JP2001236864A - Contact material of vacuum circuit-breaker for electric power - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact material of a vacuum circuit-breaker for electric power, that has stabilized reignition characteristics of Cu-Cr alloy and has superior current breaking characteristics. SOLUTION: For this contact material of a vacuum circuit-breaker for electric power, made of a Cu-Cr alloy, the hardness value of Cr particles in the Cu-Cr alloy is indicated as Hs and hardness value of Cu phase is set to Hm after sintering process or after sintering-infiltration process, and hardness value of Cr particles in the Cu-Cr alloy is indicated by Hr and hardness value of Cu phase as Ho, when the material is heated to the temperature directly under the melting point of Cu phase in the Cu-Cr alloy and is cooled to the normal temperature. In this case, the ratio [Hs/Hr] is set to be within the range of 1.0-1.6, and the ratio [Hm/Ho] is set to be within the range of 1.0 to 2.0. In this way, reignition characteristics and current breaking characteristics can be made to stabilize.

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 circuit breaker for electric power comprising a vacuum valve and the like having excellent breaking characteristics and restriking suppressing characteristics.

[0002]

2. Description of the Related Art The contacts of a vacuum valve for interrupting a current in a high vacuum by utilizing arc diffusivity in a vacuum are composed of two fixed and movable contacts facing each other.

In a vacuum circuit breaker, in addition to the three basic requirements of large current interruption performance, withstand voltage performance and welding resistance performance, suppression of occurrence of restriking is an important requirement.

[0004] However, since some of these requirements are contradictory, it is impossible to satisfy all the requirements with a single metal species. For this reason, in many contact materials that are in practical use, by combining two or more types of elements that complement each other for insufficient performance, specific contact points such as for large current and high withstand voltage can be obtained. Although a selection and adoption of a contact material suitable for the application has been made and a vacuum valve having excellent characteristics has been developed, a vacuum valve which sufficiently satisfies the increasing demand has not yet been obtained.

[0005] For example, a Cu-Cr alloy containing about 50 wt% of Cr (Japanese Patent Publication No. 45-35101) is known as a contact for the purpose of breaking large current. This alloy realizes high-voltage large-current disconnection by the effect that Cr itself retains substantially the same vapor pressure characteristics as Cu and shows a strong gas gettering effect, and achieves high voltage resistance and large capacity interruption. It is often used as a compatible contact.

Since this alloy uses highly active Cr, the contact material is manufactured (sintering step, etc.) while giving due consideration to the selection of the raw material powder, the mixing of impurities, and the management of the atmosphere. In addition, contact products are made with consideration given to processing from contact materials to contact pieces.

However, there have been cases where the occurrence of restriking triggers and lowers the breaking performance, and improvement thereof is desired.

[0008]

The contact surface of the CuCr contact shows a relatively smooth damage characteristic even after the current is interrupted, mainly due to the similarity of the vapor pressure characteristics at high temperatures. And stable electrical characteristics (stable contact resistance characteristics, excellent breaking characteristics, suppression of restriking, etc.). However, in recent years, it has been routinely applied to circuits where higher current interruption or higher voltage may be applied, resulting in the surface condition of a new contact processed and damage to the contact surface after current interruption. In some situations, re-ignition has been triggered. In other words, the surface condition during machining, or the contact surface that has been abnormally damaged or worn due to current interruption, may cause an abnormal increase in contact resistance or temperature when opening or closing the next steady current, This indicates a failure and contributes to the occurrence of restriking.

According to research, the re-ignition characteristics and cutoff characteristics of a CuCr alloy are based on the variation of the Cr content in the alloy, the particle size distribution of the Cr particles, the degree of segregation of the Cr particles, and the degree of vacancies existing in the alloy. And so on. It has also been found that the re-ignition characteristics and the cutoff characteristics of the CuCr alloy also depend on the change of the surface state of the Cu phase in the alloy, particularly before and after the cutoff.

[0010] However, in spite of the progress of the optimization, there is still variation in the above-mentioned adaptation situation in recent years, and a vacuum valve having both characteristics has been required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a contact material for a power vacuum circuit breaker which stabilizes a re-ignition characteristic of a CuCr alloy and has an excellent current interruption characteristic. Is to do.

[0012]

According to the present invention, there is provided a conductive component comprising a Cu phase composed of Cu or a Cu alloy containing Cu as a main component. And Cr having a particle diameter in the range of 0.1 to 150 μm.
After the sintering process or after the sintering / infiltration process, in the contact material of the electric vacuum circuit breaker made of a Cu-Cr alloy composed of a Cr-resistant component composed of Cr particles containing particles in a predetermined ratio or more. The hardness value (micro Vickers hardness value) of the Cr particles in the Cu-Cr alloy was Hs, and the C value in the Cu-Cr alloy was
[H] when the hardness value (micro Vickers hardness value) of Cr particles in the Cu—Cr alloy when heated to a temperature immediately below the melting temperature of the u phase and cooled to room temperature is Hr.
[s / Hr] ratio in the range of 1.0 to 1.6.

Here, the hardness value Hs of the Cr particles at the time of manufacturing the contact material (after the sintering process or after the sintering / infiltration process)
Is determined in such a way that the content of the raw material Cr, the heat treatment conditions selected during sintering and infiltration and the degree of residual strain during processing of the contact material are related to each other. For example, the Vickers hardness of Hs is 20.
The value near 0 is shown.

By the way, when this contact material is incorporated as a vacuum valve and actually operated, the contact surface is gradually changed (softened) when a steady current is opened or closed or an accident current is interrupted, and finally has a constant hardness value H. _B , during which the hardness value greatly decreases from the hardness value Hs near the initial Vickers hardness of 200. The hardness value H _B when the temperature finally becomes constant after actually operating the vacuum valve, and the hardness value of Cr particles when heated to a temperature T1 immediately below the melting temperature of the Cu phase and then cooled to room temperature. When compared with Hr, both (H _B ,
Hr) was found to show an approximate hardness value.

By the way to produce the vacuum valve for the measurement of H _B, actually economically like requiring a work interrupting and closing the current, because of the large adverse time burden, H _B and H
By using the above-mentioned property that r and r are approximately similar, Hr
To substitute H _B by, i.e. difficult H _B of the measurement
Instead of Hr, which is easy to measure, it is possible and advantageous to change the state of softening of the contact surface at the time of steady-state switching and fault current interruption.

The higher the hardness value Hs of the Cr particles at the time of manufacturing the contact material and the greater the difference from the hardness value Hr at the time of cooling to room temperature (ie, the larger the [Hs / Hr] ratio), the greater the re-pointing. It was also found that the frequency of arc generation tended to be large. [Hs /
If a contact with a [Hr] ratio exceeding 1.6 is selected, Cu
-The difference in hardness between the Cr particles and the Cu phase in the Cr alloy becomes large, and a stable machining surface state cannot be obtained due to the difference in hardness during the mechanical finishing of the contact. Not preferred.

According to a second aspect of the present invention, the temperature immediately below the melting temperature of the Cu phase in the Cu—Cr alloy is 1030 ° C.
The contact material of the vacuum circuit breaker for electric power according to claim 1, wherein the temperature is 1080 ° C.

Here, the hardness value of Cr when heat-treated at a temperature lower than the temperature T1 immediately below the melting temperature of the Cu phase (a temperature lower than 1030 ° C.), and the Cr value after current interruption / opening / closing
Hardness value of the H _B do not match. Therefore, when the hardness value of Cr when heat-treated at a temperature lower than T1 is used, [Hs
The relationship between the / Hr] ratio and the frequency of occurrence of restriking cannot be sufficiently coped with, and the product cannot be managed.

Further, according to the present invention, there is provided a conductive material comprising a Cu phase composed of Cu or a Cu alloy containing Cu as a main component, and a Cr component having a particle diameter in a range of 0.1 to 150 μm. After the sintering process or after the sintering / infiltration process, in the contact material of the electric vacuum circuit breaker made of a Cu-Cr alloy composed of a Cr-resistant component composed of Cr particles containing particles in a predetermined ratio or more. The hardness value (micro-Vickers hardness value) of the Cr particles in the Cu-Cr alloy is Hs, and the temperature is equal to or lower than the melting temperature of the Cu phase in the Cu-Cr alloy in a non-oxidizing atmosphere. [Hs / Hr] ratio when the hardness value (micro Vickers hardness value) of the Cr particles in the Cu-Cr alloy is Hr when heating at the above temperature and cooling it to room temperature is 1 Characterized by being adjusted to a range of 0.0 to 1.6. A contact material for a vacuum circuit breaker for power.

Here, it is preferable to select a non-oxidizing atmosphere as the manufacturing atmosphere for the Cu-Cr contact material, particularly for reducing the frequency of restriking.

Further, according to the present invention, a part of Cr is made up of 50% (% by weight) of Ti,
4. The contact material for a power vacuum circuit breaker according to claim 1, wherein the contact material is replaced by one selected from V, Nb, and Ta.

Here, part of Cr is replaced with Ti, V, Nb, T
Substitution by one of the above a increases the mechanical strength of the entire Cu-Cr contact material, and reduces the occurrence of restriking caused by falling off of Cr particles.
If the content exceeds 50% (% by weight), thermionic emission mainly due to these elements becomes active and the blocking characteristics are deteriorated.

Further, according to the present invention, the Cu phase contains Cr, T of not more than 20% (% by weight) based on the amount of Cu.
The contact material for a power vacuum circuit breaker according to any one of claims 1 to 4, further comprising one selected from i, V, B, Nb, and Ta.

Here, Cr, Ti, V,
The presence of B, Nb and Ta lowers the level of restriking and lowers the [Hs / Hr] ratio.

Further, the present invention according to claim 6 is characterized in that the amount of the Cu phase as a conductive component is 10 to 90% (% by weight), and the balance contains Cr as an arc resistant component. A contact material for a power vacuum circuit breaker according to any one of claims 1 to 5.

Here, when the amount of the Cu phase in the Cu—Cr alloy is less than 10%, the current interrupting characteristics are significantly reduced. Cu
When the amount of phase exceeds 90%, [Hs / H
[r] ratio, it is difficult to secure the ratio, and the frequency of restriking increases.

