Highly anisotropic resin-bonded magnets processed with surfactant-coated SmCo5 nanocrystalline powders

Highly anisotropic SmCo5 nanocrystalline powders with grain size in the range 5–20 nm were processed through surfactant and magnetic field-assisted milling. The SmCo5 nanocrystalline powders so obtained by this method possess unusual characteristics such as reduction in particle size, platelet-structure and high remanence values. A possible mechanism for achieving remanence enhancement with the surfactant-coated SmCo5 powders has been discussed. Besides, the resin-bonded magnets processed with the surfactant-coated SmCo5 powders showed relatively higher density, induction remanence and energy product with strong anisotropic behavior than those of the magnets processed with the conventionally milled SmCo5 powders. Maximum values of Hci (16 kOe), Br (4.66 kG) and (BH)max (5.5 MG Oe) were achieved for the resin-bonded magnets processed with the surfactant-coated powders.