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The coercive field of soft magnetic ferromagnets is a structure-sensitive property and, in particular, is substantially affected by residual stresses. In the present study, the phase and structural states and residual stresses of the FeTiB and FeZrN films of various compositions, which were prepared by magnetron deposition on glass substrates and subsequent 1-h annealing at temperatures of 200–600 °C, were investigated by X-ray diffraction. The formation of a nanocrystalline structure is observed. It comprises different phases having different lattice parameters and unit-cell volumes and is characterized by high level of microstrains of grains as well; the microstrains predetermine the formation of high compressive stresses in the deposited films. As the annealing temperature increases, the compressive stresses decrease and, at certain temperatures, gradually transform into thermal tensile stresses, which are induced by the difference in the thermal expansion coefficients of the film and substrate. Thus, the heat treatment is the efficient way to improve the soft magnetic properties of the studied class of film materials produced by magnetron deposition.

A method for direct measuring the magnetostriction of ferromagnetic films (deposited on nonmagnetic substrates) in using an atomic force microscope was suggested. In measuring the magnetostriction for films 10 [mm] in length and 0,2 [μm] in thickness, which were deposited on substrates 200 [μm] thick, the minimum measured magnetostriction magnitude is ~10-7. The procedure was tested for Ni and Fe films. The magnetostriction magnitudes measured for the films are comparable with those obtained by other magnetostriction-measuring methods. The effect of alloying with zirconium and nitrogen on the magnetostriction of nanocrystalline Fe films was studied.

To design films with the Fe/TiB2 nanocomposite structure, which are characterized by high saturation induction Bs, the phase and structural states and static magnetic properties of Fe‐TiB2 films prepared by magnetron sputtering and subjected to subsequent annealing have been studied. According to X‐ray diffraction data, either amorphous or nanocrystalline single‐phase structure (an α‐Fe(Ti,B) supersaturated solid solution with a bcc crystal lattice) is formed in the as‐sputtered films. Depending on the film composition, the grain size of the α‐Fe(Ti,B) phase varies from 45.6 to 6.5 nm; grains are characterized by high microstrain (0.21‐4.96%). The annealing at 200‐500 °C leads to a decrease in the lattice parameter of the α‐Fe(Ti,B) phase, i.e. to its depletion of titanium and boron and to the formation of two‐phase α‐Fe + Fe3B structure after annealing at 500 °C. The annealing at 200‐500 °C almost does not affect the grain size and microstrain of the bcc α‐Fe‐based phase. The amorphous state of the films is stable up to 500 °C. All studied films are ferromagnets; the saturation induction Bs(0.95‐2.13 T) and coercive field Hc (0.4‐5 kA/m) of the films were determined. Correlations between the Bs and Hc magnitudes and the chemical composition of the films, their phase and structural states and magnetic structure are discussed. (© 2016 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)