High temperature Ni45Co5Mn25 − xFexGa20Cu5 ferromagnetic shape memory alloys. (June 2017)

• Record Type: Journal Article
• Authors: Pérez-Checa, A.; Feuchtwanger, J.; Musiienko, D.; Sozinov, A.; Barandiaran, J.M.; Ullakko, K.; Chernenko, V.A.
• Is Part Of: Scripta materialia. Number 134(2017)
• Page Start: 119
• Page End: 122
• Publication Date: 2017-06
• Subjects: Ni45Co5Mn25 − xFexGa20Cu5 -- Magnetic shape memory alloys -- Martensitic transformation -- Curie temperature -- Tetragonality ratio; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2017.03.002
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: We anticipated that replacing Mn by Fe in the Ni50 − y Coy Mn25 − x Fex Ga25 − z Cuz magnetic shape memory alloys would increase their Curie temperature and spontaneous magnetization. In particular, in the set of alloys Ni45 Co5 Mn25 − x Fex Ga20 Cu5 (x = 0, …8), a record-breaking combination of high martensitic transformation temperature (400 K) and Curie temperature (458 K ) has been achieved for Ni45 Co5 Mn21 Fe4 Ga20 Cu5 . This alloy shows a non-modulated tetragonal martensite with the lowest lattice distortion ratio, c/a = 1.15, near the reverse martensitic transformation temperature. Because of the high Curie temperature and low c/a ratio, the Ni45 Co5 Mn25 − x Fex Ga20 Cu5 and Ni50 − y Coy Mn25 − x Fex Ga25 − z Cuz alloys are promising candidates for high temperature magnetic shape memory applications. Graphical abstract: