• Korean Journal of Metals and Materials
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• v.49 no.11
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• pp.831-838
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• 2011

Effects of spangle size and crystallographic characteristics on the surface appearance, galling properties, and adhesive strength of hot-dip galvanized steel sheets have been investigated. Both spangle size and crystallographic orientation measured by optical microscopy, scanning electron microscopy, and X-ray diffraction were identified as critical factors influencing the galvanized coating performance. By decreasing the spangle size, surface appearance and galling properties related to the friction coefficient were significantly improved. However, low temperature adhesive-strength with small spangle galvanized steel sheets showed lower values compared to commercially used galvanized coating. The variation of adhesive strength in terms of spangle size has been clarified.

• Journal of Surface Science and Engineering
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• v.29 no.4
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• pp.253-260
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• 1996

Regular spangle hot dip galvanized steel sheets were made in the zinc bath containing a small amount of Al and with the addition of Pb, Sb, Sb-Mg, Sb-Cu and Bi respectively whose average glosses were measured. Zero-spangle hot dip galvanized steel sheets were also made by spraying a 2% $NH_4H_2PO_4$ solution on molten coating surfaces with exactly the same chemical compositions as above used for regular spangle and whose glosses and corrosion losses were also evaluated. For manufacturing zero- spangle hot dip galvanized steel sheets with high brightness, the zinc bath with 0.02%Sb and the spraying of a 2% $NH_4H_2PO_4$ solution were proposed and for better brightness and corrosion resistance, the zinc bath with 0.02% Sb-0.50%Mg and the spraying of a 2% $NH_4H_2PO_4$ solution were also proposed.

• Journal of Surface Science and Engineering
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• v.32 no.4
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• pp.547-554
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• 1999

The interfacial reaction, spangle and coating thickness of galvanized steel in Ni added Zn-0.18Al bath have been investigated. The size of spangle and thickness of reaction layer were observed under an optical microscope, SEM and EDS. Analysing the experimental results concerning spangle size of galvanized steel it was found that Ni addition in Zn-0.18Al bath tended to be minimized spangle size. For Zn-0.18Al bath, addition of 0.1Ni suppressed the formation of Fe-Zn intermetallic compounds but increased with Ni content above 0.1%. The coating thickness of galvanized steel was reduced with Ni addition in Zn-0.18Al bath, especially in Zn-0.18Al-0.05Ni bath. Addition of Al in Ni containing bath resulted in forming the Al-Ni intermetallic compounds such as $Al_3$Ni$_2$ and $Al_2$Ni which consist most of top precipitates.

• Journal of the Mineralogical Society of Korea
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• v.22 no.4
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• pp.395-405
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• 2009

The maturity of amber matrix and inclusion was studied to explore the effect of heat treatment on the formation of the sun spangle in the transparent Baltic amber from Gdansk, Poland. Optical microscope revealed two types of inclusions in the original amber samples. The inclusions in the amber which had sun spangle were dramatically expanded by the heat treatment, comparing to those without sun spangle which contains fissure and shows different refractive index. The amber sample which didn't show sun spangle after the heat treatment showed a strong carbon related peak in TOF-SIMS spectra and weak oxygen related peak. it means that the maturity of this amber sample is comparatively higher than the one with spangle. The two amber samples show similar IR spectra before the heat treatment. However, the amber which had sun spangle exhibited an additional 1019 $cm^{-1}$ absorption peak and a more intense 887 $cm^{-1}$ peak. The different chemical compositions between the two types of amber is believed to be due to the different absorption spectra between 1000~600 $cm^{-1}$. According to the study of DSC analysis, the two samples show different DSC profiles. Although they have the same geological origin, their geological ages are different and have different chemical compositions. Thus, they exhibited different behavior after the heat treatment. The formation of sun spangle seemed to depend on the difference in the heat expansion rate of amber matrix with different maturity and chemical compositions.

• Corrosion Science and Technology
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• v.10 no.5
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• pp.157-161
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• 2011

HY-Galume is a brand name of 55%Al-Zn coated steel sheets produced by Hyundai HYSCO. Heavy gauged HY-Galume having thickness around 2 millimeters is used as a steel casing for the electrical distribution panel in the construction market. It requires a strict surface quality because it is used indoors. In this paper, several troubleshooting experiences in producing heavy gauged HY-Galume are proposed.

