摘要
通过实验对三氧化二铟掺杂的SnO2·Co2O3·Nb2O5压敏电阻的性能进行了研究。所用样品是在1350℃下烧结1h而制成的。实验发现所有样品都具有很高的致密度(相对密度不小于97.6%),这主要是由于Co2O3影响陶瓷的烧结过程造成的。当In2O3掺杂量为0.05mol%时,压敏电阻具有最高的非线性系数(α=19.3)。随着In2O3掺杂量的从0.00mol%增加至0.10mol%,非线性电场强度从213V/mm增加至815V/mm,而平均晶粒尺寸从6.6μm减小至4.9μm,非线性电场的增加与平均晶粒尺寸的减小密切相关;样品的相对介电常数也从2307减小至153,这归因于平均晶粒尺寸与势垒厚度比的减小。
An investigation on the properties of In_2O_3-doped SnO_2·Co_2O_3·Nb_2O_5 varistors was made by experiments. The varistor samples were sintered at 1350℃ for 1h. It was observed that all the samples exhibit high densifications (relative density is no less than 97.6%), mainly due to the influence of Co_2O_3 on the sintering process. It was found that nonlinear coefficient presents a peak of α =19.3 for the concentration of 0.05mol% In_2O_3, the average grain size decreases from 6.6μm to 4.9μm, the breakdown electrical field increases from 213V/mm to 815V/mm and relative electrical permittivity decreases from 2307 to 153 with increasing In_2O_3 from 0.00mol% to 0.10mol%. The increase of breakdown electrical field with increasing In_2O_3 concentration was mainly attributed to the decrease of grain size. The reason why the permittivity decreases with increasing In_2O_3 concentration was originated from the ratio of the grain size to the barrier width.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2004年第1期71-73,76,共4页
Journal of Functional Materials
基金
国家自然科学基金资助项目(50072013)
