Search

The crystal structure, magnetic phase transition, high saturation magnetization, and chemical status of polycrystalline FeB compound were investigated. The results show that a single phase with the CuAl-type tetragonal structure with space group of I4/ mcm is clearly observed, and the Curie temperature is 1017 K. A maximum value of saturation magnetization (M) of 173 Am⋅kg was achieved when the saturated magnetic field was ∼5 kOe at 300 K. Moreover, XPS proved that the chemical status of Fe and B elements existed in the form of FeB in this compound. The polycrystalline FeB compound with large saturation magnetization is economical and non-toxic raw materials, which would be of considerable importance for exploring the potential applications in the magnetic functional material field. [ABSTRACT FROM AUTHOR]

Crystal structural and magnetic properties of polycrystalline (FeMn)Dy ( x = 0.0, 0.1, 0.2, and 0.3) compounds were studied by X-ray diffraction (XRD) and vibrating sample magnetometer (VSM) measurements. The results show that (FeMn)Dy forms as a substitutional solid solution with the hexagonal ThNi type. The unit cell volume increases with Mn content. The Curie temperature ( T ) can be tuned from 364 K for x = 0.0 to 80 K for x = 0.3. The magnetic transition at T is a typical second-order ferromagnetic-paramagnetic transition. For an applied field change from 0 to 5 T, the maximum magnetic entropy change (| − Δ S |) for (FeMn)Dy ( x = 0.0, 0.1, and 0.2) compounds are 3.9, 2.8, and 1.7 J kg k, respectively. The high Δ S , appropriate T , and a high performance-to-cost ratio make (FeMn)Dy compounds a candidate materials for room-temperature magnetic refrigeration applications. [ABSTRACT FROM AUTHOR]