Preparation Methods and Ceramic Materials Selection Guideline for Thermal Barrier Coatings

Thermal barrier coatings (TBCs) are usually applied in aviation and power generation industries, particularly in the gas-turbine engines for power generation. The most common methods for TBCs production include electron beamphysical vapor deposition (EB-PVD) and plasma spraying (PS). The PS TBCs usually show the laminar structure with abundant pores and cracks, whereas the EB-PVD TBCs possess excellent anti-corrosion and anti-oxidation capacities with higher thermal conductivity than PS TBCs. In this review, recent progress on microstructure optimization and failure problems based on the EB-PVD and PS methods was summarized. Several available approaches such as the PS-physical vapor deposition method, solution precursor PS, and suspension PS were reviewed. The ceramic materials selection of TBCs was further discussed. In addition to the YSZ system, the pyrochlore structure considered to be the most potential candidate in the next generation was shown in EP2407579 and EP0992603. Other alternatives, such as YAG-based materials, La-Monazite, and LaMgAl11O19, were shown in US2011236657, US6863999, and CN101928144, respectively. Finally, a number of US patents were discussed, including US5773141, US20120219808, and US20120034491 related to the modified TBCs resistant to environmental pollutants called calcium-alumina-silicate.