Effect of cooling rate on the microstructure and magnetic properties of melt-spun CeFeB ribbons

NdFeB permanent magnetic alloys are widely used in industrial applications, particularly in electronics, due to their excellent magnetic performance. However, their dependence on expensive rare earth and neodymium elements has led to supply risks and price instability. As a more abundant and economical alternative, CeFeB alloys have gained attention recently. In this study, CeFeB ribbons with a nominal composition of Ce35Fe64B1 (wt%) were fabricated via melt spinning method at different wheel surface speeds (3-35 m/s). XRD analysis revealed that all of the ribbon samples exhibit partially crystalline structures. They contains the Ce2Fe14B hard magnetic phase, along with soft magnetic alpha-Fe and paramagnetic CeFe2 phases. As the wheel surface speed increased, crystallite size of the Ce2Fe14B phase reduced, and tendency to amorphous phase formation increased. The finest crystallite size of the Ce2Fe14B phase of 26.18 nm was achieved at the wheel surface speed of 5 m/s. Accordingly, the optimum magnetic properties were obtained. These are the coercivity, remanence, maximum energy product, and remanence ratio of 4301.84 Oe, 62.12 emu/g, 10.94 MGOe, and 0.624, respectively. These results highlight the critical role of cooling rate for modifying the microstructure and improving the magnetic performance. This study shows that the CeFeB alloys posses the requisite magnetic performance to serve as competitive, low-cost alternatives to their NdFeB counterparts. Their favorable characteristics highlight a strong potential for integration into large-scale industrial systems where rare earth scarcity and economic viability are of primary concern.