Premium
Oxidation of Silicon Carbide in Environments Containing Potassium Salt Vapor
Author(s) -
Pareek Vinod,
Shores David A.
Publication year - 1991
Publication title -
journal of the american ceramic society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.9
H-Index - 196
eISSN - 1551-2916
pISSN - 0002-7820
DOI - 10.1111/j.1151-2916.1991.tb04059.x
Subject(s) - oxidizing agent , potassium , thermogravimetric analysis , salt (chemistry) , alkali metal , water vapor , silicon carbide , chemical engineering , chemistry , inorganic chemistry , silicon , kinetics , carbide , materials science , mineralogy , metallurgy , organic chemistry , physics , quantum mechanics , engineering
At high temperatures in clean oxidizing environments, SiC forms a very protective SiO 2 film, but, in environments containing low levels of gaseous alkali salt contaminants or where condensed salts may deposit on the surface, the resistance of the film is significantly reduced. Oxidation kinetics of SiC were measured by continuous thermogravimetric analysis in a controlled environment containing CO 2 , H 2 O, and O 2 plus low levels of potassium‐containing salts. Potassium was found to be incorporated into the SiO 2 scale and to significantly change its transport properties and its morphology. The rate of scale formation was found to increase directly in proportion to K in the scale. A change in mechanism was observed when water vapor was added to the reacting gas stream.