MAGNETIC-PROPERTIES OF THIN-FILMS OF FECURSIB TYPE ALLOYS (R-RARE EARTH)

As a continuation of our investigation of FINEMET alloy thin films, Fe 7.35Cu1Nb3Si13.5B9, with Nb replaced by other high-melting metals W: M o, Ta, V [1.5], in this work we report studies on the alloys in which these refractory elements were replaced by the following representativ es of lanthanides: Yb, Ho, Tb, Gd, Sm, Nd, Pr and Y as an element with out a magnetic moment [9]. Their structure was determined on the basis of electron diffraction studies and TEM observations. The structure o f as-deposited films was found to be strongly dependent on the deposit ion conditions. The films deposited for less than 30 seconds were amor phous whereas those deposited for a longer time revealed microcrystall ine structure (the temperature of the evaporation source was the same for all samples). The coercive field H-c in the film plane and the Hal l extraordinary coefficient R-1 together with the value of magnetic sa turation induction B-s for the films of both types were determined fro m the magnetooptical Faraday effect and the Hall effect, respectively. A strong correlation between the magnetic behaviour and structural ch anges of the films was found, i.e., a strong increase in H-c and decre ase in R-1 with increasing annealing temperature were observed.