It is well known that damage evolution models requires a length to avoid spurious localization. We gather these type of models under the name “non-local damage models”. In fact, non-locality is strictly needed only when the stress-strain curve starts to have a negative slope. Before this point, local models may be used. For instance, when damage exhibits some hardening, the stress-strain curve ...

The objective of this study is to evaluate the effect of constitutive equations on the prediction accuracy for springback in cold stamping with various deformation modes. In this study, two types of yield functions—Hill’48 and Yld2000-2d—were considered to describe yield behavior. Isotropic and kinematic hardening models based on the Yoshida–Uemori model were also adopted to describe hardening ...

In carrying out engineering calculations the dimensions of the investigated models are often neglected. On the one hand, it can greatly simplify the calculation of the plane model, but on the other hand, exclude the consideration of the effect of the sample geometric dimensions on the process under study. In the study of strike systems, which are based on wave processes, we should not exclude t...

Metallic nanowires usually exhibit ultrahigh strength but low tensile ductility owing to their limited strain hardening capability. Here we study the unique strain hardening behavior of the five-fold twinned Ag nanowires by nanomechanical testing and atomistic modeling. In situ tensile tests within a scanning electron microscope revealed strong strain hardening behavior of the five-fold twinned...

Hardening plasticity has a long history in constitutive modelling, with many applications in geomechanics. Mathematical models of non-hardening plasticity involve the definition of a single stationary yield surface in stress-space. Examples include the conventional models of elasto-plasticity, often based on the yield criteria of Tresca, von Mises, and Mohr-Coulomb. Within the yield surface the...

The finite element (FE) method may suffer from numerical instability and mesh dependency when modelling the formation of shear bands using strain-softening constitutive models. Nonlocal methods have been shown to be capable avoiding these issues effectively. This paper proposes a novel generic algorithm for incorporating existing nonlocal into FE formulation elasto-plastic models with volumetri...

We prove the wellposedness, with respect to the maximum norm, of stress-strain laws of nonlinear kinematic hardening type, in particular of the Chaboche model.

The digital image correlation (DIC) technique was utilized in conjunction with mechanical experiments carried out at different strain rates to study the negative strain rate sensitivity (NSRS) in face-centered cubic (fcc) Hadfield steels. The results shed light onto the variation of local strain fields and serrations in the stress– strain curves of Hadfield steels as a function of strain rate w...