The note of ZnO Resistors

Temperature fuse ZnO Resistors should have good thermal coupling when varistors fail (high-impedance short circuit), the heat it generates the temperature fuse fuse, varistor and separation circuit failure to ensure that the equipment Safety. When a high frequency temporary over-voltage applied to the varistor , the varistor may cause momentary short-circuit breakdown (low impedance short circuit), the temperature fuse fuse had a chance, but also may cause fire. To avoid this phenomenon may be further connected in series to each varistor fuse a high impact frequency (single frequency fuse employment at the time of aging failure may not fuse)

ZnO blocks

TGE Metal Oxide Varistors(MOV) ceramic because of its non-linear current-voltage characteristics (and non-linear coefficient is the highest of all semiconductor materials) are widely used in electronic devices [1-5]. ZnO varistors are typically the grain size, grain boundary structure control their macroscopic properties of materials. ZnO grain size and the number of grain boundary layer directly affects the breakdown voltage level. In addition, many other properties are also dependent on the polycrystalline ceramic its microstructure. In recent years, sintering and grain growth of ZnO based ceramics have been many reports of research [1-5]. People around the crystal densification and control of the sintered body sintered body grow a lot of research. According to reports, doped ZnO nano-ZnO Resistors coarse grain has a higher breakdown voltage, the greater the nonlinearity coefficient, low leakage current. And said performance increases with the amount of nano-Zinc Oxide discs [3]. Nano-sintering is the second after the emergence of nanomaterials developed a new sintering technology. The so-called nano-sintering, is to use nano-powder sintering under certain conditions, the microstructure of the phase of the nano-phase materials. Nano-sintering with the conventional sintering coarse grain compared to: (1) low sintering temperature; the nano-powder small size, high surface energy, compressed into a block material after the interface has a high energy, high in sintering interface can become the driving atomic motion force, is conducive to the interface holes shrink, annihilation vacancy clusters, thus enabling the sintering temperature is lowered.

ZnO varistor

In the preparation of nanomaterials and nano-structure, there are many people in different ways.metal oxide varistor theory These methods may be divided according to the state of the reaction medium during the preparation of two categories: solution-based liquid phase reaction of gas phase reaction based on gas phase process. Growth by gas inorganic nano materials and nano-bodies have VLS mechanism main mechanism, VS mechanism, ZnO Resistors growth (OAG) mechanism, SLS mechanism. There is now a zinc oxide fine synthesis of nanostructures with different morphologies are pulsed laser deposition (PLD), chemical vapor deposition (CVD), metal organic chemical vapor deposition (MOCVD), chemical transport method (CTM),overvoltage arrester thermal evaporation, carbothermal reduction. Solvothermal, hydrothermal method.