JP2005214382A - High-strength slide member and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the following problem: a conventional slide member can not sufficiently prevent intrusion of hydrogen produced from decomposition of lubricating oil into a base material. <P>SOLUTION: On the surface of the base material 1, a hard film 2 is formed which hardly causes adhesion to an opposed member in slide contact. The hard film 2 is constituted of a high-strength slide member which contains a hydrogen-inhibiting substance. Thus, generation of a new surface produced in consequence of metallic contact with the opposed member is inhibited, and generation of hydrogen due to decomposition of the lubricating oil is restrained. Effusion of the hydrogen-inhibitor consequent upon abrasion is inhibited, and generated hydrogen is prevented from intruding into the base material 1 by the hydrogen-inhibitor in the hard film 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a high-strength sliding member that can be applied to various sliding members that are in sliding contact with a driving portion of an automobile, for example, and a method for manufacturing the same.

  In recent years, automobiles that use motors as drive sources are expected to increase in response to environmental problems. Such automobiles require gears for reduction gears that reduce the rotation of motors in the order of tens of thousands of rpm in a compact size, such as wear due to high-speed sliding, scuffing and flaking. There is a demand for a high-strength material that can withstand surface damage and bending stress that is frequently repeated. In order to cope with such surface damage and bending stress, it is an effective means to increase the surface hardness of the material.

  However, in sliding members such as bearings, minute metal contact on the surface accelerates the decomposition of the lubricating oil, and hydrogen generated thereby penetrates into the base material, greatly increasing the life of the sliding member. It has been found that there may be a decline. In such a case, increasing the hardness of the material may increase the sensitivity to hydrogen embrittlement and may reduce the strength of the member.

Therefore, in the past, as a measure to suppress the penetration of hydrogen into the base material of the sliding member, a method of improving the life by performing shot peening on the base material surface, metal contact and subsequent hydrogen penetration For the purpose of slowing the speed, methods such as black dyeing treatment, wet plating of Cu, Ni and the like on the base material and a method by Cr ion sputtering have been proposed.
JP 2003-148777 A JP 2000-291757 A JP-A-2-190615 JP-A-5-345975

  However, in the conventional sliding member as described above, the method using shot peening does not prevent the generation of hydrogen and the penetration into the base material only by delaying the progress of microcracking, and In all of the methods of wet plating with black dyeing treatment or Cu, Ni, etc., the film is lost early due to sliding contact with the mating member, and in the case of electrical plating, hydrogen is used instead of the base material when the film is formed. There was a problem of letting it invade.

  Furthermore, the method using Cr ion sputtering is effective in that a relatively hard surface is obtained and hydrogen does not enter during the formation of the coating because of the treatment in vacuum. There was a problem that the generated active new surface could not prevent the decomposition of the lubricating oil and the intrusion of hydrogen.

  The present invention was made paying attention to the above-mentioned conventional problems, and aims to provide a high-strength sliding member capable of suppressing the generation of hydrogen and the intrusion into the base material. A hard film that hardly adheres to a mating member that is in sliding contact is formed on the surface, and the hard film contains a hydrogen-suppressing substance. Here, the hydrogen suppressing substance includes a hydrogen adsorbing substance that adsorbs hydrogen and a hydrogen diffusion suppressing substance that suppresses the diffusion of hydrogen. When a hydrogen adsorbing substance is used, it is included in the hard film as a dispersion or layer. When a hydrogen diffusion inhibitor is used, it can be included as a layer in the hard film.

  The method for producing a high-strength member of the present invention is characterized in that a hard film is formed by ion sputtering, particularly when the hydrogen suppressing substance is a hydrogen adsorbing substance. In this case, a hard film is formed by an ion plating method or an ion sputtering method in which the temperature during film formation is 200 to 250 ° C.

  According to the high-strength sliding member of the present invention, on the surface of the base material, a hard film that hardly adheres to the mating member that is in sliding contact is formed, and the hard film contains a hydrogen suppressing substance. Thus, it is possible to suppress the generation of a new surface due to metal contact with the mating member, to suppress the generation of hydrogen due to the decomposition of the lubricating oil, and to suppress the outflow of the hydrogen inhibiting substance due to wear. Even if metal contact occurs due to protrusions having a surface roughness of about a degree of sliding contact with the member, the hydrogen suppressing substance in the hard film can prevent the generated hydrogen from entering the substrate.

