【摘 要】
：
The hexagonal BaGdxFe12-xO19 (x=0.1～1.0) nano-sized powders with M-type structure were synthesized by the sol-gel auto-combustion high-temperature synthesis meth
【机 构】
：
State Key Laboratory of MMCs, China,Department of Physics,Department of Metallurgy Science and Engin
论文部分内容阅读
The hexagonal BaGdxFe12-xO19 (x=0.1～1.0) nano-sized powders with M-type structure were synthesized by the sol-gel auto-combustion high-temperature synthesis method. The effects of pH of the solution, the molar ratio of nitrate/citric acid and the calcination temperature on the synthesis of the ferrites were investigated. The crystal structure, grain size, shape and magnetic properties were studied by means of XRD, TEM and vibrating sample magnetometer.The results show that under the conditions of pH 7.0 or so, mole ratio of citrate/nitrate (1～3) and calcination temperature of 850 ℃ for 1 h, M-type BaGdxFe12-xO19 ultrafine powders with a particle size of less than 100 nm can be obtained, and the coercive force reaches 430 kA*m-1 at x=1.0, which is far greater than that of barium ferrite (BaFe12O19).
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