Sliding member
Patent Information
- Application Number
- JP2023069931
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-04-21
- Publication Date
- 2025-11-17
AI Technical Summary
Existing sliding members in internal combustion engines face issues with peeling between the bearing alloy and intermediate layers, particularly when using Zn treatment, which fails to provide sufficient adhesive strength under high loads.
A sliding member design with a Zn-containing adhesive layer extending over a wide area, including the axial end face, and intermediate layers composed of Ag, Ni, or Co, with a coating layer of Bi, Pb, or Sn, ensuring continuous coverage and improved adhesion.
The design enhances adhesive strength and prevents peeling, particularly when the adhesive layer covers 70% or more of the axial end face, resulting in improved fatigue resistance and reduced peeling points.
Smart Images
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Abstract
Description
[Technical field]
[0001] The present invention relates to a sliding member for an internal combustion engine, and more particularly to a sliding member in which a coating layer is laminated on a substrate via an intermediate layer. [Background technology]
[0002] As sliding members in internal combustion engines, sliding bearings such as half bearings and half thrust bearings used in, for example, crankshafts and connecting rods of internal combustion engines for automobiles are known. Conventionally, half bearings use a semi-annular metal member in which a bearing alloy (base material) made of an Al alloy is lined on the surface of a steel backing metal, and then the bearing alloy is positioned on the inner peripheral side, and a coating layer is coated on the bearing alloy by electroplating or the like via an intermediate layer. The coating layer is used to improve compatibility with the mating material, and the intermediate layer is used to improve adhesion between the bearing alloy and the coating layer.
[0003] However, in a sliding member, when a coating layer is coated on an Al alloy bearing alloy via an intermediate layer mainly composed of Ag, there is a problem that peeling occurs between the bearing alloy and the intermediate layer. In order to address this problem, Patent Document 1 provides a first intermediate layer mainly composed of Cu on the bearing alloy (lining), and further provides a second intermediate layer mainly composed of Ag on this first intermediate layer 1, thereby reducing the possibility of peeling between the lining and the second intermediate layer and reducing the possibility of Cu diffusing from the first intermediate layer to the coating layer, thereby reducing the fatigue resistance.
[0004] Patent Document 2 also proposes that in order to improve the adhesion of a coating layer to a bearing alloy made of a Cu alloy or an Al alloy in a sliding member, the crystal grains of the intermediate layer are controlled to grow larger from the bearing alloy side toward the coating layer side, and that the intermediate layer is formed from a single metal such as Ag, Cu, or Co. Patent Document 2 also proposes that in order to improve fatigue resistance, the growth of the crystal grains in the coating layer is controlled so that the crystal grains become columnar crystals that are long in the thickness direction of the coating layer.
[0005] In recent years, sliding components using Al alloys as bearing alloys have been widely adopted, but as the power output of recent internal combustion engines for automobiles continues to increase, higher fatigue resistance is required for sliding components, and the adhesiveness of currently proposed intermediate layers is insufficient. On the other hand, it has become mainstream to improve adhesive strength by treating Al materials with Zn, and Zn treatment is also used in the surface treatment of Al materials used to reduce the weight of automobiles and in semiconductor processing. However, because sliding components are subjected to high loads, Zn treatment does not provide sufficient adhesive strength for the required performance. [Prior art documents] [Patent documents]
[0006] [Patent Document 1] JP 2020-132924 A [Patent Document 2] JP 2006-266445 A Summary of the Invention [Problem to be solved by the invention]
[0007] Therefore, an object of the present invention is to improve the adhesion of an intermediate layer and a coating layer to a metal member in a sliding member in which an adhesive layer containing Zn as a main component is provided on a metal member having a lining layer made of an Al alloy. [Means for solving the problem]
[0008] 1 shows a part of a cross section of a conventional sliding member 101 having a circular ring shape, taken along a plane including an axis. As can be seen, the sliding member 101 has a metal member 110 including a steel backing layer 111 and an Al alloy lining layer 112, an adhesive layer 120 mainly composed of Zn coated on the surface of the lining layer 112, an intermediate layer 130 laminated on the adhesive layer, and a coating layer 140 laminated on the intermediate layer. The inventors have found that in the conventional sliding member 101, when a high load is applied to the sliding surface 140a, peeling occurs at a point A on the axial end face where the adhesive layer 120 is disconnected from the meta member 110, and sufficient adhesive strength is not obtained.
