• 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 Ceramic Society
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• v.47 no.4
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• pp.290-295
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• 2010

This study has been focused on properties of mirror surface grinding technology by ELID(Electrolytic In-process Dressing) for structural ceramics using in high precision structural parts as like semi-conductor manufacturing processes. The experimental studies have been carried out to get mirror surface for grinding of structural ceramics, SiC, $Al_2O_3$ and AlN. Grinding process of the ceramics is carried out with varying mesh type, depth of cut and feed rate using diamond wheel. The machining result of the surface roughness and condition of ground surface, have been analyzed by use of surface roughness tester, SEM, AFM and three dimensional surface profiler measurement system.

• International Journal of Precision Engineering and Manufacturing
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• v.1 no.1
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• pp.127-132
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• 2000

A highly efficient mirror surface grinding technology has been developed for hard and brittle materials various metal materials, by employing the ELID (electrolytic in-process dressing) grinding method using metal bonded grinding wheels. In this research, some typical applications of ELID-grinding for cylindrical grinding are introduced and the mirror grinding characteristics are investigated. Good results are obtained in the grinding of ceramics and tungsten carbide.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.1 s.178
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• pp.97-104
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• 2006

ELID(Electrolytic In-process Dressing) grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials. A polishing process is also required for elimination of scratches present on ELID grinded surfaces. MAP(Magnetic Assisted Polishing) has been used as polishing method due to its high polishing efficiency and to its resulting in a superior surface quality. This study is describing an effective fabrication method combining ELID and MAP of nano-precision mirror grinding for glass-lens molding mould. It also presents some techniques for achieving the nanometer roughness of the hard metals, such as WC-Co, which are extensively used in precision tooling material.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.6
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• pp.1486-1496
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• 1993

The diamond wheel with superabrasive is required for mirror-like surface grinding of brittle materials. But the conventional dressing mothod can not apply to the diamond wheel with superabrasive. Recently electrolytic dressing method was developed for cast-iron bonded diamond wheel with superabrasive. This technique can take replace of lapping and polishing. Using the electrolytic dressing, the surface roughness of workpiece was improved largely and grinding force was very low and the continuity of the grinding force was also very improved. In this study, the purpose is the realization of mirror-like surface grinding of ferrite with electrolytic dressing of metal bonded diamond wheel. For application of ultraprecision grinding for brittle material, superabrasive wheel, air spindle and inprocess electrolytic dressing were used. In addition, the effects of pick current and pulse width on ground surface were investigated, and the suitable dressing conditions for ferrite were found out.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.459-464
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• 2000

In this paper, it verifies the relationships between wheel velocity and surface roughness with the mirror surface grinding using electrolytic in-process dressing (ELID). In the general, as wheel velocity is high, surface roughness is better on the base of grinding theory. However, the relationships between wheel velocity and surface roughness is undefined due to the effect of electro-chemical dressing and the characteristics of materials. According to above relationships, ELID grinding experiment is carried out by following the change of wheel velocity. As the result of this study, it is found that surface roughness is not better as linearly as the increase of wheel velocity, but the limit of wheel velocity exists according to the characteristics of materials. Also, in contradiction to the present trend of high wheel velocity of manufacturing system for high surface integrity, it is able to expected to the base on the development of new ultra precision grinding method with the practicality of mirror surface grinding using ELID grinding method.

• International Journal of Precision Engineering and Manufacturing
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• v.8 no.2
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• pp.38-43
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• 2007

This paper describes ultrasonically assisted grinding used to obtain a glossy surface quickly and precisely. High-quality surfaces are required for plastic injection molding dies used in the production of plastic parts such as dials for cellular phones. Traditionally, in order to finish the dies, manual polishing by a skilled worker has been required after the machining processes, such as electro discharge machining (EDM), which leaves an affected layer, and milling, which leaves tooling marks. However, manual polishing causes detrimental geometrical deviations of the die and consumes several days to finish a die surface. Therefore, a machining process for finishing dies without manual polishing to improve the surface roughness and form accuracy would be extremely valuable. In this study, a 3D positioning machine equipped with an ultrasonic spindle was used to conduct grinding experiments. An electroplated diamond tool was used for these experiments. Generally, diamond tools cannot grind steel because of excessive wear as a result of carbon atoms diffusing into bulk steel and chips. However, ultrasonically assisted grinding can achieve a fine surface (roughness Rz of $0.4{\mu}m$) on die steel without severe tool wear. The final aim of this study is to realize mirror surface grinding for injection molding dies without manual polishing. To do this, it is necessary to fabricate an electroplated diamond tool with high form accuracy and low run-out. This paper describes a tool-making method for high precision grinding and the grinding performance of a self-electroplated tool. The ground surface textures, tool performance and tool life were investigated A ground surface roughness Rz of 0.14 um was achieved Our results show that the spindle speed, feed rate and cross feed affected the surface texture. One tool could finish $5000mm^2$ of die steel surface without any deterioration of the ground surface roughness.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.04a
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• pp.970-976
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• 1997

The ultra-precision machining is widely used for final machining process of precision parts, so in this study, mirror surface finishing systems using the micro abrasive film, one of ultra-precision machining method, have to examine mirror surface characteristics of the cylindrical workpiece(SM45) such as surface roughness, workpiece removal and evaluated under the condition varing film feed rate, applied pressure, grinding speed after fixing other condition. It was found that varrious machining condition have significant influences on workpiece removal, surface roughness.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.6
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• pp.45-51
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• 1996

Silicon wafers are required to be finished under the roughness of nanometer order for the subsequent chip fabrication processes. Recently, the finish grinding techniques have been researched for the improvement of accuracy and surface roughness simultaneously. Among them, the grinding technique using fine abrasive has been known as an easily accessible method. However, the manufacture of the fine grit grinding wheel has been very difficult because of the coherence of the grits. In this paper, the development of the ultrafine grit silica($SiO_2$) grinding wheel by the combination of the binder coating and the vacuum forming techniques is reported. And, the mechanochemical removal effects of the grinding conditions are discussed. Finally, a successful result of Ra O.4nm. Rmax 4nm in the ground surface roughness of a 6 inch silicon wafer was achieved.

• Journal of the Korean Ceramic Society
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• v.46 no.1
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• pp.102-107
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• 2009

This study has been focused on an effective surface finishing method combining ELID (ELectrolytic In-process Dressing) and MAP (Magnetic Assisted Polishing) for the nano-precision mirror grinding of glass-lens molding mould. ELID grinding is an excellent technique for mirror grinding of various advanced metallic or nonmetallic materials. A polishing process is also required for elimination of scratches present on ELID grinded surfaces. MAP has been used as polishing method due to its high polishing efficiency and superior surface quality. It also presents some techniques for achieving the nanometer roughness of the hard material such as WC-Co, which are extensively used in precision tooling material.