交变磁场诱导自蔓延法制备Mn-Zn铁氧体及其磁性能

采用交变磁场诱导溶胶凝胶自蔓延法制备Mn0.6Zn0.4Fe2O4型纳米粉体,利用X射线衍射仪、扫描电镜和超导量子干涉仪对不同磁感应强度下制备粉体的物相、形貌和磁性能进行了表征。结果表明:交变磁场可以促进自蔓延反应的燃烧过程,但并不改变燃烧产物的相结构。随磁感应强度增加,Mn0.6Zn0.4Fe2O4粉体的粒径和矫顽力逐渐减小,饱和磁化强度逐渐增加。当磁感应强度为0.25T时,相比未加入交变磁场制备的粉体,Mn0.6Zn0.4Fe2O4粉体的矫顽力下降96%,达到278.6A/m,饱和磁化强度提高了500%,达到49.4A·m/kg。

PREPARATION AND MAGNETIC PROPERTIES OF Mn-Zn FERRITE BY ALTERING MAGNETIC FIELD INDUCED SHS METHOD

Mn-Zn ferrite (Mn0.6Zn0.4Fe2O4) nanoparticles were prepared by altering magnetic field induced sol-gel self-propagating high-temperature synthesis (SHS) method. The phase structure, morphology and magnetic property of the particles synthesized at different magnetic flux densities were characterized by X-ray diffractometer, scanning electron microscope and the superconducting quantum interference device. The results show that the combustion process of SHS can be accelerated by the altering magnetic field, but the phase structure of the ferrite powder does not be changed. With the increase of magnetic flux density, the particle size and coercivity of Mn0.6Zn0.4Fe2O4 particles decrease gradually, and the saturation magnetization increases synchronously. When magnetic flux density is 0.25 T, the coercivity of the Mn0.6Zn0.4Fe2O4 powder is 278.6 A/m which decreases 96%, and the saturation magnetiza-tion is 49.4 A·m/kg which increases 500% compared to those of particles without altering magnetic field respectively.