Barium (Bag) ferrite ultra fine powders were synthesized by using sol-gel in which polyethylene glycol 200(PEG200) was used as gelling agent. The transition of Ba ferrite was studied by thermal gravimetric and differe...Barium (Bag) ferrite ultra fine powders were synthesized by using sol-gel in which polyethylene glycol 200(PEG200) was used as gelling agent. The transition of Ba ferrite was studied by thermal gravimetric and differential thermal analysis (TG-DTA) technology. The micro structural changes were analyzed using X-ray diffraction (XRD) and atomic force microscopy (AFM) for the specimens annealed at different temperatures. The transition temperatures were 414.55°C and separately corresponding to BaFe2O4 and BaFe,2O19. There were three types of microstructures for Ba ferrite ultrafine powder specimen annealed at 800°C. For the specimens annealed at different temperatures, there were different kinds of Ba ferrites. The ferrite powder consists of BaFet2O19 and BaFe2O4 for the specimen annealed at 800°C, and only BaFe^O^ can be found in the specimen annealed at 1000°C. The magnetic properties, a , and H c of BaFC|2O19 ultrafine powders are different from that of BaFe12O19 bulk material.展开更多
文摘Barium (Bag) ferrite ultra fine powders were synthesized by using sol-gel in which polyethylene glycol 200(PEG200) was used as gelling agent. The transition of Ba ferrite was studied by thermal gravimetric and differential thermal analysis (TG-DTA) technology. The micro structural changes were analyzed using X-ray diffraction (XRD) and atomic force microscopy (AFM) for the specimens annealed at different temperatures. The transition temperatures were 414.55°C and separately corresponding to BaFe2O4 and BaFe,2O19. There were three types of microstructures for Ba ferrite ultrafine powder specimen annealed at 800°C. For the specimens annealed at different temperatures, there were different kinds of Ba ferrites. The ferrite powder consists of BaFet2O19 and BaFe2O4 for the specimen annealed at 800°C, and only BaFe^O^ can be found in the specimen annealed at 1000°C. The magnetic properties, a , and H c of BaFC|2O19 ultrafine powders are different from that of BaFe12O19 bulk material.
