Magnetic Inhomogeneities in BaO B₂0₃ - Fe₂O₃ Oxide Glasses

Abstract

Metastable oxide glasses, rich in iron oxide, are known^1–7 to develop interesting magnetic properties as crystalline ferritic phases precipitate on suitable heat treatment. While some of the investigations were primarily concerned with identifying the crystalline phases formed and others studied mainly the magnetic properties, both groups implicitly assumed that the precipitates were homogeneous. In this paper we describe an investigation in which the magnetic properties and the microstructure of an inhomogeneous glass of this type produced by heat treatment were simultaneously measured. This investigation showed that the precipitates were not only bimodally distributed in size but in addition were not homogeneous in structure. Some interesting magnetic behavior due specifically to the inhomogeneity of the precipitate is described.