• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.3
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• pp.118-125
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• 1998

Chip control is a major problem in automatic machining process, especially in finish turning operation. In this case, chip breaker is one of the important factors to be determined. As unbroken chips are grown. these deteriorate the surface roughness. and proces automation can not be carried out. In this study to get rid of chip curling problem while turning internal hole. optimal chip breaker is selected from the experiment. The experiment is planned with Taguchi's method that is based on the orthogonal arrary of design factors. From the response table. cutting speed, feedrate, depth of cut and tool geometry turn to be major factors affecting chip formation. Then, optimal chip breaker is selected. and this is verified as good enough for chip control from the experiment.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.147-152
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• 2002

The mechanism of the aerosol(mist) generation generally consists of spin-off, splash, and evaporation/condensation. Host researchers showed some theoretical model for predicting the particulate size and generation rate without real cutting in turning operation. These models were based on the spin-off mechanism, and verified good for modeling the process. However, in real machining, the cutting tool destroys the flow direction of the cutting fluid and generate the heat by the relative motion of between tool and workpicee, and so the mass loading of the mist is greatly increased as compared with non-cutting. In this paper, we show some experimental data that the mist formation characteristics of cutting is different from that of non-cutting.

• Journal of the Korean Society of Industry Convergence
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• v.4 no.2
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• pp.127-132
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• 2001

In turning, the chip may be produced in the form of continuous chip or discontinuous chip. The continuous chips are dangerous to the operator and difficult to be handled at high speed machining. The signal of AE(Acoustic Emission) is found out to be related to cutting conditions, tool materials, test conditions and tool geometry in turning. In this study, the relationship between AE signal and chip form was experimentally investigated. The experimental results show that the types of chip form are possible to be classified from the AE signal using fuzzy logic.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.8
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• pp.21-28
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• 1997

This paper presents the influence of the process parameters on the change in dynamic behavior of a lathe turning system. With variation of feed rate, depth of cut, direction of tool motion, cutting speed and tool location along the workpiece, the dynamic characteristics of stable cutting, chatter transition and fully developed chatter regions are demonstrated. The workpiece vibration during machining is continuously measured at different tool locations along the workpiece and quantitatively analyzed. Complex linear behavior due to change of process parameter values as well as fundamental wystem nonlinearity due to change of process configuration indicated by a tool path dependence of the locations of chatter onset and disappearance are described. Finally, the structural characteristics of the turning system which can have large and nonlinear effects on system behavior are presented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.215-216
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• 2007

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2012.05a
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• pp.89-90
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• 2012

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.10a
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• pp.273-274
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.103-104
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• 2010

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.15 no.1
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• pp.20-25
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• 2016

Recently, the requirements for high precision and efficiency machining are gradually increased to raise international competitiveness at the industrial fields of automotive and gears. This trend had made effects on the industrial fields in Korea and which needs further studying of high accuracy and efficiency machining. This study is to investigate the effects of Jig type chuck for roundness improvement in CNC turning machining of high stage speed gear. After hobbing machining, Dimensional change before and after heat treatment was very largely generated. In order to solve this problem was to develop a jig type chuck. After the heat treatment, the operation of the chuck which was the most distinguished equipment among Jig type chuck(0.006mm), Scroll type chuck(0.05mm) and Bolt type chuck(0.04mm). Therefore, Jig type chuck was satisfied the requirement from the actual field(0.02mm).

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.1
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• pp.57-62
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• 2003

Machining technique for optical crystals with single point diamond turning tool is reported in tills paper. The main factors influencing the machined surface quality are discovered and regularities of machining process are drawn. Optical crystals have found more and more important applications in the field of modern optics. Optical crystals are mostly brittle materials of poor machinability The traditional machining method is polishing which has many shortcomings such as low production efficiency, poor ability to be automatically controlled and edge effect of the workpiece. SPDT has been widely used in manufacturing optical reflectors of non-ferrous metals such as aluminum and copper which are easy to be machined for their proper ductility. But optical crystals being discussed here are characterized by their high brittleness which makes it difficult to obtain high quality optical surfaces on them. The purpose of our research is to find the optimum machining conditions for ductile cutting of optical crystals and apply the SPDT technique to the manufacturing of ultra precision optical components of brittle materials. As a result, the cutting force is steady, the cutting force range is 0.05-0.08N. The surface roughness is good when spindle is above 1400rpm, and feed rate is small. The influence of depth of cut is very small.