JPH0563534B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] This invention is applicable to electrical equipment used in slip springs that rotate and slide relative to each other in ultra-high vacuum such as artificial satellites, space equipment, vacuum equipment, etc. to transmit power, electrical signals, etc. This invention relates to a silver-based composite brush material. [Prior art] The characteristics required of slip springs are firstly to reliably transmit power and electrical signals, and secondly
It is to operate stably for a long time. In order to satisfy the first characteristic, the contact resistance and electrical noise between the brush material and the ring material must be small.The second characteristic is that the frictional resistance must be low and stable, and the wear of the brush material and the ring material must be low. It needs to be small. To meet these demands, metal-graphite brush materials have traditionally been developed, which are made by adding metal powder (silver, copper, etc., hereinafter referred to as Ag or Cu) to increase conductivity, such as carbon or graphite, which have excellent conductivity and lubricity. has been provided. These brush materials maintain the lubricating properties of the graphite they contain under normal usage conditions, but at high temperatures (150
℃ or higher), low humidity (2g/ ^m3 or lower), vacuum (10 ^-2 torr
It is known that dust wear occurs due to a lack of adsorbed moisture in conditions such as (below), and as a countermeasure to this problem, it has been proposed to add a solid lubricant with a layered structure similar to graphite. For example, in Japanese Patent Publication No. 36-914, molybdenum disulfide (hereinafter referred to as MoS ₂ ) powder is added and sintered to a mixed powder of metal and graphite, and in Japanese Patent Publication No. 58-51483,
MoS ₂ , tungsten disulfide (hereinafter referred to as WS ₂ )
Proposals have been made for metal-graphite brush materials containing one of these and boron nitride. Furthermore, as an application example of other solid lubricants,
Cu typified by those shown in Publication No. 58910
Composite brush materials have been announced that are made by mixing MoS ₂ alloy powder and MoS 2 powder, hot pressing in the air, or molding and sintering. However, ultra-high vacuum (10 ^-2 torr
Brush materials that have the ability to transmit power and electrical signals (below) have rarely been announced in Japan. On the other hand, overseas, especially in the United States, slip springs are used in ultra-high vacuum during the development process of artificial satellites, spacecraft, space equipment, etc. associated with space development.
Research is being carried out mainly at NASA research institutes, in the surrounding aircraft industry, and by manufacturers of artificial satellites and their parts, and some evaluation test results have also been published. Currently, space equipment mounted on communication satellites, broadcasting satellites, weather satellites, etc. uses slip springs that can transmit power and electrical signals in ultra-high vacuum for long periods of time ranging from several years to 10 years without maintenance. is needed. As a brush material that satisfies these requirements, a composite material has been announced in which silver powder with the highest conductivity is used as a matrix, a solid lubricant with excellent lubricity is mixed and added to this in a vacuum, and the mixture is formed and sintered. There is. For example, LMSC
(Lockeed Missiles & Company)
The sliding _properties (amount of wear, contact resistance, electrical noise), etc. However, simply adding tin to a solid lubricant does not necessarily improve the sliding properties, and even in Ag-solid lubricant composite sintered materials, the amount of solid lubricant added, the method of addition, and the manufacturing method of the composite sintered material, etc. Its characteristics vary significantly depending on the type of material. For example, J.
Regarding the sliding properties of Ag-MoS ₂ composite brush material prepared by hot pressing with mixed addition of MoS ₂ in the range of 5 to 15% by weight, C. Anderson reported that the wear of the brush material decreased as the amount of MoS ₂ increased. reported that the electrical noise increases as the amount of MoS ₂ increases. On the other hand, Ag-
Regarding MoS ₂ composite brush materials, it is also stated that the higher the amount of MoS ₂ , the lower the electrical noise, but the higher the wear. Therefore, it can be seen that the sliding properties of the Ag-solid lubricant composite sintered material are largely related to the amount of solid lubricant added, the method of addition, and the method of manufacturing the composite sintered material. [Problems to be solved by the invention] As a conventional example, based on conventional technology, a composite sintered brush material made by adding MoS ₂ powder to Ag powder was made into MoS ₂ 5
Prototypes were made in the range of ~25% by weight. Nos. 15 to 19 in the table show the properties such as compounding ratio, density, and density ratio of the prototype composite sintered brush materials. The sliding properties of the composite brush material made by adding MoS ₂ powder to this Ag powder were evaluated using a pin/disk type friction tester and a slip ring model machine. 1st
In each of curves 1 of A, B, and C in the figure, MoS ₂ is added to Ag powder.
