Synthesis of Pr6O11 and Y2O3 Doped Zinc Varistors by High Energy Milling.

High voltage zinc varistors were synthesized by high-energy milling with Pr6O11 and Y2O3 doped ZnO-Bi2O3 system as raw materials. The effects of high-energy milling on the microstructures, electrical properties and densities of samples were investigated in detail. The results show that high-energy milling make the as-prepared varistors have refined and homogeneous microstructures, which result in improving their electrical properties. The optimal prepared samples were obtained by milling for 7.5 hours and sintering at 1100°C, which exhibited varistor voltage (V1mA) of about 533 V/mm, non linear coefficient (α) reaching 36 and leakage current (IL) of 2.96 μA. [ABSTRACT FROM AUTHOR]