JPH113624A - Encapsulated contact material and encapsulated contact using said material for electrodes - Google Patents

Abstract

[PROBLEMS] To provide an inexpensive encapsulated contact material having a long contact life even under high load conditions. SOLUTION: A coating layer having a thickness of 0.1 μm or more is formed on a contact substrate, and the coating layer is formed of Cr, Mn, Fe, Co,
0.5 to 50 at% of at least one element of Ni, and 0.5 to 50 at% of at least one element of C or Si
An encapsulated contact material containing 50 at%, containing 0 to 40 at% of O (oxygen), and a balance of 59 at% or more of Cu or Ag. [Effect] Since it contains an arc damage dispersing element such as Cr, Mn, Fe, Co, and Ni, and contains a melting element of C or Si, a good contact life can be obtained even under a high load condition in which arc discharge occurs. Also, since expensive Rh and Ru are not used, the cost is low.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an encapsulated lead switch for opening and closing in a non-oxidizing atmosphere, suitable for electrodes of relays, etc., which can be operated stably for a long period of time and is inexpensive. It relates to an encapsulated contact material.

[0002]

2. Description of the Related Art A sealed contact has a structure in which a sealed contact material is mounted as an electrode in a glass or plastic sealed container in a non-oxidizing atmosphere. Conventionally, the encapsulated contact material includes Ag, A on a Ni—Fe alloy base material.
forming a plating layer of u, Cu, etc., on which Rh or R having a high melting point and excellent electrical conductivity, hardness, and wear resistance;
Materials coated with a layer of u are often used. Ag, A
The plating layer of u, Cu, etc. prevents the diffusion of Rh or Ru of the coating layer to the base material by the Joule heat during the opening / closing operation of the contact, and the adhesion between the Rh or Ru coating layer and the contact base material. Also acts to improve the performance.

[0003]

However, the above-mentioned encapsulated contact material has a disadvantage that the cost is high because expensive Rh or Ru is used. Therefore, an encapsulated contact material in which a Cu-Ni diffusion layer is formed on a Ni-Fe alloy base material has been proposed. However, this material has a disadvantage in terms of cost because it needs to be coated with Rh or Ru, since switching failure occurs between the contacts under high load conditions where arc discharge occurs.

[0004] In view of the above, the present inventors have conducted intensive research on an encapsulated contact material which can be sufficiently applied even under a high load condition, and have found that the base metal (Cu or the like) of the coating layer contains Cr, M, or the like.
Addition of n, Fe, Co, Ni, etc. disperses the damage caused by the arc, and addition of C, Si, etc. suppresses the transfer of wear and tear of the base metal, thereby significantly improving the opening / closing operation of the encapsulated contact. The present inventors have found and conducted further research to complete the present invention. An object of the present invention is to provide an inexpensive encapsulated contact material in which switching operation is performed stably for a long period even under high load conditions, and an encapsulated contact using the encapsulated contact material for an electrode.

[0005]

According to the first aspect of the present invention,
A coating layer having a thickness of 0.1 μm or more is formed on the contact substrate,
The coating layer includes at least 59 at% of at least one element of Cu or Ag, 0.5 to 40 at% of at least one element of Cr, Mn, Fe, Co, and Ni, and C or S.
0.5 to 30 at% of at least one element of i
An encapsulated contact material containing (oxygen) in an amount of 0 to 20 at%, with the balance being unavoidable impurities.

According to a second aspect of the present invention, there is provided the encapsulated contact material according to the first aspect, wherein a concentration variation of each alloy element in a thickness direction of the coating layer is ± 5 at% or less.

According to a third aspect of the present invention, the coating layer is composed of two or more layers having different compositions, each layer containing at least one element of Cu or Ag in an amount of at least 59 at%, Cr, Mn, and F.
e, at least one element of Co, Ni is 0 to 40 at.
%, At least one element of C or Si is 0 to 30
2. The encapsulated contact material according to claim 1, wherein the encapsulated contact material contains at% and O (oxygen) in an amount of 0 to 20 at%, with the balance being unavoidable impurities.

