CN115124337A - Zinc oxide pressure-sensitive ceramic, preparation method and application thereof - Google Patents

Zinc oxide pressure-sensitive ceramic, preparation method and application thereof Download PDF

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CN115124337A
CN115124337A CN202210693087.XA CN202210693087A CN115124337A CN 115124337 A CN115124337 A CN 115124337A CN 202210693087 A CN202210693087 A CN 202210693087A CN 115124337 A CN115124337 A CN 115124337A
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pressure
tio
sensitive ceramic
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徐东
石梦阳
熊海琴
刘娟
左如忠
程亚芳
钟素娟
郝庆乐
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Anhui Polytechnic University
Anhui University of Technology AHUT
China Innovation Academy of Intelligent Equipment Co Ltd CIAIE
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Anhui Polytechnic University
Anhui University of Technology AHUT
China Innovation Academy of Intelligent Equipment Co Ltd CIAIE
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Abstract

The invention relates to the technical field of ceramic preparation, in particular to a zinc oxide pressure-sensitive ceramic, a preparation method and application thereof, and ZnO and Bi are mixed 2 O 3 、Sb 2 O 3 、Ni 2 O 3 、Co 3 O 4 、MnO 2 、Al(NO 3 ) 3 、TiO 2 Mixing the powder in deionized water with ZrO 2 Ball-milling the medium at the speed of 200r/min for 12 hours, and drying at the temperature of 80 ℃ for 24 hours; mixing the obtained dry powder with a binder, and pressing the mixture into a green body under the pressure of 310 MPa; heating the obtained green body to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder; sintering the obtained green body without the binder to 1200-1300 ℃ at the heating rate of 5 ℃/min, preserving the heat for 90min, and then cooling to room temperature to obtain the low-pressure-sensitive ceramicThe zinc oxide pressure-sensitive ceramic solves the problems that the existing preparation method of the low-pressure-sensitive ceramic is difficult and the performance of the obtained low-pressure-sensitive ceramic is poor.

Description

Zinc oxide pressure-sensitive ceramic, preparation method and application thereof
Technical Field
The invention relates to the technical field of ceramic preparation, in particular to a zinc oxide pressure-sensitive ceramic, a preparation method and application thereof.
Background
ZnO voltage sensitive ceramics are commonly used in electronic and industrial equipment to absorb transient surges and protect power systems. The nonlinear characteristic is the most important characteristic of the varistor and is expressed by the formula I ═ KV α, where I is the current, K is a constant, V is the voltage, and α is a nonlinear coefficient. The higher the non-linear coefficient alpha is, the better the pressure sensitive performance is, the non-linear current-voltage characteristic of the ZnO pressure sensitive ceramic is related to the grain boundary barrier and the resistance, and the excellent non-linear characteristic can be achieved by adding some special additives, such as Bi 2 O 3 And V 2 O 5 And the like, the additive is segregated in a grain boundary, a grain boundary barrier is generated, and nonlinear characteristics are generated, so that the ZnO pressure-sensitive ceramic for high pressure is mostly researched, and the ZnO pressure-sensitive ceramic suitable for low pressure occasions is rarely reported. In recent years, electronic equipment is miniaturized, the voltage withstanding value of electronic components in a circuit is reduced, the circuit is easy to be damaged due to overvoltage operation, and low-voltage-sensitive ceramic can absorb the interiorAnd external surges to protect power electronic circuits.
The preparation of the low-voltage-sensitive ceramic can be realized by reducing the thickness of a ceramic chip, reducing the breakdown voltage of a single crystal boundary layer in a ZnO voltage-sensitive resistor ceramic chip or increasing the size of ZnO crystal grains, the thickness is usually reduced by preparing a thin film or a multilayer ceramic chip, and the ZnO-Pr is prepared by a radio frequency sputtering method by means of Horio N and the like 6 O 11 The double-layer film has a thickness of 600nm-400nm, a voltage-dependent voltage of 10V and a nonlinear coefficient of 10. In the prior art, ZnO-V is prepared 2 O 5 The multilayer chip voltage-sensitive resistor is prepared by low-temperature co-firing with an Ag inner electrode, although the voltage can be effectively reduced by reducing the thickness, the thin ZnO ceramic chip is difficult to prepare and has poor performance due to small volume; the theoretical basis of the method for reducing the voltage-dependent voltage by reducing the breakdown voltage of the single crystal boundary layer is the double Schottky barrier model (DSB) and Gupta&Carlson defect model. It has also been proposed to increase the annealing temperature and time, increase the liquid phase to promote grain growth, and reduce the voltage-dependent voltage, but the process is complicated and the cost is high; therefore, we usually adopt the effect of adding a special dopant to increase the average grain size of ZnO to achieve low pressure. Flash firing, which has recently appeared, is disadvantageous in that it is not suitable for the production of low-pressure varistor ceramics because of the high temperature rising rate and the short sintering time, and the growth of crystal grains is suppressed to increase the voltage gradient, although a high nonlinear coefficient can be obtained.
