Abstract:
A study of magnetocaloric effect in amorphous and partially crystallized
Fe40Ni38Mo4B18 alloys is reported. Amorphous Fe40Ni38Mo4B18, near its magnetic
ordering temperature (600K) showed a magnetic entropy change ΔSM of 1.1 J/KgK
and a relative cooling power of 36J/Kg in a field change of 10 kOe. Amorphous
samples were partially crystallized by annealing at 700 K at different time intervals.
Partially crystallized samples showed two distinct magnetic ordering temperature,
one corresponding to the precipitated FeNi nanocrystals and the other one corresponding
to the boron rich amorphous matrix. Magnetic ordering temperature of the
residual amorphous matrix got shifted to the lower temperatures on increasing the
annealing duration. Partially crystallised samples showed a magnetic entropy change
of about 0.27J/kgK near the magnetic ordering temperature of the amorphous matrix
(540K) in a field change of 10 kOe. The decrease in ΔSM on partial crystallisation
is attributed to the biphasic magnetic nature of the sample. C 2016 Author(s). All
article content, except where otherwise noted, is licensed under a Creative
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