The morphology of Portevin-Le Chatelier bands: Finite element simulation for Al-Mg-Si

Citation
S. Zhang et al., The morphology of Portevin-Le Chatelier bands: Finite element simulation for Al-Mg-Si, ACT MATER, 49(6), 2001, pp. 1087-1094
Citations number
18
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
ACTA MATERIALIA
ISSN journal
1359-6454 → ACNP
Volume
49
Issue
6
Year of publication
2001
Pages
1087 - 1094
Database
ISI
SICI code
1359-6454(20010402)49:6<1087:TMOPCB>2.0.ZU;2-X
Abstract
A constitutive model for dynamic strain ageing together with a three-dimens ional finite element analysis were used to simulate discontinuous yielding behaviour associated with the Portevin-Le Chatelier effect. The deformation behaviour of both fiat and round specimens of a dynamically strain ageing material was simulated, utilizing constitutive parameters for an Al-Mg-Si a lloy. Finite element simulations showed the occurrence of propagative zones of localized deformation and provided insight into the strain rate distrib ution in the zones, characterized by a sharp strain rate peak. The localize d deformation zones in round specimens were found to have a diffuse double cone morphology. Propagative deformation bands in flat strip specimens were planar and inclined with respect to the tensile axis by approximately 35 d egrees. The dependence of the morphology of the localized deformation zones on specimen geometry and deformation conditions, as well as the serrated s tress-time curves obtained, are in good agreement with experimental measure ments in Al-Mg-Si. (C) 2001 Acta Materialia Inc. Published by Elsevier Scie nce Ltd. All rights reserved.