Inserted: 22 dec 2010
Last Updated: 11 sep 2012
Journal: SIAM J. Math. Anal.
In this paper we rigorously derive a line-tension model for plasticity as the $\Gamma$-limit of a nonlinear mesoscopic dislocation energy, without resorting to the introduction of an ad hoc cut-off radius. The $\Gamma$-limit we obtain as the length of the Burgers vector tends to zero has the same form as the $\Gamma$-limit obtained by starting from a linear, semi-discrete dislocation energy. The nonlinearity, however, creates several mathematical difficulties, which we tackled by proving suitable versions of the Rigidity Estimate in non-simply-connected domains and by performing a rigorous two-scale linearisation of the energy around an equilibrium configuration.
Keywords: $\Gamma$-convergence, nonlinear elasticity, dislocations, plasticity, rigidity estimate