JP3442644B2 - Contact material for vacuum valve - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact material for a vacuum valve used for an electrode contact such as a vacuum circuit breaker which opens and closes a high voltage or a large current.

[0002]

2. Description of the Related Art Conventionally, the contacts in a vacuum valve of a vacuum circuit breaker have three basic requirements represented by welding resistance, withstand voltage, and breaking characteristics, as well as cutting characteristics, wear resistance, and wear resistance. It is composed of various material elements in order to maintain and improve contact resistance characteristics, temperature rise characteristics, and the like.

However, since the above-mentioned three basic requirements generally require material properties that are in conflict with each other, it is impossible to satisfy one element sufficiently. Therefore, by combining materials, bonding materials, etc., contact materials for vacuum valves (hereinafter simply referred to as contact materials) suitable for specific applications such as high current breaking applications, high withstand voltage applications, low cutting applications, etc. Is also being developed, and the current state is that it exhibits excellent characteristics.

As a contact material for breaking a large current for satisfying the three basic requirements of a general-purpose vacuum circuit breaker, for example, Cu-Bi containing 5% by weight or less of a fusion preventing component such as Bi or Te.
Alloys and Cu-Te alloys are known (Japanese Patent Publication No. 41-1).
No. 2131, Japanese Patent Publication No. 44-23751). Cu-Bi
In the alloy, the brittle Bi precipitated in the grain boundaries, and the Cu-Te alloy, the brittle Cu ₂ Te precipitated in the grain boundaries and in the grains embrittles the alloy itself and realizes a low welding detachment force, so that a large current interruption is achieved. It also has excellent characteristics. Among the alloys, the contact having Bi of, for example, about 10% by weight has an appropriate vapor pressure characteristic and therefore exhibits excellent current cutting characteristics (Japanese Patent Publication No. 35-14974).

However, Cu-Bi alloy, Cu-Te
The alloy is excellent in welding resistance and large current interruption characteristics, but is not satisfactory in withstand voltage characteristics.

A Cu-Cr alloy is known as a contact material for high withstand voltage and large current interruption which also satisfies the three basic requirements. Since this alloy has a smaller vapor pressure difference between constituent components than the Cu-Bi alloy and Cu-Te alloy, it has an advantage that uniform performance can be expected, and is excellent depending on the usage. However, although the Cu-Cr alloy is excellent in high withstand voltage and large current interruption characteristics, it is not satisfactory in welding resistance.

On the other hand, in recent years, it has become necessary to further improve the following cutting characteristics and breaking characteristics as a vacuum circuit breaker aiming at high reliability and miniaturization.

First, the current is cut off (or the current is switched) in a high vacuum by utilizing the diffusivity of an arc in a vacuum.
The contact of the vacuum valve that performs
It consists of two contacts. When a vacuum valve is used in an inductive circuit such as an electric motor load to cut off current without sufficient consideration, a transient abnormal surge voltage may be generated, which may affect the insulation of the load equipment.

The cause of this abnormal surge voltage is that when a small current is cut off in a vacuum, a cutting phenomenon occurs on the low current side (the current is forcibly forced without waiting for the natural zero point of the AC current waveform). This is due to the interruption, the high frequency arc extinguishing phenomenon, etc. The value Vs of the abnormal surge voltage is proportional to the surge impedance Zo of the circuit and the current cutting value Ic, so that the value Vs of the abnormal surge voltage is suppressed low. It is necessary to lower the current cutoff value Ic as one means for achieving the above requirement, and the Ag-WC alloy is used as one of the contact alloys useful for this requirement.

As the contact material for low cutting property, an Ag-WC alloy (Ag is 40%) which exhibits excellent low cutting property by the synergistic action of the thermoelectron emission effect of WC and the appropriate vapor pressure of Ag is used. Known (Japanese Patent Application No. 42-68447)
issue). Further, it has been suggested that the use of a contact material in which the particle diameter of the arc-resistant component material (for example, the particle diameter of WC) is 0.2 to 1 μm is effective in improving the cutting current characteristics (Japanese Patent Publication No. 61338). Further, by adopting a contact material having a WC-Co interparticle distance of 0.3 to 3 μm, the mobility of the arc cathode spot is improved, and a contact material having an improved large current interruption characteristic is also known. (JP-A-4-
206121). However, although these Ag-WC alloys have excellent cutting characteristics, they are not satisfactory in terms of large current breaking characteristics and compatibility between cutting characteristics and large current breaking characteristics.

Secondly, after the current is cut off in the vacuum circuit breaker, a flashover occurs in the vacuum valve, and a phenomenon in which the contacts become conductive again (the discharge does not continue thereafter) may be induced. This phenomenon is called re-ignition, and the mechanism of its occurrence has not been clarified, but an abnormal overvoltage is likely to occur because the electric circuit suddenly changes to the conductive state after the current is cut off. In addition, the occurrence of re-ignition significantly deteriorates the current interruption characteristic. Furthermore, the surface of the contact that has been subjected to a large current interruption is significantly damaged such as generation of cracks, selective evaporation, and falling off, resulting in material wear. When the contact is opened or closed next time, many secondary disadvantages are caused. Therefore, it is required to realize a stable contact with little wear even when a large current is cut off, together with the improvement of the breaking characteristics.

[0012]

As the low cutting type contact material for the vacuum valve as described above, the above-mentioned Cu-B is used.
i prior to the i alloy, Cu-Te alloy, and Cu-Cr alloy
Although the g-WC alloy has been applied, it is not a sufficient contact material for the requirement to further improve the low cutting property and the current cutoff property, but it is the actual situation, and both properties are more highly compatible. Is an important issue. Further Ag
-WC alloys contain a large amount of effective Ag, and therefore reduction of material cost is also an important issue.

For example, when the vacuum circuit breaker is applied to a capacitor circuit, the contact surface is remarkably damaged by an arc during current interruption and current opening / closing due to the fact that a voltage that is twice or three times the normal voltage is applied. As a result, the contact surface is roughened and the contacts are also worn out. Low cutting property Ag-W
The same phenomenon is observed in the C alloy, and there is an urgent need to develop and improve a contact material that has both a lower cutting property and a higher barrier property. That is, A which is preferable as the current interruption characteristic
According to an experiment in which even a circuit breaker equipped with a g-WC alloy causes a capacitor bank to be interrupted to cause re-ignition,
Generation of extremely large overvoltage and generation of excessive high-frequency current are observed, and the current cutoff characteristic is extremely deteriorated. As a result, the re-ignition occurrence is suppressed for the Ag-WC alloy,
There is a demand for the development of technology that improves the breaking characteristics.

Although the mechanism of occurrence of the re-ignition phenomenon of Ag-WC alloy has not been known yet, according to the experimental observations of the authors, re-ignition shows that the re-ignition occurs in the vacuum valve at the contact point / between contact points / contact point / arc shield. It occurs at a fairly high frequency between. Therefore, the authors have clarified the extremely effective technology for suppressing the re-ignition, such as the technology for suppressing the sudden gas emitted when the contact receives an arc and the technology for optimizing the contact surface morphology. Contributed to the suppression of the outbreak. For example, paying attention to the total amount of gas released during the heating process of Ag-WC alloy, the type of gas, and the release form, and observing the correlation with the occurrence of restriking in detail, it was found that it was a very short time near the melting point. However, in the contacts where a large amount of gas was suddenly released in a pulsed manner, the re-ignition rate was also high and the breaking characteristics were extremely deteriorated.

