JPS59201331A - Contact material for vacuum breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a contact material for a vacuum breaker that has excellent large current breaking performance and good withstand voltage performance.

Vacuum circuit breakers have advantages such as maintenance-free, non-polluting properties, and excellent breaker performance, so the range of applications of vacuum circuit breakers is rapidly expanding. Additionally, along with this, larger breaking capacity and higher withstand voltage are required.

On the other hand, the performance of a vacuum breaker is determined to a large extent by the contact material inside the vacuum vessel.The characteristics that should be satisfied with the contact material for a vacuum breaker are (1) large breaking capacity; ) High withstand voltage, (3) Low contact resistance, (4) Low welding force, (5) Low contact wear, (6) Low cutting current value, (7) Processing (8) have sufficient mechanical strength; and (8) have sufficient mechanical strength.

In actual contact materials, it is quite difficult to satisfy all of these properties, and in general, materials that satisfy particularly important properties depending on the application and sacrifice other properties to some degree are used. The reality is that

Conventionally, copper-bismuth (hereinafter referred to as 0u
-Display as Bi. Materials consisting of other elements and combinations of elements are similarly indicated with element symbols), 0u
-Or-Bi, 0u-Co-Bi, 0u-Or, etc. were used. However, in a contact containing a low melting point metal such as (!u-Bi), a portion of the metal diffuses and evaporates from within the contact due to high temperature heating during the evacuation process, and adheres to the metal shield or insulating container in the vacuum container. This is one of the major factors that deteriorate the withstand voltage of the vacuum breaker.
Evaporation and scattering of low-melting point metals occur during load switching and large current interruption, resulting in deterioration of withstand voltage and deterioration of interruption performance.

To eliminate the above drawbacks, we use Or, O, which has excellent vacuum withstand voltage.
Even in the case of Ou-Or-Bi added with O, etc., the above drawbacks cannot be fundamentally solved by using a low melting point metal, and it cannot cope with high voltage and large current. On the other hand, materials such as 0u-Or, which are made of a combination of metals (Or, Co, etc.) with excellent vacuum withstand voltage and O, which has excellent electrical conductivity, are inferior to contact materials containing low melting point metals in terms of welding resistance. Although it is slightly inferior to , it has excellent breaking performance and withstand voltage performance, so it is often used in high voltage, large forces, and river areas.

Furthermore, 0u-C! Since there is a limit to the breaking performance of the r, etc., by devising the shape of the contact and manipulating the current path of the contact, a magnetic field is generated, and this force forcibly drives a large current arc, which can be used to break the current. Efforts were made to improve performance.

However, the demands for larger currents and higher voltages have become even more demanding, making it difficult to fully satisfy the required performance with conventional contact materials. Similarly, in order to miniaturize vacuum breakers, the performance of conventional contacts was insufficient, and there was a need for contact materials with even better performance.

This invention was made to eliminate the above-mentioned drawbacks of the conventional products, and an object of the present invention is to provide a contact material for a vacuum breaker that has excellent large current interrupting performance and good withstand voltage performance.

The inventors prototyped a contact material by adding various metals, alloys, and intermetallic compounds to Ou, incorporated it into a vacuum switch tube, and conducted various experiments. So far, Ou, Or,
The breaking performance of the material composed of Ta is higher than that of conventional products (
We have found that it is extremely superior to Ou-25wt%Or alloy), but in order to obtain a breaking capacity 1.5 times that of the conventional product, it is necessary to add 5 to 25% Ta by weight. % had to be added.

Therefore, various experiments were conducted in order to effectively improve the blocking performance by reducing the amount of Ta, which is generally an expensive material, added as much as possible. As a result, Cu, (!r
, when Ta is the main component and a small amount of T1 is added, T
It was found that even if the amount of Ta was reduced, the blocking performance was very good and the withstand voltage performance was good.Furthermore, by adding a small amount of T1, the blocking performance was significantly improved within a certain range of Ta amount compared to when no T1 was added. It was also found that performance improved.

The contact material for a vacuum breaker of the present invention contains O gold and 10 to 35% by weight of Or as other components, and T.
It is characterized by containing a in a range of 20% by weight or less and T1 in a range of 5% by weight or less.

