JPH0551130B2

JPH0551130B2 -

Info

Publication number: JPH0551130B2
Application number: JP62206002A
Authority: JP
Inventors: Ryuji Watanabe; Hisashi Ando; Seiki Shimizu; Mitsuo Nakamura; Kyoji Iwashita
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 1987-08-19
Filing date: 1987-08-19
Publication date: 1993-07-30
Also published as: JPS6450336A

Description

[Detailed description of the invention]

〔産業上の利用分野〕本発明は、遮断器用電極に係り、特に大容量電
力用高耐電圧性を要する電極に好適な真空遮断器
用電極に関する。〔従来の技術〕真空遮断器は、10^-7torr程度の高真空を維持し
た容器（真空バルブ）内で接点電極の取り付けら
れた両接触子の開閉を行うものである。高真空中の絶縁耐力は非常に高いので、開閉ス
トローク、すなわちギヤツプは他の型の遮断器に
比べ、極端に短かいのが特徴である。真空遮断器の電極材料として具備すべき主要な
電気的性能は、(イ)耐電圧性が高いこと、(ロ)耐溶着
性が高いこと、(ハ)電流遮断性能が高いこと、(ニ)接
触抵抗が小さいこと、等である。従来、それぞれの特性のより優れた電気材料を
追求して、研究が続けられてきた。真空遮断器用電極材料としては、従来は溶解法
によつて作られるCuベースの合金、あるいは特
開昭54−73284号公報のような粉末冶金的に作ら
れるWC−Ag系や、特公昭45−35101号公報に開
示されているようなCr−Cu系溶浸合金が一般的
である。特に、後者のCr−Cu系溶浸合金は、低
融点金属を含まなくとも耐溶着性が優れることか
ら、現在では大容量用真空遮断器の電極に多く用
いられつつある。すなわち、上記のごとく、従来
材料においてはいずれのものも銅、もしくは銀を
含んだものであることがわかる。従来から、多くの種類の電気接点材料には通電
性をよくするために銅や銀が含有され、同様に真
空遮断器電極も同じ思想で材料開発がなされてき
た。しかし、受変電設備が大容量化、あるいは高
耐電圧化の方向にある最近では、電極接点部にか
かる各種電気的能力に関してより性能改善が望ま
れている。とりわけ、耐電圧性の改良は、高耐電
圧真空遮断器を開発するうえでとりわけ重要であ
る。なお、耐電圧性が向上すれば、電極間隙を挟
ばめることができ、操作系統の一層の小型化も図
れる。そこで、従来から銅や銀に各種高耐電圧元素
（例えば、コバルト、クロム、ジルコニウムなど）
を添加したものや、クロムをマトリクスとし銅を
溶浸させたような各種電極接点材料が開発されて
きた。真空遮断器が米国GE社の研究により開発され
て以来約60年経過するが、その間、各種の接点材
料が見い出され、実用化もされてきたが、ほとん
どの材料、特に実用化に至つたものにおいては、
銅もしくは銀をベースとした材料であつた。この
ため、耐電圧性能に限界があつた。すなわち、銅
や銀は、もともと耐電圧性は高くない元素であ
り、これがマトリツクスであるということは、究
極的に性能は上がらないということである。これ
を改良すべく、クロム焼結マトリツクスを用いた
Cr−（10〜30）重量％Cu溶浸材料（特公昭45−
35101号公報）などは、中でも優れた材料という
ことができた。〔発明が解決しようとする問題点〕しかしながら、真空遮断器の大容量化あるいは
高耐電圧化のためには、現在の銅や銀を含む電極
材料では、耐電圧性を現状以上に向上させること
は困難であるという問題があつた。本発明の目的は、遮断性能、耐溶着性、接触抵
抗を従来並みに維持したままで、優れた耐電圧性
を有する真空遮断器用電極を提供することにあ
る。〔問題点を解決するための手段〕本発明の目的は、真空中で対向して設けられた
一対の電極の間隙を開閉させることにより前記電
極間の電流の遮断および通電を行う真空遮断器用
電極において、鉄、ニツケル、コバルトおよびク
ロムのうち少なくとも１種の金属とアルミニウム
との化合物からなるマトリツクス中に、クロム、
ジルコニウム、チタン、ニオブ、マンガン、モリ
ブデン、タンタルおよびシリコンのうち少なくと
も１種の金属からなる耐熱性金属粒子を均一に分
散して析出させた電極材料からなることを特徴と
する真空遮断器用電極を提供することにより達成
される。〔作用〕鉄、ニツケル、コバルトおよびクロムの少なく
とも１種の金属とアルミニウムとの化合物は、融
点が高く、導電性が良好であることのほかに、高
温で熱電子を放出しにくく、また蒸気圧が高くな
いので、放電を起こしにくい。また、この化合物は、非常に硬い物質であつ
て、この化合物のみでは電接部の接触面積が大き
くならないが、前記化合物のマトリツクス全域に
均一に分散して析出させたクロム、ジルコニウ
ム、チタン、ニオブ、マンガン、モリブデン、タ
ンタルおよびシリコンのうち少なくとも１種の金
属からなる耐熱性金属粒子は、脆弱な物質粒子な
ので、真空遮断器電極の閉極時の衝撃力によつて
押しつぶされ、あるいは壁壊し、電接部分の間隙
を平均的に埋めつくし、接触面積を広げる。また、上記耐熱性金属粒子は、脆弱な物質粒子
であることから、遮断時に電接部分がはがれやす
い。〔実施例〕上記目的に対し、本発明者らは、銅に代替でき
しかも高耐電圧、高融点系の物質を探索してみ
た。高耐電圧用元素としては、クロムの他に鉄族
元素（鉄、ニツケル、コバルト）が代表的であ
る。一般に、融点が高く、材質的に硬さの大なる
ものが高耐電圧性を有する。しかし、モリブデ
ン、タングステン、タンタルなどは、それ自身が
高温で熱電子放射率が高く、いわばフイラメント
材のようなもので、真空遮断器用電極としては絶
縁回復特性が悪く、大容量できないという難点が
ある。この例として、Cu−ＷやAg−ＷやAg−
WC系接点が知られるが、いずれも高耐電圧用あ
るいは大容量用としてはあまり用いられていな
い。以上のような理由に対し、本発明者らは、高耐
電圧物質として、クロムの他に鉄族元素の金属間
化合物を取り上げてみた。本発明では、特によく
知られている高融点化合物の中から、NiAlや
Ni₃Alを第１例にして、高耐電圧接点材料への適
用を検討してみた。すなわち、銅の代替としてNi₃Alなどを適用
し、例えばNi₃Al−Cr系の新規な電極材料を取り
上げてみた。鉄、ニツケル、コバルトおよびクロムの少なく
とも１種の金属とアルミニウムとの化合物は、単
に融点が高いというだけでなく、化合物自体が導
電性が良好である。すなわち、電極としては高耐
電圧性の他に通電能力がなければならない。例え
ば、NiAl化合物においては、これ自体で約８〜
10IACS％の導電率を有するものである。本発明
者らの経験では、この程度の導電性があれば電極
接点として用いることが可能なことがわかつてい
る。例えば、特願昭57−47423号公報に開示した
ようなCo−Ag−Se系材料においても７〜
10IACS％であるが、その材料が汎用（7.2kV級）
真空遮断器として十分使いうることを確認してい
るからである。以上がNiAl系などの金属間化合物が電極材料
として用いることができることの説明であるが、
真空遮断器用電極とするには、他に重要な諸性質
を満足させなければならない。中でも、耐溶着性
と接触抵抗の問題である。すなわち、NiAl化合
物が1638℃という高い融点を有するにしても、真
空遮断器用電極として用いた場合、遮断時に発生
するアークにより、短時間ではあるが約2000〜
2500℃にも達し、電接部分の溶着を皆無にするこ
とはできない。そこで、本発明ではNiAlなどの