In view of the above-mentioned drawbacks, the inventors of the present invention have finally obtained the present invention through a long period of research and practice.
Disclosure of Invention
The invention aims to solve the problems that the existing preparation method of low-pressure-sensitive ceramic is difficult and the obtained low-pressure-sensitive ceramic has poor performance, and provides zinc oxide pressure-sensitive ceramic, a preparation method and application thereof.
In order to realize the aim, the invention discloses a preparation method of zinc oxide pressure-sensitive ceramic, which comprises the following steps:
s1: ZnO and Bi are mixed 2 O 3 、Sb 2 O 3 、Ni 2 O 3 、Co 3 O 4 、MnO 2 、Al(NO 3 ) 3 、TiO 2 Mixing the powder in deionized water with ZrO 2 Ball milling the medium at the speed of 200r/min for 12 hours, and drying at 80 ℃ for 24 hours;
s2: mixing the dry powder obtained in step S1 with a binder, and then pressing into a green compact at 310 MPa;
s3: heating the green body obtained in the step S2 to 600 ℃ at the heating rate of 2 ℃/min for 2h, and removing the binder;
s4: and (4) sintering the green body without the binder obtained in the step S3 to 1200-1300 ℃ at the heating rate of 5 ℃/min, preserving the heat for 90min, and then cooling to room temperature.
ZnO and Bi in the step S1 2 O 3 、Sb 2 O 3 、Ni 2 O 3 、Co 3 O 4 、MnO 2 、Al(NO 3 ) 3 、TiO 2 The powder comprises 90-95 parts of ZnO by mole; bi 2 O 3 0.5-2 parts; sb 2 O 3 0.3-1 part; ni 2 O 3 0.2-1.5 parts; co 3 O 4 0.3-1.5 parts; MnO 2 0.3-1.5 parts; al (NO) 3 ) 3 0-0.5 parts; TiO 2 2 0-2 parts of a solvent;
the diameter of the green compact in step S2 is 13 mm.
When the temperature is reduced in the step S4, the temperature is reduced to 900 ℃ at the speed of 1 ℃/min, then the temperature is reduced to 600 ℃ at the speed of 3 ℃/min, and finally the temperature is reduced to the room temperature at the speed of 1 ℃/min.
The invention also discloses the zinc oxide voltage-sensitive ceramic prepared by the preparation method and application of the zinc oxide voltage-sensitive ceramic in electronic components by absorbing surge.
By doping with TiO in the present application 2 ，TiO 2 And Bi 2 O 3 Reaction to produce Bi 4 Ti 3 O 12 The liquid phase increases the solubility of ZnO in the Bi-rich liquid phase, is easy to promote the growth of crystal grains, reduces the number of crystal boundaries, reduces potential gradient and achieves the aim of preparing low-pressure-sensitive ceramic; while TiO is in a certain range 2 The nonlinear coefficient is increased, so that the low potential gradient is obtainedWhile having a high non-linear coefficient.
Compared with the prior art, the invention has the beneficial effects that: the invention utilizes doping TiO with different contents 2 Preparing ZnO-Bi 2 O 3 Based on low-voltage pressure-sensitive ceramic, all prepared samples have uniform microstructures along with TiO 2 The content is increased, the crystal grains are slightly increased, and the voltage gradient is generally in a descending trend. All the component samples have pressure sensitive properties, of which TiO 2 When the amount of (A) is 0.5 mol%, the performance is best, the voltage gradient is 178V/mm, the nonlinear coefficient is 28.9, and the leakage current is 0.94. mu.A. Research shows that TiO is added 2 Then, enough Bi-rich liquid phase is provided, the solubility of ZnO is increased, and the growth of crystal grains is promoted. The ionic radius of Ti is similar to that of Zn but slightly smaller than that of Zn, so that when Ti enters ZnO grains, lattice distortion is caused, the solid-phase mass transfer process is promoted, and sintering is further promoted.
