Magnetocaloric effect in Ni-Mn-X Heusler alloys
Abstract: Effect of replacement of Ga by Sn for two Ni-rich Heusler alloys series: Ni50Mn25+aX25-a (a=0; 2.3; 4.2; 5.8; 7.15; 8.35), with X= Ga, Sn, and its influence on the magnetocaloric properties of the alloys, were studied. The XRD studies revealed that Sn substitution for Ga results in the fact that all alloys exhibit the same austenitic structure, with no evidence of structural transition at room temperature (RT). This was confirmed by magnetic measurements conducted in a low field of 4 kA/m (50 Oe) which showed that the Curie transition temperature are above the RT. The analysis of isothermal magnetic curves allowed the calculation of magnetic entropy change (ΔSM). The highest value of entropy change, |ΔSM| = 2.7 J/kgK in the magnetic field ΔH = 1.5 T, was registered for the Ni50Mn29.20Ga20.80 alloy.
Keywords: magnetocaloric effect, Heusler alloys, magnetic entropy changes
Area: Nanotechnologies and Materials
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.