Magnetic Properties of (Pr1−xSm x )2Fe14B Melt-Spun Ribbons

The magnetic properties of (Pr1−xSm x )2Fe14B melt-spun ribbons with varying x from 0 to 1.0 have been studied. The optimum magnetic property of Pr2Fe14B ribbon could be obtained with the surface velocity of copper wheel of 30 m/s. By melt spinning method, the formation of α-Fe impurity phase in the (Pr1−xSm x )2Fe14B samples could be inhibited, and the grain could be aligned. Sm element could be incorporated into Pr2Fe14B main crystalline phase and formed (Pr,Sm)2Fe14B phase with space group P42/mnm. The Curie temperature (Tc) of the (Pr1−xSm x )2Fe14B ribbons increases gradually from 555 to 617 K with the increase of Sm content x. Both the coercivity (Hc) and remanence ratio (Mr/Ms) decrease firstly and then increase with the Sm content increasing. As long as the Sm content x does not exceed 0.1, the squareness of demagnetization curve remains good. The critical value of transition from easy c-axis to easy plane for (Pr1−xSm x )2Fe14B ribbons is x= 0.6. When the Sm content x is up to 0.6, all the Hc and Mr/Ms achieved the minimum value, i.e., 243 Oe and 0.346, respectively.