The Influence of Sn Addition on the Magnetocaloric Effects, Magnetic and Mechanical Properties of Fe<sub>2</sub>P-Type Mn-Fe-P-Si Compounds

Mn 1.25 Fe 0.65-x Sn x P 0.50 Si 0.50 (0, 0.02, 0.04, 0.05, 0.06, 0.08, 0.09, 0.10, 0.20) series compounds were prepared by mechanical alloying and solid-phase sintering, and their mechanical and magnetic properties were studied. The XRD measurement results show that all the compounds crystalize in Fe 2 P hexagonal structures, with a space group of P-62m. With the increase in Sn content, the compressive strength is significantly improved, the Curie temperature of the compound gradually decreases, and the nature of magnetic transition is tuned from a weak to strong first-order one, which is confirmed by the increase of thermal hysteresis of the compounds. The maximum magnetic entropy change of the compound increases from 9.3 J/kg·K at x = 0 to 17.2 J/kg·K at x = 0.04 under a magnetic field change of 0 - 3 T.