Magnetization reversal process in RCo5 particles and sintered permanent magnets

A model relating the nucleation field for particles of R Co5-type permanent-magnet materials (R represents the rare-earth element) to domain wall energy is shown to describe all our experiments, and that it is also consistent with previously reported data for single-crystal particles and powders of SmCo5. The model is also consistent with sintered permanent-magnet data and suggest that a drastic reduction of oxygen pick up in the manufacturing process would greatly improve SmCo5 permanent magnets.