Changes in contact resistance (mΩ), electrical noise (mV), and specific wear amount (mm ² /mm・N) with respect to the current density (A/cm ² ) of the composite brush material when 15% by weight of powder was added. show. According to the results, contact resistance, electrical noise, and specific wear of the brush material in a low current flow region with a current density of about 10 (A/cm ² ) were all small and generally good. In addition, the coefficient of friction is low, and an adhesion layer of MoS ₂ is formed on the sliding surface of the mating material (Ag or Ag-Cu), and good lubrication is maintained between this transfer layer and the brush material. It is thought that the However, as the amount of current applied to the contact resistance increases, it gradually increases, and at a current density of 83 (A/cm ² ), it shows a large value, which is not preferable. It is thought that the increase in the aperture resistance due to the increase in the amount of current has an adverse effect. Moreover, because the current is transmitted through a transferred film of MoS ₂ (specific resistance: 851 Ωcm), which has a high specific resistance, it is thought that the aperture resistance increases significantly, depending on the condition of the sliding surface. Electrical noise also increases as the amount of current increases, and at a current density of 83 (A/cm ² ), a current density of 10
(A/cm ² ) compared to when the current is applied. The specific wear amount of the brush material also increases as the amount of current applied increases, which is not preferable. The increase in specific wear amount is
This is thought to be because contact resistance and electrical noise increased due to the increased amount of current, which increased electrical wear. In addition, when we investigated the relationship between the amount of current applied, changes in contact resistance, changes in electrical noise, and changes in the specific wear amount of the brush material for a composite brush material made by adding MoS ₂ powder to Ag powder in a range of 5 to 25% by weight, we found that the above results were obtained. It showed the same tendency as the composite brush material with 15% by weight of MoS ₂ powder added to Ag powder shown in . From the above, in the composite brush material made by adding MoS ₂ powder to Ag powder in the range of 5 to 25% by weight, the contact resistance, electrical noise, specific wear amount of the brush material, and friction coefficient are all small and good when low current is applied. However, as the amount of current is increased, the specific resistance of MoS ₂ is large, so the aperture resistance increases significantly, contact resistance and electrical noise increase, and electrical wear increases. That is,
Ag-based composite brush materials made by adding a solid lubricant of MoS ₂ powder to Ag powder only have a high resistance in a wide current carrying range from low current to large current, due to the high specific resistance of MoS ₂ . , contact resistance,
It was not possible to simultaneously satisfy the sliding characteristics of electrical noise, wear characteristics, and friction characteristics. This invention was made to solve these problems, and has good friction and wear characteristics in a wide range of current flow ranges from low current to large current, as well as excellent conductivity, reducing contact resistance and electrical noise. The purpose of the present invention is to efficiently obtain a composite brush material for electrical machinery with a small amount of carbon. [Means for Solving the Problems] The composite brush material for electrical machinery of the present invention contains at least one of molybdenum disulfide and tungsten disulfide and niobium selenide, with the balance being silver. Specific examples include the formula: Ag _(100-ab) −(M) _a −(NbSe ₂ ) _b {In the formula, M is at least one of molybdenum disulfide (MoS ₂ ) and tungsten disulfide (WS ₂ ). , where Ag is silver and NbSe ₂ is niobium selenide. a, b are weight concentrations, 4≦a≦24, 1≦b
Represents a number that satisfies the relationships of ≦10 and 5≦a+b≦25. } This is a composite brush material for electrical machinery. [Function] At least one of molybdenum disulfide and tungsten disulfide in the present invention is added to reduce the friction coefficient and specific wear amount and maintain a good lubrication state. Niobium selenide has a specific resistance of 5.35×10 ^-4 Ωcm, which is significantly smaller than molybdenum disulfide and tungsten disulfide, and has a layered structure similar to molybdenum disulfide, so it is mainly used for applications ranging from low current to large current. It is added to reduce contact resistance and electrical noise over a wide current-carrying area. Furthermore, by adding at least one of molybdenum disulfide and tungsten disulfide together with niobium selenide, electrical wear is reduced, the composite brush material is sufficiently bonded, mechanical strength is increased, and durability is increased. It is added to improve wear resistance.
