J. Phys. IV France 01 (1991) C4-361-C4-366
DETECTION OF THE R-PHASE IN Ni-Ti SHAPE MEMORY ALLOYSK. GOUBAA1, 2, M. MASSE1, 2 and G. BOUQUET1, 2
1 Ecole Nationale Supérieure de Chimie de Paris, 11 rue Pierre et Marie Curie, F-75231 Paris cedex 05, France
2 Centre d'Etudes de Chimie Métallurgie, 15 rue Georges Urbain, F-94407 Vitry sur Seine cedex, France
In NiTi based shape memory alloys, a transient phase, called R-phase, occurs on cooling before the martensitic transformation. The detection of the R-phase seems to be dependent on various parameters and particularly on experimental technique. Indeed, in this study we examine the sensitivity of various methods as internal friction, transmission electron microscopy, X-ray diffraction, electrical resistance, differential scanning calorimetry. However thermal treatments and chemical content are also taken into account.
© EDP Sciences 1991