Zinc Oxide Varistor Composition materials and sintering methods
"Zinc oxide" (ZnO) Varistor,Its main material has a divalent element zinc (Zn) and hexavalent element oxygen (O) formed. So from the material point of view, Zinc oxide Varistor is a "II-VI oxide semiconductor". Yaxun Electronics uses alloy melt atomization oxidation method to prepare pressure-sensitive doped zinc oxide powder. By appropriate conditions, And the controllability of the particle size of the powder, Powder composition accuracy and uniformity, Doping elements and the microscopic distribution of doping elements were studied. Combined with wet addition of BiO and SbO, The coated powder in the form of an ideal powder was tested. The prepared powder was pressed and sintered, and the sintered product was tested.
ZnO-Bi2O3-TiO2-based varistor ceramic grain growth mechanism. TiO2 as the sintering temperature increases,React with Bi2O3 to form solid Bi12TiO20; 873 ~ 875 ℃ melt decomposition into solid Bi4Ti3O12; 876 ℃ -1050 ℃. Bi4Ti3O12 from solid to liquid,Liquid phase sintering ZnO can be dissolved in liquid phase Bi4Ti3O12, The grain size increases as the sintering temperature increases. When the sintering temperature is 1100 ° C or higher, Reaction with solid ZnO to form Zn2TiO4 sharp phase stone phase, Hinder the further formation of grains.
ZnO-Bi2O3-TiO2-based varistor ceramic grain growth mechanism. TiO2 as the sintering temperature increases,React with Bi2O3 to form solid Bi12TiO20; 873 ~ 875 ℃ melt decomposition into solid Bi4Ti3O12; 876 ℃ -1050 ℃. Bi4Ti3O12 from solid to liquid,Liquid phase sintering ZnO can be dissolved in liquid phase Bi4Ti3O12, The grain size increases as the sintering temperature increases. When the sintering temperature is 1100 ° C or higher, Reaction with solid ZnO to form Zn2TiO4 sharp phase stone phase, Hinder the further formation of grains.