Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7883299 | Acta Materialia | 2012 | 8 Pages |
Abstract
The magnetic contribution to the martensitic transformation entropy change plays a crucial role in the transition properties of metamagnetic shape memory alloys. This contribution leads to a common dependence of the total entropy change at the structural transformation, ÎStr, on the normalized temperature difference δAtr=(TCA-Ttr)/TCA (where TCA is the Curie temperature of the austenitic phase and Ttr is the transformation temperature) whose main feature is a decrease in ÎStr with increasing δAtr. A phenomenological model based on a Bragg-Williams approximation has been proposed to describe the observed behaviour in terms of the evolution of the magnetic contribution to the total entropy change. The proposed approximation provides a good fitting between predicted and experimental entropy changes obtained for different Ni-Mn-based alloy systems.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
V. Recarte, J.I. Pérez-Landazábal, V. Sánchez-Alarcos, V. Zablotskii, E. Cesari, S. Kustov,