Calculus of Variations and Geometric Measure Theory

M. Friedrich - L. Kreutz - B. Schmidt

Emergence of rigid Polycrystals from atomistic Systems with Heitmann-Radin sticky disk energy

created by kreutz on 02 Jun 2020
modified on 04 Feb 2021


Accepted Paper

Inserted: 2 jun 2020
Last Updated: 4 feb 2021

Journal: Archive for Rational Mechanics and Analysis
Pages: 58
Year: 2020

ArXiv: 2006.01558 PDF


We investigate the emergence of rigid polycrystalline structures from atomistic particle systems. The atomic interaction is governed by a suitably normalized pair interaction energy, where the `sticky disk' interaction potential models the atoms as hard spheres that interact when they are tangential. The discrete energy is frame invariant and no underlying reference lattice on the atomistic configurations is assumed. By means of $\Gamma$-convergence, we characterize the asymptotic behavior of configurations with finite surface energy scaling in the infinite particle limit. The effective continuum theory is described in terms of a piecewise constant field delineating the local orientation and micro-translation of the configuration. The limiting energy is local and concentrated on the grain boundaries, i.e., on the boundaries of the zones where the underlying microscopic configuration has constant parameters. The corresponding surface energy density depends on the relative orientation of the two grains, their microscopic translation misfit, and the normal to the interface. We further provide a fine analysis of the surface energies at grain boundaries both for vacuum-solid and solid-solid phase transitions.