Investigation of neutron radiation effects on the mechanical behavior of recrystallized zirconium alloys

Neutron radiation induces important changes in the mechanical behavior of recrystallized zirconium alloys used as fuel cladding tube. The neutron radiation effects on the mechanical behavior for internal pressure tests performed at 350 °C have been investigated using a specific analysis in terms of isotropic hardening, kinematic hardening and viscous stress. A unified internal variables modeling has also been used in order to provide a consistent description of the radiation effects on the mechanical behavior. The impact of irradiation has been interpreted in terms of microscopic deformation mechanisms observed by transmission electron microscopy. Due to the localization of the plastic deformation inside channels and because of the only activation of basal channeling, the kinematic hardening is expected to be strong in irradiated zirconium alloys.