Therefore, it is necessary to remove the cause of sudden gas release in the Ag-WC alloy in advance, for example, by heating at a temperature higher than the melting temperature of Ag, or pores and structural segregation in the alloy of the Ag-WC alloy. By improving the sintering technology so as to suppress the occurrence of re-ignition phenomenon, the occurrence of re-ignition phenomenon was reduced and the breaking characteristics of the vacuum circuit breaker were improved. However, in recent years, as a result of increased use opportunities under severe conditions such as adaptation of voltage and current range and adaptation to diversifying loads, it is necessary to develop further new technology in addition to the above-mentioned conventional technology. Has become.

The present invention has been made to solve the above-mentioned conventional problems, and its purpose is to achieve the conventional Ag-W.
Lower cost than C contact material and conventional Ag-WC
It is an object of the present invention to provide a contact material for a vacuum valve that has both current cutting characteristics and interruption characteristics that surpass the characteristics of the contact material.

[0017]

[Means for Solving the Problems] As a result of repeated studies by the authors to achieve the above object, the feature of the first invention used for this is that TiC is 30 to 70% (volume%) as an arc-resistant component. 70 to 30% (volume%) of the conductive component made of Cu
[Cu-TiC] contact alloy composed of
The auxiliary component consisting of 0.0
[Cu-TiC] containing 05 to 0.75% (wt%)
+ Al-based vacuum valve contact material.

The feature of the second invention is that the arc-resistant component is
TiC having an average particle size of 0.1 to 10 μm is 30 to 7
0% by volume, 70 to 30% by volume of a conductive component made of Cu,
C in the size range of 0.01 to 5 μm and in the non-solid solution state or the compound non-forming state (hereinafter C) is
A [Cu-TiC-C] contact composed of 0.005 to 1.0% by weight with respect to the amount of TiC, and an auxiliary component of Al being 0.005 with respect to the amount of the arc resistance component. ~
It is a contact material for "Cu-TiC-C" + Al vacuum valve containing 0.75% by weight.

The characteristic feature of a preferred embodiment of the present invention is that [C
[C] in the non-solid solution state or the non-compound forming state in the [u-TiC] -based alloy, the gap L between the C particles is equal to or larger than the size d of the nearest C particles (L). ≧ d) and is highly dispersed and distributed in the [Cu—TiC] alloy.

A characteristic of another preferred embodiment of the present invention is that the stoichiometric ratio Ti: C of Ti carbide in the [Cu-TiC] alloy is 1: 1 to 1: 0.7 (TiC). ₁ to _0.7
The contact material for a vacuum valve is characterized in that

A feature of another preferred embodiment of the present invention is that a part or all of the Ti carbide in the [Cu-TiC] type alloy is replaced with v carbide (vanadium carbide: VC).

The characteristics of another preferred embodiment of the present invention include:
At least one of Sb and Te is contained in the Cu—TiC alloy in an amount of 0.05 to 0.5% (wt%). Another preferred embodiment of the present invention is characterized in that the auxiliary component consisting of Al is contained in a predetermined amount (amount of A1 which is finally required is 0.00
5% to 0.5% of all or part of A1 is Cu,
After preliminarily compounding or alloying with at least one of the constituent components consisting of TiC and C, the obtained compound, alloy or compound is converted into the above [Cu-TiC], [Cu
-TIC-C] + Al as a raw material for manufacturing a contact material for a vacuum valve.

As described above, the Ag-WC alloy is used as a contact that exhibits stable characteristics as a low cut contact material. However, it is necessary to further improve the above-mentioned demand for simultaneously improving the cutting property and the blocking property. Recent circuit breakers improve both characteristics at the same time,
Particularly in the cutting characteristics, it is extremely important to keep the value in a low range (good characteristics) even after opening and closing a predetermined number of times and to reduce the variation width.

When the external magnetic field (for example, the longitudinal magnetic field technology) is applied to the contacts of the vacuum valve, the current is interrupted, and the arc generated by the interruption is prevented from stagnating and concentrating in the low arc voltage portion. , Move on the contact electrode surface. When the [Cu-TiC-C] -based contact of the present invention is mounted on this vacuum valve, C in the alloy exists in the alloy in a non-solid solution state or a compound-free state, so that the material composition on the contact surface is Acts in the direction of averaging (uniformizing)
This contributes to reducing the variation width of the cutting characteristics. Furthermore, since C exists in the alloy in a non-solid solution state or a compound-free state, the arc on the contact electrode easily moves, which promotes the diffusion of the arc, thereby reducing the stagnation and concentration of the arc. As a result, the contact area that can handle the breaking current is substantially increased,
It also contributes to the improvement of blocking characteristics.

Further, since C exists in the alloy as a non-solid solution state or a compound-free state, arc stagnation and concentration are reduced, and as a result, local abnormal evaporation phenomenon of the contact electrode is prevented and surface roughness is prevented. The benefit of reduction is also obtained, which contributes to the improvement of wear resistance.

However, when the current value of a certain value or more is interrupted, the arc stagnates at one or more unpredictable points, abnormally melts, and reaches the interruption limit. In addition, the abnormal melting causes the metal Cu generated by the instantaneous explosive evaporation of the [Cu-TiC-C] -based contact material to significantly impair the insulation recovery of the vacuum circuit breaker that was in the opening process. It causes further deterioration. Further, the abnormal melting causes huge droplets to be formed, which causes the contact electrode surface to be roughened, resulting in deterioration of withstand voltage characteristics, increase in re-ignition occurrence rate, and abnormal consumption of materials.

As described above, it is not possible to predict where the arc causing these phenomena is stagnant on the contact electrode surface. Therefore, the contact condition is such that the generated arc can be moved and diffused without stagnating. It is desirable to give to. As a desirable condition, in this example, [Cu-T
The existing form of C (C content etc.) in the iC-C] + Al alloy was optimized and the Al content was optimized. As a result, Al
It was possible to further improve the cutoff property by the effect of addition of Al and achieve both the cutting property and the cutoff property by the synergistic effect of C and Al.

That is, Al is a [Cu-TiC] alloy, [C
In the [u-TiC-C] alloy, it mainly acts on Cu and participates in improving the blocking (blocking) characteristics. One of the factors that control the breaking characteristics is thermophysical properties such as thermal conductivity that controls the contact surface temperature. The decrease in conductivity causes the contact surface temperature to rise, and excessive steam is released at the moment of interruption,
It causes a decrease in the blocking performance. That is, Al in a predetermined amount range is
The effect of suppressing and reducing the rise in the equilibrium vapor pressure of Cu in the [Cu-TiC] alloy and the [Cu-TiC-C] alloy is exhibited, and as a result, it contributes to the improvement of the barrier property. Al
Is less than a predetermined amount, it is difficult to disperse Al uniformly,
There are large variations in the breaking characteristics. When the amount of Al is equal to or more than a predetermined amount, the conductivity of the [Cu-TiC-C] alloy is remarkably lowered, and thus the breaking current value is remarkably lowered (characteristic deterioration). The synergistic effect of the addition was also intended to improve the adhesion strength between the TiC particles and the C particles and to improve the organizational uniformity of Cu and TiC in the contact material.

