Fe-P based nanocrystalline alloys with good soft-magnetic properties via Nb microalloying

The demand for nanocrystalline alloys with excellent soft magnetic properties as well as satisfactory process-ibility leads to the development of Fe-P based nanocrystalline alloys. In this work, Fe-P based Fe85.5-xP11C2B1Cu0.5Nbx (x=0, 0.1, 0.3, 0.5, 1.0 and 1.5) nanocrystalline alloys with high saturation magnetization (Bs), low coercivity (Hc), wide annealing temperature range, large annealing duration interval and good bending ductility are successfully prepared through Nb microalloying. This kind of nanocrystalline alloy exhibits high Bs and low Hc in the range of 1.41-1.81 T and 2.41-12.03 A/m. Especially, Fe85.4P11C2B1Cu0.5Nb0.1 alloy shows optimal soft magnetic properties, with high Bs of 1.81 T and low Hc of 5.4 A/m. All alloys maintain low Hc after ten-minute heat treatment at various temperatures of up to Tx2, proving high stability during heat treatment, as evidenced by microstructure characterization, domain observation and thermal analysis. The newly developed Fe85.4P11C2B1Cu0.5Nb0.1 alloy, with high Bs, low Hc, good processibility and low-cost advantage, provides a promising candidate for high-performance soft magnetic applications.