Thermal expansion of cladding tubes and rods made of Zr-1% Nb alloy in the temperature range 293-873 K (20-600°C)based on X-ray and dilatometric measurements

Abstract

The temperature dependences of the periods a and c of the crystal structure of a-Zr and thermal linear expansion coefficients (TLEC) of textured cladding tubes and rods of E110opt Zr-based alloy in the axial direction in the temperature range of 293-873 K (20-600 °С) were determined. On the basis of Kearns’ integral texture parameters for cladding tubes and rods, TLEC values were calculated. The calculated values of the TLEC turned out to be significantly smaller than the values measured by the dilatometric method. Simulation of the process of thermal expansion of goods showed that the observed differences in the calculated and measured values of the TLEC can be due to layer-by-layer texture inhomogeneity of tubes and internal stresses arising between the layers.