Micromagnetic Analysis on Demagnetization Process of Single-Phase Nanocrystalline Permanent Magnets with Different Degrees of Orientation

摘要

A three-dimentional finite element micromagnetic algorithm was developed to study the magnetization reversal of Pr2Fe 14 B single-phase nanocrystalline permanent magnets. A single-phase nanocrystalline Pr2Fe 14 B magnets composed of 216 irregular shaped grains was built. The magnetic hysteresis loops were simulated by micromagnetic finite element method. The contribution of intergrain exchange coupling （IGEC） to remanence enhancement is considered related to the alignment degree in oriented magnets, and decreased with improved grain alignment. For the magnets with perfectly crystallographic alignment of grains, the contribution of IGEC to remanence enhancement is nearly zero. The shape of demagnetization curve is not only dependent on grain alignment degree but also on the strength of IGEC in magnets.