JP2021095933A - Slide member - Google Patents

Abstract

To provide a slide member having a compact construction to develop friction force even in an initial slide state, equivalent to that in a steady slide state.SOLUTION: The slide member includes a first metal member (1000) and a second metal member (2000), the first metal member including at least an embrittled layer (1010) formed on the top surface, and a hardened nitrided layer (1020) formed below the embrittled layer, the second metal member including at least a phosphate film layer (2010) formed on the top surface. The first metal member and the second metal member abut on each other at all times with one being pushed against the other, and relatively slide using an abrasion powder layer (1011) formed with the embrittled layer (1010) worn, as a boundary.SELECTED DRAWING: Figure 4

Description

The technology disclosed in this application relates to sliding members.

In a vehicle or the like, a damper device is provided on a torque transmission path between a drive source such as an engine and a transmission to absorb vibration (fluctuation) of torque transmitted from the drive source toward the transmission. The damper device is incorporated in, for example, a clutch device.

As a general configuration of a damper device, a coil spring is interposed between a disc plate as an input member that can rotate relative to each other and a hub as an output member, and torque fluctuates by utilizing elastic deformation of the coil spring. There is a known technique for absorbing and attenuating. Further, there is also known a technique of generating hysteresis torque based on friction to absorb and attenuate torque fluctuations. Furthermore, a damper device having a limiter mechanism that generates slip and forcibly shuts off torque transmission when a variable torque that cannot be absorbed even by using the elastic deformation of the coil spring or the hysteresis torque described above is generated has been proposed. There is.

The damper device adopts, for example, the configuration shown in FIG. 1, and mainly includes a cover plate 10, a support plate 20, a pressure plate 30, a disc plate 40, and a disc spring 50, and further includes a pressure plate 30 and a disc. A friction material 60 is provided between the plates 40 and between the disc plate 40 and the cover plate 10, respectively. In the damper device having such a configuration, torque is transmitted from the cover plate 10 (and the pressure plate 30) to the disc plate 40 via the friction material 60. On the other hand, when an excessive torque fluctuation occurs on the drive source side, the cover plate 10 and the pressure plate 30 slide with respect to the disc plate 40 via the friction material 60, so that the cover plate 10 (and the pressure plate 30) Torque transmission to the disc plate 40 is cut off. In this way, the cover plate 10, the pressure plate 30, and the disc plate 40 slide with each other via the friction material 60 (the cover plate 10 and the disc plate 40 slide with each other, and the pressure plate 30 and the disc plate 40 and the disc plate 40 slide with each other. It can be regarded as a sliding member in which the plate 40 slides on each other). Damper devices that employ sliding members with such a configuration are disclosed in, for example, Patent Document 1, Patent Document 2, and Patent Document 3.

Japanese Unexamined Patent Publication No. 2007-218346 Japanese Unexamined Patent Publication No. 2010-230162 Japanese Unexamined Patent Publication No. 2013-24364

However, if the configuration in which the friction material described above is provided between the sliding members is adopted, there are problems in that the sliding member becomes larger by the amount of the friction material and that the number of parts in the sliding member increases. is there.

On the other hand, when the pressure plate 30 and the disc plate 40, and the disc plate 40 and the cover plate 10 are directly slid between the metal members without providing the friction material between the sliding members, the initial sliding is performed as shown in FIG. The frictional force in the moving state becomes relatively lower than the frictional force in the steady sliding state (see the graph of the conventional material in FIG. 2). Therefore, in order to exert the function as the sliding member as described above in the damper device (in order to develop the frictional force required to exert the function as the sliding member), the sliding member is used at the time of shipment from the factory. It is necessary to perform preliminary sliding between the moving members, which is troublesome and costly. The initial sliding state means that the two members slide in a state where a predetermined amount of wear powder is not accumulated between the members that slide with each other. Further, the steady sliding state means that the two members slide in a state where a predetermined amount of wear powder is accumulated between the members that slide with each other. Therefore, the sliding of the two members transitions to the steady sliding state after passing through the initial sliding state, and the frictional force (friction coefficient) between the two members in the steady sliding state is the initial sliding state. It is high and stable compared to.

