JP2013210057A - Wear-resistant coat coating structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure that makes lubricant stored in a recess on a slide surface actively advance around the recess to improve lubricity and wear-resistance of the sliding surface.SOLUTION: A first bearing 1 in which a plurality of recesses 3 for storing lubricant supplied to a space 20 between a bearing sliding surface 1a and a rotation shaft sliding surface 4a that are mechanically faced are disposed on at least one side of the sliding surface, and a water repellent coat coating 5 which is formed as a film on the bearing sliding surface 1a, and advances the lubricant stored in the recesses 3 to a bank part around the recesses to accelerate lubrication on the sliding surface, are provided.

Description

  The present invention relates to a coating structure in which a contact surface of a base material with a mating member is coated with a wear-resistant coating.

For example, when sliding occurs on a relatively moving sliding surface such as a shaft and a bearing, or between a cylinder liner and a piston ring of an engine, the amount of wear exceeds a limit.
On the sliding surface, an oil film is formed on the contact surface using a lubrication device to reduce friction and reduce wear and heat generation.
However, there may be a case where the lubricating oil does not reach the sliding surface sufficiently due to structural problems, torsional deformation of the shaft, load fluctuations generated in the engine piston, and the like.
In this case, seizure between the sliding surfaces, abnormal wear, and the like may occur. In such a case, continuous use cannot be performed, and immediate replacement of the part is necessary.

JP-A-2000-35042 (Patent Document 1) exists as a prior art for dealing with such a case.
According to Patent Document 1, there is a technical disclosure in which a large number of minute depressions are arranged side by side on one or both contact surfaces of two solid bodies that perform relative motion, and lubricating oil is supplied into each of these depressions. It is made.

JP 2000-35042 A

However, in the structure according to Patent Document 1, there is a possibility that the depth of the recess (depth from the sliding surface) may disappear due to wear when the sliding surface is under high-pressure and high-speed sliding conditions.
Therefore, it is necessary to set an aspect ratio higher than an appropriate aspect ratio (depth / diameter).
In this case, since the depth of the concave portion is too deep in the initial use of the product, replacement of the lubricating oil in the concave portion does not occur, and a problem that the lubricating oil is deteriorated and the sliding performance of the sliding surface is deteriorated is assumed.

  Accordingly, the present invention has been made in view of such problems, and the lubricating oil stored in the concave portion of the sliding surface is actively advanced to the periphery of the concave portion, so that the lubricity and wear resistance of the sliding surface are increased. The object is to provide a structure that improves the above.

The present invention achieves such an object, and a substrate to be treated in which a plurality of recesses for storing lubricating oil supplied to mechanically opposed sliding surfaces are scattered and arranged on at least one side of the sliding surface;
Lubrication promoting film that is formed on the sliding surface of the substrate to be treated and advances the lubricating oil stored in the concave portion to the shore around the concave portion of the sliding surface to promote lubrication of the sliding surface. And.

  In this invention, since the lubrication promoting film is formed on the surface provided with the recess, the supplied lubricant is stored in the recess, and the lubricant in the reservoir is advanced to the sliding surface to supply the lubricant. It is possible to improve the wear resistance of the sliding surface by forming an oil film on the sliding surface of the shore around the recess at a portion where the lubricating oil from the portion is not directly applied.

  Preferably, in the present invention, the lubrication promoting coating is formed of an oil repellent material, and a surface due to surface tension when the lubricating oil is dropped onto the oil repellent material, and a coating surface of the oil repellent material, It is preferable that the contact angle formed by is 50 degrees or more.

  By adopting such a configuration, the oil repellent material has a physical contact angle with the lubricating oil of 50 degrees or more, so that the advance amount of the lubricating oil to the sliding surface is secured, and the sliding surface performance. Can be held.

  In the present invention, preferably, the recess has a hole diameter of 50 to 500 μm and a depth from the sliding surface of 50 to 150 μm.

By adopting such a configuration, by making the physical property of the lubrication promoting coating oil-repellent, the lubricating oil stored in the concave portion can be actively advanced from the concave portion to the sliding surface, and the hole diameter can be reduced to 50. By setting the depth to 50 to 150 μm, the storage amount of the lubricating oil increases, and the amount of contact with the opposing surface increases due to the bulging due to the surface tension of the lubricating oil, so that it advances to the sliding surface. The amount can also be increased.
Therefore, the wear resistance effect is great, and it has the effect of being able to cope with a portion with a large sliding surface load.

