Spherically-symmetric solutions for a spherical shell in finite pseudo-elasticity

In a recent paper the authors have incorporated the notion of discontinuous internal variables into the theory of finite elasticity in order to model certain coexistence of phases phenomena encountered in the deformation of s olids. For example, phase changes in polymeric solids may be associated wit h changes in material properties induced by damage, in which case the inter nal variables are interpreted as damage variables. In the present paper the inflation of a thick-walled spherical shell of incompressible isotropic el astic material with a single internal variable is examined on the basis of this theory. The development of two-phase solutions is demonstrated for the loading process, and, for unloading, an example in which a residual deform ation remains after removal of the pressure is given and the corresponding residual stress is calculated. (C) Elsevier, Paris.