[0009] Therefore, in order to achieve the above object, according to a first aspect of the present invention, A metal member having a semicircular ring shape, the metal member having a back metal layer disposed on an outer peripheral surface side and a lining layer made of an Al alloy disposed on an inner peripheral surface side; an adhesive layer containing Zn as a main component laminated on an inner peripheral surface of the metal member; an intermediate layer containing Ag, Ni or Co as a main component laminated on the adhesive layer; A coating layer containing Bi, Pb or Sn as a main component laminated on the intermediate layer. A sliding member having The adhesive layer on the inner peripheral surface of the metal member extends continuously to further cover the axial end face of the metal member, and the ratio of the surface area of the adhesive layer covering the axial end face to the surface area of the axial end face is 30% or more, thereby providing a sliding member. This sliding member can be used, for example, as a half bearing. It is preferable to use an Fe-based metal or alloy for the back metal, but it is not limited to Fe-based metals, and Cu-based, Al-based, Ti-based, or other metals or alloys may be used depending on the intended use. When an Fe-based metal or alloy is used for the back metal, it is preferable to set the current density during plating to be higher on the back side. A Cu plating layer or the like may be provided between the back metal layer and the lining layer of the metal member. The adhesive layer is preferably formed on the inner peripheral surface of the metal member at least below the intermediate layer, but does not necessarily have to cover the entire inner peripheral surface of the metal member. For example, holes, grooves, etc. may be provided on the inner peripheral surface of the metal member. Furthermore, the adhesive layer needs only to extend so as to cover at least one axial end face of the metal member, but may also extend so as to cover both axial end faces.
[0010] In one embodiment of the present invention, the ratio of the surface area of the adhesive layer covering the axial end face to the surface area of the axial end face of the metal member can be 70% or more.
[0011] In another embodiment of the present invention, the adhesive layer covering the axial end surface extends continuously to further cover the outer peripheral surface of the metal member, and in this case the ratio of the surface area of the adhesive layer covering the outer peripheral surface to the surface area of the outer peripheral surface of the metal member can be 30% or more.
[0012] In yet another embodiment of the present invention, the intermediate layer and the covering layer are also laminated on an adhesive layer covering the axial end surface of the metal member, and the ratio of the surface area of the intermediate layer and the covering layer laminated on the adhesive layer covering the axial end surface to the surface area of the axial end surface of the metal member can be 30% or more.
[0013] In yet another embodiment of the present invention, the ratio of the surface area of the intermediate layer and coating layer laminated on the adhesive layer covering the axial end face to the surface area of the axial end face of the metal member can be 70% or more.
[0014] In yet another embodiment of the present invention, the intermediate layer and the covering layer are also laminated on an adhesive layer covering the outer peripheral surface of the metal component, and the ratio of the surface area of the intermediate layer and the covering layer laminated on the adhesive layer covering the outer peripheral surface to the surface area of the outer peripheral surface of the metal component can be 30% or more.
[0015] In yet another embodiment of the present invention, the sum of the thicknesses of the intermediate layer and the coating layer laminated on the adhesive layer covering the axial end face of the metal member can be less than the sum of the thicknesses of the intermediate layer and the coating layer laminated on the adhesive layer covering the inner surface of the metal member.
[0016] According to a second aspect of the present invention, A metal member having a semicircular ring shape, the metal member having a back metal layer disposed on a first axial end face side and an Al alloy lining layer disposed on a second axial end face side; an adhesive layer containing Zn as a main component and laminated on a second axial end surface of the metal member; an intermediate layer containing Ag, Ni or Co as a main component laminated on the adhesive layer; A coating layer containing Bi, Pb or Sn as a main component laminated on the intermediate layer. A sliding member having The adhesive layer on the second axial end face of the metal member extends continuously to further cover the inner and outer circumferential surfaces of the metal member, and the ratio of the surface area of the adhesive layer covering the inner or outer circumferential surface to the surface area of the inner or outer circumferential surface is 30% or more, thereby providing a sliding member. This sliding member can be used, for example, as a half thrust bearing. Effect of the Invention
[0017] According to the present invention, by performing Zn treatment not only on the inner peripheral surface of the metal member but also on the axial end surface, an adhesive layer is formed over a wide area of the metal member, that is, extending to an area not receiving high load. As a result, there is no end (point of discontinuity) of the adhesive layer under the intermediate layer receiving the load, and therefore no weak adhesive spots that can be the starting point of peeling are formed. In particular, when the surface area of the adhesive layer formed on the axial end surface is 70% or more of the surface area of the axial end surface of the metal member, more sufficient adhesive performance can be obtained.
