Les intermétalliques : des superalliages aux quasicristaux
J. Phys. IV France 06 (1996) C2-65-C2-70
A Unique Framework to Describe Short Range Order and Properties of the Ordered State in AlloysD. Le Bolloc'h1, 2, R. Caudron1, 2, E. Cabet1, M. Barrachin1, 2 and A. Finel1
1 Direction des Matériaux, ONERA, 92322 Châtillon sous Bagneux, France
2 Laboratoire Léon Brillouin, CEA/CNRS, 91191 Gif sur Yvette cedex, France
Elastic diffuse scattering of neutrons was performed in situ on two different alloys, Ni3V and Pt3V. Effective pair interactions of an Ising model were deduced from the measured short-range order parameters in the disordered phase. For this two examples, we obtain potentials that don't depend on temperature. Thus we can predict properties of the ordered state. In Ni3V, we describe correctly the temperature variation of the dissociation width of superdislocations and we compare the stability of different phases, L12 and DO22. In the case of Pt3V, we will show how we can relate the measured interactions with the existence of long period structures in the ordered state.
© EDP Sciences 1996