JPH10270214A - Laminated junction body of nonlinear resistor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laminated junction body of nonlinear resistors having a high junction strength and a superior withstand voltage characteristic. SOLUTION: A laminated junction body is formed by junction elements 1, containing a zinc oxide as main components to each other by applying a cementing material containing 80-98 wt.% conductive metal, such as silver, gold, etc., and glass, such as the silicate glass, etc., to the upper and lower surfaces of an elements 1 and heat-treating a material 3 within the temperature range of 200-600 deg.C. Then insulating layers 2 are formed on the entire side faces of the function body by applying an insulating material to the side faces and baking the insulating material. At the time of forming the laminated body, the electrode diameter ratio, namely, a ratio R2/R1 to the diameter R2 or the cementing material 3 to that R1 of the element 1 is adjusted to be in the range of 0.9<R2/R1<=1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-linear resistor used for lightning arresters, surge absorbers and the like, that is, a non-linear resistor laminated by stacking elements made of a sintered body mainly composed of zinc oxide. It relates to a joined body.

[0002]

2. Description of the Related Art Generally, in an electric power system, an overvoltage protection device such as a lightning arrester or a surge absorber is used to remove an overvoltage superimposed on a normal voltage and protect the electric power system and electric equipment. The overvoltage protection device is often made of a non-linear resistor having a characteristic of substantially exhibiting an insulating property at a normal voltage and having a low resistance value when an overvoltage is applied.

In general, an element containing zinc oxide as a main component is used as a nonlinear resistor. This element is obtained by adding at least one kind of metal oxide such as bismuth oxide, antimony oxide, manganese dioxide, nickel oxide, etc. to zinc oxide as an additive to obtain nonlinear characteristics, mixing,
It is a sintered body that has been granulated, molded and sintered. In general, an insulating layer is formed on the side surface of each element, and electrodes such as aluminum are formed on both end surfaces by arc spraying or the like, thereby forming a non-linear resistor.

A nonlinear resistor having such a configuration is:
Since it is difficult to manufacture a large-sized one, a required number of such layers are laminated according to the system voltage, and the laminated state is used for an arrester, a surge absorber and the like. However, when a large number of non-linear resistors are stacked, it is necessary to use a support rod made of an insulator to fix them, so that there is a problem that the diameter of the porcelain tube becomes large and the cost increases.

Therefore, integration of the non-linear resistor is required, and a conductive bonding technique has been developed. For example, Japanese Patent Application Laid-Open No. 7-212520 discloses a technique for joining electrodes using a metal ring and an epoxy-based conductive adhesive. That is, according to this technique, electrodes such as aluminum are provided on both end surfaces of the element, and as a bonding material between the elements and between the element and the terminal metal, an epoxy-based conductive adhesive and a metal for preventing the adhesive from protruding. The element and the terminal metal are integrated by using a ring.

[0006]

However, in the laminated joined body using the conductive joining technique disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 7-21520, the joining strength between the element and the electrode is low, and There is a problem that reliability is low due to the complicated structure of the joining portion.

An object of the present invention is to solve the above-mentioned conventional problems and to provide a laminated joined body of non-linear resistors having high joining strength and excellent withstand voltage characteristics.

[0008]

According to a first aspect of the present invention, there is provided a laminated joined body of non-linear resistors according to the first aspect of the present invention. In the joined body, the element and the element are joined with one layer of a conductive joining material, and a heat treatment temperature at the time of joining with the conductive joining material is in a range of 200 ° C to 600 ° C.

According to the first aspect of the present invention, the bonding strength can be increased by forming a single-layer structure using a conductive bonding material without forming a sprayed electrode between the elements.
By setting the joining temperature in the range of 200 ° C. to 600 ° C., the joining strength can be increased and the resistance ratio can be set to a good value. For this reason, the joining strength is high, and
A laminated joined body of non-linear resistors having excellent withstand voltage characteristics can be obtained.

According to a second aspect of the present invention, there is provided a laminated joined body of non-linear resistors according to the first aspect of the present invention, wherein the entire side surface comprising the element and the conductive joining material is coated with an insulating layer. Features.