Further, according to the present invention, the amount of the Cu phase as a conductive component is 10 to 90% (% by weight),
At least one of Al and Si is used as an auxiliary component at a maximum of 1.
The contact material for a vacuum circuit breaker for electric power according to any one of claims 1 to 5, wherein 0% (% by weight) and Cr as an arc resistant component are contained in the remainder.

Here, the existence of the predetermined amounts of Al and Si is as follows.
It stabilizes the [Hs / Hr] ratio even lower, lowers the level of restriking, and further stabilizes the current cutoff characteristics. On the other hand, if the amount of at least one of Al and Si exceeds 1%, the surface of the contact piece is roughened due to a large energy treatment at the time of interruption, and the wear resistance and welding resistance are deteriorated, and the re-ignition characteristic is poor. Invites stabilization.

The present invention according to claim 8 further comprises 1% (% by weight) or less of one of Bi and Sb as the second auxiliary component. 12. A contact material for a vacuum circuit breaker for electric power according to any one of the above.

Here, if the presence of a predetermined amount of Bi (or Sb) in the Cu phase is 1% or less, the contact surface roughness after current interruption is stabilized, and the level of restriking is further reduced. 1
If the amount of Bi (or Sb) exceeds%, the frequency of occurrence of restriking increases, which is not preferable.

Further, according to the present invention, as the second auxiliary component, one of Te, Se and Pb of 5% (% by weight) or less is used.
The contact material for a power vacuum circuit breaker according to any one of claims 1 to 7, wherein the contact material comprises:

Here, a predetermined amount of Te, S in the Cu phase
The presence of e and Pb also stabilizes the contact surface roughness after current interruption and lowers the level of re-ignition.

Further, according to the present invention, the Cr particles have a mean particle diameter in the range of 0.1 to 150 μm.
r particles are at least 75% (by volume) of the total Cr particles
The contact material for a vacuum circuit breaker for electric power according to any one of claims 1 to 9, wherein the contact material is made of Cr powder occupying the following.

Here, the average particle size is 0.1 to 150 μm
When the Cr particles occupy at least 75% (vol%), stable re-ignition characteristics are exhibited. If the average particle diameter of the Cr particles is less than 0.1 μm, the Cr in the Cu—Cr alloy
The distribution of the particles cannot be sufficiently dispersed and there is an agglomerated portion, and the amount of gas in the Cu—Cr contact material cannot be reduced, and all of them increase the occurrence of restriking. 150 μm
When the surface roughness exceeds 1, the scratched scratches are left on the interface between the Cr particles and the Cu phase on the finished contact surface, making it difficult to obtain a smooth and uniform state, and a large variation in restriking occurs.

Further, according to the present invention, the present invention provides the
Alternatively, a conductive component composed of a Cu phase composed of a Cu alloy containing Cu as a main component and an arc-resistant component composed of Cr particles containing Cr particles having a particle diameter in a range of 0.1 to 150 μm or more in a predetermined ratio. The hardness value of the Cu phase in the Cu-Cr alloy after the sintering step or the sintering / infiltration step (micro- Vickers hardness value) is Hm, Cu-Cr
When heated to a temperature just below the melting temperature of the Cu phase in the alloy and cooled to room temperature, the Cu in the Cu-Cr alloy
A contact material for a vacuum circuit breaker for electric power, wherein the [Hm / Ho] ratio when the hardness value of the phase (micro Vickers hardness value) is Ho is in the range of 1.0 to 2.0. is there.

Here, the hardness value Hm of the Cu phase at the time of manufacturing the contact material (after the sintering step or after the sintering / infiltration step) is as follows:
The heat treatment conditions (for example, cooling rate) selected during sintering and infiltration and the degree of residual strain during contact processing are determined in relation to each other, and the Vickers hardness of Hm is a value near 100.

By the way, when this contact material is incorporated as a vacuum valve and actually operated, the contact surface gradually changes (softens) due to arc heat at the time of opening / closing of a steady current or at the time of interruption of an accident current, and finally, at a constant level. It shows the hardness value Hb, during which it changes (decreases) greatly from the hardness value Hm near the initial Vickers hardness of 100. The hardness value Hb when the vacuum valve was actually operated and finally became constant, and the hardness value Ho of the Cu phase when heated to a temperature T1 immediately below the melting temperature of the Cu phase and then cooled to room temperature, Compared to
It was found that both (Hb, Ho) showed almost similar hardness values.

However, the measurement of Hb is disadvantageous in that it is economical and time-consuming because the vacuum valve must be manufactured, and the current must be cut off and opened and closed. By using the property that Ho and Hb are almost similar values, Hb is substituted by Ho, that is, when Hb, which is difficult to measure, is replaced by Ho, which is easy to measure, when steady current switching and accident current interruption are performed. It is possible and advantageous to change the state of softening of the contact surface.

The hardness value of the Cu phase after sintering and infiltration of the contact material is large, and the difference from the hardness value of the Cu phase when cooled to room temperature (ie, the ratio of Hm / Ho) is Hm. It was also found that the larger the value, the greater the frequency of occurrence of restriking.
When a contact having a [Hm / Ho] ratio exceeding 2.0 is selected, the difference in hardness between the Cu phase and the Cr particles in the Cu-Cr alloy becomes large, and the difference in hardness during mechanical finishing of the contact causes A stable machined surface state cannot be obtained, which is not preferable for target low restrike.

Further, the present invention according to claim 12 is characterized in that Cu-
The temperature just below the melting temperature of the Cu phase in the Cr alloy is 103
The contact material for a power vacuum circuit breaker according to claim 11, wherein the contact temperature is 0C to 1080C.

Here, the hardness value of the Cu phase when heat-treated at a temperature lower than the melting temperature T1 of the Cu phase (a temperature lower than 1030 ° C.) and the C
The hardness value Hb of the u phase does not match. Therefore, when the hardness value of the Cu phase when heat-treated at a temperature lower than T1 is used,
The relationship between the [Hm / Ho] ratio and the frequency of occurrence of restriking cannot be sufficiently coped with, and quality control of products cannot be performed.

According to a thirteenth aspect of the present invention, there is provided an electroconductive device comprising a conductive component composed of Cu or a Cu phase composed of a Cu alloy containing Cu as a main component, and a Cr component having a particle diameter in a range of 0.1 to 150 μm. After the sintering process or after the sintering / infiltration process, in the contact material of the electric vacuum circuit breaker made of a Cu-Cr alloy composed of a Cr-resistant component composed of Cr particles containing particles in a predetermined ratio or more. The hardness value (micro-Vickers hardness value) of the Cu phase in the Cu-Cr alloy is Hm, and the temperature is equal to or lower than the melting temperature of the Cu phase in the Cu-Cr alloy in a non-oxidizing atmosphere. [Hm / Ho] ratio when the hardness value (micro-Vickers hardness value) of the Cu phase in the Cu-Cr alloy when heated at the above temperature and cooled to room temperature is 1 Power in the range of 0.0 to 2.0 A contact material for a vacuum circuit breaker.

Here, it is preferable to select a non-oxidizing atmosphere as the manufacturing atmosphere for the Cu—Cr contact material, particularly for reducing the frequency of restriking.

Further, according to the present invention, a part of Cr is reduced to a T content of 50% (% by weight) or less based on the amount of Cr.
14. The contact material for a power vacuum circuit breaker according to claim 11, wherein the contact material is replaced by one selected from i, V, Nb, and Ta.

Here, a part of Cr is changed to Ti, V, Nb, T
Substitution by one of the above a increases the mechanical strength of the entire Cu-Cr contact material, and reduces the occurrence of restriking caused by falling off of Cr particles.
If the content exceeds 50% (% by weight), thermionic emission mainly due to these elements becomes active and the blocking characteristics are deteriorated.

Further, according to the present invention, the Cu phase contains not more than 20% (% by weight) of Cr,
The contact material of a vacuum circuit breaker for electric power according to any one of claims 11 to 14, wherein the contact material contains one selected from Ti, B, V, Nb, and Ta.

Here, Cr, Ti, V,
The presence of B, Nb and Ta further lowers the level of restriking and stabilizes the [Hm / Ho] ratio.

The present invention according to claim 16 is characterized in that the amount of the Cu phase as the conductive component is 10 to 90% (% by weight), and the balance contains Cr as the arc resistant component. A contact material for a power vacuum circuit breaker according to any one of claims 11 to 15.

Here, if the amount of the Cu phase in the Cu—Cr alloy is less than 10%, the current interrupting characteristics are significantly reduced. Cu
When the amount of the phase exceeds 90%, the contact surface is worn away and the frequency of restriking increases.

Further, according to the present invention, the amount of the Cu phase as the conductive component is 10 to 90% (% by weight), and at least one of Al and Si is at most 1.0% as the first auxiliary component. The contact material for a vacuum circuit breaker for electric power according to any one of claims 11 to 15, wherein Cr (% by weight) and the remainder contain Cr as an arc-resistant component.

Here, the existence of the predetermined amounts of Al and Si is as follows.
It stabilizes the [Hm / Ho] ratio even lower, lowers the level of restriking, and further stabilizes the current cutoff characteristics. On the other hand, if the amount of at least one of Al and Si exceeds 1%, the surface of the contact piece is roughened due to a large energy treatment at the time of interruption, and the wear resistance and welding resistance are deteriorated, and the re-ignition characteristic is poor. Invites stabilization.

The present invention according to claim 18, further comprising 1% (% by weight) or less of one of Bi and Sb as the second auxiliary component. 12. A contact material for a vacuum circuit breaker for electric power according to any one of

Here, if the presence of a predetermined amount of Bi (or Sb) in the Cu phase is less than 1%, the contact surface roughness after current interruption is stabilized and the level of restriking is further reduced. 1
If the amount of Bi (or Sb) exceeds%, the frequency of occurrence of restriking increases, which is not preferable.

The present invention according to claim 19, further comprising 5% (% by weight) or less of one of Te, Se, and Pb as the second auxiliary component. 5. The contact material for a power vacuum circuit breaker according to any one of the above.

Here, a predetermined amount of Te, S in the Cu phase
The presence of e and Pb also stabilizes the contact back surface roughness after current interruption and lowers the level of re-ignition.

