Electronic Structure and Martensitic Transformation in a ZrRh Alloy

Institute of Metal Physics, Nat. Acad. Sc. Ukr., Vernadsky St. 36, 252142 Kiev, Ukraine

Abstract

Experiments have revealed that equiatomic ZrRh alloy exhibits, upon cooling or heating, a structural transformation of the martensitic type from B2 to B19’ and vice versa, involving a hysteresis of the order 200°C and a shape memory effect. On the basis of the electronic structure calculation for the B2 phase of the ZrRh alloy, it is suggested that a reason for the structural instability of this ZrRh phase possessing a high-symmetry can be presence of a flat region near the Fermi level in the dispersion law.