JP6540950B2 - Sliding member, method of manufacturing sliding member and power transmission device - Google Patents

Description

The present invention relates to a sliding member, a method of manufacturing the sliding member, and a power transmission device.
More particularly, the present invention relates to a sliding member having high durability and suitable for a power transmission device, a method of manufacturing the same, and a power transmission device equipped with a sliding member having high durability.

  The sliding members used in places that rotate and slide, such as bearings, gears, cams, universal joints, rolls, rings, etc., are required to have wear resistance, and surface hardness is being increased. .

  Among the sliding members, in particular, the sliding members used in the power transmission device contact the members with a very high surface pressure and transmit the driving force, and therefore the sliding deformation resistance is required. Otherwise, if the elastic deformation is not caused by the contact, the contact pressure at the contact point is not reduced and the durability is lowered. Therefore, there is a limit to the improvement of the durability by using a high hardness material having a high Young's modulus.

In Patent Document 1, a power transmission having a durability improved by reducing the equivalent Young's modulus of the entire member by forming a film having a Young's modulus of 250 GPa or more on the surface of a metal base having a Young's modulus of 220 GPa or less. A sliding member for a device is disclosed.

International Publication 2013/005764

  Although the sliding member for a power transmission device described in Patent Document 1 is excellent in durability, it is desirable to further improve the durability due to demands for smaller size and weight of the power transmission device itself and higher output of an engine. Be

  The present invention has been made in view of the problems of the prior art, and the object of the present invention is to provide a sliding member having excellent durability, a method of manufacturing the same, and a sliding having excellent durability. An object of the present invention is to provide a power transmission device having a member.

  The present inventors diligently studied to achieve the above object. As a result, it has been found that not only the Young's modulus of the film is increased, but also the sliding deformation is prevented and the durability of the sliding member can be dramatically improved by the presence of hard particles of the desired particle diameter in the film. The present invention has been completed.

That is, the sliding member of the present invention has a film containing hard particles and a metal material and having a Young's modulus of 250 Gpa or more, and the hard particles are at least one selected from carbides, borides or oxides. The area ratio of the hard particles in the cross-sectional area of the film is 50% or more and 70% or less, and the area ratio of the hard particles in the equivalent particle diameter of 1.2 μm to 5 μm among the hard particles is 3 % Or more and 30% or less , and the cross-sectional porosity of the film is 1.1% or less by volume .

  Further, in the power transmission device of the present invention, a plurality of sliding members come into contact to transmit power, and the sliding member of the present invention is provided.

  Furthermore, the method for manufacturing a sliding member for a power transmission device according to the present invention is a method for manufacturing the sliding member according to the present invention, wherein a powder containing hard particles and a metal material is heated to To form a film.

  According to the present invention, hard particles are contained in a film having a Young's modulus of 250 Gpa or more, and among the hard particles, the area ratio of hard particles having an equivalent circular diameter of 1.2 μm to 5 μm is 3% or more. Therefore, it is possible to achieve both slip resistance and elastic deformation, and a sliding member having a strong and hard film and excellent in durability, a method of manufacturing the sliding member, and a power transmission device equipped with the sliding member. Is provided.

It is a figure which shows an example of the film | membrane structure of the sliding member of this invention. It is a graph which shows the example of the relationship between the area ratio of the hard particle in a film, and the seizing limit temperature. It is a figure showing an example of the power transmission device of the present invention. It is the front view and side view which show the point of the endurance test.

  The sliding member, the method of manufacturing the sliding member, and the power transmission device of the present invention will be described in detail. The sliding member of the present invention has a film on the surface of a metal substrate.

<Coating>
The coating of the present invention comprises hard particles and a metal material. An example of the structure of the film | membrane in the sliding member of this invention is shown in FIG. The sliding member 1 of the present invention has a coating 4 on a metal base 2. The film 4 has a structure in which hard particles 4a are dispersed in a metal material 4b.
Among hard particles in the film, the area ratio of the hard particles having an equivalent circle diameter of 1.2 μm to 5 μm in the film cross section is 3% or more, and the Young's modulus is 250 Gpa or more.
The film 4 may include holes (not shown).

