Va. Chernenko et Va. Lvov, THERMODYNAMICS OF MARTENSITIC TRANSFORMATIONS AFFECTED BY HYDROSTATIC-PRESSURE, Philosophical magazine. A. Physics of condensed matter. Structure, defects and mechanical properties, 73(4), 1996, pp. 999-1008
The martensitic beta(1)-->beta(1)' transformation in Ni2MnGa Heusler a
lloy and B2-->R transformations in two Ti-Ni-Fe alloys have been studi
ed and the latent heats of these transformations measured. The shifts
of martensitic transformation temperatures under the action of applied
hydrostatic pressure have been determined. The experimental data are
analysed on the basis of Landau theory. To achieve this, a proper ferr
oelastic phase transition with two-component and three-component order
parameters is considered. Mathematical expressions relating the press
ure shifts of lability temperatures to the order parameters, softening
elastic moduli and phases volumes are obtained. The volume changes ac
companying the martensitic transformations in Ni2MnGa, Ti0.50Ni0.47Fe0
.03 and Au0.525Cd0.475 are evaluated in three different ways.