RheoMan: a five-year, ERC-funded (Advanced Grant), project to model the rheology of the Earth's mantle

Nov 5, 2015 Disclination modeling of grain boundaries Results

A new publication by X. Sun et al. on continuous description of the atomic structure of grain boundaries was just on line in International Journal of Plasticity.

In this paper, we develop an atomistic-to-continuum method to derive dislocation, generalized-disclination density fields and the associated elastic strain, rotation, curvature and second-distortion fields from the atomic structure of grain boundaries. The method is applied to a copper symmetrical tilt boundary as obtained from molecular dynamics simulations.

 

The core structure of the boundary is found to contain edge dislocations and dipoles of generalized-disclinations, including standard wedge-disclination dipoles. The latter reflect in particular localized shear and stretch discontinuities across the interface, in addition to the overall rotation discontinuity.

 

For more details,

X. Sun, V. Taupin, C. Fressengeas and P. Cordier, Continuous description of the atomic structure of grain boundaries using dislocation and generalized-disclination density fields, International Journal of Plasticity (2015), doi: 10.1016/j.ijplas.2015.10.003