Multiscale modeling of the elasto-plastic behavior of architectured and nanostructured Cu-Nb composite wires and comparison with neutron diffraction experiments
Résumé
Nanostructured and architectured copper niobium composite wires are excellent candidates for
the generation of intense pulsed magnetic fields ( 100T) as they combine both high strength and
high electrical conductivity. Multi-scaled Cu-Nb wires are fabricated by accumulative drawing
and bundling (a severe plastic deformation technique), leading to a multiscale, architectured, and
nanostructured microstructure exhibiting a strong fiber crystallographic texture and elongated
grain shape along the wire axis. This paper presents a comprehensive study of the effective elastoplastic
behavior of this composite material by using two different approaches to model the microstructural
features: full-field finite elements and mean-field modeling. As the material exhibits
several characteristic scales, an original hierarchical strategy is proposed based on iterative scale
transition steps from the nanometric grain scale to the millimetric macro-scale. The best modeling
strategy is selected to estimate reliably the effective elasto-plastic behavior of Cu-Nb wires
with minimum computational time. Finally, for the first time, the models are confronted to
tensile tests and in-situ neutron diffraction experimental data with a good agreement.
Domaines
Matériaux
Origine : Fichiers produits par l'(les) auteur(s)