  Further, according to the method for manufacturing a high-strength sliding member of the present invention, a hard film is formed by ion sputtering, particularly when the hydrogen suppressing substance is a hydrogen adsorbing substance. A high-strength sliding member provided with a hard film that can suppress softening of the material and has sufficient adhesion to the base material can be obtained.

  Further, particularly when the hydrogen suppressing substance is a hydrogen diffusion suppressing substance, a hard film is formed by an ion plating method or an ion sputtering method in which the temperature during film formation is 200 to 250 ° C. Softening of the substrate can be prevented, and since it is a treatment in vacuum, hydrogen does not enter the substrate during film formation, and hydrogen that has entered the substrate during heat treatment or machining is released. A high-strength sliding member provided with a hard film having sufficient adhesion to the substrate and having toughness can be obtained.

  The high-strength sliding member of the present invention forms on the surface of the base material a hard film that hardly adheres to the mating member that is in sliding contact, and the hard film contains a hydrogen-suppressing substance. ing. At this time, as the hydrogen suppressing substance, a hydrogen adsorbing substance having a function of adsorbing hydrogen and a hydrogen diffusion inhibiting substance that inhibits hydrogen diffusion can be used.

  When a hydrogen adsorbing substance is used as the hydrogen suppressing substance, the hydrogen adsorbing substance can be contained in a state dispersed in the hard film. At this time, even if the amount of dispersion of the hydrogen adsorbing material is small, the effect of hydrogen adsorption can be exhibited, but in order to obtain a more reliable hydrogen adsorption effect, it is desirable to be 0.3 atomic weight% or more. .

  In this way, by forming a hard film on the surface of the base material and diffusing a hydrogen adsorbing substance in the hard film, the generation of a new surface due to metal contact with the counterpart member is suppressed, and the lubricant is decomposed. In addition to suppressing the generation of hydrogen, it is possible to suppress the outflow of hydrogen-adsorbing substances due to wear, and even if metal contact occurs due to protrusions with a surface roughness of about the surface roughness during sliding contact with the mating member, The hydrogen adsorbing substance in the film can adsorb the produced hydrogen and prevent hydrogen from entering the substrate.

  Further, when a hydrogen adsorbing substance is used as the hydrogen suppressing substance, this hydrogen adsorbing substance can be contained in the state of a layer. More specifically, the hard film is formed on the substrate side or in the film with hydrogen. It may have a hydrogen adsorption layer made of an adsorbing substance. At this time, even if the thickness of the hydrogen adsorption layer is small, the effect of hydrogen adsorption can be exhibited. However, in order to form the layer without breaks, it is desirable that the thickness be 0.1 μm or more.

  As described above, by forming a hard film on the surface of the base material and including the hydrogen adsorption layer in the hard film, the same effect as that obtained by dispersing the hydrogen adsorbing substance in the hard film can be obtained. The hydrogen adsorption layer can provide a stable hydrogen adsorption effect over the entire sliding contact surface, and can improve the toughness and adhesion of the hard film.

  Further, as a more preferred embodiment, the high-strength sliding member can be formed of a hard film of diamond-like carbon (DLC), which is a hard carbon coating, and at this time, at least from the outermost surface to a depth of 1 μm. Shall not contain any hydrogen-suppressing substances.

  In this way, if the hard film is formed of diamond-like carbon, diamond-like carbon is particularly excellent in that it does not easily adhere to metal and has high strength, so at least the outermost layer up to a depth of 1 μm has hydrogen adsorption. No substance (hydrogen suppression substance) is required, hydrogen contained in the lubricating oil on the sliding contact surface does not enter directly, and the hydrogen adsorbing substance contained in the lower layer than the outermost layer allows metal contact with the mating member. Only the produced hydrogen can be adsorbed.

Further, in the high-strength sliding member, a material selected from Ni, Pd, Ti, Zr and a compound containing these metals can be used as the hydrogen adsorbing substance. At this time, as the compound, an intermetallic compound, an alloy, an oxide, or the like is used. For example, in Ti, TiN, TiAlN, Ti ₂ O ₃ or the like is used. Thereby, the said high intensity | strength sliding member can raise hydrogen adsorption power further.

  As described above, in the case of manufacturing a high-strength sliding member in which the hydrogen suppressing substance is a hydrogen adsorbing substance, a hard film can be formed by ion sputtering. Thereby, while being able to suppress softening of the base material by the temperature rise at the time of film-forming, the high intensity | strength sliding member provided with the hard film | membrane which has sufficient adhesiveness with respect to a base material can be obtained.