In addition, by using a, b, and a+b as described in the claims above, the above characteristics are good over a wide range of energization range,
A composite brush material with good properties can be obtained efficiently. [Example] Molybdenum disulfide (MoS ₂ ) according to this invention
The amount of at least one of tungsten disulfide (WS ₂ ) added is preferably 4 to 24% by weight.
If it is less than 4% by weight, the friction properties and wear resistance will deteriorate;
If it exceeds 24% by weight, contact resistance and electrical noise will increase, especially in the region where large currents are applied.
The particle size of these solid lubricants is not particularly limited, but in order to obtain a uniform dispersion state, it is desirable to use particles with an average particle size of 30 μm or less, preferably 1 to 20 μm. The amount of niobium selenide (NbSe ₂ ) added is 1 to 10
Weight percent is preferred. If it is less than 1% by weight, there will not be much effect in reducing contact resistance, electrical noise, or specific wear amount, and if it exceeds 10% by weight, the contact resistance in the high current carrying region and the total current carrying amount will decrease, depending on the addition ratio with MoS ₂ . The electrical noise and specific wear amount in this area will increase. The particle size should be as small as possible, but it is important to handle the powder during blending and mixing, and to efficiently disperse NbSe ₂ , which has low resistivity, around MoS ₂ and WS ₂ to achieve the desired goal. Considering this, it is desirable that the average particle size is 0.5 to 5 μm. Note that the total amount of at least one of MoS ₂ and WS ₂ and NbSe ₂ added is preferably 5 to 25% by weight. If it is less than 5% by weight, the friction characteristics, wear characteristics, and electrical noise characteristics will deteriorate, and if it exceeds 25% by weight, the contact resistance and electrical noise will increase in the region where large current is applied, and the wear resistance will also deteriorate. In addition, in order to manufacture a composite brush material for electrical machinery using the above materials, known methods such as a method of mixing raw material powder and sintering after molding, or a method of sintering using a hot press, etc. can be used, but the sintering atmosphere is In order to prevent oxidative decomposition of the raw material powder, it is desirable to use an inert atmosphere or a vacuum atmosphere. The present invention will be specifically explained below with reference to Examples, but the present invention is not limited thereto. In addition, Nos. 1 to 14 of the table show examples of the present invention, and Nos. 20 to 26 of the table show properties such as compounding ratio, density, density ratio, etc. of the prototype composite sintered brush materials for comparative examples. show. Example 1 MoS ₂ powder with an average particle size of 10 μm and an average particle size of 3 μm
MoS ₂ powder was wet-mixed in an appropriate ratio, and then various mixed powders were mixed with Ag powder having an average particle size of 5 μm at a weight ratio of 1 to 25% by the same wet method. After drying these mixed powders, they were put into an electrographite carbon mold and a composite sintered brush material was prototyped using a vacuum hot press method. After the hot press is evacuated (10 ^-5 torr level),
350Kg/cm ² after heating and holding at 800℃ for about 15 minutes
The test was carried out by applying pressure to 100% and keeping it in that state for about 45 minutes. Thereafter, the material was cooled in a furnace, the pressure was released at 500°C, and the material was further cooled in a vacuum in a furnace to room temperature to obtain a composite brush material. The table shows the characteristics of some of these prototypes, such as the blending ratio, density, and density ratio. These composite brush materials were processed into a rectangular parallelepiped of 2 mm x 6 mm x 3 mm, pure Ag and Ag-Cu rings were selected as the mating materials, and they were tested in high vacuum (10 ^-7 torr level) using a slip ring model testing device. Contact load at
1N, sliding speed 75mm/s, current density 0 to 83
A sliding test was conducted under the condition of (A/cm ² ). The contact area between the brush material and the ring material is 12 ^mm2 . Then, the sliding characteristics such as friction coefficient, specific wear amount, contact resistance, and electrical noise were investigated in vacuum and energized state. The results are shown in each of A, B, and C in Figure 1.
