A first order transition from a paramagnetic-austenite phase to a ferromagnetic-martensite phase occurring in off-stoichiometry single crystals of Ni2MnGa at 313 K presents unique features due to the multifunctional character of the magnetic shape memory alloy. A remarkable magnetocaloric effect, associated with an entropy change up to deltaS=−86 J kg−1 K−1 and an adiabatic temperature change deltaT=2.2 K, accompanied by mechanical strain 3% have been observed in samples subjected to changes of the applied magnetic field deltaH =4106 A/m 5 T. The effects of magnetic field, temperature, and stress on the entropy variation S are quantified and compared.
Magnetostructural transition and magnetocaloric effect in Ni55Mn20Ga25 single crystals / Pasquale, Massimo; Sasso, CARLO PAOLO; Lewis, L. H.; Giudici, L.; Lograsso, T.; Schlagel, D.. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1550-235X. - 72:(2005), p. 094435. [10.1103/PhysRevB.72.094435]
Magnetostructural transition and magnetocaloric effect in Ni55Mn20Ga25 single crystals
PASQUALE, MASSIMO;SASSO, CARLO PAOLO;
2005
Abstract
A first order transition from a paramagnetic-austenite phase to a ferromagnetic-martensite phase occurring in off-stoichiometry single crystals of Ni2MnGa at 313 K presents unique features due to the multifunctional character of the magnetic shape memory alloy. A remarkable magnetocaloric effect, associated with an entropy change up to deltaS=−86 J kg−1 K−1 and an adiabatic temperature change deltaT=2.2 K, accompanied by mechanical strain 3% have been observed in samples subjected to changes of the applied magnetic field deltaH =4106 A/m 5 T. The effects of magnetic field, temperature, and stress on the entropy variation S are quantified and compared.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