• The Research Journal of the Costume Culture
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• v.8 no.5
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• pp.638-647
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• 2000

The purpose of this study is to discover the interrelationship between modern costumes and Seung-Hee Choi's dancing costumes in 1930s. Seung-Hee Choi, who was a dancing pioneer in Korea, introduced the modern dancing costumes for the first time in Korea. The results are as followed ; First, we can find Eroticism in Choi's dancing dress. Choi's dancing costume had used gold thread, silver thread, spangle, see-through and a half-naked body clothing that decorated with beads and cords. It is similar to modern costumes in ubjet mtter, silhouette, design, and so on. Second, the influence of Futurism was in her dancing costumes, that is, it represented asymmetry designs and rectilineal figures. Third, not only beauty but also a Functionalism was expressed in her dancing costumes. Functional beauty was shown through bias cut, pleats, slit, and so on.

• Journal of ILASS-Korea
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• v.5 no.3
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• pp.45-54
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• 2000

A novel electrostatic splaying method for solidifying a galvanized coating layer was studied. Our experimental results and computer simulations showed that electric field could assist the fine droplets to attach on the steel surface and change the sprayed droplets trajectory especially in the space near the steel surface. It was necessary to apply the electric voltage higher than - 20 kV to obtain the enough electrostatic attraction force between droplets and the steel sheet.

• Journal of the Korea Fashion and Costume Design Association
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• v.2 no.2
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• pp.41-54
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• 2000

History of fashion and clothing is needed to understand modern fashion and to predict Future mode. The period of Romanticism in fine arts was from the end 18th century up to the first half of 19th century. The characteristics of shilouttes were found in the emphasis owomen's body line. This feature of romantic fashion is founded in 1960, 1970, 1980, 1990'mode. Major characters of this times are retro of romantic costume. As time goes by, more romantic fashion was set up and new corncern of 2000 fashion trend. The Characteristics of romantic image in 2000 of fashion trend are the emphasis of romantic details and decorations. Such as ruffle, frill, shirring, beads, spangle, sequin, flower. Trend colors are pink, lilac, aqua blue, yellow, green, pastel color. Trend materials chiffon, organza, satin, velvet, gauze, georgette, lace and glittery material. And floral print and stripe print. Forward­looking fashion is ethnic­romantic image influenced India. Trend and fashion have very close relationship and if it is fully comprehended, it will be good opportunity to awkardness againnst new fashion line.

• Journal of Surface Science and Engineering
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• v.33 no.4
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• pp.233-240
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• 2000

A novel electrostatic spraying method to solidify molten zinc coating layer was studied by SEM and measurement of sample's temperature. The sprayed droplets also served as nucleation sites in the solidification reaction of molten zinc but might leave the pitting mark by impinging on its surface especially at high spray pressure. Our experimental results showed that electric field could change the sprayed particle trajectories and assist the fine droplets to attach on the surface. Thus, by reducing the spray pressure and by applying the electric voltage higher than -20 KV to charge the droplets electrostatically, we could produce the spangle free galvanized coating layer without pitting.

• Journal of Surface Science and Engineering
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• v.33 no.5
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• pp.387-397
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• 2000

Antimony in the galvanizing bath had greater effect on the growth of grains in the solidification of molten coating layer and on the decrease of its surface roughness than lead. Particularly 0.01 wt % antimony in the galvanizing bath showed much stronger effect than expected considering its low surface tension value. These effects were seemingly originated from the development of preferred orientation of (0002) plane parallel to steel surface. Antimony was found to be widely distributed in form of orderly arrangement throughout the coating layer unlike lead from the results of surface analyses on coating layers as received and on those as etched in chromating solution. In addition, supercooling in the 0.07 % antimony and the 0.2 % lead galvanizing bath was also measured to be in the range of$ 2~4^{\circ}C$ and $9~11^{\circ}C$ respectively, and it indicates that antimony forms fine dendrite expanded rapidly on the steel surface.