According to the second aspect of the present invention, since the insulating layer is formed not only on the element but also on the side surface of the conductive bonding material, the withstand voltage characteristics can be improved.

According to a third aspect of the present invention, there is provided a laminated joined body of non-linear resistors according to the first or second aspect.
The conductive bonding material is composed of a conductive metal material selected from conductive metal materials including gold and silver, and a glass material, and the content of the conductive metal material is 80 wt% to 98 wt%.
It is characterized by being within the range of wt%.

According to the third aspect of the present invention, since the content of the conductive metal material is an optimum value, the resistance ratio increases because the insulating component is too large, and the bonding strength because the glass component is too small. , And a laminated joined body having excellent characteristics can be obtained.

According to a fourth aspect of the present invention, there is provided the laminated junction of the non-linear resistor according to any one of the first to third aspects, wherein the diameter of the element is R1, and the diameter of the conductive bonding material is R1. When R2, these ratios R2 / R1
Is in the range of 0.9 <R2 / R1 ≦ 1.

According to the fourth aspect of the present invention, since the bonding area and the current-carrying area are small, the bonding strength is reduced, and the resistance ratio is increased. By becoming the starting point of the entanglement, a withstand voltage characteristic does not decrease and a laminated joined body having excellent characteristics can be obtained.

According to a fifth aspect of the present invention, there is provided the laminated junction of the nonlinear resistor according to any one of the first to fourth aspects, wherein the terminal metal is made of a conductive bonding material in the element located at the end. It is characterized by being joined.

According to the fifth aspect of the present invention, the terminal metal is joined to the end of the laminated joined body by a conductive joining material and integrated, thereby reducing the size of the lightning arrester employing the non-linear resistor. And a highly reliable non-linear resistor can be obtained.

According to a sixth aspect of the present invention, there is provided the laminated junction body of the non-linear resistor according to the fifth aspect of the invention, wherein the conductive bonding material for bonding the element and the terminal metal includes the element and the terminal metal. The heat treatment temperature at the time of joining is 200 ° C.-6
It is characterized by being within the range of 00 ° C.

According to a seventh aspect of the present invention, there is provided the laminated joined body of non-linear resistors according to the fifth aspect of the present invention.
The material of the terminal metal is a material selected from aluminum or brass.

According to an eighth aspect of the present invention, in the laminated junction of the nonlinear resistor according to any one of the fifth to seventh aspects, the conductive bonding material for bonding the element and the terminal metal is used. , And solder.

According to the inventions described in claims 6 to 8, the bonding strength between the element and the terminal metal can be increased. Therefore, a laminated joined body having excellent characteristics can be obtained.

[0022]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a non-linear resistor according to an embodiment of the present invention; [1. First Embodiment] [1-1. Configuration] As a first embodiment of the present invention, an embodiment to which the inventions of claims 1 to 4 are applied is shown in FIG.
This will be described with reference to FIG.

First, manganese dioxide (MnO ₂ ), silicon dioxide (SiO ₂ ), and chromium oxide (Cr ₂ O ₃ ) are added to zinc oxide (ZnO) in an amount of 0.5 mol%, and bismuth oxide (Bi ₂ O _3), antimony oxide (Sb ₂ O _3), and as a raw material nickel oxide a (NiO) was added 1 mol%, respectively. Next, this raw material was put into a mixing device together with water and organic binders of a dispersant and mixed, and the mixture was spray-granulated by a spray drier or the like. And put these granulated powders in a mold and pressurize,
After being formed into a disk having a diameter of 40 mm and a thickness of 30 mm, the formed body was fired at 1200 ° C.

Next, as shown in FIG. 1, after the upper and lower surfaces of the sintered element 1 are polished, a conductive metal material, for example, a conductive metal such as silver (Ag) or gold (Au) is applied to the polished surface. When,
For example, a conductive bonding material 2 made of glass such as silicate (SiO ₂ ) glass was applied, and the element 1 was bonded by performing heat treatment while applying pressure. Then, an insulating material was applied to the entire side surface and baked at a predetermined temperature to form an insulating layer 3, thereby producing a laminated joined body of non-linear resistors.