マトリツクス全域に、クロム、チタン、ジルコニ
ウムなどの脆弱な物質粒子を分散配置しようとい
うものである。この構成は、前述した特公昭45−
35101号公報のCr−Cu系材料のクロムの役割と同
じと考えてよい。クロムの役割は、溶着性の改善のみならず、接
触抵抗の低減化にも効いている。なぜならば、
NiAlやNi₃Al化合物は、前記したように非常に
硬い物質であることから、接触抵抗が大きいとい
う問題がみられた。しかし、このマトリツクス中
にクロムが均一に分散していると、このクロム粒
子が電接部において、緩衝材的な効果を発揮す
る。すなわち、硬い化合物マトリツクス中に分散
されているクロムなどの耐熱性粒子は、真空遮断
器用電極の閉極時の衝撃力によつて押しつぶさ
れ、あるいは壁壊し、電接部分の間隙を平均的に
埋めつくしてくれるため、接触面積を広げ、この
結果、接触抵抗を下げるという効果をもつようで
ある。以上述べたように、耐電圧の高い化合物マトリ
ツクスに耐溶着性および接触抵抗低減能力を持た
せたクロムなどの耐熱性金属を分散させた材料
は、従来の銅、銀を含んだものに比べて優れた高
耐電圧性を有することがわかり、しかも他の真空
遮断器用電極としての諸性質も満足することがわ
かつた。なお、Ni₃AlやNiAl化合物と似たような特性
を示すものとして、CrAl、CoAl、TiAl、FeAl、
VAl₃、Mo₃Alなども取り上げることができ、さ
らに耐熱性の分散粒子もクロムの他にニオブ、チ
タン、ジルコニウム、マンガン、モリブデン、タ
ンタル、シリコンなどを適用することが可能であ
る。以下に、本発明の実施例の詳細について第１図
〜第７図により説明する。第１実施例 Ni₃Al−Cr系の材料の場合は、基本的には真空
溶解法が適用できる。すなわち、NiとAlが化合
物組成となるように配合し、Crを所定量添加す
ればよい。NiとAlの方が親和力が大きいため、
通常の鋳込操作を行つた場合、Crを均一に分散
させるためには、1000〜1200℃高温で均質化焼鈍
を加える必要がある。上記のごとく、真空溶解法によりNi₃Al−Cr系
材料を金型鋳造し、真空中で均質化焼鈍を行つた
のち、それらの合金から直径20mm、厚さ10mmの電
極を２こずつ採取した。上記材料を、第３図に示すような真空バルブに
組み込み、各種遮断特性を調べた。第２図に示す
真空バルブは、組立式排気セツト型の真空バルブ
試験機で、絶縁筒１の両端に端子板２，３を取り
付けて気密構造を形成し、排気管１０から排気し
て高真空とするもので、その両端子板２，３を貫
通して両電極ホルド４，５が取り付けられ、一方
の電極のホルダ４は、軸方向に摺動可能であり、
両電極ホルダの先端部には、補助電極材６，７が
設けられ、それぞれの補助電極材６，７には接点
電極８，９が固定され、その電極として上記の試
験材料を取り付けて開閉することにより、試験を
行う装置である。電気的性能試験としては、耐電
圧性試験、電流遮断性能試験、耐溶着性試験を行
つた。耐電圧性試験は、交流電流300Aを10回遮断す
ることによつて接点電極表面をクリーニング後、
インパルス電圧を5kVステツプで印加し、放電す
る電圧を測定した。このときの接点電極間隙を
2.5mmとした。電流遮断性能試験は、直径20mmの接点電極を用
い、遮断できる電流容量を調べるもので、0.5kV
ステツプで印加し、開極後１サイクル以内で電流
が零になる最大電流値である遮断限界電流値を求
めた。耐溶着性試験は、接点電極に溶着を生じ開極不
能となつたものについてのみ、上記排気セツトよ
り取り外し、引張試験機により溶着力を測定し
た。本発明のNi₃Al−Cr系材料のCr添加量と耐電圧
性および遮断性能との相関性に関する試験結果を
第１図および第２図に示す。第１図では、Ni₃AlへのCrの添加量を増やすほ
ど耐電圧値が大幅に上昇し、Cr量が５％以上で
効果が現われ、30％でほぼ最大値に達し、それ以
上Crを添加しても耐電圧値は飽和して上昇幅は
小さくなるが、約60％までは高い耐電圧値を示
す。第２図では、Ni₃AlへのCrの添加量を約60％ま
で増やすほど電流遮断性能は上昇するが、その上
昇幅は小さい。本発明材と比較材について、その電気的性能試
験を行つた結果を、第１表に示す。 [Industrial Field of Application] The present invention relates to an electrode for a circuit breaker, and particularly to an electrode for a vacuum circuit breaker suitable for an electrode that requires high voltage resistance for large-capacity power. [Prior Art] A vacuum circuit breaker opens and closes both contacts to which contact electrodes are attached in a container (vacuum valve) that maintains a high vacuum of about 10 ^-7 torr. Because the dielectric strength in high vacuum is extremely high, the opening/closing stroke, or gap, is extremely short compared to other types of circuit breakers. The main electrical properties that the electrode material of a vacuum circuit breaker should have are (a) high voltage resistance, (b) high welding resistance, (c) high current interrupting performance, and (d) The contact resistance is low, etc. Research has continued in the past in pursuit of electrical materials with better characteristics. Conventionally, electrode materials for vacuum circuit breakers include Cu-based alloys made by melting, WC-Ag-based alloys made by powder metallurgy as disclosed in Japanese Patent Application Laid-open No. 73284/1984, and A Cr--Cu based infiltration alloy as disclosed in Japanese Patent No. 35101 is common. In particular, the latter Cr--Cu based infiltration alloy has excellent welding resistance even without containing a low-melting point metal, and is now increasingly being used for electrodes of large-capacity vacuum circuit breakers. That is, as mentioned above, it can be seen that all conventional materials contain copper or