Drawings
FIG. 1 shows TiO in examples 4, 5, 6, 7 and 8 2 XRD of ZnO-doped pressure sensitive ceramic;
FIG. 2 shows TiO in example 4 2 SEM of ZnO-doped voltage sensitive ceramic;
FIG. 3 shows TiO in example 5 2 SEM of ZnO-doped voltage sensitive ceramic;
FIG. 4 shows TiO in example 6 2 SEM of ZnO-doped voltage-sensitive ceramic;
FIG. 5 shows TiO in example 7 2 SEM of ZnO-doped voltage sensitive ceramic;
FIG. 6 shows TiO in example 8 2 SEM of ZnO-doped voltage sensitive ceramic;
FIG. 7 shows TiO examples of all examples 2 Relative compactness of the ZnO-doped pressure sensitive ceramic;
FIG. 8 shows TiO in examples 4, 5, 6, 7 and 8 2 E-J curve of ZnO-doped pressure sensitive ceramic;
FIG. 9 is an ideal Nyquist impedance diagram (Cole-Cole diagram) and a classical equivalent circuit diagram of a ZnO voltage-sensitive ceramic;
FIG. 10 shows TiO in examples 4, 5, 6, 7 and 8 2 Impedance spectrum of the doped ZnO voltage-sensitive ceramic;
Detailed Description
The above and further features and advantages of the present invention are described in more detail below with reference to the accompanying drawings.
TABLE 1 formulation of ceramic powders for each of the examples and comparative examples
Raw materials ZnO Bi 2 O 3 Sb 2 O 3 Ni 2 O 3 Co 3 O 4 MnO 2 Al(NO 3 ) 3 TiO 2
Example 1 90 2 1 1.5 1.5 1.5 0.5 2
Example 2 95 0.5 0.3 0.2 0.9 1 0.1 2
Example 3 95.77 0.7 0.5 0.43 0.3 0.3 0 2
Example 4 97.38 0.7 0.5 0.43 0.49 0.49 0.01 0
Example 5 96.88 0.7 0.5 0.43 0.49 0.49 0.01 0.5
Example 6 96.38 0.7 0.5 0.43 0.49 0.49 0.01 1
Example 7 95.88 0.7 0.5 0.43 0.49 0.49 0.01 1.5
Example 8 95.38 0.7 0.5 0.43 0.49 0.49 0.01 2
Example 1
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material comprises 90 parts of ZnO and 2 parts of Bi by mole ratio 2 O 3 1 part of Sb 2 O 3 1.5 parts of Ni 2 O 3 1.5 parts of Co 3 O 4 1.5 parts of MnO 2 0.5 part of Al (NO) 3 ) 3 2 parts of TiO 2 ；
Step two: ball milling is carried out for 12h at the speed of 200r/min, and the mixture is put into an oven at the temperature of 80 ℃ for drying for 24 h. The powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed at a pressure of 310MPa into green bodies with a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering at a heating rate of 5 ℃/min to 1200 ℃, preserving heat for 90min, cooling to 900 ℃ at a rate of 1 ℃/min, cooling to 600 ℃ at a rate of 3 ℃/min, and finally cooling to room temperature at a rate of 1 ℃/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Example 2
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material comprises 95 parts of ZnO and 0.5 part of Bi by mole ratio 2 O 3 0.3 part of Sb 2 O 3 0.2 part of Ni 2 O 3 0.9 part of Co 3 O 4 1 part of MnO 2 0.1 part of Al (NO) 3 ) 3 2 parts of TiO 2 ；
Step two: ball milling is carried out for 12h at the speed of 200r/min, and the mixture is put into an oven with the temperature of 80 ℃ for drying for 24 h. The powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed at a pressure of 310MPa into green bodies with a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1250 ℃ at the heating rate of 5 ℃/min and preserving heat for 90 min. And cooling to 900 ℃ at a speed of 1 ℃/min, then cooling to 600 ℃ at a speed of 3 ℃/min, and finally cooling to room temperature at a speed of 1 ℃/min to obtain the zinc oxide pressure-sensitive ceramic of the embodiment.
