J. Phys. IV France
Volume 115, June 2004
Page(s) 269 - 278

J. Phys. IV France
115 (2004) 269
DOI: 10.1051/jp4:2004115032

On the R-phase transformation related phenomena in NiTi polycrystals subjected to thermomechanical loads

P. Sittner1, D. Lugovyy2, D. Neov2, M. Landa3, P. Lukas2 and V. Novak1

1  Institute of Physics, ASCR, Na Slovance 2, 18221, Czech Republic
2  Nuclear Physics Institute, ASCR, 25068 Rez, Czech Republic
3  Institute of Thermodynamics, ASCR, Prague 8, 18221, Czech Republic

Results of in-situ neutron diffraction studies of the B2 $\leftrightarrow$R transformation and R-phase reorientation processes in thermal, mechanical and thermomechanical loads on NiTi alloy polycrystals are presented. It is discussed how the crystallographic features and structure instability of R-phase affects the macroscopic thermomechanical $\sigma-\varepsilon-T$ response of NiTi when the R-phase is involved.

© EDP Sciences 2004