In situ identification of the metastable phase during solidification from the undercooled YFeO3 melt by fast x-ray diffractometry at 250Hz

Abstract

A time-resolved x-ray diffraction (XRD) experiment at 250Hz using a synchrotron radiation source was carried out during the containerless solidification of ReFeO3 (Re=Y and Lu) in order to identify the metastable phase in situ. The metastable phase solidified primarily from the undercooled YFeO3 melt finally transformed to the stable orthorhombic YFeO3 phase during the short period of recalescence (∼0.035s). Although the metastable phase could not be detected in the as-solidified sample by the powder XRD, the in situ diffraction pattern of the metastable phase in the YFeO3 system was consistent with that of the metastable hexagonal LuFeO3 phase.