Application of the Mössbauer Effect and Magnetic Studies of Bulk Amorphous Fe–Co–B Alloys

This work presents the results of studies of the bulk amorphous Fe70Nb5Y5B20 alloy produced by two methods, i.e., suction casting and combined injection–suction casting. Plates with a thickness of 0.5 mm were obtained. The aim of the study was to determine the effect of the production method on the structural state, hyperfine structure, and magnetization process of the alloy. The sample structure was examined using X-ray diffraction. For both samples, a broad diffraction maximum characteristic of an amorphous material was obtained. Mössbauer spectra recorded at room temperature contained broad Zeeman components and an additional paramagnetic component. Analysis of the hyperfine-field distributions revealed differences in the local environment of Fe atoms depending on the production method. The static hysteresis loops had a shape typical of soft magnetic materials. Analysis of the initial magnetization curves was used to identify the mechanisms governing the approach to saturation, and the spin-wave stiffness parameter was determined in the high-field range. The results indicate that, while the amorphous character of the material is preserved, the production method can affect the local magnetic structure and the course of the magnetization process.