Abstract：The first-order phase transition compounds MnFe(P,Si) have been prepared by mechanical alloying and solid-state reaction method, and investigated the structure，magnetocaloric properties and thermodynamic properties. The results show that the obtained MnFe(P,Si) compounds are composed of a main phase of Fe2P-type hexagonal structure with space group P-62m, and a secondary phases of Fe3Si or Fe5Si3, which appeared in some of them. MnFe0.9P0.5Si0.5 crystallizes in single phase with Fe2P-type hexagonal structure, the transitions from ferromagnetic state to paramagnetic state (heating process) and paramagnetic state to ferromagnetic state (cooling process) are appeared at Ttw= 330 K and Ttc= 318 K, respectively. Its thermal hysteresis is ΔThys= 12 K and the transition in heating and cooling process are completed in 10 K, which means these transitions are of first-order phase transition. The maximum value of magnetic entropy change is-ΔSmax= 18.6 J/(kg·K) in a magnetic field change of 0-1.5 T. The maximum heat capacity is Cp=1571 J/(kg·K) (heating process) and Cp=1447 J/(kg·K) (cooling process). Therefore, it can be inferred that MnFe0.9P0.5Si0.5 compound is an excellent candidate material for thermomagnetic power generation.
韩睿，特古斯，欧志强，王莹，国庆. MnFe(P,Si)一级相变热磁发电材料的制备与磁性研究[J]. , 2016, 23(3): 11-16.
HAN Rui, O Tegus, OU Zhi-qiang, WANG Ying, GUO Qing. Investigation on the synthesize and magnetic properties of first-order phase transition thermomagnetic power generation compound MnFe(P,Si). , 2016, 23(3): 11-16.
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2016, Vol. 23 
