JPH10241513A - Vacuum bulb - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vacuum bulb which can retain air-tightness for a long duration and exhibit vacuum circuit breaking characteristic. SOLUTION: As a solder to be used for joining of a sealing plate to seal the open side of an insulating container to the insulating container, a solder produced by previously uniting a Cu-Ti alloy containing Ti at 0.05-5% Ti/(Cu+ Ti) ratio with Ag or a Ag alloy containing Ag as a main component is used, so that the wettability of the sealing plate and the insulating container can be improved and the reliability of the joining part can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vacuum valve,
In particular, the present invention relates to a vacuum valve having an improved brazing material for sealing.

[0002]

2. Description of the Related Art An insulating container of a vacuum valve must maintain hermeticity for a long period of time in order to maintain vacuum shut-off conditions. BACKGROUND ART Conventionally, as a method for joining an insulating container of a vacuum valve and a sealing metal on both sides, first, a powder mainly containing molybdenum (Mo) or tungsten (W) is applied to an end surface of the insulating container, 1,400 for example in a reducing atmosphere
There is a method in which a metallized layer (for example, a coating of MoMn) is formed in advance by heating to 1,1,700 ° C., and bonding is performed with silver brazing via the metallized layer. A feature of this method is that a brazing filler metal of a general 72% AgCu alloy can be used.

[0003] Second, Ti,
There is a method in which an active metal such as Zr and a transition metal such as Ni and Cu are arranged, and these alloys are metallized at a predetermined temperature and joined to a sealing metal fitting (JP-A-56-163093).

A feature of this method is that a strong bonding force can be easily obtained. Thirdly, there is a method in which a brazing alloy containing an active metal (for example, an AgCuTi alloy) is disposed between the end face of the insulating container and the sealing metal and joined, and the feature of this method is that the process is simple and simple. That is what.

[0005]

Among them, the first method requires a high-temperature treatment in the step of forming the metallized layer, has many steps, and is economically inferior. Also, a slight difference in the processing conditions lowers and fluctuates the bonding strength.

[0006] Among them, the variation greatly affects the reliability of the airtightness, that is, the quality of the vacuum valve (cutoff performance including restriking). Further, in the second method, since a binder and an organic solvent are used, equipment for treating these waste liquids is required.

[0007] When the insulating container and the sealing metal are sufficiently overlapped with each other, they are satisfactorily joined with silver brazing. However, if there is a small gap or if there is a part which does not sufficiently overlap, the metallizing is sufficiently performed. May not be.

Therefore, it is necessary to take measures for bringing the parts into close contact with each other, and the pressurized parts for that purpose occupy the space in the furnace, and the productivity is poor. In particular, if an active metal such as Ti is not uniformly arranged on the end surface of the insulating container, the bonding force and the airtightness vary, and the cutoff characteristics deteriorate.

In Japanese Patent Application Laid-Open No. 63-49758, active metal Ti or Zr powder is used in order to make the pressure uniform.
An example in which this powder is applied to the end surface of an insulating container is shown.

[0010] By powdering the active metal, Ti or Z
r is uniformly distributed on the end face and closely adhered to obtain a vacuum valve having bonding strength and airtightness.

However, an insulating container coated with a binder such as polyvinyl alcohol, ethyl cellulose, etc.
Alternatively, in the step of applying the Zr powder, an organic solvent such as ethanol or tetralin turns the active metal powder into a paste state, so that a treatment facility for a waste liquid of the binder and the organic solvent is required.

As described above, in the first and second methods, after the metallizing is performed, the insulating container and the sealing metal are brazed, so that not only the number of steps is increased, but also the bonding strength and airtightness are improved. Inferior.

On the other hand, in the third method, since the active metal enhances the wettability of the base material of the insulating container, no pressurization is required, and the active metal can be metallized with a strong bonding force to the base material. . However, the brazing material of the AgCuTi alloy is Ti alloy.
A homogeneous alloy cannot be obtained due to the solid solubility of the alloy.

Further, the AgCuTi alloy contains a relatively high Vickers (Hv) hardness of about 300 to 400 and a relatively high and granular CuTi phase (precipitate) in a soft AgCu matrix having a Vickers hardness (Hv) of about 100. ) May be scattered.