Further, as shown in FIG. 2, before the bonding material 2 is applied, a sprayed electrode 4 made of, for example, aluminum is formed on the polished surface of the element 1 to produce a laminated bonded body of non-linear resistors. .

Further, as shown in FIG. 3, before joining the devices 1, an insulating material was applied to the side surfaces of each device 1 and baked at a predetermined temperature to form an insulating layer 3. Thereafter, a bonding material 2 was applied between the elements 1 and baked while applying pressure to produce a laminated bonded body of non-linear resistors.

In this case, in the present embodiment, the manufacturing conditions of the laminated joined body such as the amount of metal of the joining material 2, the baking temperature at the time of joining, the electrode diameter ratio, etc. in the above-described steps of producing the nonlinear resistor. By changing, a plurality of types of non-linear resistors were produced. Note that the electrode diameter ratio is represented by the diameter R2 of the bonding material 2 / the diameter R1 of the element 1 shown in FIG. Also, here
The metal amount of the joining material 2 was changed in the range of 95 to 99 wt%, and the baking temperature at the time of joining was changed in the range of 100 to 700 ° C.

[1-2. Characteristics Test of Laminated Joint] A test for determining the characteristics of the laminated joined body, that is, the bonding strength, the resistance ratio, and the withstand voltage, was performed on the plurality of types of nonlinear resistors manufactured as described above.

For each of the laminated joined bodies of non-linear resistors manufactured under the respective manufacturing conditions, ten samples of each kind are prepared. Here, the bonding strength is an average value of the shear bonding strength when a shear load is applied to the bonded body, and the resistance ratio is a current of 1 mA applied to the bonded body with respect to a resistivity when a current of 1 mA flows through the element 1 alone. Is the average value of the ratio of the resistivity when flowing. The withstand voltage is 4 × 10 μs
Of about 5 kV / cm to about 1 kV / cm
This test is an average of the maximum values of the electric field intensities that were not flashed as a result of conducting a test in which the application and the cooling were repeated by increasing and applying the voltage and then cooling.

Table 1 shows each of the laminated joints (joint Nos. 1 to 4).
No. 16) shows the manufacturing conditions, the bonding strength, the resistance ratio, and the results of the withstand voltage test. That is, the joined body No. 1, No. 3-No. 7, and No. 7 9-No.
Reference numeral 13 denotes a joined body in which the sprayed electrode is not formed and the insulating layer 3 is entirely formed as shown in FIG. 3-No. 7 have different bonding temperatures, and the bonded body No. 7 has a different bonding temperature. 9-No. 13 have different metal contents. In addition, the joined body No. 14-No. Similarly, 16 is a joined body in which the sprayed electrode is not formed and the insulating layer 3 is formed entirely, but the electrode diameter ratio (R2 / R
1) is different from the other bonded bodies, in which the case where the diameter R1 of the bonding material 2 is smaller than the diameter R1 of the element 1 and the case where the diameter R1 is larger are set.

[0031]

[Table 1] Furthermore, the joined body No. 2 is a joined body on which the sprayed electrode 4 is formed as shown in FIG. 8 is
As shown in FIG. 3, this is a joined body in which the thermal spray electrode 4 is not formed and the insulating layer 3 is formed for each element 1.

From the test results in Table 1, the following became clear. (1) Joint No. 1 and No. 1 From the result of No. 2, it was found that the joint having the sprayed electrode had a lower bonding strength than the joint having no sprayed electrode. That is, since the bonding strength between the thermal spray electrode 4 and the element 1 is low, if the thermal spray electrode 4 is formed and then bonded, the bonding strength of the laminated bonded body is reduced. Therefore, by forming a single-layer joining structure using the joining material 2 without forming a thermal spray electrode, a laminated joint having high joining strength can be obtained.