silver. Conventionally, many types of electrical contact materials have contained copper or silver to improve conductivity, and materials for vacuum circuit breaker electrodes have also been developed based on the same idea. However, in recent years, as power receiving and transforming equipment has become larger in capacity or in the direction of higher withstand voltage, it is desired to improve the performance of various electrical capacities of electrode contact portions. In particular, improvement in voltage resistance is particularly important in developing high voltage withstand vacuum circuit breakers. Note that if the voltage resistance is improved, the electrode gap can be narrowed, and the operation system can be further miniaturized. Therefore, various high-voltage elements (e.g., cobalt, chromium, zirconium, etc.) have been added to copper and silver.
A variety of electrode contact materials have been developed, including those containing chromium as a matrix and infiltrated with copper. Approximately 60 years have passed since the vacuum circuit breaker was developed through research by GE in the United States, and during that time, various contact materials have been discovered and put into practical use, but most of the materials, especially those that have been put into practical use. In,
It was a copper- or silver-based material. For this reason, there was a limit to the withstand voltage performance. In other words, copper and silver are elements that do not originally have high voltage resistance, and the fact that they are used as a matrix means that ultimately the performance will not improve. In order to improve this, we used a chromium sintered matrix.
Cr-(10~30)wt% Cu infiltration material (Special Publication 1974-
35101) were among the most excellent materials. [Problems to be solved by the invention] However, in order to increase the capacity or withstand voltage of a vacuum circuit breaker, it is necessary to improve the voltage withstand property of the current electrode materials containing copper and silver. The problem was that it was difficult. An object of the present invention is to provide an electrode for a vacuum circuit breaker that has excellent voltage resistance while maintaining breaking performance, welding resistance, and contact resistance at the same level as conventional electrodes. [Means for Solving the Problems] An object of the present invention is to provide an electrode for a vacuum circuit breaker, which cuts off and conducts current between the electrodes by opening and closing a gap between a pair of electrodes provided facing each other in a vacuum. Chromium,
Provided is an electrode for a vacuum circuit breaker characterized by being made of an electrode material in which heat-resistant metal particles made of at least one metal selected from zirconium, titanium, niobium, manganese, molybdenum, tantalum, and silicon are uniformly dispersed and precipitated. This is achieved by [Function] Compounds of aluminum and at least one of the metals iron, nickel, cobalt, and chromium have a high melting point and good conductivity. In addition, they do not easily emit thermoelectrons at high temperatures, and have a low vapor pressure. Since the temperature is not high, it is difficult to cause discharge. Furthermore, this compound is a very hard substance, and although this compound alone does not increase the contact area of the electrical