As the hard particles 4a, those having a hardness higher than that of the metal substrate 2 as a base and having a melting point higher than that of the metal substrate 2 can be used. For example, carbides, borides, Hard particles of nitride and oxide can be mentioned.
The seizure resistance can be improved by using hard particles having high hardness and high melting point.

As hard particles of carbide, for example, titanium carbide (TiC), zirconium carbide (ZrC), vanadium carbide (VC), niobium carbide (NbC), tantalum carbide (TaC), chromium carbide (Cr ₃ C ₂ ), molybdenum carbide Hard particles such as (Mo ₂ C), tungsten carbide (WC), boron carbide (B ₄ C), silicon carbide (SiC) and the like can be mentioned.

As hard particles of borides, for example, titanium boride (TiB ₂ ), zirconium boride (ZrB ₂ ), vanadium boride (VB ₂ ), niobium boride (NbB ₂ ), tantalum boride (TaB ₂ ), Chromium boride (CrB ₂ ), molybdenum boride (Mo ₂ B ₅ ), tungsten boride (W ₂ B ₅ ), boron (B), aluminum boride (AlB ₁₂ ), silicon boride (SiB ₆ ), etc. Hard particles can be mentioned.

Examples of hard nitride particles include titanium nitride (TiN), zirconium nitride (ZrN), vanadium nitride (VN), niobium nitride (NbN), chromium nitride (CrN), boron nitride (c-BN), and silicon nitride (c Hard particles made of Si ₃ N ₄ ), aluminum nitride (AlN) or the like can be mentioned.

As hard particles of oxide, for example, aluminum oxide (Al ₂ O ₃ ), zirconium oxide (ZrO ₂ ), silicon oxide (SiO ₂ ), titanium oxide (TiO ₂ ), thorium oxide (ThO ₂ ), beryllium oxide (BeO) And hard particles made of magnesium oxide (MgO) or the like.
Magnesium oxide is preferably contained, for example, as magnesium zirconate.

These hard particles may be used alone or in combination of two or more.
Among them, tungsten carbide (WC) has a high hardness (Vickers hardness: 2350 HV) and a high melting point (melting point: 2776 ° C.) and can form a film of high hardness and has a high density (15.72 g / cm ³ ). When forming a film by the thermal spraying method, since a precise | minute film | membrane with few holes can be formed, it can use preferably.

<Metal material>
The metal material 4b wraps the hard particles 4a to form the inside 4 of the film together with the hard particles 4a, and plastically deforms appropriately when sprayed onto a metal substrate, and is applied to the surface of the metal substrate 2 It is sufficient that a dense film can be formed, and a single metal or an alloy can be used.

  As a metal single-piece | unit, cobalt (Co), iron (Fe), titanium (Ti) etc. can be mentioned, for example.

  Further, as the alloy, for example, cobalt (Co) -chromium (Cr), nickel (Ni) -chromium (Cr), Hastelloy (registered trademark), chromium (Cr) -molybdenum (Mo), tungsten (W) )-Chromium (Cr), Nickel (Ni)-Cobalt (Co)-Chromium (Cr), Tungsten (W)-Cobalt (Co), Nickel (Ni)-Chromium (Cr)-Aluminum (Al), Nickel (Ni) ) -Molybdenum (Mo) etc., which may be intermetallic compounds or solid solutions

  Although these may be used individually or in combination of 2 or more types, cobalt (Co) is easy to be plastically deformed among them, and since it is easy to form a precise film, it can be used preferably.

<Spray material>
The hard particles and the metal material are mixed and used as a thermal spray material obtained by granulating or sintering a mixture thereof. It is preferable that content of the metal material in the said thermal spray material is 12 mass%-17 mass%.
If the content is less than 12% by mass, the area ratio of the metal material such as cobalt serving as a binder decreases, so that the hard particles may be easily detached from the film. If the content exceeds 17% by mass, the proportion of hard particles is decreased. Sex may decrease.

