J. Phys. IV France 11 (2001) Pr5-317-Pr5-324
From the lattice measurements of the austenite and the martensite cells to the macroscopic mechanical behavior of shape memory alloysC. Lexcellent1, A. Vivet1, 2, C. Bouvet1, P. Blanc1, C. Satto3 and D. Schryvers3
1 LMARC, UMR 6604 du CNRS, IMFC FR 0067, Université de Franche-Comté, 24 rue de l'Épitaphe, 25000 Besançon, France
2 LURSA, IUT d'Alençon, Université de Caen Basse-Normandie, 61250 Damigny, France
3 Electron Microscopy for Materials Research (EMAT), University of Antwerp RUCA, Groenenborgerlaan 771, 2020 Antwerp, Belgium
On one hand, the lattice measurements of the austenite and the martensite cells for one CuZnAl and one CuAlBe alloys permit to determine the nature of the phase transformation i.e. an "exact" interface between the parent phase and an untwinned martensite variant. Hence, for single crystals, the yield surface looks like a polygon with several sectors. Each sector is defined by its peculiar activated variant. On the other hand, a "micro-macro" integration allows to predict the yield curve for biaxial proportional mechanical tests on polycrystals. This homogenisation process is in agreement with the prediction of a phenomenological approach at the macroscopic scale and fits well the yield experimental points.
© EDP Sciences 2001