Hereinafter, one embodiment of the present invention will be explained with reference to the drawings. Figure 1 is a structural diagram of a vacuum switch tube.
) and an end plate (2) that closes both ends of this vacuum insulated container (1).
) and (3).
) and (5) are electrode rods (6) and (7), respectively.
are placed facing each other at one end. 117) is integrally joined to the end plate (3) via a bellows (8) so as to be able to move in the axial direction without compromising airtightness. The shields (9) and 00 respectively cover the inner surface of the vacuum insulating container (1) and the bellows (8) so that they are not contaminated by vapor generated by the arc. As shown in FIG. 2, the electrode (5) is brazed to the electrode rod (7) with a brazing material (51) interposed on its back surface. The electrodes (4) and (5) are Cu-
It is made of 0r-Ta-Ti type contact material.

Figure 3 shows the relationship between the amount of T1 added to the alloy and the amount of T1 added to the alloy with the amount of Cr in the alloy fixed at 25% by weight and the amount of 'ra fixed at O, l, 5, 10, 45, 20.25 weight 96. This shows the relationship. The vertical axis of the figure is the conventional product (Cu-2
50r product) is shown as the ratio when the breaking capacity is 1,
The horizontal axis indicates the amount of T1 added. In the figure (A) is the conventional product (Ou
-250r product). As can be seen from the figure, for each Ta amount, the breaking capacity peaks when the added amount of Ti is 0.5% by weight, and the breaking performance is improved by adding Ti, but when Ta t is 20%, the breaking capacity peaks. weight%
If the temperature exceeds that level, the effect of T1 disappears, and rather the breaking performance deteriorates. In addition, the effect of T1 addition is more effective as the amount of Ta is smaller (V), and when the amount of Ta is 1% by weight, T
When 0.5% by weight of 1 is added, the breaking capacity is 15 times that of the conventional product (0u-25% by weight Cr product). Further, when the Ta amount is 10% by weight, by adding 0.5% by weight of Ta, a breaking capacity 1.9 times or more than that of the conventional product can be obtained. In other words, when the amount of Ta is relatively small, alloys and compounds formed by moderate reaction of Ti with other elements are uniformly and finely dispersed, significantly improving the breaking performance, and furthermore, Cu
Since there is sufficient heat resistance, there is no reduction in electrical conductivity or thermal conductivity, so that the heat input by the arc can be quickly dissipated. However, as the amount of Ta increases, the amount of Cu inevitably decreases, so the Ou,! :Although the compound formed by the reaction of Ti itself has elements that improve the breaking performance, it has a greater negative effect of reducing electrical conductivity and thermal conductivity, and the breaking performance caused by the reaction between Ti and other elements has a greater negative effect. This seems to be because the improvement factors are canceled out and the total breaking performance is not improved. Furthermore, if the amount of Ta is the same, if the amount of T1 exceeds an appropriate amount that is effective, the electrical conductivity and thermal conductivity will decrease significantly, which is not desirable. Furthermore, for each amount of Ta, it is most preferable to add 0.5% by weight of T1 in terms of blocking performance. In addition, 0u-Or -Ta-Ti used in this experiment
The alloy is obtained by molding and sintering a mixed powder containing Ou, Or, Ta, and Ta powders in required amounts.

Figure 4 shows the amount of added Ta when the amount of Cr in the alloy is fixed at 25% by weight and the amount of Ti is fixed at 0.0.5.1.0.1.5.3.5% by weight. The graph shows the relationship between the amount and the breaking capacity, and the vertical axis of the figure is for the conventional product (Ou-25
The ratio is shown when the breaking capacity of 0r product) is set to 1, and the horizontal axis shows the amount of Ta added. As shown in Figure 4, T
When the amount of i is 0.5% by weight, the effect of increasing the breaking capacity due to the addition of T1 is observed when the amount of Ta is 20% by weight or less. On the other hand, when the amount of T1 added is very small (approximately 5% by weight of C1), it is effective in the range of 5% by weight or less;
If it exceeds 3% by weight, contact resistance tends to increase, and depending on the usage conditions, 3% by weight or less is desirable. Furthermore, when the Ti amount is 1.0% by weight, the effect is seen when the Ta amount is 5%.
When the amount of Ti is 1.5% by weight, the effect is observed when the amount of Ta is 3% by weight or less. On the other hand, when the amount of T1 exceeds 2% by weight, there is an effect in terms of breaking performance only when the amount of Ta is about 1% by weight. On the other hand, when the Ti content is 0.5% by weight or less, there is an effect of improving the breaking performance over the widest range of the Ta content, that is, the range of 20% by weight or less.

From the above results, G! A ternary alloy of u-cr-Ta? (On the other hand, in order to further improve the breaking performance of the ternary alloy by adding T1, T1 should be 0.8% by weight or less, T
The amount of a is preferably in the range of 3.5 to 18% by weight. moreover,
In order to obtain excellent breaking performance by reducing the amount of Ta added as much as possible, it is desirable that the 'ra amount be in a range of 15% by weight or less.

