DocumentCode :
3602553
Title :
Magnetic-Field-Induced Isothermal Entropy Change Across the Magnetostructural Transition in Ni–Mn–Ga Melt-Spun Ribbons
Author :
Zongbin Li ; Sanchez-Valdes, C.F. ; Sanchez Llamazares, J.L. ; Yudong Zhang ; Esling, Claude ; Xiang Zhao ; Liang Zuo
Author_Institution :
Key Lab. for Anisotropy & Texture of Mater., Northeastern Univ., Shenyang, China
Volume :
51
Issue :
11
fYear :
2015
Firstpage :
1
Lastpage :
4
Abstract :
The phase transformation and the magnetocaloric effect of Ni53Mn22Ga25 and Ni52Mn26Ga22 ribbons were studied. It is shown that in melt-spun Ni53Mn22Ga25 ribbons the magnetic transition and the martensitic transformation are well separated. For this sample, the austenite grains are columnar in shape with a typical preferential orientation of {001}A//ribbon plane. For a magnetic field change of 5 T, the maximum entropy change ΔSTmax of -4.7 Jkg-1K-1 is achieved at the vicinity of the martensitic transformation. For the Ni52Mn26Ga22 ribbons, the structural transformation and the magnetic transition occurred simultaneously in both melt-spun and annealed ribbons. Owing to the coupled magnetostructural transformation, a ΔSTmax of -11.4 Jkg-1K-1 is reached for a magnetic field change of 5 T in melt-spun Ni52Mn26Ga22 ribbons. After thermal annealing, ΔSTmax increases to -30.0 Jkg-1K-1, which is almost three times higher as that of the initial melt-spun ribbons, due to the improved atomic ordering and the coupling of the intermartensitic transformation with the magnetostructural transformation.
Keywords :
annealing; entropy; gallium alloys; magnetic transition temperature; magnetocaloric effects; manganese alloys; martensitic transformations; melt spinning; nickel alloys; Ni52Mn26Ga22; Ni53Mn22Ga25; annealed ribbons; atomic ordering; austenite grains; coupled magnetostructural transformation; intermartensitic transformation; magnetic field change; magnetic flux density 5 T; magnetic-field-induced isothermal entropy change; magnetocaloric effect; martensitic transformation; maximum entropy change; melt-spun ribbons; phase transformation; preferential orientation; thermal annealing; {001}A//ribbon plane; Annealing; Entropy; Magnetic separation; Metals; Perpendicular magnetic anisotropy; Magnetocaloric effect; Magnetocaloric effect (MCE); Magnetostructural transformation; Melt-spun ribbons; Ni-Mn-Ga alloys; Ni???Mn???nGa alloys; magnetostructural transformation; melt-spun ribbons;
fLanguage :
English
Journal_Title :
Magnetics, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9464
Type :
jour
DOI :
10.1109/TMAG.2015.2438023
Filename :
7113859
Link To Document :
بازگشت