• 한국정밀공학회지
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• 제10권1호
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• pp.147-152
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• 1993

The lapping characteristics of single crystal diamond are studied by considering the crystallographic anisotropy. It is introduced for lapping method to identify crystallographic orientantion by the X-ray diffraction and to measure lapping force ratio, lapping temperature and lapping wear. Diamound bonded wheels are used for lapping under dry condition. On the lapping {110} and {100} planes, it shows remarkable crystallographic anistropy. The lapping force ratio, temperature and wear become gerater with sliding direction along the <100> than along <110>. The results also show that the wear of diamond is influenced by mechanical work(tangential lapping force * lapping distance) as well by lapping speed.

• 한국공작기계학회논문집
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• 제12권3호
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• pp.1-7
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• 2003

In-process Electrolytic Dressing is a lapping method using electrolysis. This technology provides dressing to CIB-Diamond Lapping wheels during the lapping process for continuous protrude abrasive from super-abrasive wheels. so loading and glazing are disappeared apparently. Ultra-precision lapping of the machinable commies will be studied in the viewpoint of In-process Electrolytic Dressing. For ultra-precision lapping, need to develop an ultra-precision lapping system suitable metal bonded diamond wheel, and appropriate condition of u10a-precision lapping machining.

• 한국산업융합학회 논문집
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• 제5권4호
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• pp.367-372
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• 2002

Experimental study was conducted for lapping process after WEDMed specimen. In order to decide the lapping depth of the specimen, the number of the grain size was increased from 400, 600 to 800 to obtain the better surface. Observation of scanning electron microscope, hardness test, surface roughness test and energy dispersive spectrum(EDS) analysis were used for this experimental study. From the comparison and analyses of the results of between the wire-cut electrical discharge machining and the lapping, the following results were obtained. The surface roughness after lapping was found to be improved as increasing the number of lapping process like 1st, 2nd, 3rd lapping and the number of grain size such as 400, 600, 800. The surface hardness after increasing the lapping depth of the specimen was slowly increased. It was found that after 3rd lapping process the hardness was reached the hardness of original base material. It was found that the small amount of coating components within 3% was remained after the 1st lapping process, compared to that approximately 16% after WEDM process.

• 한국기계가공학회지
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• 제5권4호
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• pp.21-26
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• 2006

Characteristics of texture and groove precision lapping plate are experimentally investigated by Measuring frictional forces. It is found that the frictional coefficient decreases as the embedding of diamond particles progresses. The groove precision lapping plate with concentric micro-channels indicates superior capability in embedding micrometer-sized diamond particles and uniformity in diamond embedding compared with the texture precision lapping plate with a series of circular micro-channels.

• 대한기계학회논문집
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• 제18권4호
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• pp.856-865
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• 1994

Cylindrical fine-ceramics, $Al_{2}O_{3}$, was lapped on its outer surface by vibrational lapping unit manufactured in the laboratory. Cylindrical lapping of fine-ceramics is necessarily be characterized and optimized because its process as other finishing methods is time-spending and, so, inefficient one, and because it is very complicated and random process affected by numerous factors in itself and in its environment. In this study, an efficient experimental approach, experimental design method, was used to analyze characteristics of the cylindrical lapping of fine-ceramics, $Al_{2}O_{3}$, and response surface methodology(RSM) to find out the optimal variables combination for the maximum improvement of surface roughness($R_a$). From the final surface roughness point of view in the given lapping conditions, a stationary point or optimal lapping conditions as well as the possible maximum improvement of surface roughness($R_a$) was predicted.

• 한국생산제조학회지
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• 제9권5호
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• pp.34-39
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• 2000

Application of ceramics has grown considerably due to significant improvement in their mechanical properties such as light weight, chemical stability and superior wear resistance. Despite these character, the use of ceramics has not increased because of poor machinability. The method of using of super-abrasives metal bond wheel was proposed. But it is difficult that super-abrasives metal bond wheel can be dressed. Recently, the technology of in-process electrolytic dressing is developed to solve this problem. If this method is applied, loading and glazing are disappeared apparently. The aim of this study is to determine the machining characteristics in terms of lapping wheel speed, machining time, pressurized weight to the workpiece and peak current using in-process electrolytic dressing applied to the CIB-diamond lapping wheel to achieve ultra-precision lapping machining technique.

• 한국정밀공학회지
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• 제29권12호
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• pp.1285-1289
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• 2012

This study has been focused on application of ELID lapping process for mirror-surface machining of sapphire wafer. Sapphire wafer is a superior material with optic properties of high performance as light transmission, thermal conductivity, hardness and so on. High effective surface machining technology is necessary to use sapphire as various usages. The interval ELID lapping process has been set up for lapping of the sapphire material. According to the ELID lapping experimental results, it shows that 12.5 kg of load for lapping is most pertinent to ELID lapping. the surface of sapphire can be eliminated by metal bonded wheel with micron abrasives and the surface roughness of 60 nmRa can be gotten using grinding wheel of 2,000 mesh in 4.5 um, depth of cut. In this study, the chemical experiments after ELID grinding also has been conducted to check chemical reaction between workpiece and grinding wheel on ELID grinding process. It shows that the chemical reaction has not happened as the results of the chemical experiments.

• 한국정밀공학회지
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• 제18권9호
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• pp.18-24
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• 2001

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.537-542
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• 2004

Machinble 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. Lapping used diamond slurry and lapping by in-process electrolytic dressing is developed to solve this problem. On this paper, a comparative study of processing ability of lapping used diamond slurry and lapping by in-process electrolytic dressing.

• 반도체디스플레이기술학회지
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• 제12권4호
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• pp.9-13
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• 2013

Lapping is a very complicated and random process resulting from the variation of abrasive grains in its sizes and shapes and from the numerous factors having an effect on the process quality. This paper presents a study of a $2^4$ full factorial experimental design and analysis to optimize surface quality in lapping operation. The optimization of the factors to obtain minimum surface roughness was carried out by incorporating effect plots, main effect plots, interaction plots, analysis of variance(ANOVA), surface plots, and contour plots. The statistical design experiments, designed to reduce the total number of experiments required, indicated that, within the selected conditions, all the parameters influenced at a significance level of 5%. In addition, some of the possible interactions between these parameters also influenced the lapping process, especially those that were of third order. A regression model was suggested and fitted the experimental data very well.