Non-linear Thermoelasticity, Irreversible Thermodynamics and Elastic Instability

1. Introduction. In the linear range a general theory of thermoelasticity based on irreversible thermodynamics was developed and discussed extensively in some earlier work ([3], [4], [9]). It was assumed that the elastic solid is initially in a stress-free equilibrium state at uniform temperature. Completely linearized perturbations in the vicinity of this equilibrium state are then analyzed assuming the strains, the rotations, the displacements and temperature variations to be small of the first order. The case of similar first order perturbations for a solid in equilibrium at uniform temperature but in a state of initial stress was also analyzed in the context of the analogous case of a fluid saturated, porous medium