KR20200011632A - Zinc oxide based varistor composition, varistor using the same and method of manufacturing the varistor - Google Patents

Abstract

The present invention relates to a zinc oxide-based varistor composition comprising ZnO, ZnV_2O_6, and V_2O_5. Accordingly, the present invention has excellent electro-static discharge (ESD) resistance, a high non-linearity coefficient and a low leakage current, has excellent work stability when manufacturing, can be sintered at a low temperature of 1,000°C or less, and realizes an effect of reducing production costs.

Description

Zinc oxide varistor composition, varistor and varistor manufacturing method produced therefrom {ZINC OXIDE BASED VARISTOR COMPOSITION, VARISTOR USING THE SAME AND METHOD OF MANUFACTURING THE VARISTOR}

The present invention relates to a zinc oxide varistor composition comprising zinc oxide (ZnO) as a main component, a varistor prepared therefrom and a method for producing the varistor.

Varistors are nonlinear semiconductor resistors whose resistance values change with voltage. When the voltage increases excessively, the varistor protects the circuit or the device from overvoltage by energizing the increased current through the resistance change.

In general, varistors are prepared by sintering a composition containing a metal oxide as a main material. Conventionally, tin oxide (SnO ₂ ) -based materials, silicon carbide (SiC) -based materials, strontium titanide (SrTiO ₃ ) -based materials, and the like are used as main materials of varistor compositions, and recently, in order to further improve nonlinear characteristics, The use of interlocking materials is widely attempted.

Among these zinc oxide materials, bismuth-added zinc oxide (Bi-added ZnO) materials or praseodymium-added zinc oxide (Pr-added ZnO) materials are excellent in voltage nonlinearity, and have various surges and pulse noises. Excellent ability to protect electronic devices from the same abnormal voltage.

However, varistors containing bismuth-added ZnO materials can contain four types of polymorphs of bismuth oxide, resulting in lower breakdown voltages of approximately 10V or less, in which case ESD ( Electro-Static Discharge Resistance may be lowered.

In addition, varistors containing praseodymium-added zinc oxide (Pr-added ZnO) materials have the disadvantages of a large leakage current and somewhat low surge resistance, and a praseodymium oxide-based component (Pr ₆ O ₁₁ , Pr ₂ O _3, etc.). Since the high temperature of 1200 ℃ or more is required when sintering, and when applied to a stacked chip varistor, expensive precious metal components (Pd, Pt, etc.) are required as an internal electrode in a large manufacturing cost.

Therefore, while using zinc oxide (ZnO) as a main component, it is possible to eliminate the use of conventional bismuth oxide and praseodymium oxide, at the same time has a high nonlinear coefficient and low leakage current, excellent work stability during manufacturing, low temperature sintering is possible The need for varistor compositions that can reduce manufacturing costs is increasing.

One object of the present invention is to omit the use of bismuth oxide or praseodymium oxide, while having excellent ESD resistance, high nonlinear coefficient and low leakage current, excellent work stability during manufacturing, and sintering at low temperature below 1,000 ° C, The present invention relates to a zinc oxide varistor composition capable of reducing production costs, and a varistor and a varistor manufacturing method manufactured therefrom.

One embodiment of the present invention relates to a zinc oxide varistor composition comprising ZnO, ZnV ₂ O ₆ and V ₂ O ₅ .

In embodiments, the zinc oxide varistor composition may be one containing Bi ₂ O ₃ , Pr ₆ O ₁₁ or Pr ₂ O ₃ .

In embodiments, the zinc oxide varistor composition comprises: 97 mol% to 99.7 mol% ZnO; And ZnV ₂ O ₆ 0.1 mol% to 1.5 mol%; And V ₂ O ₅ 0.1 mol% to 1.5 mol%; It may include.

In embodiments, the molar ratio of ZnV ₂ O ₆ and V ₂ O ₅ may be 1: 0.8 to 1: 1.2.