In order to form a dense film with a low porosity by the thermal spraying method, the particle velocity needs to be 700 m / sec or more, and the collision with the metal base causes the hard particles to break.
Therefore, the average primary particle diameter of the hard particles in the thermal spray material is preferably 2 μm or more and 5 μm or less.

If the average primary particle diameter of hard particles in the thermal spray material is less than 2 μm, it is difficult to make the area ratio of hard particles having an equivalent circular diameter of 1.2 μm to 5 μm in the coating 3% or more.
In addition, when the average primary particle diameter of hard particles in the thermal spray material exceeds 5 μm, the particle diameter of the hard particles in the coating becomes large, the aggressivity to the contacting counterpart increases, and the wear resistance decreases. In some cases, the particle size of the thermal spray material becomes large, the collision velocity becomes slow, and the pores of the film become large or the film hardness decreases.

  The particle diameter of the thermal spray material is preferably 15 μm or more and 25 μm or less. If it is less than 15 μm, it will be difficult to sufficiently contain hard particles having a desired particle diameter, and if it exceeds 25 μm, it will be difficult to increase the particle velocity when spraying, and pores in the film may be increased.

<Area ratio of hard particles>
In the film of the present invention, the area ratio of the hard particles having an equivalent circle diameter of 1.2 μm to 5 μm in the film cross section is 3% or more, and the upper limit thereof is preferably 30% or less. It is preferable that it is% or less.

Hard particles having an equivalent circular diameter of less than 1.2 μm do not contribute to the prevention of sliding deformation, and particles exceeding 5 μm have high aggressivity on the other member and lower durability.
If the area ratio is less than 3%, the seizure resistance may be reduced, and if the area ratio exceeds 30%, the productivity may be reduced.

Here, the relationship between the area ratio of the equivalent circle diameter of 1.2 μm to 5 μm and the burn-in limit temperature is shown in FIG.
As shown in FIG. 2, the seizure limit temperature increases as the area ratio of the equivalent circle diameter of 1.2 μm to 5 μm increases, and hard particles of the equivalent circle diameter of 1.2 μm to 5 μm improve the seizure resistance. It is understood that it contributes to
In the present invention, "equivalent circle diameter" refers to the diameter of a circle having the same area as the area of the hard particles to be observed.

  The area ratio of the hard particles in the film was determined by cutting the sliding member, photographing the cross section using a scanning microscope, and making the metal material such as cobalt observed in gray the same as the holes and making it black by the binarization treatment. , Hard particles are extracted as white parts. It can measure by integrating | accumulating the area of the hard particle | grains which become equivalent 1.2 micrometers-5 micrometers in a measurement area.

  Moreover, it is preferable that the area ratio for which all the hard particles in a film occupy to a film | membrane cross section is 50% or more and 70% or less. When the porosity is 50% or more and 70% or less, a dense film is formed with a low porosity, and the detachment of hard particles from the film is prevented.

<Sectional porosity of film>
The cross-sectional porosity of the film of the present invention is preferably 1.1% or less.
When the cross-sectional porosity of the film exceeds 1.1% by volume, asperities are easily generated on the surface of the sliding member, and stress is concentrated on the asperities to be a starting point of sliding deformation, so that the mechanical strength decreases. And can not withstand repeated use under high loads.

The cross-sectional porosity of the film changes depending on the heating temperature and the spraying speed when the thermal spray material is sprayed onto the surface of the metal substrate. The heating temperature is preferably 800 ° C. or more and 1200 ° C. or less, although it depends on the type of the sprayed material to be sprayed and the spraying speed. When the heating temperature is high, the film may be porous to increase the porosity, and when the heating temperature is low, the film strength may not be obtained.
Further, the particle velocity at the time of spraying is preferably 700 m / s or more and 1100 m / s or less although it depends on the material to be sprayed and the heating temperature. If it is less than 700 m / s, the porosity may increase, and if it exceeds 1100 m / s, the hard particles may be broken, the hard particles in the film may be reduced in particle size, and the durability may be lowered.

