A constitutive law for the mechanical behavior of Zr 702α

Abstract A phenomenological law is proposed for the description of the mechanical behavior of Zr 702α. The identification of the parameters of the constitutive law, from macroscopic stress–strain curves of polycrystalline samples deformed in channel die compression at room temperature, indicates a good description of experiment. The implementation of the phenomenological law into a finite element code, with a Coulomb law for a more realistic description of the experimental conditions, shows good agreements between the experimental and calculated curves, and allows to describe the evolution of stress heterogeneities and of the parameters of the identified law in the samples with the plastic deformation. Moreover, the analysis of the identified parameters, from calculations performed with a self-consistent model with the initial textures of the analyzed samples, confirms the role of the active deformations modes during plastic deformation.

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