Emittance of Y2O3 stabilised ZrO2 thermal barrier coatings prepared by electron-beam physical-vapour deposition
Jochen Manara, Rainer Brandt, Joachim Kuhn, Jochen Fricke, Thomas Krell, Uwe Schulz, Manfred Peters, Wolfgang Kaysser
Electron-beam physical-vapour deposited (EB-PVD) thermal barrier coatings are used in aircraft and land-based gas turbines for thermal insulation of thermally highly loaded components like turbine blades. Conventional duplex thermal barrier coatings (TBCs) consist of two different layers. A partially yttria stabilised zirconia top coat serves as thermal barrier while a NiCrAlY or CoCrAlY bond coat below provides adhesion and oxidation protection of the metallic substrate. The ceramic top coat shows a columnar microstructure which offers some advantages in comparison to plasma-sprayed TBCs.