Team Meeting

The modelling of the elastoplastic behaviour of single

crystals with infinite latent hardening leads to a nonconvex energy

density, whose minimization produces fine structures. The computation

of the quasiconvex envelope of the energy density involves the solution

of a global nonconvex optimization problem. Previous work based on a

brute-force global optimization algorithm faced huge numerical

difficulties due to the presence of clusters of local minima around the

global one. We present a different approach which exploits the structure

of the problem both to achieve a fundamental understanding on the

optimal microstructure and, in parallel, to design an efficient

numerical relaxation scheme.

This work has been carried out jointly with Carsten Carstensen

(Humboldt-Universitaet zu Berlin) and Sergio Conti (Universitaet

Duisburg-Essen)