  In the present invention, preferably, the film of the oil repellent material is formed on at least the inner peripheral wall surface of the recess.

  With this configuration, since the oil-repellent substance is formed on the inner peripheral wall surface of the recess, the lubricating oil stored in the recess is easily discharged, the replacement of the lubricating oil in the recess is promoted, and the lubricating oil rises. Temperature and deterioration are prevented, and wear resistance of the sliding surface is improved.

  Preferably, in the present invention, the physical property of the lubrication promoting coating is formed by a lipophilic substance, and the surface by the surface tension when the lubricating oil is dropped on the lipophilic substance and the coating of the lipophilic substance. The contact angle formed by the surface is preferably 10 degrees or less.

  By adopting such a configuration, the oil repellent material has a physical contact angle with the lubricating oil of 10 degrees or less, so that the advance amount of the lubricating oil to the sliding surface is ensured, and the sliding surface performance. Can be held.

  In the present invention, preferably, the opening of the recess is 50 to 500 μm, and the depth from the sliding surface is 10 to 20 μm.

  By adopting such a configuration, by making the physical property of the lubrication promoting coating oleophilic, the lubricating oil stored in the concave portion can be actively advanced from the concave portion to the sliding surface, and further, the opening 50 can be opened. By setting the depth to 500 μm and the depth to 10 to 20 μm, the lubricant stored in the recesses can easily penetrate into the sliding surface, and the replacement of the lubricant in the recesses is promoted. Is prevented, and the wear resistance of the sliding surface is improved.

  In the present invention, preferably, the film of the lipophilic substance is formed at least around the opening edge of the recess.

  With such a configuration, a lipophilic substance is formed around the opening edge of the recess, so that the lubricating oil in the recess is positively applied to the so-called shore sliding surface where the sliding surface recess is not provided. Improve the wear resistance of the sliding part.

  In the present invention, the total area of the plurality of recesses formed on the sliding surface is preferably 5 to 50% with respect to the sliding area.

With such a configuration, when the surface pressure (load) acting on the sliding surface is large, the area ratio in which the recess is formed is increased, the amount of lubrication to the sliding surface is increased, and the sliding surface is increased. Ensure the lubricity of the moving surface.
On the other hand, when the surface pressure (load) is small, the area ratio in which the recesses are formed is reduced to reduce the processing costs for forming the recesses, and the lubricant supply amount is reduced to reduce the lubricant consumption (sliding). Outflow from moving parts to other parts) is reduced.

  According to the present invention, it is possible to improve the lubricity and wear resistance of the sliding surface by positively advancing the lubricating oil stored in the recessed portion provided on the sliding surface around the recess.

1 shows a schematic structural diagram of a bearing portion in which the present invention is implemented. When the oil-repellent film coating according to the first embodiment of the present invention is applied, (A) shows a partially enlarged view of FIG. 1M part, (B) shows an NN arrow view of (A), ( C) shows another oil-repellent coating coating example. In the case of the lipophilic film coating according to the second embodiment of the present invention, (A) shows a partially enlarged view of FIG. 1M part, (B) shows a PP arrow view of (A), ( C) shows another example of lipophilic film coating. The schematic structure figure when a lipophilic film coating is implemented to the ditch | groove which concerns on 3rd Embodiment of this invention is shown, (B) shows an example of the formation pattern of a ditch | groove, (C) shows another pattern. Show. The explanatory view of the contact angle of lubricating oil is shown.

Hereinafter, the present invention will be described in detail with reference to embodiments shown in the drawings.
However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to specific examples unless otherwise specifically described. Only.

(First embodiment)
FIG. 1 is a schematic structural view of a bearing portion in which the present invention is implemented.
The bearing structure includes a first bearing 1, a rotating shaft 4 fitted in a cylindrical portion having a circular cross section of the first bearing 1 around the axis of the cylindrical portion, and the rotation It is comprised with the oil pump 2 which pumps lubricating oil to the clearance gap (space part) of the axis | shaft 4 and a cylindrical part.
The first bearing 1 has a bearing member A, which is a substrate to be processed, in which the sliding surface 1a is formed in a semicircular shape, and a sliding surface 1b disposed so as to face the sliding surface 1a. The bearing member B, which is a substrate to be processed, is formed by a fastening bolt 24 that fastens the bearing member A and the bearing member B via a female screw 25 provided on the bearing member B.
In order to simplify the description, the sliding surface 1a and the sliding surface 1b are hereinafter collectively referred to as “bearing sliding surface 1c”.
Lubricating oil is supplied to the space 20 formed by the rotating shaft sliding surface 4a of the rotating shaft 4 and the bearing sliding surface 1c facing the rotating shaft sliding surface 4a, and a lubricating oil film is formed.
The lubricating oil film is pumped by the oil pump 2 to the space portion 20 via the first oil passage 15 provided in the bearing member B. The pumped lubricating oil circulates in the space 20 and is connected to the second oil passage 16 provided in the bearing member A and the second oil passage 16, and the third oil passage provided in the bearing member B. 17, the oil is returned to an oil tank (not shown) via the oil pump 2, and the lubricating oil is cooled in the oil tank.