[0015] Therefore, in the process of processing this alloy into a plate, wire, or tube, the stress becomes non-uniform, and particularly in the case of a thin plate, a thin wire, or a thin-walled tube, breakage, cracks, and irregularities occur in the CuTi phase portion.

When a brazing material of a thin plate or a thin wire of an AgCuTi alloy is used for a brazing portion between the vacuum valve and the sealing member, a granular CuTi phase is scattered in the AgCu matrix of the brazing material, There is a case where segregation occurs in the Ti concentration.
Cracks and irregularities may occur. In addition, with a vacuum valve brazed with this brazing material, a sufficient joining force cannot be obtained or the joining force varies, so that the shutoff characteristics become unstable.

Therefore, without metallizing,
A one-step joining method of brazing a sealing fitting to an insulating container has been proposed (JP-A-59-32628). This method uses an Ag brazing material containing Ti or Zr as an active metal, or a brazing material obtained by stacking a thin plate of an active metal and an Ag brazing material. This one-step bonding method can reduce the number of steps because metalizing is not required.

However, even in this one-step bonding method, if the Ag brazing material does not sufficiently adhere to the sealing fitting or the insulating container, particularly the insulating container, there is a possibility that good bonding strength and airtightness cannot be obtained. Then, an object of the present invention is to obtain a vacuum valve which can maintain airtightness for a long period of time and exhibit the features of vacuum shutoff for a long period of time.

[0019]

According to the present invention, there is provided a fixed-side energizing shaft which is provided at one end of a sealing plate which is joined to both ends of an insulating container and maintains an internal vacuum, and which is advanced and retracted to the other side of the sealing plate. A vacuum valve comprising a movable-side energized shaft freely penetrated, and an electrode joined to a surface facing the movable-side energized shaft and the fixed-side energized shaft and coming and going when the movable-side energized shaft advances and retreats, is sealed. The brazing material for joining the plate to the insulating container is Ti / (Cu + Ti) 0.05-5.
% Of CuTi alloy and an Ag alloy containing Ag as a main component or an integrated material of Ag.

A vacuum valve according to the invention according to claim 2 is:
CuTi alloy from a molten state in a non-oxidizing atmosphere until the alloy solidifies, characterized by using a CuTi alloy manufactured by cooling at a rate of 50 to 10 ⁶ K / sec.

According to a third aspect of the present invention, there is provided a vacuum valve comprising:
The CuTi alloy is characterized in that 0.05 to 5% of Ti is dissolved in a Cu matrix. A vacuum valve according to a fourth aspect of the invention is characterized in that the CuTi alloy comprises a Cu matrix in which Ti is dissolved and a CuTi compound.

According to a fifth aspect of the present invention, there is provided a vacuum valve comprising:
The CuTi compound in the CuTi alloy is characterized in that the average interparticle distance of the precipitate is dispersed in the Cu matrix to 50 μm or less, and the size of the precipitate is 25 μm or less.

A vacuum valve according to a sixth aspect of the present invention comprises:
Ag is composed of (Ag + Cu), and this (Ag + C)
The ratio of Ag in u) is set to 30% or more. The vacuum valve of the invention according to claim 7, wherein Ag is:
(Ag + Cu + Pd).
AgCuPd in which the ratio of Ag in Pd) is 30% or more is characterized.

A vacuum valve according to the invention according to claim 8 is as follows.
Ag is obtained by adding at least one of In, Sn and Zn to Ag.
% Or more and 10% or less. Claim 9
In the vacuum valve of the invention corresponding to (Ag), Ag is (Ag + C
u) contains at least one of In, Sn, and Zn by 1% or more.
% Or less.

A vacuum valve according to the invention according to claim 10 is as follows:
Ag is characterized in that (Ag + Cu + Pd) contains at least one of In, Sn, and Zn at 1% or more and 10% or less.

The vacuum valve according to the present invention corresponds to claim 11:
Between the insulating container and the sealing plate, together with the brazing material obtained by integrating the CuTi alloy and Ag, the Cu containing no active metal is used.
And an intermediate layer made of Ag or Ag.

