Modeling work hardening of pearlitic steels by phenomenological and Taylor-type micromechanical models

The prediction of the work-hardening behavior of fully lamellar pearlitic steels during cold deformation is attempted by means of phenomenological and Taylor-type micromechanical models. The phenomenological model is based on the Bouaziz model and reformulated with the iso-strain rule of mixture. It is found that the simple power law of interlamellar spacing evolution overestimates the decrease of interlamellar spacing., but this overestimation is compensated by an underestimation due to the dislocation propagation mechanism implied by the phenomenological model and that may be the reason that this model leads to a reasonable prediction of the work hardening. The full constraint Taylor pearlite model calculates yield stress of the ferrite phase. The cementite behavior is also considered in the current paper. A tentative transient law between the dislocation propagation and multiplication mechanisms is proposed and a very good prediction of work hardening is found for both wiredrawing and rolling. (c) 2005 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.