The invention according to claim 4 is that the coating layer contains Cr,
4. The encapsulation according to claim 1, wherein at least one of Mn, Fe, Co, and Ni is contained with a concentration gradient in a thickness direction of the coating layer. It is a contact material.

According to a fifth aspect of the present invention, the coating layer contains at least one of C and Si with a concentration gradient in the thickness direction of the coating layer. The encapsulated contact material according to any one of 2, 3, and 4.

[0010] The invention according to claim 6 is based on claims 1 and 2,
An encapsulated contact characterized in that the encapsulated contact material according to any one of 3, 4, and 5 is used for an electrode.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a contact base material includes:
Any metal material having strength and conductivity is used. For example, Fe, Ni, Co, Ni-Fe alloy, Co-F
e-Nb-based alloy, Co-Fe-V-based alloy, Fe-Ni-
Al-Ti alloy, Fe-Co-Ni alloy, carbon steel,
Phosphor bronze, nickel silver, brass, stainless steel, Cu-Ni-S
An n-based alloy, a Cu-Ti-based alloy, or the like is used. In the present invention, if a base layer such as Ni is provided on the contact base material,
Diffusion of the contact base material into the coating layer is suppressed, and good contact characteristics can be stably obtained for a longer period.

In the present invention, Cu or Ag constituting the coating layer is an inexpensive metal element serving as the base of the coating layer.
The coating layer is provided with conductivity. The reason for specifying the content to be at least 59 at% is that if it is less than 59 at%, sufficient conductivity required for the coating layer cannot be obtained.

[0013] Cr, Mn, Fe, Co, and Ni disperse the arc discharge generated during use over the entire contact surface, thereby improving operation failure due to shape damage of the contact surface. The reason why the content is specified in the range of 0.5 to 40 at% is that if the content is less than 0.5 at%, the effect cannot be sufficiently obtained, and if it exceeds 40 at%, the melting point is lowered and the contact is greatly consumed. . Hereinafter, the various elements such as Cr are referred to as arc damage dispersing elements.

C or Si is a high melting point element and has an effect of suppressing consumption of the base metal (Cu, Ag) and transfer to the counter electrode. The reason for defining the content to be 0.5 to 30 at% is that if the content is less than 0.5 at%, the effect cannot be sufficiently obtained.
If the content exceeds 30 at%, the coating layer becomes brittle, and the surface is easily peeled off in the form of a film. Hereinafter, C or Si is referred to as a melting-resistant element. An appropriate amount of O (oxygen) increases the melting point and hardness of the coating layer to improve wear resistance. Its content is 0
The reason why the content is specified at 20 at% is that if the content exceeds 20 at%, the coating layer becomes porous, becomes brittle, and the contact life is shortened. In the present invention, the composition of the entire coating layer is defined by claim 1.
Defined in the range described. In the present invention, the reason why the thickness of the coating layer is specified to be 0.1 μm or more is that if the thickness is less than 0.1 μm, a sufficient contact life cannot be obtained.

According to a second aspect of the present invention, the variation in the concentration of each element in the coating layer in the thickness direction is suppressed to a low level, that is, the coating layer is homogenized to reduce the variation over time of the contact characteristics. . When the concentration variation is ± 5at% or less,
In particular, the effect is remarkable.

According to a third aspect of the present invention, the coating layer is composed of two or more layers having different compositions. By forming two or more layers in this manner, for example, the contact base material side and the contact surface side can be separated. Thus, the composition can be appropriately selected, and the life of the switching operation can be efficiently improved.

According to a fourth aspect of the present invention, there is provided an encapsulated contact material in which the arc damage dispersing element has a concentration gradient in the thickness direction of the coating layer. For example, the concentration of the arc damage dispersing element increases on the surface side. In the case of such a gradient, the effect can be obtained with a small amount of the arc damage dispersing element. In the case where the concentration of the arc damage dispersing element is reduced so that it is lower on the surface side, the arc damage dispersing element gradually diffuses to the surface of the coating layer during use, and a required amount of the arc damage dispersing element is removed from the coating layer. Long-lasting on the surface.