The cross-sectional porosity of the film is obtained by cutting the sliding member, taking an image of the cross-section using a scanning microscope, capturing the image into an image processing device, and binarizing the sky as the measurement object The holes are extracted as black parts. And it can measure by calculating the area ratio of the black part observed using an image-analysis apparatus (Carl Zeiss AxioVision).

<Young's modulus of film>
The Young's modulus of the film of the present invention is 250 GPa or more, and more preferably 260 GPa to 510 GPa.
Since the film of the present invention is excellent in sliding deformation resistance and wear resistance, the thickness of the film can be reduced, and even if the Young's modulus is relatively high, the influence on the equivalent Young's modulus of the sliding member can be reduced. The stress on the part can be reduced.

  With such a configuration, the sliding member has excellent durability even under high surface pressure, for example, of about 3.5 GPa. Therefore, the present invention can be suitably used in a power transmission apparatus such as a multi-stage transmission using a traction drive having a structure in which a sliding member has a clutch mechanism or a transfer of a four-wheel drive vehicle.

The Young's modulus of the film was obtained by cutting the sliding member and fixing it on the stage of a micro indenter (Nano Indenter XP made by MTS Systems), using an indenter (Berkovich (triangular pyramid)), measuring the rigidity five times Go and get data.
The analysis can be performed by analyzing the obtained data under the analysis condition that the Young's modulus is calculated by a numerical value at a contact depth of about 800 nm.

The equivalent Young's modulus of the sliding member is determined by the following equation (1), with the Poisson's ratio of the film being 0.3, from the Young's modulus and Poisson's ratio of the metal base and the Young's modulus and Poisson's ratio of the film The equivalent Young's modulus (E *) of the sliding member can be calculated.
In the parameters (1) and (2) of the following equation (1), since α, E and H have a constant relationship, they can be plotted and calculated by curve fitting.

<Hardness of film>
The Vickers hardness of the film of the present invention is preferably 1000 HV or more and 1400 Hv or less.
If it is less than 1000 HV, the abrasion resistance may be low and the durability may be reduced.
Coating hardness can measure surface hardness (Hv) by load: 50 g using a micro Vickers hardness tester.

<Thickness of film>
The thickness of the film is preferably 5 μm or more and 600 μm or less, and more preferably 50 μm or more and 500 μm. Since the film of the present invention is hard and excellent in durability, sufficient durability of the sliding member can be imparted even if the film is made thin.
If it is less than 5 μm, hard particles may not be present sufficiently and durability may be lowered. If it exceeds 600 μm, the Young's modulus of the film has a great influence on the equivalent Young's modulus of the sliding member, and the elastic deformation of the sliding member As a result, the contact pressure at the contact portion may increase and the durability may decrease.

Moreover, it is preferable that the said film contains many hard particles with an equivalent circular diameter of 1.2 micrometers-5 micrometers in the surface side rather than the metal base material side. Specifically, when the film is divided into two in the thickness direction, the area ratio of hard particles of the above particle size on the metal substrate side is 3% or more and 12% or less, and hard particles of the above particle size on the surface side The area ratio of is preferably 15% or more and 30% or less.
The presence of a large amount of metal material on the side of the metal base makes it difficult to peel off the film, and the inclusion of a large amount of hard particles on the surface side improves the seizure resistance. In addition, the cooling time for preventing the softening and deformation of the metal base at the time of film formation is shortened, and the productivity is improved.

  The area ratio of the hard particles having the above-described particle size can be changed by changing the type of powder containing the hard particles and the metal material and the spraying conditions a plurality of times.

<Metal base material>
As a metal base material, what is used as a base material of the conventional sliding member can be applied, and that whose Young's modulus is 140 GPa or more and 250 GPa or less is preferable.
When the Young's modulus is 250 GPa or less, in conjunction with the above film, the equivalent Young's modulus of the sliding member can be made 250 GPa or more to 350 GPa, the contact pressure at the contact portion is reduced, and the durability can be improved.

