KR20180067496A - Sliding part and method of producing the sliding part - Google Patents

Abstract

The present invention provides a sliding material of resin coating that has excellent property of tightness with respect to a base material and can suitably prevent the base material from generating dust. The sliding material of the present invention comprises a base material having open air pores and a resin coating that is composed of fusible resin. The resin coating comprises: a coating section for being coated on at least a portion of a surface of the base material; and an anchor section, which is connected to the coating section and filled in the open air pores.

Description

FIELD OF THE INVENTION [0001] The present invention relates to a sliding material,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a sliding member and a method of manufacturing the sliding member, and more particularly, to a sliding member having a resinous coating formed on its surface for preventing dust generation and corrosion and a method of manufacturing the same.

BACKGROUND ART [0002] There is a non-contact sealing apparatus for positively introducing a fluid into a sliding surface to bring seal rings into a noncontact state as a mechanical seal for sealing an enclosed fluid such as a semiconductor manufacturing facility. The noncontact sealing apparatus according to the prior art separates the seal ring by the pressure of the fluid introduced into the sliding surface to prevent dust from being generated due to wear and wear of the seal ring.

However, even in the case of a non-contact sealing apparatus, abrasion of the seal ring may occur when the supply of the fluid to be introduced to the sliding surface is stopped, the rotation speed of the rotation shaft is low, or the like. A technique for forming a coating having self-lubricating property on the surface of a substrate as a technique for preventing the generation of dust due to abrasion and abrasion of the seal ring even under the condition that no fluid film is present between the sliding surfaces (See Patent Document 2, etc.).

2006-22834 Japanese Patent Application Laid-Open No. 2001-26792

However, the coating of the sliding material according to the prior art has insufficient adhesiveness to the substrate, and is easily peeled off from the substrate. There is also an attempt to use a tetrafluoroethylene resin (PTFE) coating excellent in corrosion resistance against a chemical liquid such as a concentrated sulfuric acid as a coating of a sliding material, but such a coating has poor adhesion to a substrate. The inventors have attempted to form a base layer using a resin which is in close contact with a base material and a fluororesin better than the fluororesin, and to form a fluororesin coating on the base layer, but the adhesion of the coating is still insufficient.

In addition, a pinhole may be formed in the coating of the sliding material according to the prior art in some cases, and the base layer or substrate is corroded by the chemical liquid penetrating from the pinhole, and the coating is peeled off. In addition, the sliding material according to the related art has a problem that the coating is easily peeled off by physical force when the coating is made thick to prevent pinholes.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a sliding member having a resin film excellent in adhesion to a substrate and capable of appropriately preventing the generation of dust on the substrate and a method of manufacturing the same.

In order to solve the above-described problems, the sliding member according to the present invention has a base material having an open pore and a resin film made of a molten resin, and the resin film covers at least a part of the surface of the base material And an anchor portion connected to the covering portion and filled in the open pore.

Since the sliding member according to the present invention has not only the covering portion where the resin coating covers the surface of the base material but also the anchor portion filled in the open pores of the base material, the adhesion between the resin coating and the base material is high and the resin coating is not peeled off. Since the sliding member according to the present invention forms the resin coating with the molten resin, it is difficult to form pinholes in the resin coating, and the substrate can be protected with certainty, so that peeling of the coating due to corrosion of the base can be prevented . Further, the sliding material according to the present invention does not peel off the coating from the base material and covers the base material reliably, so that it is possible to suitably prevent the base material from being worn out and generating dust.

Also, for example, the substrate may be carbon. Carbon is a porous material containing a large number of pores, and has pores of a complex shape. Therefore, the sliding material according to the present invention can improve the effect of fixing the resin film by the anchor portion by making the base material carbon.

Also, for example, the carbon may be a hard carbon. By using the base material of hard carbon, it is possible to more effectively prevent the peeling of the resin film by firmly supporting the resin film, which is the irregularities of the surface of the base material and engaging with the irregularities.

For example, the sliding member according to the present invention may have a sliding surface on which the resin film is not formed and a non-sliding surface on which the resin film is formed as a surface other than the sliding surface.

