TY - JOUR
T1 - Characterization of Chemical Vapor-Deposited (CVD) mullite+CVD alumina+plasma-sprayed tantalum oxide coatings on silicon nitride vanes after an industrial gas turbine engine field test
AU - Haynes, J. A.
AU - Zemskova, S. M.
AU - Lin, H. T.
AU - Ferber, M. K.
AU - Westphal, W.
PY - 2006/11
Y1 - 2006/11
N2 - Silicon nitride ceramic vanes coated with chemical vapor-deposited (CVD) mullite, CVD alumina, and plasma-sprayed tantalum oxide were exposed to field tests in an industrial gas turbine engine. Results varied due to expected non-uniformities in the CVD coating microstructures, but dense CVD mullite/alumina showed excellent stability and protective capacity after 1148 h of engine testing. Surfaces without CVD coatings experienced massive intragranular subsurface oxidation and/or rapid recession of the ceramic substrate due to volatilization of silica species formed by oxidation. These results suggest that thin (<5 μm), dense, high-purity CVD mullite and CVD alumina are viable components for an environmental barrier coating system to protect structural ceramics in combustion environments.
AB - Silicon nitride ceramic vanes coated with chemical vapor-deposited (CVD) mullite, CVD alumina, and plasma-sprayed tantalum oxide were exposed to field tests in an industrial gas turbine engine. Results varied due to expected non-uniformities in the CVD coating microstructures, but dense CVD mullite/alumina showed excellent stability and protective capacity after 1148 h of engine testing. Surfaces without CVD coatings experienced massive intragranular subsurface oxidation and/or rapid recession of the ceramic substrate due to volatilization of silica species formed by oxidation. These results suggest that thin (<5 μm), dense, high-purity CVD mullite and CVD alumina are viable components for an environmental barrier coating system to protect structural ceramics in combustion environments.
UR - http://www.scopus.com/inward/record.url?scp=33750280724&partnerID=8YFLogxK
U2 - 10.1111/j.1551-2916.2006.01256.x
DO - 10.1111/j.1551-2916.2006.01256.x
M3 - Article
AN - SCOPUS:33750280724
SN - 0002-7820
VL - 89
SP - 3560
EP - 3563
JO - Journal of the American Ceramic Society
JF - Journal of the American Ceramic Society
IS - 11
ER -