Documents disponibles écrits par cet auteur

Simulations of stress-induced twinning and de-twinning / ShenYang Hu in Acta materialia, Vol. 58 N° 19 (Novembre 2010) 

Public ISBD [article]  in Acta materialia > Vol. 58 N° 19 (Novembre 2010) . - pp. 6554–6564 Titre : Simulations of stress-induced twinning and de-twinning : A phase field model Type de document : texte imprimé Auteurs : ShenYang Hu, Auteur ; Chuck H. Henager Jr, Auteur ; Long-Qing Chen, Auteur Année de publication : 2011 Article en page(s) : pp. 6554–6564 Note générale : Métallurgie Langues : Anglais (eng) Mots-clés : Phase  field  method  Partial  dislocation  Deformation  twin  Polycrystal  deformation Résumé : Twinning in certain metals or under certain conditions is a major plastic deformation mode. Here we present a phase field model to describe twin formation and evolution in a polycrystalline fcc metal under loading and unloading. The model assumes that twin nucleation, growth and de-twinning is a process of partial dislocation nucleation and slip on successive habit planes. Stacking fault energies, energy pathways (γ surfaces), critical shear stresses for the formation of stacking faults and dislocation core energies are used to construct the thermodynamic model. The simulation results demonstrate that the model is able to predict the nucleation of twins and partial dislocations, as well as the morphology of the twin nuclei, and to reasonably describe twin growth and interaction. The twin microstructures at grain boundaries are in agreement with experimental observation. It was found that de-twinning occurs during unloading in the simulations, however, a strong dependence of twin structure evolution on loading history was observed. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410005343 [article] Simulations of stress-induced twinning and de-twinning : A phase field model [texte imprimé] / ShenYang Hu, Auteur ; Chuck H. Henager Jr, Auteur ; Long-Qing Chen, Auteur . - 2011 . - pp. 6554–6564. Métallurgie Langues : Anglais (eng) in Acta materialia > Vol. 58 N° 19 (Novembre 2010) . - pp. 6554–6564 Mots-clés : Phase  field  method  Partial  dislocation  Deformation  twin  Polycrystal  deformation Résumé : Twinning in certain metals or under certain conditions is a major plastic deformation mode. Here we present a phase field model to describe twin formation and evolution in a polycrystalline fcc metal under loading and unloading. The model assumes that twin nucleation, growth and de-twinning is a process of partial dislocation nucleation and slip on successive habit planes. Stacking fault energies, energy pathways (γ surfaces), critical shear stresses for the formation of stacking faults and dislocation core energies are used to construct the thermodynamic model. The simulation results demonstrate that the model is able to predict the nucleation of twins and partial dislocations, as well as the morphology of the twin nuclei, and to reasonably describe twin growth and interaction. The twin microstructures at grain boundaries are in agreement with experimental observation. It was found that de-twinning occurs during unloading in the simulations, however, a strong dependence of twin structure evolution on loading history was observed. DEWEY : 669 ISSN : 1359-6454 En ligne : http://www.sciencedirect.com/science/article/pii/S1359645410005343