The inventors conducted experiments as shown in FIGS. 3 and 4 while varying the amount of Cr.
An improvement in the breaking performance was observed by adding T1 in the range of 10% by weight, but there was no change even if T1 was added in the range where the amount of Cr was less than 10% by weight, and conversely, when the amount of Cr exceeded 35% by weight, the breaking performance improved. A decrease also occurs.

On the other hand, in Ou-Or -Ta-Ti alloy, Or is 10~
35% by weight, Ta less than 20 heavy bones, T1 5% by weight 96
Contact materials containing the following range are conventional products (Ca-25ar
Although not shown in the figure, it has been confirmed through various experiments that the contact resistance is not inferior and the withstand voltage performance is equally good as compared to the product (product).

Although not shown, Bi, Te, and Sb are added to the above alloy.
.

TI! , Pb, Se, Oθ and Oa, an alloy thereof, an intermetallic compound thereof, and an oxide thereof at 20% by weight.
Even in the contacts for low-segment vacuum breaker with the following additives,
It has been confirmed that it has the effect of increasing the blocking property as in the above embodiment.

Note that when 20% by weight or more of at least one of a low melting point metal, its alloy, its intermetallic compound, and its oxide was added, the breaking performance was significantly reduced. Further, when the low melting point metal is Cθ or Oa, the properties are slightly inferior.

In addition, in the above-mentioned example, this invention was applied to Cu-0r-Ta-
Although the explanation has been made using a Ti alloy, each element of the above alloy is a simple substance,
The purpose of the period is also reached when the per capulars, three or king's alloys, enclosures, king or king interconnections or those complexes are distributed as a complex.

As described above, the present invention is characterized in that it contains copper and other components such as chromium in a range of 10 to 35% by weight, tantalum in a range of 20% by weight or less, and titanium in a range of 5% by weight or less. Therefore, even if the amount of Ta is reduced, it is possible to obtain a contact material for a vacuum breaker that has excellent breaking performance and good withstand voltage performance.

Furthermore, 3.5 to 18% by weight of tantalum and 0.0% by weight of titanium.
When the content is limited to 8% by weight or less, the breaking performance is improved compared to the case where titanium is not added.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view showing the structure of a typical vacuum switch tube.
Fig. 2 is an enlarged cross-sectional view of the ti portion in Fig. 1, and Fig. 3 shows that the amount of Or in the contact material of the embodiment of this invention is fixed in a 25-layer lance shape, and the amount of Ta is 0.1.5゜10. , 15.20.
Figure 4 is a characteristic diagram showing the change in breaking capacity when the amount of T1 added is changed for an alloy fixed in a 25-layer lance shape. , Ti amount 0.0.5゜1.0.1.5.3.5
It is a characteristic diagram showing the change in the breaking capacity when the amount of Ta is changed for an alloy whose heavy failure percentage is fixed. In the figure, (1) is a vacuum insulated container, (21, (3) is an end plate, (4), f5) is an electrode, f6>, (7) is an electrode rod, (8) is a bellows, (9), 01 is the shield, (51) is the brazing material, (A) is the conventional product (Ou-250r
This is the breaking capacity of the product. Agent Masuo Oiwa Figure 1 Figure 2 Figure 3 0 0.5 1.0 1.5 Ti Homare Tokaro 1E (aperture =/-) Figure 4 0 10 20 30 40 Ta t (
11° East)

Claims (1)

[Claims] rl) It is characterized by containing copper and, as other components, chromium in a range of 10 to 35% by weight, tantalum in a range of 20% by weight or less, and titanium in a range of 5% by weight or less. Contact material for vacuum breaker. (2) The contact material for a vacuum breaker according to claim 1, characterized in that titanium is contained in a range of 3% by weight or less. (3) The contact material for a vacuum breaker according to claim 1, which contains titanium in a range of 0.8% by weight or less. (4) Tantalum: 3.5-18% by weight, titanium: 0
．． The contact material for a vacuum breaker according to claim 1, characterized in that the contact material is contained in a range of 8% by weight or less. (5) Tantalum: 3.5-15% by weight, titanium: 0
．． A contact material for a vacuum breaker according to clause 1 of the patent claim, characterized in that the content is in a range of 8% by weight or less. (6) Bismuth, tellurium, antimony, thallium. At least one low melting point metal such as lead, selenium, cerium, and calcium, its alloy, its intermetallic compound, and its oxide at 20% by weight 96I
, 1. A contact material for a vacuum breaker according to any one of claims 1 to 5, characterized in that the contact material contains: