• Journal of the Korean Society for Precision Engineering
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• v.15 no.11
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• pp.189-198
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• 1998

Recently, monitoring of tool life is a matter of common interesting because tool life affects precision, productivity and cost in machining process. Especially flank wear has a direct effect on cutting mechanism, so the various pattern of cutting force is obtained experimentally according to variation of wear condition. By investigating cutting force signal, AR(Autoregressive) modeling and correlation dimension analysis is conducted in turning operation. In this modeling and analysis, we extract features through 6th AR model, correlation integral and normalized correlation integral. After the back-propagation model of the neural network is utilized to monitor tool life according to flank wear. As a result. a very reliable classification of tool life was obtained.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.7
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• pp.99-107
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• 1997

An algorithm is developed to find optimal machining parameters for multiple machining environments. The cutting rate-tool life (R-T) characteristic curve presents the general loci of optima and is useful for the flexible machining operations planning. The R-T characteristic curve for the machining economics prob- lems with linear-logarithmic tool lofe model may be determined by applying sensitivity analysis to log-dual problems. Three cases of the change of machining environments are considered. An end milling example is constructed to illustrate the algorithm.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1996.03a
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• pp.30-35
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• 1996

• Journal of the Korean Society for Precision Engineering
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• v.5 no.2
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• pp.7-14
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• 1988

작업물(Work)을 기계에 장입출, 가공에 필요한 공구류의 공급 등이 완전 자동화 된 기존의 사출성형기 Series를 제조하는 FA Systme은, MAP 대응의 FA System 으로 개량되었다. 이 논문은, MAP 대응 새 FA 시스템의 MAP에서 분산.통괄의 역할을 하도록 개발된 Cell controller의 정보관리기능 가운데 하나의 응용으로서 제조공정을 자동적으로 Scheduling 하는데 Expert 시스템(전문가시스템)을 적용한 idea를 소개하는 것이다. 이 idea의 적용 으로 인하여 제조공정의 scheduling 작염은 종래의 주단위로 부터 일일단위의 작업으로 처리가 가능해졌고, 또, 공구수명관리기능의 부가로 무인운전시의 기계의 가공율도 종래보다도 녹일 수가 있었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.05a
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• pp.779-782
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• 2000

This paper aimes to clarify the effects of tool geometry on the tool life in machining of STS 304. The main conclusions obtained were as follows. The lift of TiN coated cermet tool was the longest, exhibiting shorter life in the order of P2O, cermet, TiCN coated carbide and TiAIN coated carbide tools. S-type tool showed the best performance of all tools used in this tests due to preventing the boundary wear of the side cutting edge.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.6 no.3
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• pp.36-43
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• 1997

In order to make unmanned machining systems with satisfactory performances, it is necessary to incorporate appropriate condition monitoring systems in the machining workstations to provide the required intelligence of the expert. This paper deals with condition monitoring for tool wear and breakage during turning operation. Developing economic sensing and identification methods for turning processes, sound pressure measurement and digital signal processing technique are proposed. The validity of the proposed system is confirmed through the large number of cutting tests.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2015.05a
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• pp.173-173
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• 2015

고온에서 우수한 기계적 물성을 보이는 CrZrSiN 코팅은 공구분야에 적용 가능성이 크지만, 공구의 수명과 밀접한 연관이 있는 밀착력에 대한 연구는 보고된 바가 없다. 본 연구에서는 텅스텐 카바이드(WC) 모재와 CrZrSiN 코팅 사이의 밀착력을 향상시키기 위해 다양한 중간층이 합성되었으며, 중간층의 경도와 탄성계수 비율(H/E ratio)이 코팅의 밀착 특성에 영향을 미치는 것으로 판단되었다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.12 no.5
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• pp.1055-1062
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• 1988

The characteristics of tool wear and the machinability in cutting of GFRP have been studied. The wear behavior of carbide insert tools(P20, M10, K10) and Cermet in TiC grade was studied by turning of changing the cutting condition. Machinability could be estimated as the following empirical formula, CT$^{n}$ =W The main results obtained are as follows: (1) Dependence of rate of tool wear on cutting speed; with increases of cutting speed, the rate of tool wear initially increases gradually(1st range), then it increases proportionally to cutting speed(2nd range), and finally the rate is constant(3rd range). (2) When the contact length has a main, effect on tool wear, the cutting speed does nit affect the tool wear. On the contrary, the cutting speed has a main effect on tool wear, the contact length does not affect the tool wear. (3) The order of machinability is K10, M10, P20 and Cermet in TiC grade.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.2
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• pp.471-477
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• 2012

SCM420 steel tempered after performing gear hove PACVD carbide coating on the surface after the cutting surface hardness was high. Difficult-to-cut, without coating is classified as mild as large, including materials like mild, high strength that improves tool life and productivity have limited availability. Drive to improve it in the TiCN-coated carbide call for war to the finish coating on cutting a hob skiving good workability, tool wear less, 2.5-fold increase in tool life results were obtained. Experiments using CNC Skiving hobbing machine with wet cutting conditions, cutting speed and feed rate to apply a variety of the tool wear and surface roughness data were obtained. Results from condition 2 (V = 200m/min F = 0.7mm/rev) cutting speed feed mark the cutting surface microstructure and surface roughness Rmax $4.7{\mu}m$(Ra $1.19{\mu}m$) of the data was obtained.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.10a
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• pp.51-56
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• 2001

공작기계로 금속을 절삭할 때 공작기계의 불안정, 즉 자려진동의 발생은 절삭과정과 공작기계구조 두 요소의 동적 거동에 기인한다. 공작기계의 채터와 구조의 동적인 거동은 모든 금속가공에서 가공물의 표면조도와 공구수명, 공작기계의 수명에 큰 영향을 미친다. 이와 같은 채터와 동적인 거동을 해석함으로써 최적의 절삭 조건을 결정할 수 있으나, 이러한 연구에서 가장 어려운 점은 기계구조와 절삭과정이 폐회를 구성하고 있기 때문이다.