掺杂氧化钇氧化镍对氧化锌电阻片特性的影响

The Influences of the Ni-oxides and Y-oxides Dopant on Electrical Characteristic of ZnO Varistor

通过掺杂氧化镍、氧化钇,对改善ZnO压敏电阻片电气特性进行了系统研究;分析和讨论了电阻片的电位梯度E、泄漏电流IL、压比Ki、方波、大电流冲击所引起的变化以及老化试验等;掺杂后,不仅提高了电阻片的电位梯度,同时还提高了其能量吸收能力;特别是钇掺杂处于晶界上,抑制晶粒长大,使晶界电压降低,大约为2.2V,是传统电阻片晶界电压的70%。研究获得了电位梯度达260V/mm,方波为800A,能量吸收能力达到300J/cm3的直径为56mm、厚度为9mm的ZnO压敏电阻片。

The electrical characteristics of ZnO-Bi2O3-based varistor doped with Ni-oxides and Yoxides were systemically studied in this paper. The influences of the two kind of additive on the reference voltage gradient E, the leakage current Il, the voltage ratio Ki, the rectangular wave current withstanding capability, the high-lightning current （4/10） withstanding capability and the long-term stability property of the vatistor were fully investigated and then discussed. It is believed that the Ni and Yoxides dopant have increased the reference voltage gradient as well as the energy absorption capability of the varistor. The Y-oxides which distribute along the ZnO grain boundaries have inhibited the growth of the ZnO grains in the sintering process and decreased the voltage across grain boundaries each, which is approximately 2.2V, about 70% of that of the conventional ZnO-Bi2O3-based varistor. A new kind of Ф56×9mm varistor was developed and its reference voltage gradient, rectangular wave current withstand capability, energy absorption capability spectively. raised to 260V/mm, 800A, and nearly 300J/cm^3 respectively.