高能球磨法制备氧化锌压敏电阻的低温烧结

LOW-TEMPERATURE SINTERING OF ZINC OXIDE-BASED VARISTORS PREPARED BY A HIGH-ENERGY BALL MILL

粗晶氧化锌(ZnO)混合粉经5h高能球磨,其晶粒尺寸减小至43nm。高能球磨增强了混合粉的烧结性,使其烧结温度降至800℃。扫描电镜及各个烧结温度下电性能和密度的实验结果证明:800℃烧结的压敏电阻具有最大的密度和良好的电性能,其相对密度达98.94%,电位梯度为1528V/mm,漏电流为20μA,非线性系数为15.4,晶粒尺寸为1.4μm。

Zinc oxide （ZnO） grain size was reduced to about 43 nm after 5 h, high-energy ball milling （HEBM） of coarse ZnO-based varistor mixed powders. The HEBM technique enhances the sinterability of ZnO-based varistor mixed powders and can reduce the sintering temperature to 800 ℃, at which temperature ceramic exhibits the highest density and good electrical properties, with the relative density of 98.94%, voltage gradient of 1 528 V/ram, leakage current of 20 μA, non-linear coefficient of 15.4, and crystalline grain size of 1.4 μm. This was evidenced by the scanning electron microscope and the experimental results of electrical properties and density at various sintering temperatures.