According to a twentieth aspect of the present invention, the Cr particles have a mean particle size of 0.1 to 150 μm.
r particles are at least 75% (by volume) of the total Cr particles
20. The contact material for a power vacuum circuit breaker according to any one of claims 11 to 19, wherein the contact material is made of Cr powder.

Here, the average particle diameter is 0.1 to 150 μm
When the Cr particles in the range occupy at least 7575% (% by volume), stable re-ignition characteristics are exhibited. When the average particle diameter of the Cr particles is less than 0.1 μm, the distribution of the Cr particles in the Cu—Cr alloy cannot be sufficiently dispersed, and there is an agglomerated portion, and the gas amount in the Cu—Cr contact material is low. In each case, the occurrence of restriking is increased. If the Cr particles exceed 150 μm, the width of the Cu phase becomes relatively large on the finished contact surface, and the Cu curl and C
Scratch-like flaws are left on the u-surface, making it difficult to obtain a smooth and uniform state, and showing large variations in the occurrence of restriking.

[0058]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail.

Regarding the material state of the Cu—Cr contact and the occurrence of restriking, the inventors have observed that the material properties before and after the interruption and the
The following findings were obtained regarding the relationship between the re-ignition variation and the occurrence. The Cu-Cr contact is generally finished by polishing, grinding or cutting means. However, even if the contents of Cu-Cr (manufacturing conditions, processing conditions, etc.) are fixed, variation in restriking still occurs. As a result of the observations by the inventors, it was found that Cr particles fell off on the contact surface and C
There were various things such as drop-off of the u-phase portion, flow (Cu covers the Cr particles) and peeling, chipping of Cr particle end portions, and scratches. One reason for this is that there was a correlation between the difference in workability on the contact surface, especially in the micro region, that is, the variation in the occurrence of restriking and the difference in hardness uniformity in the micro region. This tendency was observed between production lots of the contact material and also in the micro region of one contact. Further, it was recognized that the re-ignition frequency gradually became stable to a substantially constant value with the progress of the steady current switching operation and the fault current interruption operation. This situation is considered to indicate a phenomenon in which the contact surface gradually changes (softens) due to the arc heat and finally has a constant hardness value.

Therefore, the hardness value H _B of the Cr particles and the hardness value Hb of the Cu phase of the contact which became substantially constant after the accident current interruption operation was applied to the actual vacuum valve many times were measured. The hardness value Hr of the Cr particles in the same contact point and the hardness value Ho of the Cu phase when the temperature immediately below the melting temperature of the Cu phase portion of the contact point is selected, sufficiently heated at that temperature, and then cooled to room temperature. When compared with each other, it was found that both of them showed almost approximate values (H _B = Hr, Hb = Ho). Further, regarding the hardness value of the Cr particles, the hardness value (micro-Vickers hardness value) of the Cr particles in the Cu—Cr alloy after the sintering step or after the sintering / infiltration step is defined as Hs, When heated to a temperature just below the melting temperature of the Cu phase in and cooled to room temperature, Cu
Assuming that the hardness value (micro-Vickers hardness value) of the Cr particles in the Cr alloy is Hr, Hs is large, and the difference from Hr is large (that is, the [Hs / Hr] ratio is large), It was found that the frequency of occurrence of ignition tended to be large. [Hs / H
[r] ratio, a contact exceeding 1.6 is selected.
The difference in hardness between the Cr particles and the Cu phase in the Cr alloy becomes large, so that a favorable finished surface state cannot be obtained at the time of mechanical finishing of the contact point, which is not desirable for the target low re-ignition. On the other hand, when a contact having an [Hs / Hr] ratio of 1.6 or less, preferably 1.3 or less, is selected, the difference in hardness between the Cr particles and the Cu phase becomes small, and the mechanical finishing of the contact requires A favorable machined surface condition is obtained, a constant and stable surface condition is always obtained, and the stagnation and concentration of the arc are reduced.As a result, local abnormal evaporation of the contact surface is prevented and the surface roughness is reduced. It contributes to the improvement of the cutoff characteristics together with the benefit of low re-ignition.

As for the hardness value of the Cu phase, the hardness value (micro Vickers hardness value) of the Cu phase in the Cu—Cr alloy after the sintering step or immediately after the sintering / infiltration step is represented by Hm.
When heating to a temperature just below the melting temperature of the Cu phase in the Cu-Cr alloy and cooling this to room temperature, Cu-C
Assuming that the hardness value (micro Vickers hardness value) of the Cu phase in the r alloy is Ho, Hm is large and the difference from Ho is large (that is, the [Hm / Ho] ratio is large). It was recognized that the frequency of arc generation tended to be large. [Hm / Ho]
When a contact having a ratio exceeding 2.0 is selected, the difference in hardness between the Cr particles and the Cu phase becomes large, and a favorable machined surface state cannot be obtained during mechanical finishing of the contact. It is not preferable for ignition. In contrast, [H
When a contact having an [m / Ho] ratio of 2.0 or less, preferably 1.3 or less, is selected, the difference in hardness between the Cr particles and the Cu phase becomes small, and a favorable finished surface state is obtained during mechanical finishing of the contact. As a result, a constant and stable surface state is obtained at all times, and stagnation and concentration of the arc are reduced. As a result, local abnormal evaporation of the Cu phase portion on the contact surface is prevented, and surface roughness is reduced. This contributes to the improvement of the cutoff characteristics together with the benefit of restriking. When an external magnetic field (such as a vertical magnetic field) is applied to such a contact, the arc generated by the interruption is
It spreads uniformly on the contact surface and moves and diffuses, so that the current interruption characteristics can be improved. According to observation, when a current value equal to or more than a certain value is cut off, the arc tends to stagnate at one or more unpredictable points, but [Hs / Hr].
Contacts with a ratio of 1.6 or less tend to be lower and better than contacts with a ratio exceeding 1.6, and [Hm /
A contact having a [Ho] ratio of 2.0 or less tends to be lower and superior to a contact having a ratio exceeding 2.0. Eventually, a portion of the contact will melt abnormally, reaching the breaking limit. In addition, metal vapor generated by instantaneous explosive evaporation due to abnormal melting significantly impairs the insulation recovery of the vacuum circuit breaker in the process of opening, and further deteriorates the breaking limit. In addition, abnormal melting causes the formation of huge droplets, resulting in rough contact surfaces, lowering the withstand voltage characteristics, increasing the rate of restriking, and causing abnormal consumption of materials. Since it is impossible to predict at all where the arc contributing to these phenomena stagnates on the contact surface, a surface condition that allows the generated arc to move and diffuse without stagnation and means for promoting the movement and diffusion are provided. It is desirable to give to the contacts. In the present invention, as its desirable conditions,
[Hs / Hr] related to Cr particles in Cu-Cr alloy
Ratio, or [Hm /
Ho] ratio is important.

[1] Embodiment of Adjusting [Hs / Hr] Ratio As described above, to stabilize the contact characteristics of a CuCr alloy,
Variation of Cr content in alloy, Cr particle size, particle size distribution, C
Although it was recognized that the degree of segregation of r depends on the degree of vacancies present in the alloy, etc., in particular, in order to further stabilize the re-ignition characteristics, in addition to the above, the Cr particles in the CuCr alloy The behavior turned out to be extremely important. That is, it was found that it is necessary to pay attention to the change in the hardness of Cr in the alloy before and after shutting off the frequency of occurrence of restriking of the vacuum valve.

Therefore, first, an example and a comparative example in which a contact material is manufactured by adjusting the [Hs / Hr] ratio for Cr particles in a Cu—Cr alloy will be described. FIGS. 1 and 2 show the conditions for the trial production of the examples and comparative examples, and FIGS. 3 and 4 show the evaluation results of these examples and comparative examples.

(Evaluation of Breaking Characteristics) A flat contact having a surface roughness of 5 μm and a curvature radius of 1 having the same surface roughness
00R and a contact having a switching mechanism of a degree of vacuum of 10 ⁻³ Pa. Attached to the evacuated detachable vacuum cut-off experimental device below, with a load of 40 kg and 7.2 kV-
Injection / interruption is repeated 10 times at 20 kA to 31.5 kA. When the occurrence of welding or re-ignition is slight, it is judged as "Pass." Was "failed".

(Evaluation of Restriking Characteristics) The frequency of restriking when the circuit of 6 kV × 500 A was cut off 1,000 times was measured for six vacuum valves. Incidence rate (× 10
^-3 (%)) is 0.3 or less, S is evaluated, the range of 0.3-1 is evaluated A, the range of 1-3 is evaluated B, the range of 3-10 is evaluated C, and the range of 10-100 is evaluated. Evaluation Y, rating 100 or more Z
And

(Measurement of Hardness) The Cu phase portion and the Cr particles were individually subjected to a load of 10 to 25 using a micro Vickers hardness tester.
gr. Was measured.

(Adjustment of [Hs / Hr] ratio) The contact can be manufactured by either solid phase sintering or solid phase / infiltration.
Here, an example in which a Cr skeleton is manufactured and Cu is infiltrated into the voids will be described. Particle diameter 4
Cu powder in the range of 4 to 62 μm (95 to
99%). Particle diameter 0.1-150
Cu having a particle diameter similar to that of Cr powder in the range of μm (95-99% of all Cr powder) was prepared.

After the sintering step or the sintering / infiltration step,
When the hardness value (micro-Vickers hardness value) of the Cr particles in the Cu-Cr alloy is heated to Hs, a temperature just below the melting temperature of the Cu phase in the Cu-Cr alloy, and cooled to room temperature. [Hs] when the hardness value (micro-Vickers hardness value) of the Cr particles in the Cu—Cr alloy is Hr.
/ Hr] ratio was adjusted as follows. The pressing force applied to the Cr powder when molding the Cr powder is from 0 to
It is adjusted within a range of 8 tons / cm ² (the pressure is 0 when Cr is put in a container and sintered as it is). For example, when increasing the ratio, a high pressure value is selected. The sintering temperature when manufacturing the Cr skeleton is 800-
Adjust within the range of 1400 ° C. For example, when increasing the ratio, a lower temperature is selected from this temperature range. The temperature at which Cu is infiltrated into the Cr skeleton is 11
Adjust within the range of 00 to 1400 ° C. For example, when the ratio is increased, a lower infiltration temperature is selected. The cooling rate when cooling to room temperature after infiltration is 0.1
Adjust within the range of 〜１０10 ° C./min. For example, when increasing the same ratio, a small cooling rate is selected. A reheating treatment is added to the contact after sintering, sintering and infiltration, and the temperature is adjusted in the range of 500 to 1070 ° C. For example, when the ratio is increased, for example, a lower 65
Select a reheat temperature of 0-750 ° C. A re-pressurizing process is added to the contact after sintering, sintering and infiltration, and the re-pressing force is adjusted in a range of 4 to 10 ton / cm ² . For example, when the ratio is increased, a higher re-pressing force is selected so that the relative density before the re-pressing process is increased. When the [Hs / Hr] ratio is further finely adjusted, one selected from Cr, Ti, V, B, Nb, and Ta is appropriately added to the Cu phase. The ratio can be finely adjusted by adding an appropriate amount of one selected from Ti, V, Nb and Ta to Cr particles, or at least one of Al and Si as a first auxiliary component. .

