Advanced NZP-Ceramic Based Thermal Barrier Coatings with Enhanced Oxidation and Thermal Shock Resistance

99 Advanced NZP-Ceramic Based Thermal Barrier Coatings with Enhanced Oxidation and Thermal Shock Resistance--LoTec, Inc., 181 West 1700 South, Salt Lake City, UT 84115-5247; (801) 483-3100 Mr. Ramachandran Nageswaran, Principal Investigator Mr. Santosh Y. Limaye, Business Official DOE Grant No. DE-FG03-97ER82418 Amount: $74,900 High performance thermal barrier coating (TBCs) are becoming increasingly essential for meeting temperature and insulation requirements of next generation gas turbines, aircraft, and diesel engines. Higher firing temperatures for improved efficiency, better insulation, and prolonged life of components in power generation systems and aerospace engines are required. Conventional thermal barrier coatings based on yttria partially-stabilized zirconia (YPSZ) are inadequate to meet these exacting requirements, primarily because of their susceptibility to oxidation and spalling, and low thermo-chemical stability. This project is to develop oxidation resistant and durable sodium zirconium phosphate (NZP) ceramics-based TBCs. A functionally-graded design approach will be used to minimize expansion mismatches and to introduce beneficial surface compressive stresses. In Phase I, the majority of the work will be related to thermal spray process development, identification of NZP materials that are most suitable for TBCs, and establishment of a suitable gradient-layer design. Phase II activity will involve comprehensive modeling, testing, and optimization of the ¿TBC-worthy¿ NZP compositions and the NZP-based coating design. Commercial Applications and Other Benefits as described by the awardee: Specific commercial applications could be immediately realized for NZP ceramics based TBCs for turbine blades, combustor liners, stator vanes, etc.; jet and gas turbine engines; and pistons, valve heads, exhaust ports, and cylinders in diesel engines. Other commercial applications are in heat exchangers, burner nozzles, hot gas fans and filters, and pump and valve linings in corrosive environments.