Such a sliding material does not form a resin coating on the sliding surface and exposes the carbon having excellent self-lubricating property, so that wear of the sliding surface can be prevented even in a situation where lubrication by the fluid is hardly obtained. In addition, by forming a resin coating on the non-sliding surface, it is possible to prevent the generation of dust from the substrate and the adhesion of dust to the carbon, and also to protect the substrate from the chemical liquid or the like.

Further, for example, the open pore filled with the same molten resin as the resin film may be formed on the sliding surface on which the resin film is not formed. Since the open pores existing on the sliding surface are filled with the molten synthetic resin, such a sliding material prevents the chemical liquid or the like from penetrating into the substrate through the open pores of the sliding surface and prevents the dust from being generated inside the substrate .

Further, for example, the sliding material according to the present invention may have an impurity content of 5000 ppm or less. Since the corrosion resistance of the substrate itself is improved by setting the impurity content of the substrate to 5000 ppm, peeling of the film due to corrosion of the substrate can be prevented even when the substrate is aerated in the chemical liquid.

Further, for example, the sliding member according to the present invention may have a thickness of 30 mu m or less. Since the sliding member according to the present invention is formed of a molten resin so that the resin coating is hardly formed in the pinhole in the resin coating, it is possible to protect the base material from the chemical liquid even if the covering portion is thinned. Thus, by making the thickness of the covering portion 30 μm or less, such a sliding material is less likely to be disintegrated by the physical force of the resin coating, and peeling of the coating can be effectively prevented.

The molten resin may be fluorine-based resin. Since the fluororesin has excellent corrosion resistance to chemical solutions such as concentrated sulfuric acid, fluorine, chlorine gas and cancellous (bromine), such a sliding material can more effectively protect the substrate from these chemical solutions.

A method of manufacturing a sliding member according to the present invention includes the steps of preparing a base material having open pores, applying a coating material containing a molten resin to the surface of the base material, And a heat treatment at a temperature not lower than the melting point.

In the method of manufacturing a sliding member according to the present invention, when a paint containing a molten resin is applied to the substrate, the paint can be intruded into the open pores of the substrate. Then, the base material coated with the paint is heat-treated at a temperature equal to or higher than the melting point of the molten resin to melt the molten resin contained in the paint, thereby forming the resin film having the anchor portion and the covering portion as described above.

1 is a cross-sectional view of a sealing device including a sliding member according to an embodiment of the present invention.
2 is a flowchart illustrating a method of manufacturing a sliding member according to an embodiment of the present invention.
3 is an electron micrograph of a section of a sliding member according to an embodiment of the present invention.

1 is a sectional view of a sealing apparatus 10 including a first sealing ring 12 and a second sealing ring 14 which are sliding members according to an embodiment of the present invention. The sealing apparatus 10 is a noncontact sealing apparatus that sends a supply fluid between the sliding surfaces by the supply fluid pressure P3 and places the first seal ring 12 and the second seal ring 14 in a noncontact state. Is not limited to the noncontact sealing device.

The sealing device 10 is attached between a housing 60 having a hole and a rotary shaft 50 fitted in the hole. An L-shaped holding portion 40 having a cross section is attached through the two O-rings 65 to the hole on the end of the housing. A second seal ring 14 is movably attached to the peripheral surface of the inner circumference of the holding portion 40 through two O-rings 32. [ The second seal ring 14 is stopped by the snap ring 67 so as not to escape from the inner seal.

A plurality of holes are formed along the main direction (circumferential direction) on the side peripheral surface of the inner circumference of the holding portion 40, and springs 41 are disposed in the respective holes. The spring (41) elastically presses the second seal ring (14) toward the first seal ring (12). Although the illustration is omitted, the holding portion 40 and the second seal ring 14 are engaged with each other by a pin.

A fixing portion 21 is fixedly attached to the rotary shaft 50 through an O-ring 33. [ An O-ring 31 is provided on a side surface of an end portion of the fixing portion 21. A first sealing ring 12 is attached to the fixing portion 21 through an O-ring 31. [ The first seal ring 12 is sandwiched on both sides in the axial direction by the first pressing portion 22 and the fixing portion 21 so that the movement in the axial direction is regulated. Further, the fixing portion 21 and the first pressing portion 22 are fixed to the rotating shaft 50 through the second pressing portion 23. The second pressing portion 23 is screwed to the rotating shaft 50 to fasten the fixing portion 21 and the first pressing portion 22 to each other.

