Preparation of magnetic composites through SrO-Fe 2O 3-Al 2O 3-B 2O 3 glass crystallization

Abstract

Glasses with nominal compositions 11SrO • 5.5Fe 2O 3 • 4.5Al 2O 3 • 4B 2O 3 (1) and 15SrO • 5.5Fe 2O 3 • 4.5Al 2O 3 • 4B 2O 3 (2) were prepared by rapidly quenching oxide melts between counterrotating steel rollers. The glasses were then heat-treated in the range 650-950°C to produce glass-ceramic samples. The samples were characterized by X-ray diffraction, electron microscopy, and magnetic measurements. The phase composition of the glass-ceramics was determined, and their microstructure and magnetic properties were studied. The annealing temperature was shown to have a strong effect on the coercivity of the materials, which reaches 650 and 570 kA/m for compositions 1 and 2, respectively. © 2009 Pleiades Publishing, Ltd.