Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-24T15:34:04.343Z Has data issue: false hasContentIssue false

Stability Study of EBC/TBC Hybrid System on Si-based Ceramics in Gas Turbines

Published online by Cambridge University Press:  07 January 2013

JiaPeng Xu
Affiliation:
Division of Materials Science and Engineering, Boston University, Brookline, MA 02446, USA
Vinod Sarin
Affiliation:
Division of Materials Science and Engineering, Boston University, Brookline, MA 02446, USA Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA
Soumendra Basu
Affiliation:
Division of Materials Science and Engineering, Boston University, Brookline, MA 02446, USA Department of Mechanical Engineering, Boston University, Boston, MA 02215, USA
Get access

Abstract

Currently, ceramics are being used under increasingly demanding environments. These materials have to exhibit phase stability and resist chemical attack during service. This research involves the study of the high-temperature stability of ceramic materials in gas turbines. SiC/SiC ceramic matrix composites (CMCs) are being increasingly used in the hot-sections of gas turbines, especially for aerospace applications. These CMCs are prone to recession of their surface if exposed to a flow of high-velocity water vapor, and to hot-corrosion when exposed to molten alkali salts. The objective of this investigation was the development of a hybrid system containing an environmental barrier coating (EBC) for protection of the CMC from chemical attack and a thermal barrier coating (TBC) that allows a steep temperature gradient across it to lower the temperature of the CMC for increased lifetimes. The EBC used was a functionally graded mullite (3Al2O3∙2SiO2) coating deposited by chemical vapor deposition (CVD), while the TBC layer was yttria-stabilized zirconia (YSZ) deposited by air plasma spray (APS). The stability of this system was investigated, via adhesion between the two coating layers and the substrate, the physical and chemical stability of each layer at high temperature, and the performance under severe thermal shock and exposure to hot corrosion.

Type
Articles
Copyright
Copyright © Materials Research Society 2012

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Robinson, R., “SiC recession caused by SiO2 scale volatility under combustion conditions: I, experimental results and empirical model,” Journal of The American Ceramic, vol. 25, no. 190288, pp. 18171825, 1999.10.1111/j.1151-2916.1999.tb02004.xCrossRefGoogle Scholar
Eaton, H. E. and Linsey, G. D., “Accelerated oxidation of SiC CMC ’ s by water vapor and protection via environmental barrier coating approach,” vol. 22, pp. 2741–2747, 2002.Google Scholar
Smialek, J. L. and Jacobson, N. S., “Mechanism of Strength Degradation for Hot Corrosion of a-Sic,” vol. 52, 1986.10.1002/chin.198703022CrossRefGoogle Scholar
Jones, R. L., “Some Aspects of the Hot Corrosion of Thermal Barrier Coatings,” vol. 6, no. March, pp. 77–84, 1997.10.1007/BF02646315CrossRefGoogle Scholar
Bhatia, T., Eaton, H., Holowczak, J., and Sun, E., “Development and Evaluation of Environmental Barrier Coatings for Silicon Nitride,” DOE EBC Workshop in, 2003.Google Scholar
Lee, K. and Miller, R., “New Generation of Plasma‐Sprayed Mullite Coatings on Silicon Carbide,” Journal of the American Ceramics Society, vol. 78, no. 3, pp. 705710, 1995.10.1111/j.1151-2916.1995.tb08236.xCrossRefGoogle Scholar
Lee, K. N. and Miller, R. A., “Development and environmental durability of mullite and mullite/YSZ dual layer coatings for SiC and Si3N4 ceramics,” Surface and Coatings Technology, vol. 8687, no. 1–3, pp. 142148, 1996.10.1016/S0257-8972(96)03074-5CrossRefGoogle Scholar
Lee, K., “Contamination Effects on Interfacial Porosity during Cyclic Oxidation of Mullite‐Coated Silicon Carbide,” Journal of the American Ceramic Society, vol. 32, pp. 33293332, 1998.10.1111/j.1151-2916.1998.tb02777.xCrossRefGoogle Scholar
Lee, K., “Key durability issues with mullite-based environmental barrier coatings for Si-based ceramics,” Journal of engineering for gas turbines and power, vol. 122, no. October, pp. 632636, 2000.10.1115/1.1287584CrossRefGoogle Scholar
Lee, K. N., “Current status of environmental barrier coatings for Si-Based ceramics,” Surface and Coatings Technology, vol. 133134, pp. 17, Nov. 2000.Google Scholar
Zhu, D., Bansal, N., and Lee, K., “Thermal conductivity of ceramic thermal barrier and environmental barrier coating materials,” NASA TM-211122, NASA Glenn, no. September, 2001.Google Scholar
Auger, M. and Sarin, V., “The development of CVD mullite coatings for high temperature corrosive applications,” Surface and Coatings Technology, vol. 95, pp. 4652, 1997.10.1016/S0257-8972(97)00474-XCrossRefGoogle Scholar
Basu, S. N., Kulkarni, T., Wang, H. Z., and Sarin, V. K., “Functionally graded chemical vapor deposited mullite environmental barrier coatings for Si-based ceramics,” Journal of the European Ceramic Society, vol. 28, no. 2, pp. 437445, Jan. 2008.10.1016/j.jeurceramsoc.2007.03.007CrossRefGoogle Scholar
Kulkarni, T., Wang, H. Z., Basu, S. N., and Sarin, V. K., “Compositionally graded mullite-based chemical vapor deposited coatings,x201d; Journal of Materials Research, vol. 24, no. 02, pp. 470474, Jan. 2011.10.1557/JMR.2009.0062CrossRefGoogle Scholar
Kulkarni, T., Wang, H. Z., Basu, S. N., and Sarin, V. K., “Protective Al-rich mullite coatings on Si- based ceramics against hot corrosion at 1200°C,” Surface and Coatings Technology, vol. 205, no. 10, pp. 33133318, Feb. 2011.10.1016/j.surfcoat.2010.11.055CrossRefGoogle Scholar
Xu, J., Dixit, S., Sarin, V., and Basu, S., “CVD Mullite Coating as EBC of EBC/TBC Dual Coating System for SiC/SiC Ceramic Matrix Composite Materials,” Manuscript in preparation.Google Scholar