According to a fifth aspect of the present invention, there is provided an encapsulated contact material in which the melting resistant element has a concentration gradient in the thickness direction of the coating layer, for example, such that the concentration of the melting resistant element increases on the surface side. The graded one can prevent arc damage between contacts with a small amount of melting resistant element. In the case where the concentration of the anti-fusing element is graded such that the concentration of the anti-fusing element becomes lower on the surface side, the anti-fusing element gradually diffuses to the surface of the coating layer during use, and the required amount of the anti-fusing element spreads over the surface of the coating layer for a long time. Is held for By imparting a concentration gradient to both the arc damage dispersing element and the melting resistance element, the effect is further improved. In the present invention, a vapor phase growth method such as a sputtering method is convenient for forming the coating layer because the concentration distribution of the composition can be easily controlled.

The invention according to claim 6 is the invention according to claims 1, 2,
An encapsulated contact using the encapsulated contact material according to any one of 3, 4, and 5 as an electrode, the electrode (contact material) is less damaged by an arc, and the transfer of wear of the base metal is suppressed, so that the opening / closing operation is jumped. It is an encapsulated contact material that has been improved.

[0020]

The present invention will be described below in detail with reference to examples. (Example 1) Ni-48 at% Fe alloy plate (1 x 1 x 0.2 m
m) was used as a contact base material, and a coating layer having the composition specified in the present invention was formed thereon to prepare an encapsulated contact material. First, the surface of the contact substrate was ultrasonically cleaned with acetone for 5 minutes, and further cleaned by electrolytic polishing using phosphoric acid. Next, this contact base material is set in a vacuum chamber, and the inside of the chamber is 2 × 1
After evacuating to 0 ^-4 Pa or less, the vacuum pump valve was half-opened, and Ar gas was introduced while reducing the exhaust conductance to stabilize the inside of the chamber at 1 × 10 ^-1 Pa. Next, a voltage of -400 V was applied to the contact base material, a high-frequency power of 0.2 kW was generated from a high-frequency antenna in the chamber, and ion bombardment treatment was performed with Ar ions to clean the surface of the contact base material. Next, the inside of the chamber was set to an atmosphere of Ar or Ar + O ₂ gas of 0.66 Pa,
A single coating layer was formed on the surface of the contact substrate held at 400 ° C. The coating layer was formed by an RF magnetron sputtering method. The target is at least one of each of a base metal element, a melting resistance element, and an arc damage dispersing element.
Elements were used. The amount of O was controlled by changing the oxygen partial pressure in the atmosphere. The deposition rate was varied.

Comparative Example 1 An encapsulated contact material was produced in the same manner as in Example 1, except that the composition of the coating layer was outside the specified range of the present invention.

Using the thus obtained sealed contact materials as electrodes, N ₂ gas-filled reed switches were produced, and the contact life of these reed switches was tested at room temperature. Contact life is high when an arc discharge occurs between electrodes
The switching operation was repeated under a driving magnetic field of 40 Ampere Turn under (100 V-0.5 A-10 Hz), and the number of operations (contact life) until the opening / closing failure occurred was expressed. The number of test pieces was 10 each. The results are shown in Tables 1 and 2.

[0023]

[Table 1]

[0024]

[Table 2]

As is clear from Table 1, the sample of the present invention was No. 1
Nos. 15 to 15 have a long contact life and are very stable. On the other hand, in the comparative example products shown in Table 2,
Nos. 4 and 6 contain no damage dispersing element because no melting resistant element is contained, and Nos. 9 and 10 are coating layers because No. 7 and 8 have a large amount of melting resistant element C. Is thin,
In each case, the average life was reduced.

Example 2 An encapsulated contact material was produced in the same manner as in Example 1 except that the coating layer was composed of two or more layers having different compositions. The deposition conditions were changed for each layer.

Comparative Example 2 An encapsulated contact material was produced in the same manner as in Example 2 except that the composition of the coating layer was outside the range specified in the present invention.

Using the thus-obtained sealed contact materials for electrodes, N ₂ gas-filled reed switches were produced, and the contact life of these reed switches was tested in the same manner as in Example 1. Tables 3 and 4 show the number of operations (contact life) until a switching failure occurs.

