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Title: Nondestructive evaluation of environmental barrier coatings in CFCC combustor liners.

Abstract

Advanced combustor liners fabricated of SiC/SiC continuous fiber-reinforced ceramic composite (CFCC) and covered with environmental barrier coatings (EBCs) have been successfully tested in Solar Turbines Inc. field engines. The primary goal for the CFCC/EBC liners is to reach a 30,000-h lifetime. Because the EBCs, when applied on the hot surfaces of liners, protect the underlying CFCC from oxidation damage, their performance is critical in achieving the lifetime goal. To determine CFCC/EBC liner condition and assess operating damage, the liners were subjected to nondestructive evaluation (NDE) during various processing stages, as well as before and after the engine test. The NDE techniques included pulsed infrared thermal imaging, air-coupled ultrasonic scanning, and X-ray computerized tomography. It was found that EBC damage and spallation depend on the condition of the CFCC material. The NDE results and correlations with destructive examination are discussed.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
EE
OSTI Identifier:
942101
Report Number(s):
ANL/ET/CP-117333
TRN: US200825%%658
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Conference
Resource Relation:
Conference: 30th Annual International Conference & Expositon on Advanced Ceramics and Composites; Jan. 22, 2006 - Jan. 27, 2006; Cocoa Beach, FL
Country of Publication:
United States
Language:
ENGLISH
Subject:
36 MATERIALS SCIENCE; 42 ENGINEERING; SILICON CARBIDES; COMPOSITE MATERIALS; REINFORCED MATERIALS; FIBERS; PROTECTIVE COATINGS; COMBUSTORS; LINERS; OXIDATION; NONDESTRUCTIVE TESTING

Citation Formats

Sun, J. G., Benz, J., Ellingson, W. A., Kimmel, J. B., Price, J. R., Energy Technology, and Solar Turbines, Inc. Nondestructive evaluation of environmental barrier coatings in CFCC combustor liners.. United States: N. p., 2007. Web.
Sun, J. G., Benz, J., Ellingson, W. A., Kimmel, J. B., Price, J. R., Energy Technology, & Solar Turbines, Inc. Nondestructive evaluation of environmental barrier coatings in CFCC combustor liners.. United States.
Sun, J. G., Benz, J., Ellingson, W. A., Kimmel, J. B., Price, J. R., Energy Technology, and Solar Turbines, Inc. Mon . "Nondestructive evaluation of environmental barrier coatings in CFCC combustor liners.". United States. doi:.
@article{osti_942101,
title = {Nondestructive evaluation of environmental barrier coatings in CFCC combustor liners.},
author = {Sun, J. G. and Benz, J. and Ellingson, W. A. and Kimmel, J. B. and Price, J. R. and Energy Technology and Solar Turbines, Inc},
abstractNote = {Advanced combustor liners fabricated of SiC/SiC continuous fiber-reinforced ceramic composite (CFCC) and covered with environmental barrier coatings (EBCs) have been successfully tested in Solar Turbines Inc. field engines. The primary goal for the CFCC/EBC liners is to reach a 30,000-h lifetime. Because the EBCs, when applied on the hot surfaces of liners, protect the underlying CFCC from oxidation damage, their performance is critical in achieving the lifetime goal. To determine CFCC/EBC liner condition and assess operating damage, the liners were subjected to nondestructive evaluation (NDE) during various processing stages, as well as before and after the engine test. The NDE techniques included pulsed infrared thermal imaging, air-coupled ultrasonic scanning, and X-ray computerized tomography. It was found that EBC damage and spallation depend on the condition of the CFCC material. The NDE results and correlations with destructive examination are discussed.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}

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