Thermal Barrier Coating Materials Review

Abstract

The priority technological direction of thermal protection of hot section components, basically turbine parts is the development of thermal barrier coatings (TBCs) in order to improve the operational performance of aero gas turbine engines (GTEs). The application of this coating, which can lower the surface temperature of the substrate material and have high oxidation resistance, was of great importance. The focus of this paper is on choosing TBCs with lower conductivity and longer life than coatings used in industry today and on the study of the effect of TBCs with low thermal conductivity on the longevity and performance of the GTE. Although this type of coating consists of multilayers, here only an overview of the coating materials used in their top layer is given. This review is based essentially on the thermal and mechanical properties of these materials. Although there are many oxide materials that meet the specified requirements and are considered suitable for use as a ceramic top layer in the TBC system, the most promising one was selected. Compared to traditional TBC systems, it is a pyrochlore type oxide with very low thermal conductivity, high thermal stability, and some other advantages - Lanthanum zirconate (La2Zr2O7, LZ).

Keywords

• aero gas turbine engine
• thermal barrier coating
• top coat
• novel ceramics
• thermal and mechanical properties