In embodiments, the zinc oxide varistor composition may include manganese oxide as a first auxiliary oxide.

In embodiments, the zinc oxide varistor composition comprises: 97 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; And 0.1 mol% to 1 mol% Mn ₃ O ₄ ; It may include.

In embodiments, the zinc oxide varistor composition may include a second auxiliary oxide including at least one of cobalt oxide, nickel oxide, chromium oxide, calcium oxide, antimony oxide, and magnesium oxide.

In embodiments, the zinc oxide varistor composition may comprise 90 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; And 0.1 mol% to 9.8 mol% of the second auxiliary oxide; It may include.

In embodiments, the zinc oxide varistor composition may include both a first auxiliary oxide and a second auxiliary oxide.

In embodiments, the zinc oxide varistor composition may comprise 89.9 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; 0.1 mol% to 1 mol% of the first auxiliary oxide; And 0.1 mol% to 9.8 mol% of the second auxiliary oxide; It may include.

In embodiments, the zinc oxide varistor composition may be a eutectic liquid ZnV ₂ O ₆ and V ₂ O ₅ at 600 ° C to 800 ° C.

In an embodiment, the zinc oxide varistor composition may have a sinter densification temperature of 600 ° C to 800 ° C.

Another embodiment of the present invention relates to a varistor formed from the above-described zinc oxide varistor composition and comprising ZnO, ZnV ₂ O ₆ and V ₂ O ₅ .

In embodiments, the varistor may have a shape of one or more of disk, bulk, chip and stacked.

Yet another embodiment of the present invention relates to a varistor manufacturing method comprising sintering the above-described zinc oxide varistor composition at 700 ° C to 1,000 ° C.

The present invention omits the use of bismuth oxide or praseodymium oxide, has excellent ESD resistance, high nonlinearity coefficient and low leakage current, excellent work stability during manufacturing, sintering at low temperature below 1,000 ° C, A zinc oxide-based varistor composition which can be saved, and a varistor prepared therefrom and a method for producing the varistor are provided.

FIG. 1 illustrates current-voltage characteristics (IV curves) of ZnO-based varistors for low temperature sintering prepared in Examples 1 to 7 of the present invention.
2 is a view showing a disk-type varistor manufactured according to an embodiment of the present invention.
3 is a view showing a bulk varistor manufactured according to another embodiment of the present invention.
4 is a view showing a stacked varistor manufactured according to another embodiment of the present invention.

One embodiment of the present invention relates to a zinc oxide varistor composition comprising ZnO, ZnV ₂ O ₆ and V ₂ O ₅ .

Through this, the present invention has an excellent ESD resistance, high nonlinear coefficient and low leakage current, excellent work stability during manufacturing, sintering at a low temperature of less than 1,000 ℃, implements the effect of reducing the production cost.

In addition, the zinc oxide varistor composition does not include bismuth oxide or praseodymium oxide, that is, excludes bismuth oxide and praseodymium oxide. Through this, it is possible to solve the problem that the breakdown voltage is lowered by the bismuth oxide in the polymorphs state when the bismuth oxide is included in the prior art, and the electrostatic discharge (ESD) prevention property is lowered. When included, it is possible to solve the problem of increased leakage current and deterioration of various surge contents. In this case, it is possible to implement more advantageous characteristics to be applied as a varistor of an electronic circuit, an electric element or the like.

In an embodiment, the bismuth oxide may be Bi ₂ O ₃ , Bi ₂ O _5, or the like, and the praseodymium oxide may be Pr ₆ O ₁₁ , Pr ₂ O _3, or the like. For example, the zinc oxide based varistor composition Bi ₂ O ₃ ratio including type (Bi ₂ O ₃ free), Pr ₆ O ₁₁ non-embedded type (Pr ₆ O ₁₁ free) and / or Pr ₂ O ₃ ratio-contained (Pr ₂ O ₃ free) and the like. In such a case, the varistor composition can achieve higher nonlinearity and lower leakage current.

