Mechanical properties of (Ni, Fe)Cr2O4 polycrystal spinels studied by molecular dynamics simulations.

The elastic moduli and mechanical properties at the onset of crack in nanocrystalline and nanoporous (Ni, Fe)Cr2O4 compounds with a spinel structure are investigated by molecular dynamics simulations. The polycrystalline structures generated contain nanograins from 2.5 to 30 nm in diameter.

Mechanical behavior of (Ni, Fe)CrO spinel grain boundaries studied by molecular dynamics simulations.

Using molecular dynamics simulations, we study the fracture initiation of grain boundaries in NiCrO and FeCrO of spinel structure. These compounds are representative of corrosion layers of nickel-chromium-iron austenitic stainless alloys. Uniaxial deformation is applied to several symmetric tilt-, twist-, and random-grain boundaries until complete decohesion is reached, in order to measure the critical cleavage stresses.

Disordering and grain boundaries of (Ni,Fe)Cr2O4 spinels from atomistic calculations.

A novel empirical potential has been developed to evaluate the thermodynamic stability of Ni(1-x)Fe(x)Cr2O4 spinels. The simulations confirm the hypothesis that the NiCr2O4-FeCr2O4 pseudo-binary has normal structure spinel up to 1000 K and stabilizes as a solid solution. However, the disordering energy (normal to inverse spinel) is found higher for FeCr2O4 than for NiCr2O4 spinel.