J. Phys. IV France 112 (2003) 651
DOI: 10.1051/jp4:2003967

Concentration, temperature and deformation dependences of martensite lattice parameters in binary Ti-Ni shape memory alloys

S.D. Prokoshkin¹, V. Brailovski², S. Turenne³, I.Yu Khmelevskaya¹, A.V. Korotitskiy¹ and I.B. Trubitsyna<sup>1

1</sup>  Moscow Steel and Alloys Institute, Laboratory of Thermomechanical Treatment, Leninskiy Prosp. 4, Moscow 119049, Russia
²  École de Technologie Supérieure, Département de Génie Mécanique, rue Notre-Dame Ouest 1100, Montréal, Québec H3C 1K3, Canada
³  École Polytechnique de Montréal, P.O. Box 6079, Station Centre Ville, Montréal, Québec H3C 3AC, Canada

Abstract
X-ray diffractometric study of Ti-47.0 te 50.7 at. % Ni alloys has been performed. A concentration dependence of B19 ' Martensite Lattice Parameters (MLP) exists in the range from 50.0 to 50.7 % Ni. MLP in Ti-47.0 and 50.0 % Ni coincide. Temperature dependence of MLP exists; MLP change in Ti-50.0%Ni alloy is enhanced in the B19 ' to B2 transformation range. In the Ti-50.0% Ni, MLP are different for the quenched martensite and for the one formed from the austenite containing well-developed dislocation substructure. In Ti-50.0% Ni alloy, MLP do not change after its deformation up to 25% strain. Changes in MLP in the case of hyper-equiatomic nickel concentration or due to the presence of highly-dislocated initial austenite are independent of the presence of the R phase during martensite formation.

© EDP Sciences 2003