The vacuum valve according to the invention of claim 12 is:
It is characterized by combining and integrating CuTi and Ag. The vacuum valve of the invention according to claim 13 is CuTi
Ag is disposed on both surfaces of the substrate, and these are integrated.

A vacuum valve according to the invention according to claim 14 is:
It is characterized by combining and integrating a plate material, a wire material and a tube material of CuTi and Ag. Further, a vacuum valve according to the invention according to claim 15 is characterized in that the plate thickness, wire diameter and wall thickness of the tube material of the CuTi alloy are 30 μm to 150 μm.

Next, the operation of the vacuum valve brazed using the CuTi alloy and Ag of the present invention will be described.
Ti in Cu has a maximum solid solubility of about 5% by weight. Therefore, according to the study of the present inventors, good quality Cu
A Ti alloy can be obtained, and by combining this with heat treatment and processing, with a Ti content within a predetermined range, a C having good workability in which Ti is uniformly dispersed in a Cu matrix.
It was found that a uTi alloy was obtained.

Next, in order to adjust the melting temperature of the brazing material, Ag or AgCu is combined with a CuTi alloy to obtain a brazing material in which CuTi and Ag are integrated. The degree of integration is such that the two are melt-alloyed in the next joining step, so that the interface functions as a brazing material sufficiently even if the interface is in a diffusion state or a mere contact state, and a good joining material is obtained.

In the vacuum valve of the present invention, which is manufactured by hermetically brazing CuTi and Ag with a brazing material in which CuTi and Ag are integrated, [Ti / (Cu + Ti)] of CuTi alloy is used.
The reason for setting the value to 0.05 to 5% is that if it is 0.05% or less, CuTi precipitates in the matrix are also extremely small and become a substantially homogeneous material. This is because it is inferior in wettability and hardly joined.

On the other hand, if it exceeds 5%, a large amount of CuTi precipitates are present in the matrix, and some of them have a size exceeding 50 μm, and the distribution of these precipitates is remarkably segregated, so that they are used integrally with Ag. However, sufficient bonding strength cannot be obtained and the strength varies.

The reason why 0.05 to 5% of Ti is dissolved in the Cu matrix is that in this range, CuTi precipitates in the matrix can be uniformly distributed and the material having a solid solution amount of 5% or more is used. Is difficult to obtain.

Further, the C of the CuTi phase in the CuTi alloy
The reason why the particles are highly dispersed in the u matrix is that if the average interparticle distance of the precipitate is 50 μm or more, the strength after being integrated with and joined to Ag varies.

On the other hand, the upper limit of the size of the precipitate is 25 μm.
The reason for keeping it below m is that if it is 25 μm or more, stress concentrates on the precipitate during thin plate processing and fine wire processing, not only breaks, cracks and irregularities occur, but also precipitates with a higher melting temperature than the matrix are unevenly distributed. This is because the bonding strength varies.

It is preferable that the lower limit of the size of the precipitates includes those that are not visually recognizable with a metallographic microscope at a magnification of 300 times. until coagulation, 50~10 ⁶ K /
It is manufactured by cooling at a speed of seconds.

Further, Ag is expressed as (Ag + Cu), (Ag + C
u + Pd). With Ti, the rise in the melting temperature of the matrix can be suppressed, and the stress applied to the insulating container can be suppressed. About 1 to 10% of In, Sn, and Zn may be added to Ag. This can prevent the state where the wettability with the insulating container is reduced by Ti.

Further, (Ag + Cu) and (Ag + Cu +
30% or more (including 100% or more) of Ag in Pd)
The reason is to suppress the generation of the CuTi phase in the brazing material.

Further, (Ag + Cu) and (Ag + Cu)
+ Pd), at least one of In, Sn, and Zn is
The reason why the content is set to 1% or more and 10% or less with respect to (Ag + Cu) and (Ag + Cu + Pd) is that if it exceeds 10%, the workability as a brazing material is remarkably reduced.