As such a metal base material, for example, JIS G4051 carbon steel material for machine structure (SC) standardized by Japanese Industrial Standard (JIS), structural steel material for structural use (H steel) which is quenched by JIS G4052, JIS G4053 Structural alloy steels (manganese steel (SMn), manganese chromium steel (SMnC), chromium steel (SCr), chromium molybdenum steel (SCM), nickel chromium steel (SNC), nickel chromium molybdenum steel (SNCM)), JIS G4401 carbon Tool steel materials (SK), JIS G4403 high speed steel materials (SKH), JIS G4404 alloy tool steel materials (SKS, SKD, SKT), JIS G4805 high carbon chromium bearing steel materials (SUJ), JIS G5502 spheroidal graphite cast iron (FCD) And the like can be mentioned.
Typically, the hardness is about 700 to 800 HV, and the melting point is about 1400 to 1500 ° C.

<Method of manufacturing sliding member>
Next, the method of manufacturing the sliding member of the present invention will be described in detail.
The method for producing a sliding member according to the present invention is a method for producing the sliding member according to the present invention, wherein a powder containing hard particles and a metal material is heated and sprayed on the surface of a metal base to form a film. It is a thing. Specifically, the film in the present invention can be formed by spraying at high speed particles (a thermal spray material) containing hard particles having a large primary particle diameter and a metal material.
In addition, although the method of heating and spraying a thermal spray material and forming a film in general is called a thermal spraying method, if a thermal spraying material is heated with the thermal spraying method in this invention, a thermal spraying material will melt completely. Does not mean that

  By using the above thermal spraying method, it is possible to spray a thermal spray material having a particle diameter of several μm to several tens of μm on the surface of a metal base, facilitating the operation of forming a film, thickness of the film and hard particles in the film. The distribution state can be changed, and a sliding member excellent in durability can be manufactured at low cost.

Moreover, it is preferable to perform the said thermal spraying method in air | atmosphere. By forming the film in the atmosphere, it can be easily applied to the production of a large sliding member.
Needless to say, it can be performed not only in the atmosphere but also under conditions where the atmosphere is controlled.

  Further, the thermal spraying method is preferably, for example, a high speed flame spraying method. High speed flame spraying methods include HVOF (High Velocity Oxy-Fuel) using oxygen as a support gas and HVAF (High Velocity Air Fuel) using air as a support gas.

  In the present invention, the cross-sectional porosity of the film is 5% or less, and in order to form such a dense film with few holes, it is important to increase the particle velocity. It is preferable to apply

  Since the HVOF uses most of the auxiliary gas for gas combustion, the temperature of the combustion gas becomes high. On the other hand, in HVAF, since the auxiliary gas is air, 80% of components other than oxygen are not used for combustion. Therefore, the combustion gas can be cooled, and the combustion gas temperature can be lowered.

  In addition, when the temperature of the combustion gas is high, the thermal spray material easily adheres to the inside of the nozzle, so it is difficult to use the Laval nozzle to increase the particle velocity in the HVOF. On the other hand, in the HVAF, since the combustion gas temperature is low, a Laval nozzle can be used to increase the particle velocity. In addition, since a large amount of gas other than oxygen which is not used for combustion flows through the nozzle as a carrier gas of the thermal spray material, it is possible to make the particle velocity faster than HVOF without using a Laval nozzle.

<Power transmission device>
Next, the power transmission device of the present invention will be described in detail with reference to the drawings.
FIG. 4 is a cross-sectional view showing a transfer of a four-wheel drive vehicle which is an example of the power transmission device of the present invention.
In a transfer 100 of a four-wheel drive vehicle shown in FIG. 4, an input shaft 10 and an output shaft 20 which are examples of sliding members are disposed in a housing H.
The input shaft 10 is rotatably supported by the ball bearings 31 and 32 with respect to the housing H, and the output shaft 20 is also rotatably supported by the ball bearings 33 and 34 with respect to the housing H.
The input shaft 10 is further rotatably supported relative to the housing H by roller bearings 35, 36 disposed in the housing H, and roller bearings 37, 38 in which the output shaft 20 is also disposed in the housing H. Is also rotatably supported with respect to the housing H.

