Numerical aspects in the finite element simulation of the Portevin–Le Chatelier effect

Serrated yielding and propagation of localized bands of plastic strain rate are the apparent phenomena of the Portevin–Le Chatelier (PLC) effect. The finite element modeling of this effect is investigated, using a model proposed by Zhang et al. [74] describing dynamic strain aging, and material parameters for a Nickel based superalloy at 500 °C. This work presents: (1) an efficient implicit integration scheme of the constitutive equations in the presence of instabilities; (2) a numerical tool to determine the type of plastic strain rate localization bands based on results of simulations; and (3) a mesh and time discretization sensitivity analysis of the model regarding the characteristics of PLC bands. This analysis is carried out in 2D and 3D for axisymmetric smooth and notched specimens.