Therefore, various embodiments are provided to provide a sliding member that can be compactly configured and that exhibits a frictional force equivalent to that of a steady sliding state even in an initial sliding state.

The sliding member according to one aspect includes a first metal member and a second metal member, and the first metal member is formed of an embrittlement layer formed on the outermost surface thereof and under the embrittlement layer. The second metal member contains at least a phosphate film layer formed on the outermost surface thereof, and one of the first metal member and the second metal member presses against the other. They are always in contact with each other and slide relative to each other with the wear powder layer formed by the wear of the embrittlement layer as a boundary.

According to this configuration, since no friction material is used, it is more compact than the conventional one, and the frictional force (friction coefficient) between the first metal member and the second metal member is the initial friction. Even in the moving state, it can be equivalent to the steady sliding state. Further, according to this configuration, when the first metal member and the second metal member slide, the wear debris layer is efficiently formed, so that the efficiency is changed from the initial sliding state to the steady sliding state. It is possible to make a transition (early).

Further, in the sliding member according to one aspect, the embrittlement layer is preferably formed of an oxide, a nitride, or a composite thereof.

With this configuration, when the first metal member and the second metal member slide, the embrittlement layer can be easily worn to form the wear powder layer more efficiently. Will be.

Further, in the sliding member according to one aspect, the embrittlement layer has a microporous structure.

With this configuration, when the first metal member and the second metal member slide, the embrittlement layer is more easily worn to form the wear powder layer more efficiently. Is possible.

Further, in the sliding member according to one aspect, the microporous structure preferably has a porous size of 2 μm or less.

With this configuration, when the first metal member and the second metal member slide, the embrittlement layer is more easily worn to form the wear powder layer more efficiently. Is possible.

Further, in the sliding member according to one aspect, the thickness of the cured nitride layer is preferably larger than the thickness of the embrittlement layer.

This configuration leads to an improvement in the durability of the first metal member and the second metal member, and provides a stable frictional force (friction coefficient) between the first metal member and the second metal member. Can be secured.

According to various embodiments, it is possible to provide a sliding member that can be compactly configured and that exhibits a frictional force equivalent to that of a steady sliding state even in an initial sliding state.

It is the schematic sectional drawing which shows typically the structure of the conventional damper apparatus. It is a graph which shows the transition of the friction coefficient of the conventional material (conventional sliding member) and the sliding member which concerns on one Embodiment in an initial sliding state and a steady sliding state. It is schematic cross-sectional view which shows typically the structure of the damper device which incorporated the sliding member which concerns on one Embodiment. It is schematic cross-sectional view which shows typically the structure of the sliding member which concerns on one Embodiment. It is a micrograph which shows the cross section in the non-sliding state near the boundary between the 1st metal member and the 2nd metal member used for the sliding member which concerns on one Embodiment. It is a micrograph which shows the cross section in the initial sliding state near the boundary of the 1st metal member used for the sliding member which concerns on one Embodiment. It is a graph which shows the relationship between the depth from the outermost surface and the hardness (hardness) of the 1st metal member used for the sliding member which concerns on one Embodiment. It is a graph which shows the relationship between the Vickers hardness of the embrittlement layer and the wear amount of the 1st metal member. It is a graph which shows the relationship between the porous size of the embrittlement layer and the wear amount of the 1st metal member. It is a graph which shows the relationship between the sliding angle and the friction coefficient when the sliding member which uses the 1st metal member and the 2nd metal member which concerns on one Embodiment slides.

Hereinafter, various embodiments will be described with reference to the accompanying drawings. The same reference numerals are given to the common constituent requirements in the drawings. It should also be noted that the components represented in one drawing may be omitted in another for convenience of explanation. Furthermore, it should be noted that the attached drawings are not always drawn to the correct scale.

1. 1. Configuration of Damper Device Incorporating a Sliding Member The sliding member according to one embodiment can be applied to a device / component that requires a sliding operation with a constant frictional force, for example, an engine, a motor, or the like. It can be applied to a damper device that absorbs vibration (fluctuation) of torque transmitted from a drive source to a transmission. Therefore, an example of an outline of the overall configuration of the damper device in which the sliding member according to the embodiment is incorporated will be described with reference to FIG. Needless to say, the sliding member according to the embodiment can also be applied to a damper device having a general configuration as shown in FIG. FIG. 3 is a schematic cross-sectional view schematically showing the configuration of the damper device 1 in which the sliding member according to the embodiment is incorporated.

