• Journal of the Korean institute of surface engineering
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• v.41 no.1
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• pp.38-42
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• 2008

316L stainless steel welding tube was electrolytically polished and the inner surface characteristics of the tube were tested. Electro-polishing variables such as current, voltage, concentration of electrolyte and electropolishing time were changed to seek for optimum condition. These makes a optimum conditions for the electro-polishing as 4000 A, 9 V, 1.7 specific gravity of electrolyte, and 30 minute of electro-polishing time. It makes the surface roughness as Ra < $0.25{\mu}m$. XPS test resulted as the ratio of CrO/FeO equals or more to 3/1. AES test resulted as the thickness of CrO film of $38{\AA}$. DTA test resulted as the tube did not react with $N_2,\;H_2\;and\;O_2$ gas below 1073K. As summarize above results, the electro- polished 316L stainless steel welding tube satisfied the conditions to apply as a pipeline for semi- conductor production facility and clean room.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.13 no.5
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• pp.76-81
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• 2014

The Engineering ceramics have some excellent properties as materials for modern mechanical and electrical components. It is, however, not easy to polish them efficiently because they are strong and hard. This study is carried out to obtain a mirror surface on engineering ceramics by surperfinishing with high efficiency. To achieve this, we conducted a series of polishing experiments using representative engineering ceramics, such as $Al_2O_3$, SiC, $Si_3N_4$ and $ZrO_2$, using diamond abrasive film from the perspective of oscillations peed, the rotational speed of the workpiece, contact roller hardness, contact pressure and feed rate. Furthermore, the polishing efficiency and characteristics for engineering ceramics are discussed on the basis of optimal polishing time and surface roughness. Our results confirmed that efficient superfinishing conditions and polishing characteristics of engineering ceramics can be determined.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.5
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• pp.795-799
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• 2013

This paper describes a novel hybrid surface polishing process combining non-traditional electrochemical polishing (ECP) with external artificial ultrasonic vibration. The purpose of this study is to develop an easier method for improving stainless steel surfaces. To this end, vibration electrochemical polishing (VECP), a novel ultrasonic manufacturing process, for enhancing electrochemical reaction and surface quality compared with that achieved using conventional ECP is suggested. In addition, for finding the optimized experimental conditions, the two methods are compared under various current densities. Localized roughness of the work material is measured with atomic force microscopy (AFM) and scanning electron microscopy (SEM) for obtaining detailed surface information.

• 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 Precision Engineering Conference
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• 2003.06a
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• pp.561-564
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• 2003

The machining technology for the removal of micro-burr has been demanded because electrode parts of electron gun have minute holes. In this study, Magnetic Assisted Polishing(MAP) is applied to remove the micro-burr instead of the contentional polishing process such as the etching and barrel. Optimal polishing conditions are selected from many experiments using the tool of the flat end slit type. On the basis of experimental results, the deburring machine for the Magnetic Assisted Polishing of electrode part is developed and its performance is evaluated.

• Tribology and Lubricants
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• v.15 no.1
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• pp.90-97
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• 1999

Chemical-Mechanical Polishing (CMP) refers to a material removal process done by rubbing a work piece against a polishing pad under load in the presence of chemically active, abrasive containing slurry. CU process is a combination of chemical dissolution and mechanical action. The mechanical action of CMP involves tribology. The liquid slurry is trapped between the wafer (work piece) and pad (tooling) forming a lubricating film. For the first step to understand material removal rate of the CMP process, the lubricational analyses were done with commercial 100mm diameter silicon wafers to get nominal clearance of the slurry film, roll and pitch angle at the steady state. For this purpose, we calculate slurry pressure, resultant forces and moments at the steady state in the range of typical industrial polishing conditions.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.8
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• pp.887-892
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• 2014

In a conventional magnetic abrasive polishing process, the polishing abrasives are mixed with ferrous particles and slight cutting oil to form a cluster of abrasives. However, when a tool rotates at a high revolution speed, most of the polishing abrasives are scattered away from it due to the increase in centrifugal force. This phenomenon directly reduces the polishing efficiency. The use of a highly viscous matter such as silicone gel instead of cutting oil for mixing is one method to solve this problem and increase abrasive adhesion. Another method to avoid high abrasive scattering is the application of wet magnetic abrasive polishing (WMAP). In WMAP, abundant mineral oil is preliminarily applied to the workpiece surface. This study experimentally evaluated the effect of WMAP on abrasive adhesion. The relationship between the amount of working abrasives and polishing conditions was characterized. Despite the lower adhesion ratio of polishing abrasives, the surface roughness was found to be significantly improved as the result of WMAP.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.8
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• pp.134-140
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• 2002

Chemical mechanical polishing of aluminum and photoresist using colloidal silica-based slurry was experimented. The effects of slurry pH, silica concentration, and oxidizer ($H_2O_2$) concentration on surface roughness and removal rate were studied. The optimum slurry conditions for reduction of micro-scratch were investigated. The optimum chemical mechanical polishing with the colloidal silica-based slurry was compared with conventional chemical mechanical polishing with alumina-based slurry. Chemical mechanical polishing of the aluminum with the colloidal silica-based slurry showed improved result but chemical mechanical polishing of the photoresist did not. The improved result was comparative with that of chemical mechanical polishing with filtered alumina-based slurry which one of desirable methods to reduce the micro-scratch.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.11a
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• pp.89-90
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.245-246
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• 2010