無容器凝固における酸化物の相選択

Small spherical samples of BaFe12O19 were fully melted in O2 gas flow with an aero-acoustic-levitator device and subsequently rapid cooled by splat quenching. For samples heated above the liquidus, the microstructure and XRD observations suggested the formation of the amorphous phase with small amount of Fe2O3. The sample undercooled below liquidus temperature and splat-quenched at a temperature below the peritectic temperature show a microcrystalline microstructure of the BaFe12O19 phase, that was confirmed by XRD. This indicates that the BaFe12O19 phase was solidified directly from the undercooled melt.