[0029]

[Table 3]

[0030]

[Table 4]

As is evident from Table 3, N of the sample of the present invention was
o.16 to 22 have a long contact life and have one coating layer.
The contact life is longer than that of the first embodiment formed in the layer. This is because the effect of each of the constituent elements was better exhibited by forming the coating layer in two layers.
On the other hand, in the comparative example products of Table 4, No. 11 does not contain the melting-resistant element, and No. 12 does not contain the damage-dispersing element. No. 14 and 17 are thin because they do not contain both elements.
In Nos. 15 and 16, the contact life was extremely short and the life variability was large because of the high resistance to melting elements.

Example 3 An encapsulated contact material was produced in the same manner as in Example 1, except that the composition of the coating layer was inclined in the thickness direction. In forming the coating layer, the input power of the target of each element was continuously changed.

Using the thus-obtained sealed contact materials for electrodes, N ₂ gas-filled reed switches were manufactured, and the contact life of these reed switches was tested in the same manner as in Example 1. Table 5 shows the number of operations (contact life) until the opening and closing failure occurs.

[0034]

[Table 5]

As is apparent from Table 5, the N of the sample of the present invention was
o.23 to 29 have a long contact life, and
2 is longer than the contact life. This is because the effect of each of the constituent elements was extremely efficiently exhibited by inclining the composition in the thickness direction of the coating layer.

Although the case where the coating layer is formed on the substrate having the contact size has been described above, the present invention is also applicable to forming the coating layer on a large substrate and sizing the coating layer to the size of the contact to obtain an encapsulated contact material. The same effect can be obtained.

The encapsulated contact material of the present invention is an encapsulated relay,
It can be used in various fields such as encapsulated switches. Also, in an environment where Cu or Ag of the base metal does not react with the sulfide in the atmosphere to degrade the contact characteristics, it can be widely applied to ordinary switches used in the atmosphere.

[0038]

As described above, the encapsulated contact material of the present invention comprises at least one of Cr, Mn, Fe, Co and Ni.
The arc damage is dispersed due to the inclusion of elements, and C or S
i, the base metal (Cu, A
The transfer of wear of g) is suppressed, and by further containing O, the wear resistance is further improved, and a good contact life can be obtained even under a high load condition. Also, since expensive Rh and Ru are not used, the cost is low. An encapsulated contact using the encapsulated contact material for an electrode is inexpensive and has a long contact life. Therefore, there is an industrially significant effect.

Claims (6)

[Claims] 1. A coating layer having a thickness of 0.1 μm or more is formed on a contact base material, said coating layer containing at least one element of Cu or Ag in an amount of at least 59 at%, Cr, Mn, Fe,
At least one element of Co and Ni is 0.5 to 40 at.
%, At least one element of C or Si is 0.5 to
An encapsulated contact material comprising 30 at%, O (oxygen) in an amount of 0 to 20 at%, and the balance consisting of unavoidable impurities. 2. The encapsulated contact material according to claim 1, wherein a concentration variation of each alloy element in a thickness direction of the coating layer is ± 5 at% or less. 3. The coating layer comprises at least two layers having different compositions, each layer comprising at least 59 at% of at least one element of Cu or Ag and at least one element of Cr, Mn, Fe, Co and Ni. 0 to 40 at%, at least one element of C or Si is 0 to 30 at%, and O (oxygen) is 0
2. The encapsulated contact material according to claim 1, wherein the content of the contact material is in the range of about 20 at% to about 20 at%, with the balance being inevitable impurities. 4. A coating layer comprising Cr, Mn, Fe, Co, N
2. The method according to claim 1, wherein at least one element of i is contained with a concentration gradient in a thickness direction of the coating layer.
4. The encapsulated contact material according to any one of items 2 and 3. 5. The coating layer according to claim 1, wherein at least one of C and Si is contained with a concentration gradient in a thickness direction of the coating layer. The encapsulated contact material according to any one of the above. 6. An encapsulated contact, characterized in that the encapsulated contact material according to any one of claims 1, 2, 3, 4, and 5 is used for an electrode.