Accéder directement au contenu Accéder directement à la navigation
Article dans une revue

A two-site mean field model of discontinuous dynamic recrystallization

Abstract : The paper describes a new model of discontinuous dynamic recrystallization (DDRX) which can operate in constant or variable thermomechanical conditions. The model considers the elementary physical phenomena at the grain scale such as strain hardening, recovery, grain boundary migration, and nucleation. The microstructure is represented through a set of representative grains defined by their size and dislocation density. It is linked to a constitutive law giving access to the polycrystal flow stress. Interaction between representative grains and the surrounding material is idealized using a two-site approach whereby two homogeneous equivalent media with different dislocation densities are considered. Topological information is incorporated into the model by prescribing the relative weight of these two equivalent media as a function of their volume fractions. This procedure allows accounting for the well-known necklace structures. The model is applied to the prediction of DDRX in 304 L stainless steel, with parameters identified using an inverse methodology based on a genetic algorithm. Results show good agreement with experimental data at different temperatures and strain rates, predicting recrystallization kinetics, recrystallized grain size and stress-strain curve. Parameters identified with one initial grain size lead to accurate results for another initial grain size without introducing any additional parameter.
Type de document :
Article dans une revue
Liste complète des métadonnées

https://hal-mines-paristech.archives-ouvertes.fr/hal-00612438
Contributeur : Magalie Prudon <>
Soumis le : vendredi 29 juillet 2011 - 09:24:13
Dernière modification le : mercredi 14 octobre 2020 - 03:47:56

Identifiants

Citation

P. Bernard, Swarup Bag, Ke Huang, Roland E. Logé. A two-site mean field model of discontinuous dynamic recrystallization. Materials Science and Engineering: A, Elsevier, 2011, 528 (24), pp.7357-7367. ⟨10.1016/j.msea.2011.06.023⟩. ⟨hal-00612438⟩

Partager

Métriques

Consultations de la notice

287