• Korean Journal of Materials Research
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• v.25 no.6
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• pp.305-316
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• 2015

The study of grinding behavior characteristics on the metal powders has recently gained scientific interest due to their useful applications to enhance advanced nano materials and components. This could significantly improve the property of new mechatronics integrated materials and components. So, a new evaluation method for standardizing grinding equipment and a comparative study for the grinding experiment during the grinding process with various grinding mills were investigated. The series of grinding experiments were carried out by a traditional ball mill, stirred ball mill, and planetary ball mill with various experimental conditions. The relationship between the standardization of equipment and experimental results showed very significant conclusions. Furthermore, the comparative study on the grinding experiment, which investigated changes in particle size, particle morphology, and crystal structure of materials with changes in experimental conditions for grinding equipment, found that the value of particle size distribution is related to the various experimental conditions as a revolution speed of grinding mill and media size.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.10
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• pp.26-33
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• 2004

Ultra precision grinding technology has been developed from the refinement of the abrasive, the development of high stiffness equipment and grinding skill. The conventional wafering process which consists of lapping, etching, 1 st, 2nd and 3rd polishing has been changed to the new process which consists of precision surface grinding, final polishing and post cleaning. Especially, the ultra precision grinding of wafer improves the flatness of wafer and the efficiency of production. Furthermore, it has been not only used in bare wafer grinding, but also applied to wafer back grinding and SOI wafer grinding. This paper focuses on the flatness of the ground wafer. Generally, the ground wafer has concave pronto because of the difference of wheel path density, grinding temperature and elastic deformation of the equipment. Wafer tilting is applied to avoid non-uniform material removal. Through the geometric analysis of wafer grinding process, the profile of the ground wafer is predicted by the development of profile simulator.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.5 no.1
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• pp.33-38
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• 2006

Silicon has been widely used in electronic parts as a semiconductor equipment. It, however, requires much effort to grind without microcrack and chipping because of its high hardness and brittleness. So far, many studies for the grinding of engineering ceramics have been done, but not for the grinding of silicon. In this paper, a theoretical analysis on the grinding forces is introduced. Grinding experiments were performed at various grinding conditions including grinding directions (Up grinding and Down grinding), table speeds and depth of cuts. The grinding forces were measured to compare at various grinding conditions. The experimental values agree well with theoretical ones.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.11 no.5
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• pp.58-64
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• 2002

Mirror surface finish of Si-wafers has been achieved by rotary in-feed machining with cup-type wheels in ELID grinding. But the diameter of the workpiece is limited with the diameter of the grinding wheel in the in-feed machining method. In this study, some finding experiments by the rotary surface grinding machine with straight type wheels were conducted, by which the possible grinding area of the workpiece is independent of the diameter of the wheels. For the purpose of investigating the grinding characteristics of large scale diametrical silicon wafer, grinding conditions such as rotation speed of grinding wheels and revolution of workpieces are varied, and grinding machine used in this experiment is rotary type surface grinding m/c equipment with an ELID unit. The surface ground using the SD8000 wheels showed that mirror like surface roughness can be attained near 2~6 nm in Ra.

• Proceedings of the KSME Conference
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• 2003.04a
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• pp.974-979
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• 2003

As recently optical communication industry is developed, request of optical communication part is increased. Ferrule is very important part which determines transmission efficiency and quality of information in the optical communication part. Most of ferrule processes are grinding which request high processing precision. Particularly, concentricity and cylindricity of inner and outer diameter is very important. The co-axle grinding process of ferrule is to make its concentricity all of uniform before centerless grinding. Surface integrity of ferrule is affected by kind of grinding wheels, grinding conditions, and characteristic of workpiece and equipment. In this study, surface integrity of workpiece according to change of grinding wheel speed, feed rate, regulating wheel speed and grinding force is investigate to improve the concentricity and roundness of ferrule from many experiments.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.309-314
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• 2001

The balance of high speed spindle system with high precision rotation like grinding machine is very important. Traditionally, we use trial and error method to balance the spindle. It takes much time. So we are developing the automatic balancing equipment being used in the grinding machine. The balancing head we develop is wireless. It will be used high-speed grinding machine. We use influence coefficient method to control the automatic balancer. Experiments are based on automatic and manual balancing. We perform test of the vibration filter. It helps to remove noise. The filter and experiments with automatic balancing controller show that automatic balancing control can be successfully achieved with the quick response and good stability characteristics.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.700-705
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• 2003

In this paper, an extended process model is proposed for the application of flexible belt grinding equipment as utilized in robotic grinding. The analytical and experimental results corresponding to grinding force, material removal rate (MRR) and contact area in the robotic grinding shows the difference between the conventional grinding and the flexible robotic grinding. The process model representing the relationship between the material removal and the normal force acting at the contact area has been applied to robotic programming and control. The application of the developed model in blade grinding demonstrates the effectiveness of proposed process model.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.2
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• pp.172-179
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• 2005

A high-precision centerless grinding machine has been recognized as a core equipment performing the finish outer-diameter grinding process of ferrules which are widely used as fiber optic connectors. In this study, in order to realize the high-precision centerless grinding machine, the structural characteristic analysis and evaluation are carried out on the virtual prototype consisted of the steel bed, hydrostatic GW and RW spindle systems, hydrostatic RW feed mechanism, RW swivel mechanism, and on-machine GW and RW dressers. The loop stiffnesses of centerless grinding machine are estimated based on the relative deformations between GW and RW caused by the grinding forces. And the simulated results illustrate that the concrete-filled bed has the considerable effect on the improvement of the structural stiffness of centerless grinding machine.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.53-56
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• 1995

Electrolytic In-Process Dressing grinding technique which enables application of metal bond wheels with fine superabrasives in mirror surface grinding operations has developed. This paper provides charateristic evaluation of power supply supply that we developed and general charateristics of ELID grinding. The electric behaviors are compared each about two different electrode which has 1/4, 1/6 the area of entire wheel surface, and two different fluids which has 1:50, 1:30 the quantity of water was used to dillute grinding fluids. The results show that ELID grinding method is useful for mirror surface machining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.19-22
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• 2005

As the optical communication industry is developed, the demand of optical communication part is increasing. $ZrO_2$ ceramic ferrule is very important part which can determines the transmission efficiency and information quality to connect the optical fibers. In general $ZrO_2$ ceramic ferrule is manufactured by grinding process because the demands precision is very high. And the co-axle grinding process of $ZrO_2$ ceramic ferrule is to make its concentricity all of uniform before centerless grinding. When co-axle grinding of ferrule supported by two pin, pin chucking alignment accuracy is very important. This paper deals with the analysis of the chucking alignment experiment with parallel error on the micro feeding equipment. Thus, if possible be finding highly good the chucking alignment of two pin.