A CONSTITUTIVE EQUATION FOR NONLINEAR SOLIDS WHICH UNDERGO DEFORMATION INDUCED MICROSTRUCTURAL CHANGES

Classical theories of elasticity assume that the Cauchy stress in the material depends on the deformation gradient of particles in the current configuration. Such as assumption can usually be motivated by the presence of a single micromechanism. Here we consider the possibility that as the material is deformed an additional micromechanism might come into play and have a role in determining the Cauchy stress. We show that "inelastic" behavior of some materials can be explained within the context of such a theory. To illustrate our ideas, we use the ideas of scission and reforming of networks within the context of polymeric materials. The theory is of course much more general and can be used to describe the mechanics of materials in which microstructural changes are induced due to deformations.