稀土掺杂氧化锌压敏瓷的研究进展

Research Progress of Rear Earth Doped ZnO-based Varistor Ceramics

综述了近年来稀土掺杂氧化锌压敏瓷中的研究进展。掺杂稀土氧化物可明显的减小ZnO晶粒尺寸,使晶粒尺寸分布均匀;其中掺杂Y2O3可使ZnO-Bi2O3系压敏瓷晶粒尺寸由11.3μm降到5.4μm,掺杂Er2O3使晶粒尺寸由1.60μm减小到1.06μm。显著提高了ZnO压敏瓷的电位梯度、降低了漏电流。其中在ZnO-Bi2O3系压敏瓷中掺杂Y2O3,可获得电位梯度约为270 V/mm、漏电流为3μA、压比为1.66的电阻片,在ZnO-PrA6O11系压敏瓷中掺杂Er2O3,电位梯度可提高到416.3 V/mm,漏电流从28.2μA降低到9.8μA。

The research progress of rear earth doped ZnO-based varistor ceramics was reviewed. It can improves microstructure, decreased ZnO grain size and homogenizing the grain size distribution. Y2O3 doping makes the ZnO-Bi2O3 varistor grain size decreased from 11.3 μm to 5.4 μm, Er2O3 doping makes the grain size decreased from 1.60 μm to 1.06 μm. The voltage gradient of the ZnO-based varistor is enhanced and the leakage current decreased. Varistor of ZnO-Bi2O3 based ceramics with Y2O3 doping has voltage gradient of about 270 V/mm, leakage current of 3 μA and voltage ratio of 1.66. Doping Er2O3 into ZnO-PrA6O11 based varistor may obtain enhanced voltage gradient of 416.3 V / mm and reduced leakage current from 28.2 μA to 9.8 μA.