| Nd Fe B/Fe3 P composite permanent magnetic materials were prepared by direct synthesis method. The structure and magnetic properties of preparation samples are measured by using XRD、VSM(0-1.5T)and we analyzed and found that decreasing the melting point(1166 ℃)of Fe3 P by the eutectic reaction can slow down the rate of decrease of the coercive force caused by the increasing soft magnetic phase. It is preliminarily considered that the decreasing melting point of Fe3 P makes soft magnetic phase Fe3 P form crystal thin layer in the crystal boundary.Nd3-xPrxFe27.7Ti1.3(0≤x≤2.5)series compounds were prepared by using vacuum arc melting and high-temperature quenching methods. The structure and magnetic properties of preparation samples are studied by using XRD、VSM. The X-ray diffraction results of powder samples and room-temperature conventional orientation samples shows that the series compounds belong to the Nd3(Fe,Ti)29-type monoclinic system structure and space group is A2/m. With addition Pr element, the cell volume and lattice parameter slightly increased. The magnetocrystalline anisotropy of the series compounds switched from surface anisotropy to uniaxial anisotropy when it is from x = 0.5. After that, it returns surface anisotropy again when x is equal to 2.5. The M-B measurement data in different temperatures indicate that the anisotropy field(Ba), saturation magnetizations(Ms) and Curie temperature trends to increase firstly and decline latterly with Pr addition. When x=0 and 2.0,The spin reorientation phenomena is observed. |
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