The damper device 1 incorporating the sliding member according to the embodiment is provided on a drive source (not shown) such as an engine or a motor and a power transmission path such as a transmission (not shown), and the drive source is provided. The power is transmitted via a flywheel (corresponding to reference numeral 70 in FIG. 1 and not shown for convenience in FIG. 3), and the power is transmitted (output) to a transmission or the like.

The damper device 1 absorbs and attenuates torque vibration. As shown in FIG. 3, the damper device 1 mainly has a lining plate 100, a disc plate 200, a hub 300, and a pressure plate 400 as a first rotating body in which power is transmitted from a flywheel via a mounting plate 5. Includes a disc spring 500 as an urging body, an elastic mechanism 600, and a hysteresis torque generating member 700. In the present specification, the axial direction means a direction extending parallel to the rotation axis O, the radial direction means a direction orthogonal to the rotation axis O, and the circumferential direction means the circumference of the rotation axis O. It shall mean the direction of orbit.

In the damper device 1, the lining plate 100 arranged on the most upstream side on the power transmission path is a rotation in which power derived from a drive source such as an engine or a motor is connected to the drive source, as shown in FIG. It is transmitted via a shaft (not shown), a flywheel, and a mounting plate 5. The lining plate 100 is fixed to the mounting plate 5 via bolts, nuts, or the like.

Further, the lining plate 100 is arranged so as to be sandwiched between the pressure plate 400 and the first plate 201 constituting the disc plate 200. With this configuration, when the pressure plate 400 is urged by the disc spring 500 as an urging body described later, the lining plate 100 is pressed so as to be pressed against the first plate 201. As a result, the power transmitted to the lining plate 100 is transmitted to the first plate 201 (disc plate 200).

By the way, the lining plate 100, the pressure plate 400, and the disc spring 500 cause slippage when the damper device 1 cannot completely absorb the torque fluctuation (the power transmission from the lining plate 100 to the first plate 201 is cut off). It can function as a limiter mechanism. That is, the lining plate 100 and the first plate 201 rotate relative to each other and slide. Therefore, the lining plate 100 and the first plate 201 are always in contact with each other and slide with each other as long as the lining plate 100 and the first plate 201 do not cause slippage. It can be regarded as such a sliding member. In this case, either one of the lining plate 100 and the first plate 201 can be regarded as the first metal member 1000, and the other can be regarded as the second metal member 2000.

In the damper device 1, the disc plate 200 is a member in which the power from the drive source is transmitted via the lining plate 100 described above. The disc plate 200 is formed of, for example, a metal material, and is rotatably provided around a rotation axis O with a hub 300, which will be described later, interposed therebetween, as shown in FIG. The disc plate 200 includes a first plate 201 and a second plate 202 as a pair of plate members that are provided on both sides of the hub 300 in the axial direction and rotate around the rotation axis O.

As described above, power is directly transmitted from the lining plate 100 to the first plate 201. The second plate 202 is arranged so as to face the first plate 201 in the axial direction, and rotates integrally with the first plate around the rotation axis O.

Here, the first plate 201 and the second plate 202 are integrated with the first plate 201 at the connecting portion 220 provided on the second plate 202. Further, the first plate 201 is provided with a first hole (not shown) for receiving the connecting portion (not shown), and the connecting portion is inserted into the first hole and crimped so that the first plate 201 And the second plate 202 are integrated.

Further, as shown in FIG. 3, the second plate 202 is provided with a support portion 225 for supporting the disc spring 500, which will be described later. The support portion 225 provided on the second plate 202 may have a shape that protrudes from the main portion 202x in a substantially L-shape in the axial direction opposite to the direction facing the first plate 201. However, the shape of the support portion 225 is not limited to a substantially L shape as long as it can support the disc spring 500, and may be changed as appropriate.

The connecting portion 220 and the supporting portion 225 provided on the second plate 202 are provided at positions radially outside the hub 300, which will be described later, and adjacent to each other in the circumferential direction of the second plate 202.