contact, chromium, zirconium, titanium, and niobium are uniformly dispersed and precipitated throughout the matrix of the compound. Heat-resistant metal particles made of at least one metal among manganese, molybdenum, tantalum, and silicon are fragile material particles, so they are crushed or wall-broken by the impact force when the vacuum circuit breaker electrode is closed. It evenly fills the gaps between electrically connected parts and expands the contact area. Furthermore, since the heat-resistant metal particles are fragile material particles, the electrically connected portions are likely to peel off when the connection is interrupted. [Example] For the above purpose, the present inventors searched for a material that can be substituted for copper and has a high withstand voltage and a high melting point. In addition to chromium, typical elements for high voltage resistance include iron group elements (iron, nickel, and cobalt). Generally, materials with a high melting point and high hardness have high voltage resistance. However, molybdenum, tungsten, tantalum, etc. are themselves high in temperature and have a high thermionic emissivity, so they are like filament materials, so they have poor insulation recovery characteristics and cannot be used as electrodes for vacuum circuit breakers, making them incapable of large capacity. . Examples of this include Cu-W, Ag-W, and Ag-
Although WC type contacts are known, they are not used very often for high withstand voltage or large capacity applications. For the above-mentioned reasons, the present inventors took up intermetallic compounds of iron group elements in addition to chromium as high voltage withstand substances. In the present invention, NiAl and
Using Ni ₃ Al as a first example, we investigated its application to high voltage contact materials. That is, we applied Ni ₃ Al as a substitute for copper, and took up, for example, a new Ni ₃ Al-Cr based electrode material. A compound of aluminum and at least one metal of iron, nickel, cobalt, and chromium not only has a high melting point but also has good electrical conductivity. That is, the electrode must not only have high voltage resistance but also have current carrying capacity. For example, in a NiAl compound, it itself has a
It has a conductivity of 10IACS%. According to the experience of the present inventors, it has been found that a material having this level of conductivity can be used as an electrode contact. For example, in Co-Ag-Se based materials as disclosed in Japanese Patent Application No. 57-47423,
10IACS%, but the material is general purpose (7.2kV class)
This is because we have confirmed that it can be used satisfactorily as a vacuum circuit breaker. The above is an explanation that intermetallic compounds such as NiAl-based can be used as electrode materials.
In order to be used as an electrode for a vacuum circuit breaker, other important properties must be satisfied. Among these problems are welding resistance and contact resistance. In other words, even though the NiAl compound has a high melting point of 1,638°C, when used as an electrode for a vacuum circuit breaker, the arc generated when the circuit is broken will cause the melting point to melt for a short period of time at approximately 2,000°C.
