Assessment of zirconia thermal barrier coatings on austenitic steel

Abstract

The need to increase the efficiency of aerodynamic engines and last generation turbines (t>1200o C) have imposed new types of materials and coating techniques for the realization of thermal barriers (TBCs). Yttria-doped zirconia (YSZ)-based TBCs are now competing with new materials to provide durability and reliability. The research is focused on the development of new TBC manufacturing techniques to improve the performance of YSZ. A layer of zirconia, without intermediate thermally grown oxide (TGO), with micrometric thickness of the deposition on an austenitic steel support, multilayered and doped with nanometric particles in two phases, was investigated non-destructively. The results obtained on the quality and adhesion to the support obtained by X ray diffraction (XRD) and scanning electron microscopy (SEM) are compared with the electromagnetic ones (EM).