[0018] Furthermore, if an adhesive layer is not present on the axial end face of the metal component, the coating layer and intermediate layer will not adhere easily. Therefore, when the axial end face is coated with a coating layer and an intermediate layer, it can be determined that an adhesive layer is also present underneath.
[0019] Also, as a starting point for peeling other than the area under the sliding surface receiving the load, peeling may occur around the boundary between the lining layer and the back metal layer, where the metal type changes, on the axial end face of the metal component.Since the thickness (radial length) of the lining layer is approximately 20% of the thickness (radial length) of the axial end face, if the surface area of the intermediate layer and coating layer formed on the axial end face is 30% or more of the surface area of the axial end face, it can be considered that the adhesive layer extends to the axial end face of the back metal layer.
[0020] The thickness (axial length) of the coating layer and intermediate layer deposited on the axial end face does not directly affect the bearing characteristics, but it is desirable that the thickness (axial length) of the coating layer and intermediate layer on the inner surface be thinner than the thickness (radial length) of the coating layer and intermediate layer to enable more appropriate assembly into the bearing housing.
[0021] Other objects, features and advantages of the present invention will become apparent from the following detailed description of the preferred embodiments of the present invention taken in conjunction with the accompanying drawings. [Brief description of the drawings]
[0022] [Figure 1] FIG. 1 is a diagram showing a part of a cross section of a conventional annular sliding member 101 taken along a plane including an axis line. [Diagram 2] FIG. 1 is a perspective view of a slide member 1 according to an embodiment of the present invention. [Diagram 3] FIG. [Figure 4] FIG. 4 is an exaggerated schematic diagram of a cross-sectional view taken along line BB in FIG. 3. [Diagram 5] FIG. [Figure 6] FIG. 2 is a diagram showing a metal member 10 in a state where only an adhesive layer 20 is laminated. [Figure 7]FIG. 1 is a diagram showing an outline of Zn treatment. [Figure 8] FIG. 2 is a diagram showing an assembled state of the metal member 10 during Zn treatment. [Figure 9] FIG. 2 is a schematic diagram of a fatigue test device for a bearing. [Figure 10] FIG. 4 is a diagram showing a load pattern on a bearing in a fatigue test. [Figure 11] FIG. 11 is a diagram showing a procedure for calculating a fatigue area ratio in a test bearing 501. [Figure 12] FIG. 2 is a schematic diagram showing a part of a cross section of a sliding member 1 according to another embodiment of the present invention, taken along a plane including an axis line. [Figure 13] FIG. 11 is a schematic diagram showing a part of a cross section of a sliding member 1 according to still another embodiment of the present invention, taken along a plane including an axis line. [Figure 14] FIG. 11 is a schematic diagram showing a part of a cross section of a sliding member 1 according to still another embodiment of the present invention, taken along a plane including an axis line. [Figure 15] FIG. 13 is a diagram showing a metal member 10 in a state where only an adhesive layer 20 is laminated, of a slide member 1 according to still another embodiment of the present invention. [Figure 16] FIG. 8 is a diagram showing a half thrust bearing 810 according to an embodiment of another aspect of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
[0024] (Structure of sliding members) Fig. 2 is a perspective view of the slide member 1 according to this embodiment, and Fig. 3 is a plan view of the slide member 1. As can be seen, the slide member 1 has a semicircular ring shape and defines a slide surface 2 on the inner circumferential side and a back surface 3 on the outer circumferential side.
[0025] Fig. 4 is a schematic diagram showing an exaggerated cross-sectional view taken along line BB in Fig. 3, and Fig. 5 is a perspective view of a metal member 10. The slide member 1 has a metal member 10 formed in a semicircular ring shape. The metal member 10 defines an inner circumferential surface 15, an outer circumferential surface 16, and an axial end surface 17. The metal member 10 has a layered structure including a backing layer 11 made of an Fe alloy on the outer circumferential side and a lining layer 12 made of an Al alloy on the inner circumferential side.
