Material symmetry in deformed configurations

Abstract This paper is concerned with the symmetry groups of elastic materials in deformed configurations. It is shown how to identify the symmetry groups of materials (when the constitutive equation is given) even if these materials are not in undistorted configurations. As an example in Section 3 the isotropic case is studied. In Section 4 is studied the case of a linear convected stress for an isotropic material and Section 5 is devoted to solve the following problem: when a transversaly isotropic material is in fact an isotropic one but in a deformed configuration?