Abstract:Compared with different exchange coupling models of one-dimensional to three-dimensional nanocomposite permanent magnet materials, exchange coupling will inhibit the magnetization reversal of soft magnetic phase, and different exchange coupling models have different effects on coercivity. The higher δM peak of Henkel curve indicates the stronger exchange coupling between grains. The peak of the first order reversal curve ( FORC ) corresponds to the exchange coupling. The effective anisotropy Keffof nanocomposite permanent magnet decreases with the decrease of grain size. When the grain size is constant, the higher the volume fraction of soft magnetic phase is, the lower the Keff is. In order to obtain nanocomposite permanent magnetic materials with high maximum energy product, the grain size of soft magnetic phase should be about 10 nm, and the volume of soft magnetic phase should not exceed 50 %.