FIG. 2 is a partially enlarged view of a portion M in FIG. 1. FIG. 2A shows a space portion 20 in which a lubricating oil film is formed between sliding surfaces where the first bearing 1 and the rotating shaft 4 face each other. Is formed.
A plurality of cylindrical recesses 3 are scattered and arranged on the bearing sliding surface 1c side.
The recess 3 is formed in a shape with a hole diameter D1 = 50 to 500 μm and a depth H1 = 50 to 150 μm from the bearing sliding surface 1 c to the bottom surface of the recess 3.
And the opening total area ratio of the recessed part with respect to the area of the whole sliding surface of the recessed part 3 (area of the bearing sliding surface 1c) was 5 to 50%.
When the total opening area ratio is <5%, the lubricating oil may not be sufficiently spread over the entire bearing sliding surface 1c, and it is difficult to obtain the effects of the present invention.
Further, when the total opening area ratio is greater than 50%, the surface pressure on the sliding surface other than the concave portion is increased, and it is difficult to obtain the effect of the present invention.
Further, the bearing sliding surface 1c including the inner peripheral wall surface 1b of the concave portion 3 is provided with an oil-repellent coating coating 5 which is provided with an oil-repellent PTFE (polytetrafluoroethylene) -containing Ni—P plating which is a lubrication promoting coating. A film is formed.
In this embodiment, PTFE-containing Ni is used as the oil-repellent coating, but in addition, a coating layer of PEEK (polyether ether ketone) or TiO ₂ (titanium oxide) may be formed, or silane coupling. A method of modifying the surface with a material may be used.

The reason why the hole diameter D1 of the concave portion 3 is 50 to 500 μm and the depth H1 to the bottom surface is H1 = 50 to 150 μm is that the amount of lubricating oil stored in the concave portion 3 advances to the periphery of the opening outer peripheral edge of the concave portion 3 Thus, the oil amount necessary for forming the oil film in the space portion 20 can be secured and the replacement of the stored lubricating oil can be promoted.
When the depth H1> 150 μm, the replacement of the lubricating oil is not sufficiently performed, and the temperature of the lubricating oil becomes high.
Therefore, the bearing sliding surface 1c and the rotating shaft sliding surface 4a can be cooled in accordance with the replacement of the lubricating oil, the deterioration of the lubricating oil can be prevented, and it can be applied to a portion that slides at a high speed and a high load. And the wear resistance of the sliding surface can be improved.
For example, good results have been obtained in a thrust bearing portion of a turbocharger.
Further, the hole diameter and depth of the recess 3 and the total opening area ratio of the recess are the rotational speed acting on the sliding portion (the bearing sliding surface 1c and the rotating shaft sliding surface 4a), the pressure acting on the sliding surface, etc. It may be set sequentially based on the use conditions.

Further, it has been found that if the oil repellent substance has an oil repellency with a contact angle θ ≧ 50 degrees in the shape of the recess 3, a hot water film in the sliding portion can be secured.
As shown in FIG. 5, the contact angle refers to the spherical surface and the oil repellency in the state where the lubricating oil is dropped on the oil repellent coating surface F and the lubricating oil occurs in a spherical shape on the oil repellent coating surface F. The angle formed between the tangent L of the spherical surface of the contact portion with the coating film surface F and the oil repellent coating film surface F is referred to as a contact angle.
The larger the contact angle, the higher the oil repellency.
The film thickness H2 of the oil-repellent film coating 5 was several μm (for example, 4 to 7 μm).
FIG. 2B is a view taken along the line NN (a plan view of the first bearing sliding surface 1a). The shore portion 3a and the concave portion 3 around the opening edge of the concave portion 3 of the bearing sliding surface 1c. An oil-repellent coating 5 is formed on the inner wall surface.
In addition, formation of the recessed part 3 can be easily performed by methods, such as a laser pulse or embossing and an etching.
Further, although the arrangement pattern of the recesses 3 is an orderly arrangement pattern in FIG. 2, the arrangement pattern is not defined as long as the distance between the adjacent recesses 3 becomes substantially equal.
Further, in the present embodiment, the concave portion 3 is formed only on the bearing sliding surface 1c side, but the same effect can be obtained by providing it on the rotating shaft sliding surface 4a side or on both surfaces.

