Predicting Dislocation Climb and Creep from Explicit Atomistic Details

Predicting dislocation climb and creep from explicit atomistic details.

Here we report kinetic Monte Carlo simulations of dislocation climb in heavily deformed, body-centered cubic iron comprising a supersaturation of vacancies. This approach explicitly incorporates the effect of nonlinear vacancy-dislocation interaction on vacancy migration barriers as determined from atomistic calculations, and enables observations of diffusivity and climb over time scales and te...

Predicting dislocation climb: Classical modeling versus atomistic simulations

Dislocation climb models from atomistic scheme to dislocation dynamics

We develop a mesoscopic dislocation dynamics model for vacancy-assisted dislocation climb by upscalings from a stochastic model on the atomistic scale. Our models incorporate microscopic mechanisms of (i) bulk diffusion of vacancies, (ii) vacancy exchange dynamics between bulk and dislocation core, (iii) vacancy pipe diffusion along the dislocation core, and (iv) vacancy attachment-detachment k...

Dislocation Creep: Climb and Glide in the Lattice Continuum

A continuum theory for high temperature creep of polycrystalline solids is developed. It includes the relevant deformation mechanisms for diffusional and dislocation creep: elasticity with eigenstrains resulting from vacancy diffusion, dislocation climb and glide, and the lattice growth/loss at the boundaries enabled by diffusion. All the deformation mechanisms are described with respect to the...

Dislocation Climb in the Electron Wind

When a current flows in a conductor, the electron wind can cause atoms to diffuse. This paper considers the consequences of such diffusion along dislocation cores. A dislocation climbing in a crystal is viewed as a non-equilibrium thermodynamic system to define the force that drives self-diffusion along the core. Not only is a dislocation a mass-transport pipe, it also climbs and generates more...