Martensitic Transformations in B2 Cubic Alloys
Abstract
Many modern shape-memory materials are based on the ordered bcc structure, in particular the B2 structure. These structures may be subjected to a shearing motion to which the material has little resistance. Plausibly, this "Zener instability" can provide the means for these structures to undergo a martensitic phase transition, where the actual distances the atoms move are small enough that exact reversibility (shape-memory) is possible. There are many B2 structures but only some of them exhibit martensitic phase transitions. Some are equi-atomic, highly ordered alloys and some are off-stoichiometry that must be quenched to retain a non-equilibrium B2 structure. We have made thermal, transport, mechanical, Fermi surface topology, and elastic measurements on several B2 martensitic alloys and present our findings in terms of the differences between varios B2 alloys and other structures.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2003
- Bibcode:
- 2003APS..MARS16012L