Lifetime Assessment and Shock Behavior of TBC in Gas Turbine Blades: Experimental and Numerical Investigations

Abstract

In this study, the thermal shock behaviour of a thermal barrier coating system of a gas turbine engine’s turbine blade of the space and aircrafts are evaluated. The thermal shock behaviour of the thermal barrier coating system was investigated. Computer-assisted thermal (ANSYS) and crack growth (FCPAS) analyses were carried out with the help of the obtained information. Thermal barrier coating system consists of nickel based superalloy substrate, ytria stabilized zirconia (%8 YSZ) ceramic top coat and NiCrAlY bond coat. Plasma spray method was used for coatings. Damages that occurred in the specimens were assessed according to cycle numbers, thermal stress and heating time. With the aid of the experiments, stress analyses of the modelled TBC were performed. The crack profiles and crack progression rates were determined. Finally the coating life was determined.