CaCu_3Ti_4O_(12)/NiCuZn铁氧体基磁电复合材料研究

Investigations on CaCu_3 Ti_4 O_(12)/NiCuZn Magnetoelectric Composite Materials

将CCTO(CaCu3Ti4O12)与NiCuZn铁氧体进行复合,系统地研究了组分变化对这种新型磁电复合材料的烧结性能、晶相结构、显微结构和磁电性能的影响。随后,为了实现复合材料的低温烧结以及综合考虑复相陶瓷的磁电性能,选取80%(质量分数,下同)NiCuZn铁氧体/20%CCTO组分,以BBSZ(Bi2O3-H3BO3-SiO2-ZnO)玻璃作为助熔剂,研究了CCTO/NiCuZn铁氧体基复合材料的烧结行为和磁电性能。结果表明,掺杂BBSZ后,900℃下烧结的所有样品的密度均达到了复相陶瓷理论密度的95%,且复相陶瓷的介电常数和磁导率在1～30 MHz范围内均不依赖于频率的变化。在10 MHz的频率下,当BBSZ的含量从0增加到3%时,复相陶瓷磁导率μ从13.2增加到47.9,磁损耗tanδμ从0.022下降到0.017,同时,样品的谐振频率从109Hz左右移动到3.2×108Hz。相应地,复相陶瓷的介电常数ε从9.2增加到16,介电损耗tanδε从0.069下降到0.012。这一优异的整体性能使其有望实际应用。

in this paper, CCTO/NiCuZn ferrite composite materials were synthesized by the the conventional ceramic processing. The effect of composition on the sintering properties, crystalline-phase structure, microstructure, magnetic and dielectric properties of the new ferrite-dielectric composite materials had been investigated systematically. To realize low temperature sintering of the composite materials and by a comprehensive evaluation of both magnetic and dielectric properties, we chose the composition of 80% NiCuZn（mass fraction） ferrite/20 wt% CCTO in here. Then, BBSZ glass was considered as an additive and its effect on sintering behavior, magnetic and dielectric properties of CCTO/NiCuZn ferrite composite materials were studied. The results showed that the density of all BBSZ-doped samples sintered at 900 ℃ had reached 95 % of theoretical density. The dielectric constant and permeability of composites showed weak frequency dependence in a frequency range from 1 MHz to 30 MHz. At 10 MHz, as the BBSZ content increased from 0 to 3% （mass fraction）, the permeability μ of composites increased from 13.2 to 47.9, and the magnetic loss tanδμ decreased from 0. 022 to 0. 017. Meanwhile, the resonant frequency of composites decreased from 10^9 Hz to 3.2×10^8Hz. Correspondingly, the dielectric constant ε of composites increased from 9.2 to 16, and the dielectric loss tanδε, decreased from 0. 069 to 0. 012. The excellent whole performances of composites are expected to be able to promote practical applications.