The method of integrating the CuTi alloy with the Ag and Ag alloys may be, for example, merely stacking them. However, after the stacking, they are more firmly formed by caulking, pressing, rolling, extruding, forging or heat diffusion. It is preferable to integrate them securely.

The shape of the CuTi alloy, Ag, Ag alloy may be a wire, a rod, or a hollow (pipe) instead of a plate.
For example, after the CuTi alloy of the wire is inserted into the pipe-shaped Ag, it may be integrated by extrusion.

The plate thickness, wire diameter and wall thickness of the CuTi alloy are preferably at least 10 μm, more preferably at least 30 μm.
The reason is the ratio between the size (d) of the CuTi phase (precipitate) and the plate thickness (t). However, if the CuTi phase increases, it is not possible to obtain a preferable CuTi alloy plate, wire, or pipe. .

According to the experiment of the inventor, the ratio of d / t is
About 1/3 or less is preferable. Specifically, the thickness, wire diameter, and pipe thickness of the CuTi alloy should be 10 μm or more, if possible.
It is preferably at least 30 μm.

If Ag is arranged on both surfaces of CuTi and integrated, it is possible to prevent the material from being bent due to the bimetal effect after the integration. CuT inside tubular Ag
The same applies when i is inserted and integrated.

When the CuTi alloy and Ag are previously integrated by heat treatment, the heat treatment should be performed in a vacuum or a non-oxidizing atmosphere, and should be performed at a temperature equal to or lower than the solidus point of Ag and the Ag alloy.

The reason is that if the Ti is oxidized, the brazing property is reduced, so that the selective oxidation of the Ti during the integration is prevented. When integrated at a temperature higher than the solidus point, Ag, Ag
This is for promoting the movement of Ti in the Cu matrix and preventing the segregation and aggregation of Ti.

When the factors of the variation in the bonding strength were examined, the amount, thickness, and material of the brazing material, particularly the state of the brazing material, that is, cracks generated inside the brazing material, in addition to the surface condition of the insulating container, were examined. It was found that the influence of the progress and the uniformity of the structure related to the stress generated at the joint interface was large.

Among these, the uniformity of the structure depends on the amount and size of the CuTi phase inside the brazing material and the degree of segregation. These are determined by the atmosphere during the production of the brazing material (vacuum non-oxidizing property), melting conditions, It is affected by processing and rolling conditions and heat treatment conditions. Cu
The Ti phase may be generated in a process of rolling a CuTi ingot and in a brazing process.

In the latter, the brazing material is redissolved, so that the CuTi phase generated in the former brazing material manufacturing process disappears. Therefore, the CuTi phase generated in the brazing material manufacturing process is generally neglected. However, the vacuum valve of the present invention affects the workability when the CuTi plate and the Ag plate are integrated.

If the amount of the CuTi phase in the brazing material is too large, not only the composition is not uniform and the melting temperature varies, but also a poor quality brazing material cannot be obtained due to poor processing. As a result, the bonding force is reduced, and the cutoff characteristics are also reduced. In such a brazing material, the permeability of the joining surface is impaired, and the joining strength varies.

The brazing filler metal having a large amount of CuTi phase has low bonding strength, variation, and poor airtightness. In the micrograph of the cross section of the joint, a crack was observed in the direction of the insulating container from the CuTi phase or the vicinity.

On the other hand, in a joint using a brazing material having a low CuTi phase, cracks originating from the CuTi phase also occur, and some of the cracks extend to the insulating container. Less than the former.

It has been found that the state of the brazing material (the amount and the form of the CuTi phase) has a correlation with the time and the state of crack generation. This is considered to be a cause of the variation in the joining force.

Therefore, in order to reduce the variation,
It is important to control the state of the brazing material to be used in advance in order to improve the shutoff characteristics of the vacuum valve by stabilizing the joining force.

[0055]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the vacuum valve of the present invention will be described in detail. Frequency of re-ignition The frequency of re-ignition when a circuit of 6 kv 500 A is cut off and a break of 7.2 kV, 50 Hz when a disc-shaped contact with a diameter of 30 mm and a thickness of 5 mm is incorporated into an experimental vacuum valve. Limit value 2
Tables 1 and 2 include the variations of the vacuum circuit breakers (six vacuum valves). The power factor of the shutoff circuit is 1
It is.

