• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.10
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• pp.1499-1505
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• 2010

In general, magnetic abrasive polishing can be used to effectively produce a mirror-like surface; however, industrial applications of this process involve some unsolved problems. For example, the polishing efficiency is low, and the used abrasives have to be treated. In this study, which is aimed at solving these problems, a novel medium of silicone gel, consisting of ferromagnetic particles and abrasives, is developed, and the effect of this medium is assessed on the basis of Taguchi's experimental method. The workpiece is a tungsten carbide steel and the surface roughness after magnetic abrasive polishing using the silicone gel is evaluated.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.3
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• pp.313-318
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• 2013

Magnetic abrasive polishing is an advanced deburring process for nonmagnetic materials and micropattern products that have non-machinability characteristics. Despite these advantages, there are some problems with using MAP for deburring. MAP has introduced geometric errors into microgrooves because of an over-cutting force caused by uncontrolled magnetic abrasives in the MAP tool. Thus, in this study, to solve this problem, an EP (electrolyte polishing)-MAP hybrid polishing process was developed for deburring microgrooves in an STS316 material. In addition, an evaluation of EP-MAP for the deburring of microgrooves was carried out by profiling the burrs. The results of the experiment showed geometric errors after the deburring process using MAP. However, in the case of EP-MAP, no geometric error was observed after the process because of the lower material removal rate in EP-MAP.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.9 s.174
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• pp.7-13
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• 2005

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.1832-1835
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• 2003

This paper suggests the selective ultra precision polishing techniques for micro die and mold parts using magnetic-assisted machining. Fabrication of magnetic abrasive particle and their polishing performance are key technology at ultra precision polishing process of micro parts. Conventional magnetic abrasives have disadvantages. which are missing of abrasive particle and inequality between magnetic particle and abrasive particle. So, bonded magnetic abrasive particles are fabricated by several method. For example, plasma melting and direct bonding. Ferrite and carbonyl iron powder are used as magnetic particle where silicon carbide and Al$_2$O$_3$ are abrasive particle. Developed particles are analyzed using measurement device such as SEM. Possibility of magnetic abrasive and polishing performance of this magnetic abrasive particles also have been investigated. After polishing, surface roughness of workpiece is reduced from 2.927 $\mu\textrm{m}$ Rmax to 0.453 $\mu\textrm{m}$ Rmax.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.4
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• pp.435-441
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• 2017

Studies on self-healing have currently been diversified and the methods to evaluate the studies have become more diversified as well. Among them, the back-scattered electron (BSE) image acquired through the scanning electron microscope (SEM) is attempted as the means to evaluate the self-healing effect on cracks. In order evaluate by the BSE image, sophisticated pre-processing of specimen is critical and this injected inside the particle, pore and artificial crack of the hardener to stabilize the structure of the newly generated self-healing product and it enables to endure the stress on polishing without deformation. The impregnated specimen smoothen the surface to obtain the BSE image of high resolution that polishing is made for diamond suspension for wet polishing after dry polishing. As a result of evaluating the self-healing product on the impregnated and polished self-healing specimen, the generated product is formed from the surface of the artificial crack and the self-healing substances are confirmed as $Ca(OH)_2$ and C-S-H.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.43-47
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• 1995

The ball screw is one of the important mechanical parts for the linear motion feeding systems. The usage of the ball screw has been growing in various industrial fields such as CNC machine tool, industrial robot and automated systems. Because of ever increasing demand for ball screws, increased accuracy and quality of the ball screw is needed,especially the surface roughness of the ball contact area in order to diminish noise and vibration. Therefore to improve the surface roughness of the area,we introduced magnetic assisted polishing which is one of the new potential polishing methods. In this study, diamond slurry and iron powder was used for magnetic assisted polishing of the ball bearing surface. This polishing process was experimentally confirmed to improve the surface roughness of the ball bearing.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.11
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• pp.1643-1648
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• 2010

It is very difficult to polish non-magnetic materials by the magnetic abrasive polishing (MAP) process because magnetic force is required for MAP, but the magnetic force for non.magnetic materials is low. In this study, we aimed to develop a magnetic array table and control the magnetic polarity such that the magnetic force can be increased for the MAP of non-magnetic materials. The newly designed magnetic array table has 32 electro magnets, and the magnetic polarity of each electro-magnet can be easily controlled by changing the electric polarity. It was analytically verified that the magnetic flux density of non-magnetic materials can be varied by varying the applied magnetic polarity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.85-85
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• 2003

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.241-244
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• 2002

Deburring is conducted using MAF(magnetic abrasive finishing) method. Magnetic inductor is designed and manufactured to generate proper magnetic induction far deburring the burr formed in drilling SM45C. Rotational speed, table feed rate, grain size of powder and working gap are changed to investigate the effect on deburring.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.151-157
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• 2004

In this paper deals with behavior of the magnetic abrasive using sludge on polishing characteristics in a new internal finishing of seamless stainless steel tube applying magnetic abrasive polishing. The magnetic abrasive using sludge-abrasive grain WA and GC used to resin bond fabricated low temperature. And sludge of magnetic abrasive powder fabricated that sludge was crused into 200 mesh. The previous research have made an experiment in the static state the movement of magnetic abrasive grain is nevertheless in the dynamic state. In this paper, We could have investigated into the changes of the movement of magnetic abrasive grain. In reference to this result, we could have made the experiment which is set under the condition of the magnetic flux density, polishing velocity according to the form of magnetic brush.