Zinc oxide (ZnO) in the zinc oxide varistor composition may be included in more than 89.9 mol%, 90 mol%, 97 mol% or more, for example, 89.9 mol% to 99.7 mol% or 97 mol% to 99.7 mol It may be included in an amount of%. Within this range, the zinc oxide varistor composition can realize higher nonlinearity and lower leakage current without including bismuth oxide or praseodymium oxide.

In the zinc oxide varistor composition, by adding ZnV ₂ O ₆ and V ₂ O ₅ to zinc oxide (ZnO), an eutectic liquid formed between the two materials functions as a liquid sintering aid. In this case, it is possible to prevent the problem of non-linearity deterioration and leakage current increase when V ₂ O ₅ is added to ZnO without adding ZnV ₂ O ₆ as in the related art, and at the same time, excellent ESD resistance can be realized.

The process liquid phases of the ZnV ₂ O ₆ and V ₂ O ₅ may be formed, for example, at 600 ° C. to 800 ° C., that is, the eutectic points of ZnV ₂ O ₆ and V ₂ O _{5 in} the zinc oxide varistor composition. point) may be 600 ° C to 800 ° C, for example 600 ° C. In this case, the nonlinear characteristics of the zinc oxide varistor composition may be further improved.

ZnV ₂ O ₆ in the zinc oxide varistor composition may be included, for example, in an amount of 0.1 mol% to 1.5 mol% or 0.1 mol% to 1 mol%. Within this range, the zinc oxide-based varistor composition can realize better ESD resistance while preventing problems of nonlinearity degradation and leakage current increase that may occur when V ₂ O ₅ is added.

V ₂ O ₅ in the zinc oxide varistor composition may be included, for example, in an amount of 0.1 mol% to 1.5 mol% or 0.1 mol% to 1 mol%. Within the above range, the zinc oxide varistor composition may realize more excellent ESD resistance, and may improve the low temperature sintering characteristics that can be sintered at a temperature of 1,000 ° C. or less of the zinc oxide varistor composition.

In embodiments, the molar ratio of ZnV ₂ O ₆ and V ₂ O ₅ may be 1: 0.8 to 1: 1.2, for example 1: 0.9 to 1: 1.1 or 1: 1. Within this range, the zinc oxide varistor composition has excellent work stability during manufacture, can be sintered at a low temperature of 1,000 ° C. or less, and can further improve the effect of reducing the production cost.

In one embodiment, when ZnV ₂ O ₆ and V ₂ O ₅ is added in a molar ratio of 1: 1 in the zinc oxide varistor composition of the present invention, ZnV ₂ O ₆ and V ₂ O ₅ is a process liquid phase is formed The eutectic point may be 600 ° C. In this case, the increase ZnV ₂ O _6, and V ₂ O ₅ of the process liquid without not only more beneficial to be used as a liquid phase sintering aid, ZnV the ₂ O _6, and V ₂ O ₅ the content of the process liquid to form a waste, While reducing the sintering temperature of the zinc oxide varistor composition, the degree of sinter densification can be increased, and the sinterability can be further improved.

The total of ZnV ₂ O ₆ and V ₂ O _{5 in} the zinc oxide varistor composition may be, for example, 0.2 mol% to 3 mol% and 0.2 mol% to 2 mol%. Within this range, the zinc oxide varistor composition can further improve nonlinearity, lower leakage current, and at the same time implement excellent ESD resistance and anti-surge characteristics, and can further improve overall physical properties required for the varistor. .

In one embodiment, the zinc oxide varistor composition comprises: 97 mol% to 99.7 mol% ZnO; And ZnV ₂ O ₆ 0.1 mol% to 1.5 mol%; And V ₂ O ₅ 0.1 mol% to 1.5 mol%; It may include. Within the above range, the zinc oxide varistor composition realizes high nonlinearity, low leakage current, and excellent ESD resistance, and has excellent work stability during manufacturing, and is capable of sintering at a low temperature of less than 1,000 ° C., which reduces production costs. The effect can be further improved.