[0026] As shown in FIG. 4, an adhesive layer 20 mainly composed of Zn is laminated so as to cover the inner peripheral surface 15 of the metal member 10. The adhesive layer 20 further extends continuously from the inner peripheral surface 15 side of the metal member 10 to the axial end face 17 side (i.e., so as to cover the inner diameter side region of the axial end face 17), thereby covering at least 30% of the surface area of the axial end face 17. For ease of understanding, FIG. 6 shows the metal member 10 in a state where only the adhesive layer 20 is plated. In particular, FIG. 6(b) is a diagram of the axial end face 17 of the metal member 10 cut away, and FIG. 6(a) is a diagram of a portion 20a of the adhesive layer 20 formed on the axial end face 17. Therefore, in this embodiment, the ratio of the area of the adhesive layer 20a shown in FIG. 6(a) to the area of the axial end face 17 shown in FIG. 6(b) is 30% or more.
[0027] In this embodiment, the adhesive layer 20 extends a constant radial length L from the inner diameter side end portion 13 around the circumferential direction of the axial end face 17 and covers the inner diameter side region of the axial end face 17. However, according to the present invention, the length L of the adhesive layer 20 does not necessarily have to be constant around the circumferential direction as long as it covers at least 30% of the surface area of the axial end face 17.
[0028] 4, an intermediate layer 30 containing Ag, Ni or Co as a main component is formed on the adhesive layer 20. Therefore, in this embodiment, the intermediate layer 30 also extends a certain radial length L from the inner diameter side end 13 on the axial end face 17 of the metal member 10.
[0029] Similarly, a coating layer 40 containing Bi, Pb or Sn as a main component is formed on the intermediate layer 30. Therefore, in this embodiment, the coating layer 40 also extends a certain radial length L from the inner diameter side end 13 on the axial end face 17 of the metal member 10.
[0030] In this embodiment, the intermediate layer 30 and the coating layer 40 extend a certain radial length L from the inner diameter side end portion 13 on the axial end face 17 of the metal member 10, but this does not necessarily have to be the same as the radial length L of the adhesive layer 20, and may be longer or shorter than the radial length L of the adhesive layer 20.
[0031] (Method of manufacturing slide member) First, a bimetal is manufactured by lining a bearing alloy (lining layer 12) on the steel plate that constitutes the back metal layer 11. Next, the bimetal is processed into a semicircular ring shape to obtain the metal member 10.
[0032] After that, an overlay is applied to the lining layer 12 of the metal member 10 in the following manner. Note that the following plating conditions are an example in which the coating layer has a thickness of 2 to 10 μm, the intermediate layer has a thickness of 2 to 10 μm, and the adhesive layer has a thickness of 0.7 μm or less. (1) Adhesive layer (Zn) The Zn solution contains 40-80g / L zinc oxide, 400-500g / L caustic soda, 25-30g / L Rochelle salt, and 2-9g / L ferric chloride. The current density is 0.1-2A / dm on the inner side. 2 , rear side is 0.1~2A / dm 2 In other words, the current density is set higher on the rear side (Figure 7). (2) Intermediate layer (Ag) Use 30-60g / L silver cyanide, 100-200g / L sodium cyanide, and 10-30g / L sodium carbonate. The current density is 1.5-3A / dm 2 Set to. (3) Covering layer (Bi) Use 10-70g / L bismuth oxide, 30-150mL / L methanesulfonic acid, and 20-60mL / L HS-220S. Current density is 1-6A / dm 2 Set to.
[0033] The plating process is performed by assembling the metal members 10 in such a manner that spacers 80 are disposed so that gaps 81 are formed between the metal members 10 as shown in Fig. 8. By performing the plating process with the gaps 81 remaining, a coating can also be formed on the axial end faces 17 of the metal members 10. As an example, the relationship between the contact rate between the metal member and the spacer and the proportion of the surface area of the adhesive layer covering the axial end face can be set by the following formula. y=-x+100(±10%) Where: y (%) is the ratio of the surface area of the adhesive layer covering the axial end face to the surface area of the axial end face, x (%) is the contact rate between the metal member and the spacer. However, there is a possibility that the parts in contact with the spacer may be coated due to misalignment or deterioration of the spacer. In that case, you can prevent this by covering them with tape. In order to obtain the desired surface area of the adhesive layer and intermediate layer covering the axial end face, the contact rate between the metal member and the spacer can be set in the same manner as in the above formula, where y (%) is the ratio of the surface area of the adhesive layer and intermediate layer covering the axial end face to the surface area of the axial end face, and x (%) is the contact rate between the metal member and the spacer. However, the above ratio is merely an example, and the manufacturing method and formula for obtaining the surface area ratio of the adhesive layer and / or intermediate layer to the coating layer of the present invention are not limited to the above.