The housing 60 and the holding portion 40 are formed with communication paths 61 communicating with each other. The communication passage (61) communicates with the fluid supply passage (20) of the second seal ring (14). The fluid supply passage 20 of the second seal ring 14 passes through the interior of the second seal ring 14 and passes through the first sliding surface 13 of the first seal ring and the second sliding surface 14 of the second seal ring 14 (15) between the opposite sliding surfaces. And a pipe is connected to the communication passage 61 so as to supply the supply fluid pressure P3 from a fluid supply source not shown.

The enclosed fluid exists on the high pressure side P1 in the cabin and the inside of the cabin outside the cabinet 10 becomes the low pressure side P2. The inside of the chamber may be a low pressure such as a vacuum. The pressure of the supply fluid pressure P3 is kept equal to or higher than the pressure of the high pressure side P1.

The supply fluid supplied from the fluid supply source to the fluid supply passage 20 flows through the fluid supply passage 20 to the first sliding surface 13 and the second sliding surface 15 And flows between the relative sliding surfaces. A fluid guide groove 16 is formed in the first sliding surface 13 of the first seal ring 12 along the main direction. The fluid guide groove 16 extends in the radial direction of the fluid guide groove 16, A dynamic pressure generating groove 18 for generating dynamic pressure is formed. The supply fluid is supplied to the entire surface between the relative sliding surfaces by the fluid guiding grooves 16 and the dynamic pressure generating grooves 18 to bring the relative sliding surfaces into a noncontact state.

Further, on the second sliding surface 15, an introduction passage (not shown) for introducing the sealed fluid of the high-pressure side (P1) into the dynamic pressure generating groove 18 is formed. The sealed fluid of the high pressure side P1 is automatically introduced through the introduction passage into the relative sliding surfaces even when the supply of the supply fluid pressure P3 is stopped unexpectedly. Therefore, even when the supply of the supply fluid pressure P3 is stopped, the sealing device 10 can not move between the sliding surfaces by the introduction flow path for introducing the sealing fluid into the space between the sliding surfaces and by the action of the dynamic pressure generating groove 18, .

<Sliding Material> Hereinafter, the material surfaces of the sealing rings 12 and 14 will be described. The sealing rings 12 and 14 have a base material having open pores and a resin coating made of a molten resin.

<Base material> The base material has substantially the same outer shape as the outer shape of the entire sealing rings 12 and 14. Further, the substrate has open pores which are pores opened on the surface of the substrate. The open pores may be formed by using a porous material such as carbon as a material constituting the base material, or by mechanically or chemically processing a nonporous material such as a metal material.

Examples of the material of the substrate include carbon, silicon carbide, alumina, silicon nitride, zirconia, sialon, chromium oxide, chromium carbide, various cermets and metals. Carbon is preferable. Since carbon is originally a porous material, it can be a substrate having complicated pores on a three-dimensional mesh just by sintering the starting material. When the substrate is made of a porous material such as carbon, the porosity (saturation method, JCAS-11) of the base material has a predetermined amount or more of open pores and the bending strength (about 60 MPa) But it is not particularly limited.

When the substrate is made of carbon, it is more preferable that the carbon is hard carbon. The Shore hardness HsD of the preferred hard carbon is 80 or more. When the substrate is made of hard carbon, since the resin film of the base surface is firmly supported by the irregularities, the sealing rings 12 and 14 can more effectively prevent the resin film from being peeled off.

When the substrate is made of carbon, the carbon component may be any of graphite and carbonaceous materials, but it is preferably carbonaceous from the viewpoint of preventing the peeling of the resin film, and the preferable degree of graphitization of carbon constituting the substrate is 50 % Or less. Since the graphitic carbon tends to have a strong hydrophobic property, the carbon of the base material is made of carbonaceous material, so that the ingestion of the liquid in the coating of the coating material can be satisfactorily maintained, and the coating material can be easily guided into the open pore. Accordingly, by making the substrate a carbonaceous carbon, it is possible to form a resin film having more anchor portions, and a sliding member having a resin film which is less likely to be peeled off can be formed. Furthermore, by making the carbon of the base material carbon-carbon, the chemical solution reacts with the graphite component of the base material to form an intercalation compound peculiar to graphite, thereby suppressing the phenomenon of peeling of the resin film.

