ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The coating of molten silicate glass on a porous carbon substrate was developed, withoutthe formation of cristobalite at the carbon-glass layer interface, in order to improve the steamoxidation and thermal shock resistance. Initially, suitable conditions for coating were assumed fromthermodynamic analysis. Based on these calculations, the wettability of the carbon to molten glasswas modified by infiltration and pyrolysis of a Si-N precursor, and the coating with glass was carriedout under higher N2 partial pressures. As a result, carbon substrates were completely sealed with glass,without the production of cristobalite at the interface, and the glass was infiltrated into the substrate.In contrast, coating with glass at lower N2 partial pressures, such as in Ar, were followed by theformation of cristobalite along with many pores at the interface. The structural changes occurring as aresult of variation of the N2 partial pressure during sealing with glass are in good agreement with thethermodynamic analysis. The glass-coated carbon materials, which were fabricated at higher N2partial pressure, possessed excellent steam oxidation resistance and thermal shock resistance
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/51/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.317-318.343.pdf
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