Thermodynamics of Ideal Pseudoelasticity

Experimental results are shown for CuZnAl single crystals which summarize the thermal equation of state of these alloys in the pseudoelastic temperature range, i.e. their (P,d,T)- behaviour. For a partial explanation the first and second law of thermodynamics are applied under the assumption that the essential relevant constitutive ingredients are i.) a non-convex free energy ii.) a coherency energy between the austenitic and martensitic regions. The theory predicts an unstable phase equilibrium and allows the calculation of the heat emitted during the transition. It also determines which part of the heat is reversibly emitted and which irreversibly