J. Phys. IV France 01 (1991) C4-283-C5-288
MARTENSITIC TRANSITION ENTROPY CHANGE AND ELASTIC CONSTANTS OF Cu-Al-Be ALLOYSD. RIOS-JARA1, A. PLANES2, Ll. MAÑOSA,2, J. ORTIN2, S. BELKAHLA3, M. MORIN3, G. GUÉNIN3 and J.L. MACQUERON3
1 On leave of absence from : IIM-UNAM, Apdo. Postal 70-360, 04510 Mexico D.F., Mexico.
2 Departament ECM, Universitat de Barcelona, Av. Diagonal 647, SP-08028 Barcelona, Spain
3 GEMPPM-LTSU, INSA, Bât 502, 20 Av. A. Einstein, F-69621 Villeurbanne cedex, France
Measurements of the enthalpy ([MATH]H) and entropy ([MATH]S) changes associated with the martensitic transformation of Cu-Al-Be single crystals of different compositions, were performed by differential scanning calorimetry. In addition, the elastic constants of the body-centered-cubic parent phase single crystals were measured as a function of temperature, using the ultrasonic pulse-echo frequency varying - phase detection method, and the value of the elastic anisotropy (A = C44/C') was computed at the martensitic transformation temperature. The results are in good agreement with a theoretical expression obtained according to models previously proposed, which relates [MATH]S to the elastic anisotropy of the parent phase at the martensitic transformation temperature.
© EDP Sciences 1991