Effect of respective additions of Ga, Zr and combined additions of Co, Ga,Zr on magnetic properties of remanence-enhanced Nd8.4Fe87.1B4.5 alloy

The effect of a partial substitution of Zr; Ga; Co and Ga; Co, Ga and Zr; r espectively for Fe on the structure and magnetic properties of Nd8.4Fe87.1B 4.5 alloy prepared by mechanical alloying has been studied in detail. It ha s been shown that, intrinsic coercivity mu(o)H(c), and maximum magnetic ene rgy product (BH)(max) increase for only Zr or Ga-containing samples, which is mainly due to the refinement of soft grains. The combined addition of Co and Ga is less effective for improving mu(o)H(c) and (BH)(max) than the re spective addition of Co or Ga, which may be due to the formation of CsCl-ty pe CoGa. mu(o)H(c) and (BH)(max) for combined Co, Ga, Zr-added alloy are hi gher than those for the combined Co, Ga-added alloy but lower than those fo r only Zr-containing alloy.