Gradient nano-grained (GNG) metals are a unique class of materials with spatial gradients in grain size, typically from the surface to the bulk. Here the gradient mechanical behavior inGNG copper is studied by a crystal plasticity finite elementmodel that accounts for grainsize-dependent yield strengths. The associated finite element simulations reveal both the gradient stress and gradient plas...

Abstract This paper is concerned with the strain gradient theory of porous thermoelastic solids. We study deformation isotropic chiral cylinders subjected to a temperature field that linear in axial coordinate. It shown solution can be reduced two-dimensional problems. The results are used investigate circular cylinder uniform variation. In contrast case achiral materials, thermal produces tors...

This paper deals with error estimates for space-time discretizations in the context of evolutionary variational inequalities of rate-independent type. After introducing a general abstract evolution problem, we address a fully discrete approximation and provide a priori error estimates. The application of the abstract theory to a semilinear case is detailed. In particular, we provide explicit sp...

Full surface strain measurement requires the determination of two out-of-plane and four in-plane displacement gradient components of the surface strain tensor. Shearography is a full-field speckle interferometry technique with a sensitivity predominately to the out-of-plane displacement gradient. Speckle pattern photography has the sensitivity to the in-plane displacement, and taking the deriva...

Anisotropic strain gradient elasticity theory is applied to the solution of a mode III crack in a functionally graded material. The theory possesses two material characteristic lengths, , and ,8, which describe the size scale effect resulting from the underlining microstructure, and are associated to volumetric and surface strain energy, respectively. The governing differential equation of the ...

Because of their high surface over volume ratio, the mechanical behavior of micrometer sized structures differs from that of usual macroscopic objects. Their surface plays a key role, and this property has been proposed to devise micromechanical sensors of environmental changes [1]. In particular, a significant effort has been put on the development of biological sensors [2], thus highlighting ...

In a remarkable series of experiments, Elssner et al. (1994) and Korn et al. (2002) observed cleavage cracking along a bimaterial interface between Nb and sapphire. The stress required for cleavage cracking is around the theoretical strength of the material. Classical plasticity models fall short to reach such a high stress level. We use the conventional theory of mechanism-based strain gradien...