(2) Joint No. 1 and No. 1 3 to N
o. 7, it was found that the higher the bonding temperature of the bonding material 2, the higher the bonding strength. From these results, it was found that by setting the bonding temperature to 200 ° C. or higher, excellent bonding strength and excellent resistance ratio were obtained. Although not shown in Table 1, the element 1 has a property that the VI non-linearity is reduced by heat treatment at 650 ° C. or more. Therefore, the joining temperature of the joining material 2 is set to 200 ° C. to 6 ° C.
By setting the temperature to 00 ° C., a laminated joined body having excellent characteristics can be obtained.

(3) Joint No. 1 and No. 1 From the result of No. 8, it was found that the withstand voltage characteristics were higher when the insulating layer 3 was formed on the entire joined body than when the insulating layer 3 was formed only on the element 1 alone. This is because the bonding material 2 becomes a starting point of a flashover in a withstand voltage test, and thus the withstand voltage characteristics are higher when covered with the insulating layer 3.

(4) Joint No. 1 and No. 1 9-N
o. According to the result of No. 13, when the metal amount is 70 wt%, the insulating ratio in the bonding material 2 is too large, and the resistance ratio is increased. When the metal amount is 99 wt%, the bonding strength is lowered because the glass component is too small. I found out. Therefore,
By setting the amount of metal in the bonding material 2 to 80 wt% to 98 wt% and the glass component to 20 wt% to 2 wt%, a laminated bonded body having excellent characteristics can be obtained.

(5) Joint No. 1 and No. 1 14-N
o. From the result of No. 16, the electrode diameter ratio (R2 / R1) was 0.8.
In the case of, the bonding strength and the resistance ratio are increased because the bonding area and the conducting area are small. When the electrode diameter ratio is 1.01, the bonding material 2 protrudes from the element 1. It was found that the portion was likely to be the starting point of flashover, and the withstand voltage characteristics were low. Therefore, when the electrode diameter ratio is 0.9 <R2
By setting the ratio to / R1 ≦ 1, a laminated joined body having excellent characteristics can be obtained.

[1-3. Operation / Effect] As described above, according to the present embodiment, a single-layer joining structure is formed by the joining material 2 without forming the sprayed electrode, and the joining temperature of the joining material 2 is set to 200 ° C.
600 ° C., the whole of the laminated joined body is covered with the insulating layer 3, and the metal amount of the joining material 2 is set to 80 wt% to 98 wt%,
In addition, by setting the electrode diameter ratio in the range of 0.9 <R2 / R1 ≦ 1, a laminated joined body having excellent characteristics can be provided.

[2. Second Embodiment] As a second embodiment according to the present invention, an embodiment to which the inventions of claims 5 to 8 are applied will be described with reference to FIG. In the laminated joined body of the non-linear resistors, the terminal metal is formed at the end, so that the lightning arrester or the like can be further reduced in size.
The terminal metal 6 is provided in the laminated joined body shown in FIG.

First, a laminated joined body as shown in FIG. 1 was prepared by the same method as in the first embodiment, and a terminal metal 6 was joined thereto. Here, as in the first embodiment, the element 1 is connected to the element 1 as in the first embodiment.
And the terminal metal 6 were joined by the joining material 5. Thus, a laminated joined body with the terminal metal 6 shown in FIG. 4 was produced.

In the second embodiment, the manufacturing conditions such as the bonding temperature of the bonding material 5, the material of the terminal metal 6, and the material of the bonding material 5 are changed in the above-described manufacturing process of the non-linear resistor. Then, a test for determining the bonding strength of the bonding portion between the element 1 and the terminal metal 6 was performed. Table 2 shows the production conditions and the results of the joint strength tests for each of the laminated joints (joint Nos. 17 to 25). That is, the joined body N
o. 17-No. Reference numerals 22 all denote aluminum as the material of the terminal metal 6 and solder as the material of the joining material 5, and the joining temperature differs between 100 ° C and 600 ° C. In addition, the joined body No. 23 and No. 23. 24 is
The joining temperature is also 500 ° C. and the material of the joining material 5 is solder, but the terminal metal 6 is made of brass or SUS403.
It is. Furthermore, the joined body No. Reference numeral 25 indicates that the material of the terminal metal 6 is aluminum and the material of the bonding material 5 is a metallic glass material.