[0056]

[Table 1]

[0057]

[Table 2]

At the time of mounting the contacts, only baking heating (450 ° C. × 30 minutes) was performed, and the brazing material was fixed to the electrodes with screws, and the use of the brazing material and the accompanying heating were not performed. Table 2
The test was conducted with the frequency of re-ignition being narrower than the contact gap at the time of the test for breaking magnification.

The number of cutoffs of 20,000 is the total of six vacuum valves, and the number of valves for which the test is stopped is also added. The lower limit value of the occurrence frequency indicates the minimum value of the six lines, and the upper limit value indicates the maximum value.

Breaking magnification A contact electrode was mounted on a vacuum valve for a breaking test, baking and current / voltage aging of the contact surface were performed, and after making the opening speed condition constant, the breaking current value was 5 kA at 7.2 kV, 50 Hz. The limiting current value was measured while increasing from.

As shown in Tables 1 and 2, the cut-off limit current value of Example 3 was set to 100, and compared with the value under each condition, the magnification was shown as the cut-off magnification. Next, CuTi shown in Table 1 was used for brazing a sealing metal fitting for a vacuum valve.
An alloy and an Ag or silver alloy were used.

The average surface roughness (Rave.) Is set to about 0.1 μm.
m, pre-heated at 1,450 ° C., and used an insulating container (main component: alumina). As a sealing metal, a 42 mm N 2 mm thick plate having a surface coated with Ni having a thickness of about 1 μm was used.
i-Fe alloy, Kovar, etc. were used.

The most important CuTi plate as a brazing member is to weigh Cu particles and Ti particles weighed to predetermined values at a degree of vacuum of 5 × 10 ^-4.
Pa. And then cooled in a vacuum atmosphere, and then combined with forging, rolling and heat treatment to form a CuT
An i plate was used.

A CuTi plate for precisely controlling the amount of Ti is a CTi plate.
A Ti layer having an accurate thickness was formed on the u-plate by plating, and both were uniformly alloyed by a thermal diffusion method or the like to obtain CuTi. Note that Ti
The layer may be formed by an ion plating method or a sputtering method.

As another method for producing a CuTi plate, for example, a 96% Cu-4% Ti alloy melt is sprayed on a rotating roll, and the cooling rate from the melt to the solid becomes 10 ⁴ K.
/ Solidification at a rate of about / second. Cu in this case
The microstructure of the Ti plate was uniform with almost no visible CuTi phase.

Next, a vacuum valve was manufactured by brazing with this CuTi alloy, Ag or the like. Of the methods of integrating the CuTi alloy and Ag, it is simple to simply overlap and caulk, but the insertion work between the insulating container and the sealing fitting is complicated, and the CuTi plate and Ag may be displaced. There is
The handling is inconvenient and the brazing process of the vacuum valve becomes complicated.

Then, if the two are firmly integrated by further applying pressure after the superposition, the handling becomes easy. Further, if the interface is metallurgically joined by heat treatment, the situation is further improved. When integrated by heat treatment, when the Ti is oxidized, the bonding strength is reduced. Therefore, in order to suppress the selective oxidation of the Ti, it was performed in a vacuum.

Further, they may be integrated by hot pressing or cold pressing at a temperature not higher than the solidus point of Ag or Ag alloy. When integrated at a temperature equal to or higher than the solidus point, Ti moves and aggregates in the Ag and Ag matrix that has become a liquid phase.
In some cases, restriking occurred.

Therefore, the CuTi plate and the A
In order to integrate g, selection of atmosphere and temperature is important. As a method of integrating the CuTi plate and the Ag, they may be partially joined by spot welding. In this method, the junction is partially formed, but there is no fear of migration or selective oxidation of Ti.

Next, the integrated (CuT)
The sealing portion was joined with a brazing material of i-alloy Ag) in a vacuum furnace at 860 ° C. for 20 minutes. Bonding was performed well in a non-oxidizing atmosphere such as argon gas and hydrogen gas, but bonding was not possible in an oxidizing atmosphere, or even if bonding could be performed, the strength varied.

