Hollow spheres of hexagonal ferrite BaCozFelrO27 were fabricated through a spray pyrolysis technique using co-precipitation ferrite powder precursor as materials, followed by calcinations in an air atmosphere. The pha...Hollow spheres of hexagonal ferrite BaCozFelrO27 were fabricated through a spray pyrolysis technique using co-precipitation ferrite powder precursor as materials, followed by calcinations in an air atmosphere. The phase composition, micro-morphology, and static magnetic property of the particles were measured by XRD, SEM, and VSM. The results indicate that the method for preparation of ferrite hollow microspheres （FHM） results in a broad particles size distribution. The density of FHM decreased from 5.31 g/ cm^3 to 2.31 g/cm^3. When the heating rate was 5℃/min, and temperature was 1 200℃ for 4 hours, pure W-type ferrites were formed. With the heat treatment temperature and time increasing, the crystal structure becomes perfect, the saturation magnetization is increased and the coercive force is decreased.展开更多
基金Funded by 863 HI-TECH project(No.2002AA305302) Supported by Shanghai Leading Academic Discipline(No.P1304)
文摘Hollow spheres of hexagonal ferrite BaCozFelrO27 were fabricated through a spray pyrolysis technique using co-precipitation ferrite powder precursor as materials, followed by calcinations in an air atmosphere. The phase composition, micro-morphology, and static magnetic property of the particles were measured by XRD, SEM, and VSM. The results indicate that the method for preparation of ferrite hollow microspheres （FHM） results in a broad particles size distribution. The density of FHM decreased from 5.31 g/ cm^3 to 2.31 g/cm^3. When the heating rate was 5℃/min, and temperature was 1 200℃ for 4 hours, pure W-type ferrites were formed. With the heat treatment temperature and time increasing, the crystal structure becomes perfect, the saturation magnetization is increased and the coercive force is decreased.
