• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.19-25
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• 2001

In metal cutting, chatter is an unstable cutting phenomenon which is due to the interaction of the dynamics of the chip removal process and the structural dynamics of machine tool. When chatter occurs, it reduces tool life and results in poor surface roughness and low productivity of the machining process. In this study, the experiments have been conducted to investigate phenomenon of the chatter in CNC lathe without cutting fluid. In the experiments, two accelerometers were attached at the tail stock and tool holder and the signals were caught. In order to observe the effect of chatter on the surface roughness profiles, surface roughness profiles were generated under the ideal condition and the occurrence of the chatter based on the surface simulation model using surface-shaping system. Finally, the result of experiment and simulation have been compared.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.4
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• pp.19-27
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• 1995

Face milling is required to study cutting process with a view of multipoint cutter. This experimental study mainly deals with the single and multi-insert cutting characteristics using coated tool. Because metal cutting of the single and multi-insert has a large relation to the improvement of productivity, the economic cutting process can be achieved by the analysis of proper metal cutting mechanism. Therefore, machining characteristics of face molling in this paper has been studied by investigating the role of different insert number which is concerned with mean cutting force, the RMS values of AE(acoustic emission) signal, tool life and surface roughness in milling SS 41 and SUS 304. The cutting force and AE signal are monitored to make an analysis of cutting process. The surface roughness of the specimens machined by inserts of different numbers is measured at different speeds, feeds and depth of cut. The width of flank wear is also observed.

• Journal of the Korean Society for Precision Engineering
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• v.25 no.2
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• pp.28-34
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• 2008

Recently, with the development of high speed machining technology for difficult-cutting materials, to improve the cutting performance of cutting tool, fine surface finish of complex shape tools using magnetic polishing technology is in high demand. This study is, therefore, discussed and compared the cutting characteristics of polished tools by the adopted various magnetic polishing moving types a point of view the cutting forces and the tool life. Moreover, the practicality of magnetic polished tools in the wide range cutting conditions is investigated. From obtained results, It is confirmed that the CW(clockwise) revolution and oscillation type as the polishing moving type is proper and magnetic polished tool shows the excellence in high cutting speed range.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.10a
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• pp.19-24
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• 2003

Recently, various efforts to make more speedy and precision machine tool to improve productivity and also various efforts to solve environmental problem are going on, so that dry cutting in manufacturing industry, which needs environmental conscious design and development of manufacturing technique, is becoming a very important assignment to solve. Because dry cutting does not use cutting fluid, we need other methods that can be used instead of cutting fluid, which does cooling, lubricating, chip washing, and anti-corrosion. Especially, because turning is a continuous work, the consideration of tool life and surface roughness due to continuous heat and poor lubrication is important. The purposes of this paper are the consideration of how well the compressed air can work instead of cutting fluid, and also the development of the method to select the optimum machining condition by the minimum numbers of experiments through the Taguchi method.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.6
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• pp.84-91
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• 2003

In metal cutting operation, it is very important that predict cutting force and work surface. Vibration is an unstable cutting phenomenon which is due to the interaction of the dynamics of the chip removal process and the structural dynamics of machine tool. When vibration on, it reduces tool life, results in poor surface roughness and low productivity of the machining process. In this study, the experiments were conducted in machining center without cutting fluid to investigate the phenomenon of vibration. In the experiments, accelerometers were set up at the tail stock and tool holder and signals were picked up. Surface roughness profiles are generated under the ideal condition and the occurrence of vibration based on the surface shaping simulation model.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.184-189
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• 2003

In metal cutting operation, it is very important that predict cutting force and work surface. Vibration is an unstable cutting phenomenon which is due to the interaction of the dynamics of the chip removal process and the structural dynamics of machine tool. when Vibration occurs, it reduces tool life, results in poor surface roughness and low productivity of the machining process. In this study, the experiments were conducted in machining center without cutting fluid to investigated phenomenon of the Vibration. In the experiments, accelerometers were set up at the tail stock and tool holder and the signals were picked up. In this paper, surface roughness profiles will be generated under the ideal condition and the occurrence of the vibration based on the surface shaping simulation model.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2003.04a
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• pp.488-493
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• 2003

This paper presents new skill in tube-mill processing getting the increase in production efficiency and quality in response to the recent request of high grade pipe. In this study, researchers developed the method to improve the precision of pipe and tool life in tube-mill processing. Optimum tool shape is devised by analyzing various simulation and mechanism in cutting process. In order to verify the confidence of the proposed machining technology, it is applied to the real processing machinery in the field.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.10 no.2
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• pp.10-17
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• 2001

Drilling is one of the most important operations performed in the machining industry. And the material of the workpiece has a profound effect on the tool life, the surface finish produced and the overall economy of the process. Hot-rolled high strength steels have been used for automobile structural material, owing to high hardness and machinability of the material. However, in the drilling of hot-rolled high strength steels, the current knowledge of tool wear and machinability are insuf-ficient. There, it is desirable to monitor drill wear status and hole quality changes during the hole drilling process. Accordingly, this paper deals with the cutting characteristics of the hot-rolled high strength steels using common HSS drill. The performance variables include the drilling thrust, torque and drill wear data obtained from drilling experiments con-ducted on the workpiece. Also drill were is measured by acoustic emission system and computer vision system.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.8 no.6
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• pp.71-77
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• 1999

Monitoring of Cutting tool wear is a critical issue in automated machining system and has been extensively studied for many years. An austempered ductile iron(ADI) exhibits the excellent mechanical properties and the wear resistance. ADI has generally the poor machinability due to the characteristic. This paper presents the in-process detection of flank wear of cutting tools using the acoustic emission sensor and the digital oscilloscope. The amplitude level of AE signal(AErms) is mainly affected by cutting speed and it is proportional to cutting speed. There have been the relationship of direct proportion between the amplitude level of AE signals and the flank wear width of cutting tool. The flank wear with corresponding to the tool life is successfully detected with the monitor-ing system used in this study.

• The KIPS Transactions:PartA
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• v.8A no.2
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• pp.75-80
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• 2001

The rapid design of the embedded system is crucial for improving the product’s competitiveness. Existing statechart tools used for designing the embedded system rely on the copy and paste of the statechart for reuse. However, such method has a major drawback of wasting both time and cost of the system developer. This paper implements the component supporting tool. A tool that makes efficient reuse of a statechart by adding a component function to the existing functions is implemented in this paper. Also, to add a component function, this paper restructured the contract as protocol of the inter-component. The implemented tool helps not only reduce the life cycle of a product, but also enhance a product’s competitiveness by supporting the product’s time-to-market.