Advanced Oxide Material Systems For 1650 C Thermal/Environmental Barrier Coating Applications

Advanced thermal/environmental barrier coatings (T/EBCs) are being developed for low emission SiC/SiC ceramic matrix composite (CMC) combustor and vane applications to extend the CMC liner and vane temperature capability to 1650 C (3000 F) in oxidizing and water-vapor containing combustion environments. The 1650 C T/EBC system is required to have better thermal stability, lower thermal conductivity, and improved sintering and thermal stress resistance than current coating systems. In this paper, the thermal conductivity, water vapor stability and cyclic durability of selected candidate zirconia-/hafnia-, pyrochlore- and magnetoplumbite-based T/EBC materials are evaluated. The test results have been used to downselect the T/EBC coating materials, and help demonstrate advanced 1650OC coatings feasibility with long-term cyclic durability.