Superelastic Effect in Polycrystalline Ferrous Alloys
Abstract
In superelastic alloys, large deformation can revert to a memorized shape after removing the stress. However, the stress increases with increasing temperature, which limits the practical use over a wide temperature range. Polycrystalline Fe-Mn-Al-Ni shape memory alloys show a small temperature dependence of the superelastic stress because of a small transformation entropy change brought about by a magnetic contribution to the Gibbs energies. For one alloy composition, the superelastic stress varies by 0.53 megapascal/°C over a temperature range from -196 to 240°C.
- Publication:
-
Science
- Pub Date:
- July 2011
- DOI:
- 10.1126/science.1202232
- Bibcode:
- 2011Sci...333...68O
- Keywords:
-
- MAT SCI