Effects of the grain alignment on the coercivity and its angular dependence for NdCoFeB permanent magnets

The dependence of the macroscopic magnetism for NdCoFeB permanent magnet on the degree of grain alignment has been studied. With an increase in grain alignment degree, the coercivity of the permanent magnet decreases and the remanence increases. The decrease rate of the coercivity is smaller than the increase rate of the remanence. The coercivity Hc(θ) increases with increasing angle θ between the applied field and the texture axis, and for the permanent magnets with good grain alignment the increase rate of Hc(θ) is large. These experimental results can be interpreted by using the starting field theory of coercivity.