(Nd_(0.9)Dy_(0.1))_(16)Co_(5)Fe_(70)Nb_(2)B_(7) PERMANENT MAGNETIC ALLOY AND BEHAVIOUR OF Nb

摘要

The magnetic properties of (Nd_(0.9)Dy_(0.1))_(16)Co_(5)Fe_(70)Nb_(2)B_(7) permanent magnetic alloy prepared by powder metallurgy are:Br=1.08T,_(1)H_(C)=1620kA/m,(BH)_(max)=208kJ/m^(3).The behaviour of Nb in this alloy was studied by joint methods of dynamic observation by high voltage electron microscope(HVEM)and Mossbauer effects.With Nb and Co substituting parts of Fe and adding a little Dy,practical magnetic alloy with excellent properties can be obtained.The thermal stability of it is 80 °C higher than that of ternary Nd-Fe-13 magnet.The study shows that adding Nb into Nd-Fe-B can make the intrinsic coercivity appear peak value at about Nb=2%(in mole fraction).Nb mainly enters into Nd-rich and B-rich phases,a little into Nd_(2)Fe_(14)B phase.