By appropriately combining these components, a contact having an adjusted [Hs / Hr] ratio was obtained.

(Examples 1 to 3 and Comparative Examples 1 and 2) Using the Cu powder and the Cr powder prepared as described above, the powder having a predetermined [Hs / Hr] ratio by a solid-phase infiltration method is used. % Cu-
The remaining Cr alloy was manufactured (Examples 1 to 3, Comparative Examples 1 to 3).
2). In order to adjust the [Hs / Hr] ratio, at the time of manufacturing a contact, the above-mentioned or the above may be appropriately selected or combined.
Contacts having an [Hs / Hr] ratio of 1.0 to 1.6 (Examples 1 to 3) and 1.9 to 2.3 (Comparative Examples 1 and 2) were selected.

These contacts were mounted on a vacuum pulp for evaluation, and the re-ignition occurrence frequency (numerical value indicated by × 10 ⁻³ %) and the breaking characteristics were measured under the above-mentioned predetermined conditions. [Hs / Hr] ratio =
In the case of 1.0, when six valves were evaluated, the re-ignition occurrence frequency was evaluated (S to A), indicating good characteristics. As for the cutoff characteristic, the cutoff was successfully performed 10 times at 31.5 kA, and the cutoff characteristic was “pass”. According to the observation of the contact processing surface before the evaluation, it can be seen that almost uniformly polished and polished without distinction of the Cr particle portion and the Cu phase portion, showing an extremely stable contact surface condition, falling off of the Cr particles, polishing scratches. No surface roughness due to such factors has been observed. Microscopic observation of the outermost surface layer of the contact after the evaluation did not show any loss of Cr particles from the outermost layer region (Example 1).

When the [Hs / Hr] ratio was 1.3, the re-ignition frequency was evaluated (A to B), indicating good characteristics. As for the cutoff characteristic, the cutoff was successful 10 times at 24 kA, and the cutoff characteristic was “pass”. It can be seen that the surface is almost uniformly polished without distinction of the Cr particle portion and the Cu phase portion, and shows a very stable contact surface processing state, and no surface roughness due to falling off of the Cr particles, polishing scratches, etc. is observed ( Example 2).

Further, even when the [Hs / Hr] ratio was 1.6, the frequency of occurrence of restriking was evaluated (C) and good characteristics were exhibited. As for the cutoff characteristics, the cutoff was successfully performed 10 times at 20 kA, and the cutoff characteristics were “pass”. It can be seen that almost uniformly cut and polished without distinction between the Cr particle portion and the Cu phase portion.
There is no surface roughness due to dropping of r-particles, polishing scratches, etc., and the contact surface state is extremely stable (Example 3).

On the other hand, [Hs / Hr] ratio = 1.9
In the case of (1), the re-ignition occurrence frequency is evaluated (C to Y), and the re-ignition characteristics show a large deterioration and a large variation, which is not preferable. The shutoff characteristics are also "fail" indicating a large number of shutoff failures in the 20 kA shutoff test.
Traces of Cr particles falling off are observed on the processed surface before cutoff. There is local roughness on the contact surface after the interruption (Comparative Example 1).

When the [Hs / Hr] ratio is 2.3, the re-ignition occurrence frequency indicates the evaluation (Z), and the re-ignition characteristics are significantly deteriorated. The shutoff characteristics are also "fail" indicating a large number of shutoff failures in the 20 kA shutoff test.
A large variation is observed in the static withstand voltage value of the processed surface (Comparative Example 2).

As described above, the management of the [Hs / Hr] ratio is extremely important for achieving both the restriking characteristic and the cutoff characteristic, and the ratio is selected from the range of 1.0 to 1.6. Sometimes the goal is reached.

(Examples 4 to 6 and Comparative Examples 3 and 4) In the above example, the [Hs / Hr] ratio was varied when the amount of Cu in the Cu—Cr alloy was fixed at 75%. The effect of the present invention on restriking characteristics and cutoff characteristics was shown, but the present invention technology is not limited to the Cu amount of 75%, but the Cu amount is 90 to 10%.
The effects are also exerted in (Examples 4 to 6).

That is, when the [Hs / Hr] ratio was kept constant at 1.4, when the Cu content was 90%, the frequency of restriking was evaluated (C), indicating good characteristics. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 4).

Even when the Cu content was 50%, the frequency of restriking was evaluated (B to C), and good characteristics were exhibited. As for the blocking characteristics, the blocking was successfully performed 10 times at 24 kA, and the blocking characteristics were “pass” (Example 5).

Even when the Cu content was 10%, the re-ignition frequency was evaluated (A to B), and good characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 6).

On the other hand, when the Cu content is 95%, the re-ignition frequency indicates the evaluation (C to Y), and the re-ignition characteristics show a great deterioration and a large variation. Absent. However, the cutoff characteristic was 20 kA, and the cutoff characteristic was “pass”, but it is not preferable for achieving the object as a whole (Comparative Example 3).

On the other hand, when the Cu content is 5%, the re-ignition occurrence frequency is evaluated (Y to Z), and the re-ignition characteristics show a large deterioration and a large variation, which is not preferable.
The shutoff characteristics are also "fail" indicating a large number of shutoff failures in the 20 kA shutoff test. The breaking characteristics were remarkably reduced, and the temperature rise characteristics during the breaking test and the contact resistance characteristics after the breaking test were both significantly reduced (Comparative Example 4).

(Examples 7 to 12) In Examples 1 to 6, the Cu phase in the Cu-Cr alloy contained 0.01% C
Although the effect was shown about the example which used Cu containing the r component, the present invention technology showed that the component in the Cu phase was 0.01%.
The effect is exhibited without being limited to Cr.

That is, when the amount of Cu in the Cu—Cr alloy is fixed at 75%, the frequency of restriking occurs at a 75% Cu contact point containing 0.2% Cr component in the Cu phase. ,
Evaluations (S to A) were shown, and extremely good characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 31.5 kA, and the breaking characteristics were “pass” (Example 7).

The contact point in which 0.5% of Ti was contained in the Cu phase was evaluated for the occurrence of restriking (B to C) and exhibited good characteristics. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 8).

In the case of a contact containing 1.0% of V in the Cu phase, the re-ignition frequency was evaluated (B to C), and excellent characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 9).

At the contact point where 1.0% of B was contained in the Cu phase, the frequency of restriking was evaluated (B to C), and good characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 10).

In the case of the contact containing 10% of Nb in the Cu phase, the re-ignition frequency was evaluated (B), and good characteristics were exhibited. As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 10).

In the case of a contact containing 20% of Ta in the Cu phase, the frequency of occurrence of restriking was evaluated (B), indicating good characteristics. As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 12).

(Examples 13 to 16) When Cr containing Ti, V, Nb and Ta was used as a component in Cr particles in a Cu-Cr alloy, the re-ignition characteristics and the breaking characteristics were stable. Is useful for

That is, at the contact point where 1.0% of Ti is contained in the Cr particles, the re-ignition frequency is evaluated (S to A).
And exhibited extremely good characteristics. 3
The circuit was successfully cut off 10 times at 1.5 kA, and the cut-off characteristics were “pass” (Example 13).

In the contact point containing 2.0% of V in the Cr particles, the frequency of occurrence of restriking was evaluated (B), and good characteristics were exhibited. As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 14).

In the case of the contact containing 25% of Nb in the Cr particles, the frequency of occurrence of restriking was evaluated (A to B), and excellent characteristics were exhibited. As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 15).

In the case of the contact containing 50% Ta in the Cr particles, the frequency of occurrence of restriking was evaluated (B), and good characteristics were exhibited. As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 16).

(Examples 17-18, Comparative Example 5) In Examples 1-16, the Cr particles having an average particle diameter of 0.1-150 μm account for 95% or more (% by volume) of all Cr particles. However, in the present invention, the effect of Cr particles having an average particle diameter of 0.1 to 150 μm in all Cr particles is not limited to 95% or more.

That is, in the case of a contact using Cr in which the ratio of Cr having an average particle diameter of 0.1 to 150 μm in all Cr particles is 85% (vol%), the re-ignition frequency is evaluated (B). It showed good characteristics. 2
The blockage was successfully performed 10 times at 4 kA, and the cutoff characteristics were “pass” (Example 17).

Average particle diameter of all Cr particles 0.1
In the case of contacts using Cr having a Cr content of 75 μm (volume%) of 150 μm, the re-ignition occurrence frequency was evaluated (B to C).
And exhibited good characteristics. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 18).

On the other hand, in the case of a contact using Cr having a ratio of Cr having an average particle diameter of 0.1 to 150 μm in all the Cr particles and 50% (vol%), the re-ignition frequency is as follows:
The results (B to Z) show that the re-ignition characteristics show significant deterioration and large variations, which are not preferable. As for the shutoff characteristics, there were a success in shutting off at 20 kA and a failure in shutoff at 20 kA.

(Examples 19 to 23, Comparative Example 6) Cu-C
As a first auxiliary component in the Cr particles in the r alloy, 1.0
The use of Cr containing less than 0.1% of Al and Si is useful for stabilizing the re-ignition characteristics and cutoff characteristics.