The content of the impurities contained in the substrate is preferably 5000 ppm or less from the viewpoint of improving the corrosion resistance. Among the impurities contained in the base material, iron tends to promote corrosion of the base material, and it is particularly preferable that the content of Fe contained in the base material is 1000 ppm or less.

&Lt; Resin coating film > Fig. 3 is an electron micrograph of a section of the sealing rings 12 and 14, which are sliding members according to an embodiment of the present invention. As shown in Fig. 3, the resin coating has a covering portion 72 covering at least a part of the surface of the base material 70 and an anchor portion 74 filled in the open pore. The anchor portion 74 is connected to the covering portion 72 and exhibits an effect of enhancing the adhesion of the resin coating to the base material 70 by anchoring the covering portion 72 to the surface of the base material 70.

The resin coating may be formed on the whole of the sealing rings 12 and 14. When the base material 70 is made of carbon, the resin coating is not formed on the sliding surfaces 13 and 15 The resin coating can be formed on the non-sliding surface, which is a surface other than the sliding surfaces 13 and 15. [ Since the sliding surfaces 13 and 15 are supplied with the supply fluid through the dynamic pressure generating grooves 18 and the like, they are hard to come into contact with the chemical liquid in the fluid to be enclosed. Therefore, even when the sliding surfaces 13 and 15 are in contact with each other, for example, when the rotating speed of the rotating shaft 50 is lowered by exposing carbon having excellent self-lubricating performance, wear of the sliding surface can be prevented.

The resin coating is composed of a molten resin which is melted by heating. As the molten resin used for the resin coating, a fluorine-based resin and the like can be mentioned. In order to obtain a sliding material having excellent corrosion resistance particularly to a chemical liquid such as concentrated sulfuric acid, fluorine, chlorine gas and cancellation, it is preferable that the molten resin constituting the resin coating is a fluorine resin. Among the fluorine-based resins, the meltable resin constituting the resin film is preferably a copolymer of tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), tetrafluoroethylene / ethylene It is particularly preferable that the copolymer (ETFE) is apt to be melted at the time of heat treatment and a resin film with few defects can be formed.

By constituting the resin coating with the molten resin, it becomes possible to form the resin coating by melting the molten resin on the surface of the substrate as described later. The resin film thus formed has good adhesion with a substrate and has few defects such as pinholes. The thickness of the covering portion 72 shown in Fig. 3 is not particularly limited, but is preferably 30 m or less. By setting the thickness of the covering portion 72 to 30 mu m or less, it is possible to prevent the resin coating from being collapsed by mechanical force, and to prevent the resin coating from peeling off from the base.

<Production of Sliding Material> FIG. 2 is a flowchart for explaining an example of the manufacturing method of the sealing rings 12 and 14 of the present invention. In step S01 shown in Fig. 2, a substrate is prepared. The substrate is prepared by a method according to the constituent materials such as molding, firing, sintering, and machining.

When the substrate is constituted by carbon, the substrate is produced by molding the raw material and sintering the raw material. As the raw material, a carbonaceous raw material (coke), artificial graphite, or natural graphite may be blended with a binder (coar tar pitch), or a mesophase having a self-sintering property, a bulk mesophase, or the like may be used.

It is preferable that the graphite component contained in the raw material is suppressed from the viewpoint of satisfactorily retaining the paint content when the paint is applied with the carbonized carbon as the substrate after sintering. From the viewpoint of improving the corrosion resistance of the base material, it is preferable to use a high-purity carbon raw material for the base material. The sintering temperature for sintering the raw material is not particularly limited, but from the viewpoint of preventing the graphitization of the raw material component, it is preferable that the sintering temperature is set to about 1000 占 폚 to 2200 占 폚.

In step S02 shown in Fig. 2, surface treatment of the substrate is performed. When the base material is not a porous material such as carbon, surface treatment such as sandblasting may be performed in step S02 to form open pores in the base material. When the base material is a porous material such as carbon, the surface of the base material may be polished or the like as necessary in step S02 to adjust the surface roughness of the base material.