As a result, not only is the control to preferentially preferentially reduce the amount of Cu that evaporates and scatters when an arc is received, but also re-ignition occurs on the contact surface due to thermal shock during arcing. However, the generation of cracks was suppressed, and TiC particles were prevented from falling off. Particularly, the amount of C in the non-solid solution state or the state of not forming a compound is 1.0% (% by weight) or less with respect to the amount of TiC, preferably 0.005 to
Optimized to 1.0% and its size 0.01-5
A after limiting to less than μm (diameter when converted to sphere)
1 was set as the optimum range. This contact alloy structure contributed to the improvement and stabilization of the cutting property and the stabilization and the improvement of the cutting property while minimizing the deterioration of the restriking property.

The amount of C in a non-solid-solution bear or compound-free state is preferably 0.005 with respect to the amount of TiC.
% Or more means that the cutting characteristic is particularly in the latter half of opening and closing (1990
This is because it is possible to suppress the tendency that the variation width during the opening and closing of 0 to 20000 times) slightly increases.

Although the "Cu-TiC-C] -based alloy has been mainly described above as a representative example, the effect of C and C and Al existing under the predetermined conditions has the same tendency even with respect to" Cu-TiC] + Al. obtain.

According to the experiments by the authors, [Cu-Ti
By optimizing the amount and size of C in C] and the amount of Al, it is possible to obtain a uniform distribution of Cu, TiC, and C in the alloy structure, adhesion strength of Cu, TiC, and C to each other. As a result of the improvements, even after receiving the arc, there will be less enormous traces of melting and spatter damage that are harmful to the re-ignition occurrence, and there will be less contact surface roughness that will have an important effect on the suppression of re-ignition. It was also useful for improving arc wear. The improvement of arc wear resistance has the effect of smoothing the contact surface, which is useful for reducing the variation width of the cutting and breaking characteristics even after opening and closing a large number of times. Due to these synergistic effects, the cutting property was improved and, at the same time, the barrier property and wear resistance of the [Cu-TiC] alloy were improved.

It is preferable that C existing in a predetermined ratio of [Cu-TiC] -based alloy is in a non-solid solution state or a compound non-forming state. If it is not in such a state, the cutting characteristics are stable after opening and closing a large number of times. In particular, the variation width tends to increase, and a large variation occurs in the breaking characteristic after opening and closing a large number of times.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below. [Cu-TiC] type contact and [Cu-T]
In a vacuum valve equipped with an [iC-C] system contact, Al as an auxiliary component improves the current cutoff property while maintaining the cutting property when the Al amount is increased to a predetermined amount.
When the amount of Al exceeds a predetermined amount, the cutoff characteristics rapidly deteriorate (deteriorate).

In the latter vacuum valve equipped with a [Cu-TiC-C] system contact, C as an auxiliary component is C
When the amount is increased up to a predetermined amount, the cutting property is further improved as compared with the former [Cu-TiC] system, but the breaking property is improved up to a predetermined amount of C, but when the amount exceeds the predetermined amount, it rapidly deteriorates. Shows the tendency of.

[Cu-TiC] -based contacts and [Cu-TiC]
As a general tendency of a vacuum valve equipped with a -TiC-C] -type contact, the latter [Cu-TiC-C] -type contact tends to be more advantageous than the former [Cu-TiC] -type contact in terms of cutting characteristics alone. Yes, the latter [Cu-TiC
The -C] type contact tends to be more advantageous. When considering the cutting characteristics and the cutoff characteristics at the same time, control of the Al amount and management of the existing form of C are important.

In this example, TiC (or VC) is adopted in place of the conventional arc-resistant component WC, and Cu is used as a conductive component to improve the contact material price. (Or VC) was found to be superior to WC.

Further, in this example, in order to simultaneously achieve the current cutting characteristics (low cutting and stabilization thereof) of the vacuum valve and improvement of the breaking characteristics, C existing in [Cu-TiC] is not solid-dissolved. State or compound-free state, and
The iC amount (VC amount when the arc resistance component is VC) is 0.
It is controlled within the range of 005 to 0.5 (% by weight), and the size thereof existing in the contact is controlled within the range of 0.01 to 5 μm (diameter when converted into a sphere), and the amount of Al is also controlled. The effect is obtained by controlling the amount to a predetermined amount. Therefore,
The important points are the existence form of C in the [Cu-TiC] -based contact material (average particle size and amount and the degree of dispersion thereof) and control of the Al amount. Below, the evaluation conditions that clarify the effect of this example,
The evaluation method is shown.

(1) Cutting characteristics Diameter 20 mm, thickness 4 mm, one is flat and the other is 50
A predetermined contact of mmR is mounted on a detachable vacuum circuit breaker for cutting current test. After exhausting to 10 −3 Pa or less and cleaning the contact surface by baking, discharge aging, etc., this device was opened at an opening speed of 0.8 m / sec. The cutting current value is 50 Hz through the LC circuit, and the circuit current having an effective value of 44 A is opening and closing (1 to 100 times opening and closing) and the latter period (1).
It was obtained by observing the voltage drop of the coaxial shunt inserted in series at the contact (during 9900 to 20000 times). In addition, the measurement result is a relative comparison with the value of the cutting current value of Example 2 as 1.0. The smaller the cutting current value and the smaller the variation range, the better the cutting characteristics.

(2) Breaking characteristics A flat contact having a surface roughness of 5 μm and a convex contact having the same surface roughness and a radius of curvature of 1OOR are opposed to each other. A vacuum degree of 10-3 Pa. Attached to the detachable vacuum shut-off experimental device exhausted below, 4
After applying 0 kg load, 7.2 kV-31.5 kA
Power on and off. When this charging and blocking were repeated 10 times, the occurrence of welding and restriking was evaluated and the blocking characteristics were judged. The test was stopped when welding or remarkable re-ignition was observed before the number of times of turning on and off reached 10.

(3) Arc wear resistance Each contact was mounted on a detachable vacuum circuit breaker, and after the baking, current, voltage aging and opening speed conditions of the contact electrode surface were kept constant, 7.2 kV, 4 The loss weight was determined from the surface roughness before and after 1,000 times of interruption of 4 kA to determine the arc wear resistance. Next, an example of the method used for manufacturing the contact material of this example will be described.

The method of manufacturing the contact material of this example is roughly classified as follows.
An infiltration method in which Cu or Cu-Al is melted and poured into a skeleton composed of TiC and C or TiC and C and Al, and a powder obtained by mixing TiC, C powder, Cu powder, and Al powder at a predetermined ratio is sintered. Alternatively, there is a sintering method of forming and sintering. In addition, Al as a raw material includes Cu and Ti in addition to metallic Al.
C) Even if it is a composite metal in which the surface of C powder is coated with Al,
Also, a mixed metal obtained by simply mixing Cu, TiC, C powder and Al may be used. It can be used as an Al source at the time of producing the alloy without any problem whether it is alloyed, does not form a compound, or is in a mixed state.

