Thermal Emissivity of Nuclear Graphite as a Function of Its Oxidation Degree (1) -Effects of Density, Porosity, and Microstructure-

서승국; Eung-Seon Kim; Se-Hwan Chi; Suk Hwan Kim; Sang-Woo Lee; Jaeseung Roh

Carbon Letters

Abbr : Carbon Lett.
2009, 10(3), pp.225-229
Publisher : Korean Carbon Society
Research Area : Other Natural Sciences General

서승국 ¹, Eung-Seon Kim ², Se-Hwan Chi ³, Suk Hwan Kim ⁴, Sang-Woo Lee ⁵, Jaeseung Roh ⁶

¹금오공과대학교
²Korea Atomic Energy Research Institute (KAERI)
³Korea Atomic Energy Research Institute (KAERI),
⁴Kumoh National Institute of Technology
⁵Kumoh National Institute of Technology
⁶금오공과대학교

ABSTRACT

Thermal emissivity of commercial nuclear graphites (IG-110, PCEA, IG-430 and NBG-18) following changes in oxidation degrees were examined. Specimens were oxidized to 0%, 5%, and 10% in air flow of 5l/min at 600oC using a furnace, and the thermal emissivities were measured using an infrared spectrum analyzer. The measuring temperatures for the thermal emissivity were 100oC, 200oC, 300oC, 400oC and 500oC. Also density and porosity of the specimens were observed to compare with thermal emissivity. Results showed that emissivity increased with oxidation, and the 10% oxidized NBG-18 showed the highest emissivity (0.890) which value is larger for 24% than the value of as-received specimen. Investigation of factors affecting the emissivity revealed that increases in the surface roughness and porosity due to oxidation were responsible for the increase in emissivity after oxidation.
KEYWORDS

Nuclear graphite, Oxidation, Emissivity, Microstructure, Porosity, Density
REFERENCES (14)

[journal] Mitchell, B. C / 2003 / / J. Nuclear Materials 322(126)

[journal] Luo, X / 2004 / / Nuclear Engineering and Design 227(237)

[journal] Rainer, M / 2004 / / Nuclear Engineering and Design 227(281)

[journal] Kurumada, A / 1997 / / Carbon 35(8) : 1157~

[book] Idaho National Engineering / 2002 / Very High Temperature Gas Cooled Reactor Systems / 2002 Winter ANS Meeting

[journal] Chunhe, T / 1995 / / J. Nuclear Materials 224(103)

[journal] Zhao, C. Y / 2004 / / International Journal of Heat and Mass Transfer 47(2927)

[journal] Zueco, J / 2006 / / Quantitative Spectroscopy & Radiative Transfer 101(73)

[journal] Ball, M / 2008 / / J. of Volcanology and Geothermal Research 173(148)

[journal] Gardner, L / 2006 / / Fire Safety Journal 41(185)

[journal] Yi, J / 2007 / / Applied Surface Science 253(4361)

[journal] Bellayer, S / 2007 / / Carbon 45(2417)

[book] Kim, E. S / 2007 / Effect of a Thermal Oxidation on the Compressive Strengths of Selected Nuclear Graphites / Transactions of the Korean Nuclear Society Autumn Meeting PyeongChang

[journal] Chi, S. H / 2008 / / J. Nuclear Materials 381(9)
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