Résumé
This paper presents a new method to compute the piezoelastic properties of multidomain single crystals from their single domain state. Based on a quasistatic assumption, a PMN-xPT multidomain is defined as a periodic medium with a lattice composed of layers of two domains in a twin structure. This latter is assumed to have charged domain walls that imply adapted lattice media and boundary conditions. A numerical computation has been performed for a PMN-33PT single crystal. The effective elastic, piezoelectric and dielectric constants of the macroscopic structure are quantified, calculations of the degree of anisotropy and of the wave velocities in different domain pattern configurations are reported.