Influence of Hydride Orientation on the Deformation of Tubes Made of E635 Zirconium Alloy

Abstract—A technique for numerically simulating the influence of zirconium hydride orientation on deformation and local strain distribution in tubes made of Zr–Nb–Sn–Fe (E635) zirconium-based alloy is described. Simulation has been performed by the finite-element method embedded in the ANSYS software package by taking into account the crystal texture in the material at room temperature. It has been shown that radially oriented hydrides cause sharper stress variation than those oriented tangentially. It has been confirmed that the dependence of von Mises maximal stress on hydride orientation factor Fn in the tube is S‑shaped, which indicates the presence of the ductile-to-brittle transition in the interval Fn = 0.20–0.35. Simulation results agree with experimental data, so that the suggested technique may be considered applicable for predicting the mechanical properties of hydrogenated tubes made of zirconium alloys.