High‐induction nanocrystalline soft magnetic Fe X Ti Y B Z films prepared by magnetron sputtering

To design films with the Fe/TiB 2 nanocomposite structure, which are characterized by high saturation induction B s , the phase and structural states and static magnetic properties of Fe‐TiB 2 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 + Fe 3 B 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 B s (0.95‐2.13 T) and coercive field H c (0.4‐5 kA/m) of the films were determined. Correlations between the B s and H c 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)