Therefore, the integrated CuTi alloy Ag
Is particularly important to select the atmosphere during the bonding process. The state of adhesion of the silver solder after the brazing step was observed visually and by a micrograph of the interface of the joint.

The vacuum valve after the hermetically sealed attachment is attached to the jig,
The peeling force of the joint between the sealing fitting and the insulating container was measured at both ends using an Instron universal testing machine. 72% of the intensity of the AgCu brazing material 20~30kgf / mm ² or more was targeted.

In the vacuum valve according to the present invention, the integrated (CuTi alloy Ag) brazing material is, for example, about 1 mm thick.
And placed between the insulating container and the sealing fitting, that is, (CuTi alloy Ag) / Cu.

The Cu plate may be omitted or its thickness or number may be changed depending on the manufacturing conditions. The Cu plate suppresses oxidation of the CuTi alloy and generation of a NiTi compound when, for example, plating is performed on the surface of the sealing metal.

Further, in the vacuum valve of the present invention, the integrated CuTi alloy Ag brazing material is
The insulating container may be sandwiched between plates and disposed between the insulating container and the sealing fitting, that is, the insulating container may be brazed as Cu / CuTi alloy Ag / Cu. The Cu plate may be omitted or the thickness and the number of Cu plates may be changed depending on manufacturing conditions.

Examples 1-5, Comparative Examples 1-2 The Ti content (Ti / Cu + Ti) in the CuTi alloy was
The Cu and Ti raw materials weighed while varying in the range of 8.5% were vacuum melted by the high frequency induction melting method (Examples 1 to 3 and Comparative Example 1) and the electron beam melting method (Examples 4 to 5 and Comparative Example 2). The molten metal was poured into a water-cooled copper mold to produce a CuTi alloy ingot.

This ingot was forged, rolled, and annealed to produce a CuTi alloy plate having a thickness of 100 μm. As the Ag, a normal Ag plate was used. The brazing surface of the insulating container was polished to an average surface roughness (Rave.) Of about 0.1 μm.

The surface of the sealing member was made of Ni having a thickness of about 1 μm.
A coated 42% Ni-Fe alloy with a thickness of 2 mm was used.

The vacuum valve after brazing was mounted on a jig, and pulled from both sides with an Instron universal testing machine to measure the bonding strength. The CuTi alloy and Ag were placed between the insulating container and the sealing fitting, and joined at 860 ° C. for 20 minutes in a vacuum.

In some embodiments, the CuTi alloy and Ag were metallurgically integrated in advance, then placed between the insulating container and the sealing fitting, and joined in vacuum at 860 ° C. for 20 minutes. In another embodiment, a CuTi alloy and Ag were previously integrated by pressure bonding or the like, then placed between an insulating container and a sealing fitting, and joined at 860 ° C. for 20 minutes in a vacuum.

In another embodiment, CuTi
The alloy and Ag were integrated by a spot welder, placed between an insulating container and a sealing fitting, and joined at 860 ° C. for 20 minutes in a vacuum. In any case, a good vacuum valve was obtained.

As described above, in the present invention, Cu
Ti alloy and preferred Ti in CuTi alloy
The amount (Ti / Cu + Ti) value is preferably in the range of 0.05 to 5.0% (Examples 1 to 5).

Example 6, Comparative Examples 3 and 4 In Examples 1 and 5 and Comparative Examples 1 and 2, the effects and effects of the amount of Ti in the CuTi alloy when the thickness of the CuTi alloy was 100 μm were shown. .

However, when the (Ti / Cu + Ti) value is 0.5%
Assuming that the thickness of the CuTi alloy is 1 to 1000 μm, C
When the thickness of the uTi alloy is 1 to 5 μm (Comparative Examples 3 and 4),
During the manufacturing process of CuTi alloy plate, CuT in CuTi alloy
The ratio of the i-compound increases, stress concentrates on the CuTi compound, which may cause breakage during the processing of the CuTi alloy into a thin plate or a thin wire, resulting in poor workability in vacuum valve assembly and an insufficient amount of Ti. As a result, sufficient wettability could not be obtained at the joint surface of the vacuum valve, and re-ignition due to a vacuum leak occurred frequently.