The roller bearing 35 for supporting the input shaft 10 and 37 for supporting the output shaft 20 are held within a common bearing support 39, and the bearing support 39 can be the corresponding inner side of the housing H by any means such as bolts 40 or the like. Attach to
Further, the roller bearing 36 for supporting the input shaft 10 and the member 38 for supporting the output shaft 20 are held in a common bearing support 41, and the bearing support 41 is supported by the housing H by any means such as a bolt 42 or the like. Attach to the inside surface.

Both ends of the input shaft 10 are respectively projected from the housing H, the left end in the figure of the input shaft 10 is connected to the output shaft of a transmission (not shown), and the right end in the figure is a rear propeller shaft (not shown). ) To the rear final drive unit (not shown).
The left end of the output shaft 20 in the figure protrudes from the housing H, and the protruding left end of the output shaft 20 is coupled to a front final drive unit (not shown) via a front propeller shaft (not shown).

The input shaft 10 is formed of high carbon chromium bearing steel (SUJ2), and has a first roller 11 formed of high carbon chromium bearing steel (SUJ2) in the axial direction and on its surface, It has the WC-Co coating 12 of the present invention formed by the high speed flame spraying method.
The output shaft 20 is also formed of high carbon chromium bearing steel (SUJ2), and has a second roller 21 formed of high carbon chromium bearing steel (SUJ2) in the axial direction and on the surface thereof Is formed with the WC-Co coating 22 of the present invention formed by high-speed flame spraying.

The first roller 11 and the second roller 21 are disposed in a common plane.
Then, the first roller 11 and the second roller 21 are pressed against each other, and the films on the outer peripheral surface of the roller are brought into pressure contact with each other at the portions indicated by reference numerals 12a and 22a under pre-pressure.

That is, the bearing supports 39 and 41 set the distance between the axes of the first roller 11 and the second roller 21 smaller than the sum of the radius of the first roller 11 and the radius of the second roller 21. A pressing force is generated between the roller 11 and the second roller 21.
The torque that can be transmitted between the first roller 11 and the second roller 21 is determined by this pressing force.
In addition, in FIG. 4, although the film | membranes 12 and 22 are formed in both the 1st roller 11 and the 2nd roller 21, when durability can be satisfied, you may form a film only in any one. (Not shown).

In the transfer 100, for example, when the rear wheel is slippery and the front wheel is not slippery, the input shaft 10 is rotated and the output shaft 20 is not rotated.
At this time, the driving force is transmitted to the output shaft 20 by pressing the first rotor 11 of the input shaft 10 and the second rotor 21 of the output shaft 20 in order to drive the vehicle.
At this time, since the output shaft 20 is not rotating, the driving force is transmitted with a large sliding speed by being pressed.
And in the transfer which applied the sliding member of this invention, since a predetermined | prescribed film | membrane is formed, durability becomes high. In addition, it is possible to sufficiently transmit the driving force by suppressing or preventing the occurrence of the burn-in.

  At this time, the sliding members of the first roller 11 and the second roller 21 may be in contact with each other via a lubricant or may be in direct contact (not shown). As a lubricant, typically, traction oil (KTF-1) can be used.

  Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited to the following examples.

Example 1
Thermal spray material (composition: WC-12 mass% Co, SWC-12A, manufactured by Sumitomo Mining Co., Ltd.) containing tungsten carbide (WC) having a primary particle diameter of 2 μm as hard particles and cobalt (Co) as a metal material The resultant was sieved to obtain a thermal spray material having a particle size D50 of 16.80 μm.
Against the surface of a metallic substrate (Young's modulus: 208 GPa, Poisson's ratio: 0.3, surface hardness: 700 to 750 HV, shape: cylinder (OD 70 mm, width 18 mm)) made of high carbon chromium bearing steel (SUJ2) And blasted using aluminum oxide particles.
The sprayed material is sprayed on the surface of a metal base by high-speed flame spraying under the following conditions, and the surface of the film is ground with a diamond wheel and then lapped with a surface roughness Ra of 0.04 μm or less using diamond abrasive grains. Thus, a [sliding member 1] having a coating thickness of 100 μm was obtained.