In this example, the amount of Al in the Cu-TiC alloy, which is one of the triggers for the re-ignition rate, and the state of presence of C (non-solid solution or compound-free state) (for example, its amount), Is made possible by making the cutting properties and the breaking properties compatible with each other. Therefore, the manufacturing method thereof is important because it affects the existing state of C in the alloy.

That is, in the embodiment of the present invention, the preferable TiC powder is, for example, the amount of C in a non-solid solution or non-compound state and its particle size by controlling the heat treatment temperature and time, atmosphere and the like. , T in the range of (TiC ₁ to _0.7 ) stoichiometrically while adjusting the particle size distribution.
Select iC. The particle size and particle size distribution were adjusted by using mechanical pulverization and sieving together.

In this example, the amounts of C and Al must be controlled within a very small range. As a technique for controlling the range of an extremely small amount of C (non-solid solution or compound non-formation state),
While controlling the atmosphere and temperature of the above TiC powder,
Other than the method of heat treating iC to partially decompose or reprecipitate it, for example, when a certain organic substance is thermally decomposed together with TiC, a minute amount of C is decomposed by utilizing the decomposed and precipitated C on the TiC surface. It can be obtained while controlling.
In addition, a method of depositing a C sputtered film on the surface of TiC and then using this as the raw material TiC was also selected. Similarly, the control of the extremely small amount of Al was similarly performed by sputtering Al on the surfaces of Cu and TiC and performing ion plating.

The amount and size of C (non-solid solution or compound-free state) in this [Cu-TiC] alloy has a small effect on the cutting property as the C content increases, but the blocking property tends to deteriorate. It is in. Note that Ti in the [Cu-TiC] alloy
Similarly, when the total amount of C is increased, the blocking characteristic tends to be deteriorated.

The amount of Al is [Cu-TiC] alloy, [Cu
-TiC-C] alloys improve the barrier properties, but excessive presence rapidly degrades the barrier properties. [Cu-TiC]
The method for producing the alloy is such that when the amount of C and the amount of Al are TiC
The amount of Cu and Cu is extremely small compared to the amounts of Cu and Cu, so improving the homogeneity of mixing is an important technical issue. As a means for improving the homogeneous mixing property, in this example, for example, an extremely small amount of TiC and C powder or Al powder taken out from a part of the finally required TiC amount (30 to 70% by volume) are used. (Preferably approximate volume) mixed (if necessary Bi, Sb, T
At least one of e may be added) to obtain a primary mixed powder (this is repeated until the nth mixing if necessary).

This first-order mixed powder (or n-th order mixed powder)
And the remaining TiC powder are mixed again, and finally [TiC, C] powder, [TiC, Al] in a sufficiently good mixed state.
Powder, [TiC, C, Al] powder is obtained. This [TiC,
C] powder or [TiC, Al] powder, [TiC, C, A
l] powder and a predetermined amount of Cu powder are mixed, and then, in a hydrogen atmosphere (even in vacuum), for example, sintering at a temperature of 930 ° C. and pressurization are combined once or a plurality of times to obtain [Cu- TiC
-C] contact material (or [Cu-TiC] + Al, [C
u-TiC-C] + Al contact material) was manufactured (hereinafter represented by [Cu-TiC] + Al) and processed into a predetermined shape to form a contact (manufacturing example 1).

As another alloying method, conversely, a very small amount of Cu and Al powder (or C powder, or both) taken out from a part of the finally required Cu amount (preferably approximated). Volume) is mixed (Bi is added if necessary) to obtain a primary mixed powder (this is repeated until the n-th mixing if necessary). This primary mixed powder (or n-th mixed powder) and the remaining Cu powder are mixed again to finally obtain [Cu, C] powder in a sufficiently good mixed state. This [Cu, C]
After mixing the powder and a predetermined TiC powder (finally necessary TiC amount), in a hydrogen atmosphere (possible even in vacuum), for example, 94
[Cu-TiC-C] contact material or [Cu-T] by combining sintering at 0 ° C and pressurization once or multiple times.
iC-C] + Al contact material was manufactured (manufacturing example 2).

As another manufacturing method, the nth-order mixed [TiC, C] powder or [TiC, C, A] manufactured by the above method is used.
l] powder is sintered at a temperature of 1200 ° C. to prepare {TiC, C} skeletons and {TiC, C, Al} skeletons having a predetermined porosity, and Cu (Bi if necessary Bi
Is also added), for example, at a temperature of 1150 ° C., and [Cu-
TiC-C] contact material or [Cu-TiC-C] + A
An l-contact material was manufactured (manufacturing method example 3).

As another alloying method, [Ti
C, C] powder or [TiC, C, Al] powder at 1000 ° C
At a temperature of 1 to produce a skeleton having a predetermined porosity, and separately prepare Cu in the pores at, for example, 1150 ° C.
At the temperature of [Cu-TiC-C] contact material, [Cu
-TiC-C] + Al contact material was manufactured (Production Example 4).

As another alloying method, a physical method using an ion plating device or a mechanical method using a ball mill device is used, and C is added to the surface of Ti powder (TiC powder or Cu powder may be used). C-coated Ti powder coated (and optionally Bi at the same time) was obtained, and this C-coated Ti powder and Cu
After mixing with powder (Bi is added at the same time if necessary), in a hydrogen atmosphere (even in vacuum), for example, sintering at a temperature of 1050 ° C. and pressurization are combined once or a plurality of times, and [C
[u-TiC-C] contact material was produced (Production Example 5a).

As another alloying method, a physical method using an ion plating device or a mechanical method using a ball mill device is used, and Al is applied to the surface of Ti powder (TiC powder or Cu powder may be used). After obtaining Al-coated Ti powder coated (and also Bi if necessary), and mixing the Al-coated Ti powder and Cu powder (adding Bi at the same time if necessary),
In a hydrogen atmosphere (even in vacuum), for example, sintering at a temperature of 1050 ° C. and pressurization are combined once or plural times,
A [Cu-TiC-C] + Al contact material was produced (Production Example 5b). As another alloying method, especially in the technique of uniformly mixing Cu powder, TiC powder, C powder, and Al powder, an oscillating motion is performed. The method of superposing the stirring motion with the stirring motion is also useful. As a result, the mixed powder does not have the phenomenon of becoming agglomerates or agglomerates, which is generally found when using a solvent such as acetone, and the workability is improved. Further, if the ratio R / S of the stirring number R of the stirring motion of the stirring container in the mixing work and the shaking number S of the shaking motion given to the stirring container is selected within a preferable range of about 10 to 0.1, the solution is obtained. The energy input to the powder during crushing, dispersing, and mixing is in a preferable range, and it has a feature that the deterioration and contamination of the powder during the mixing operation can be suppressed to a low level.

