稀土掺杂对MnZn铁氧体显微结构和磁性能的影响

Effect of rare earth doping on the microstructure and magnetic properties of MnZn ferrites sintered in different atmospheres

采用传统的氧化陶瓷法,以Fe_2O_3、ZnO、MnO_2为原料按照摩尔分数比52.5︰12︰35.5进行配料,在纯N2或4%氧分压烧结气氛中制备了分别掺杂Y^(3+)、La^(3+)、Ce^(3+)、Sm^(3+)、Gd^(3+)、Yb^(3+)的MnZn铁氧体。通过XRD、SEM、软磁交流测量装置等测试研究了样品的组织结构与磁性能。结果表明,在4%氧分压烧结气氛中制备的材料磁性能更好;掺入适量稀土能细化晶粒、优化显微结构,从而提高材料的磁性能。用于掺杂的几种稀土氧化物中,Ce_2O_3掺杂效果最好。掺杂0.03 wt%Ce_2O_3的烧结样品振幅磁导率由未掺杂时的2014提升至2756,增幅约为37%,矫顽力及功耗(测试条件:100 mT,100 kHz)分别由未掺杂时的21.03 A/m、597.5 kW/m^3降低至12.13 A/m、342.9kW/m^3,下降约43%。

MnZn ferrites doped with different amount of Y^3+,La^3+,Ce^3+,Sm^3+,Gd^3+,or Yb^3+ were prepared by conventional ceramic process,using Fe2O3 ,ZnO,and MnO2 as raw materials according to the molar fractions of 52.5:12:35.5,and sintering in pure N2 or 4% partial pressure of oxygen atmosphere.The microstructure and magnetic properties was investigated by XRD,SEM,and AC soft magnetometer.The results show that the samples sintered in 4% oxygen have better soft magnetic properties.The incorporation of appropriate amounts of rare earth ions can refine the grains,optimize the microstructure,and resultantly improve the magnetic properties.Among all rare earth oxides used in this experiment,Ce2O3 show the most advantageous effects.With 0.03 wt% Ce2O3 doping,the amplitude permeability of sintered samples increases from 2014 to 2756 with an increase of about 37 %,and the coercive force and power loss at 100 mT and 100 kHz decrease from 21.03 A/m to 12.13 A/m and 597.5 kW/m^3 to 342.9 kW/m^3 ,respectively,with a decrease of approximately 43 %.