The zinc oxide varistor composition may include manganese oxide as a first auxiliary oxide. The manganese oxide may include, for example, one or more of MnO, MnO ₂ , Mn ₂ O _3, and Mn ₃ O ₄ . In this case, the zinc oxide varistor composition can further improve physical properties such as low sintering temperature, high nonlinear coefficient, and low leakage current.

Manganese oxide in the zinc oxide varistor composition may be included, for example, 0.1 mol% to 1 mol%. In this case, the zinc oxide varistor composition may further improve the overall physical properties of the varistor, further promote the densification and grain growth of the zinc oxide, thereby increasing the sintering density and lowering the voltage of the varistor.

In one embodiment, the zinc oxide varistor composition comprises: 97 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; And 0.1 mol% to 1 mol% Mn ₃ O ₄ ; It may include. Within the above range, the zinc oxide varistor composition realizes high nonlinearity, low leakage current, and excellent ESD resistance, and has excellent work stability during manufacturing, and is capable of sintering at a low temperature of less than 1,000 ° C., which reduces production costs. The effect can be further improved.

The zinc oxide varistor composition may further include a second auxiliary oxide including at least one of cobalt oxide, nickel oxide, chromium oxide, calcium oxide, antimony oxide, and magnesium oxide. In this case, the total amount of the second auxiliary oxide in the zinc oxide varistor composition may be 0.1 mol% to 9.8 mol% in total. Within this range, while further promoting the densification and grain growth of zinc oxide, the sintered density can be further improved, and the overall physical properties of the varistor can be improved.

The cobalt oxide may further improve the nonlinearity of the zinc oxide varistor composition and lower the leakage current. For example, the cobalt oxide may be Co ₃ O ₄ . The content of cobalt oxide may be 0.1 mol% to 1 mol%. Within this range, it is possible to further improve the overall physical properties of the varistor.

The nickel oxide may further improve nonlinearity of the zinc oxide varistor composition, lower leakage current, and increase allowable voltage of the varistor. For example, the nickel oxide may be NiO. The nickel oxide content may be 0.1 mol% to 0.5 mol%. Within this range, it is possible to further improve the overall physical properties of the varistor.

The chromium oxide may further improve nonlinearity of the zinc oxide varistor composition and lower leakage current. For example, the chromium oxide may be Cr ₂ O ₃ . The content of the chromium oxide may be 0.1 mol% to 0.3 mol%. Within this range, it is possible to further improve the overall physical properties of the varistor.

The calcium oxide can further improve the nonlinearity of the zinc oxide varistor composition, further reduce the leakage current, increase the initial densification degree, form zinc oxide particles small and uniform during the sintering process, and increase the allowable voltage of the varistor. Can be. The calcium oxide may be calcium carbonate, for example CaCO ₃ . The calcium oxide content may be 0.2 mol% to 3 mol%. Within this range, it is possible to further improve the overall physical properties of the varistor.

The antimony oxide may further improve nonlinearity of the zinc oxide varistor composition, lower leakage current, increase sintering density, lower sintering temperature, form zinc oxide particles small and uniformly during sintering, and varistor physical properties. It is possible to increase the stability and to further increase the voltage control characteristics. For example, the antimony oxide may be Sb ₂ O ₃ . The content of the antimony oxide may be 0.1 mol% to 2 mol%. Within this range, it is possible to further improve the overall physical properties of the varistor.

The magnesium oxide may further improve nonlinearity of the zinc oxide varistor composition, lower leakage current, and increase sintered density. For example, the magnesium oxide may be MgO. The magnesium oxide content may be 0.2 mol% to 3 mol%. Within this range, it is possible to further improve the overall physical properties of the varistor.