Although the action of crushing the powder is added in the case of mixing and pulverizing with a conventional smelting machine or the like, in the present method in which the rocking motion and the stirring motion are superposed, the R / S ratio is approximately 10%.
Since it is distributed to about 0.1, the powder is mixed to the extent that the powder particles are entangled with each other and has good air permeability, so that the sinterability is improved and a high-quality molded body or sintered body or skeleton is obtained. Furthermore, there is no excessive energy input and the powder does not deteriorate. If the mixed powder in such a state is used as a raw material, the alloy after sintering and infiltration can be reduced in gas, which contributes to stabilization of cutting characteristics and barrier performance (Production Example 6).

In the case of [Cu-VC-C], the same manufacturing method is selected, and [Cu-TiC] + Al contact material, [Cu-Ti]
C-C] + Al contact material can be manufactured. In Examples and Comparative Examples of the present invention, which will be described later, these methods are appropriately selected and adopted, and a contact material exhibiting the effect of the present invention can be obtained by selecting any technique.

FIG. 1 shows an example of the embodiment of the present invention.
Will be described with reference to the evaluation conditions shown in the table and the evaluation results shown in the table of FIG.

First, the outline of the assembly of the experimental valve for the shutoff test will be described. Prepare a ceramics insulation container (main component: Al ₂ O ₃ ) whose end surface is polished to an average surface roughness of about 1.5 μm, and subject this ceramics insulation container to preheating treatment at 1650 ° C. before assembly. did. The main component of the ceramic insulation container is no problem even in the Si0 _2.

42% N with a plate thickness of 2 mm as a sealing metal fitting
An i-Fe alloy was prepared.

As a brazing material, 72% A with a thickness of 0.1 mm
A g-Cu alloy plate was prepared.

The above-prepared members are arranged between the objects to be joined (the end surface of the ceramic insulating container and the sealing metal fitting) so that airtight bonding can be performed, and 5 × 10 ⁻⁴ Pa. In a vacuum atmosphere, the sealing metal fitting and the ceramic insulating container are subjected to a hermetically sealing process.

Next, Tables 1 and 2 show the contents of the test contact material, the evaluation contents and the results.

Examples 1-3 and Comparative Examples 1, 2 15-85% (% by volume) with an average particle size of 1.3 μm
TiC _1.0 powder, 0.05% (wt%) as an auxiliary component
Of the Al and C particles of L> d (where L is the gap between two C particles or C groups that re-adjacent to each other, d is the diameter of the smaller C particle or the smaller C group) .)
The Cu-TiC alloy described above was appropriately selected or combined with the above-mentioned manufacturing methods 1 to 6, and the amount of Al was set to 0.05% by weight [Cu-15 to 85% by volume TiC] + Al.
A contact material made of alloy was manufactured. A test piece obtained by processing these materials into a predetermined shape having a thickness of 3 mm and an average surface roughness of the contact surface of 0.3 μm was obtained, and the cutting property, the blocking property, and the wear resistance were measured. Evaluation conditions) and Table 2 (results) are shown. Note that, in the present invention, TiC and the balance of Cu are set to volume% for convenience, and other elements are set to weight% (ratio to the amount of TiC) because they are convenient in operation.

The amount of TiC is set to 30 to 70% by volume [Cu
In the -TiC] + Al alloy, all of the cutting characteristics, the interruption characteristics, and the wear resistance characteristics exhibit good characteristics (Examples 1 to 3).

That is, the cutting characteristic is 1 when the circuit having an effective value of 44 A is used.
The average value (0.95 to 1.3) and maximum value (1.05 to 1.4) of the cut value of 100 times (initial opening and closing) during opening and closing of 100 times
The value of 5) is close and stable. Similarly 199
The range between the average value and the maximum value of the cut values of 100 times (the latter half of the opening and closing) of the opening and closing times of 2000 to 20000 times is small and stable, which shows a favorable state bear. Furthermore, there is little change in the cutting value between the initial stage of opening and closing and the latter stage of opening and closing, and it is stable.

Apply 7.2 kV-31.5 kA 10 times.
The interruption characteristics when interrupted are judged to be "passed" with success of interruption without occurrence of restriking and welding.

7.2 kV-4.4 kA was cut off 1000 times, and the weight change (weight loss) of the contact points before and after the interruption was measured and evaluated as the wear resistance characteristic (the weight loss value of Example 2 was 1.
0), the relative value compared with Example 2 is
It was in the range of 1.0 to 1.25 and showed stable consumption characteristics.

On the other hand, when the same evaluation was carried out on a [Cu-TiC] + Al alloy (comparative example 1) in which the amount of TiC was 15% by volume and the balance was Cu, the breaking characteristic was 7.2 kV-31. Although 0.5 kA was applied 10 times and slight welding was observed about 2 times during the interruption, the interruption was successful without any problem in practical use. However, the wear resistance was greatly increased by 5.2 times (deterioration of characteristics) as compared with Example 2 as a standard, as compared with Example 2 as a comparison target. The cutting characteristics showed a variation in the maximum value.

Further, the amount of TiC is set to 80% by volume and the balance is C
When [Cu-TiC] + Al alloy (Comparative Example 2) with u was subjected to the same evaluation, the opening / closing initial stage (1 to 1)
The cutting current value during the opening and closing of 00 times) and the latter half of the opening and closing (while opening and closing the 19900 to 20000 times) showed extremely good characteristics equal to or higher than the characteristics of Example 2 as a standard. The weight loss before and after the interruption shown was about 1.3 times as great as that of Example 2, and was within the allowable limit. However, a significant crack was generated on the contact surface after the interruption. Due to the surface deterioration of
When kA was turned on and off 10 times, re-ignition was observed about 3 times, and the interruption characteristic was judged to be “fail”. According to the result of the microscopic observation, scattered spots of absent Cu, TiC agglomeration and TiC detachment were found on the contact surface.

Therefore, in order to obtain a balance between the cutting property, the blocking property and the wear resistance, the addition of Al in the [Cu-TiC] alloy in the range of the TiC amount of 30 to 70% by volume shown in Examples 1 to 3 was performed. The effect is exerted effectively.

Examples 4 to 8 and Comparative Examples 3 to 4 In the above Examples 1 to 3 and Comparative Examples 1 and 2, [Cu-T
The presence effect of Al in the [iC] -based alloy is shown in the case where the average particle size of TiC (diameter when the particles are spherical) is 3 μm.
The average particle size is not limited to 3 μm.

When the average particle size of TiC is 0.01 to 10 μm, the cutting property, the blocking property, and the wear resistance property are all excellent (Examples 4 to 8).

That is, the cutting characteristic is 1 when the circuit having an effective value of 44 A is used.
The width of the average value (1.0 to 1.5) and the width of the maximum value (1.15 to 100) of opening and closing 100 times (initial opening and closing) during opening and closing 100 times
1.55) is small and stable. Similarly from 1900
The width of the average value (1.2 to 1.4) and the maximum value (1.3 to 100) of the cut value during the opening and closing of 20000 times (late opening and closing)
1.9) is also small and stable, showing a preferable state.
Furthermore, the change in the cutting value between the early stage of opening and closing and the latter stage of opening and closing is small and stable.

