• 대한환경공학회지
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• 제22권6호
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• pp.1139-1148
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• 2000

산업 폐기물 중 다량으로 발생하는 제강슬래그의 재활용을 위하여 -14/+24mesh 정도 크기의 슬래그를 미분말로 분쇄시 최적 조건을 조사하고 경제적인 분쇄조건을 확립하기 위하여 요구되는 동력을 산출하였다. 이를 위한 분쇄조건으로 ball mill의 회전속도, 분쇄시간, ball의 충진량, 시료의 충진량과 크기 등을 선정하였고 이에 대한 분쇄효율을 산출하였다. 본 연구에서는 임계회전속도의 79% 정도에 해당되는 값이 최적의 회전속도인 것으로 조사되었다. 분쇄시간에 따른 분쇄정도는 일반적으로 시간이 증가함에 따라 증가하는 것으로 나타났지만 분쇄 초기에 비해 분쇄가 더 진행될수록 분쇄효율은 감소하는 것으로 나타났다. Ball의 충진율은 mill내부 용량의 50%인 경우에 최척의 분쇄효율을 보였고, 시료의 충진량과 크기에 따른 입도초사 실험 에서는 시료의 충진량이 적고 원시료의 크기가 작을수록 분쇄정도는 증가하였다. 위의 결과에 의해 Bond의 식을 사용하여 동력효율을 계산한 결과 분쇄시간이 길수록 그리고 회전속도가 최적인 조건에서 동력효율이 가장 크게 나타나고 있음이 관찰되었다.

• 한국정밀공학회지
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• 제11권5호
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• pp.42-55
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• 1994

Presently, abrasive processing is on eof several methods for cutting and grinding brittle materials, and high quality in dimensional accuracy and surface roughness are often required as a structural components, therefore most of them has to be ground. In manufacturing of tungsten-carbide components, grinding by diamond wheel is usually adopted in order to provide configurational and dimensional accuracy to the components. The present study proposes the experi- mental research of optimum condition to the high quality surface grinding of the WC-Co material using diamond abrasive wheel in order to minimize the damage on the ground surface and to pursue the precise dimension by conventional grinding machine. Brief investigation is carried out to decrease the dressing is constant, theoretical grinding effect such as machining precision is changed according to the speed of workpiece. Accordingly, normal and tangential grinding forces, which are Fn, Ft were analyzed for the machining processes of WC-Co material to obtain optimum grinding conditions, 3-point bending test is carried out to check machining damage on the ground surface layer, which is one of sintered brittle materials.

• 대한기계학회논문집
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• 제18권3호
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• pp.785-792
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• 1994

Ferrite is widely used in the material of magnetic head, but is difficult of grinding because of their brittleness and hardness. Therefore, diamond wheel with superabrasive is required for surface grinding of this brittle material. But the conventional dressing method can not apply to the diamond wheel with superabrasive. In this study describes a newly proposed method for carrying out effective inprocess dressing of diamond wheel with superabrasive. Using the IEDD the surface roughness of workpiece was improved and grinding force was very low. Resently IEDD is good method to obtain the efficiency grinding and surface grinding of brittle materials.

• 한국세라믹학회지
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• 제56권2호
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• pp.153-159
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• 2019

In this study, fly ash of a fluidized bed boiler produced in a power plant was stabilized by hydration and carbonation reaction. Then, each raw material was pulverized by two kinds of grinding equipment (Planetary mills and pot mills); the degree of grinding and the agglomeration behavior were observed. It was found that there were changes of specific surface area and particle size distribution according to grinding time. The surface of the raw material was observed using an optical microscope. As a result, agglomerates of about 75 ㎛ or more due to electrostatic phenomenon were formed as the grinding time became longer; it was confirmed that the crushing efficiency slightly increased with use of antistatic agent.

• 한국생산제조학회지
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• 제8권6호
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• pp.16-25
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• 1999

In recent years, grinding techniques for precision machining of brittle materials used in die, model and optical parts have been improved by using superfine abrasive wheel and precision grinding machine. The completion of optimum dressing of superfine abrasive wheel makes possible the effective precision grinding of die steel(STD-11). In this study, a new system and the grinding mechanism of optimum in-process electrolytic dressing were proposed. This method can carry out optimum in-process electrolytic dressing of superfine abrasive wheel. Therefore, the optimum in-process electrolytic dressing is a good method to obtain the efficiency and mirror-like grinding of STD-11.

• 한국생산제조학회지
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• 제7권5호
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• pp.29-37
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• 1998

In recent years, grinding techniques for precision machining of stainless steel used in shaft, screw parts and clear value have been improved by using the superabrasive wheel and precision grinding machine. The completion of optimum dressing of superabrasive wheel makes possible the effective precision grinding of stainless steel. However, the present dressing system cannot have control of optimum dressing of the superabrasive wheel. In this study, a new system and the grinding mechanism of optimum in-process dressing of superabrasive wheel. Therefore, the optimum in-process electrolytic dressing is a good method to obtain the efficiency and mirror-like grinding of stainless steel (STS304)

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.516-519
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• 2004

As the optical communication industry is developed, the demand of optical communication part is increasing. ZrO$_2$ ceramic ferrule is very important part which can determines the transmission efficiency and information quality to connect the optical fibers. In general ZrO$_2$ ceramic ferrule is manufactured by grinding process because the demands precision is very high. And the co-axle grinding process of ZrO$_2$ ceramic ferrule is to make its concentricity all of uniform before centerless grinding. This paper deals with the analysis of the process parameters such as grinding wheel speed, grinding feedrate and regulating wheel speed as influential factors, on the concentricity and surface finish developed based on Taguchi's experimental design methods. Taguchi s tools such as orthogonal array, signal-to-noise ratio, factor effect analysis, etc. have been used for this purpose optimal condition has been found out. Thus, if possible be finding highly efficient and quality grinding conditions.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.747-748
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• 2013

• 오토저널
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• 제15권2호
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• pp.130-143
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• 1993

Engineering ceramics have some excellent properties as the material for the mechanical components. It is, however, very difficult to grind ceramics with high efficiency because of their high strength, hardness and brittleness. In this paper, experiments are carried out to obtain the effect of "In-process dressing" to grind the Engineering ceramics with high efficiency. To save running time for dressing process and obtain restraint effect of diamond grain wear, "In-process dressing" system using WA stick type honing stone is proposed. Representative Engineering ceramics, such as AI$_{2}$O$_{3}$, Si$_{3}$N$_{4}$, are ground with diamond wheel. Also bending strength test is carried out to check upward tendancy of mecahnical properties as the result of machining defact restraint through the grinding machining method using "In-process dressing" process. Some results obtained in this study provide useful information to attain the high efficiency grinding and the high mechanical properties of Engineering ceramics.rties of Engineering ceramics.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2011년도 춘계학술대회 논문집
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• pp.701-702
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• 2011