Example 3
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material comprises 95.77 parts of ZnO and 0.7 part of Bi in molar ratio 2 O 3 0.5 parts of Sb 2 O 3 0.43 part of Ni 2 O 3 0.3 part of Co 3 O 4 0.3 part of MnO 2 2 parts of TiO 2 ；
Step two: ball-milling at a speed of 200r/min for 12h, drying in an oven at 80 ℃ for 24h, mixing the powder with 5 wt.% of polyvinyl alcohol (PVA), uniaxially compressing under a pressure of 310MPa to form a green body with a diameter of 13mm, heating to 600 ℃ at a heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1300 ℃ at the heating rate of 5 ℃/min, preserving heat for 90min, cooling to 900 ℃ at 1 ℃/min, cooling to 600 ℃ at 3 ℃/min, and finally cooling to room temperature at 1 ℃/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Example 4
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material comprises, in mole ratio, 97.38 parts of ZnO and 0.7 part of Bi 2 O 3 0.5 parts of Sb 2 O 3 0.43 parts of Ni 2 O 3 0.49 parts of Co 3 O 4 0.49 parts of MnO 2 0.01 part of Al (NO) 3 ) 3 ；
Step two: ball milling is carried out for 12h at the speed of 200r/min, and the mixture is put into an oven with the temperature of 80 ℃ for drying for 24 h. The powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed at a pressure of 310MPa into green bodies with a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1250 ℃ at the heating rate of 5 ℃/min and preserving heat for 90 min. Cooling to 900 deg.C at 1 deg.C/min, cooling to 600 deg.C at 3 deg.C/min, and cooling to room temperature at 1 deg.C/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Example 5
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material was composed of 96.88 parts of ZnO and 0.7 part of Bi in molar ratio 2 O 3 0.5 parts of Sb 2 O 3 0.43 part of Ni 2 O 3 0.49 parts of Co 3 O 4 0.49 parts of MnO 2 0.01 part of Al (NO) 3 ) 3 (ii) a 0.5 part of TiO 2 ；
Step two: ball milling was carried out at a speed of 200r/min for 12h, drying was carried out in an oven at 80 ℃ for 24h, the powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed under a pressure of 310MPa into green bodies having a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1250 ℃ at the heating rate of 5 ℃/min, preserving heat for 90min, cooling to 900 ℃ at 1 ℃/min, cooling to 600 ℃ at 3 ℃/min, and finally cooling to room temperature at 1 ℃/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Example 6
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material comprises 96.38 parts of ZnO and 0.7 part of Bi by mole ratio 2 O 3 0.5 parts of Sb 2 O 3 0.43 parts of Ni 2 O 3 0.49 parts of Co 3 O 4 0.49 parts of MnO 2 0.01 part of Al (NO) 3 ) 3 (ii) a 1 part of TiO 2 ；
Step two: ball milling is carried out for 12h at the speed of 200r/min, and the mixture is put into an oven with the temperature of 80 ℃ for drying for 24 h. The powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed at a pressure of 310MPa into green bodies with a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1250 ℃ at the heating rate of 5 ℃/min and preserving the temperature for 90 minutes. Cooling to 900 deg.C at 1 deg.C/min, cooling to 600 deg.C at 3 deg.C/min, and cooling to room temperature at 1 deg.C/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Example 7
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material was composed of 95.88 parts of ZnO and 0.7 part of Bi in molar ratio 2 O 3 0.5 parts of Sb 2 O 3 0.43 parts of Ni 2 O 3 0.49 parts of Co 3 O 4 0.49 parts of MnO 2 0.01 part of Al (NO) 3 ) 3 (ii) a 1.5 parts of TiO 2 ；
Step two: ball milling was carried out at a speed of 200r/min for 12h, drying was carried out in an oven at 80 ℃ for 24h, the powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed under a pressure of 310MPa into green bodies having a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1250 ℃ at the heating rate of 5 ℃/min and preserving heat for 90 min. Cooling to 900 deg.C at 1 deg.C/min, cooling to 600 deg.C at 3 deg.C/min, and cooling to room temperature at 1 deg.C/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Example 8
A preparation method of zinc oxide pressure-sensitive ceramic comprises the following steps:
the method comprises the following steps: according to the formulation of the ceramic powder of this example shown in Table 1, the ceramic powder material comprises 95.38 parts of ZnO and 0.7 part of Bi by mole ratio 2 O 3 0.5 parts of Sb 2 O 3 0.43 parts of Ni 2 O 3 0.49 parts of Co 3 O 4 0.49 parts of MnO 2 0.01 part of Al (NO) 3 ) 3 (ii) a 2 parts of TiO 2 ；
Step two: ball milling was carried out at a speed of 200r/min for 12h, drying was carried out in an oven at 80 ℃ for 24h, the powder was mixed with 5 wt.% polyvinyl alcohol (PVA) and uniaxially compressed under a pressure of 310MPa into green bodies having a diameter of 13 mm. Heating to 600 ℃ at the heating rate of 2 ℃/min, heating for 2h, and removing the binder;
step three: sintering to 1250 ℃ at the heating rate of 5 ℃/min and preserving heat for 90 min. Cooling to 900 deg.C at 1 deg.C/min, cooling to 600 deg.C at 3 deg.C/min, and cooling to room temperature at 1 deg.C/min; the zinc oxide pressure sensitive ceramic of this example was obtained.
