Effect of CeO₂ doping on the coercivity of 2:17 type SmCo magnets

The effects of CeO₂ doping on the magnetic properties and microstructure of 2:17 type SmCo magnets are studied. With the increase of CeO₂ from 0 wt.% to 3 wt.%, the coercivity of the magnets increases from 22.22 kOe to over 29.37 kOe, which is an increase of more than 30%. When the doping content is lower than 1 wt.%, the remanence and magnetic energy product of the magnets remain almost constant. Both decrease sharply as the doping concentration further increases. After CeO₂ doping, the oxide content in the magnet increases significantly and the Ce element is uniformly distributed in the magnet. Observing the magnetic domains reveals that doping with CeO₂ can refine the magnetic domains and make the magnetic domain wall more stable, resulting in a significant increase in the coercivity of the magnets.