新型低压WO3基压敏电阻掺杂及制备条件研究

研究了Ｃｏ２Ｏ３掺杂剂工艺及条件等对低压ＷＯ３基压敏电阻性能的影响，在保持ＭｎＯ２及Ｎａ２ＣＯ３含量不变的前提下，我们发现，对于ＷＯ３－ＭｎＯ２－Ｎａ２ＣＯ３系列，掺入Ａｌ２Ｏ３可以明显改善其电化学稳定，但同时也失去了非线性，而Ｃｏ２Ｏ３的掺入可以明显提高非线性，以１％（摩尔分数）的Ｃｏ２Ｏ３含量为最好，其α值约为５．５（从Ｕ１ｍＡ到Ｕ０．ｍＡ）击穿场强小于１０Ｖ／ｍｍ。最高烧结温度应不低于１１０

Studies on Fabrication Conditions and Doping of New Low Voltage WO3-based Varistor

Effects of additives and fabrication conditions on low voltage WO3-based varistor have been studied in present paper.For the system of WO3-MnO2-Na2CO3,it is found that,when the amounts of MnO2 and Na2CO3 are unchanged,Al2O3 can greatly improve the stability of sample,but at the same time sample become ohmic resister.However,doping of 1mol% Co2O3 can obviously improve the nonlinearity with nonlinear coefficient about 5.5 (from U 1mA to U 0.1mA) and breakdown field below 10V/mm.The maximum sintering temperature is between 11001150,and nonlinearity will vanish below 1050.Simple theoretical calculation and present experimental results indicate that a new nonlinear transport model different from these models for zinc oxide varistor should be established for WO3-based varistor.