On thermodynamics and intrinsically equilibrated materials

Summary The existence and uniqueness of free energy functions is demonstrated for a class of materials broad enough to contain as special cases those of the theory of finite elasticity, the theory of hypo-elasticity, and the theory of internal state variables for which the path of evolution is invariant under rescalings of time. Dedicated toDario Graffi on his 70th Birthday Entrata in Redazione il 24 giugno 1975. This research was supported by the U. S. National Science Foundation under Grant GP-32951X2.