Nb_2O_5掺杂及TiO_2压敏陶瓷埋烧工艺的研究

The effects of burying sintering process and Nb_2O_5-doped amounts on the electric properties of TiO_2 varistor ceramic

通过微结构分析、I V特性及复阻抗频谱的测量 ,比较了埋烧和传统的裸烧工艺对于Nb5+ 掺杂的TiO2压敏陶瓷材料的压敏电压和非线性系数的影响 ,结果表明掩埋法烧结可以降低该类陶瓷材料的压敏电压和非线性系数 ;考察了Nb2 O5掺杂的作用 ,表明Nb5+ 固溶于TiO2 中取代Ti4+ 使晶粒半导化 .Nb2 O5掺杂量对TiO2 压敏陶瓷的I V特性和微观结构都会有影响作用 ,适量Nb5+

By microstructure analysis, I-V characteristic and c om plex impedance spectra measurement, the effects of burying sintering were compar ed with those of the traditional sintering process on breakthrough-voltage and nonlinear exponent of Nb 5+ -doped TiO 2-based ceramic materials. The res ults showed that the burying sintering method could make the breakthrough-volta ge and nonlinear exponent smaller. The roles of Nb 2O 5 dopant in the TiO 2 v aristor ceramic were also investigated. The results revealed that Nb 5+ dis solved into TiO 2 grains to substitute Ti 4+ for enhancing ceramic semicon ductivity behavior. The amount of Nb 2O 5 dopant influenced I-V characterist ic and microstructure of the TiO 2 varistor ceramic. The proper amount of Nb 2 O 5 dopant could make grain growing.