Since the discovery of rare earth metal based permanent magnets discussions took place concerning the leading hardening mechanism, either nucleation or pinning or a mixture of both. This paper deals with experimental results suitable to decide between the relevant hardening mechanism. The following methods will be considered: 1. Dependence of the coercive field on the applied magnetic field. 2. Angular dependence of the nucleation and coercive field in the case of single domain particles and oriented sintered permanent magnets. 3. Analysis of the temperature dependence of the coercive field. It will be shown that a comparison of experimental results leads to a consistent interpretation of the relevant hardening mechanism.
展开▼
