Effect of Substrate Condictions on Thermal Shock Property of Plasma-spraying Sm2Zr2O7/YSZ Thermal Barrier Coatings

Effect of substrate conditions, including material type, thickness and radius of substrate, on thermal-shocking stresses of plasma spraying Sm2Zr2O7/YSZ TBCs was analyzed through finite element method. Results show that radial stresses decrease with time increasing, and they decrease with the increasing of distance from center to edge along radius. However, axial residual stresses increse abruptly at the edge of specimen. All residual stresses increse with incresing of thermal expansion coefficient of substrate. Radial stresses increase with substrate thickness increasing, however, they are not effectd by substrate thickness if it is great than 25mm. and axial residual stresses and shear stresses are not effected by the substrate thickness. The maximum values of axial stresses and shear stresses were not effected by sustrate radius, and values of radial stresses remian invariable when substrate radius is over 18mm.