Contact resistance ( _mΩ ) change, electrical noise ( _mV ) change, and specific wear amount (mm ² / mm・N) Shows change. 1st
Curves 2 of A, B, and C in the figure are Ag-15% by weight MoS ₂
Contact resistance (mΩ) change with respect to current density of a composite brush material in which 1% by weight of MoS ₂ powder in the composite brush material is replaced with NbSe ₂ powder, that is, Ag-14% by weight MoS ₂ -1% by weight NbSe ₂ composite brush material , shows changes in electrical noise (mV) and changes in specific wear amount (mm ² /mm・N). Similarly, curve 3 of A, B, and C in Figure 1
is the contact _{resistance (} m
Ω) change, electrical noise (mV) change, and specific wear amount (mm ² /mm・N) change, and A, B, and C in Figure 1.
Curve 4 is Ag-5wt% _MoS2-10wt %
The graph shows changes in contact resistance (mΩ), electrical noise (mV), and specific wear amount (mm ² /mm・N) with respect to the current density of the NbSe ₂ composite brush material. The above results were obtained in the same manner as in the example.
Ag with MoS ₂ powder added alone to Ag powder - 15% by weight
Comparison with MoS ₂ composite brush material shows that the contact resistance decreases in the entire energization range even with the addition of 1% by weight of NbSe ₂ , as shown in curves 1, 2, 3, and 4 of A in Figure 1. are doing. but,
When 10% by weight of NbSe ₂ was substituted and added, although the contact resistance decreased significantly in the low current carrying region, the contact resistance tended to increase in the large current carrying region. Next, regarding electrical noise, as shown in curves 1, 2, 3, and 4 of B in Figure 1, composite brush materials containing 1% by weight of NbSe ₂ and 2.5% by weight of NbSe 2 do not contain MoS _2. Compared to the composite brush material added alone, the value is clearly smaller in the entire energization range. In addition, the composite brush material containing 10% by weight of NbSe ₂ has a slightly larger electrical noise in the low current range, but it has a smaller value in the high current range compared to the composite brush material containing MoS ₂ alone. It shows. Regarding the specific wear amount, as shown in curves 1, 2, 3, and 4 of C in Figure 1, NbSe ₂ was added at 1% by weight.
Composite brush materials with substitutional addition, 2.5% by weight substitutional addition, and 10% by weight substitutional addition are smaller in the entire current carrying region compared to composite brush materials with MoS ₂ added alone. In each of A, B, and C in Figure 2, the current density of the composite brush material is 83 (A/cm ² ) when a total of 15% by weight of MoS ₂ powder and NbSe ₂ powder is added to Ag powder.
Changes in contact resistance (mΩ), electrical noise (mV), and specific wear amount (mm ² /mm·N) are shown with respect to the replacement amount of NbSe ₂ powder and the amount of MoS ₂ powder added. As for the contact resistance, as shown in A in Fig. 2, the composite brush material for electrical machinery of the present invention in which MoS ₂ and NbSe ₂ are added together has an NbSe ₂ substitution amount of 1
In the range of ~15 wt%, it shows a clearly smaller value compared to the case of adding _MoS2 alone, but if it exceeds 10 wt%, an increase in contact resistance is unavoidable.
A displacement addition of 1 to 10% by weight is preferred. Regarding electrical noise, as shown in Fig. 2B, the composite brush material for electrical machinery of this invention containing MoS ₂ and NbSe ₂ combined has a NbSe ₂ substitution amount of 1 to 10.
