Magnetic properties and microstructure of nanocrystalline soft magnetic Fe73.5−x Co x Cu1Nb3Si13.5B9 alloys

The influence of the annealing temperature, cooling rate, and magnetic field frequency in thermomagnetic treatment on the magnetic parameters of nanocrystalline Fe_73.5?x Co _x Cu₁Nb₃Si_13.5B₉ (x=0, 10, 20, and 30) alloys has been investigated. It has been revealed that a thermomagnetic treatment in a dc magnetic field of the nanocrystalline alloys containing cobalt leads to a shift of their hysteresis loop. With increasing Co content in the alloy, the shift of the hysteresis loop increases. This fact is, apparently, connected with the precipitation of α-Co and β-Co clusters and (Fe,Co)₃Si and (Fe,Co)₂B nanophases in which the magnetization direction is determined by the direction of the magnetic field during treatment.