Bounding surface plasticity model with extended Masing behavior

Abstract

In this paper, a deviatoric bounding surface plasticity model that preserves Masing's rule and an algorithm that allows for the lack (or existence) of elastic range is formulated. This model inherits the advantages of multilayer models like Mroz's and the simplicity and continuity of the bounding surface plasticity. The material-specific parameters can be obtained directly and automatically from the experimental non-linear stress–strain “backbone” curves. A mapping converts monotonic isotropic hardening functions into anisotropic ones that depend on the previous load history. The cyclic behavior resembles that of the nested yield surface models, the cycles are stabilized from the first loop, the unloading curve preserves a fixed homological ratio (of two) with the initial monotonic one and the process reloads through previous hardening functions when the corresponding stress–strain curves are intersected. Furthermore, it also maintains the advantages of bounding surface models, like the possibility of using a continuous non-linear hardening function that depends solely on stresses and that is interpolated through only two surfaces. Although the formulation in this paper is based on the von Mises criterion, different criteria could be used.