Magnetic Phase Diagram of the Mn x Fe2- xP1- ySi y System

Xinmin You; Michael Maschek; Niels Harmen H van Dijk; Ekkes Brück

doi:10.3390/e24010002

Magnetic Phase Diagram of the Mn _x Fe_{2- x}P_{1- y}Si _y System

Entropy (Basel). 2021 Dec 21;24(1):2. doi: 10.3390/e24010002.

Authors

Xinmin You¹, Michael Maschek¹, Niels Harmen H van Dijk¹, Ekkes Brück¹

Affiliation

¹ Fundamental Aspects of Materials and Energy (FAME), Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands.

Abstract

The phase diagram of the magnetocaloric Mn_xFe_2-xP_1-ySi_y quaternary compounds was established by characterising the structure, thermal and magnetic properties in a wide range of compositions (for a Mn fraction of 0.3 ≤ x < 2.0 and a Si fraction of 0.33 ≤ y ≤ 0.60). The highest ferromagnetic transition temperature (Mn_0.3Fe_1.7P_0.6Si_0.4, T_C = 470 K) is found for low Mn and high Si contents, while the lowest is found for low Fe and Si contents (Mn_1.7Fe_0.3P_0.6Si_0.4, T_C = 65 K) in the Mn_xFe_2-xP_1-ySi_y phase diagram. The largest hysteresis (91 K) was observed for a metal ratio close to Fe:Mn = 1:1 (corresponding to x = 0.9, y = 0.33). Both Mn-rich with high Si and Fe-rich samples with low Si concentration were found to show low hysteresis (≤2 K). These compositions with a low hysteresis form promising candidate materials for thermomagnetic applications.

Keywords: Mn-Fe-P-Si; magnetic entropy; magnetocaloric materials; phase diagram; thermal hysteresis; transition temperature.

Abstract

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