Performance testing
The following performance tests were performed on the zinc oxide varistor ceramics obtained in the examples, respectively:
(1) the electrode and the pressure-sensitive performance detection comprise a nonlinear coefficient alpha and a voltage gradient V T Leakage current I L
The examination results are shown in table 2:
TABLE 2 pressure sensitive Property test data for each example
Non-linear coefficient alpha Potential gradient V T (V/mm) Leakage current I L (μA)
Example 1 29.7 335 0.78
Example 2 23.1 247 1.40
Example 3 25.4 384 1.72
Example 4 17.3 200 0.89
Example 5 28.9 178 0.94
Example 6 21.0 188 5.30
Example 7 10.0 165 62.60
Example 8 9.0 126 83.90
As is clear from Table 2, examples 4 to 8 have smaller potential gradients than examples 1 to 3, and are more advantageous for achieving low voltage. In examples 4 to 8, with TiO 2 Increase of doping content and overall appearance of voltage gradientReduced tendency, mainly due to doped TiO 2 Part of and Bi 2 O 3 Bi produced by the reaction 4 Ti 3 O 12 The liquid phase increases the solubility of ZnO in the Bi-rich liquid phase, thereby promoting the growth of crystal grains and reducing the number of crystal boundaries. The relation is E 1mA ＝U gb D, wherein E 1mA To breakdown voltage, U gb The grain boundary breakdown voltage and d is the grain size. In example 6, the voltage gradient was slightly increased, probably due to Zn formed by reaction with ZnO 2 TiO 4 The spinel phase is abundant, and the spinel phase at the grain boundary suppresses grain growth, and slightly increases the voltage gradient. The non-linear coefficient shows a tendency to increase first and then decrease, wherein the non-linearity of example 5 is optimally 28.9. This is because the nonlinear coefficient is generally related to the grain boundary barrier, and generally a high grain boundary barrier corresponds to a high nonlinear coefficient, and a low grain boundary barrier nonlinear coefficient is also low. Due to partial TiO 2 Segregation occurs at grain boundaries, and the nonlinear coefficient is increased by increasing the grain boundary barrier. When TiO is present 2 When the content continues to increase, TiO 2 The ionic radius of Ti is similar to that of ZnO, Ti enters ZnO crystal grains in the form of trivalent or tetravalent Ti ions, and a substitution reaction is carried out to generate a substitution solid solution. Ti 4+ The high valence cations are ionized into monovalent or divalent effective donor centers at lattice sites, and the depletion layer donor concentration is increased continuously, so that the grain boundary barrier potential is reduced, and the nonlinear coefficient is reduced accordingly, which is one of the reasons for reducing the voltage gradient. With doped TiO 2 The leakage current increases rapidly with increasing content, since the decrease of the barrier potential of the grain boundary also has an effect on the leakage current, while Ti 4+ More free radicals and increased current density.
