High energy magnets from PrCo5

PrCo
5
permanent magnets have been produced with energy products ranging up to 26 MGOe and which are magnetically and chemically stable. These magnets typically have remanence of ∼ 10.5 kG and a coercive force of 4 to 5 kOe. The maximum energy product achieved is only about 60% of that theoretically possible, 39 MGOe. The low coercive force is ascribed to impurity phases Pr
5
Co
19
or Pr
2
Co
17
, which are formed in the sample as a result of oxidation or of imperfect compensation for the effects of oxidation.