  Although the high-strength sliding member of the present invention can be manufactured by other methods, when a bending fatigue strength is also required, such as a gear, for example, the substrate due to a temperature rise during film formation It is preferable to use an ion sputtering method from the viewpoint that the softening of the film can be suppressed and the adhesion of the hard film can be easily secured.

  Next, when a hydrogen diffusion inhibiting substance is used as the hydrogen inhibiting substance contained in the hard film, the high-strength sliding member has, as a preferred embodiment, a hydrogen diffusion inhibiting substance comprising a hydrogen diffusion inhibiting substance in the hard film. It can have a layer.

  That is, by forming a hard film on the surface of the base material and providing a hydrogen diffusion inhibiting layer in the hard film, generation of a new surface due to metal contact with the counterpart member is suppressed, and hydrogen generated by decomposition of the lubricating oil In addition, it is possible to suppress the outflow of the hydrogen diffusion inhibiting substance due to wear, and even if metal contact is caused by protrusions with a surface roughness of about the surface roughness during sliding contact with the mating member, The hydrogen diffusion inhibiting layer in the film can inhibit the diffusion of the produced hydrogen and prevent hydrogen from entering the substrate.

  Even when a hard film including a hydrogen diffusion inhibiting layer is provided on the surface of the substrate as described above, the hard film is made of diamond-like carbon (DLC), which is a hard carbon film, as in the case of using the hydrogen adsorbing material. In this way, if the hard film is formed of diamond-like carbon, no hydrogen suppression substance is required on the outermost layer, and hydrogen contained in the lubricating oil on the sliding contact surface may directly invade. In addition, hydrogen diffusion caused by metal contact with the mating member can be suppressed by the hydrogen diffusion suppression layer provided below the outermost layer.

When a hydrogen diffusion inhibitor is used as the hydrogen inhibitor contained in the hard film, as a more preferred embodiment, the base material is made of an iron-based alloy, and the hard film has a Vickers hardness of 1000 or more. The hydrogen diffusion inhibiting layer in the hard film is preferably made of a metal having a density of 8 g / cm ³ or more or a compound thereof.

At this time, the hardness of the hard film is set to Vickers hardness of 1000 or more. When the hardness is less than 1000, the wear resistance of the hard film is lowered and the hydrogen diffusion suppressing layer is worn, and thereby the hydrogen diffusion suppressing effect is insufficient. This is because the density of the metal or the compound forming the hydrogen diffusion suppressing layer is set to 8 g / cm ³ or more. When the density is less than 8 g / cm ³ , the effect of absorbing the deformation of the hard film is obtained. This is because there is a risk of shortage.

  In the high-strength sliding member having the above-described configuration, the hydrogen diffusion suppressing layer made of a high-strength and high-density metal or metal compound suppresses hydrogen diffusion particularly to the strain concentration portion in the sliding member, and the hard film. In addition, it is possible to prevent wear of the hydrogen diffusion suppressing layer in the hard film and maintain the hydrogen diffusion suppressing effect, and the above hydrogen diffusion suppressing layer absorbs deformation of the hard film and reduces its internal stress. Since it relaxes, the toughness and adhesion of the hard film can be improved.

  Further, in the high-strength sliding member, when the base material is made of an iron-based alloy as described above, the hard film is preferably made of iron or an iron compound. In this way, if the material of the base material and the hard film are the same type, the properties such as the elastic modulus and thermal expansion coefficient of both will be close, and the generation of internal stress during film formation and the generation of strain during use of the member Moreover, sufficient toughness and adhesion of a hard film can be obtained even in film formation at a relatively low temperature of about 200 to 250 ° C. without causing the base material made of an iron-based alloy to be softened. .

  Furthermore, in the high-strength sliding member, a material selected from Ni, Cd, Cu, and W can be used as a hydrogen diffusion inhibiting substance that forms the hydrogen diffusion inhibiting layer. In terms of toughness, it becomes even better.

  As described above, in the case of manufacturing a high-strength sliding member in which the hydrogen suppressing substance is a hydrogen diffusion suppressing substance, the material is hardened by an ion plating method or an ion sputtering method in which the temperature during film formation is 200 to 250 ° C. A film can be formed. This can prevent softening of the base made of iron-base alloy in particular, and since it is a treatment in a vacuum, hydrogen does not enter the base during film formation, and also during heat treatment and machining. In this case, hydrogen that has entered the substrate can be released, and a high-strength sliding member having a hard film having sufficient adhesion to the substrate and having toughness can be obtained.

