• 대한기계학회논문집A
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• 제38권9호
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• pp.953-958
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• 2014

형상적응형 냉각회로를 구비한 사출금형 및 히트 싱크를 가지는 절삭공구 (혹은 냉각 장치) 등과 같은 많은 응용 분야에서 기능성 경사 복합재(FGM)를 사용하여 필요한 강성을 약화시키지 않으면서 열전도 특성을 향상 시킬 수 있을 것으로 기대된다. 본 논문에서는 M2 공구강과 Cu 간의 FGM 히트 싱크를 가지는 절삭 공구 제작을 위한 기초연구로, M2 와 Cu 를 각각 100:0, 80:20, 60:40, 40:60, 20:80, 0:100 wt% 비율로 사전에 혼합한 금속분말을 분말야금법으로 가압성형 및 소결 제작 하였다. 각 시편의 단면을 광학현미경으로 관찰하여 소결 상태를 분석하였으며, 열전도도, 비열 및 열팽창계수 등 열전달 관련물성을 측정하고 분석하였다.

• 대한기계학회논문집
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• 제10권1호
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• pp.131-137
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• 1986

본 논문에서는 도포하기가 용이한 극성유기물질인 magic ink( $C_{6}$ $H_{5-}$ CH/13+ $C_{6}$ $H_{4}$(C $H_{3}$)$_{2}$+ $C_{4}$ $H_{9}$OH+ $C_{6}$ $H_{12}$ $O_{2}$) 를 Rehbinper 효과가 큰 동에 도포하고, 공구경사각을 변화시켜 매 절삭깊이마다 반복 2차원절삭을 실시하여 절삭기구, 절삭저항의 변화, 전단면의 전단변형율, 전단에너지 및 마찰에너지등의 변화를 상호관련시켜 분석하므로서 절삭성의 향상원인을 규명코저 한다.다.

• 한국정밀공학회지
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• 제23권3호
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• pp.39-46
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• 2006

In this work a dynamic cutting force model in ball end milling of inclined surface is introduced. To represent the complex cutting geometry in ball end milling of inclined surface, workpiece is modeled with Z-map method and cutting edges are divided into finite cutting edge elements. As tool rotates and vibrates, a finite cutting edge element makes two triangular sub-patches. Using the number of nodes in workpiece which are in the interior of sub-patches, instant average uncut chip thickness is derived. Instant dynamic cutting forces are computed with the chip thickness and cutting coefficients. The deformation of cutting tool induced by cutting farces is also computed. With iterative computation of these procedures, a dynamic cutting force model is generated. The model is verified with several experiments.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 춘계학술대회 논문집(한국공작기계학회)
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• pp.346-351
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• 2001

The technique of high speed machining is widely studied in machining field. Because the high efficiency and accuracy in machining can be obtained in high speed machining. Unfortunately the development of tool for high speed machining is not close behind that of machining tool. So in this study, we made 4 types flat end mill for obtaining data according to tool shape. Especially, we concentrated in helix angle and number of cutting edge. First we confirmed cutting condition by several experiments and measuring cutting force, tool life, tool wear and chip shape according to cutting length. In results, we acquired the fact that 45 degree helix angle and six cutting edge tool is suitable for high speed machining.

• 한국공작기계학회논문집
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• 제16권5호
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• pp.191-197
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• 2007

Inclined surface milling in the mould and die industries is one of the most commonly needed cutting process. For the variety and complexity of cutting characteristics in various cutting condition, it is difficult to select a optimal tool path orientation. Especially, when the cutting process becomes unstable, it induces self-exited vibrations, a frequent cause of poor tool life, rough surface finish, damage to the workpiece and the machine tool itself, and excessive down time. The comparative results through FFT analysis in this study provide a guideline for the selection tool path orientation.

• 한국생산제조학회지
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• 제19권2호
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• pp.251-259
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• 2010

It is presented in this study a new efficient intelligent machining strategy, which can be used to remove the uncut volume at the boundary region of curved surfaces caused by cutter interference. The geometric form definitions and recognition of topological features of the surface triangulation mesh are used to generate cutter paths along successive and interconnected steepest pathways, that minimize the cusp height left after flat end milling. In order to machine the uncut volume gradually, the z-map cutter centers are adjusted to avoid cutter interference for the 6 kinds of avoidance types. And then, the generative subsequent paths are sequenced to determine the second step cutter paths for the next uncut volume. For the 2 kinds of test models with convex and concave surface region, the implemented software algorithm is evaluated by investigating the residual swelling of uncut volume for each machining step.

• 한국공작기계학회논문집
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• 제13권2호
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• pp.17-24
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• 2004

In end milling process, undeformed chip thickness and cutting forces vary periodically with phase change of the tool. Recently, a model has been proposed to simulate the shear and friction characteristics of an up-end milling process in terms of the equivalent oblique cutting to this. In the current study, a down-end milling process has been replaced with the equivalent oblique cutting process. And shear and tool-chip friction characteristics variation of SM45C steel has been studied using the end-mills of different helix angles. The specific shear and friction energy consumed with helix angle of $50^{\circ}$ is somewhat larger than those of$30^{\circ}$ and $40^{\circ}$. The specific shear energy consumed is about 76-77% of the specific cutting energy regardless the helix angles.

• 대한기계학회논문집
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• 제19권9호
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• pp.2114-2121
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• 1995

Surface generation model of three types of endmills is introduced to analyse the cutting mechanism of an endmill more accurately. Superposition method is introduced to define the effective cusp including the effects of cutter mark. Through the comparison of three endmills, it is shown that the ball-nose endmill is superior to the ball endmill and the flat endmill for inclined milling process in 3-or 5-axis machining modes. By using the objective function minimizing the machining time, appropriate nose radius is selected for various cutter radiuses and cutter inclination angles.

• 한국CDE학회논문집
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• 제3권3호
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• pp.161-167
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• 1998

Cutting forces in ball-end milling of slanted surfaces are calculated. The cutting area is determined from the Z-map of the surface geometry and current cutter location. The obtained cutting area is projected onto the cutter plane normal to the Z-axis and compared with cutting edge element location. Cutting force is calculated by integration of elemental cutting forces of engaged cutting edge elements. Experiments with various slanted angles were performed to verify the proposed cutting force estimation model. It is shown that the proposed method predicts cutting force effectively for any geometry including sculptured surfaces with cusp marks and surfaces with pockets and holes.

• 한국기계가공학회지
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• 제11권6호
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• pp.88-93
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• 2012

In this study, Machining fine shaft was examined by Lathe. method is proposed to control the thrust force to 0. through relationship between the cutting depth and the thrust force in turning, fine-shaft of less than 0.1mm diameter in turning is confirmed experimentally. also we propose practical expression to control thrust force in turning Through to change the approach angle, optimal tool design would be possible in turning.