Improvement of ZnO Varistor Performance

In this thesis, a detailed analysis on the basis of the principles of the sol - gel method , through a large number of experiments , study and formulation of ZnO varistors Used composite of nano additives reasonable sol - gel process , and detailed description of analysis and discussion of the all the phenomena of this process . Experimental composite nano- additives prepared using the sol - gel process , composite nano- additives mixed the Sb _{2 O 3 the SiO 2 and the main the material ZnO prepared diameter of 8.5mm, and a thickness of 1mm ZnO varistors . Morphology by scanning electron microscopy (SEM) has found that the components of the prepared grain size uniform , powder doped uniform and low porosity . By testing the electrical properties found components 8/20μs flow capacity of 2500A , 2ms square wave energy tolerance than 46J , have increased significantly compared to the traditional solid-phase synthesis process , and the the small current performance has also been significantly improved . Different sintering temperature of the sol - gel prepared ZnO varistors electrical properties at the same time , by comparison, the best conclusion sintered at 1100 ° C temperature , the electrical properties of the components . Also , electric sophisticated process of ZnO varistors 2ms square wave energy tolerance obtained a better electrical sophisticated conditions : the varistor voltage impulse voltage of approximately 2.5 times , and the impact of the number 6 times under the conditions , the energy tolerance of the resistor can be improved to some extent .}