  The manufacturing method of the above-described high-strength sliding member is suitable for manufacturing a sliding member that requires the fatigue strength of the inside of the member and the gear teeth, such as a carburized and quenched and tempered gear. Sufficient adhesion and toughness of the film can be secured, and sufficient member strength and fatigue strength can be obtained.

  In order to examine the effect of the high-strength sliding member of the present invention, the following roller pitting test was performed. In the roller pitting test, as shown in FIG. 3, the evaluation roller R 1 is mounted on the drive shaft 21 that is rotationally driven by a motor, and the driven shaft 23 is interposed between the drive shaft 21 and the speed reducer 22. Further, a counter roller R2 having a diameter larger than that of the evaluation roller R1 is mounted, and the outer peripheral surface of the evaluation roller R1 is pressed against the outer peripheral surface of the counter roller R2 by a load device that increases the dead weight load by a lever. Then, the drive shaft 21 is driven to rotate to rotate the evaluation roller R1, and at the same time, the counter roller R2 is rotated together with the driven shaft 23 to cause slippage due to deceleration between both the rollers R1 and R2, and the evaluation roller Pitting occurring in R1 is detected by the detection device 24.

  In Examples 1 to 5 and Comparative Examples 1 to 5, JIS SCM420H was used for the base material of the evaluation roller corresponding to the high-strength sliding member and the material of the mating roller that was in sliding contact with this. JIS SCM420H is C: 0.17 to 0.23 mass%, Si: 0.15 to 0.35 mass%, Mn: 0.55 to 0.90 mass%, Cr: 0.85 to 1.25 mass% %, And Mo: steel for mechanical structure containing 0.15 to 0.35. Each of the rollers was carburized to a surface hardness of Hv740 and then finished with a surface roughness of Ra 0.2 μm. Thereafter, the evaluation roller was washed with alkali, and a hard film was formed on the surface of the substrate by multi-target ion sputtering using a plurality of ion emission sources.

  In Examples 1 to 3, as shown in FIG. 1A, a hard film 2 made of diamond-like carbon (DLC) is formed on the surface of the substrate 1, and at this time, hydrogen is formed on each hard film 2. Ni, Zr and Ti were contained in a dispersed state as adsorbing substances (hydrogen suppressing substances).

  In Example 4, as shown in FIG. 1B, a hard film 3 made of diamond-like carbon (DLC) is formed on the surface of the substrate 1, and at this time, the hard film 3 is composed only of diamond-like carbon. And a lower layer 3b containing Pb in a dispersed state as a hydrogen adsorbing substance in diamond-like carbon.

  In Example 5, as shown in FIG. 1C, a hard film 4 made of diamond-like carbon (DLC) is formed on the surface of the substrate 1, and at this time, the hard film 4 is composed of only diamond-like carbon. The upper layer 4a is made of a hydrogen adsorption layer 4b made of Pb which is a hydrogen adsorption material.

In Comparative Example 1, only the base material 1 was used as shown in FIG. For Comparative Example 2, as shown in FIG. 1 (e), the surface of the substrate 1 was subjected to black dyeing treatment 5. The black dyeing treatment is a rust prevention treatment that produces black rust (Fe ₃ O ₄ ) on the surface of the substrate. Here, after pickling with 5% dilute hydrochloric acid, black dyeing is performed with a commercially available Super Blue dyeing solution. Processed.

  In Comparative Example 3, as shown in FIG. 1 (f), a film 6 made of diamond-like carbon (DLC) was formed on the surface of the substrate 1. In Comparative Examples 4 and 5, as shown in FIG. 1 (g), a film 7 made of diamond-like carbon (DLC) is formed on the surface of the substrate 1, and at this time, each of the films is made of Al, Fe was contained in a dispersed state.

  In Examples 1 to 5 and Comparative Examples 2 to 5, the thicknesses of the hard film and the coatings 2 to 7 are 2 to 4 μm. In particular, in Examples 4 and 5, the thickness of the upper layers 3a and 4a. Was 0.2 μm, and the remainder was the lower layer 3b and the hydrogen adsorption layer 4b. In Examples 1 to 4 and Comparative Examples 4 and 5, the content of the dispersed metal was about 1 atomic weight%.

