DISLOCATION THEORY-BASED CONSTITUTIVE MODELING - FOUNDATIONS AND APPLICATIONS

This paper deals with a unified elastic-viscoplastic constitutive mode l based on dislocation density considerations. A combination of a kine tic equation, which describes the mechanical response of a material at a given microstructure in terms of dislocation glide, and evolution e quations for internal variables characterising the microstructure prov ide the constitutive equations of the model. The internal variables ar e associated with the densities of dislocations of various kinds (or t he total dislocation density in the simplest version of the model). Th e model has a modular structure and can be adjusted to describe a part icular type of forming process. Dynamic recovery, dynamic recrystallis ation and dynamic strain ageing are included. Implementation of the mo del in the ABAQUS code has shown its versatility and good predictive c apability. Examples of use of the model are given. (C) 1998 Elsevier S cience S.A. All rights reserved.