Applying 7.2 kV-31.5 kA 10 times,
The interrupting characteristic when interrupted is that the interrupting is successful without the occurrence of re-ignition and the occurrence of welding, and is judged as "pass". See also 7.2
In the evaluation of the wear resistance characteristics by measuring the change in weight (weight loss) of the contact before and after kV-4.4 kA was cut off 1000 times (weight loss value of Example 2 was 1.0), The relative value compared with Example 2 was in the range of 0.9 to 1.3, and showed stable consumption characteristics.

On the other hand, the average grain size of TiC is 0.0
When the thickness is 1 μm or less (Comparative Example 3), the average cutting value (1.1) of 100 times of opening and closing (opening and closing) 100 times (initial opening and closing)
The maximum value (1.25) is small and stable. But,
From the viewpoint of manufacturing cost, it is not preferable to mass-produce the [Cu-TiC] + Al alloy containing TiC having an average particle diameter of 0.01 μm or less with a contact material having a constant thickness on an industrial scale ( The cutting property, the blocking property, and the wear resistance test in the latter stage of opening and closing) were stopped (Comparative Example 3). Further, when the average particle size of TiC is set to 25 μm (Comparative Example 4), the average value (2.05) and the maximum value (2.35) of the cutting values at the initial stage of opening and closing show a tendency of slightly increasing. In particular, the maximum value of the cutting characteristics in the latter half of opening and closing tends to increase remarkably (6.55, which shows instability in the cutting characteristics due to the number of opening and closing operations.
Variations were observed in the breaking characteristics, such as frequent occurrence of unbreakable state in A, and it was judged as "fail", and there were variations in the contact resistance characteristics.

Examples 9-11, Comparative Examples 5-6 In the above Examples 1-8 and Comparative Examples 1-4, [Cu-Ti
C] The presence effect of Al, which is the main object of this example when the amount of TiC in the alloy and the average particle diameter of TiC are controlled to keep the amount of Al constant at 0.05%, is shown below. The effect of the presence of Al is exhibited without limiting the amount of Al to 0.05%. That is, when the same evaluation was carried out with the amount of Al being 0.005% to 0.75%, in the case of [Cu-TiC + Al] alloy with the amount of TiC being 50% by volume, any of cutting properties, interruption properties, and wear resistance properties was observed. The peach exhibits good characteristics (Examples 9 to 11).

That is, as for the cutting characteristic, the circuit having an effective value of 44 A is set to 1
Width of average value of cut values (1.1 to 1.25) and width of maximum value (1.15 to 100) during opening and closing 100 times (initial opening and closing)
1.3) is small and stable. Similarly from 1900
The average value (1.2 to 1.35) of the cut values and the maximum value range (1.3 to 1.
The width of 5) is also small and shows a stable and preferable state.
Furthermore, the change in the cutting value between the early stage of opening and closing and the latter stage of opening and closing is small and stable.

Applying 7.2 kV-31.5 kA 10 times,
The interruption characteristics when interrupted were judged to be “passed” with success of interruption without occurrence of re-ignition and welding.

Also, in the evaluation of the wear resistance characteristics by breaking the 7.2 kV-4.4 kA 1000 times and measuring the weight change (weight loss) of the contact before and after that, the relative value compared with Example 2 was , 0.95 to 1.0, showing extremely stable consumption characteristics. On the other hand, the amount of Al is 0.0
The same evaluation was carried out on an alloy of 50% by weight TiC and the balance Cu which is less than 05% (Comparative Example 5).
Both the cutting characteristics and the wear resistance characteristics were extremely stable and desirable characteristics, but before the test at 7.2 kV-31.5 kA, 25 kA interruption had already occurred, so many interruptions were impossible.
The input of 7.2 kV-31.5 kA and the breaking test could not be conducted, and the breaking characteristic was judged to be "fail". Therefore,
The effect of the presence of Al on the improvement of the barrier property of the [Cu-TiC] alloy is not sufficiently exhibited when the Al content is 0.005% or less.

Further, 50% by weight of Ti with Al content of 5%
When the same evaluation was carried out on an alloy of C and the balance Cu (Comparative Example 6), the cutting characteristics and the wear resistance characteristics were very stable and preferable, as in Comparative Example 5, but 7.2
Before the test of kV-31.5kA, with the interruption of 20kA, it was already impossible to cut off, so 7.2kV-3
The 1.5 kA injection / interruption test could not be performed, and the interruption characteristics were judged to be “fail”.

The effect of the presence of Al on the improvement of the barrier properties of the [Cu-TiC] alloy is that when the Al content is 5%, the barrier properties of the [Cu-TiC] alloy are significantly reduced due to a significant decrease in the conductivity of the material. It has been found that there is no effect to improve. Therefore, Al for improving the barrier property of the [Cu-TiC] alloy has an Al content in the range of 0.005 to 0.75% by weight, while maintaining the cutting property and the wear resistance property. The blocking characteristic can be improved.

Examples 12 to 15 and Comparative Example 7 In the above Examples 1 to 11 and Comparative Examples 1 to 16, [Cu-T
iC] As a measure for improving the breaking characteristics of alloys,
The presence effect of 1 was shown. The effect of the presence of Al, which is the main object of this example, is that [C-TiC] alloy is used in addition to [C
The effect is exhibited also for the [u-TiC-C] alloy. In the [Cu-TiC] alloy, 0.005 to 1.0% (% by weight) of C in a non-solid solution state or a compound-free state was contained as a constituent component of the alloy [Cu
In the -TiC-C] + Al alloy, the same or more favorable effects were exhibited (Examples 12 to 15).

The TiC content was 50% (volume%), the average particle diameter was kept constant at 3.0 μm, and the C content was 0.005%-.
[Cu-TiC-C] + Al with 1.0% (wt%)
The alloy exhibits good cutting properties, blocking properties, and wear resistance properties (Examples 12 to 15). That is, the cutting characteristics are such that the circuit having an effective value of 44 A is opened and closed 1 to 100 times, and the width of the average cutting value is 100 times (initial opening and closing) (0.8
5 to 1.0) and the maximum value width (1.1 to 1.25) are small and stable. Similarly, the range of the average value of the cut values of 100 times (late opening and closing) during the opening and closing of 19,900 to 20,000 times (1.
1 to 1.25) and the maximum width (1.25 to 1.45)
Has a small width and is stable, and both are in a preferable state. Further, the change in the cutting value between the initial stage of opening and closing and the latter stage of opening and closing is small, and it is stable with respect to the number of times of opening and closing.

Applying 7.2 kV-31.5 kA 10 times,
The interruption characteristics when interrupted were that the interruption was successful without re-ignition or welding. Also 7.2kV-4.4k
In the evaluation of the wear resistance characteristic by measuring the weight change (weight loss) of the contact point before and after A was interrupted 1000 times (weight loss value of Example 2 was 1.0), Example 2 was also used.
The relative value compared with that was in the range of 1.0 to 1.2, indicating extremely stable consumption characteristics. On the other hand, [Cu-
In the TiC] alloy, when the amount of C in the non-solid solution state or the compound-unformed state is set to 5.5%, the cutting property is 1 to 100 times of opening and closing, and the range of the average cutting value of 100 times (initial opening and closing). The width of the maximum value (0.75) (0.95) is small and stable. Similarly, the range of the average cutting value of 100 times (later opening and closing) during opening and closing from 19,900 to 20,000 times (0.9
The width of 5) and the width of the maximum value (1.1) are also small and stable, showing a preferable state. Furthermore, the change in the cutting value between the early stage of opening and closing and the latter stage of opening and closing is small and stable.

