• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.4
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• pp.40-45
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• 2003

In this paper, to choose the optimum CBN wheel for Internal Grinding at LM Guide, among 7 types of CBN-wheels, the 2 types of CBN-wheels, which were the macrofracture CBN wheel and the microfracture CBN wheel, have been used, and the SCM420H have been used as the workpiece. The working conditions in the grinding experiments were depth-of-cut, table speed, and spindle speed for 4 types of the CBN grinding wheels, 2 types of the lubrications. By the experiments, the loading effect of the microfracture types of the CBN-wheel needed a short dressing interval and resulted in grinding wheel wear and bad surface roughness. However, a macrofracture type of CBN-wheel with the concentration of 100, CB120Q100V showed the best surface roughness quality at a low table speed for internal grinding at LM-guide.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.1
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• pp.3-8
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• 2008

This paper reports some experimental results of cylindrical external grinding using CBN wheels. Many experimental studies for surface grinding have been done, but not for the cylindrical grinding due to the difficulty of grinding force measurement. In this paper a new experimental device has been proposed for the grinding force measurement in cylindrical grinding. The cylindrical grinding experiments were carried out at various grinding conditions with several CBN grinding wheels. The experimental results indicate that the CBN wheels with smaller grains result in the higher grinding forces in both SCM415 and STD11 workpieces. The grinding forces of all wheels were proportional to the infeed speeds and the difference of each wheels was prominent at high infeed speed for SCM415.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.11 no.3
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• pp.98-103
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• 2012

One of the problems in the grinding process using the machining center(MC) with a small diametric wheels is machining error due to decrease of the quill diameter. In this thesis, side-cut grinding is performed with a vitrified bonded CBN wheel on the machining center to establish the basis of the grinding using MC. The grinding force and machining error are investigated experimentally for the change of the machining condition. It is possible to estimate the machining performance by the ratio of the setting depth of cut and actual depth of cut. In addition, the relation between normal grinding force and machining error is presented by the experimental formula.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.2
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• pp.5-13
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• 2003

In this study, experiments of high speed grinding had been earned out in a STD11 specimen for evaluating the grindability with designed CBN grinding wheels Ground surfaces were analyzed and evaluated by means of surface Integrities and wheel damages. The surface roughness and 3 dimensional profile had been used for analyzing the micro-surface integrity. The residual stress of the ground surface had been measured by the x-ray diffraction method. Also, the surface state of the ground specimens and the grinding wheels were evaluated by a metallurgical microscope and SEM system after high speed grinding in order to choose the suitable machining conditions.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.2 no.4
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• pp.25-32
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• 2003

In this study, the grinding characteristics of CBN wheels, such as grinding force and surface roughness, have been compared and analyzed from various working conditions of spindle speed and depth of cut. To actualize high efficient grinding at ceramic and silicon nitride material, electrolytic in-process dressing (ELID) method has been applied at metal bonded diamond and CBN wheels. Super precision grinding using ductile mode at difficult-ta-cut materials could be performed.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.1 no.1
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• pp.55-62
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• 2002

This investigation reports the grinding characteristics of titanium alloy(Ti-6AI-4V). Grinding experiments were performed at various grinding conditions. The grinding forces were measured to investigate the grindability of titanium alloy with the five different wheels including Green carbide, Alumina, Resin Diamond, Resin CBN and Vitrified CBN. To investigate the grinding characteristics of titanium alloy grinding force, force ratio, specific grinding energy and grinding-ratio were measured. Surface roughness was also measured with tracer and the ground surfaces were observed with SEM Residual stress measurement was conducted on the X-Ray Diffractometer. Force ratio of grinding of titanium alloy was very lower than that of grinding of SKD-11 Surface roughness with Resin Diamond wheel was a little larger and rougher surface than that with other wheels Grinding ratio of titanium alloy was a little lower than that of other materials. Grinding ratio of titanium alloy with Diamond wheel was almost six times larger than that With CBN wheel. As a result of five different wheels, the most excellent wheel in grinding of Titanium alloy was Resin Diamond wheel.

• Korean Journal of Materials Research
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• v.5 no.4
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• pp.490-500
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• 1995

다이아몬드와는 달리 CBN은 철족 재료 연삭시 화학적 마모가 거의 없다. 이러한 장점으로 인해 CBN휠이 철강 재료 연삭에 널리 사용되고 잇는 것이다. 그러나 CBN 휠의 성능은 CBN을 붙잡고 있는 결합제에 크게 의존한다. 오늘날 널리 사용되는 결합제인 주석 청동 합금은 내마모성에 한계가 있다. 주석 청동 합금의 내마모성을 증대시키기 위해 Co를 첨가하였다. 이러한 기지합금에 젖음성을 향사시키기위해 Co코팅 CBN을 사용하였다. 기지합금에 20%co를 첨가한 것이 입계에서 연속적인 $\delta$상생성, 취성 증가에 따라 자생작용이 활발하였다. 가장 높은 연삭비를 나타낸 것은 Cu-15wt%Sn, cu-33wt%Sn, co를 40:40:20으로 제작한 휠이었다.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.55-63
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• 2003

In this study, an experimental research of grinding characteristics using super-abrasives for surface carburized and heat treated SCM415 materials, which were usually used to make a linear motion guide block and were comparatively hard-to-machine materials, was carried out. In order to conduct a high efficiency and a accuracy grinding of such materials, grinding processes using CBN (Cubic boron nitride) and 38P grinding wheels have been attempted on a surface grinding machine. The grindability according to each grinding conditions was evaluated by means of a grinding force, a surface roughness and a residual stress. The experimental methods and results were presented in this paper. And also, from a proposed truing method the CBN wheels that combined a copper and a break truer gave a full scope to the wheel's performance.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.12
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• pp.54-59
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• 1999

High precision internal plunge grinding is difficult because of the decrease in the quill stiffness due to the small diameter of wheel. In this paper, the characteristics of internal plunge grinding were investigated. Grinding experiments were performed at various grinding conditions with vitrified bonded CBN wheels. The grinding period was assumed to be consisted of rough grinding and fine grinding. The classification of grinding was determined int terms of the normal grinding forces and actual depth of cut. The experimental results indicate that the higher depth of cut and infeed speed result in the longer rough grinding time. The maximum normal grinding force was nearly equal to the static force and it decreases exponentially as the grinding continues.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.5
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• pp.36-41
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• 2013

One of the problems in grinding process using a machining center(MC) with a small diametric wheels is machining error due to decrease of the quill diameter. In this study, side-cut grinding is performed with a vitrified bonded CBN wheel on the machining center. Grinding experiments are performed at various grinding conditions including quill length, quill diameter and depth of cut. The effect on the grinding force, machining error and surface roughness due to the change of the quill rigidity are investigated experimentally. The slenderness ratio of the quill is significant factor to analyse the change of the grinding force and machining error.