Intergranular phase dependence of anisotropy and coercivity in nanoscaled permanent magnets

Abstract In order to understand the effect of intergranular phase on magnetic properties, we assume that the intergranular phase is nonmagnetic phase and studied the effect of intergranular phase with different thickness d on the effective anisotropy and coercivity of nanocrystalline materials. The results showed that with increasing d , the average anisotropy of grain, 〈 K 〉, of material increases monotonously, while the effective anisotropy, K eff , increases firstly and decreases subsequently, and exhibits maximum value at certain d . The existence of intergranular phase weakens or prevents the exchange-coupling interaction between grains and may result the increase of K eff , and H c of material. The calculated dependence of coercivity on grain size is basically in accordance with the theoretical and experimental results given by other authors.