With such a coating structure of the oil repellent material, the lubricating oil pumped by the oil pump 2 forms a lubricating oil film in the space portion 20 via the first oil passage 15, but the first oil passage 15 The portion close to is sufficiently supplied with lubricating oil, but the portion far from the first oil passage 15 has a portion where the hydraulic pressure decreases.
However, the lubricating oil is stored in the concave portion 3 by the supply of the lubricating oil from the oil pump 2 and the rotation of the rotating shaft 4, and the lubricating oil stored in the concave portion 3 is spherical due to the surface tension by the oil repellent coating 5. And flows out (advances) to the shore part which is the outer periphery of the opening edge of the recess 3 while being in contact with the rotating shaft sliding surface 4a, and an oil film is formed between the bearing sliding surface 1ca and the sliding surface Improves wear resistance.

  In this embodiment, in order to reduce the manufacturing cost, the oil repellent coating 5 is formed on the bearing sliding surface 1c (including the shore portion 3a around the opening edge of the recessed portion 3) and the inner wall surface of the recessed portion 3. However, as shown in FIG. 3C, if the oil repellent coating is applied to the inner peripheral wall 1b of the recess 3, the lubricating oil in the recess 3 is generated in a spherical shape by the surface tension, and is formed in the space portion 20. The same effect can be obtained because it is expanded.

(Second Embodiment)
Since this embodiment is the same as the first embodiment except that the material of the lubrication promoting coating changes from oil repellency to oleophilicity and the shape of the recess changes accordingly, the same parts are given the same reference numerals, Description is omitted.
FIG. 3A shows a partially enlarged view of the portion M in FIG. 1, and FIG. 3B shows a view taken along the line P-P in FIG. In addition, since the whole bearing part structure is the same as Embodiment 1, description is abbreviate | omitted.

In FIG. 3A, the sliding surfaces of the second bearing 6 and the rotary shaft 4 are opposed to each other through a space 20 in which a lubricating oil film is formed.
In order to simplify the description, hereinafter, the sliding surface of the bearing member A and the sliding surface of the bearing member B in FIG. 1 are collectively referred to as “bearing sliding surface 6a”.
A plurality of cylindrical concave portions 8 are scattered and arranged on the bearing sliding surface 6a of the bearing portion.
The recess 8 is formed in a shape with a hole diameter D2 = 50 to 500 μm and a depth H5 = 10 to 20 μm from the bearing sliding surface 6a.
And the opening total area ratio of the recessed part with respect to the area (bearing sliding surface 6a) of the whole sliding surface of the recessed part 8 was 5 to 50%.
Furthermore, the bearing sliding surface 6a including the inner peripheral wall surface 6b of the recess 8 uses a lipophilic silane coupling agent as a lubrication promoting coating.
As coupling agents, vinyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-acryloxypropyltrimethoxysilane, 3-aminopropyltriethoxysilane, etc. Can be used.

As described above, the recess 8 has a shape with a hole diameter D2 = 50 to 500 μm and a depth H5 = 10 to 20 μm to the bottom surface. The amount of the lubricating oil stored in the recess 8 is that the lubricant is in the recess 3. The shape advances to the shore portion 8a around the outer periphery of the opening to ensure the amount of oil necessary for forming an oil film in the space portion 20 and to facilitate replacement of the stored lubricating oil.
Further, by making the depth to the bottom surface H5 = 10 to 20 μm shallow (shallow than the oil-repellent coating), the lubricating oil stored in the concave portion 8 can be separated into the space portion 20 (lubricating oil film forming portion) by the affinity action of the lipophilic agent. ) Is easy to make a positive entry.
Therefore, the sliding surfaces (bearing sliding surface 6a and rotating shaft sliding surface 4a) can be cooled and the deterioration of the lubricating oil can be prevented with the replacement of the lubricating oil, and applied to the portion that slides at high speed and high load. And the wear resistance of the sliding surface can be improved.
For example, a good effect can be obtained in a compressor or an engine inside where lubricating oil tends to be insufficient.
Further, the hole diameter D2 and depth H5 of the recess 8 and the total opening area ratio of the recess may be sequentially set based on conditions such as the rotational speed acting on the sliding portion and the pressure acting on the sliding surface.

