Discussion of the coercivity mechanism of RE-TM-B permanent magnets

Abstract
It can be shown that the initial magnetization curves of DC demagnetized samples are well below those of thermally demagnetized samples, which has been explained by a localised weak-domain wall pinning model. The calculated results showed that there is no 0.3 limit for alpha kpin values. Therefore the value of 0.3 for the alpha kpin parameter is not a valid criterion by which to determine the coercivity mechanism.