An efficient elasto-visco-plastic self-consistent formulation: Application to steel subjected to loading path changes

• Published in: International journal of plasticity Vol. 135; p. 102812
• Main Authors: Jeong, Youngung, Tomé, Carlos N.
• Format: Journal Article
• Language: English
• Published: New York Elsevier Ltd 01.12.2020; Elsevier BV
• Subjects: Austenitic stainless steels; Bauschinger effect; Constitutive equations; Constitutive relationships; Dislocation density; Effective medium model; Elasto-visco-plasticity; Inclusions; Low carbon steels; Modulus of elasticity; Numerical stability; Polycrystals; Strain; Strain-path changes; Elasto-visco-plasticity; Effective medium model; Strain-path changes
• ISSN: 0749-6419; 1879-2154
• DOI: 10.1016/j.ijplas.2020.102812

A novel elasto-visco-plastic self-consistent (EVPSC) formulation based on the scheme of the homogeneous effective medium is presented. The constitutive behavior of a polycrystal is described as that of an elasto-visco-plastic effective medium interacting with grains treated as elasto-visco-plastic ellipsoidal inclusions. The formulation is based on the definition of a unique elasto-visco-plastic compliance, so avoiding the inconsistency arising from assuming superimposed elastic and visco-plastic interaction laws, as made in similar elasto-visco-plastic models. In addition, the elasto-visco-plastic constitutive equation of crystal and aggregate is formulated in terms of stress increments, which leads naturally to a semi implicit solution scheme. The superior numerical stability and computational efficiency of the new incremental EVPSC model (denoted as ΔEVPSC) are demonstrated by applying the model to a 316L austenitic stainless steel and comparing against other elasto-plastic models. The modeling capability for predicting texture, stress-strain response, and Bauschinger effect are demonstrated using a dislocation-density based hardening law applied to low carbon (LC) steel subjected to deformation histories that involve strain-path changes. •A new efficient elasto-visco-plastic self-consistent formulation is developed.•The computational efficiency of the new model is superior to other similar models.•The new model successfully captured flow behavior under complex loading histories.