That is, at the contact point where 1.0% of Al was contained in the Cr particles, the re-ignition frequency was evaluated (A to A).
B) and good characteristics were exhibited. 24k blocking characteristics
A was successfully cut off 10 times, and the cut-off characteristics were “pass” (Example 19).

At the contact point where 0.1% of Al was contained in the Cr particles, the re-ignition frequency was evaluated (S to A), indicating good characteristics. The breaking characteristic is 10 at 31.5 kA.
Times and the cutoff characteristics are "pass" (Example 2)
0).

In the case of the contact in which 0.01% of Al was contained in the Cr particles, the frequency of occurrence of restriking was evaluated (S to A), and extremely good characteristics were exhibited. 31.5k breaking characteristics
A was successfully cut off 10 times, and the cut-off characteristic was “pass” (Example 21).

In the contact point where 0.001% of Al was contained in the Cr particles, the re-ignition frequency was evaluated (S to A), and extremely good characteristics were exhibited. 31.5
The kA was successfully cut off 10 times, and the cutoff characteristics were “pass” (Example 22).

In the contacts containing 0.01% of Si in the Cr particles, the re-ignition occurrence frequency was evaluated (S to A), and extremely good characteristics were exhibited. 31.5k breaking characteristics
A was successfully cut off 10 times, and the cut-off characteristic was “pass” (Example 23).

On the other hand, 1.5% of A
In the contact containing l, the re-ignition occurrence frequency is evaluated (Y
To Z) are not preferred. 31.5kA breaking characteristics
In the shut-off test, there was a valve which re-ignited 8 times out of 10 times, and was "Fail" (Comparative Example 6).

(Examples 24-29, Comparative Examples 7-8) Second
When a Cu—Cr alloy containing 1.0% or less of Bi and Sb is used as an auxiliary component, it is useful for stabilizing the re-ignition characteristics and the cutoff characteristics. C containing 5.0% or less of Te, Se, and Pb as another second auxiliary component
Use of a u-Cr alloy is also useful for stabilizing restriking characteristics and cutoff characteristics.

That is, in the contact containing 0.1% Bi as the second auxiliary component in the Cu—Cr alloy, the re-ignition occurrence frequency was evaluated (B), and excellent characteristics were exhibited. . As for the breaking characteristics, the breaking was successful 10 times at 24 kA, and the breaking characteristics were “pass” (Example 24).

In the contact containing 1.0% Bi as the second auxiliary component in the Cu-Cr alloy, the re-ignition frequency was evaluated (B to C) and showed good characteristics. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 25).

In the contact containing 0.2% of Sb as the second auxiliary component in the Cu-Cr alloy, the re-ignition occurrence frequency was evaluated (B to C), and excellent characteristics were exhibited. .
As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 26).

In the case of the contact containing 2.5% Te as the second auxiliary component in the Cu-Cr alloy, the re-ignition frequency was evaluated (B to C) and exhibited good characteristics. .
As for the breaking characteristic, the breaking was successful 10 times at 20 kA, and the breaking characteristic was “pass” (Example 27).

In the case of the contact containing 5.0% Te as the second auxiliary component in the Cu-Cr alloy, the re-ignition occurrence frequency was evaluated (C), and excellent characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 28).

In the contact containing 2.5% of Se as the second auxiliary component in the Cu-Cr alloy, the frequency of restriking was evaluated (B to C), and good characteristics were exhibited. .
As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 29).

Also, the contacts containing 0.2% of Pb as the second auxiliary component exhibit the same re-ignition occurrence frequency and cutoff characteristics, and are "passed".

In the case of the contact containing 3.0% Bi as the second auxiliary component in the Cu-Cr alloy, the re-ignition occurrence frequency was evaluated (Y to Z), indicating a large re-ignition characteristic. It is not preferable because of serious deterioration. As for the cutoff characteristic, re-ignition frequently occurs at a cutoff of 20 kA or less, and the cutoff characteristic is “fail” (Comparative Example 7). After the cutoff test, the contact surface is markedly rough. The contact resistance also varied.

For the contact containing 8.0% of Te as the second auxiliary component in the Cu-Cr alloy, the re-ignition occurrence frequency is evaluated (Y to Z), and the re-ignition characteristic is shown by Daifuku. This is not preferable because significant deterioration is observed and large variations occur.
As for the cutoff characteristics, there were a success in shutting off at 20 kA and a failure in shutoff at 20 kA. After the cutoff test, the contact surface is markedly rough. The contact resistance also varied.

(Other Embodiments) Cu-Cr after the sintering step or after the sintering / infiltration step is removed in a non-oxidizing atmosphere.
The Cu-Cr alloy is heated at a temperature lower than the melting temperature of the Cu phase or higher than the melting temperature of the Cu phase, and is cooled to room temperature. After the process, the hardness value (micro Vickers hardness value) of the Cr particles in the Cu—Cr alloy is Hs, and the temperature is equal to or lower than the melting temperature of the Cu phase in the Cu—Cr alloy in a non-oxidizing atmosphere. The [Hs / Hr] ratio when the hardness value (micro Vickers hardness value) of the Cr particles in the Cu-Cr alloy when Hr is heated at a temperature equal to or higher than the melting temperature and cooled to room temperature is Hr. , 1.0 to 1.6.

As described above, by selecting a non-oxidizing atmosphere as the manufacturing atmosphere for the Cu-Cr contact material, it is possible to reduce the frequency of occurrence of restriking in particular.

[2] Example of Adjusting [Hm / Ho] Ratio As described above, the stabilization of the contact characteristics of a CuCr alloy depends on the state of the Cu phase in the alloy (surface roughness, degree of vacancies). ), The size of the Cu phase (grain size, degree of grain size distribution), etc., but in particular, for further stabilization of restrike characteristics, in addition to the above, the Cu-Cr alloy It has been found that the behavior of the Cu phase is extremely important. That is, the frequency of occurrence of restriking of the vacuum valve depends on the Cu in the alloy before and after shutoff.
It was found that it was necessary to pay attention to the change in hardness of the steel.

An example and a comparative example in which the [Hm / Ho] ratio for the Cu phase in the Cu—Cr alloy is adjusted to produce a contact material will be described. 5 and 6 show the conditions for trial production of the examples and comparative examples, and FIGS. 7 and 8 show the evaluation results of these examples and comparative examples.

(Evaluation of cut-off characteristics) In the case of adjusting the [Hm / Ho] ratio, the surface roughness was finished to 5 μm in the same manner as in the case of adjusting the [Hs / Hr] ratio. Flat contact, radius of curvature 100R with the same surface roughness
And a contact degree of 10 ^-3 Pa. Attached to the evacuated detachable vacuum cut-off experimental device below, load 40 kg, 7.2 kV-20 kA
Injection / interruption was repeated 10 times at ３31.5 kA, and when the occurrence of welding or restriking was light, it was regarded as “pass”. Injection / shutoff was repeated 10 times, and when re-ignition or welding frequently occurred, it was regarded as "fail".

(Evaluation of Restriking Characteristics) The frequency of restriking when the circuit of 6 kV × 500 A was cut off 1,000 times was measured for six vacuum valves. Incidence rate (× 10
^-3 (%)) is 0.3 or less, S is evaluated, 0.3 to 1 is evaluated A, 1 to 3 is evaluated B, 3 to 10 is evaluated C, and 10 to 100 is evaluated. Was evaluated as Y, and 100 or more was evaluated as Z.

(Measurement of Hardness) A Cu phase portion was subjected to a load of 10 to 25 gr using a micro Vickers hardness meter. Was measured.

(Adjustment of [Hm / Ho]) The contact can be manufactured by either the solid phase sintering method or the sintering / infiltration method. The hardness value (micro Vickers hardness value) of the Cu phase in the Cu—Cr alloy after the sintering step or the sintering / infiltration step is Hm,
When heated to a temperature just below the melting temperature of the Cu phase in the Cu-Cr alloy and cooled to room temperature, the hardness value (micro-Vickers hardness value) of the Cu phase in the Cu-Cr alloy is denoted by Ho. The contact having a predetermined [Hm / Ho] ratio at the time of
The adjustment was made as follows. (1) In the former method employing the solid phase sintering method, Cr powder having a particle diameter in the range of 0.1 to 150 μm (occupying 95 to 99% of the total Cr powder) is prepared and approximated to this. As Cu having a particle diameter, C in the range of 44 to 62 μm
u powder (95-99% of the total Cu powder) is prepared.
After mixing and molding a predetermined ratio of Cu and Cr, for example, 1
Solid phase sintering is performed at 030 ° C. to produce a Cu—Cr alloy. It is to be noted that the Cu content in the Cu—Cr alloy can be adopted in all ranges of alloys having a Cu content of 5 to 95%.
Applied for alloys in the range 0-95%, 5-45%.

A) The pressing force applied to the mixed powder at the time of molding the Cu-Cr mixed powder is in the range of 0 to 8 ton / cm ² (the pressing force is 0 when Cr is put in a container and sintered as it is). [Hm / Ho] ratio is adjusted to be small.

B) The cooling rate at the time of cooling to room temperature after solid-phase sintering is adjusted to a range of 0.1 to 10 ° C./min. For example, if the cooling rate is selected to be smaller, the hardness value Hm of the Cu phase becomes smaller, which is useful for reducing the [Hm / Ho] ratio.

C) A re-pressurizing treatment with a re-pressing force in the range of 4 to 10 ton / cm ² is added to the contact after the solid phase sintering,
[Hm / Ho] ratio is adjusted to be small.

