|About this Abstract
||MS&T23: Materials Science & Technology
||Advanced Coatings for Wear and Corrosion Protection
||Novel Thermal Barrier Coatings Stable up to 1700°C
||Melina A. Endsley, Collin S. Holgate, Akane Suzuki, Joshua L. Margolies, Carlos G. Levi, Tresa M. Pollock
|On-Site Speaker (Planned)
||Melina A. Endsley
The demand for higher temperature components that can replace superalloys in gas turbines, enabling continued improvements in efficiency, motivates the need for advanced TBCs that can operate at temperatures as high as 1700°C, representing 450-500°C increments over current systems. In one concept, the proposed structural component is based on RMPEAs, and oxidation protection is provided by an alumina forming bond coat. Hence, the TBC must be thermochemically compatible with alumina at temperatures up to ~1400°C and tolerate thermal strains owing to mismatch with the substrate. Novel TBC compositions based on rare-earth stabilized HfO2 or ZrO2 have been synthesized and investigated using diffusion couples, electron microscopy, and dilatometry, and microindentation. While the compositions initially investigated exhibit shortcomings in terms of compatibility with alumina, mitigating strategies using bilayer coatings were implemented and will be discussed. The dilatometry results reveal promising CTEs for the implementation of these TBCs into a larger substrate-coating system.