However, before the test of 7.2 kV-31.5 kA proceeded, it was already impossible to cut off at the cutoff of 7.2 kV-20 kA. Therefore, the test of 7.2 kV-31.5 kA was not applied and the cutoff test was not conducted. The breaking characteristic was judged to be “fail”.

Also, in the wear resistance characteristics in which the weight change (weight loss) of the contact point before and after the interruption of 7.2 kV-4.4 kA 1,000 times was measured, the weight loss value of Example 2 was set to 1.0. The relative value compared to Example 2 is 4.6.
And the consumption characteristics were unfavorable (Comparative Example 6).

As described above, the main effect of this example is to improve the barrier property by adding Al, not only for the [Cu-TiC] alloy but also for the amount of C in the non-solid solution state or the compound-free state of 0.005. Controlled to the range of 0.75% [Cu
It was effectively exhibited both in the -TiC-C] alloy and in the [Cu-TiC-C] + Al alloy to which Al was added under the predetermined conditions (Examples 12 to 15).

Examples 16 to 17 and Comparative Example 8 In Examples 1 to 15 and Comparative Examples 1 to 8 described above, in the alloy using TiC _1.0 as the stoichiometric ratio of Ti and C, [Cu -TiC] alloy, [Cu-TiC-
The presence effect of Al, which is the main object of this example, was shown for the C] alloy. The titanium carbide used in this example is TiC _1.0.
It can be implemented without limitation. As TiC, Ti
Similar effects were exhibited with C _0.95 and TiC _0.70 (Examples 16 to 17). That is, when the same evaluation as the above was carried out, the cutting characteristics were 1.15 to 1.3 in the initial stage of opening and closing (while opening and closing 1 to 100 times), and the latter period of opening and closing (19900 to
Even during opening and closing 20000 times), the range was 1.25 to 1.5, which was within the allowable range. The breaking characteristic is also 7.2.
The interruption characteristics when kV-31.5 kA was turned on and off 10 times were judged to be interruption [pass] without re-ignition or welding. Wear resistance (7.2kV, 4.4kA
(The change in weight after 1000 times of interruption) was 1.0, and the wear characteristics were 1.0 times as much as the standard wear. As described above, all of them exhibit almost the same good characteristics (Example 16).
~ 17).

On the other hand, when the titanium carbide of TiC _0.55 (Comparative Example 18) was used as a raw material as a stoichiometric ratio of Ti and C, the cut value at the initial stage of opening and closing was:
The average value (1.5) and the maximum value (1.85) show the allowable range, but the cutting characteristics in the latter half of the opening and closing show the average value (2.35) and the maximum value (2.85). , There was a tendency to increase in the latter half. The wear resistance was about 1.2 times, but the target of the cutoff characteristics was 7.2 kV.
Before proceeding to the -31.5 kA test, there were variations in the blocking characteristics, such as frequent failure of blocking at 25 kA, and it was judged as "fail" (Comparative Example 8).

Examples 18 to 21, Comparative Example 9 In the above Examples 1 to 17 and Comparative Examples 1 to 8, [Cu-Ti
Although the size of C in the C] alloy and the [Cu-TiC-C] alloy was not particularly controlled, the [Cu-TiC] alloy,
In order to sufficiently exert the effect of Al addition to the [Cu-TiC-C] alloy, the size of C existing in the alloy in a non-solid solution state or a compound-free state (grain size of C, C Refers to the group when they are agglomerated. When C is indefinite, it is also indicated by the diameter when the indefinite form is converted into a sphere). Was found.

That is, the size of C in the alloy is 0.01-5.
In the case of μm (Examples 18 to 21), while maintaining the cutting characteristics and the wear resistance characteristics in the preferable ranges, the effect of Al addition was sufficiently exerted, and when 7.2 kV-31.5 kA was turned on and off 10 times. The breaking characteristics of the test piece were "passed" without re-ignition and welding. However, when the size of C in the alloy is 25 μm (Comparative Example 9), the cutting characteristics show an average value of 0.9 and a maximum value of 1.8 at the initial stage of opening and closing (during 1 to 100 times of opening and closing), which is a problem. There was not, but late opening and closing (1990
After opening and closing 0 to 20,000 times), the average value increased to 2.5 and the maximum value increased to 3.45 (deterioration of characteristics), and the wear resistance (7.2 kV, 4.4 kA) was cut off 1000 times. (Weight change), the consumption of Example 2 which is the standard is 1,0
The consumption rate reached 6.3 times, and showed a large increase in consumption (characteristic deterioration) and 7.2 kV-31.5.
In the interruption test that turns on and off kA 10 times, 1
Occurrence of re-ignition was observed about 5 times during the turning-on and turning-off of 0 times, and it was judged that the turning-off was "fail" (Comparative Example 9).

[Cu-TiC] alloy, [Cu-T]
The synergistic effect of simultaneously presenting Al and C as auxiliary components in the [iC-C] alloy is a significant improvement in the welding resistance. That is, [Cu-TiC] + Al and [Cu-TiC-
With C] + Al, when 7.2 kV-31.5 kA is cut off, both are present simultaneously [Cu-TiC-
Compared to the former [Cu-TiC] + Al, C] + Al has a welding detachment force at the time of welding reduced by about 20% to 30%, which contributes to downsizing of the device.

On the other hand, the characteristics of the [Cu-TiC] + Al alloy in which the auxiliary component in the [Cu-TiC] alloy is only Al are:
1 and C were compared with [Cu-TiC-C] + Al, which was present at the same time, and the rate of occurrence of re-ignition was observed when the above-mentioned 7.2 kV-31.5 kA 10-time closing and interruption test was further continued. There is a margin in the blocking performance. Therefore, whether to use only Al as the auxiliary component or to use both Al and C can be appropriately selected according to the purpose.

According to the result of microscopic observation, in Comparative Example 9 in which the average particle size of C was 25 μm, there were agglomeration of C and a lacking portion of C on the contact surface.

Examples 22 to 24, Comparative Example 10 In the above Examples and Comparative Examples, addition of Al under the above-mentioned predetermined conditions to the [Cu-TiC] -based contact material and the [Cu-TiC-C] -based contact material. Show that it is beneficial for improving the blocking characteristics. In addition, in the [Cu-TiC-C] -based contact material, it was shown that the existing form of C existing in the alloy in the non-solid solution state or the compound-free state also affects the improving effect of the Al barrier property. . In Examples 12 to 21 and Comparative Examples 7 to 9, the dispersity of C in the alloy (the closest C
(The distance between particles) is such that the distance L between the two closest C particles or C aggregates is greater than or equal to the smaller diameter d of the two C particles or C aggregates (L > D) symbol; X). However, the effect of the presence of Al in this example is not limited to the above-mentioned X, and the effect of improving the blocking property is obtained (hereinafter, C particles include C aggregates).