On the other hand, when the thickness of the CuTi alloy is 10 μm
m or more (Examples 6 to 9), high-quality CuTi alloy Ag
Is obtained, and the joining strength when the insulating container and the sealing fitting are joined is excellent at 60 to 100 kgf / mm ² .

In this case, by observation with a microscope of the bonding interface after the brazing step, a good bonding portion was obtained without the amount of CuTi phase being small and the dispersion state being agglomerated. The size of the precipitate of the CuTi alloy was 25 μm or less. The average distance between precipitates was also 50 μm or less. Therefore, in the present invention, the thickness of the CuTi alloy is 10 μm
It is preferable to use the above (Examples 6 to 9).

Examples 10 to 11 and Comparative Examples 5 to 6 In Examples 1 to 9 and Comparative Examples 3 and 4, the CuTi alloy
Although the size of the Ti compound was in the range of 5 to 25 μm,
0.5% Ti content (Ti / Cu + Ti) in Ti alloy
Even when the thickness of the uTi alloy is 100 μm and the size of the CuTi compound is 5 μm or less and 5 to 25 μm,
As in No. 9, the frequency of occurrence of restriking was low, and the cutoff characteristics were stable (Examples 10 to 11).

On the other hand, the size of the CuTi compound is
When the thickness is 20 to 60 μm (Comparative Example 5) and 100 μm or more (Comparative Example 6), cracks or breaks occur at the interface between the CuTi precipitate and the matrix, so that a high-quality CuTi alloy cannot be obtained. Peeled from the interface.

When used for brazing a vacuum valve and a sealing fitting, the bonding force is 10 to 70 kgf / mm ² to 5 to 85 kgf / mm.
^The re-ignition test was stopped because some vacuum valves leaked due to the impact of opening and closing. The blocking characteristics were also extremely unstable.

Therefore, CuT in CuTi alloy
When the size of the i-compound was set to 25 μm or less, the cutoff characteristics with less occurrence of restriking were exhibited (Examples 10 to 11). In the above embodiment, the CuTi alloy was manufactured in advance, and then the CuTi alloy and Ag were integrated. However, the Cu plate and the Ti plate were not integrated with the CuTi alloy, but were sealed with the insulating container in a state where the Ag and the Ag were separately integrated. The method of arranging it between the metal fittings makes the operation complicated, but has little effect on the cutoff characteristics including restriking.

Examples 12 to 14 and Comparative Example 7 In Examples 1 to 11 and Comparative Examples 2 to 6, 100% Ag was used as Ag.
Cu remaining Ag, 28% Cu remaining Ag, 70% Cu remaining Ag
Also in Examples 12 to 14, the frequency of occurrence of restriking was low, and stable blocking characteristics were exhibited.

On the other hand, in the case of 85% Cu remaining Ag (Comparative Example 7), the amount of CuTi precipitates increased, and a variation in bonding force and poor airtightness occurred during the opening / closing operation. Bonding force is 15-75kgf / mm
Variations in the range of ² were observed by microscopic observation of the interface of the sealed part.
A large amount of coarse CuTi phase was found in the uTi alloy, and the size of some of them exceeded 50 μm (Comparative Example 7). Input
Due to the vibration at the time of opening, the airtightness of some vacuum valves decreased, re-ignition frequently occurred, and some valves could not be tested.

Examples 15 to 26 In Examples 1 to 11 and Comparative Examples 2 to 6, 100% A was used as Ag.
g, the example using AgCu as the Ag alloy was shown,
AgPd, AgCuPd, AgIn, A as Ag alloy
gSn, AgInSn, AgZn, AgCuIn, Ag
CuSn, AgCuInSn, AgCuZn (Example 15
26-26), a good CuTi alloy could be obtained, and good airtight bonding was obtained, and in each case, the breaking characteristics were less likely to cause re-ignition.