In one embodiment, the zinc oxide varistor composition comprises 90 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; And 0.1 mol% to 9.8 mol% of the second auxiliary oxide; It may include.

In another embodiment, the zinc oxide varistor composition may include both a first auxiliary oxide and a second auxiliary oxide. For example, the zinc oxide varistor composition may comprise 89.9 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; 0.1 mol% to 1 mol% of the first auxiliary oxide; And 0.1 mol% to 9.8 mol% of the second auxiliary oxide; It may include.

In an embodiment, the zinc oxide varistor composition may have a sinter densification temperature of 600 ° C to 800 ° C. In this case, the zinc oxide varistor composition is capable of low temperature sintering at a temperature of less than 1,000 ℃, for example 600 ℃ to 1,000 ℃, 700 ℃ to 1,000 ℃, 700 ℃ to 900 ℃, or 700 ℃ to 800 ℃, The manufacturing cost can be further reduced.

In an embodiment, the zinc oxide varistor composition may be prepared by any known manufacturing method including an oxide mixing method. In addition, the composition powder thus prepared is generally dry molding, cold isostatic molding (CIP) or warm isostatic molding (HIP), extrusion molding, tape casting, such as any molding method known in the art arbitrarily Can be applied to form and sinter to the desired shape.

Another embodiment of the present invention relates to a varistor formed from the above-described zinc oxide varistor composition and comprising ZnO, ZnV ₂ O ₆ and V ₂ O ₅ .

In embodiments, the varistor may have a shape of one or more of disk, bulk, chip and stacked.

Another embodiment of the present invention relates to a varistor manufacturing method comprising sintering the above-described zinc oxide varistor composition at 600 ° C to 1,000 ° C, more specifically at 700 ° C to 1,000 ° C.

Such a method for producing a varistor can be carried out by employing a method known in the art, except for using the zinc oxide varistor composition of the present invention described above.

For example, after mixing each material of the varistor composition of the present invention described above by all known manufacturing methods including an oxide mixing method and the like, the composition powder thus prepared is generally made of all materials including a doctor blade and the like. The known thick film can be manufactured and sintered into a sheet or the like and coated with electrode materials on both sides thereof to produce various varistors.

2 is a view showing a disk varistor 10 manufactured according to an embodiment of the present invention, Figure 3 is a view showing a bulk varistor 20 manufactured according to another embodiment of the present invention.

2 and 3, the above-described zinc oxide-based varistor composition powder is molded and sintered into a single disk 12 or bulk 22, and then coated on both surfaces of the disk 12 or bulk 22. By applying a metal electrode material to form the metal electrode 13 or 23, respectively, a general disc type 10 or bulk type 20 varistor can be manufactured. The electrode material may be a known electrode material such as Ag, Pd, Ag / Pd alloy. In the disk type varistor 10, which cannot be surface mounted, lead wires 14 may be attached to the metal electrodes 13 for input and output of electrical signals.

4 is a diagram illustrating a stacked varistor 30 manufactured according to another embodiment of the present invention. Referring to FIG. 4, the above-described zinc oxide varistor composition powder is formed into a plurality of sheets, and then, a plurality of sheets are stacked to form a laminate 32, and a pile to be disposed on the uppermost layer and the lowermost layer, respectively. Except for the dummy sheet (that is, the sheet on which the electrode is not applied), the sheets to be stacked therein are coated with an electrode material for forming the internal electrode 33 on the surface thereof, and the sheets and dummy sheets therein. The laminated varistor 30 can be manufactured by laminating | stacking these in order and then sintering. Similarly, the electrode material may be a known electrode material such as Ag, Pd, Ag / Pd alloy. In addition, an external electrode terminal 35 may be formed at both ends of the varistor 30 for electrical signal input and output, and may be electrically connected to the internal electrodes 33, respectively.