The temperature reaches 2500℃, making it impossible to completely eliminate welding of electrically connected parts. Therefore, in the present invention, particles of a brittle material such as chromium, titanium, or zirconium are dispersed throughout the matrix such as NiAl. This configuration is based on the above-mentioned
It can be considered that the role of chromium in the Cr-Cu-based material in Publication No. 35101 is the same. The role of chromium is not only to improve weldability but also to reduce contact resistance. because,
Since NiAl and Ni ₃ Al compounds are very hard substances as described above, there has been a problem of high contact resistance. However, when chromium is uniformly dispersed in this matrix, the chromium particles exhibit a buffering effect at the electrical contact. In other words, heat-resistant particles such as chromium, which are dispersed in a hard compound matrix, are crushed or broken by the impact force when the vacuum circuit breaker electrode is closed, and fill the gaps between electrical connections evenly. This seems to have the effect of increasing the contact area and lowering the contact resistance. As mentioned above, materials in which heat-resistant metals such as chromium, which have adhesion resistance and contact resistance reduction ability, are dispersed in compound matrices with high withstand voltage, are superior to conventional materials containing copper and silver. It was found that it had excellent high voltage resistance, and also satisfied various properties as an electrode for other vacuum circuit breakers. In addition, CrAl _, CoAl, TiAl, FeAl,
VAl ₃ , Mo ₃ Al, etc. can also be used, and in addition to chromium, niobium, titanium, zirconium, manganese, molybdenum, tantalum, silicon, etc. can also be used as heat-resistant dispersed particles. Below, details of embodiments of the present invention will be explained with reference to FIGS. 1 to 7. First Embodiment In the case of Ni ₃ Al-Cr based materials, basically a vacuum melting method can be applied. That is, Ni and Al may be blended to form a compound composition, and Cr may be added in a predetermined amount. Since Ni and Al have greater affinity,
When performing normal casting operations, it is necessary to add homogenization annealing at a high temperature of 1000 to 1200°C in order to uniformly disperse Cr. As mentioned above, Ni ₃ Al-Cr based materials were cast into molds using the vacuum melting method, homogenized annealed in vacuum, and then two electrodes with a diameter of 20 mm and a thickness of 10 mm were collected from each of the alloys. . The above material was incorporated into a vacuum valve as shown in FIG. 3, and various shutoff characteristics were investigated. The vacuum valve shown in Fig. 2 is an assembled exhaust set type vacuum valve testing machine, in which terminal plates 2 and 3 are attached to both ends of an insulating tube 1 to form an airtight structure, and the vacuum valve is evacuated from an exhaust pipe 10 to create a high vacuum. Both electrode holders 4 and 5 are attached through both terminal plates 2 and 3, and the holder 4 of one electrode is slidable in the axial direction,
Auxiliary electrode materials 6 and 7 are provided at the tips of both electrode holders, contact electrodes 8 and 9 are fixed to each of the auxiliary electrode materials 6 and 7, and the above test materials are attached as the electrodes to open and close them. This is the device that performs the test. As electrical performance tests, a withstand voltage test, a current interrupting performance test, and a welding resistance test were conducted. In the voltage resistance test, after cleaning the contact electrode surface by interrupting 300 A of alternating current 10 times,
