Realistic hardening-to-softening transition effects of metals over the finite strain range up to failure

Abstract

Purpose

A new approach is proposed toward accurately matching any given realistic hardening and softening data from uniaxial tensile test up to failure and moreover, toward bypassing usual tedious implicit trial-and-error iterative procedures in identifying numerous unknown parameters.

Design/methodology/approach

Finite strain response features of metals with realistic hardening-to-softening transition effects up to eventual failure are studied for the first time based on the self-consistent elastoplastic J₂-flow model with the logarithmic stress rate. As contrasted with usual approximate and incomplete treatments merely considering certain particular types of hardening effects such as power type hardening, here a novel and explicit approach is proposed to obtain a complete form of the plastic-work-dependent yield strength over the whole hardening and softening range.

Findings

A new multi-axial evolution equation for both hardening and softening effects is established in an explicit form. Complete results for the purpose of model validation and prediction are presented for the finite strain responses of monotonic uniaxial stretching up to failure.

Originality/value

New finite strain elastoplastic equations are established with a new history-dependent variable equivalently in place of the usual plastic work. With these equations, a unified and accurate simulation of both gardening and softening effects up to failure is achieved for the first time in an explicit sense without involving usual tedious implicit trial-and-error iterative procedures.

Citation

Xu, Z.-H., Zhan, L., Wang, S.-Y., Xi, H.-F. and Xiao, H. (2021), "Realistic hardening-to-softening transition effects of metals over the finite strain range up to failure", Multidiscipline Modeling in Materials and Structures, Vol. 17 No. 3, pp. 525-536. https://doi.org/10.1108/MMMS-05-2020-0099