Zirconia-Based Thermal Barrier Coatings Systems for Aero-Industry

Intelligent thermal spray processing is vital in many fields with high-temperature applicability for efficient production. For aircraft turbo engines in the aeronautical industry, temperatures above 1000 °C are demanded, as well as thermal shock, erosive and corrosive wear, sliding friction. All of those hard conditions indicate the need for the development of protective solutions with optimal properties of interface and volume to which is added the appropriate chemical and mechanical stability. Two of the benefits of thermal protection layers are low diffusivity and low expansion coefficient. However, at the interface between the bonding layer and the ceramic layer, an intermediate oxide layer, named TGO (Thermally Grown Oxide), is formed, which is a weak spot in the system. The monitoring of thermo–physical properties together with morphostructural investigations allowed the evaluation of the structure characteristics of obtained ceramic materials, emphasizing the need for reduced thermal conductivity as well as the critical need to predict the life span. This chapter will provide a short review on the present status of the research of ceramics composites coatings used as thermal barrier for industrial hot structural components, their lates advanced in fabrication and performance, as well as recommendation of their use in harsh high-temperature environments.