In step S03 shown in Fig. 2, the base material immediately before the application of the coating material is heated. Then, in step S04, the surface of the base material, which is heated and raised in temperature, is coated with a paint made of a dispersion of a molten resin. It is preferable that the temperature for heating the substrate is 50 占 폚 to 100 占 폚. However, if the base material is porous or has good fusion property with the coating material, there is no problem even if it is at room temperature. By applying the paint in the state that the base is heated to such a temperature, the paint can easily penetrate into the irregularities formed on the surface of the base such as open pores of the base. In addition, by allowing the paint to enter the open pores of the substrate in the coating step (step S04), it is possible to appropriately form the resin coating having the anchor part in the heat treatment step (step S05) described later. In the present embodiment, the coating of the paint is performed on the entire surface of the substrate, but only a part of the coating may be performed by masking the portion not to be coated.

In Step S05 shown in Fig. 2, the substrate coated with the paint is heat-treated at a temperature slightly higher than the melting point or melting point of the molten resin contained in the paint and then cooled to form a resin film having an anchor portion and a covering portion . The molten resin contained in the paint is melted by the heat treatment process (step S05), and a resin film having good continuity and few defects is formed on the surface of the substrate.

In the heat treatment step (step S05), since the molten resin is melted in the same manner as the resin contained in the paint existing on the surface of the molten water guidance base material contained in the paint penetrating into the open pores of the substrate in the coating step (step S04) An environment that is easy to break into is formed. Therefore, in the heat treatment step (step S05), at least the vicinity of the opening of the open pores is filled with the molten resin penetrated into the open pores, and at the same time, the molten resin (covered portion) existing on the surface and the molten resin The anchor portion) is also secured.

In step S06 shown in Fig. 2, the sliding surface is lapped, and the covered portion of the resin coating formed on the sliding surface is removed. By the lapping process (step S06), the carbon substrate having excellent self-lubricating property can be exposed to the sliding surface. Further, since the anchor portion which is a part of the resin coating formed in the heat treatment process (step S05) remains in the open pore of the wrapped sliding surface, open pores filled with the same molten resin as the resin coating covering the non- Respectively. As a result, the seal rings 12 and 14 prevent the entry of the chemical solution into the substrate through the open pores existing in the sliding surfaces 13 and 15, and prevent the generation of dust from the inside of the substrate have.

Since the sealing rings 12 and 14 manufactured as described above have a resin coating covering the surface of the substrate, it is possible to prevent the occurrence of dust on the substrate and to prevent dust from sticking to the substrate. Therefore, the sealing device 10 using such a sealing ring is suitably used for dust-dislike devices such as semiconductor manufacturing facilities.

Further, since the sealing rings 12 and 14 have the anchor portion filled in the open pores of the base material, not only the covering portion covering the surface of the base material, the adhesion between the resin film and the base material is high and the resin film is peeled Do not. In particular, the sealing rings 12 and 14 made of a fluorine resin such as PFA, FEP, or ETFE have excellent corrosion resistance to concentrated sulfuric acid and the like.

According to the above-described manufacturing method, since the sealing rings 12 and 14 having high adhesiveness between the substrate and the resin can be manufactured, the sealing ring 12, which exhibits the effect of preventing dust, , And (14) can be manufactured by a simple manufacturing method that does not require formation of a primer layer.

EXAMPLES Hereinafter, the present invention will be described based on examples, but the present invention is not limited to these examples.

[Example 1] In Example 1, a sliding material was formed according to the manufacturing process described in the above-described embodiment, and then a corrosion test was conducted on the sliding material.

In Example 1, the substrate was produced by sintering the calcined cokes and coar tar pitch as starting materials at 1500 ° C (step S01 in FIG. 2). The shape of the substrate was a circular plate of? 41xL17mm. The analysis of the physical properties of the substrate revealed that the porosity (trapping method) was 20%, the amount of impurities (residue after combustion at 900 캜) was 800 ppm and the Fe content (X-ray analysis of residue) (About 25% of the residue), and the degree of graphitization (the method of analysis) was 5%. The surface roughness of the substrate was polished so that the surface roughness Rz (JIS B0601-1994) was 12.5Z (step S02 in Fig. 2).

Next, the produced substrate was subjected to ultrasonic cleaning in pure water and then dried. 2). After applying the spray liquid (concentration 15%) of the molten resin to the base material at the room temperature, the base material was heat-treated at 380 캜 (step S05 in Fig. 2) . Table 1 shows the manufacturing conditions and the material analysis results of the sliding member according to the first embodiment. The substrate heating process (step S03) and the lapping process (step S06) shown in Fig. 2 are not performed.