By the way, the first plate 201 and the second plate 202 have a shape slightly bulging in the axial direction so as to cooperate with each other to form a storage region 203 for accommodating the elastic mechanism body 600 described later. A conventionally known structure can be adopted for the accommodating area 203, for example, in order to accommodate the elastic body 610 extending along the circumferential direction of the disc plate 200, the accommodating region 203 is substantially linear along the circumferential direction of the disc plate 200. Or it extends on a substantially arc. The hub 300, which will be described later, is provided with a window hole 301 corresponding to the accommodation area 203 described above.

Next, the hub 300 in the damper device 1 functions as an output member of the damper device 1, and has, for example, a shape formed of a metal material and extending substantially in an annular shape as a whole, and is formed on the first plate 201 and the second plate 202. It is sandwiched and provided around the rotation shaft O so as to be rotatable relative to the disc plate 200 (first plate 201 and second plate 202). Further, as shown in FIG. 3, the hub 300 is spline-coupled to the input shaft by inserting the input shaft (not shown) of the transmission into the through hole 303 formed in the substantially cylindrical cylindrical portion 302. be able to. Further, the hub 300 has a disk portion 305 having an outer diameter from the cylindrical portion 302 toward the outer side in the radial direction.

As described above, the disk portion 305 is formed with a window hole 301 having a shape corresponding to the accommodating area provided in the disc plate 200. These window holes 301 provided in the hub 300 are provided corresponding to the configuration of the elastic mechanism body 600, which will be described later, and more specifically, the number of elastic bodies 610. That is, the elastic mechanism body 600, which will be described later, is housed in the window hole 301.

As the hub 300, in addition to the structure as described above, a hub 300 that is appropriately combined with other conventionally known structures can be adopted.

Next, the disc spring 500 as an urging body in the damper device 1 constitutes the above-mentioned limiter mechanism, and urges the above-mentioned lining plate 100 so as to be pressed against the first plate 201 via the pressure plate 400. This is a component that realizes power transmission from the lining plate 100 to the first plate 201 (disc plate 200).

As the disc spring 500, a conventionally known structure can be used. The disc spring 500 is supported by the above-mentioned support portion 225 provided on the disc plate 200 (second plate 202).

Next, as shown in FIG. 3, the elastic mechanism body 600 in the damper device 1 is mainly composed of an elastic body 610 in which a coil spring is mainly used and a pair of seat members 620 that support the elastic body in the circumferential direction. To.

Then, the elastic mechanism body 600 is housed in the housing area 203 provided in the disc plate 200 described above (and in the window hole 301 provided in the hub 300 described above). That is, the above-mentioned seat member 620 is supported by the accommodating region in the circumferential direction.

With the above configuration, the elastic body 610 can elastically connect the disc plate 200 and the hub 300 in the rotational direction via the seat member 620. That is, the power from a drive source such as an engine or a motor is transmitted in the order of the disc plate 200, one of the pair of seat members 620, the elastic body 610, the other of the pair of seat members 620, and the hub 300. .. Further, when the disc plate 200 and the hub 300 rotate relative to each other, the elastic body 610 is compressed and deformed, so that the torque fluctuation is absorbed.

Next, the hysteresis torque generating member 700 in the damper device 1 mainly rotates integrally with the substantially annular first hysteresis plate 701 and the second plate 202 in the disc plate 200, which rotate integrally with the first plate 201 in the disc plate 200. A second hysteresis plate 702 on a substantially annular ring, a substantially annular third hysteresis plate 703 that rotates integrally with the hub 300, a fourth hysteresis plate 704 sandwiched between the first hysteresis plate 701 and the third hysteresis plate 703, and a second A fifth hysteresis plate 705 sandwiched between the hysteresis plate 702 and the third hysteresis plate 703, a first countersunk spring 706 supported by the first plate 201 and arranged between the first plate 201 and the first hysteresis plate 701, and a hub. It is composed of a second countersunk spring 707 supported by 300 (disk portion 305) and arranged between the hub 300 (disk portion 305) and the third hysteresis plate 703. The first hysteresis plate 701, the second hysteresis plate 702, the third hysteresis plate 703, the fourth hysteresis plate 704, and the fifth hysteresis plate 705 are configured to be slightly movable in the axial direction.

