Porous polycrystal plasticity modeling of neutron-irradiated austenitic stainless steels

JOURNAL OF NUCLEAR MATERIALS

卷:542

Article

Vincent, Pierre-Guy¹  Moulinec, Herve²  Joessel, Louis¹  Idiart, Martin I.^3,4  Garajeu, Mihail² 

[1] Inst Radioprotect & Surete Nucl, BP 3, F-13115 St Paul Les Durance, France

[2] Aix Marseille Univ, CNRS, Cent Marseille, LMA, 4 Impasse Nikola Tesla,CS 40006, F-13453 Marseille 13, France

[3] Univ Nacl La Plata, Dept Aeronciut, Fac Ingn, Ctr Tecnol Aerosp, Avda 1 Esq 47 S-N,B1900TAG, La Plata, Argentina

[4] Consejo Nacl Invest Cient & Tecn, CCT La Plata, Calle 8 1467,B1904CMC,B1904CMC, La Plata, Argentina

关键词: Crystal plasticity;    Irradiation hardening;    Void swelling;    Fast Fourier Transforms simulations;    Austenitic stainless steel;    Micromechanics of porous media;   

DOI  :  10.1016/j.jnucmat.2020.152463

来源: Elsevier

【 摘 要 】

A micromechanical model for quantifying the simultaneous influence of irradiation hardening and swelling on the mechanical stiffness and strength of neutron-irradiated austenitic stainless steels is proposed. The material is regarded as an aggregate of equiaxed crystalline grains containing a random dispersion of pores (large voids due to large irradiation levels) and exhibiting elastic isotropy but viscoplastic anisotropy. The overall properties are obtained via a judicious combination of various bounds and estimates for the elastic energy and viscoplastic dissipation of voided crystals and polycrystals. Reference results are generated with full-field numerical simulations for dense and voided polycrystals with periodic microstructures and crystal plasticity laws accounting for the evolution of dislocation and Frank loop densities. These results are calibrated with experimental data available from the literature and are employed to assess the capabilities of the proposed model to describe the evolution of mechanical properties of highly irradiated Solution Annealed 304L steels at 330 degrees C. The agreement between model predictions and simulations is seen to be quite satisfactory over the entire range of porosities and loadings investigated. The expected decrease of overall elastic properties and strength for porosities observed at large irradiation levels is reported. The mathematical simplicity of the proposed model makes it particularly apt for implementation into finite-element codes for structural safety analyses. (C) 2020 Elsevier B.V. All rights reserved.

【 授权许可】

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