D) When further finely adjusting the [Hm / Ho] ratio, Cr, Ti, V, B, Nb, T
The ratio can be finely adjusted by adding an appropriate amount of one selected from a or by adding an appropriate amount of at least one of Al and Si as the first auxiliary component. By appropriately combining A), B), C) and D), a contact having an adjusted [Hm / Ho] ratio was obtained. (2) In the latter production using the infiltration method, a Cr powder having a particle diameter in the range of 0.1 to 150 μm (occupying 95 to 99% of the total Cr powder) is prepared. A Cu lump for infiltration is prepared. After producing a Cr skeleton at, for example, 1200 ° C. using this Cr, Cu is infiltrated into the voids to form Cu-
Manufacture a Cr alloy. In addition, it applied to the alloy whose Cu content in a Cu-Cr alloy is 45-60%. The pressing force applied to the Cr powder when molding the Cr powder is from 0 to
It is adjusted within a range of 8 tons / cm ² (the pressure is 0 when Cr is put in a container and sintered as it is). For example, when increasing the ratio, a high pressure value is selected. The temperature at which Cu is infiltrated into the Cr skeleton is 11
Adjust within the range of 00 to 1400 ° C. The cooling rate when cooling to room temperature after infiltration is 0.1
Adjust within the range of -10 ° C / min. For example, if the cooling rate is selected to be smaller, the hardness Hm of the Cu phase becomes smaller and [H
[m / Ho] ratio. A reheat treatment is added to the contact after infiltration, and the temperature is increased in the range of 500 to 1070 ° C, substantially 650 to
Select the reheating temperature at 750 ° C., [Hm / Ho]
The ratio is adjusted to be small. For the contact point after infiltration, the re-pressing force is 4 to 10 tons / c
A re-pressurizing process in the range of m ² is added to adjust the [Hm / Ho] ratio to a small value. When the [Hm / Ho] ratio is further finely adjusted, one of Cr, Ti, V, B, Nb, and Ta is appropriately added to the Cu phase, or the first phase is added. Fine adjustment of the ratio is possible by adding at least one of Al and Si as an auxiliary component in an appropriate amount. By appropriately combining these, a contact having an adjusted [Hm / Ho] ratio was obtained.

(Examples 30 to 32, Comparative Examples 9 to 10) 75% having a predetermined [Hm / Ho] ratio by the solid phase sintering method using the Cu powder and the Cr powder prepared as described above. C
A u-remainder Cr alloy was produced (Examples 30 to 32, Comparative Examples 9 to 10).

In order to adjust the [Hm / Ho] ratio, 1.0 to 2.0 (Examples 30 to 3) can be obtained by appropriately selecting or combining the above A), B), C) and D) when manufacturing the contacts.
2) [Hm / H] of 2.6 to 3.0 (Comparative Examples 9 to 10)
o] A contact having a ratio was selected.

These contacts were mounted on an evaluation vacuum valve, and the re-ignition occurrence frequency (a numerical value indicated by × 10 ⁻³ %) and the cutoff characteristics were measured under the above-mentioned predetermined conditions. [Hm / Ho] ratio =
In the case of 1.0, when six valves were evaluated, the frequency of restriking was evaluated (S) and exhibited extremely good characteristics. 24. The kA was successfully cut off 10 times, and the cutoff characteristics were "pass". According to the observation of the contact processing surface before the evaluation, it can be seen that the Cu phase portion was completely uniformly cut and polished, showing an extremely stable contact surface state,
No surface roughness due to falling off of the Cu phase, polishing scratches or the like is observed. Microscopic observation of the outermost surface layer of the contact after the evaluation did not show that the Cu phase dropped out of the outermost layer region (Example 3).
0). Note that an alloy having an [Hm / Ho] ratio of less than 1.0 exhibits the same good performance in terms of characteristics.

When the [Hm / Ho] ratio was set to 1.3, the re-ignition frequency was evaluated (A to B), indicating good characteristics. The cutoff characteristic was “passed” because the cutoff was successful 10 times at 24 kA. It can be seen that the Cu phase portion is almost uniformly cut and polished, and shows an extremely stable processing state of the contact surface. No surface roughness due to falling off of the Cu phase, polishing scratches or the like is observed. Microscopic observation of the outermost surface layer of the contact after the evaluation did not show the Cu phase falling off from the outermost surface layer region (Example 31).

Further, even when the [Hm / Ho] ratio was set to 2.0, the frequency of restriking was evaluated (C), indicating good characteristics. The cutoff characteristics were also successfully cut off 10 times at 20 kA, and the cutoff characteristics were "pass". It can be seen that the Cu phase portion was almost uniformly cut and polished, and there was no surface roughness due to falling off of the Cu phase, polishing scratches, etc., and the contact surface state was extremely stable (Example 32).

On the other hand, [Hm / Ho] ratio = 2.6.
In the case of (1), the re-ignition occurrence frequency indicates the evaluation (Y to Z), and the re-ignition characteristics show a large deterioration and a large variation, which is not preferable. The shutoff characteristics are also "fail" indicating a large number of shutoff failures in the 20 kA shutoff test.
Traces of detachment of the Cu phase are observed on the processed surface before cutoff. There is local roughness on the contact surface after the interruption (Comparative Example 9).

Further, even when the [Hm / Ho] ratio is 3.0, the re-ignition occurrence frequency indicates the evaluation (Z), and the re-ignition characteristics are significantly deteriorated. The shutoff characteristics are also "fail" indicating a large number of shutoff failures in the 20 kA shutoff test.
A large variation is observed in the static withstand voltage value of the processed surface (Comparative Example 10).

As described above, the management of the [Hm / Ho] ratio is extremely important for achieving both the restriking characteristic and the cutoff characteristic, and the [Hm / Ho] ratio is selected in a range of 2.0 or less. When you reach your goal.

(Examples 33 to 35, Comparative Examples 11 to 12)
In the above embodiment, the amount of Cu in the Cu—Cr alloy was reduced to 75%
The effect of the [Hm / Ho] ratio on restriking characteristics and cutoff characteristics when the [Hm / Ho] ratio was varied when the ratio was constant was shown. %, The amount of Cu is 90 to 10% (Examples 33 to 3)
The effect is also exhibited in 5).

That is, [Hm / Ho] ratio = 1.2 to
When the Cu content was 90% when the Cu content was constant at 1.4, the re-ignition occurrence frequency was evaluated (B to C) and exhibited good characteristics. As for the blocking characteristics, the blocking was successfully performed 10 times at 24 kA, and the blocking characteristics were “pass” (Example 33). Microscopic observation of the outermost layer showed that there was no Cu phase falling off from the processed surface and no scratches were formed, and no Cu phase was dropped from the contact surface after the evaluation.

Even when the Cu content was 60%, the frequency of occurrence of restriking was evaluated (B) and good characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 34).

Even when the Cu content was 10%, the re-ignition frequency was evaluated (A to B), showing good characteristics. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 35). Microscopic observation of the outermost layer showed that there was no Cu phase falling off from the processed surface and no processing damage, and no Cu phase dropped out of the contact surface after the evaluation.

On the other hand, when the Cu content is 95%, the re-ignition frequency is evaluated (C to Y), and the re-ignition characteristics show a large deterioration and a large variation. Absent. However, the cutoff characteristics were 20 kA, and the cutoff characteristics were "pass". However, welding was observed in some parts, which was not preferable for achieving the objective (Comparative Example 11).

On the other hand, when the amount of Cu is 5%, the re-ignition frequency is evaluated (Y to Z), and the re-ignition characteristics show a large deterioration, and unfortunately show a large variation.
The shutoff characteristics are also "fail" indicating a large number of shutoff failures in the 20 kA shutoff test. The breaking characteristics are remarkably reduced, and the temperature rise characteristics during the breaking test and the stability of the contact resistance characteristics after the breaking test are poor (Comparative Example 12). Microscopic observation of the outermost layer showed remarkable processing flaws on the processed surface. The static withstand voltage value is lowered due to the processing flaw. In addition, a part of the Cu phase was dropped due to mechanical impact during processing. C from the contact surface after breaking evaluation
Dropout of the u phase was observed.

As described above, the technology of the present invention for controlling the [Hm / Ho] ratio of the Cu phase in the Cu—Cr alloy to a predetermined amount is effective when the Cu phase amount in the Cu—Cr alloy is 90 to 10%. It is effective.

(Examples 36 to 41) Examples 30 to 3
In No. 5, the component present in the Cu phase in the Cu—Cr alloy was not noted, but the present invention technology for managing the [Hm / Ho] ratio for the Cu phase in the Cu—Cr alloy uses Cu Cu. A predetermined amount of Cr, Ti, B, V, Nb,
Cu (Cr, Ti, B,
V, Nb, or Ta) The re-ignition characteristics and the cutoff characteristics are stabilized even for the -Cr alloy.

That is, when the amount of Cu in the Cu—Cr alloy is fixed at 75%, the frequency of restriking occurs at a 75% Cu contact point containing 0.1% Cr component in the Cu phase. ,
Evaluation (A) was shown and good characteristics were exhibited. The blocking characteristics are also
24. The kA was successfully cut off 10 times, and the cut-off characteristic was “pass” (Example 36).

In the case of the contact containing 0.3% of Ti in the Cu phase, the re-ignition occurrence frequency was evaluated (A to B), and excellent characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 37).

In the case of the contacts containing 0.5% of B in the Cu phase, the re-ignition frequency was evaluated (A to B), and good characteristics were exhibited. As for the cutoff characteristic, the cutoff was successful 10 times at 24 kA, and the cutoff characteristic was “pass” (Example 38).

In the case of the contacts containing 1.5% of V in the Cu phase, the re-ignition occurrence frequency was evaluated (B), and excellent characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 39).

For the contacts containing 10% Nb in the Cu phase, the re-ignition occurrence frequency was evaluated (B to C), and good characteristics were exhibited. As for the blocking characteristics, the blocking was successfully performed 10 times at 24 kA, and the blocking characteristics were “pass” (Example 40).

In the case of a contact containing 20% of Ta in the Cu phase, the frequency of occurrence of restriking was evaluated (B to C), and excellent characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 24 kA, and the breaking characteristics were “pass” (Example 41).

As shown in Examples 36 to 41, the addition of a predetermined amount of Cr, Ti, B, V, Nb, and Ta to the Cu phase suppresses the falling off of the Cu phase and stabilizes the re-ignition characteristics. Contributes to

As described above, the technique of the present invention for controlling the [Hm / Ho] ratio with respect to the Cu phase in the Cu—Cr alloy to a predetermined amount is based on the fact that a predetermined amount of Cr, Ti, B, V, Nb, T
Cu-Cr employing Cu containing any one of a
It is also effective for alloys.

(Examples 42 to 45) In the technique of the present invention for controlling the [Hm / Ho] ratio for the Cu phase in a Cu-Cr alloy, a predetermined amount of Ti, V, Nb, Ta was contained in Cr particles. Cu-Cr (Ti, V, Nb, Ta) using Cr
Any one of the above) also stabilizes the restriking characteristic and the breaking characteristic.

