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arXiv · 2402.04940

On correctly assessing the reversibility of the magnetocaloric effect from indirect measurements

R. Kiefe·R. Almeida·J. H. Belo·J. S. Amaral
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Abstract

The adiabatic temperature change ($\Delta T_{ad}$) of a magnetic refrigerant can be indirectly estimated through field ($H$) and temperature ($T$) dependent magnetization ($M$) and specific heat ($C_p$) measurements. A direct integration approach for this estimation is frequently reported, which is an approximation to a rigorous mathematical approach. In this work, we propose an iterative method in small $H$ steps, to estimate $\Delta T_{ad}$ from indirect measurements. We show that this approach is able to reproduce the reversibility of the magnetocaloric effect, and provides a more accurate estimation of $\Delta T_{ad}$, up to 10\% when considering a detailed $M(H,T)$ and $Cp(H,T)$ dataset that reproduces the magnetothermal properties of gadolinium, a benchmark room-temperature magnetic refrigerant.

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R. Kiefe, R. Almeida, J. H. Belo, J. S. Amaral. 2024-02-07. On correctly assessing the reversibility of the magnetocaloric effect from indirect measurements. https://arxiv.org/abs/2402.04940

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