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

Abstract The effects of doped CeO2 on the magnetic properties and microstructure are studied in 2:17 type SmCo magnets. With the increase of CeO2 from 0 wt.% to 3 wt.%, the coercivity of 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 magnet 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 domain reveals that doping 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.