Determination of residual stresses in zirconia layer using X-ray diffraction and by a micromechanical approach:: thermoelastic anisotropy effect

The determination of residual stresses and the analysis of phases in zirconia layers obtained after oxidation of Zy-4 and Zr-1%Nb-O sheets have been performed using X-ray diffraction with synchrotron radiation at 20 and 400degreesC. These experimental analyses have been compared with calculations using a micromechanical approach (thermoelastic behaviour) and also with a macroscopic approximation of the thermal stress due to cooling. The main result is the small influence of cooling on the residual stresses developing in the zirconia layer, especially for Zr-1%Nb-O.