A comparative study of kinematic hardening rules at finite deformations |
| |
Authors: | Ch Tsakmakis A Willuweit |
| |
Institution: | Institut fur Mechanik, Technische Universität Darmstadt, Hochschulstr. 1, 64289 Darmstadt, Germany |
| |
Abstract: | Kinematic hardening models describe a specific kind of plastic anisotropy which evolves with the deformation process. It is well known that the extension of constitutive relations from small to finite deformations is not unique. This applies also to well-established kinematic hardening rules like that of Armstrong-Frederick or Chaboche. However, the second law of thermodynamics offers some possibilities for generalizing constitutive equations so that this ambiguity may, in some extent, be moderated. The present paper is concerned with three possible extensions, from small to finite deformations, of the Armstrong-Frederick rule, which are derived as sufficient conditions for the validity of the second law. All three models rely upon the multiplicative decomposition of the deformation gradient tensor into elastic and plastic parts and make use of a yield function expressed in terms of the so-called Mandel stress tensor. In conformity with this approach, the back-stress tensor is defined to be of Mandel stress type as well. In order to compare the properties of the three models, predicted responses for processes with homogeneous and inhomogeneous deformations are discussed. To this end, the models are implemented in a finite element code (ABAQUS). |
| |
Keywords: | Plasticity Finite deformations Nonlinear kinematic hardening |
本文献已被 ScienceDirect 等数据库收录! |
|