Effect of the thickness of plasma-sprayed coating on bond strength and thermal fatigue characteristics

Abstract

NiCrAlY bond coat and ZrO2-8 wt % Y2O3 top coat With various thicknesses were deposited on Hastelloy X by plasma spraying. Residual stress was calculated by the finite element method (FEM) to explain the variations in the bond strength and thermal fatigue characteristics with the thickness of the bond coat and top coat. The bond strength of thermal barrier coatings (TBCs) increased with decreasing maximum residual stress in the y-direction of the top coat. The thermal fatigue characteristics increased with decrease of the maximum principal residual stress of the top coat and the thickness of oxidation layer of the bond coat. (C) 1998 Kluwer Academic Publishers.