The shape of the roller pitting test piece and the ion sputtering film forming conditions are as follows.
<Roller pitting test piece shape>
Evaluation roller outer diameter: 26 mm
Roller crowning for evaluation: None (flat)
Counter roller outer diameter: 130 mm
Counter roller crowning: R150 mm
<Ion sputtering film formation conditions>
Degree of vacuum before introducing nitrogen gas: 1 × 10 ^{−3 to} 5 × 10 ⁻⁵ Torr
Bias voltage during film formation: 100V
Pre-deposition temperature: 200-250 ° C
Total film thickness: 2-4 μm

Then, under the following test conditions, a roller pitting test was performed until the evaluation roller peeled or reached 10 ⁷ cycles, and after the test, the remaining state of the hard film and the structure observation of the cross section of the peeled portion were performed. Moreover, the amount of hydrogen released from room temperature to 400 ° C. after the test was measured as the amount of hydrogen penetrating into the substrate.
<Roller pitting test conditions>
Load: 460kg
Rotation speed: 1500rpm
Slip rate: -60%
Oil temperature: 110 ° C
Supply oil volume: 1 l / min

  Table 1 summarizes the results. In the case of the test oil used in the above test, when the target member is ordinary steel, hydrogen embrittlement type pitting occurs and the coating peels off early (about 1/10 of ordinary oil). Therefore, the film remains in the above test, and if it functions, the life is about ten times longer.

  As is clear from Table 1, in Comparative Example 1, as shown in FIG. 4, a hydrogen embrittlement-like structural change was observed, and peeling occurred in a short life. Moreover, in Comparative Example 2 and Comparative Example 3, both of the films were lost in the initial stage, and the tissue change and peeling occurred. Further, in Comparative Examples 4 and 5, although the coating remained, linear peeling along the processing line occurred, and peeling occurred because of a large amount of hydrogen penetration. On the other hand, in Examples 1 to 3 of the present invention, linear peeling was observed, but the amount of invading hydrogen was remarkably smaller than that of the comparative example, and peeling did not occur. In particular, in Examples 4 and 5, the amount of invading hydrogen was very small, and excellent hydrogen suppression performance was shown.

  From the above, the high-strength sliding member of the present invention forms a hard film that hardly adheres to the mating member in sliding contact with the surface of the base material, and the hydrogen adsorbing substance is dispersed in the hard film. Alternatively, it was confirmed that by containing it in the state of a layer, hydrogen at the time of sliding was prevented from entering the base material and exhibited excellent strength.

  Next, in order to investigate the effect of the high-strength sliding member of the present invention, the same roller pitting test was performed on Examples 6 to 9 and Comparative Examples 6 to 10. For Examples 6 to 9 and Comparative Examples 6 to 10, JIS SCM420H was used for both the base material of the evaluation roller corresponding to the high-strength sliding member and the material of the mating roller that was in sliding contact therewith. Each roller has a surface hardness of Hv 740 by carburization, and then finished with a surface roughness Ra of 0.2 μm. Thereafter, the evaluation roller is washed with alkali, and a plurality of ion emission sources are used on the substrate surface. A hard film was formed by multi-target ion sputtering.

  In Examples 6 to 9, as shown in FIG. 2, a hard film 12 mainly composed of FeN is formed on the surface of the base material 11. At this time, a hydrogen diffusion inhibiting substance (hydrogen It is assumed that a hydrogen diffusion suppression layer 12a made of a suppression substance is provided, and each of the hydrogen diffusion suppression layers is Ni, W, Cd, and Cu.

  For Comparative Example 6, only the base material was used, and for Comparative Example 7, the base material surface was black-dyed in the same manner as in Comparative Example 2 above. In Comparative Example 8, a film made of CrN is formed on the surface of the substrate, and the film includes a hydrogen diffusion inhibiting layer made of Cd. In Comparative Examples 9 and 10, a film made of FeN is formed on the surface of the substrate. And the coating includes a hydrogen diffusion suppressing layer made of Al or Cr.

  The shape of the roller pitting test piece, the ion plating film forming conditions, and the roller pitting test conditions are the same as those in Examples 1 to 5 and Comparative Examples 1 to 5. Here, if the thickness of the hard film is too thin, the base material may be exposed when the shape of the member is complicated or the surface roughness is large. Since adhesion may be impaired, the thickness is preferably about 1 to 4 μm, and more preferably about 2 to 4 μm.

