Open AccessThe magnetocaloric effect of the Gd-based amorphous composite with Gd nanocrystals
Author(s) -
Yongtian Wang,
Zongde Liu,
Jun Yi,
Xue Zhi-Yong
Publication year - 2012
Publication title -
wuli xuebao
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.199
H-Index - 47
ISSN - 1000-3290
DOI - 10.7498/aps.61.056102
Subject(s) - magnetic refrigeration , materials science , composite number , amorphous solid , magnetic force microscope , paramagnetism , amorphous metal , heat capacity , nanocrystal , magnet , cooling capacity , composite material , magnetic field , magnetization , condensed matter physics , nanotechnology , thermodynamics , crystallography , alloy , chemistry , physics , quantum mechanics
The Gd-based amorphous/nanocrystal composite is prepared by controlling the cooling rate and the element ratio. The X-ray diffraction, differential scanning calorimeter and atomic force microscope/magnetic force microscope are used to confirm the composite microstructures from different perspectives. The magnetic test shows the great enhancement of magnetocaloric effect in the metallic glassy composite. The large magnetic refrigerant capacity (RC) up to 103 J. kg-1 is more than double the RC values of the Gd-based bulk metallic glass and pure Gd. The full width at half maximum of the magnetic entropy change (Sm) peak almost spreads over the whole low-temperature range, which is five times wider than that of the pure Gd. The maximum Sm approaches a nearly constant value in a wide temperature span (over 80 K). The super paramagnetic nanoclusters of the composite increase the magnetic refrigerant capacity greatly. In combination with the low magnetic hysteresis and large resistance, the metallic glass composite may be a potential candidate for the ideal Ericsson-cycle magnetic refrigeration.