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用机械合金化方法制备了各向同性Ｍ型ＳｒＦｅ１２Ｏ１９磁性粉末，系统地研究了球磨条件对磁性的影响。结果表明，在相结构转变上，低温退火与长时间球磨起着相似的作用。当样品在７５～８００℃退火处理时，饱和磁化强度Ｍｓ比矫顽力Ｈｃ受球磨条件影响更明显。采用高能球磨制备的各向同性样品，在球磨３０ｈ后于１０００℃退火处理，其饱和和磁化强度和矫顽力可分别达到３００ｋＡ／ｍ和４４８ｋＡ／ｍ。延长热处理时间对磁性影响不大。退磁曲线表明矫顽力场相应于磁化过程中的钉扎和成核场。
An isotropic M-type SrFe12O19 magnetic powder was prepared by mechanical alloying. The influence of milling conditions on magnetic properties was studied systematically. The results show that the low-temperature annealing plays a similar role as the long-time milling in phase transformation. When the sample is annealed at 75 ~ 800 ℃, the saturation magnetization Ms is more obvious than the coercivity Hc under ball milling conditions. The isotropic samples prepared by high energy ball milling annealed at 1000 ℃ for 30h, the saturation and magnetization and coercive force can reach 300kA / m and 448kA / m, respectively. Extending the heat treatment time has little effect on magnetism. Demagnetization curves show that the coercive force field corresponds to the pinning and nucleation fields during magnetization.