• Journal of Mechanical Science and Technology
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• v.17 no.7
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• pp.1044-1053
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• 2003

There are two major differences between the centerless infeed grinding process and the centerless through-feed grinding process. One is an axial movement of workpieces, and the other is that several workpieces are ground simultaneously and continuously by through-feeding. Because of these differences, through-feed ground parts inherently possess not only the roundness error but also the tapering error. The aims of the research reported in this paper are to examine this inherent tapering characteristic and to find the effects of grinding variables (center height angle, regulating wheel tilt angle, and shape of grinding wheel surface). To accomplish the objectives, experiments were carried out using two types of cylindrical workpiece shapes. Also, computer simulations were performed using the 3-D through-feed grinding model.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.6
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• pp.76-82
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• 2000

This paper describes the machining characteristics of cylindrical plunge grinding. The study investigates the process using the current signals of a spindle motor through a hall sensor. Grinding experiments were conducted under various conditions such as wheel speeds, workpiece speeds and infeed rates with a conventional vitrified bonded wheel. Analyzing the current signal of the spindle motor, a relationship between current signals and the metal removal rate in terms of the in(red rate is induced. It was also shown that a hall sensor has similar capabilities in evaluation of grinding behavior compared to the AE signals, which are useful far monitoring the grinding process.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.4
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• pp.25-31
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• 2003

A computer simulation model for investigating a two-dimensional (2-D) rounding mechanism in a centerless grinding process is described. This model includes the interference phenomena and the concept of machining elasticity. Since initial contact points are used as a reference, the result of this simulation is not affected by the location of the reference circle center and the radius of the reference circle. Also, details of the machining factor are studied by using process variables (grinding wheel speed, wheel specification, workpiece speed, dressing condition, etc.). The effect of the threshold grinding force on the size of ground workpiece is investigated. For the verification of this method, simulation results are compared with the experimental work.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.28-32
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• 1995

Bacause the chatter vibration is a main factor to damage on the quality and integrity, The cure is required peticurity in cykinderical plunge grinding. The chatter vibration relatied with wheel speed, workpiece and infeed rate. Therefore, we expressed more credible normal signal and chatter signal Pattern in accrdiance with wheel speed and acquired RMS signal of the accelerrometer. In thos study, after finding the chatter pattern, we applied two parameters, standard deviation and Kurtosis, to Neural Network.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.5
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• pp.40-46
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• 2017

A plasma gas control apparatus for semiconductor plasma etching processes securely holds a cathode for forming a plasma, confines the plasma during the plasma etching process, and discharges gas after etching. It is a key part of the etching process. With the advancement of semiconductor technology, there is increasing interest in parts for semiconductor manufacturing that directly affect wafers. Accordingly, in order to replace the plasma gas control device with a CVD-SiC material superior in mechanical properties to existing SiCs (Sintered-SiC, RB-SiC), a study on the grinding characteristics of CVD-SiC was carried out. It is confirmed that the optimal grinding condition was obtained when the result table feed rate was 2 m/min and the infeed depth was $5{\mu}m$.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.260-260
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• 2004

연삭 가공은 대직경 반도체 웨이퍼의 경면 가공, 산업용 정밀 부품, 광학 분야의 고정밀급 렌즈 등 여러 산업 분야의 각종 정밀 부품의 마무리 공정에 적총되어 제품의 질을 좌우하는 필수적인 공정이라 할 수 있다. 이러한 연삭 가공은 높은 치수 정밀도와 양호한 표면 거칠기 및 제품의 형상을 동시에 만족시킬 수 있는 가공 기술로서 , 대직경 웨이퍼 생산에 있어서, 고정밀ㆍ고품위의 웨이퍼를 양산하는데 적합한 기술로 인식되고 있다.(중략)