An elasto-plastic damage-coupled mesoscopic model for cold-drawn eutectoid steels

Abstract

The excellent mechanical properties of cold-drawn eutectoid steel wires are related to the particular characteristics of their pearlitic microstructure. The anisotropy arising from the microstructural evolution of pearlite under directional deformation together with the different strengthening mechanisms acting on it, make modelling its behaviour a challenge. Existing models do not reach a compromise between a good description of the microstructural features and their applicability to scales larger than the microscopic level. On the other hand, the effect of damage on the mechanical behaviour can be modelled by applying Continuum Damage Mechanics. In this work, a microstructure-based elastoplastic damage-coupled model is proposed in order to account for the special features of the pearlitic microstructure in terms of damage accumulation, mechanical behaviour and microstructural evolution. The model has been implemented in ABAQUS through user subroutines and its performance has been evaluated by uniaxial tensile test simulations on a Representative Volume Element. The resulting stress-strain curve is in good agreement with experimental data from a 13-pass drawing series, yielding a very similar hardening rate. In addition, when coupling the effect of damage, the softening effect on the mechanical response is captured.