Calculations of demagnetization curves of Nd-Fe-B magnets based on inhomogeneous nucleation

Demagnetization curves of Nd-Fe-B magnets are evaluated based on the micromagnetics for inhomogeneous nucleation by considering a magnetic planar defect. The inhomogeneous nucleation field, reduced due to the magnetic defect, is increased as an effect of the second anisotropy constant, K/sub 2/, even though K/sub 1/>4K/sub 2/ is satisfied, where K/sub 1/ is the first anisotropy constant. Further, the demagnetization process under the condition where the spin structure is conical is also examined in the case of -2K/sub 2/>