Indentation is a new method for estimating residual stress. The plastic behavior of the materials under study can affect indentation parameters and, thus, influences the results of residual stress measurement. In this paper, the effect of yield stress and work-hardening exponent on the accuracy of residual stress measurements in steels and aluminums was studied. Results showed that, for m...

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...

Abstract: In the current work, the strain hardening behavior of dual-phase steels with different silicon content (0.34- 2.26 Wt. %) was examined using the modified Crussard-Jaoul analysis. It was shown that these dual-phase steels deform in two stages over a uniform strain range. Each stage exhibited a different strain hardening exponent varying with silicon content. At the first stage, work...

The material properties of OFHC copper film was investigated with the High-Speed Material Micro Testing Machine (HSMMTM) at the high strain rates. The rate-dependent stress-strain curves from the experiment and the Johnson−Cook curve fitting showed large discrepancies as the plastic strain increases since the constitutive model implies no rate-dependent strain hardening effect. A new constituti...

1967 Price 8s 6d net .-summary The time hardening, life fraction and strain hardening hypotheses variously proposed to describe tiniaxisl creep deformation are considered and compared with experimental evidence. It is concluded that the strain hardening hypothesis is the most nearly correct, the experimental strains usually being within 50% of those predicted. Further, rheological and modified ...

In this paper the effect of different hardening models in simulating the U-bending process for AA5754-O and DP-Steel, taking a benchmark of NUMISHEET 93 2-D draw bending, has been discussed. The hardening models considered in simulations are: isotropic hardening, pure (linear) kinematic hardening and combined (nonlinear kinematic) hardening. The influence of hardening models on predicting sprin...

-Dislocation theory is used to invoke a strain gradient theory of rate independent plasticity. Hardening is assumed to result from the accumulation of both randomly stored and geometrically necessary dislocations. The density of the geometrically necessary dislocations scales with the gradient of plastic strain. A deformation theory of plasticity is introduced to represent in a phenomenological...

Using molecular dynamics simulations of a generic model, we observe strain hardening in highly cross-linked polymer glasses under tensile deformation. We show that formation of microvoids, without bond breaking, constitutes the microscopic origins of strain hardening. A well-defined functional form is observed for the void size distribution that is consistent with voids in dense equilibrium Len...

The present study considers an elastic-plastic contact analysis during loading-unloading of a deformable sphere with a rigid flat using finite element method. The effect of strain hardening on the contact behavior of a nonadhesive frictionless elastic-plastic contact is analyzed using commercial finite element software ANSYS. To study the strain hardening effect different values of tangent modu...

This study deals with the relation between the microstructure of semi-crystalline polymers and their intrinsic deformation and fracture behaviour. For this purpose, the deformation and failure of well-characterised PET, PE and PP samples have been investigated thoroughly. Compression tests on amorphous and cold crystallised PET showed that the strain hardening remained unchanged, despite the de...