[0034] (Confirmation test) In order to evaluate the bearing performance, a fatigue test was carried out on the sliding members according to Examples 1 to 10 of the present invention. The test conditions and results are described below.
[0035] The fatigue test was carried out using a test apparatus 500 shown in Fig. 9. In the test apparatus 500, a test bearing 501 was attached to a support shaft 520 supported by a plurality of support bearings 510, and while the support shaft 520 was rotating, a load was applied to the test bearing 501 hydraulically using a load device 530, thereby inducing fatigue in the Bi, Pb coating on the sliding surface. The fatigue test conditions are as shown in Table 1. [Table 1]
[0036] Regarding the contact pressures shown in Table 1, a load was applied to the test bearing 501 according to the load pattern shown in Fig. 10. Specifically, the load was adjusted stepwise using the pressure adjustment valve 531 of the load device 530 up to the specified contact pressure of 120 MPa.
[0037] Fatigue resistance was evaluated by visually checking the appearance for the presence or absence of peeling or fatigue after the test. Specifically, the fatigue area was measured by approximating the fatigued part occurring on the sliding surface 2 of the test bearing 501 with an ellipse C, as shown in Fig. 11. Then, the fatigue area rate was calculated by calculating the ratio between the projected area of the sliding surface 2 and the area of the approximated ellipse C, and the evaluation was performed.
[0038] Table 2 shows the compositions and dimensional conditions of the sliding members according to Examples 1 to 10 and Comparative Examples 1 to 4, as well as the test results (ratio of projected area to fatigue area). In the table, "adhesive layer / axial end face area ratio (%)" indicates the area ratio of the adhesive layer formed on the axial end face to the total surface area of the axial end face of the metal member, "adhesive layer / outer peripheral surface area ratio (%)" indicates the area ratio of the adhesive layer formed on the outer peripheral surface to the total surface area of the outer peripheral surface of the metal member, "coating layer + intermediate layer / axial end face area ratio (%)" indicates the area ratio of the overlapping portion of the coating layer and intermediate layer formed on the axial end face to the total surface area of the axial end face of the metal member, "outer peripheral surface coating layer + outer peripheral surface intermediate layer axial end face area ratio (%)" indicates the area ratio of the overlapping portion of the coating layer and intermediate layer formed on the outer peripheral surface of the metal member to the total surface area of the outer peripheral surface of the metal member, and "fatigue area / projected area ratio" indicates the ratio of the projected area of the sliding surface 2 to the area of the approximated ellipse C, as determined by the above-mentioned appearance check.
[0039] From the test results, it can be seen that when the coverage rate of the adhesive layer on the axial end face exceeds 30%, the fatigue area rate is reduced compared to the comparative example, and the fatigue area rate is further reduced when the adhesive layer extends to the outer circumferential surface. Furthermore, the more intermediate layers and coating layers are formed on the adhesive layer, the more the fatigue area rate is reduced. [Table 2]
[0040] According to the present invention, the sliding member may have various embodiments. For example, as shown in Fig. 12, in the sliding member 1, the adhesive layer 20 may be formed over the inner peripheral surface, axial end face, and outer peripheral surface of the metal member 10, and in this case, the intermediate layer 30 and the coating layer 40 may be laminated only on the inner peripheral surface of the metal member 10. Alternatively, as shown in Fig. 13, the adhesive layer 20 may be formed over the inner peripheral surface, axial end face, and outer peripheral surface of the metal member 10, and the intermediate layer 30 and the coating layer 40 may be laminated on the adhesive layer 20.
[0041] According to the present invention, the adhesive layer 20 may occupy 30% or more of the area of the axial end face 17 of the metal member 10, and may not cover the entire axial end face 17. As shown in Figures 14 and 15, in the circumferential end face 17 of the metal member 17, the adhesive layer 20 may have a portion 20a extending continuously from the inner circumferential surface 15 side of the metal member 10 to the axial end face 17 side, and a portion 20b formed on the outer circumferential surface 16 side of the metal member 10. In this case, it is preferable that the sum of the surface areas of the portions 20a and 20b shown in Figure 15(a) is 70% or more of the surface area of the axial end face 17 shown in Figure 15(b).
