One-dimensional pseudoelastic theory of shape memory alloys

The one-dimensional isothermal pseudoelastic theory of shape memory alloys which the present authors proposed has been further exploited in order to clarify the thermodynamic meaning of the interaction energy introduced in the theory. From the equilibrium condition of the two-phase state, it is shown that the partial derivative of the interaction energy with respect to the phase fraction represents the thermodynamic driving force of the phase transformation. Functions for the interaction energy are derived from the definition of the driving force of the phase transformation in equilibrium. Analytical results predicted by the present theory agree well qualitatively with available experimental observations. Tanaka's transformation kinetics are also well modelled by the present theory.