采用溶胶凝胶法制备的BaFe12O19/Ni0.4Zn0.5Cu0.1Fe2O14高剩磁纳米复合颗粒(英文)

Enhanced Remanence Field for BaFe_(12)O_(19)/Ni_(0.4)Zn_(0.5)Cu_(0.1)-Fe_2O_4 Nanocomposite Particles Prepared by Sol-Gel Method

以溶胶凝胶制备的Ni_(0.4)Zn_(0.5)Cu_(0.1)Fe_(12)O_(14)纳米颗粒为软磁相和BaFe_(12)_(19)为硬磁相作为原料,以摩尔比从1:0.7到1:1.4,通过热处理后得到BaFe_(12)_(19)/Ni_(0.4)Zn_(0.5)Cu_(0.1)Fe_(12)O_(14)的纳米颗粒,经XRD炭征后,得到退火后的纳米颗粒呈现高结晶度颗粒直径大概在35 nm左右。振动样品磁强计表明摩尔比为1:1的BaFe_(12)_(19)/Ni_(0.4)Zn_(0.5)Cu_(0.1)Fe_(12)O_(14)纳米颗粒拥有高的矫顽力H_c=3761X79.6 A/m和剩余磁化强度M_r=55.1 A.m^2/kg。样品平滑的磁滞回线显示了热处理后充分发生交换耦合现象。以二结果能说明热处理后的BaFe_(12)_(19)和Ni_(0.4)Zn_(0.5)Cu_(0.1)Fe_(12)O_(14)能被用米制备具有最佳磁化性能的纳米复合颗粒。

Sol-gel method was used for consolidate powders prepared by soft Ni_(0.4)Zn_(0.5)Cu_(0.1) Fe_(12)O_(14) and hard BaFe_(12)O_(19) precursor with a ratio of 1:x(x=0.7~1.4).Subsequently,BaFe_(12)O_(19)/Ni_(0.4)Zn_(0.5)Cu_(0.1) Fe_(12)O_(14) nanocomposites were synthesized by heat treatment.XRD patterns of the annealed powders revealed that the well-crystalline powder was produced with approximately 35 nm uniform grain size.The BaFe_(12)O_(19)/Ni_(0.4)Zn_(0.5)Cu_(0.1) Fe_(12)O_(14) powder with a ratio of 1:1 reached a high coercivity H_c=3761×79.6 A/m and the remanent magnetization M_r= 55.1 A·m^2/kg.In this case,a smooth hysteresis loop implying exchange coupling was fully recovered after heat treatment.Above results illustrate that the mixture for BaFe_(12)O_(19) and Ni_(0.4)Zn_(0.5)Cu_(0.1) Fe_(12)O_(14) precursor followed by heat treatment can be used to fabricate exchange-coupled nano-composite particles with optimized magnetic properties.