(2) XRD analysis
The XRD patterns of example 4, example 5, example 6, example 7 and example 8 are shown in fig. 1. The experimental result shows that the main crystal phase is ZnO phase, and a small amount of Bi exists 2 O 3 Phase, illustrating doping with different amounts of TiO 2 Has no significant influence on the main crystal phase of the sample. When doped with a small amount of TiO 2 Some small peaks of secondary phase, i.e. Bi, appear thereafter 4 Ti 3 O 12 Phase and Zn 2 TiO 4 A spinel phase. TiO 2 2 And Bi 2 O 3 Bi produced by the reaction 4 Ti 3 O 12 The liquid phase can promote grain growth. But TiO 2 2 Zn formed by reaction with ZnO 2 TiO 4 The spinel phase segregation improves the potential barrier of the crystal boundary at the crystal boundary, which is not beneficial to the growth of the crystal grains. No MnO was found 2 ，Co 3 O 4 ，Ni 2 O 3 Etc., which is likely to be due to the fact that these dopants, added in small amounts, dissolve in the grains or exist in the form of secondary phases at the grain boundaries.
(3) SEM analysis
SEM images of example 4, example 5, example 6, example 7 and example 8 are shown in FIGS. 2 to 6. The microstructure of all samples was relatively uniform and dense. Doped TiO 2 2 After that, the grain size increases due to TiO 2 And Bi 2 O 3 Bi produced by the reaction 4 Ti 3 O 12 The low co-dissolved liquid phase greatly accelerates the mass transfer process so as to promote the growth of crystal grains. In which the grains of example 6 were slightly reduced, probably due to the doped TiO 2 Zn formed by reaction with ZnO 2 TiO 4 The spinel phase inhibits grain growth. When TiO is present 2 And Bi 2 O 3 If the ratio of (B) is greater than 1.5, Bi is present 4 Ti 3 O 12 And Zn 2 TiO 4 The phases are collected in the grain boundary to hinder the grain growth. The pores appearing inside the crystal grains are due to Bi caused by sintering at a high temperature of 1250 ℃ 2 O 3 And (6) volatilizing.
(4) And (3) macroscopic performance detection: including density detection
FIG. 7 shows the calculation of TiO at 1250 ℃ sintering temperature using Archimedes' method for all examples 2 Relative compactness of the ZnO-doped pressure sensitive ceramic. The relative density of the green compact is about 60%, and after sintering, the relative densities are respectively 96.8%, 96.8%, 96.9%, 96.9%, 97.1%, 96.7%, 96.9% and 96.9%, and it can be seen that the densities of all samples are higher than 96%. With example 5 having the highest density. Overall, TiO doping 2 The doping has little influence on the compactness of the sample, and the obtained compactnessThe degrees are all higher.
(5) E-J Curve analysis
FIG. 8 shows E-J curves of examples 4, 5, 6, 7 and 8. The inflection point appearing between the pre-breakdown region and the breakdown region of the E-J curve is a non-ohmic characteristic. The larger the curve inclination, the larger the nonlinear coefficient, and the better the pressure-sensitive performance. It can be seen from the figure that with TiO 2 With the increase in the amount, all samples had non-linear characteristics, with the non-linear characteristic of example 5 being the best. This is because when TiO is used 2 When the doping amount of (3) is 0.5 mol%, the grain boundary barrier is high. The nonlinear coefficient is proportional to the schottky barrier. The nonlinear coefficient of the high grain boundary barrier is relatively high.
(6) Impedance spectroscopy
The ideal Nyquist impedance diagram (Cole-Cole diagram) and the classical equivalent circuit diagram of the ZnO voltage-sensitive ceramic are shown in FIG. 9. The equivalent circuit can explain not only the electrical characteristics of the sample, but also the properties of the ZnO voltage-sensitive ceramic. Wherein Z 'and Z' are respectively real and imaginary parts, R g Is the grain resistance, R gb Is grain boundary resistance, C gb For grain boundary capacitance, the two intersection intercepts at the high and low frequencies of the imaginary part are R g And R g +R gb . The principle can be explained by the following formulas (1) to (4). R g +R gb ≈R gb Since the grain boundary resistance is much larger than the grain boundary resistance, the sum of the grain boundary resistance and the grain boundary resistance can be regarded as the grain boundary resistance value. In order to explore TiO 2 Grain boundary response and conductivity of the ZnO low-pressure voltage-sensitive ceramic prepared by doping, and impedance spectra of samples of examples 4, 5, 6, 7 and 8 are tested at room temperature and are shown in FIG. 10. R g And R gb Are two parameters that may reflect the effect on the grain boundaries, texture and defects of the sample. It is difficult to obtain complete semicircular impedance at room temperature for the ZnO varistor, but from fig. 10(a), it is still possible to predict the trend of grain boundary resistance, which indicates that all samples have similar relaxation behavior. With TiO 2 The content is increased, the grain boundary resistance is gradually increased, and the electrical performance tends to be stable. For analyzing TiO in different component samples 2 Fig. 10(b) is a partial enlarged view at a high frequency, which is an effect on the grain resistance. Different TiO 2 The starting points of the samples at the contents are almost the same, indicating that TiO 2 The influence on the grain resistance is small.
