Effects of Indium on PrCo$_{5}$ Magnets Prepared by Powder Sintering and Hot-Deformation of Nanocrystalline Precursors

Small additions of indium are found to introduce low-melting-temperature phases in PrCo
₅
-based magnets. The sintering temperature of anisotropic powders with 0.5 at.% indium can be reduced from 1100degC to 950degC-975degC, resulting in increase of remanent magnetization of the optimally heat-treated sintered magnet from 9 to 10.7 kG with a simultaneous increase of the intrinsic coercivity from 6.7 to 9.1 kOe. In the magnets prepared by hot deformation of nanocrystalline precursors, the indium-induced grain-boundary phase(s) strongly promotes uniaxial alignment of the [100] direction rather than the desired [001] easy magnetization direction.