Effect of mini Ga doping in nanocrystalline Nd_4.5(Fe,Co)_(77.5)B_(18) magnet on coercivity

摘要

The microstructure and the coercivity of nanocomposite Nd_(4.5)Fe_(76.5-x)Ga_xCo_(1.0)B_(18) (x=0～0.6at%)bonded magnets were studied. The results showed that addition of small amount of Ga in Nd_(4.5)Fe_(76.5-x)Ga_xCo_(1.0)B_(18) made the grains finer and more uniform. A notable peak of coercivity was observed in the variational curve of coercivity with annealing time when Ga content was low (x=0.2). This phenomenon could be explained by the microstructure and the exchange coupling interaction of two-phase nanocomposite.