Structure, crystallization and magnetic behaviour of Fe-RE-Cu-Si-B alloys (RE = Pr, Nd, Gd)

Nb was replaced by RE atoms (Gd, Pr, Nd) in classic FINEMET and the influence of this substitution on the structure, crystallization and magnetic behaviour was investigated. Thermomagnetic measurements, TEM and XRD observations have shown that Gd and Pr are suitable for grain growth suppressing during crystallization and take part in formation of nanocrystalline structure. The crystallization kinetics of the Nd containing sample is entirely different. Coercivity reflects the structural changes of the sample during annealing. Low-temperature magnetization measurements enable the study of annealing behaviour of the magnetic moment µFc+RE and of the spin-wave stiffness constant. DSP. The results suggest that the light rare-earth Pr and Nd atoms couple ferromagnetically, while the heavy rare-earth Gd atoms couple ferrimagnetically to Fe atoms. The influence of RE atoms on Curie temperature was also observed