There is a significant decrease in the weight percent range. If the amount of NbSe ₂ added exceeds 10% by weight, the amount of MoS ₂ added will decrease, resulting in poor friction properties and increased electrical noise. Regarding the specific wear amount, as shown in C in Figure 2, the composite brush material for electrical machinery of the present invention containing MoS ₂ and NbSe ₂ combined has a NbSe ₂ substitution amount of 1 to 10.
It has been reduced in the range of % by weight. If the NbSe ₂ substitution addition amount is less than 1% by weight, the effect of combined addition will not appear, and if the substitution addition amount exceeds 10% by weight, electrical noise will increase, electrical wear will increase, and the specific wear amount will increase, which is preferable. do not have. Example 2 Ag powder prototyped in the same manner as in Example 1 above
_Contact resistance ( _m
Ω) change, electrical noise (mV) change, and specific wear amount (mm ² /mm·N) change were evaluated in the same manner as in Example 1 above. A composite brush material in _{which a total of 5% by weight of MoS 2 powder and NbSe 2 powder was} added _to Ag powder was also used. As with the brush material, contact resistance, electrical noise, and specific wear amount increased as the amount of current applied increased, but when MoS ₂ powder was replaced with NbSe ₂ powder, contact resistance, electrical noise, and specific wear amount were reduced. In each of A, B, and C in Fig. 3, the current density of the composite brush material is 83 (A/cm ² ) when a total of 5% by weight of MoS ₂ powder and NbSe ₂ is added to Ag powder.
Changes in contact resistance (mΩ) and electrical noise (mV) with respect to the amount of NbSe ₂ powder added and the amount of MoS ₂ powder added
Changes in specific wear amount (mm ² /mm・N) are shown.
Regarding the contact resistance, as shown in A in Figure 3,
The composite brush material for electrical machinery of this invention in which MoS ₂ and NbSe ₂ are added together has a NbSe ₂ substitution addition amount of 1% by weight.
The above shows a smaller value compared to the case where MoS ₂ is added alone. Regarding electrical noise, as shown in Fig. 3B, the composite brush material for electrical machinery of the present invention in which MoS ₂ and NbSe ₂ are jointly added is superior to the case where MoS ₂ is added alone at a NbSe ₂ substitution amount of 1% by weight. It has decreased in comparison. However, when the amount of MoS ₂ added is less than 4% by weight, the frictional properties deteriorate and electrical noise increases. As for the specific wear amount, as shown in C in Fig. 3, the composite brush material for electrical machinery of the present invention in which MoS ₂ and NbSe ₂ are added together has a NbSe ₂ substitution amount of 1 to 4.
The amount is reduced compared to when MoS ₂ is added alone in the range of weight %, but when it exceeds 4 weight %, the amount of MoS ₂ added is too small, resulting in deterioration of friction properties and increase in electrical noise, resulting in specific wear. The amount is increasing. That is, in the composite brush material for electrical machinery of this invention in which a total of 5% by weight of MoS ₂ powder and NbSe ₂ powder is added to Ag powder, there is a composite brush material in which 4% by weight of MoS ₂ powder and 1% by weight of NbSe ₂ powder is added. The contact resistance, electrical noise, and specific wear characteristics of the material are all better than when MoS ₂ is added alone in the entire current-carrying range. Example 3 Ag powder prototyped in the same manner as Example 1 above
Contact resistance ( _m
Ω) change, electrical noise (mV) change, and specific wear amount (mm ² /mm·N) change were evaluated in the same manner as in Example 1 above. A composite brush material in _which a total of _{25% by weight of MoS 2 powder} and NbSe ₂ powder was added to Ag powder was also used. As with the brush material, contact resistance, electrical noise, and specific wear amount increased when the amount of current applied increased, but when MoS ₂ powder was replaced with NbSe ₂ powder, contact resistance, electrical noise, and specific wear amount were reduced. In each of A, B, and C in Fig. 4, the current density of the composite brush material is 83 (A/cm ² ) when a total of 25% by weight of MoS ₂ powder and NbSe ₂ is added to Ag powder.
