The comparison of magnetic properties of nanocrystalline Fe-M-Cu-Nb-Si-B (M = Co, Ni) thin films and ribbons

An attempt is made to study the structure and the magnetic properties of the films of Fe-M-Cu-Nb-Si-B (M = Co. Ni) alloys. Thin films have been prepared by ion beam sputtering. The structural observations showed the process of thin film crystallization after annealing. The differences of magnetic domain structure depending upon the heat treatment were observed. The influence of annealing temperature on the coercivity was examined. The minimum of the coercivity was shifted from one annealing temperature of 550°C for ribbons to temperature range 350°C-420°C for thin films and the minimal value of the coercivity of thin films is about 50 times higher than that one for ribbons