• Journal of the Korean Society of Manufacturing Process Engineers
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• v.3 no.1
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• pp.45-51
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• 2004

In this paper, the relationship between the mechanical properties of alumina abrasives and grinding performance was investigated. Micro vickers hardness and fracture strength of all abrasives used in this study were measured. The grinding experiments were earned out with alumina grinding wheels made by various kinds of alumina abrasives including 32A, WA, ART, ALOMAX, and RA. The performance of such grinding wheel for grinding SKD11 was evaluated by specific grinding energy, grinding-ratio, and surface roughness. The grinding wheels composed by the harder abrasives and the lower fracture strength abrasives showed better grinding performance.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.319-323
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• 2005

As a new approach to analyze grinding energy, this paper introduces a specific grinding energy model based on the average grain. Using this model, grinding characteristics such as specific grinding energy of SM45C were investigated with changing variables such as grain size, workpiece velocity(v) and apparent depth of cut(Z) in down-surface grinding. From the experimental results, the specific grinding energy decreases as the maximum undeformed chip thickness increases. And also the specific grinding energy increases as the grit size increases.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.155-162
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• 2000

전해 인프로세스 드레싱(ELID)의 응용기술로써 간헐적 드레싱(ELID II) 및 무전극 드레싱(ELID III)이 원통내면 마무리 연삭에 이용되고 있다. 주철본드(CIB-D) 및 메탈레진본드 다이아몬드 숫돌(HRB-D)이 이 방식들에 사용되고 있다. 경면 가공에 있어서 이 두방식은 미립의 숫돌이용으로 일반연삭기에 정밀부속 장치의 보완없이 이용될 수 있다. ELID II 연삭에서 CIB-D숫돌은 파이프 형상의 전극에 의하여 간헐적으로 드레싱되고, 반면에 MRB-D 숫돌은 인프로세스 드레싱 되며 전극은 필요로 하지 않는다. 본 연구에서는 ELID II 및 ELID III 방식에 있어서, 연삭조건 및 연삭입자크기에 대한 연삭특성을 비교검토 하였다. 그 결과, ELID II, III방식 공히 대단히 작은 표면거칠기를 갖는 경면이 얻어짐을 확인하였다.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.16-21
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• 2004

As a new approach to analyze grinding energy, this paper introduces a specific grinding energy model based on the average grain. Using this model, grinding characteristics such as radial and tangential forces, specific grinding energy of SM45C were investigated altering grinding variables such as workpiece velocity(v) and apparent depth of cut(Z) in down-surface grinding. From the experimental results, there is no significant difference between the radial, tangential forces and vertical. horizontal forces because of small contact angle between wheel and workpiece. The specific grinding energy decreases as the maximum undeformed chip thickness increases. But, there is much difference between the specific grinding energies of the existing and the proposed model.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.4
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• pp.61-68
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• 2005

As a new approach to analyze grinding energy, this paper introduces a specific grinding energy model based on the average grain. Using this model, grinding characteristics such as radial and tangential forces, specific grinding energy of SM45C were investigated with changing grinding variables such as workpiece velocity(v) and apparent depth of cut(Z) in down-surface grinding. From the experimental results, the specific grinding energy decreases as the maximum undeformed chip thickness increases. And there is no significant difference between the specific grinding energies of the existing and the proposed model.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.2
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• pp.241-251
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• 1988

The purpose of this paper is to evaluate fracture strength of WA-vitrified and resinoid bond grinding wheels by means of acoustic emission. The paper conducts tension test, compression test, splitting tensile test and bending test with AE measuring system. These tests have been carried out in accordance with the grain sizes and grades of grinding wheels. The fracture strength of grinding wheels is evaluated by the clarification of biaxal fracture criterion of Babel and Sines. It clarifies the influence of factors of grinding wheel upon AE characteristics and evaluates the predictability of life of grinding wheels and the perception of fracture.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.2
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• pp.30-36
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• 2007

In order to estimate the maximum undeformed chip thickness in grinding operation, it is necessary to obtain the successive cutting point spacing. In the past it was obtained by experiments. In this paper, the average successive cutting point spacing has been obtained using the given grinding input conditions and it is possible to estimate the maximum undeformed chip thickness without using any experimentally obtained data. The validity of the proposed analysis has been verified based on two sets of grinding scratch tests using WA and CBN grinding wheels.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.28-31
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• 2002

This paper compared the surface roughness with variables before development of centerless grinding using far ferrule machining. In this paper, theoretical surface roughness is obtained from variables such as mesh number, rate of concentration of grinding wheel, wheel rotation of work-piece etc., and optimum condition of machining is selected. For satisfaction the technical side and economical side, centerless grinding using fur ferrule machining should be designed more than #600, 18.8% rate of concentration of grinding wheel, 1440rpm wheel rotation outwork-piece.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.12
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• pp.2962-2969
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• 1993

Recently, a study on the mirror-like surface grinding of brittle materials is active and as branch of these study, new dressing method for superabrasive wheel, electrolytic inprocess dressing(Elid) was developed. Using Elid, the mirror-like surface of brittle material can be generated without polishing or lapping process. In the future, Elid grinding will take important place in industry. But so far the analysis on Elid grinding was not quantitative but qualitative. In this study, The purpose is the quantitative analysis on Elid grinding by computer simulation, For computer simulation, the mean and the variance of the abrasive distribution were measured by tracing of the grinding wheel with stylus in transverse direction in the case of respective dressing current condition. This measurement result in a density distribution of abrasive by mathematical formulation using statistical method. The prediction of the surface roughness in Elid grinding was based on this density distribution.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.3
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• pp.105-110
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• 2020

Alumina, a typical ceramic material used for semiconductors and display parts, is the subject of research and development efforts for mineral material processing. Alumina is extremely difficult to process since it is brittleness to either fine ceramics material. We have studied the shape of diamond particles and their use in machinability for alumina processing. Our study was carried out under various processing conditions, including cutting speed, table speed, and the surface roughness of the work piece. We also analyzed the wear characteristics of the tool by total cutting.