First, the third hysteresis plate 703 is configured to be urged by the second disc spring 707 in a direction away from the hub 300 (disk portion 305) and pressed against the fourth hysteresis plate 704. As a result, a hysteresis torque is generated between the third hysteresis plate 703 and the fourth hysteresis plate 704.

Next, the first hysteresis plate 701 is configured to be urged by the first disc spring 706 in a direction away from the first plate 201 and pressed against the fourth hysteresis plate 704. As a result, a hysteresis torque is generated between the first hysteresis plate 701 and the fourth hysteresis plate 704.

Further, when the urging force of the first disc spring 706 urging the first hysteresis plate 701 is larger than the urging force of the second disc spring 707 urging the third hysteresis plate 703, the first disc spring 706 is attached. The urged first hysteresis plate 701 is axially oriented (in FIG. 3) so as to press the fourth hysteresis plate 704, the third hysteresis plate 703, the hub 300, and the fifth hysteresis plate 705 against the second hysteresis plate 702. Moves to the left of the page). As a result, between the fourth hysteresis plate 704 and the axially extending portion 705y of the fifth hysteresis plate 705, between the third hysteresis plate 703 and the radial extending portion 705x of the fifth hysteresis plate 705, and the fifth. Hysteresis torque can be generated between the radial extension portion 705x of the hysteresis plate 705 and the second hysteresis plate 702.

In the hysteresis torque generating member 700 described above, since the third hysteresis plate 703 and the fourth hysteresis plate 704 are members that are always in contact with each other and slide, they can be regarded as the sliding members according to the embodiment. it can. Similarly, the two members that generate the hysteresis torque as described above, such as the first hysteresis plate 701 and the fourth hysteresis plate 704, can also be regarded as the sliding members according to the embodiment.

The outline of the damper device 1 in which the sliding member according to the embodiment is incorporated is as described above, but in addition to the above-mentioned components, other conventionally known components may be appropriately combined.

2. Configuration of Sliding Member Next, an outline of the configuration of the sliding member according to the embodiment incorporated in the damper device 1 will be described with reference to FIGS. 2 and 4 to 9. FIG. 2 is a graph showing the transition of the friction coefficient of the conventional material (conventional sliding member) and the sliding member according to one embodiment in the initial sliding state and the steady sliding state. FIG. 4 is a schematic cross-sectional view schematically showing the configuration of the sliding member according to the embodiment. FIG. 5 is a photomicrograph showing a non-sliding cross section near the boundary between the first metal member 1000 and the second metal member 2000 used for the sliding member according to the embodiment. FIG. 6 is a photomicrograph showing a cross section of the first metal member 1000 used for the sliding member according to the embodiment in the initial sliding state near the boundary. FIG. 7 is a graph showing the relationship between the depth from the outermost surface and the hardness (hardness) of the first metal member 1000 used for the sliding member according to the embodiment. FIG. 8 is a graph showing the relationship between the Vickers hardness of the embrittlement layer 1010 and the amount of wear of the first metal member. FIG. 9 is a graph showing the relationship between the porous size of the embrittlement layer 1010 and the amount of wear of the first metal member 1000. FIG. 10 is a graph showing the relationship between the sliding angle and the friction coefficient when the sliding member in which the first metal member 1000 and the second metal member 2000 according to the embodiment are used slides. In FIGS. 5 and 6, for convenience, a gap painted in black between the first metal member 1000 and the second metal member 2000 is shown on the photograph, but this gap is used only for analysis. It should be noted that the resin that was used is only expressed, and the gap is omitted in the actual sliding member.

It should be noted that the sliding member according to one embodiment is basically composed of two members that are always in contact with each other, and for example, the lining plate 100 and the first plate 201 described above are described above. Can be taken as an example of a sliding member. The sliding member according to one embodiment is composed of a first metal member 1000 (for example, a lining plate 100) and a second metal member 2000 (for example, a first plate 201).

