Sno with high nonlinearity, low residual voltage and large current capacity for power system transmission 2 The preparation method of varistor

Abstract

A kind of SnO with high nonlinearity, low residual voltage and large current capacity for power system transmission 2 The preparation method of the varistor, the composition of the varistor includes SnO 2 , Co 3 O 4 , Cr 2 O 3 , Ni 2 O 3 , Sb 2 O 5 , Ta 2 O 5 , whose preparation steps include SnO 2 The main slurry preparation steps, Co 3 O 4 , Cr 2 O 3 , Ni 2 O 3 , Sb 2 O 5 , Ta 2 O 5 The auxiliary slurry preparation step, the main slurry, the mixing step of the auxiliary slurry, the molding step, the degumming step, and the sintering step, the SnO 2 The main slurry preparation steps, Co 3 O 4 , Cr 2 O 3 , Ni 2 O 3 , Sb 2 O 5 , Ta 2 O 5 The auxiliary slurry preparation step, the main slurry, the mixing step of the auxiliary slurry, the molding step, the degumming step, and the sintering step are performed in sequence. Its beneficial effects are: increased SnO 2 The ability of the varistor to leak large currents achieves the purpose of enhancing its nonlinear coefficient and current capacity; the residual voltage ratio is suppressed to the lowest level, which is better than the results measured by a single doped Ta or Sb element , the aging stability is stronger.

Description

technical field [0001] The invention relates to the field of electrical materials, in particular to a SnO with high nonlinearity, low residual voltage and large current capacity for power system transmission. 2 A method of making a varistor. Background technique [0002] A varistor is an electronic component whose conductive properties change with the change of the applied voltage. When the voltage applied across the varistor is greater than the varistor's varistor voltage, the conductance of the varistor will increase infinitely. When the applied voltage is lower than the varistor voltage of the varistor, the varistor exhibits infinitely small conductance, which is quite in the disconnected state. This non-ohmic characteristic of a varistor is similar to that of two back-to-back Zener diodes, except that the varistor has no polarity. Not only that, the overvoltage that the varistor can withstand can range from a few volts to tens of thousands of volts, the impact current...

AI Technical Summary

Problems solved by technology

Currently SnO 2 The reasons for the poor electrical characteristics of varistors come from two aspects: First, in terms of formulation, according to the situation reported in the literature, the doping of elements with the same function in the formulation is too single, resulting in the grain boundary in the prepared sample. The formation effect is poor, making the prepared SnO 2 The electrical characteristics of varistors are relatively poor, and the present invention introduces binary donor doping at the same time, avoiding the defect of single donor element doping; two in terms of technology: currently about SnO 2 In the preparation process of pressure-sensitive ceramics, SnO is used in the abrasive stage 2 The main material and the auxiliary additives are ball milled together, so the problem is that they sink in the ball mill tank, while the fine material continues to be ball milled. After the powder prepared in this way is pressed and sintered, the result shown is The microstructure is disorganized and the number of pores is large

Therefore, SnO with high nonlinearity, low residual pressure and large flow capacity has not yet been produced. 2 Varistor Valve