[0041]

[Table 2] From the test results in Table 2, the following became clear. That is, the joined body No. From the result of No. 17, it was found that the bonding strength was high when the bonding temperature of the bonding material 5 was 200 ° C or more. Further, for the same reason as in the first embodiment, by setting the joining temperature of the joining material 5 to 200 ° C. to 600 ° C., a laminated joined body having excellent characteristics can be obtained.

Further, the conjugate No. From the result of No. 24, it was found that the bonding strength was higher when the material of the terminal metal 6 was aluminum or brass than when the material was SUS403. In addition, the joined body No. From the result of No. 25, it was found that the bonding strength was higher when the material of the bonding material 5 was soldered than when the material was metal glass material.

Although not shown in Table 2, even when the bonding material 5 of the element 1 and the terminal metal 6 has not only solder but also a multilayer structure including solder, a laminated bonded body having excellent characteristics can be obtained. Has been confirmed.

As described above, according to the present embodiment, the joining temperature of the joining material 5 for joining the element 1 and the terminal metal 6 is set to 200 ° C.
-600 ° C., the material of the terminal metal 6 is aluminum or brass, and the material of the bonding material 5 is a solder or a multilayer structure including solder, whereby a laminated bonded body having excellent characteristics can be provided. .

[0045]

As described above, according to the present invention, the elements of the laminated joined body of non-linear resistors are joined with one layer of a conductive joining material, and the heat treatment temperature in the joining is set to 200 ° C. to 6 ° C.
The temperature is within the range of 00 ° C., and the entire side surface of the laminated joined body is coated with an insulating layer.
0 wt% to 98 wt%, and the electrode diameter ratio is 0.9.
By setting the range of <R2 / R1 ≦ 1, it is possible to provide a laminated joined body of non-linear resistors having high joining strength and excellent withstand voltage characteristics.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing an example of a laminated joined body of non-linear resistors according to the present invention.

FIG. 2 is a cross-sectional view showing an example of a laminated joined body of non-linear resistors according to the present invention.

FIG. 3 is a cross-sectional view showing an example of a laminated joined body of non-linear resistors according to the present invention.

FIG. 4 is a cross-sectional view showing an example of a laminated joined body of non-linear resistors according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Element 2 ... Bonding material 3 ... Insulating layer 4 ... Sprayed electrode 5 ... Bonding material 6 ... Terminal metal

Claims (8)

[Claims] 1. A laminated joined body of non-linear resistors formed by laminating elements made of a sintered body containing zinc oxide as a main component, wherein the elements are joined with one layer of a conductive joining material, A laminated joined body of non-linear resistors, wherein a heat treatment temperature at the time of joining with the conductive joining material is in a range of 200 ° C to 600 ° C. 2. The laminated joined body of non-linear resistors according to claim 1, wherein the entire side surface made of the element and the conductive joining material is coated with an insulating layer. 3. The conductive bonding material is composed of a conductive metal material selected from conductive metal materials including gold and silver, and a glass material, and the content of the conductive metal material is 8%.
3. The multilayered joined body of non-linear resistors according to claim 1, wherein the content is in a range of 0 wt% to 98 wt%. 4. When the diameter of the element is R1 and the diameter of the conductive bonding material is R2, the ratio R2 / R
4. The laminated joined body of non-linear resistors according to claim 1, wherein 1 is in a range of 0.9 <R2 / R1 ≦ 1. 5. 5. The multilayered joined body of non-linear resistors according to claim 1, wherein a terminal metal is joined to the element located at the end with a conductive joining material. 6. The heat treatment temperature of the conductive bonding material for bonding the element and the terminal metal at the time of bonding the element and the terminal metal is in a range of 200 ° C. to 600 ° C. Item 6. A laminated joined body of the nonlinear resistor according to Item 5. 7. The laminated joint according to claim 5, wherein the material of the terminal metal is a material selected from aluminum and brass. 8. The non-linear resistor laminate assembly according to claim 5, wherein the conductive bonding material for bonding the element and the terminal metal includes solder.