Influence of Cr substitution on the reversibility

Influence of Cr substitution on the reversibility of the magnetocaloric effect in Ni-Cr-Mn-In Heusler alloys

OCTOBER 13, 2021

C. Salazar-Mejía, P. Devi, S. Singh, C. Felser, and J. Wosnitza
Phys. Rev. Materials 5, 104406 (2021)

Abstract


We present the effect of substitution-induced pressure on the reversibility of the magnetocaloric effect (MCE) in Ni2CrxMn1.4−x In0.6 (x = 0.1, 0.2, 0.3) alloys, through characterization in pulsed magnetic fields. We measured the adiabatic temperature change Tad directly during applied magnetic field pulses of 2 and 6 T. We paid special attention to the reversibility of Tad. The substitution of Mn by Cr in Ni2Mn1.4In0.6 leads to a negative pressure, as evidence by the increase of the lattice parameters, which shifts the martensitic transition towards lower temperatures and enhances the ferromagnetism of the martensite phase. We found a large value of Tad = −7 K at T = 270 K for the sample with x = 0.1 for a field change of 6 T. We discuss the reversibility of the MCE in these alloys in terms of the Clausius-Clapeyron equation.
 
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