Further, if the lipophilic substance has a lipophilicity with a contact angle θ ≦ 10 degrees in the shape of the concave portion 8, the advance of the lubricating oil to the sliding portion is sufficiently promoted, and the resistance of the sliding portion is improved. It has been found that wear is improved.
As shown in FIG. 5, the contact angle refers to a hemispherical surface in a state where lubricating oil is dropped on the lipophilic coating coating surface F and the lubricating oil is generated in a hemispherical shape on the lipophilic coating coating surface G. An angle θ formed by the tangent L of the hemispherical surface of the contact portion with the lipophilic coating coating surface F and the lipophilic coating coating surface F is referred to as a contact angle.
The film thickness of the oleophilic coating 5 was several μm (for example, 4 to 7 μm).
FIG. 3 (B) shows a PP arrow view (plan view of the third bearing sliding surface 6a), and shows the recess 3 of the third and fourth bearing sliding surfaces 6a, 7a (see FIG. 1). The oil repellent coating 5 is formed on the shore around the opening edge and the inner wall surface of the recess 8.
In addition, formation of the recessed part 8 can be easily performed by methods, such as a laser pulse or an embossing.
The arrangement pattern of the recesses 8 is an orderly arrangement pattern in FIG. 3B, but the arrangement pattern is not defined if the distance between the adjacent recesses 3 becomes substantially equal.

With such a lipophilic material coating structure, the lubricating oil pumped by the oil pump 2 forms a lubricating oil film in the space 20 via the first oil passage 15. Lubricating oil is sufficiently supplied to the portion close to the passage 15, but a portion where the hydraulic pressure decreases is generated in a portion far from the first oil passage 15.
However, the lubricating oil stored in the concave portion is coated in an oleophilic coating and stored in the concave portion 8 by making the depth H5 = 10 to 20 μm from the bearing sliding surface 6a to the bottom surface (shallow than the oil-repellent coating). Thus, the lubricating oil can easily advance into the space portion 20 (lubricating oil film forming portion) by the affinity action of the lipophilic agent to improve the wear resistance of the sliding surface.

In this embodiment, the oil-repellent coating 5 is formed on the bearing sliding surface 6a (including the shore portion 8a around the opening edge of the recess 8) and the inner wall surface of the recess 8 in order to reduce the number of manufacturing steps. .
However, if the depth H5 to the bottom surface of the concave portion 3 is as shallow as 10 to 20 μm and the lipophilic film coating 9 is formed on the shore portion 8a on the outer periphery of the opening edge of the concave portion 8, the lubricating oil in the concave portion 8 is compatible. By virtue of the sexual effect, it is possible to advance into the space 20 and improve the wear resistance of the sliding surface.
Therefore, by implementing the lipophilic coating only on the outer peripheral edge of the opening periphery of the recess 3, the wear resistance of the sliding portion is improved and the amount of the lipophilic coating agent used is reduced to reduce the cost. You can also.

(Third embodiment)
This embodiment is the same as the second embodiment except that the shape of the concave portion is circular, except that the shape of the concave portion is a groove shape, and thus the same function is denoted by the same reference numeral and description thereof is omitted.

4A is a partially enlarged view of the bearing member A in FIG. 1M. The sliding surfaces of the third bearing 11, which is a non-treated base material, face each other through the space 20 where a lubricating oil film is formed.
In order to simplify the description of the structure of the third bearing 11, the sliding surface of the bearing member A and the sliding surface of the bearing member B shown in FIG. 1 are collectively referred to as “bearing sliding surface 11a”. Describe.
On the bearing sliding surface 11 a of the third bearing portion 11, a plurality of concave grooves 15 having a rectangular cross section, which is a concave portion, are arranged substantially in parallel with an interval.
The concave groove 15 is formed in a shape having a groove width W = 50 to 500 μm and a depth H5 = 10 to 20 μm from the bearing sliding surface 11a.
As shown in FIG. 4B, the groove 15 is inclined with an angle α with respect to the axis CL of the rotating shaft 4, and the groove 15 is formed on the entire bearing sliding surface (the bearing sliding surface 11a). The ratio of the total area of the openings of the concave grooves 15 to the area of
Furthermore, in this embodiment, only the bearing sliding surface 11a in the vicinity of the edge of the groove 15 is coated with a silane coupling agent (lipophilic coating coating 9) of a lipophilic substance that is a lubrication promoting coating.