Base material Sintering temperature
(° C) Material analysis result Method of forming resin film Raw material 1 Raw material 2 Raw material 3 Porosity
(%) Impurity content
(ppm) Fe component (ppm) Graphitization degree
(%) Example 1 Calcined coke Coole tar pitch - 1500 20 800 200 5 Method 1 Example 2 Calcined coke Coole Tar
pitch - 2800 15 400 20 50 Method 1 Example 3 Calcined coke Coole tar pitch Artificial graphite 1500 18 700 100 50 Method 1 Example 4 bulk
Mesophase - - 2000 5 500 100 10 Method 1 ' Reference Example 1 Calcined coke Coole tar pitch Natural graphite 1200 12 70000 3500 30 Method 1 Reference Example 2 Calcined coke Coole tar pitch - 1500 20 800 200 5 Method 2

In Example 1, nine kinds of samples (sliding members) having the same base material but different coating thicknesses of the resinous coating of the molten resin and the resinous coating were produced. That is, for the three types of molten resin (PFA, FEP, ETFE), sliding members having thicknesses of 5 μm, 10 μm, and 30 μm were prepared, respectively. The thickness of the covering portion was adjusted by repeating the coating step (step S04 in Fig. 2).

The corrosion test was carried out to evaluate the adhesion strength of the resin film after immersing the prepared sliding materials in 100% sulfuric acid for 99 hours. The tape peeling strength was measured in accordance with JIS K5400 (board neck test). The evaluation results are shown in Table 2.

Coat
material PFA FEP ETFE Coat
Thickness (μm) 5 10 30 5 10 30 5 10 30 evaluation
Time (hrs.) 100 300 100 300 100 300 100 300 100 300 100 300 100 300 100 300 100 300 Example 1 ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Example 2 ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Example 3 ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Example 4 ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Reference Example 1 △ △ △ △ ○ △ △ △ △ △ ○ △ △ △ △ △ ○ △ Reference Example 2 △ △ △ △ ○ △ △ △ △ △ ○ △ △ △ △ △ ○ △ ?: Peeling of the resin film?: Peeling of the resin film?

[Example 2] In Example 2, a sliding material was formed in the same manner as in Example 1 except that the sintering temperature at the time of sintering the base material was changed to 2800 캜, and the same sliding material as in Example 1 was subjected to a corrosion test .

By analyzing the physical properties of the substrate according to Example 2, the porosity was 15%, the amount of impurities was 400 ppm, the content of Fe was about 20 ppm (about 5% of the residue), and the degree of graphitization was 50%. Table 1 shows the production conditions and material analysis results of the sliding material according to Example 2, and Table 2 shows the results of the corrosion resistance test.

[Example 3] In Example 3, a sliding material was formed in the same manner as in Example 1 except that artificial graphite was added to the base material, and the same sliding material as in Example 1 was subjected to a corrosion test.

Analysis of the physical properties of the substrate according to Example 3 revealed that the porosity was 18%, the amount of impurities was 700 ppm, the content of Fe was about 100 ppm (about 15% of the residue), and the degree of graphitization was 50%. Table 1 shows the production conditions and material analysis results of the sliding material according to Example 3, and Table 2 shows the results of the corrosion resistance test.

[Example 4] In Example 4, except that a bulk mesophase was used as a base material and the base was heated to 60 占 폚 (step S03 was carried out) and the dispersion of the molten resin was applied, the sintering temperature was changed to 2000 占 폚 A sliding member was formed in the same manner as in Example 1, and the same sliding member as in Example 1 was subjected to a corrosion test. When the dispersion liquid of the molten resin was applied, the base material was heated to 60 캜 so that the base material according to Example 4 had a low porosity, so that the paint could easily enter the open pores of the base material.

The physical properties of the substrate according to Example 4 were analyzed. The porosity was 5%, the amount of impurities was 500 ppm, the content of Fe was about 100 ppm (about 20% of the residue), and the degree of graphitization was 10%. The results of the corrosion resistance test are shown in Table 1 and Table 2, respectively.

[Reference Example 1] In Reference Example 1, a sliding material was formed in the same manner as in Example 1 except that natural graphite as a low-purity carbon material was added to the base material and the sintering temperature was changed to 1200 캜. A corrosion test of the same sliding material was carried out.

