2014 The use of the Hall-Petch relation in texture simulations with the Taylor-Bishop-Hill model is proposed as a mean to take into account grain shape effect. The results are compared with those obtained with the usual and relaxed constraint Taylor model for a simple texture and the consequences for the anisotropy coefficient are investigated. J. Physique Lett. 46 (1985) L-1109 L-1113 1 er DEC...

The partial dislocation model for the deformation mechanism of nanocrystalline materials is extended to consider the influence of non-uniform dislocation extension. The non-uniform partial dislocation extension model is more consistent with experimental data than the original partial dislocation model. Additionally, the flow stress obtained from the non-uniform extension model is compared with ...

The fracture of polycrystalline graphene is explored by performing molecular dynamics simulations with realistic finite-grain-size models, emphasizing the role of grain boundary ends and junctions. The simulations reveal a ~50% or more strength reduction due to the presence of the network of boundaries between polygonal grains, with cracks preferentially starting at the junctions. With a larger...

The main focus of the paper is an extension of the classical Taylor theory of plasticity to include the microscopic conditions for slip transfer at grain boundaries. It is demonstrated that such leads to consideration of the grain boundary character distribution function, in concert with the usual local state distribution function. The primary result is an expression for the generalized Taylor ...

We have conducted highP-Tsynchrotron X-ray and time-of-flight neutron diffraction experiments as well as indentation measurements to study equation of state, constitutive properties, and hardness of nanocrystalline and bulk nickel. Our lattice volume-pressure data present a clear evidence of elastic softening in nanocrystalline Ni as compared with the bulk nickel. We show that the enhanced over...

This work investigates the mechanical behavior of nanocrystalline aluminum, with special focus on deformation mechanisms, using molecular dynamics simulations an interatomic potential parameterized by authors. To this end, four samples grain sizes ranging from 8,2 to 14,2 nm were constructed, each a volume 15 x 20 nm3. As expected, data tensile tests at strain rate 1,0 109 s−1 showed inverse Ha...