Study on magnetization reversal behavior for annealed Nd2Fe14B/α-Fe nancomposite alloys

Effect of thermal annealing on the magnetization reversal behavior of alpha-Fe/Nd2Fe14B alloys was investigated. A drastic increase of the remanence M-r from 0.67 up to 0.87 T and remanence ratio M-r/M-s from 0.66 up to 0.76, respectively, was observed in the alpha-Fe/Nd2Fe14B alloys annealed at 610 degrees C as compared with the as-quenched sample. Whereas the further annealing at 680 degrees C resulted in a strong increase of the corecivity H-c as high as 491 kA/m but a slight decrease in M-r. The analysis result of the magnetization reversal behavior showed that the maximum value of the integrated recoil loop area about 1.58 kJ/m(3) was obtained in the alpha-Fe/Nd2Fe14B alloys at the annealing temperature of 610 degrees C, significantly lower than other annealed samples. This indicated a significant advantage for the application of this material as permanent magnets in electrical machines and generators due to a low energy loss.