On the stability of the martensitic phases in Cu-Zn-Al, and its relationship with the equilibrium phases

P. ARNEODO LAROCHETTE; A.M. CONDÓ; J.L. PELEGRINA; M. AHLERS

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

ELSEVIER SCIENCE SA

Año: 2006 vol. 438 p. 747 - 750

0921-5093

The relative stability of the martensitic phases in Cu-Zn-Al shape memory alloys was used to evaluate the high-temperature equilibrium between the face-centered cubic and disordered hexagonal phases in a set of binary Hume-Rothery compounds. The equilibrium was found to be around an electron concentration of 1.44 in agreement with the available experimental binary phase diagrams. In the calculation, the contribution arising from the distortion of the martensitic structure due to long-range order was considered. It was additionally rationalized that, although the 18R phase is a common martensitic structure, it is not observed in the disordered state.