Isothermal Oxidation and Thermal Shock Resistance of Thick and Porous LaMgAl11O19 Abradable Topcoat
Author:
Huang Jingqi1ORCID, Chen Wenbo1, Lu Xiangrong1, Xu Mingyi1, Li Gui1, Deng Longhui1, Jiang Jianing1, Dong Shujuan1, Liu Li1, Chen Meizhu1, Cao Xueqiang1
Affiliation:
1. State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan 430070, China
Abstract
An exploration of the plasma-sprayed abradable sealing coatings (ASCs) of a thick and porous LaMgAl11O19 topcoat onto SiC/SiC ceramic matrix composites (CMCs) is detailed in this study. Interlayers comprising Si/Si + Yb2Si2O7/Yb2SiO5 environmental barrier coatings (EBCs) were strategically employed, considering their function in protecting the SiC/SiC CMCs from recession and mitigating thermal expansivity misfit. An isothermal oxidation test was conducted at 1300 °C and resulted in the formation of bubble and glassy melt on the side surface of the coated sample, while a significant reaction layer emerged at the Yb2SiO5/LaMgAl11O19 interface near the edge. The localized temperature rise caused by the exothermic oxidation of the SiC/SiC substrate was determined to be the underlying factor for bubble generation. The temperature-dependent viscosity of the melt contributed to various bubble characteristics, and due to the enrichment of Al ions, the glassy melt exacerbated the degradation of the Yb2SiO5 layer. After a thermal shock test at 1300 °C, the substrate on the uncoated backside of the sample experienced fracture, while the front coating remained intact. However, due to the presence of a through-coating crack, an internal crack network also developed within the substrate.
Funder
National Natural Science Foundation of China Major Program (JD) of Hubei Province Key Research and Development Program of Hubei Province
Reference49 articles.
1. Sporer, D., Wilson, S., Giovannetti, I., Refke, A., and Giannozzi, M. (2007). Tur-Bine Seal Applications, Proceedings of the Thirty-Sixth Turbomachinery Symposium, Houston, TX, USA, 10–13 September 2007, Texas A&M University, Turbomachinery Laboratories. 2. Dorfman, M.R., Fiala, P., Hajmrle, K., and Wilson, S. (2007, January 14–17). Future Abradable Requirements Needed by Aerospace OEM’s and Their Material and Equipment Suppliers. Proceedings of the ASME Turbo Expo, Montreal, QC, Canada. 3. Novinski, E.R. (1989, January 27–30). The Selection and Performance of Thermal Sprayed Abradable Seal Coatings for Gas Turbine Engines. Proceedings of the Annual Aerospace/Airline Plating and Metal Finishing Forum and Exposition, New Orleans, LA, USA. 4. Ceramics for Abradable Shroud Seal Applications;Sporer;Ceram. Eng. Sci. Proc.,2009 5. Ceramic materials for thermal barrier coatings;Cao;J. Eur. Ceram. Soc.,2004
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