Impulse voltage was applied in 5 kV steps and the discharge voltage was measured. The contact electrode gap at this time is
It was set to 2.5mm. The current interruption performance test uses a contact electrode with a diameter of 20mm to examine the current capacity that can be interrupted, and is 0.5kV.
The current was applied in steps, and the breaking limit current value, which is the maximum current value at which the current becomes zero within one cycle after opening, was determined. In the welding resistance test, only those whose contact electrodes were welded and could no longer be opened were removed from the exhaust set and the welding force was measured using a tensile tester. Test results regarding the correlation between the amount of Cr added in the Ni ₃ Al--Cr-based material of the present invention, withstand voltage property, and interrupting performance are shown in FIGS. 1 and 2. Figure 1 shows that as the amount of Cr added to Ni ₃ Al increases, the withstand voltage value increases significantly, and the effect appears when the amount of Cr is 5% or more, reaches almost the maximum value at 30%, and when Cr is added further Even if it is added, the withstand voltage value will be saturated and the increase will be small, but it will show a high withstand voltage value up to about 60%. In Figure 2, as the amount of Cr added to Ni ₃ Al increases to about 60%, the current interrupting performance increases, but the extent of the increase is small. Table 1 shows the results of electrical performance tests conducted on the materials of the present invention and comparative materials.

〔Effect of the invention〕

本発明の構成によれば、鉄、ニツケル、コバル
トおよびクロムの少なくとも１種の金属とアルミ
ニウムとの化合物は、融点が高く導電性が良好で
あることの他に、高温で熱電子を放出しにくく、
また蒸気圧が高くないので、放電を起こしにく
い。そのため、耐電圧性が向上する。前記化合物のマトリツクス全域に、均一に分散
して析出した金属粒子は、脆弱な物質粒子なの
で、真空遮断器用電極の閉極時の衝撃力によつて
押しつぶされ、接触面積を広げるので接触抵抗が
増大せず、また上記耐熱性金属粒子は、脆弱な物
質粒子であることから、電流遮断時に電接部分が
はがれやすいので、遮断性能および耐溶着性が十
分確保できる。本発明による電極を用いることによつて、真空
遮断器のより高耐電圧化が実現でき、また従来タ
イプの真空遮断器に適用する場合は、電極ギヤツ
プをさらにつめることが可能となり、超小型化も
達成される。 According to the structure of the present invention, the compound of aluminum and at least one metal of iron, nickel, cobalt, and chromium has a high melting point and good conductivity, and is difficult to emit thermoelectrons at high temperatures. ,
Also, since the vapor pressure is not high, it is difficult to cause electrical discharge. Therefore, voltage resistance is improved. The metal particles uniformly dispersed and precipitated throughout the compound matrix are fragile material particles, so they are crushed by the impact force when the vacuum circuit breaker electrode is closed, expanding the contact area and increasing the contact resistance. Moreover, since the heat-resistant metal particles are brittle material particles, the electrically connected portions are likely to peel off when the current is interrupted, so that sufficient interrupting performance and welding resistance can be ensured. By using the electrode according to the present invention, it is possible to achieve higher voltage withstand voltage in vacuum circuit breakers, and when applied to conventional vacuum circuit breakers, it is possible to further tighten the electrode gap, resulting in ultra-compact size. is also achieved.

