氧化物法与溶胶-凝胶法低温共烧NiCuZn铁氧体性能比较

A Comparison in Performance of Low Temperature Co-fired NiCuZn Ferrites Prepared by both Milling Oxides Methods and Sol-Gel Methods

用机械研磨氧化物精细制粉法（简称氧化物法）和溶胶-凝胶法分别制备了成分为Ni1-α-ZnxCuα4Fe2-δO4（0．15≤α〈0．25，0．55≤x≤0.65）的低温烧结NiCuZn铁氧体超细粉。用两种方法都实现了低温共烧所要求的烧结温度Ts〈900℃。在优选配方的基础上比较了两种方法所制备的880±20℃烧结样品的起始磁导率μi、Q值、μQ积、比损耗因子tgδμ、比温度系数αμ、电阻率ρ及μi频谱等电磁性能。与溶胶．凝胶法制备的材料相比，氧化物法制备的材料有高一倍的μQ积和低一倍的比损耗因子tgδμ；高三个数量级（ρ〉10^12Ω·cm）的电阻率和相同的比温度系数（α〈×10^-6℃^-1）。最后指出：由于溶胶．凝胶法的成本高、uQ积低，氧化物法的性价比比溶胶-凝胶法的要高16-20倍。此外，溶胶-凝胶法还有不便于批量生产和环境污染等问题。

The free powders and sintered specimens of Ni1-α-ZnxCuα4Fe2-δO4（0.15≤α〈0.25,0.55≤x≤0.65） ferrites ware prepared by both oxide method and sol-gel method, Low temperature （Ts〈900℃） sintering was realized for both method, meeting the demands of co-fn-ing technique. For the same selected composition, the characteristics of specimens prepared by both methods were compared, including initial permeability μi, Q value, μQ product, tan δμ, αμ, electronic resistivity ρ and the frequency spectra of μi. The results reveal that the low temperature sintered NiCuZn ferrites prepared by milling oxides exhibit a μQ product=12.3×10^4, a tanδμ〈8.4×10^-6, and a resistivity of ρ〉10^12 Ω.cm, 2 times, 1/2 and 3 order higher than that of samples prepared by sol-gel method, respectively, and the same temperature coefficient of α〈×10^-6℃for both materials. Due to the higher cost and lower μQ product of materials prepared by sol-gel method, the ratio of cost to performance of oxide method is much lower than that of sol-gel method with a factor of 20- 16 times. The problems of sol-gel method are also pointed out in its serious environment pollution and non-convenience in manufactures.