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Kim, J.S.;Kim, J.S.;Kang, E.G.;Lee, S.W.;Park, H.W.
- Journal of the Korean Society of Manufacturing Technology Engineers
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- v.22 no.6
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- pp.931-936
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- 2013
Recently, the use of large-electron-beam polishing for polishing complex metal surfaces has been proposed. In this study, the temperature induced by a large electron beam was predicted using the heat transfer theory. A finite element (FE) model of a continuous wave (CW) electron beam was constructed assuming Gaussian distribution. The temperature distribution and melting depth of an SUS304 sample were predicted by changing electron-beam polishing process parameters such as energy density and beam velocity. The results obtained using the developed FE model were compared with experimental results for verifying the melting depth prediction capability of the developed FE model.
https://doi.org/10.7735/ksmte.2013.22.6.931 인용 PDF KSCI

Lim, Sun Jong
- Laser Solutions
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- v.18 no.3
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- pp.6-8
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- 2015
Finishing process includes deburring, polishing and edge radiusing. It improves the surface profile of specimen and eliminates the alien substance on surface. Deburring is the elimination process for debris of edges. Polishing lubricates surfaces by rubbing or chemical treatment. There are two types for electron finishing. The one is using pulse beam. The other is using the convergent and scanning electron beam. Pulse type device appropriates the large area process. But it does not control the beam dosage. Scanning type device has advantages for dosage control and edge deburring. We design the convergence and scan type. It has magnetic lenses for convergence and scan device for scanning beam. Magnetic lenses consist of convergent and objective lens. The lenses are designed by the specification(beam size and working distance). In this paper, we evaluate the convergence performance by pattern process. Also, we analysis the results and important factors for process. The important factors for process are beam size, pressure, stage speed and vacuum. These results will be utilized into systematizing pattern shape and the factors.
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Kim, Dong-Ik;Kim, Byung-Kyu;Kim, Ju-Heon
- Applied Microscopy
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- v.45 no.4
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- pp.218-224
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- 2015
A technical overview on the various sample preparation methods for electron backscattered diffraction (EBSD) analysis is carried out. The mechanical polishing with colloidal silica finish, electro-chemical polishing, dual layer coating and ion beam milling are introduced for the common sample preparation methods for EBSD observation and some issues that are frequently neglected by the common EBSD users but should be considered to get a reliable EBSD data are discussed. This overview would be especially helpful to the people who know what EBSD technique is but do not get a reliable EBSD data because of difficulties in sample preparation.
https://doi.org/10.9729/AM.2015.45.4.218 인용 PDF KSCI

Kim, Hyun-Jeong;Jung, Sung-Taek;Lee, Joo-Hyung;Baek, Seung-Yub
- Design & Manufacturing
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- v.14 no.1
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- pp.56-62
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- 2020
An electron beam was used to mainly utilize for polishing, finishing, welding, a lithography process, etc. Due to the high technical level of difficulty of high-power density electron beam, it is difficult to secure related technologies. In this study, research was carried out to improve the machinability by developing the vaporized amplification sheets to realize the electron beam drilling technology. Their vaporized amplification sheets were analyzed by using the measurement of chemical and composition, which is such as TGA, SEM. We analyzed micro-hole processing using a microscope. Also, the thermal characteristics of vaporized amplification sheets are highly significant for applying to high-power density electron beam technique. So, we finished the vaporized amplification sheets according to the process conditions and analyzed it according to the machining conditions of the electron beam. It was confirmed that the effect on the experimental results differs depending on the influence of the metal powder contained in the developed material.
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