That is, the [Hm / Ho] ratio is set to 1.2 to
After keeping constant at 1.4, 0.5% Ti
In the contact containing, the re-ignition occurrence frequency is evaluated (A to
B) and good characteristics were exhibited. 24.
The kA was successfully cut off 10 times and the cut-off characteristic was “pass” (Example 42).

At the contact point where 2.0% V was contained in the Cr particles, the re-ignition frequency was evaluated (B), indicating good characteristics. As for the breaking characteristic, the breaking was successful 10 times at 20 kA, and the breaking characteristic was “pass” (Example 43).

In the case of the contact in which Cr particles contained 25% of Nb, the re-ignition frequency was evaluated (B), and excellent characteristics were exhibited. As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 44).

At the contact point where 50% of Ta was contained in the Cr particles, the re-ignition frequency was evaluated (B), indicating good characteristics. As for the blocking characteristics, the blocking was successfully performed 10 times at 24 kA, and the blocking characteristics were “pass” (Example 45).

A predetermined amount of Ti, V, Nb,
The effect of the presence of Ta acts on the interface between the Cu phase and the Cr particles to improve the wear resistance and the withstand voltage characteristics of the alloy as a whole.
[m / Ho] ratio is controlled to a predetermined amount, and the synergistic effect with the technology of the present invention contributes to stabilization of the contact characteristics by reducing the variation width of the re-ignition occurrence frequency.

As described above, the technique of the present invention for controlling the [Hm / Ho] ratio for the Cu phase in the Cu—Cr alloy to a predetermined amount is based on the Cr containing Cr, which contains a predetermined amount of Ti, V, Nb, and Ta. Cu-Cr (Ti, V, Nb, Ta)
One of them) is also effectively exerted on alloys.

(Examples 46 to 47, Comparative Example 13) In Examples 30 to 45, Cr particles having an average particle diameter of 0.1 to 150 μm accounted for 95% (% by volume) of all Cr particles.
Although the effect was shown for the example occupying the above (0.95 to 0.99), in the present invention technology, 95% of the Cr particles having an average particle diameter of 0.1 to 150 μm occupy 95% ( The present invention can be applied without being limited to the case of a Cu—Cr alloy having a volume percentage of at least.

That is, in a Cu-Cr contact using Cr having an average particle diameter of 0.1 to 150 μm in all the Cr particles and a ratio of Cr of 85% (vol%), the re-ignition occurrence frequency is as follows: Evaluation (B) was shown and good characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 46).

The average particle diameter of all Cr particles is
For a contact using Cr having a Cr content of 75% (volume%) of 0.1 to 150 μm, the re-ignition frequency was evaluated (B
To C) and exhibited good characteristics. 20
The kA was successfully cut off 10 times, and the cut-off characteristic was “pass” (Example 47).

On the other hand, the proportion of Cr having an average particle diameter of 0.1 to 150 μm in all Cr particles was 50%.
In the case of contacts using (volume%) Cr, the re-ignition occurrence frequency is evaluated (C to Z), and the re-ignition characteristics show a large deterioration and a large variation, which is not preferable. As for the shutoff characteristics, only one of the evaluated valves succeeded in shutting down 20 kA, but all the other five valves did not.
The kA could not be cut off frequently, the dispersion was large, and the cutoff characteristics were "fail" (Comparative Example 13).

As described above, the technique of the present invention for controlling the [Hm / Ho] ratio for the Cu phase in the Cu—Cr alloy to a predetermined amount is such that the ratio of the average particle diameter in all Cr particles is 75%.
(% By volume) is effectively exhibited in a Cu-Cr alloy employing Cr particles of not less than (volume%).

(Examples 48 to 52, Comparative Example 14) Cu-
As the first auxiliary component in the Cr particles in the Cr alloy,
The use of Cr containing 0% or less of Al and Si is useful for stabilizing the re-ignition characteristics and the cutoff characteristics.

That is, at the contact point where 1.0% of Al was contained in the Cr particles, the frequency of restriking was evaluated (C), and excellent characteristics were exhibited. The breaking characteristics are also 20kA.
The interruption was successful 0 times, and the interruption characteristics were “pass” (Example 4).
8).

In the case of the contact containing 0.1% of Al in the Cr particles, the frequency of occurrence of restriking was evaluated (B) and good characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 49).

At the contact point where 0.01% of Al was contained in the Cr particles, the frequency of occurrence of restriking was evaluated (S to A), and extremely good characteristics were exhibited. 31.5k breaking characteristics
A was successfully cut off 10 times, and the cut-off characteristics were "pass" (Example 50).

In the case of the contact in which 0.001% of Al was contained in the Cr particles, the re-ignition occurrence frequency was evaluated (A), and extremely good characteristics were exhibited. The breaking characteristics are also 20kA.
The blockage was successfully performed 0 times and the cutoff characteristics were “pass” (Example 5).
1).

At the contact point where 0.01% of Si was contained in the Cr particles, the re-ignition frequency was evaluated (S to A), and extremely good characteristics were exhibited. 31.5k breaking characteristics
A was successfully cut off ten times, and the cut-off characteristics were "pass" (Example 52).

In each case, the contact surfaces were stable without the Cu phase falling off or peeling off.

On the other hand, when Cr containing 1.5% of Al was used as the first auxiliary component in the Cr particles in the Cu—Cr alloy, the frequency of occurrence of restriking was evaluated as follows. (Z), which is not preferable because re-ignition characteristics are significantly deteriorated. The blocking characteristics are 8 times during 10 times 24 kA blocking, 2 times.
The occurrence of re-ignition twice was recorded during the 0 kA interruption, and interruption was frequently caused, and the interruption characteristic was “fail” (Comparative Example 14). A drop of the Cu phase has already been seen on the contact surface immediately after processing, and this has triggered the first re-ignition.

As described above, the technology of the present invention for controlling the [Hm / Ho] ratio for the Cu phase in the Cu—Cr alloy to a predetermined amount is based on the following. Cu-Cr using Cr particles containing Si and Si
It is also applicable to alloys.

(Examples 53 to 58, Comparative Examples 15 to 16)
When a Cu-Cr alloy containing 1.0% or less of Bi and Sb is used as the second auxiliary component, it is useful for stabilizing the re-pointing property and the blocking property. Also, when a Cu—Cr alloy containing 5.0% or less of Te, Se, and Pb is used as another second auxiliary component, the re-ignition characteristics,
It is useful for stabilizing the blocking characteristics.

That is, in the contact containing 0.1% Bi as the second auxiliary component in the Cu—Cr alloy, the re-ignition occurrence frequency was evaluated (B), and excellent characteristics were exhibited. . As for the breaking characteristics, the blocking was successfully performed 10 times at 24 kA, and the breaking characteristics were “pass” (Example 53).

For the contact containing 1.0% Bi as the second auxiliary component in the Cu-Cr alloy, the frequency of restriking was evaluated (B to C), and excellent characteristics were exhibited. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 54).

In the contact containing 0.2% of Sb as the second auxiliary component in the Cu-Cr alloy, the re-ignition frequency was evaluated (B to C) and exhibited good characteristics. .
As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 55).

For the contact containing 2.5% of Te as the second auxiliary component in the Cu-Cr alloy, the frequency of restriking was evaluated (B to C), and good characteristics were exhibited. .
As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 56).

In the case of the contact containing 5.0% Te as the second auxiliary component in the Cu-Cr alloy, the frequency of occurrence of restriking was evaluated (C) and good characteristics were exhibited. As for the cutoff characteristic, the cutoff was successfully performed 10 times at 20 kA, and the cutoff characteristic was “pass” (Example 57).

In the case of the contact containing 2.5% Se as the second auxiliary component in the Cu-Cr alloy, the re-ignition frequency was evaluated (C) and showed good characteristics. As for the breaking characteristics, the breaking was successful 10 times at 20 kA, and the breaking characteristics were “pass” (Example 58).

Further, even if the contact contains 0.2% of Pb as the second auxiliary component in the Cu-Cr alloy, the same re-ignition occurrence frequency and cutoff characteristics are exhibited, and the result is "pass".

In each case, a stable contact surface was obtained without dropping or peeling of the Cu phase.

On the other hand, at the contact containing 3.0% Bi as the second auxiliary component in the Cu—Cr alloy, the frequency of occurrence of restriking is evaluated (Y to Z), and Significant deterioration is observed in the ignition characteristics, which is not preferable. 2
Re-ignition frequently occurs at a cut-off of 0 kA or less, and the cut-off characteristic is “fail” (Comparative Example 15). After the cutoff test, the contact surface is markedly rough. The contact resistance also varied.

At the contact containing 8.0% of Te as the second auxiliary component in the Cu-Cr alloy, the frequency of occurrence of restriking is evaluated (Z), indicating a significant deterioration in restriking characteristics. Is not preferred. As for the cutoff characteristics, 20 kA cutoff was successful and 20 kA cutoff failure occurred frequently, and the cutoff characteristics were “fail”.
(Comparative Example 16). After the cutoff test, the contact surface is markedly rough. The contact resistance also varied.

As described above, the technology of the present invention for controlling the [Hm / Ho] ratio for the Cu phase in the Cu—Cr alloy to a predetermined amount is a method for controlling the Bi content of 1.0% or less as the second auxiliary component in the Cr particles. , Sb-containing Cu-Cr alloy, or other second auxiliary component of less than 5.0% of Te, Se, Pb
Can also be applied to Cu-Cr alloys containing.

(Other Embodiments) Cu—Cr after the sintering step or after the sintering / infiltration step is subjected to a non-oxidizing atmosphere,
The Cu-Cr alloy is heated at a temperature lower than the melting temperature of the Cu phase or higher than the melting temperature of the Cu phase, and is cooled to room temperature. After the process, the hardness value (micro Vickers hardness value) of the Cu phase in the Cu—Cr alloy is Hm, and the temperature is equal to or lower than the melting temperature of the Cu phase in the Cu—Cr alloy in a non-oxidizing atmosphere. The [Hm / Ho] ratio when the hardness value (micro Vickers hardness value) of the Cu phase in the Cu—Cr alloy when the material is heated at a temperature equal to or higher than the melting temperature and cooled to room temperature is Ho. , 1.0 to 2.0.

