首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Modeling and Simulation of the Portevin-Le Chatelier Effect
Authors:Albrecht Bertram  Thomas Böhlke  Carina Brüggemann  Yuri Estrin  Mikhail Lebyodkin
Institution:1. Institut für Mechanik, Otto-von-Guericke-Universität Magdeburg, Postfach 4120, D-39016 Magdeburg, Germany;2. Institut für Mechanik, Otto-von-Guericke-Universität Magdeburg, Postfach 4120, D-39016 Magdeburg, Germany

Institut für Mechanik, Fachbereich Maschinenbau, Universität Kassel, D-34109 Kassel, Germany;3. Institut für Werkstoffkunde und Werkstofftechnik, Technische Universität Clausthal, D-38678 Clausthal-Zellerfeld, Germany

Abstract:During deformation of an Al-Mg alloy (AA5754) dynamic strain aging occurs in a certain range of temperatures and strainrates. An extreme manifestation of this phenomenon, usually referred to as the Portevin-Le Chatelier (PLC) effect, consists in the occurrence of strain localisation bands accompanied with discontinuous yielding. The PLC effect stems from dynamic dislocation-solute interactions and results in negative strain-rate sensitivity of the flow stress. The PLC effect is detrimental to the surface quality of sheet metals and also affects the ductility of the material. Since the appearance of the effect strongly depends on the triaxiality of the stress state, three-dimensional finite element simulations are necessary in order to optimize metal forming operations. We present a geometrically nonlinear material model which reproduces the main features of the PLC effect. The material parameters were identified based on experimental data from tensile tests. Special emphasis was put on the critical strain for the onset of PLC effect, ε c , and the statistical characteristics of the stress drop distribution. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Keywords:
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号