Outstanding role of the magnetic entropy in arrested austenite in an ordered Ni45Mn36.7In13.3Co5 metamagnetic shape memory alloy

SCRIPTA MATERIALIA

卷:168

Article

Perez-Landazabal, J. I.^1,2  Recarte, V.^1,2  Sanchez-Alarcos, V.^1,2  Ruiz, M. Jimenez³  Cesari, E.⁴ 

[1] Univ Publ Navarra, Dept Ciencias, Campus Arrosadia, Pamplona 31006, Spain

[2] Univ Publ Navarra, Inst Adv Mat INAMAT, Campus Arrosadia, Pamplona 31006, Spain

[3] Inst Laue Langevin, 71 Ave Martyrs,CS 20156, F-38042 Grenoble 9, France

[4] Univ Illes Balears, Dept Fis, Ctra Valldemossa,Km 7-5, E-07122 Palma De Mallorca, Spain

关键词: Ferromagnetic shape memory alloys;    Martensitic phase transformation;    Thermodynamics;    Magnetic entropy;   

DOI  :  10.1016/j.scriptamat.2019.04.035

来源: Elsevier

【 摘 要 】

The relevance of the entropy and in particular the outstanding role of the magnetic contribution is analyzed in a non-equilibrium arrested austenite phase in a Ni45Mn36.7In13.3Co5 metamagnetic shape memory alloy. The Debye and Bragg-Williams approximations have been used to analyze and quantify the vibrational and magnetic contributions respectively, to the total entropy change linked to the martensitic transformation. The sign on the entropy change associated to the forward austenite to martensite transformation is different depending on whether it occurs at low or at high temperature as a consequence of the different vibrational and magnetic contributions. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

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