In the above embodiment, a plate-shaped CuTi alloy and A
g was used for integration, but both may be integrated. Further, the sealing metal fittings of the above Examples and Comparative Examples are made of Cu-Ni-based alloys (Ni 70 wt% or less, Ni-based alloys such as SUS304, 42 alloy or Kovar coated with Cu or Ni).
(Equipped with Ni = 0), the same cut-off characteristics were obtained. As the material of the insulating container, oxide ceramics such as magnesia and zirconia may be used in addition to alumina.

[0095]

According to the present invention, the brazing material for brazing the insulating container and the sealing plate is made of Cu and Ti beforehand.
Since Ag is integrated as an alloy, the distribution of Ti becomes more uniform than when AgCuTi alloy is manufactured and then as a plate or wire, and a vacuum valve that can maintain the characteristics of vacuum interruption for a long time is obtained. Can be.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C22C 9/00 C22C 9/00 (72) Inventor Rika Takikawa 1 Toshiba-cho, Fuchu-shi, Tokyo Toshiba Corporation Fuchu Plant

Claims (15)

[Claims] 1. A fixed-side energizing shaft which is joined to both ends of an insulating container and is provided on one side of a sealing plate for maintaining an internal vacuum, and a movable shaft which is provided on the other side of the sealing plate so as to be able to advance and retreat. A vacuum valve comprising: a side energizing shaft; and an electrode which is joined to an opposing surface of the movable side energizing shaft and the fixed side energizing shaft and which comes into contact with and separates from the movable side energizing shaft. The brazing material to be joined to the container is Ti / (Cu + Ti) 0.05-5%
A vacuum valve characterized by being an integrated material of a CuTi alloy described above, and an Ag alloy or Ag containing Ag as a main component. Wherein said CuTi alloy from a molten state in a non-oxidizing atmosphere until the alloy solidifies, 50 to 10 ⁶ K /
The vacuum valve according to claim 1, wherein a CuTi alloy manufactured by cooling at a speed of seconds is used. 3. The CuTi alloy contains 0.05 to 5% of Ti.
3. The vacuum valve according to claim 1, wherein is dissolved in a Cu matrix. 4. The CuTi alloy has a solid solution of Ti
The vacuum valve according to any one of claims 1 to 3, wherein the vacuum valve comprises a u matrix and a CuTi compound. 5. The CuTi compound in the CuTi alloy has an average interparticle distance of the precipitate of 50 in the Cu matrix.
μm or less, and the size of the precipitate is 25 μm
The vacuum valve according to claim 1 or 2, wherein: 6. The vacuum valve according to claim 1, wherein the Ag is composed of (Ag + Cu), and a ratio of Ag in the (Ag + Cu) is 30% or more. 7. The Ag is composed of (Ag + Cu + Pd), and the ratio of Ag in the (Ag + Cu + Pd) is 30.
%. The vacuum valve according to claim 1, wherein the alloy is an AgCuPd alloy having a percentage of at least%. 8. The vacuum valve according to claim 1, wherein the Ag contains at least one of In, Sn, and Zn with respect to Ag by 1% or more and 10% or less. 9. The method according to claim 9, wherein the Ag is In, S in (Ag + Cu).
3. The vacuum valve according to claim 1, wherein at least one of n and Zn is contained in a range of 1% to 10%. 10. The vacuum valve according to claim 1, wherein the Ag contains (Ag + Cu + Pd) at least one of In, Sn, and Zn in a range of 1% or more and 10% or less. 11. Between the insulating container and the sealing plate,
The vacuum valve according to claim 1 or 2, wherein an intermediate layer made of Cu or Ag containing no active metal is interposed with the brazing material obtained by integrating the CuTi alloy and Ag. 12. The vacuum valve according to claim 1, wherein the CuTi and the Ag are combined and integrated. 13. The vacuum valve according to claim 1, wherein the Ag is disposed on both surfaces of the CuTi, and the Ag is integrated. 14. The method according to claim 1, wherein said CuTi and said Ag of a plate material, a wire material, and a tube material are combined and integrated.
A vacuum valve according to claim 11. 15. The vacuum valve according to claim 14, wherein a plate thickness, a wire diameter, and a wall thickness of the CuTi alloy are 30 μm to 150 μm.