MEMS/NEMS High Temperature Thermal Barrier Coatings

We propose to develop a potentially revolutionary technological innovation that will significantly increase the efficiency, lifetime and reliability of gas-turbine engines. Despite the tremendous improvements in coating technologies to enable huge increases in operational temperatures, continued advances using conventional, purely materials-science approaches have resulted in diminishing marginal returns in the last 25 years. The problem is that the turbine blades heat up as a result of conductive and radiative heat transport. Using MEMS-fabrication methods, we will develop a technique to imbed structure within the thermal-barrier coatings (TBCs) currently bonded to turbine blades that will decrease the thermal conductivity by a factor of 2, thereby attenuating phonon transport of heat and providing the means to (1) increase turbine-blade lifetime and (2) attain considerably higher operating efficiencies by operating the engines at significantly higher temperatures. In Phase I we will (1) fully characterize and design the requisite imbedded structure; and (2) fabricate test samples and measure the decrease in their thermal conductivity. In Phase II we will demonstrate an optimal system—fabricated utilizing MEMS technology—that is designed to minimize phonon heat transport in materials that are appropriate for TBCs.