In one embodiment, the sheet may be manufactured as a stacked chip varistor of a known structure in which a plurality of sheets are stacked and inner and outer electrodes are formed. In this case, the internal electrode and the external electrode can use a low-cost internal electrode such as 100% Ag or Al, Al-Ag instead of noble metal components such as Pd, Pt can significantly reduce the manufacturing cost.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the following examples are intended to illustrate the present invention more specifically, but the scope of the present invention is not limited by the following examples. The following examples can be appropriately modified and changed by those skilled in the art within the scope of the present invention.

Examples 1-7

The components in Table 1 were weighed at a predetermined composition ratio, and mixed with a distilled water three times the weight of the weighing material into a ball mill using a ball of 5 mm Φ partially stabilized zirconia (YSZ), mixed, and ground. Then, dewatering and drying were performed to prepare granulated powder, which was used as a starting material.

A predetermined amount of starting material powder was put into a 10 mm Φ molding mold and uniaxially molded at a pressure of 50 MPa to produce a disc type, which was 700 ° C. (Examples 1 to 2), 800 ° C. (Examples 3 to 4), and 900 ° C. (Examples 5-6) and it sintered in air at 1000 degreeC (Example 7) for 1 hour.

The sintered body thus obtained was polished on both sides to produce a thickness of about 1 mm, and then coated with an ohmic contact Ag paste to be used as an electrode on both ends of the ceramic sintered body, followed by baking for 10 minutes at 550 ° C. to form an external electrode. A test piece for measuring the physical properties was produced.

(Unit: weight%) ZnO ZnV ₂ O ₆ V ₂ O ₅ Mn ₃ O ₄ CaCO ₃ Sb ₂ O ₃ Example 1 99.0 0.5 0.5 - - - Example 2 98.7 0.5 0.5 0.3 - - Example 3 98.7 0.5 0.5 0.3 - - Example 4 98.2 0.5 0.5 0.3 0.5 - Example 5 98.7 0.5 0.5 0.3 - - Example 6 98.7 0.5 0.5 0.3 0.5 - Example 7 98.7 0.5 0.5 0.3 - 0.5

Test Example: Measurement of Physical Properties of Varistor Devices

The current-voltage (IV) characteristics of the varistor specimens manufactured in Examples 1 to 7 were measured by applying a log stair pulse waveform at room temperature using a DC current voltage power supply and measurement instrument (Kiesley 237). It was. The results are shown in FIG.

The varistor voltage (V _n ), which is a current-voltage characteristic parameter, was measured in [V / mm] as the voltage when 1 mA / cm 2 current flowed, and the leakage current (I _L ) was measured at 80% of V _n . [㎂ / cm ² ], and the nonlinear coefficient (α) was obtained using the following formula (1). The measured values are shown in Table 2 below.

[Equation 1]

In Equation 1, E ₁ and E ₂ are electric fields at J ₁ (= 1 mA / cm ² ) and J ₂ (= 10 mA / cm ² ), respectively.

Sintering Temperature
(℃) Relative density
(g / cm ³ ) Vn
(V / mm) Nonlinear coefficient
(α) Leakage current
(㎂ / cm ² ) Example 1 700 97.2 2,590 45 292 Example 2 700 96.7 3,312 45 20 Example 3 800 97.4 2,225 50 16 Example 4 800 97.0 3,226 57 61 Example 5 900 97.6 524 60 43 Example 6 900 97.2 537 49 45 Example 7 1000 97.1 419 49 29

As confirmed through Table 2 and FIG. 1, the varistor made of the varistor composition of the present invention has high density, excellent nonlinearity in the composition range, and low leakage current.

The composition has a high nonlinear coefficient and a low leakage current, and in particular, proposes a new liquid sintering preparation compound that compensates for the shortcomings of V ₂ O ₅ and Bi ₂ O ₃ , which are liquid sintering aids previously used at more than 900 ℃. .

On the other hand, when only V ₂ O ₅ is added, the sintering is easy at 900 ° C., but the leakage current is high and the nonlinearity is low. When Bi ₂ O ₃ is added, the ESD resistance is poor. In addition, in the case of including the Pr-based oxide component, high temperature sintering is required, resulting in an increase in manufacturing cost.