[High-speed flame spraying conditions]
Auxiliary gas: Air
Use of rubber nozzle: Yes Heating temperature: 1000 ° C
Particle velocity: 1000 m / s
Spray distance: 300 mm

For particle velocity, visualize particle velocity at spray distance (distance from nozzle tip to substrate) Using an image velocimeter (PIV: Particle Image Velocimetry), from the nozzle tip without setting the metal substrate Spray distance The flying speed of the particles at the separated position was measured to obtain the particle speed.

Example 2
[Sliding member 2] was obtained in the same manner as Example 1 except that the film thickness was changed to 500 μm.

[Example 3]
A [sliding member 3] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
(30/5 mesh) of a thermal spray material (composition: WC-12 mass% Co, AIMPERIT 519.059 containing tungsten carbide (WC) having a primary particle diameter of 1 μm as hard particles and cobalt (Co) as a metal material , H. C. STARCK company)

Example 4
A [sliding member 4] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray material (composition: WC-12 mass% Co, R13-025) containing (32/5 mesh) tungsten carbide (WC) having a primary particle size of 5.0 μm as hard particles and cobalt (Co) as a metal material , Paul Rex)

[Example 5]
A [sliding member 5] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spraying material (composition: WC-30 mass% Co, R13- (32/5 mesh) containing tungsten carbide (WC) having a primary particle size of 5.0 μm as hard particles and cobalt (Co) as a metal material 026, made by Paulex

[Example 6]
[Sliding member 6] was obtained in the same manner as in Example 1 except that the film thickness was changed to 50 μm.

[Example 7]
A [sliding member 7] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray material (composition: WC-12 mass% Co, SCS-) having a particle diameter D50 of 21.65 μm containing tungsten carbide (WC) having a primary particle diameter of 5 μm as hard particles and cobalt (Co) as a metal material 23, made by Paulex

[Example 8]
A [sliding member 8] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
(32/5 mesh) thermal spray material (composition: WC-12 mass% Co, R13- containing tungsten carbide (WC) having a primary particle diameter of 2.0 μm as hard particles and cobalt (Co) as a metal material 022, made by Paulex

[Example 9]
A [sliding member 9] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray material (composition: WC-12 mass% Co, AIMPERIT 518.) having a particle diameter D50 of 17.94 μm containing tungsten carbide (WC) having a primary particle diameter of 2 μm as hard particles and cobalt (Co) as a metal material. 059, manufactured by HC STARCK

[Example 10]
A [sliding member 10] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
(32/5 mesh) thermal spray material (composition: WC-12 mass% Co, R13- containing tungsten carbide (WC) having a primary particle diameter of 2.5 μm as hard particles and cobalt (Co) as a metal material 023, made by Paulex

Comparative Example 1
A [sliding member 11] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray containing tungsten carbide (WC) having a primary particle size of 1 μm as hard particles, chromium carbide (CrC) having a primary particle size of 1 μm, and nickel (Ni) as a metal material and having a particle size D50 of 18.82 μm Material (Composition: 73% by mass WC-20% by mass CrC-7% by mass Ni, AIMPERIT 551.059, manufactured by H. C. STARCK)

Comparative Example 2
A [sliding member 12] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray material (composition: WC-17 mass% Co) having a particle diameter D50 of 18.82 μm containing tungsten carbide (WC) having a primary particle diameter of 2.5 μm as hard particles and cobalt (Co) as a metal material AIMPERIT 526.059, manufactured by H. C. STARCK)

Comparative Example 3
A [sliding member 13] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray material (composition: 86 mass% WC—with a particle diameter D50 of 19.06 μm, containing tungsten carbide (WC) having a primary particle diameter of 2 μm as hard particles and cobalt (Co) chromium (Cr) as a metal material 10% by mass Co-4% by mass Cr, SWCC-14A, manufactured by Sumitomo Mining Co., Ltd.

