세라믹스의 가공법으로서는 주로 다이야몬드 지립을 이용한 연삭, 절단, 래핑등이 행하여지고 있지만 이러한 방법은 가공 능률이낮기 때문에 생산성에 많은 문제를 안고 있다. 본 연구에서는 다이야몬드공구와 산화물계 A1$_{2}$0$_{3}$를 피삭재로 하여 다양한 절삭조건과 공구의 형상을 변화시켜 선삭 실험을 통하여 절삭력의 크기, 칩의 형태, 공작물의 형상, 표면조도 및 공구마멸등 절삭의 특성을 검토 하였으며 절삭에 의한 파인세라믹 스의 가공 가능성을 확인하고자 한다.