Then, for Example 6-9 and Comparative Example 6-10 performs roller pitting test until delamination evaluation roller reaches up to or 10 ⁷ cycles occurs, after the test, the residual situation and the releasing portion cross section of the hard film Tissue observation was performed. Moreover, the amount of hydrogen released from room temperature to 400 ° C. after the test was measured as the amount of hydrogen penetrating into the substrate. The results are shown in Table 2.

  As is apparent from Table 2, in Comparative Example 6, a hydrogen embrittlement-like structural change was observed, and peeling occurred in a short life. Moreover, in Comparative Example 7 and Comparative Example 8, both of the films were lost in the initial stage, resulting in a change in structure and peeling. Further, in Comparative Examples 9 and 10, although the coating remained, linear peeling along the processing line occurred, and peeling occurred due to a large amount of hydrogen penetration. On the other hand, in Examples 6 to 9 of the present invention, linear peeling was observed, but the amount of invading hydrogen was significantly smaller than that of the comparative example, and excellent hydrogen suppression performance was exhibited.

  From the above, the high-strength sliding member of the present invention forms a hard film that hardly adheres to the mating member that is in sliding contact with the base material surface, and the hard film is made of a hydrogen diffusion inhibitor. It was confirmed that by including the hydrogen diffusion inhibiting layer, the hydrogen at the time of sliding was prevented from entering the base material and exhibited excellent strength.

It is each sectional drawing (a)-(g) explaining the high intensity | strength sliding member of Examples 1-5 of this invention, and Comparative Examples 1-5. It is sectional drawing explaining the high intensity | strength sliding member of Examples 6-9 of this invention. It is sectional drawing explaining a roller pitting test apparatus. It is a structure | tissue photograph which shows the peeling part cross section which the hydrogen embrittlement-like structure | tissue change produced.

Explanation of symbols

1 11 Base material 2-4 4 Hard film 4b Hydrogen adsorption layer 12a Hydrogen diffusion suppression layer

Claims (11)

  A high-strength sliding member characterized in that a hard film that hardly adheres to a mating member that is in sliding contact is formed on the surface of a substrate, and the hard film contains a hydrogen-suppressing substance.   The high-strength sliding member according to claim 1, wherein the hydrogen-suppressing substance is a hydrogen-adsorbing substance having a function of adsorbing hydrogen, and the hydrogen-adsorbing substance is diffused in the hard film.   The hydrogen diffusing material is a hydrogen adsorbing material having a function of adsorbing hydrogen, and the hard film has a hydrogen adsorbing layer made of a hydrogen adsorbing material on the substrate side or in the film. 2. A high-strength sliding member according to 2.   The high-strength sliding member according to any one of claims 1 to 3, wherein the hard film is diamond-like carbon and does not contain a hydrogen suppressing substance between the outermost surface and a depth of at least 1 µm. .   The high-strength sliding member according to any one of claims 2 to 4, wherein the hydrogen-adsorbing substance is made of a material selected from Ni, Pd, Ti, Zr and a compound containing these metals.   2. The high-strength sliding material according to claim 1, wherein the hydrogen-suppressing substance is a hydrogen-diffusion-suppressing substance that suppresses hydrogen diffusion, and has a hydrogen-diffusion-suppressing layer made of a hydrogen-diffusion-suppressing substance in the hard film. Moving member. The base material is made of an iron-based alloy, the hard film is made of a metal having a Vickers hardness of 1000 or more, and the hydrogen diffusion inhibiting layer in the hard film is made of a metal or a compound thereof having a density of 8 g / cm ³ or more. The high-strength sliding member according to claim 6.   The high-strength sliding member according to claim 7, wherein the hard film is made of iron or an iron compound.   The high-strength sliding member according to any one of claims 6 to 8, wherein the hydrogen diffusion inhibitor is made of a material selected from Ni, Cd, Cu and W.   A method for producing a high-strength sliding member, comprising: forming a hard film by ion sputtering when producing the high-strength sliding member according to any one of claims 1 to 5. When manufacturing the high-strength sliding member according to any one of claims 1 and 6 to 9, a hard film is formed by an ion plating method or an ion sputtering method in which a temperature during film formation is 200 to 250 ° C. A manufacturing method of a high-strength sliding member characterized by the above.

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