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MiS Preprint
9/1999
Material instabilities in nematic elastomers
Antonio DeSimone and Georg Dolzmann
Abstract
Soft deformation paths and domain patterns in nematic elastomers are analyzed through the minimization of a nonconvex free-energy, recently proposed in the literature. The free-energy density has multiple wells, and is not restricted to small deformations. The problems of calculating the quasiconvex hull of the energy wells and the quasiconvex envelope of the free-energy density are formulated and solved (the latter only in two spatial dimensions). This leads to a complete characterization of the set of soft deformation paths available to a given material, and of its effective macroscopic energy.
