Effects of annealing on the magnetic entropy change and exchange bias behavior in melt-spun Ni-Mn-In ribbons

Heusler alloy Ni48Mn37In13 ribbons were prepared by melt-spinning. Post-annealing increases the martensitic transformation temperature T-M and the Curie temperature T-C of the austenitic phase. The maximum magnetic entropy changes Delta S-M(max) in the annealed ribbons are 30.1 and -6.5 J kg(-1) K-1 in the vicinity of T-M and T-C, respectively, for a field change of 3980 kA m(-1). Exchange bias effects are also found in the ribbons. The effects of annealing on the physical properties are discussed. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.