Thermal barrier coating with improved durability: An overview of doped, nanostructured, multilayered, and gradient-structured zirconia-based thermal barrier coatings

The protection of hot structures in modern turbine engines significantly relies on thermal barrier coatings (TBCs). Considering the growing demand for enhanced gas turbine efficiency, researchers worldwide have focused on developing new TBC architectures to overcome the limitations of conventional yttria-stabilized zirconia (YSZ) TBCs. Among the various designs, doped, nanostructured, multilayered, and functionally graded zirconia (ZrO2)-based TBC structures have emerged as highly favorable choices, offering optimal coating performance and durability. This article provides an in-depth overview of conventional TBCs, and their limitations, and investigates various modified ZrO2-based TBCs. The performance of these modified TBCs is evaluated in terms of thermal stability, thermal conductivity, and other relevant characteristics.