Characterization of the post-necking strain hardening behavior using the virtual fields method

INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES

卷:50

Article

Kim, J. -H.¹  Serpantie, A.²  Barlat, F.¹  Pierron, F.³  Lee, M. -G.¹ 

[1] Pohang Univ Sci & Technol, GIFT, Pohang 790784, Gyeongbuk, South Korea

[2] Arts & Metiers ParisTech, LMPF, F-51006 Chalons Sur Marne, France

[3] Univ Southampton Highfield, Fac Engn & Environm, Southampton SO17 1BJ, Hants, England

关键词: Full-field measurement;    Virtual fields method;    Elasto-plastic behaviour;    Isotropic hardening;    Inverse problem;    Advanced high strength steel;   

DOI  :  10.1016/j.ijsolstr.2013.07.018

来源: Elsevier

【 摘 要 】

The present study aims at characterizing the post-necking strain hardening behavior of three sheet metals having different hardening behavior. Standard tensile tests were performed on sheet metal specimens up to fracture and heterogeneous logarithmic strain fields were obtained from a digital image correlation technique. Then, an appropriate elasto-plastic constitutive model was chosen. Von Mises yield criterion under plane stress and isotropic hardening law were considered to retrieve the relationship between stress and strain. The virtual fields method (VFM) was adopted as an inverse method to determine the constitutive parameters by calculating the stress fields from the heterogeneous strain fields. The results show that the choice of a hardening law which can describe the hardening behavior accurately is important to derive the true stress-strain curve. Finally, post-necking hardening behavior was successfully characterized up to the initial stage of localized necking using the VFM with Swift and modified Voce laws. (C) 2013 Elsevier Ltd. All rights reserved.

【 授权许可】

Free