Changes in contact resistance (mΩ) and electrical noise (mV) with respect to the amount of NbSe ₂ powder added and the amount of MoS ₂ powder added
Changes in specific wear amount (mm ² /mm・N) are shown.
Regarding the contact resistance, as shown in A in Figure 4,
The composite brush material for electrical machinery of this invention in which MoS ₂ and NbSe ₂ are added together has a NbSe ₂ substitution addition amount of 1% by weight.
The above shows a smaller value compared to the case where MoS ₂ is added alone. Regarding electrical noise, as shown in Fig. 4B, the composite brush material for electrical machinery of the present invention in which MoS ₂ and NbSe ₂ are added together has a NbSe ₂ substitution amount of 1 to 10.
It is reduced in the range of weight % compared to the case where MoS ₂ is added alone. When the amount of NbSe _2- substituted added exceeds 10% by weight, the friction properties deteriorate and electrical noise increases. Regarding the specific wear amount, as shown in Fig. 4C, the composite brush material for electrical machinery of the present invention in which MoS ₂ and NbSe ₂ are added together has a NbSe ₂ substitution amount of 1 to 20.
It is reduced in the range of weight % compared to the case where MoS ₂ is added alone. However, when the amount of MoS ₂ added is less than 4% by weight, the frictional properties deteriorate significantly, and furthermore, electrical noise increases, electrical wear increases, and the specific wear amount also increases. In other words, a total of ₂ MoS powders and ₂ NbSe powders are added to Ag powder.
In the composite brush material for electrical machinery of the present invention containing 25% by weight of NbSe ₂ powder, the composite brush material containing 1 to 10% by weight of NbSe 2 powder has lower contact resistance and electrical resistance than the case where MoS ₂ is added alone in the entire current carrying region. The noise and specific wear characteristics are all good. Example 4 Ag powder prototyped in the same manner as in Example 1 above
The contact resistance, electrical noise, and specific wear amount of a composite brush material containing 12.5% by weight of MoS ₂ powder and 2.5% by weight of NbSe ₂ powder were measured at a current density of 500 (A/cm ² ).
It was evaluated by As a result, the composite brush material for electrical machinery of the present invention has a contact resistance of 9 (mΩ) and an electrical noise of 30 even at a current density of 500 (A/cm ² ).
(mV) and specific wear amount of 1×10 ^-9 (mm ² /mm・N), both of which are small and good. Note that the evaluation test equipment and the like are the same as in Example 1 above. In addition, although not shown in the examples, as shown in the table, other than Ag powder with a total of 5% by weight, 15% by weight, and 25% by weight of MoS ₂ powder and NbSe ₂ powder,
The total amount of MoS ₂ powder and NbSe ₂ powder added is 5 to 25% by weight.
The amount of MoS ₂ powder added is 4 to 24% by weight, and
Those with an added amount of NbSe ₂ powder of 1 to 10% by weight, and
The product to which WS ₂ powder was added also showed the same effect as in the above example. In addition, it is known to use Ag-based composite brush material to which a small amount (1 to 3% by weight) of graphite, which has high lubricity in the atmosphere, is added for ground tests in slip springs for artificial satellites. When applying the composite brush material for electrical machinery, the same treatment may be applied.

【table】

〔Effect of the invention〕

As explained above, this invention is a composite brush material for electrical machinery, which has the following formula: Ag _(100-ab) −(M) _a −(NbSe ₂ ) _b {where M is molybdenum disulfide (MoS ₂ ) and disulfide. It represents at least one type of tungsten (WS ₂ ), Ag is silver, and NbSe ₂ is niobium selenide. a, b are weight concentrations, 4≦a≦24, 1≦b
Represents a number that satisfies the relationships of ≦10 and 5≦a+b≦25. } By using the material shown in , it has good friction and wear characteristics in a wide range of current carrying areas from low current carrying areas to large current carrying areas.
