• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1996년도 춘계학술대회 논문집
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• pp.149-154
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• 1996

The applicability of a new method, termed the whirling motion concept, for the iprovement of the surface finish in milling three-dimensional sculptured surfaces has been investigated. A method for implementing this concept on conventional NC machines that utilize a suitably configured attachment has been proposed. The tool path equation for the ball-end milling process, based on the Surface-Shaping system, has been obtained. Both results of the computer simulation and the experiment verified the computer simulation and the experiment verified the proposed approach.

• 한국정밀공학회지
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• 제16권11호
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• pp.197-203
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• 1999

Increasing demands on precision machining have necessitated the tool to move not only position error as small as possible, but also with smoothly varying feedrates. Because of the lack of accurate and efficient algorithms for generation of 3-dimensional lines and circles, a full accomlishment for available machine tool resolution is generally unavailable. In this paper, a reference-pulse type 3-axis PC_NC milling system is developed for the precision machining of complex shapes in 3-dimensional space. Three AC servomotors are used as the actuator instead of the hand wheel to operate a 3-axis milling machine under the same mechanical structure. A PC is used to handle the control signal calculation for various types of motion command. To achieve the synchronous 3-axis motion, a real-time reference-pulse 3-dimensional linear and circular interpolator based on the intersection criteria is developed in software. The performance test via computer simulation and actual machining have shown that the PC-NC milling system is useful for the machining of arbitrary lines and circles in 3-dimensional space.

• Tribology and Lubricants
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• 제26권6호
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• pp.329-335
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• 2010

Recently, the End-milling processing is needed the high-precise technique to get a good surface roughness and rapid time in manufacturing of precision machine parts and electronic parts. The optimum surface roughness has an effect on end-milling working condition such as, cutting direction, spindle speed, feed rate and depth of cut, and so on. It needs to form the correlation of working conditions and surface roughness. Therefore this study was carried out to presume of surface roughness on end-milling working condition of Al7075 by regression analysis. The results was shown that the coefficient of determination($R^2$) of regression equation had a fine reliability of 87.5% and nonlinear regression equation of surface rough was made by multiple regression analysis.

• 한국생산제조학회지
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• 제5권3호
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• pp.73-79
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• 1996

In this paper present a new technique (strain-telemetering)for detection of coated tool failure in face milling processes. In the cutter body the strain signals received fro the transmitter is transformed in to frequency modulation(FM) signals in face milling processes. A receiver which is place near by the Vertical milling machine receives the FM signals, then the signals will be sent to a computer which determines whether th tool is failure. And machined surface of workpiece is detected by the SEM. In this paper, A on-line monitoring of the tool failure detection system based on the strain -telemetering apparatus has bee represented.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1822-1827
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• 2003

End-milling have been used widely in industrial system because it is effective to a material manufacturing with various shape. Recently the end-milling processing is needed the high-precise technique with good surface roughness and rapid time in precision machine part and electronic part. The optimum surface roughness has an effect on end-milling condition such as, cutting direction, spindle speed, feed rate and depth of cut, etc. Therefore this study was carried out to presume for mutual relation of end-milling condition to get the optimum surface roughness by regression analysis. The results shown that coefficient of determination($R^{2}m$) of regression equation has a fine reliability over 80% and regression equation of surface rough is made by regression analysis.

• 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.

• 한국생산제조학회지
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• 제25권4호
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• pp.271-280
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• 2016

Predicting cutting forces in machine tools is essential to productivity improvement and process control in the manufacturing field. Furthermore, milling machining is more complicated than turning machining. Therefore, several studies have been conducted previously to simulate milling forces; this study aims to simulate the cutting forces in milling machines using multi-layered neural networks. In the experiments, the number of layers in these networks was 3 and 4 and the number of neurons in the hidden layers was varied from 20 to 200. The root mean square errors of simulated cutting force components were obtained from taught and untaught data for the various neural networks. Results show that the error trends for untaught data were non-uniform because of the complex nature of the cutting force components, which was caused by different cutting factors and nonlinear characteristics coming into play. However, trends for taught data showed a very good coincidence.

• Advances in Computational Design
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• 제5권1호
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• pp.13-34
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• 2020

As small size and complex metal machining components demand increases, cutting processes in microscale become necessary. Ball-end milling is a commonly used finishing process, which nowadays can be applied in the microscale size. Surface quality and dimensional accuracy are two basic parameters that affect small size components in their assembly and functionality. Thus, good quality can be achieved by optimizing the cutting conditions of the procedure. This study presents a 3D simulation model of ball-end milling in microscale developed in a commercial CAD software and its optical and computing results. These carried out results are resumed to surface topomorphy, surface roughness, chip geometry and cutting forces calculations that arising during the cutting process. A great number of simulations were performed in a milling machine centre, applying the discretized kinematics of the procedure and the final results were compared with measurements of Al7075-T651 experiments.

• 한국콘텐츠학회논문지
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• 제21권3호
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• pp.602-608
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• 2021

임상에서 사용되는 Co-Cr 합금과 도재 간의 접착 강도를 비교하기 위해 대조군으로 전통적인 주조(Casting) 방법, 실험군으로 Milling(Milling group), SLM(3d printing group) 시편을 제작하여 금속과 도재(ceramic) 간의 접착 강도를 비교 하였다. 합금과 도재간의 접착강도를 측정하기 위해 universal testing machine를 이용하여 3점 굴곡 시험을 시행하고, 결합강도 측정 후 금속-도재간의 계면을 관찰하였다. 금속-도재(ceramic) 간의 실험 결과 casting group 53.59 MPa, milling group 45.90 MPa, 3d printing group 58.34 MPa의 결과값을 보였고, 통계적으로 유의성은 없었다. 파절양상은 두 집단 시편의 대부분이 복합 파절양상(mixed failure)을 보였다. 본 연구는 3D 프린팅로 제작된 합금으로 합금-도재의 결합 강도값을 측정하였을 때 임상적으로 적용 가능한 수치를 보여 주었다.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 1998년도 제27회 춘계학술대회
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• pp.77-82
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• 1998

The Part of slot on rotary compressor which plays an important part of the reliability and performance is studied on machinability and the wear characteristics for the specimen made by sand mold and permanent mold. The experiment are used the face cutter of milling machine which make the processing surface like broaching process and rollblock wear test machine. Permanent-mold casting iron is not affected by variation of RPM of milling machine, but sand-mold cast-iron is improved to increasing RPM. Also sand-mold casting iron shows superior wear characteristic to permanent-mold casting iron. This results from harder matrix of pearlite structure and self-lubrication characteristics of graphite. And wear particles in tested oil show shape and size similar to severe wear particles of oil taken from rotary compressor. The material and surface condition of slot play important part of the reliability and performance.