Topic: Implementation of Advanced Ceramics and Composites for High Energy Efficiency and Clean Emission Turbine Engines

Over the past decade achieving very low emissions as specified by the environment regulators has become very important for most land-based gas turbines operating near urban center with expectation of NOx and CO in the single digit range. The strategies, by which engine performance (efficiency and output power) can be significantly improved, are to increase the turbine inlet temperature and/or eliminate the cooling that in turn will enhance the reduction of exhaust emissions. Ceramic materials can potentially be used for uncooled hot section components at temperatures approaching 1370°C, compared to about 1000°C for cooled components made of advanced superalloy parts. With ceramic component designs and implementations, much higher turbine operating temperatures can be achieved while eliminating, or greatly reducing, component cooling requirements. Thus, the key driving force behind the efforts to incorporate ceramic materials into gas turbine engines has been the desire to reduce dependence on strategic metals, improve thermal efficiency, increase output power, enhance component durability, lower emissions, and reduce cost. Advanced silicon nitride ceramics as well as SiC-fiber reinforced SiC matrix composites have been the leading candidates for gas turbine engine applications due to their superior thermomechanical properties performance and oxidation resistance at temperatures up to 1400°C in an oxidizing environment. In this lecture, efforts to design ceramic and ceramic composite components for retrofit into a land-based gas turbine engine, and the methodology for probabilistic ceramic component design and implementation carried will be presented. In addition, engine field tests were carried out through the course of program to provide insight into the effect of combustion environment on the long-term stability of ceramics and composites, which could not be readily reproduced in a laboratory scale. The analysis of these ceramic components after these field tests as well as the issues encountered in the gas turbine environment, and potentially remedial solutions to improve the long-term material stability and mechanical reliability will be presented and discussed in the lecture.

Curriculum Vitae-Hua-Tay Lin

Dr. Hua-Tay Lin, Distinguished R&D staff member, Group Lead of Ceramic Science and Technology Group, Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee, is currently focusing researches on mechanical reliability of ceramic components and electronic devices, high-temperature mechanical performance of ceramics and composites, high-temperature steam effects on mechanical reliability of ceramics and environmental barrier coating systems, and engineering of microstructure and properties of ceramics and composites, and coatings. He has served as a PI on numerous programs sponsored by DOE’s Office of Distributed Energy, Office of Electricity Distribution Reliability and Transmission, Office of Transportation Technologies, Office of Industrial Technologies, and Office of Power Technologies with frequent collaborations with researchers at institution in the U. S., Japan, Korea, and Europe.

Dr. Lin is the pass Chair of the Engineering Ceramics Division of the American Ceramic Society. He currently serves on the Journal of Materials Engineering & Performance Committee and Secretary of ASM International, and Publication Committee Chair and as the Editor-in-Chief of the International Journal of Applied Ceramic Technology of the American Ceramic Society. He is a Fellow of the American Ceramic Society (2003), Fellow of ASM International (2006), and Academician of World Academy of Ceramics (2007). He received Martin Marietta Energy Systems Technical Achievement Award for 1991, Martin Marietta Energy Systems Technical Support Awards for Technology Transfer for 1996 and 1993, Lockheed Martin Energy Research Significant Event Award, 1997, a Science and Technology Agency (STA) Fellowship Award to conduct research in Japan in 1998, and the 2007 Outstanding Alumnus Award, Materials Engineering, Auburn University. He is the editor and co-editor of 12 peer-reviewed conference proceedings, and author and co-author of more than 115 peer-reviewed publications.

Dr. Lin holds a M.S. and a Ph.D. in Materials Engineering from Auburn University and a B.S. in Physics from National Central University, Taiwan.