z＝Z+jz" (1)
Figure BDA0003701076620000081
Figure BDA0003701076620000082
Figure BDA0003701076620000083
The foregoing is merely a preferred embodiment of the invention, which is intended to be illustrative and not limiting. It will be understood by those skilled in the art that various changes, modifications and equivalents may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (6)

1. The preparation method of the zinc oxide pressure-sensitive ceramic is characterized by comprising the following steps:
s1: ZnO and Bi are mixed 2 O 3 、Sb 2 O 3 、Ni 2 O 3 、Co 3 O 4 、MnO 2 、Al(NO 3 ) 3 、TiO 2 Mixing the powder in deionized water with ZrO 2 Ball-milling the medium at the speed of 200r/min for 12 hours, and drying at the temperature of 80 ℃ for 24 hours;
s2: mixing the dry powder obtained in step S1 with a binder, and then pressing into a green compact at 310 MPa;
s3: heating the green body obtained in the step S2 to 600 ℃ at the heating rate of 2 ℃/min for 2h, and removing the binder;
s4: and (4) sintering the green body without the binder obtained in the step S3 to 1200-1300 ℃ at the heating rate of 5 ℃/min, preserving the heat for 90min, and then cooling to room temperature to obtain the low-pressure-sensitive ceramic.
2. The method of claim 1, wherein the ZnO and Bi in step S1 2 O 3 、Sb 2 O 3 、Ni 2 O 3 、Co 3 O 4 、MnO 2 、Al(NO 3 ) 3 、TiO 2 The powder comprises 90-95 parts of ZnO by mole; bi 2 O 3 0.5-2 parts; sb 2 O 3 0.3-1 part; ni 2 O 3 0.2-1.5 parts; co 3 O 4 0.3-1.5 parts; MnO 2 0.3-1.5 parts; al (NO) 3 ) 3 0-0.5 parts; TiO 2 2 0 to 2 parts.
3. The method of claim 1, wherein the diameter of the green body in step S2 is 13 mm.
4. The method for preparing zinc oxide pressure-sensitive ceramic according to claim 1, wherein the temperature is reduced in step S4 to 900 ℃ at 1 ℃/min, then to 600 ℃ at 3 ℃/min, and finally to room temperature at 1 ℃/min.
5. A zinc oxide pressure sensitive ceramic prepared by the preparation method of any one of claims 1 to 4.
6. Use of the zinc oxide voltage sensitive ceramic of claim 5 for the protection of power electronic devices.
CN202210693087.XA 2022-06-17 2022-06-17 Zinc oxide pressure-sensitive ceramic, preparation method and application thereof Pending CN115124337A (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115959899A (en) * 2022-12-28 2023-04-14 安徽工程大学 Ga-doped zinc oxide composite functional ceramic, preparation method and application thereof
CN115974544A (en) * 2022-12-28 2023-04-18 安徽工程大学 In and Ta co-doped zinc oxide composite functional ceramic, preparation method and application thereof

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111548142A (en) * 2020-04-16 2020-08-18 华南理工大学 Heat preservation device for microwave sintering and method for microwave sintering of zinc oxide pressure-sensitive ceramic

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111548142A (en) * 2020-04-16 2020-08-18 华南理工大学 Heat preservation device for microwave sintering and method for microwave sintering of zinc oxide pressure-sensitive ceramic

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
《电工材料应用手册》编委会: "中国战略性新兴产业 新材料 功能陶瓷材料与器件", 中国铁道出版社, pages: 593 - 83 *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115959899A (en) * 2022-12-28 2023-04-14 安徽工程大学 Ga-doped zinc oxide composite functional ceramic, preparation method and application thereof
CN115974544A (en) * 2022-12-28 2023-04-18 安徽工程大学 In and Ta co-doped zinc oxide composite functional ceramic, preparation method and application thereof
CN115974544B (en) * 2022-12-28 2023-11-24 安徽工程大学 In and Ta co-doped zinc oxide composite functional ceramic, preparation method and application thereof

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