[Brief explanation of drawings]

第１図は本発明によるNi₃Alへのクロム添加量
と耐電圧値の相関性についての試験結果を示す図
であり、第２図は本発明材によるNi₃Alへのクロ
ム添加量と電流遮断性能との相関性についての試
験結果を示す図であり、第３図は本発明材料を接
点電極として組み込むための真空バルブ試験機の
概略構造を示す断面図であり、第４図ａおよび第
４図ｂはそれぞれ本発明によるNi₃Al−10Crおよ
びNi₃Al−30Crの金属組織を示す写真であり、第
５図ａおよび第５図ｂはそれぞれ本発明による
Ni₃Al−10ZrおよびNi₃Al−30Zrのの金属組織を
示す写真であり、第６図ａおよび第６図ｂはそれ
ぞれ本発明によるNi₃Al−10TiおよびNi₃Al−
30Tiの金属組織を示す写真であり、第７図ａお
よび第７図ｂはそれぞれ本発明によるNi₃Al−
10NbおよびNi₃Al−30Nbの金属組織を示す写真
である。 Figure 1 shows test results on the correlation between the amount of chromium added to Ni ₃ Al and the withstand voltage value according to the present invention, and Figure 2 shows the relationship between the amount of chromium added to Ni ₃ Al and the electric current using the material of the present invention. FIG. 3 is a cross-sectional view showing the schematic structure of a vacuum valve testing machine for incorporating the present invention material as a contact electrode, and FIG. 4 a and FIG. Figure 4b is a photograph showing the metal structure of Ni ₃ Al-10Cr and Ni ₃ Al-30Cr according to the present invention, respectively, and Figures 5a and 5b are photographs respectively showing the metal structure of Ni 3 Al-10Cr and Ni 3 Al-30Cr according to the present invention.
FIGS _. 6a and 6b are photographs showing the metallographic structures of Ni ₃ Al-10Zr and Ni ₃ Al-30Zr, _respectively .
7a and 7b are photographs showing the metal structure of 30Ti, and FIGS. 7a and 7b are photographs showing the metal structure of _30Ti , respectively.
It is a photograph showing the metal structure of 10Nb and Ni ₃ Al-30Nb.

Claims

[Scope of Claims] 1. An electrode for a vacuum circuit breaker that cuts off and passes current between the electrodes by opening and closing a gap between a pair of electrodes provided oppositely in a vacuum, comprising iron, nickel, cobalt, and chromium. Heat-resistant metal particles made of at least one metal among chromium, zirconium, titanium, niobium, manganese, molybdenum, tantalum, and silicon are uniformly dispersed in a matrix made of a compound of at least one metal among aluminum and aluminum. An electrode for a vacuum circuit breaker, characterized in that it is made of an electrode material deposited by 2 The heat-resistant metal has 5 to
The electrode for a vacuum circuit breaker according to claim 1, characterized in that it contains 60% by weight. 3. The electrode for a vacuum circuit breaker according to claim 2, wherein the heat-resistant metal is chromium. 4. The electrode for a vacuum circuit breaker according to claim 1 or 2, wherein the compound is made of either NiAl or Ni ₃ Al.