Mössbauer-effect study of Mg-Al ferrites having a rectangular hysteresis loop

A Mössbauer-effect study was made of Mg-Al ferrites having a rectangular hysteresis loop. The replacement of Fe³⁺ ions by A1³⁺ ions produces an additional component in the Mössbauer spectra, due to second-phase inclusions. The phase composition of the Mg-Al ferrite has a marked effect on the shape of the hysteresis loop. As the second-phase inclusions increase in relative importance, rectangularity coefficient D decreases. Local lattice distortion has a lesser effect on D. At high Al₂O₃ concentrations (above 15 mole%) in the Mg ferrite there is a sharp increase in the coercive force with increasing Al₂O₃ content. This increase is also due to second-phase inclusions.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii Fizika, No. 2, pp. 105–109, February, 1971.In conclusion the authors thank I. I. Sil'vestrovich and B. A. Pavel'ev for furnishing the samples.