As described above, by selecting a non-oxidizing atmosphere as the manufacturing atmosphere for the Cu-Cr contact material, it is possible to particularly reduce the frequency of restriking.

[0187]

As described above, according to the present invention,
Since the re-ignition characteristics of the CuCr alloy can be stabilized to provide a contact material for a power vacuum circuit breaker having excellent current interruption characteristics, its industrial value is great.

[Brief description of the drawings]

FIG. 1 is a table showing evaluation conditions of Examples 1 to 16 and Comparative Examples 1 to 4 of contact materials for a power vacuum circuit breaker according to the present invention.

FIG. 2 is a table showing evaluation conditions of Examples 17 to 29 and Comparative Examples 5 to 8 of the contact material of the power vacuum circuit breaker according to the present invention.

FIG. 3 is a table showing the evaluation results of Examples 1 to 16 and Comparative Examples 1 to 4 of the contact material of the electric vacuum circuit breaker according to the present invention.

FIG. 4 is a table showing evaluation results of Examples 17 to 29 and Comparative Examples 5 to 8 of the contact material of the electric vacuum circuit breaker according to the present invention.

FIG. 5 is a table showing the evaluation conditions of Examples 30 to 45 and Comparative Examples 9 to 12 of the contact material of the power vacuum circuit breaker according to the present invention.

FIG. 6 is a table showing the evaluation conditions of Examples 46 to 58 and Comparative Examples 13 to 16 of the contact material of the power vacuum circuit breaker according to the present invention.

FIG. 7 is a table showing evaluation results of Examples 30 to 45 and Comparative Examples 9 to 12 of the contact material of the vacuum circuit breaker for electric power according to the present invention.

FIG. 8 is a table showing evaluation results of Examples 46 to 58 and Comparative Examples 13 to 16 of the contact material of the power vacuum circuit breaker according to the present invention.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C22F 1/08 C22F 1/08 B 1/11 1/11 H01H 1/02 H01H 1/02 C 11/04 11/04 D // B22F 7/00 B22F 7/00 A C22F 1/00 627 C22F 1/00 627 628 628 661 661A 687 687 691 691B H01B 1/02 H01B 1/02 A (72) Inventor Takashi Kusano Tokyo 1 Toshiba-cho, Fuchu-shi, Toshiba Fuchu Plant (72) Inventor Atsushi Yamamoto 1 Toshiba-cho, Fuchu-shi, Tokyo Inside Fuchu Plant, Toshiba F-term (reference) 4K018 BB04 FA36 JA10 KA34 5G023 AA05 BA11 CA33 CA35 CA50 5G026 BA01 BB02 BB14 BB16 BB17 BB18 BB22 BC04 BC09 5G050 AA02 AA04 AA12 AA13 AA27 AA33 AA40 AA42 AA43 AA46 AA47 AA48 AA50 BA01 CA01 D A03 EA02 5G301 AA07 AA08 AD04 AE02

Claims (20)

[Claims] 1. A conductive component comprising a Cu phase composed of Cu or a Cu alloy containing Cu as a main component, and a conductive material having a particle diameter of 0.1%.
Cu-C composed of a Cr particle containing Cr particles in a range of .about.150 .mu.m or more and having a predetermined ratio or more.
In the contact material of the power vacuum circuit breaker made of r alloy,
After the sintering step or the sintering / infiltration step, the Cu-C
Heating the hardness value (micro Vickers hardness value) of the Cr particles in the r alloy to Hs, a temperature just below the melting temperature of the Cu phase in the Cu-Cr alloy, and cooling the same to room temperature, [Hs / Hr] when the hardness value (micro Vickers hardness value) of Cr particles in the Cu-Cr alloy is Hr
A contact material for an electric vacuum circuit breaker, wherein a ratio is in a range of 1.0 to 1.6. 2. The contact material for a vacuum circuit breaker for electric power according to claim 1, wherein the temperature immediately below the melting temperature of the Cu phase in the Cu—Cr alloy is 1030 ° C. to 1080 ° C. 3. A conductive component comprising a Cu phase composed of Cu or a Cu alloy containing Cu as a main component, and a conductive material having a particle diameter of 0.1%.
Cu-C composed of a Cr particle containing Cr particles in a range of .about.150 .mu.m or more and having a predetermined ratio or more.
In the contact material of the power vacuum circuit breaker made of r alloy,
After the sintering step or the sintering / infiltration step, the Cu-C
The hardness value (micro Vickers hardness value) of the Cr particles in the r alloy is Hs, and the temperature is equal to or lower than the melting temperature of the Cu phase or equal to or higher than the melting temperature of the Cu phase in the Cu—Cr alloy in a non-oxidizing atmosphere. [Hs / Hr] when the hardness value (micro Vickers hardness value) of the Cr particles in the Cu—Cr alloy when the material is cooled to room temperature is Hr.
A contact material for a power vacuum circuit breaker, wherein a ratio is adjusted in a range of 1.0 to 1.6. 4. A method according to claim 1, wherein a part of said Cr is 50% based on the amount of Cr.
(Weight%) 1 selected from the following Ti, V, Nb, Ta
4. The contact material for a power vacuum circuit breaker according to claim 1, wherein the contact material is replaced by one. 5. The Cu phase contains 20% by weight of Cu.
5. The vacuum circuit breaker for electric power according to claim 1, further comprising one selected from the group consisting of Cr, Ti, V, B, Nb, and Ta. Contact material. 6. The amount of Cu phase as a conductive component is 10 to 9
The contact material for a vacuum circuit breaker for electric power according to any one of claims 1 to 5, wherein 0% (% by weight) and the balance contain Cr as an arc resistant component. 7. The amount of the Cu phase as a conductive component is 10 to 9
4. The method according to claim 1, wherein the first auxiliary component contains at least one of Al and Si at a maximum of 1.0% (% by weight), and the remainder contains Cr as an arc resistant component. Item 6. A contact material for a power vacuum circuit breaker according to any one of Items 5. 8. The method according to claim 1, wherein the second auxiliary component contains 1% (% by weight) or less of one of Bi and Sb.
A contact material for a power vacuum circuit breaker according to claim 7. 9. The power vacuum according to claim 1, wherein the second auxiliary component contains one of Te, Se, and Pb of 5% (% by weight) or less. Contact material for circuit breakers. 10. The Cr particles have an average particle size of 0.1 to 0.1.
The power vacuum circuit breaker according to any one of claims 1 to 9, wherein the Cr particles in the range of 150 µm comprise Cr powder occupying at least 75% (by volume) of the entire Cr particles. Contact material. 11. A conductive component consisting of Cu or a Cu phase composed of a Cu alloy containing Cu as a main component, and a particle size of 0.1.
Cu-consisting of a Cr-resistant component composed of Cr particles containing Cr particles in a range of 1 to 150 μm or more in a predetermined ratio or more.
In the contact material of a vacuum circuit breaker for electric power made of a Cr alloy, the Cu after the sintering process or after the sintering / infiltration process is used.
-Heating the hardness value (micro Vickers hardness value) of the Cu phase in the Cr alloy to Hm, a temperature just below the melting temperature of the Cu phase in the Cu-Cr alloy, and cooling this to room temperature; [Hm / Ho] when the hardness value (micro Vickers hardness value) of the Cu phase in the Cu-Cr alloy is Ho.
A contact material for a vacuum circuit breaker for electric power, wherein the ratio is in the range of 1.0 to 2.0. 12. The contact material for a vacuum circuit breaker for electric power according to claim 11, wherein the temperature immediately below the melting temperature of the Cu phase in the Cu—Cr alloy is 1030 ° C. to 1080 ° C. 13. A conductive component consisting of Cu or a Cu phase composed of a Cu alloy containing Cu as a main component, and a particle size of 0.1.
Cu-consisting of a Cr-resistant component composed of Cr particles containing Cr particles in a range of 1 to 150 μm or more in a predetermined ratio or more.
In the contact material of a vacuum circuit breaker for electric power made of a Cr alloy, the Cu after the sintering process or after the sintering / infiltration process is used.
-The hardness value (micro Vickers hardness value) of the Cu phase in the Cr alloy is Hm, and in a non-oxidizing atmosphere, the temperature is equal to or lower than the melting temperature of the Cu phase in the Cu-Cr alloy or equal to or higher than the melting temperature of the Cu phase. [Hm / Ho] ratio when the hardness value (micro-Vickers hardness value) of the Cu phase in the Cu-Cr alloy when heated at a temperature and cooled to room temperature is set to 1. A contact material for a vacuum circuit breaker for electric power, wherein the contact material has a range of 0 to 2.0. 14. The method according to claim 14, wherein a part of said Cr is
The contact material for a vacuum circuit breaker for electric power according to any one of claims 11 to 13, wherein the material is replaced by one selected from Ti, V, Nb, and Ta of 0% (% by weight) or less. . 15. The Cu phase has a content of 20 to the Cu content.
% (% By weight) or less of one selected from the group consisting of Cr, Ti, B, V, Nb and Ta.
A contact material for a power vacuum circuit breaker according to claim 14. 16. The amount of the Cu phase as a conductive component is set to 10 to 10.
The contact material for a vacuum circuit breaker for electric power according to any one of claims 11 to 15, wherein 90% (% by weight) and Cr as an arc resistant component are contained in the balance. 17. The amount of the Cu phase as a conductive component is adjusted to 10 to 10.
12. The method according to claim 11, wherein the first auxiliary component contains at least one of Al and Si at a maximum of 1.0% (% by weight), and the remainder contains Cr as an arc resistant component.
A contact material for a power vacuum circuit breaker according to claim 15. 18. The vacuum circuit breaker for electric power according to claim 11, wherein one of Bi and Sb of 1% (% by weight) or less is contained as the second auxiliary component. Contact material. 19. The power vacuum according to claim 11, wherein the second auxiliary component contains one of Te, Se, and Pb of 5% (% by weight) or less. Contact material for circuit breakers. 20. The Cr particles have an average particle size of 0.1 to 0.1.
The power vacuum circuit breaker according to any one of claims 11 to 19, wherein the Cr particles in the range of 150 µm comprise Cr powder occupying at least 75% (by volume) of the entire Cr particles. Contact material.