As the material (base material) of the first metal member 1000 and the second metal member 2000, any steel material such as a commercially available iron material or rolled steel that can secure a predetermined rigidity generally required for the damper device 1 is used without particular limitation. However, from the viewpoint of soft nitriding treatment described later, it is composed of C (carbon), Mn (manganese), Al (aluminum), Cr (chromium), Si (silica), Ti (titanium), and / or V (vanadium). It is preferably a steel material contained as a part of the components.

2-1. First metal member 1000
As shown in FIG. 4, the first metal member 1000 includes at least an embrittlement layer 1010 formed on the outermost surface thereof and a hardened nitrided layer 1020 formed under the embrittlement layer 1010. On the other hand, the second metal member 2000 includes at least a phosphate film layer 2010 formed in an uneven shape on the outermost surface thereof. When used, the first metal member 1000 and the second metal member 2000 are used as sliding members in which one is pressed against the other and always abuts against each other.

As shown in FIG. 5, the embrittlement layer 1010 has a microporous structure in which innumerable fine porouss are formed in the steel material, and the surface thereof is before the initial sliding state (when not sliding). Exhibits an uneven shape. Therefore, when it slides with the phosphate film layer 2010 formed on the outermost surface of the second metal member 2000, it easily wears to form a wear debris layer. That is, as shown in FIG. 6, soon after the initial sliding state starts, the uneven surface of the embrittlement layer 1010 is scraped (digged up) by the phosphate film layer 2010 of the second metal member 2000. .. As a result, an extremely flat wear powder layer 1011 is formed on the outermost surface of the embrittlement layer 1010. The wear powder layer 1011 formed in this way is formed with the first metal member 1000 and the second metal member 2000. It becomes the sliding surface (boundary) of.

Next, a method of forming the embrittled layer 1010 and the hardened nitrided layer 1020 formed on the first metal member 1000 will be described. The embrittlement layer 1010 and the hardened nitrided layer 1020 are formed by soft nitriding treatment from the outermost surface of the first metal member 1000 to a predetermined depth (thickness).

Either the gas method or the salt bath method can be used for the soft nitriding treatment. For example, by optimizing an atmospheric gas such as ammonia, a nitride layer having a microporous structure is formed on the surface layer of the first metal member 1000. can do. Further, by exposing the polar surface layer of the microporous structure formed on the surface layer of the first metal member 1000 to water vapor, the polar surface layer can be replaced with iron oxide having high corrosion resistance. By applying such a series of soft nitriding treatments to the first metal member 1000, the embrittlement layer 1010 can be formed at a thickness within 10 μm from the outermost surface of the first metal member 1000. The embrittlement layer 1010 is formed of an oxide, a nitride, or a composite thereof based on the series of soft nitriding treatments described above.

By the way, the thickness of the embrittled layer 1010 (depth from the outermost surface of the first metal member 1000) formed as described above is configured to be within 10 μm as shown in FIG. 7, for example (region A in FIG. 7). .. Further, as shown in FIG. 7, the hardness of the embrittlement layer 1010 is such that the Vickers hardness is 350 HV or less, so that the embrittlement layer 1010 is easily dug up in the phosphate film layer 2010 in the second metal member 2000. As the hardness of the embrittlement layer 1010, as shown in FIG. 8, it can be seen that the amount of wear of the first metal member 1000 is reduced by setting the Vickers hardness to 350 HV. That is, the amount of wear of the first metal member 1000 can be reduced by shifting the sliding member from the initial sliding state to the steady sliding state at an early stage.

On the other hand, as shown in FIG. 7, the thickness of the cured nitride layer 1020 formed as described above is larger than the thickness of the embrittlement layer 1010, and is formed to be, for example, 60 μm or more (region B in FIG. 7). By making the thickness of the hardened nitrided layer 1020 larger than the thickness of the embrittlement layer 1010 in this way, the durability of the first metal member 1000 and the second metal member 2000 is improved, and the first metal member 1000 and the second metal member 1000 and the second metal member 1000 are improved. A stable frictional force (friction coefficient) can be secured between the metal member 2000 and the metal member 2000.