Moreover, it is possible to efficiently obtain a composite brush material for electrical machinery that has excellent conductivity, low contact resistance, and low electrical noise. The composite brush material for electrical machinery of the present invention can be applied, for example, to a signal slip ring in a low current carrying area and a power slip ring in a large current carrying area. In addition, slip rings can maintain excellent sliding characteristics for a long time in ultra-high vacuum where artificial satellites, space structures, etc. are placed. In addition, the composite brush material for electrical machinery of the present invention can be used not only in space but also in special atmospheres on the ground, such as in a vacuum chamber, in a nitrogen gas atmosphere, or in dry air where the lubricating effect of the adsorbed water molecular layer cannot be expected (2 g/
It goes without saying that a similar effect is expected for particles (cm ³ or less).

[Brief explanation of the drawing]

Figure 1 compares the contact resistance, electrical noise, and specific wear of a composite brush material for electrical machinery in which a total of 15% by weight of MoS ₂ powder and NbSe ₂ powder is added to Ag powder according to an embodiment of the present invention and a conventional material. Contact resistance (mΩ) change, electrical noise (mV) change, and specific wear amount (mm ² /mm・N) due to current density (A/cm ² )
FIG. 3 is a characteristic diagram showing changes. In Figure 1, curve 1
curves 2, 3, and 4 are the characteristics of the composite brush material for electrical machinery according to the embodiments of the present invention. Each of FIG. 2 shows the Ag powder of the embodiment of this invention.
Composite brush material for electrical machinery with a total of 15% by weight of MoS ₂ and NbSe ₂ powder added and the current density of the conventional one: 83
The amount of _{NbSe 2} ^added and
Changes in contact resistance (mΩ), electrical noise (mV), and specific wear amount (mm ² /mm・) depending on the amount of MoS ₂ added
N) is a characteristic diagram showing changes. In Figure 2,
Point 1 is the characteristic of MoS ₂ powder added alone to Ag powder, and solid line 5 is the characteristic of the composite brush material for electrical machinery according to the embodiment of the present invention. Each of FIG. 3 shows the Ag powder of the embodiment of this invention.
Composite brush material for electrical machinery with a total of 5% by weight of MoS ₂ powder and NbSe ₂ powder added and the current density of the conventional brush material
83 (A/cm ² ) to compare the contact resistance, electrical noise _, and specific wear amount.
Changes in contact resistance (mΩ), electrical noise (mV), and specific wear amount (mm ² /mm・) depending on the amount of MoS ₂ added
N) is a characteristic diagram showing changes. In Figure 3,
Point 1 is the characteristic of the MoS ₂ powder added alone to Ag powder, and point 6 is the characteristic of the composite brush material for electrical machinery according to the embodiment of this invention. Each of FIG. 4 shows the Ag powder of the embodiment of this invention.
Current density of composite brush material for electrical machinery with a total of 25% by weight of MoS ₂ powder and NbSe ₂ powder added and conventional brush material
83 (A/cm ² ) to compare the contact resistance, electrical noise _, and specific wear amount.
Changes in contact resistance (mΩ), electrical noise (mV), and specific wear amount (mm ² /mm・) depending on the amount of MoS ₂ added
N) is a characteristic diagram showing changes. In Figure 4,
Point 1 is the characteristic of the MoS ₂ powder added alone to the Ag powder, and solid line 7 is the characteristic of the composite brush material for electrical machinery according to the embodiment of the present invention.

Claims (1)

[Claims] 1 Formula: Ag _(100-ab) −(M) _a −(NbSe ₂ ) _b {In the formula, M is one of molybdenum disulfide (MoS ₂ ) and tungsten disulfide (WS ₂ ). Ag represents silver, and NbSe ₂ represents niobium selenide. a, b are weight concentrations, 4≦a≦24, 1≦b
Represents a number that satisfies the relationships of ≦10 and 5≦a+b≦25. } A composite brush material for electrical machinery characterized by: