Study on magnetic properties of (Nd0.8Ce0.2)2−xFe12Co2B (x = 0–0.6) alloys

Abstract

In the present work, (Nd0.8Ce0.2)2−xFe12Co2B (x=0–0.6) permanent alloys are prepared by melt-spinning method. The hard magnetic properties of (Nd0.8Ce0.2)2−xFe12Co2B (x=0–0.6) alloys annealed at optimum temperatures have been investigated systematically. Depending on the Nd, Ce concentration, the maximum energy product ((BH)max) and remanence (Br) increase gradually with x in the range of 0≤x≤0.4, whereas decrease gradually in the alloys with 0.4<x≤0.6. It is found that the optimum magnetic properties are obtained at x=0.4: Hci=4.9kOe, Br=10.1kG, (BH)max=13.7MGOe. Specifically, magnetic field heat treatment below the Curie temperature is applied for (Nd0.8Ce0.2)1.6Fe12Co2B (x=0.4) annealed ribbons. The magnetic properties Br, (BH)max and squareness are all enhanced after the magnetic field heat treatment. The (BH)max shows a substantial increase from 13.7MGOe to 16.0MGOe after the heat treatment at 623K with a magnetic field of 1T, which gets 17% improvement compared with that of the sample without a magnetic field heat treatment. We demonstrate that the magnetic field heat treatment plays a certain role in the magnetization reversal behavior and can improve the microstructure of (Nd0.8Ce0.2)1.6Fe12Co2B alloy.