Vibrational Behaviour of Cu-Based BCC Alloys
Departament d'Estructura i Constituents de la Matèria, Facultat de Fίsica, Universitat de Barcelona, Diagonal 647, 08028 Barcelona, Catalonia, Spain
Using experimental data from ultrasonic and neutron scattering measurements for different Cu-based bcc alloys undergoing a martensitic transformation, we show that: (i) the relationship between the elastic constant C’ and the zone boundary frequency ωZB of the associated phonon branch, both evaluated at the transition point TM, conforms to the dependence predicted by a Landau model, recently proposed for martensitic transformations and (ii) the elastic anisotropy A at TM has, within the experimental accuracy, a constant value; this last finding being not explained by the existing models. Some suggestions are envisaged to account for this fact.
© EDP Sciences