Magnetocaloric properties of a Ni50Mn36Co 1Sn13 ferromagnetic shape memory alloy have been studied experimentally in the vicinity of a first-order magnetostructural phase-transition low-temperature paramagnetic martensite high-temperature ferromagnetic austenite. The magnetic entropy change Δ Sm calculated from the magnetization M (T) data measured upon cooling is higher than that estimated from M (T) measured upon heating. Contrary to Δ Sm, the adiabatic temperature change Δ Tad measured upon cooling is significantly smaller than that measured upon heating. The apparent discrepancy between Δ Sm and Δ Tad (larger Δ Sm, smaller Δ Tad upon cooling, and smaller Δ Sm, larger Δ Tad upon heating) is caused by the hysteretical behavior of this magnetostructural transition, a feature common for all the alloys in the family of Ni50Mn25+xZ25-x (Z=In,Sn,Sb) ferromagnetic shape memory Heusler compounds. The hysteresis causes the magnetocaloric parameters to depend strongly on the temperature and field history of the experimental processes.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - 2010 Jun 7|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics