Thermal remagnetization in permanent magnets

Abstract

A mechanism of the thermal remagnetization (TR) of permanent magnets and different approaches to model description of it are discussed, based on both prevailing and new studies. It is noted that TR must be considered as a special case of magnetization reversal processes. It is shown that the conditions for TR in the magnets demagnetized in the asymmetrical way are the possibility of metastable single-domain states of the grains and the high magnetic susceptibility of the multi-domain grains. The effect of coercivity on TR is analyzed. The concept of a realistic TR model for nucleation-type magnets is formulated and the results of numerical simulation carried out under a mean-field approximation are reported.