That is, as the dispersity of C, the interval L between the two C particles closest to each other is L> d such that the distance C between the two C particles is larger than the diameter d of the smaller C particle. In case (symbol; X), the distance L between the two closest C particles is equal to or larger than the diameter d of the smaller C particle of the two C particles, and L ≧ d In the case (symbol: Y), the distance L between the two closest C particles is separated by less than the diameter d of the smaller C particle of the two C particles L <d
In each case (symbol: Z), the same evaluation was performed.

As a result, in the case of X, X to Y, YZ,
After maintaining the cutting characteristics and wear resistance characteristics at desirable values,
The breaking characteristics when 7.2 kV-31.5 kA was applied and cut off 10 times were also "passed" with no interruption of re-ignition or welding (Examples 22 to 24). However, when the distance L between the two closest C particles is L <d compared with the diameter d of the C particles (symbol; Z), the cutting characteristics were in the preferable value range, but Consumable (7.2 kV, 4.
The weight change after interrupting 4 kA 1000 times) reached 2.4 times the consumption rate when the standard consumption of Example 2 was 1, 0, indicating an increase in consumption (characteristic deterioration). At the same time, in a breaking test in which 7.2 kV-31.5 kA was turned on and off 10 times, re-ignition was observed about 4 times during 10 times making and breaking, and it was judged as “fail” ( Comparative Example 9). On the contrary, when the dispersity of C is such that the distance L between two adjacent C particles is close to or less than the diameter d of the smaller C particle of the two C particles, L ≦ d (symbol; In (Z), the characteristics were significantly deteriorated, which was not preferable (Comparative Example 11).

Examples 25 to 26 In Examples 1 to 24, the case where titanium carbide (TiC) was used as the arc resistant component in the contact alloy was shown, but in the present invention, a part or all of TiC is used. Even if it is replaced with vanadium carbide (VC), exactly the same characteristic effects can be obtained.

Examples 27 to 29 [Cu-TiC] + Al and [Cu-TiC-C] + A
In the alloy in which a predetermined amount of Bi, Te, and Sb were added to 1, the amount of the alloy was 7.2 kV-3 as compared with the standard material of Example 2.
Welding removal force is about 1 when 1.5kA is cut off.
It was reduced to / 2-1 / 5 and contributed to downsizing of the device (Examples 27-29).

[0099]

As described in detail above, according to the contact material for a vacuum valve of the present invention, as an auxiliary component to the [Cu-TiC] type alloy and the [Cu-TiC-C] type alloy. By adding Al, [Cu-TiC] + Al alloy,
Since it is made of [Cu-TiC-C] + Al alloy, the breaking property can be improved while maintaining the cutting property and the wear resistance property at a preferable value, and the performance as the contact material can be greatly improved. .

Particularly, in the [Cu-TiC-C] + Al alloy, the stoichiometric morphology, the size of TiC (average particle diameter), and the non-solid solution state or compound in the [Cu-TiC-C] type alloy. While controlling the amount of C existing in the non-formed state, the size of C, and the dispersity of C within a preferable range,
By alloying Al as an auxiliary component, a stable material can be obtained and the stability of contact characteristics can be improved.

Further, by optimizing the amount of C and the gap between C particles in the non-solid solution state or the compound non-forming state, Cu which is selectively evaporated and scattered when an arc is received as a result is obtained. Not only control to reduce the number, but also it is possible to suppress the generation of significant cracks on the contact surface due to the re-ignition due to the thermal shock at the time of arcing, and reduce the scattering and dropping of TiC particles. can do.

As described above, since the alloy structure is improved to be uniform, the contact surface is less melted and scattered even after it is subjected to an arc, and the contact surface is roughened, which has an important effect on the suppression of re-ignition. It is possible to improve the arc wear resistance by reducing the amount, and it is possible to improve the breaking property while maintaining the cutting property and the wear resistance property.

[Brief description of drawings]

FIG. 1 is a table showing a list of respective evaluation conditions of examples and comparative examples of a contact material for a vacuum valve of the present invention.

FIG. 2 is a table showing a list of evaluation results of examples and comparative examples of the vacuum valve contact material of the present invention.

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Atsushi Yamamoto 1st Toshiba Town Fuchu-shi, Tokyo Inside Toshiba Fuchu Factory Co., Ltd. (72) Inventor Kansei Kei 1st Toshiba Town Fuchu-shi Tokyo Toshiba Fuchu Factory Co., Ltd. (72) Inventor Iwao Oshima No. 1 in Toshiba Town Fuchu, Tokyo Fuchu factory (72) Inventor Mitaka Honma No. 1 in Toshiba Town Fuchu, Tokyo Tokyo Fuchu factory (72) Inventor Hiromichi Somei, 1st floor, Toshiba Town, Fuchu City, Tokyo (56) References Japanese Patent Laid-Open No. 5-230565 (JP, A) Japanese Patent Laid-Open No. 4-206121 (JP, A) Japanese Patent Laid-Open No. 8-264082 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01H 33/66

Claims (6)

(57) [Claims] 1. An arc-resistant component made of TiC having a content of 30 to 70% by volume and a conductive component made of Cu having a content of 70 to 30% by volume. For the amount of arc component,
A contact material for a vacuum valve, which contains 0.005 to 0.75% by weight. 2. As an arc-resistant component, TiC having an average particle diameter of 0.1 to 10 μm is 30 to 70% by volume, a conductive component made of Cu is 70 to 30% by volume, and a size thereof is 0.01 to 5.
C in the range of μm and in a non-solid solution state or a compound-free state (hereinafter C) is composed of 0.005 to 1.0% by weight with respect to the amount of TiC [Cu- T
iC-C] contact material, wherein the auxiliary component made of Al is contained in an amount of 0.005 to 0.75% by weight based on the amount of the arc resistant component. 3. The Cu and TiC and an alloy formed by adding Al to these, or the Cu, TiC and C
And the gap L between the C particles in C in the non-solid solution state or the non-compound forming state in the alloy formed by adding Al to these is equal to the size d of the most adjacent C particles, or The contact material for a vacuum valve according to claim 1 or 2, wherein the contact material is made larger and is highly dispersed and distributed in the alloy. 4. The Cu and TiC and an alloy formed by adding Al to these, or the Cu, TiC and C
And the stoichiometric ratio Ti: C of Ti carbide in the alloy formed by adding Al to these is 1: 1 to 1: 0.
7. The vacuum valve contact material according to claim 1, wherein the contact material is in the range of 7. 5. The Cu and TiC and an alloy formed by adding Al to these, or the Cu, TiC and C
5. A vacuum valve according to any one of claims 1 to 4, characterized in that a part or all of the Ti carbide in the alloy formed by adding Al to these is replaced with VC which is vanadium carbide. Contact material. 6. As the auxiliary component Al, all or part of the finally required amount of Al is Cu, TiC,
6. A composite, an alloy or a compound which has been previously compounded or alloyed with at least one of the constituent components of C is used.
The contact material for a vacuum valve described.