Mossbauer study of the material of the electric power transformers

Fe-Si alloy is a soft magnetic material used as the core of electric power transformers. One method of molding the core is to press the powdered alloy into the shape of the core. In our study, the X-ray diffraction measurements performed on this processed material, we observed that the peak intensity of ordered phase Fe3Si was decreased in the pressed sample. The amount of ordered phase is important for the magnetic material. We performed Fe-57 Mossbauer spectroscopy to elucidate this decrease in the ordered phase. The obtained Mossbauer spectra do not show change with or without pressing. This result indicates that the amount of the ordered phase does not decrease in atomic micro-environments upon pressing. The decrease of the peak intensity in X-ray diffraction can be associated with the distortion or deformation of the ordered phase particles. This consideration is also consistent with the FWHM of the Mossbauer spectrum being slightly broadened on the pressed sample.