The conventional material (sliding member in which the metal members slide directly with each other) shown in FIG. 7 is not subjected to the above-mentioned soft nitriding treatment, and only the surface of the first metal member 1000 is subjected to a hardening treatment. A hardened layer (hardened nitrided layer) (see region D in FIG. 7) is formed on the outermost surface of the first metal member 1000 in the conventional material. Since the hardness of the hardened layer of the conventional material formed as described above is about 400 HV to 700 HV Vickers hardness, it is not easily worn like the embrittled layer 1010. Therefore, as compared with the sliding member according to one embodiment, it takes time for the wear powder layer to be formed. That is, it takes a considerable amount of time to reach the steady sliding state.

By the way, as shown in FIGS. 4 to 6, when the first metal member 1000 is subjected to soft nitriding treatment, a diffusion layer 1030 whose base metal structure is reinforced with nitrogen is formed under the hardened nitriding layer 1020 ( In FIG. 7, see region C for the sliding member according to one embodiment). Further, under the diffusion layer 1030, a base material layer 1050 is formed in which the base material structure is formed as it is without being affected by nitrogen. As shown in FIG. 7, it is preferable that the hardness of the diffusion layer 1030 has a Vickers hardness of 300 HV or more from the viewpoint of reducing the amount of wear of the first metal member 1000.

Next, as shown in FIG. 9, the porous size of the embrittled layer 1010 produced as described above in the microporous structure is preferably 2 μm or less, and particularly preferably 1 μm or less. When the porous size is 2 μm or less, the amount of wear of the first metal member 1000 can be reduced to 2/3 or less as compared with the case where the porous size is about 10 μm. The fact that the amount of wear of the first metal member 1000 is small means that it is possible to shift from the initial sliding state to the steady sliding state at an early stage.

The coefficient of friction of the sliding member is generally required to be 0.6 or more. Considering this, the embrittled layer 1010 is preferably roughened, and the surface roughness thereof is preferably R _zjis (10-point average roughness) of 15 μm or less, as shown in FIG. It is particularly preferably 8 μm or more and 11 μm or less.

2-2. Second metal member 2000
As shown in FIG. 4, the phosphate film layer 2010 is formed on the outermost surface of the second metal member 2000 (the surface of the base material 2020 of the second metal member 2000) as described above. As the phosphate, for example, zinc phosphate can be used. The phosphate film layer 2010 is formed by applying a general bonde treatment to the outermost surface of the second metal member 2000.

As shown in FIG. 2, the sliding member according to the embodiment composed of the first metal member 1000 and the second metal member 2000 including the above configuration has an initial sliding state (test number of 10,000 or less). ), The friction coefficient is 0.65 or more, and the initial sliding state (region P in FIG. 2) can be shifted to the steady sliding state (region Q in FIG. 2) when the number of tests is about 25,000. On the other hand, the conventional material has a friction coefficient of 0.6 or less at the initial stage of the initial sliding state, and shifts from the initial sliding state (region X in FIG. 2) to the steady sliding state (region Y in FIG. 2). It takes about 150,000 tests. Therefore, the sliding member according to one embodiment can shift from the initial sliding state to the steady sliding state at an early stage as compared with the conventional material.

As described above, various embodiments have been exemplified, but the above embodiments are merely examples and are not intended to limit the scope of the invention. The above-described embodiment can be implemented in various other forms, and various omissions, substitutions, and changes can be made without departing from the gist of the invention.

1 Damper device 1000 1st metal member 1010 Embrittlement layer 1011 Abrasion powder layer 1020 Hardened nitrided layer 2000 2nd metal member 2010 Phosphate film layer

Claims (5)

Equipped with a first metal member and a second metal member,
The first metal member includes at least an embrittlement layer formed on the outermost surface thereof and a hardened nitrided layer formed under the embrittlement layer.
The second metal member contains at least a phosphate film layer formed on the outermost surface thereof.
One of the first metal member and the second metal member is pressed against the other and always abuts against each other, and slides relative to each other with a wear debris layer formed by the wear of the embrittlement layer as a boundary. To do,
Sliding member. The sliding member according to claim 1, wherein the embrittled layer is formed of an oxide, a nitride, or a composite thereof. The sliding member according to claim 1 or 2, wherein the embrittled layer has a microporous structure. The sliding member according to claim 3, wherein the microporous structure has a porous size of 2 μm or less. The sliding member according to any one of claims 1 to 3, wherein the thickness of the cured nitride layer is larger than the thickness of the embrittlement layer.

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