Using our local equilibrium model of the martensitic transformation [ the elastic energy contributions, as the function of martensite volume fraction, ξ, in the phase transformation of single crystalline Cu-11.5wt%Al-5.0wt%Ni shape memory alloy were calculated from our measurements published earlier [. The derivative of the elastic energy δE/δξ=e (E is the total elastic energy stored/released during the austenite to martensite (AM) as well as MA transformation) could be calculated only irrespectively of the ST0 term (T0 is the equilibrium transformation temperature and S is the entropy change of phase transformation). But, since ST0 is independent of ξ, the functions obtained reflect the ξ dependence of e as well as E quantities. From the DSC curves measured at zero uniaxial stress (σ = 0) [, the ξ-T hysteric loop was constructed. Then the e (ξ) curves at fix σ as well as fix T were calculated. The E values obtained from the integral of e (ξ), fit well to the E(σ) as well as E(T) curves calculated from the strain-temperature and stress-temperature curves measured in [.
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