J. Phys. IV France 01 (1991) C4-217-C4-222
EFFECT OF THERMAL CYCLING ON THE MARTENSITIC TRANSFORMATION OF βCu-Zn-Al CONTAINING γ PRECIPITATESJ. PONS1, F.C. LOVEY2 and E. CESARI1
1 Dept. de Fisica, Universitat de les Illes Balears, Ctra de Valldemossa, Km. 7.5 E-07071 Palma de Mallorca, Spain
2 Division Metales, Centro Atomico Bariloche, 8400 S. C. de Bariloche, Argentina
We present a calorimetric and TEM study of the thermal cycling effects on the martensitic transformation in [MATH] Cu-Zn-Al single crystals containing different distributions of [MATH]-phase precipitates. The calorimetric results show a high reproducibility of the transformation during cycling (up to 200 cycles) for dense distributions of coherent precipitates, and a shift towards higher temperatures (mainly the direct transformation) for a distribution of precipitates of bigger size. Arrays of dislocations similar to those formed in precipitate-free specimens were observed in this study, although in a small quantity. Moreover, complex dislocation networks in the matrix surrounding the precipitates were also observed. The effects of both kinds of dislocation arrays on the martensitic transformation are discussed.
© EDP Sciences 1991