MISFIT DISLOCATIONS ARRANGED IN A HEXAGONAL NETWORK IN ANISOTROPIC ELASTICITY - RELATED DISPLACEMENT FIELD AND STORED ELASTIC ENERGY

A method presented in a previous paper to determine any biperiodic ela stic displacement field (Bonnet, 1981) is developed analytically for a hexagonal network of misfit dislocations lying along a plane separati ng two different anisotropic crystals. The network is possibly non-reg ular. The three components of the displacement field are expressed, in both the crystals, as double Fourier series. Each harmonic term depen ds on coefficients calculated from the roots of a sextic polynomial wh ose coefficients generalize those established by Eshelby et al. (1953) . For the particular case of a regular hexagonal network, analytical e xpressions are obtained for the stored elastic energy E(S) when (i) th e Burgers vectors are parallel to the interface and (ii) each crystal has an elastic symmetry axis perpendicular to the interface. Applicati ons to low angle twist boundaries parallel to (111) planes in fc.c. ma terials (Al, Cu) and the heterotwin (111)Si parallel-to (111)CoSi2 int erface show in fact small effects of the anisotropy of these crystals on the values of E(S).