Comparative Example 4
A [sliding member 14] having a coating thickness of 100 μm was obtained in the same manner as in Example 1 except that the thermal spray material was changed to the following.
Thermal spray material (composition: WC-12 mass% Co) having a particle diameter D50 of 16.83 μm containing tungsten carbide (WC) having a primary particle diameter of 0.2 μm as hard particles and cobalt (Co) as a metal material W661, manufactured by Fujimi Corporation

[Performance evaluation]
(Durability evaluation test)
FIG. 5A and FIG. 5B are a front view and a side view showing a point of a durability evaluation test.
As shown in the figure, flat-shaped [sliding members 1 to 10] were arranged to be in contact with the outer peripheral portion of the R10-shaped roller 5 in which a hard film was formed on SUJ 2.
Then, the roller 1 and the roller 5 are rotated while supplying the lubricant (traction oil) 7 from the lubricant supply device 6 under the conditions shown in Table 1 below, and the roller 1 is vibrated by the vibration generated by the occurrence of pitching. The number of revolutions until the roller stopped was determined to evaluate the durability of the roller 1. The evaluation results are shown in Table 2.

Reference Signs List 1 sliding member 2 metal base 4 coating 4a hard particle 4b metal material 5 roller 6 lubricant supply device 7 lubricant 10 input shaft 11 first roller 12, 22 coating 20 output shaft 21 second roller 31, 32, 33 34 ball bearings 35, 36, 37, 38 Roller bearings 39, 41 Bearing supports 40, 42 bolts 100 Transfer H housing of four-wheel drive vehicle

Claims (10)

A sliding member having a film on the surface of a metal substrate,
The film contains hard particles and a metal material, and has a Young's modulus of 250 Gpa or more.
The hard particles are one or more selected from carbides, borides or oxides,
The area ratio of the hard particles in the film cross section is 50% to 70%, and the area ratio of the hard particles having an equivalent circle diameter of 1.2 μm to 5 μm is 30 % to 30 %. % Or less ,
A sliding member characterized in that a cross-sectional porosity of the film is 1.1% by volume or less .  2. The sliding member according to claim 1, wherein the film contains a large number of hard particles with an equivalent circular diameter of 1.2 μm to 5 μm on the surface side of the metal base side. 3.   A sliding member having a film on the surface of a metal substrate,
  The film contains hard particles and a metal material, and has a Young's modulus of 250 Gpa or more.
  The hard particles are one or more selected from carbides, borides or oxides,
  A sliding member characterized in that the film contains a large number of hard particles having an equivalent circle diameter of 1.2 μm to 5 μm on the surface side of the metal base side. The Vickers hardness (Hv) of the said film is 1000-1400, The sliding member as described in any one of the Claims 1-3 characterized by the above-mentioned. The area ratio of the hard particles in the film cross section is 55.3% or more and 68.8% or less, and the equivalent circle diameter of the hard particles is 1.2 μm to 5 μm. 5.5% or more and 28.8% or less,
The cross-sectional porosity of the film is 1.06% by volume or less,
The sliding member according to any one of claims 1 to 4, wherein a Young's modulus of the film is not less than 261 Gpa and not more than 509 Gpa, and a Vickers hardness (Hv) is not less than 1019 and not more than 1327 .   The thickness of the said film is 5 micrometers or more and 600 micrometers or less, The sliding member as described in any one of the Claims 1-5 characterized by the above-mentioned. A power transmission device in which a plurality of sliding members contact each other to transmit power,
A power transmission apparatus characterized in that the sliding member is the sliding member according to any one of claims 1 to 6 . It is a manufacturing method of the sliding member according to any one of claims 1 to 6 , wherein the powder containing the hard particles and the metal material is heated and sprayed on the surface of the metal base material to form a film. The manufacturing method of the sliding member characterized by the above. The primary particle diameter of the hard particle in the said powder is 2 micrometers-5 micrometers, The manufacturing method of the sliding member of Claim 8 characterized by the above-mentioned.   The method of manufacturing a sliding member according to claim 8, wherein the formation of the film is performed in the atmosphere.

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