The coercive field, H{sub}c, in rapidly quenched Nd-Fe-B was found to increase for samples with excess of Nd. In addition, H{sub}c strongly depends on the Fe/B ratio, increasing from 1.67 T for Fe/B = 1.07 to 2.05 T for Fe/B = 14.6 inNd{sub}30(Fe,B){sub}70. The increase in H{sub}c seems to correlate with an increase of the γ-Nd phase in the sample. The initial magnetization curves of Nd{sub}30(Fe,B){sub}70 show that the domain wall pinning plays a more important role as the Fe/Bratio increases. Thus, γ-Nd may play an important role in promoting a pinning mechanism. The excess of Nd in rapidly quenched Nd-Fe-B samples was also found to promote growth of Nd{sub}2Fe{sub}14B grains elongated in shape.
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