[0042] In another aspect of the present invention, the sliding member of the present invention may be formed as a half thrust bearing (thrust washer) 801 as shown in Fig. 16. In this case, a sliding surface 802 of the half thrust bearing 801 corresponds to the inner circumferential surface 2 of the half bearing 1, a surface 803 opposite to the sliding surface 802 of the half thrust bearing 801 corresponds to the outer circumferential surface 3 of the half bearing 1, and an inner circumferential surface 804 and an outer circumferential surface 805 of the half thrust bearing 801 correspond to the axial end faces of the half bearing 1.
[0043] The above describes in detail the embodiments and examples of the present invention with reference to the drawings and in relation to the performance evaluation tests. However, the specific configurations are not limited to these, and modifications that do not depart from the gist of the present invention described in the claims are included in the present invention. [Explanation of symbols]
[0044] 1 Sliding member 2. Sliding surface 3 Back 10 Metal parts 11 Backing layer 12 Lining layer 13 Inner diameter end 15 Inner surface 16 Outer surface 17 Axial end face 20 Adhesive layer 20a Adhesive layer part 20b Adhesive layer part 30 Middle Class 40 Covering layer 80 Spacer 81 Gap 500 Test Equipment 501 Test bearing 510 Support bearing 520 Support shaft 530 Load device 531 Pressure Regulating Valve
Claims
1. A metal member having a semicircular ring shape, the metal member having a back metal layer disposed on an outer peripheral surface side and an Al alloy lining layer disposed on an inner peripheral surface side; an adhesive layer containing Zn as a main component and laminated on an inner circumferential surface of the metal member; an intermediate layer containing Ag, Ni or Co as a main component and laminated on the adhesive layer; A coating layer containing Bi, Pb or Sn as a main component laminated on the intermediate layer; A sliding member having a sliding member, wherein the adhesive layer on the inner peripheral surface of the metal member extends continuously so as to further cover an axial end face of the metal member, and a ratio of a surface area of the adhesive layer covering the axial end face to a surface area of the axial end face is 30% or more.
2. 2. The sliding member according to claim 1, wherein a ratio of a surface area of the adhesive layer covering the axial end face to a surface area of the axial end face of the metal member is 70% or more.
3. 2. The slide member according to claim 1, wherein the adhesive layer covering the axial end face extends continuously to further cover the outer circumferential surface of the metal member, and a ratio of a surface area of the adhesive layer covering the outer circumferential surface to a surface area of the outer circumferential surface of the metal member is 30% or more.
4. 2. The slide member according to claim 1, wherein the intermediate layer and the covering layer are also laminated on the adhesive layer covering the axial end face of the metal member, and a ratio of a surface area of the intermediate layer and the covering layer laminated on the adhesive layer covering the axial end face to a surface area of the axial end face of the metal member is 30% or more.
5. 5. The slide member according to claim 4, wherein a ratio of a surface area of the intermediate layer and the coating layer laminated on the adhesive layer covering the axial end face to a surface area of the axial end face of the metal member is 70% or more.
6. 5. The slide member according to claim 4, wherein the intermediate layer and the covering layer are also laminated on the adhesive layer covering the outer circumferential surface of the metal member, and a ratio of a surface area of the intermediate layer and the covering layer laminated on the adhesive layer covering the outer circumferential surface to a surface area of the outer circumferential surface of the metal member is 30% or more.
7. 2. The slide member according to claim 1, wherein a total thickness of the intermediate layer and the covering layer laminated on the adhesive layer covering the axial end face of the metal member is equal to or less than a total thickness of the intermediate layer and the covering layer laminated on the adhesive layer covering the inner circumferential surface of the metal member.
8. A metal member having a semicircular ring shape, the metal member having a back metal layer disposed on a first axial end face side and a lining layer made of an Al alloy disposed on a second axial end face side; an adhesive layer containing Zn as a main component and laminated on the second axial end surface of the metal member; an intermediate layer containing Ag, Ni or Co as a main component and laminated on the adhesive layer; A coating layer containing Bi, Pb or Sn as a main component laminated on the intermediate layer; A sliding member having a sliding member, wherein the adhesive layer on the second axial end face of the metal member extends continuously to further cover the inner and outer circumferential surfaces of the metal member, and a ratio of a surface area of the adhesive layer covering the inner circumferential surface or the outer circumferential surface to a surface area of the inner circumferential surface or the outer circumferential surface is 30% or more.