Magnetocaloric and Shape-Memory Properties in Magnetic Heusler Alloys
In this paper, we discuss the magnetocaloric behavior of Ni-Mn-based Heusler alloys in rela- tion to their shape-memory and superelastic properties. We show that the magnetocaloric effect in these materials originates from two different contributions: (i) the coupling that is related to a strong uniaxial magnetic anisotropy and takes place at the length scale of martensite variants and magnetic domains (extrinsic effect), and (ii) the intrinsic microscopic magnetostructural coupling. The first contribution is intimately related to the magnetically induced rearrange- ment of martensite variants (magnetic shape-memory) and controls the magnetocaloric effect at small applied fields, while the latter is dominant at higher fields and is essentially related to the possibility of magnetically inducing the martensitic transition (magnetic superelasticity). The possibility of inverse magnetocaloric effect associated with these two contributions is also considered.
Lluis Mañosa, P.K. Mukhopadhyay and S.R. Barman
A. Planes et al., "Magnetocaloric and Shape-Memory Properties in Magnetic Heusler Alloys", Advanced Materials Research, Vol. 52, pp. 221-228, 2008