The physical properties of the substrate according to Reference Example 1 were analyzed. The porosity was 12%, the amount of impurities was 70000 ppm (7%), the content of Fe was about 3500 ppm (about 5% of the residue) and the degree of graphitization was 30%. Table 1 shows the production conditions and material analysis results of the sliding member according to Reference Example 1, and Table 2 shows the results of the corrosion resistance test.

[Reference Example 2] In Reference Example 2, a sliding member was formed in the same manner as in Example 1 except that the resin film forming method was changed, and the same sliding member corrosion test as in Example 1 was carried out. The resin film formation method according to Reference Example 2 is the same as Embodiment 1 except that a step of forming a primer layer on the surface of the substrate after step S02 shown in Fig. 2 is added.

In Reference Example 2, after completion of the substrate surface treatment step (Step S02), the substrate was subjected to ultrasonic cleaning, and then a primer layer was formed by applying a primer layer coating containing P, Fr and a fluorine resin on the surface of the substrate. Then, steps S04 to S05 shown in Fig. 2 were carried out in the same manner as in Example 1 to form a film on the primer layer.

As shown in Table 2, peeling of the resin film was not observed in the measurement of the tape peeling strength after immersion in sulfuric acid in Examples 1 to 4. On the other hand, in Reference Example 1, peeling of the coating resin was observed in the measurement of the tape peeling strength after the immersion in sulfuric acid, and the adhesion of the resin coating to the substrate was decreased. Further, in Reference Example 2, peeling of the resin coating was observed for samples having coating thicknesses of 5 占 퐉 and 10 占 퐉, and adhesion of the resin coating to the substrate was lowered. With respect to the sample having the coating film thickness of 30 m in Reference Examples 1 and 2, the peeling of the coating film was not observed for the evaluation time of 100 hours, but peeling was observed in Reference Examples 1 and 2 when the evaluation time was 300 hours.

Comparing the samples according to Examples 1 to 4 with the samples according to Reference Example 1, it can be seen that the content of impurities contained in the base material and the Fe content are greatly different as shown in Table 1. In Reference Example 1, since the impurity content and the Fe content of the substrate are large, the substrate itself is likely to be corroded by concentrated sulfuric acid. Therefore, in Reference Example 1, corrosion of the substrate itself progressed slightly although it was caused by immersion of sulfuric acid, and the adhesion of the resin film to the substrate decreased. On the contrary, in the samples according to Examples 1 to 4, since the impurity content and the Fe content of the substrate were small, corrosion of the substrate did not proceed even by sulfuric acid immersion, and the adhesion of the resin film to the substrate was maintained.

As compared with the sample according to Example 1 and the sample according to Reference Example 2, only the resin film forming method is different as shown in Table 1. The coating film formed on the sliding material according to Reference Example 2 is different from that of Example 1, and the anchor portion filled in the open pores of the base material and the covering portion of the base material surface are connected (See Fig. 3). Therefore, the coating of Reference Example 2 is inferior in adhesiveness to the resin coating of Example 1, and it is considered that peeling occurred in some samples. On the contrary, it is considered that the sliding material according to the first embodiment has good adhesion of the resin film to the base material, because the anchor portion filled in the open pores of the base material and the resin coating to which the covering portion of the base material surface is connected.

Claims (6)

1. A hard carbon having open pores, wherein the substrate has an impurity content of 5,000 ppm or less,
A resin film made of any one of fluorine-based fusible resins such as PFA, FEP and ETFE,
Wherein the resin coating has a covering portion covering at least a part of the surface of the substrate and an anchor portion connected to the covering portion and filled in the opening. The method according to claim 1,
A sliding surface on which the resin coating is not formed and a non-sliding surface on which the resin coating is formed on a surface other than the sliding surface. The sliding member according to claim 2, wherein the sliding surface is formed with the open pores filled with the same fluoric molten resin as the resin coating. 4. The method according to any one of claims 1 to 3,
Wherein the impurity content of the base material is 5,000 ppm or less. 4. The method according to any one of claims 1 to 3,
Wherein the substrate is a carbonaceous hard carbon having a Shore hardness HsD of 80 or more. 4. The method according to any one of claims 1 to 3,
And the Fe component contained in the base material as an impurity is 1000ppm or less.

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