  The reason why the lipophilic film coating 9 is only the sliding surface 11a in the vicinity of the edge of the groove 15 is that if the side wall of the groove 15 is also coated with the lipophilic film, the lubricating oil flowing into the groove 15 Lubricating oil that advances to the sliding surface 11 a in the vicinity of the edge of the groove 15 and lubricating oil that flows out along the groove 15 may be generated, and the amount of lubricating oil supplied to the space 20 may be insufficient.

  By forming the concave portion of the sliding portion into the shape of the concave groove 15, a lubricating oil passage is formed in the entire sliding portion, and the supply of lubricating oil from the oil pump 2 to the sliding surface is made uniform. In addition to the effect of the oleophilic coating coating, the temperature of the lubricating oil decreases due to the replacement of the lubricating oil, so that the viscosity of the lubricating oil is maintained by cooling the sliding portion. As a result, the wear resistance of the sliding portion is improved, and the durability of the high-speed sliding and high-load bearing portion is improved.

4C is a crossing of the groove 15 inclined at an angle β with respect to the axis CL of the rotating shaft 4 with respect to FIG. 4B. The same except for changing the pattern.
By using such an arrangement pattern of the grooves 15 in an apparatus in which the rotating shaft 4 rotates forward and backward, in addition to the effect of the oleophilic coating, to the space due to the viscosity of the rotating shaft 4 and the lubricating oil. As a result, the wear resistance of the sliding part is improved, the sliding resistance is reduced, the sliding speed is high, and the durability of the bearing is increased.

  The present invention can be applied to a coating structure in which a contact surface of a substrate with a mating member is coated with a wear resistant member.

1 First bearing (clothing substrate)
1c, 6a, 11a Bearing sliding surface 3, 8, 15 Recess 4 Rotating shaft 4a Rotating shaft sliding surface 5 Oil-repellent coating (lubrication promoting coating)
6 Second bearing (clothing substrate)
9 Lipophilic coating (Lubrication promotion coating)
11 Third bearing (clothing substrate)
20 Space part (lubricating oil film forming part)
CL axis of rotation axis D1, D2 hole diameter H1 recess depth H2 film thickness

Claims (8)

A substrate to be treated in which a plurality of recesses for storing lubricating oil supplied to mechanically opposed sliding surfaces are scattered and disposed on at least one side of the sliding surface;
Lubrication promoting film that is formed on the sliding surface of the substrate to be treated and advances the lubricating oil stored in the concave portion to the shore around the concave portion of the sliding surface to promote lubrication of the sliding surface. And a wear-resistant coating structure characterized by comprising:   The lubrication promoting coating is formed of an oil repellent material, and a contact angle formed by a surface tension when the lubricating oil is dropped on the oil repellent material and a coating surface of the oil repellent material is 50 degrees or more. The wear-resistant coating film structure according to claim 1, wherein   The wear resistant coating structure according to claim 1 or 2, wherein a hole diameter of the concave portion is 50 to 500 µm, and a depth from the sliding surface is 50 to 150 µm.   4. The wear-resistant coating structure according to claim 2, wherein the coating of the oil repellent material is formed on at least an inner peripheral wall surface of the recess.   The physical property of the lubrication promoting coating is formed by a lipophilic substance, and the contact angle formed by the surface due to the surface tension when the lubricating oil is dropped on the lipophilic substance and the coating surface of the lipophilic substance is 10 The wear-resistant coating film structure according to claim 1, wherein the wear-resistant film coating structure is less than or equal to a degree.   6. The wear-resistant coating film structure according to claim 1, wherein the opening of the recess is 50 to 500 [mu] m and the depth from the sliding surface is 10 to 20 [mu] m.   The wear-resistant film coating structure according to claim 5 or 6, wherein the film of the lipophilic substance is formed at least around the opening edge of the recess. The wear resistance according to any one of claims 1 to 7, wherein a total area of the plurality of concave portions formed on the sliding surface is 5 to 50% of the sliding area. Film coating structure.

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