(Research related to this application (No. 20171210000180) is a research project carried out with the support of the Ministry of Trade, Industry and Energy (MOTIE) and the Korea Institute of Energy Research and Evaluation (KETEP).)

ACKNOWLEDGMENTS

This work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea (No. 20171210000180).

10: disc type varistor
20: bulk varistor
30: stacked varistors
12: disk
22: bulk
23: laminate
13, 23: metal electrode
14: lead wire
33: internal electrode
35: external electrode terminal

Claims (15)

A zinc oxide varistor composition comprising ZnO, ZnV ₂ O ₆ and V ₂ O ₅ .
The method of claim 1,
The zinc oxide varistor composition is a zinc oxide varistor composition, characterized in that it does not contain Bi ₂ O ₃ , Pr ₆ O ₁₁ or Pr ₂ O ₃ .
The method of claim 1,
The zinc oxide varistor composition comprises: ZnO 97 mol% to 99.7 mol%; And ZnV ₂ O ₆ 0.1 mol% to 1.5 mol%; And V ₂ O ₅ 0.1 mol% to 1.5 mol%; Zinc oxide varistor composition comprising a.
The method of claim 1,
The molar ratio of ZnV ₂ O ₆ and V ₂ O ₅ is 1: 0.8 to 1: 1.2 zinc oxide varistor composition, characterized in that.
The method of claim 1,
The zinc oxide varistor composition is a zinc oxide varistor composition comprising a manganese oxide as a first auxiliary oxide.
The method of claim 5,
The zinc oxide varistor composition comprises: ZnO 97 mol% to 99.7 mol%; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; And 0.1 mol% to 1 mol% Mn ₃ O ₄ ; Zinc oxide varistor composition comprising a.
The method of claim 1,
The zinc oxide varistor composition is a zinc oxide varistor composition comprising a second auxiliary oxide containing at least one of cobalt oxide, nickel oxide, chromium oxide, calcium oxide, antimony oxide and magnesium oxide.
The method of claim 7, wherein
The zinc oxide varistor composition is 90 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; And 0.1 mol% to 9.8 mol% of the second auxiliary oxide; Zinc oxide varistor composition comprising a.
The method of claim 1,
The zinc oxide varistor composition further includes a first auxiliary oxide and a second auxiliary oxide,
The first auxiliary oxide may be manganese oxide; The second auxiliary oxide is at least one of cobalt oxide, nickel oxide, chromium oxide, calcium oxide, antimony oxide and magnesium oxide; zinc oxide varistor composition, characterized in that.
The method of claim 9,
The zinc oxide varistor composition may comprise 89.9 mol% to 99.7 mol% ZnO; A total of 0.2 mol% to 2 mol% of ZnV ₂ O ₆ and V ₂ O ₅ ; 0.1 mol% to 1 mol% of the first auxiliary oxide; And 0.1 mol% to 9.8 mol% of the second auxiliary oxide; Zinc oxide varistor composition comprising a.
The method of claim 1,
The zinc oxide varistor composition is a zinc oxide varistor composition, characterized in that ZnV ₂ O ₆ and V ₂ O ₅ form a eutectic liquid state at 600 ℃ to 800 ℃.
The method of claim 1,
The zinc oxide varistor composition has a sintered densification temperature of 600 ℃ to 800 ℃ zinc oxide varistor composition.
A varistor formed from the zinc oxide varistor composition according to claim ₁ and comprising ZnO, ZnV ₂ O ₆ and V ₂ O ₅ .
The method of claim 13,
The varistor is a varistor having a shape of at least one of the disk type, bulk type, chip type and stacked type.
A varistor manufacturing method comprising sintering a zinc oxide varistor composition according to claim 1 at 700 ° C to 1,000 ° C.

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