A new approach to determine the zircaloy constitutive equations under irradiation

This work is concerned with the determination of the constitutive relations for polycrystalline zircaloy under irradiation. We try to obtain a formulation in which most of the involved parameters can be related to the mechanisms responsible for the deformation. The method is divided into two steps: the determination and definition of the deformation mechanisms, associated with a modelling procedure in order to obtain local laws governing the behaviour of the single crystal, and then a homogenization step providing the constitutive equations for polycrystals. (author)