• 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 Powder Materials
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• v.20 no.4
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• pp.297-301
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• 2013

Mirror surface machining for large area flattening in the display field has a problem such as a tool wear and a increase in machining time due to large area machining. It should be studied to decrease machining time and tool wear. In this paper, multi-tool machining method using a PCD tool and a SCD tool was applied in order to decrease machining time and tool wear. Machining characteristics (cutting force, machined surface and surface roughness) of PCD tool and SCD tool were evaluated in order to apply PCD tool to flattening machining. Based on basic experiments, the PCD/SCD multi-tool method and the SCD single-tool method were compared through surface roughness and machining time for appllying large area mold machining.

• 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.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.82-88
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• 1997

In this paper, the development of a precision CNC lathe prototype for mirror surface machining is presented. To obtain high precision machining accuracy, a hydrostatically supported precision spindle and a sliding guideway with turcite pad are adopted as the motion elements. The machining accuracy of the prototype machine, and the motional accuracy of its motion elements are tested and evaluated to confirm the validity of the application of these elements on the prototype. The hydrostatic spindle shows 0.09 .mu. m of rotational accuracy and the guideway shows about 0.8 .mu. m/170mm of horizontal straightness. The sur- face roughness of cupper and aluminium cylinder machined by the prototype machine with diamond tool are 0.07 .mu. m and 0.10 .mu. m Rmax respectively. From these results, it is verified that the prototype lathe is avail- able for high precision machining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.19-20
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• 2010

• Journal of the Korean Society for Precision Engineering
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• v.23 no.5 s.182
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• pp.44-50
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• 2006

This paper describs about the technique of ultra-precision machining for an infrared(IR) camera aspheric mirror. A 200 mm diameter aspheric mirror was fabricated by SPDTM(Single Point Diamond Turning Machine). Aluminum alloy as mirror substrates is known to be easily machined, but not polishable due to its ductility. Aspheric large reflector without a polishing process, the surface roughness of 5 nm Ra, and the form error of ${\lambda}/2\;({\lambda}=632.8\;nm)$ for reference curved surface 200 mm has been required. The purpose of this research is to find the optimum machining conditions for cutting reflector using Al6061-T651 and apply the SPDTM technique to the manufacturing of ultra precision optical components of Al-alloy aspheric reflector. The cutting force and the surface roughness are measured according to each cutting conditions feed rate, depth of cut and cutting speed, using diamond turning machine to perform cutting processing. As a result, the surface roughness is good when feed rate is 1mm/min, depth of cut $4{\mu}m$ and cutting speed is 220 m/min. We could machined the primary mirror for IR camera in diamond machine with a surface roughness within $0.483{\mu}m$ Rt on aspheric.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.57-60
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• 1995

Recently, ELID (electrolytic in-process dressing) grinding technique is developed. It is possible to make a efficient precision machining of hard materials such as ceramic hard metals, and quenched steels. This paper deals with some typical applications of ELID-grinding for cylindrcal machining. The significant advantages, performance and characteristics on mirror surface grinding for external surface are described.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.14 no.2
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• pp.83-90
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• 2005

A mirror cam mechanism a kind of conjugate cam mechanism consists of two cams, two rollers, and two links. Since profiles of two mirror cam are identical, a simultaneous machining of two cams is achievable. Some machining errors on cam profiles do not result in the internal acting force, which often causes problems in high speed cam mechanism between two links. Also, since angular accelerations of two links are same, the internal acting force by the difference of the angular accelerations does not occur in the mechanism. Thus the mirror cam mechanism is very useful in high speed machinery. This paper studies a design method as well as a machining method, and develops an exclusive CAD/CAM software for mirror cam profiles. The developed CAD/CAM software is applied to a typical mirror cam mechanism and a mock-up equipment is built in order to test the machinism mirror cm. Experimental investigations show that the contact between cam surface and roller surface according to cam rotation agrees well with the simulation on the developed CAD/CAM software.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.444-447
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• 2005

This paper is described about the technique of ultra-precision machining for a infrared camera aspheric mirror. A 200 mm diameter aspheric mirror was fabricated by SPDTM. Aluminum alloy as mirror substrates is known to be easily machined, but not polishable due to its ductility. Aspheric large reflector without a polishing process, the surface roughness of 5 nm Ra, and the form error of $\lambda/2\;(\lambda=632.8 nm)$ for reference curved surface 200 mm has been required. The purpose of this research is to find the optimum machining conditions for cutting reflector using A16061-T651 and apply the SPDTM technique to the manufacturing of ultra precision optical components of Al-alloy aspheric reflector.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.4 no.1
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• pp.43-48
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• 2005

This paper is described about the technique of ultra-precision machining for an aerospace aspheric mirror. The reflection mirror system generates parallel beams inside a thermal vacuum chamber. A 200mm diameter aspheric mirror was fabricated by SPDTM. Aluminum alloy as mirror substrates is known to be easily machined, but not polishable due to its ductility. Aspheric large reflector without a polishing process, the surface roughness of 10nm Ra, and the form error of ${\lambda}/2$ (${\lambda}$=632.8nm) for reference curved surface 200mm has been required. The purpose of this research is to find the optimum machining conditions for cutting reflector using Al6061-T651 and apply the SPDTM technique to the manufacturing of ultra precision optical components of Al-alloy aspheric reflector.