COMPOSITE MATERIAL FOR A SLIDING BEARING

Abstract

The invention relates to a method for producing a sliding bearing composite material (10), having a support layer (14), in particular made of steel, a bearing metal layer (18) made of a lead-free aluminum base alloy containing magnesium, and a running layer (22), wherein the aluminum base alloy ultimately comprises 0.5-5.5% by weight magnesium, optionally one or more alloy components from the group comprising zinc, copper, silicon, iron, manganese, chromium, titanium, zirconium, vanadium, nickel, cobalt, cerium, and alloy components resulting from impurities, the sum of the latter not exceeding 1% by weight, and the remainder being aluminum, wherein the aluminum base alloy is copper-free or contains at most 3% by weight copper, the total content of zinc, copper, and nickel does not exceed 8% by weight, and the total content of all alloy components does not exceed 12% by weight. The bearing metal layer (18) is either rolled directly onto the support layer (14) or roll-cladded beforehand with an intermediate layer (38) made of an aluminum alloy or technical pure aluminum and then rolled onto the support layer (14) with this intermediate layer (38) in between, in such a way that the intermediate layer (38) subsequently has a thickness of at most 100 m, in particular at most 50 m, wherein the composite of the support layer (14) and the bearing metal layer (18) thus obtained is soft-annealed at temperatures between 280 and 350 C. for 2 to 10 hours so that the bearing metal layer of the composite has a Brinell hardness of 50-80 HB 1/5/30. The running layer (22) is subsequently applied galvanically or by means of a PVD method to the bearing metal layer (18).

Claims

1. A method for producing a sliding bearing composite material, having a support layer, in particular made of steel, a bearing metal layer made of a lead-free aluminum base alloy containing magnesium, and a running layer, wherein the aluminum base alloy ultimately comprises 0.5-5.5% by weight magnesium, one or more alloy components from the group comprising zinc, copper, silicon, iron, manganese, chromium, titanium, zirconium, vanadium, nickel, cobalt, cerium, and alloy components resulting from impurities, the sum of the latter not exceeding 1% by weight, and the remainder being aluminum, wherein the aluminum base alloy is copper-free or contains at most 3% by weight copper, the total content of zinc, copper, and nickel does not exceed 8% by weight, and the total content of all alloy components does not exceed 12% by weight, wherein the bearing metal layer is either rolled directly onto the support layer or roll-cladded beforehand with an intermediate layer made of an aluminum alloy or technical pure aluminum and is then rolled onto the support layer, with this intermediate layer in between, in such a way that the intermediate layer subsequently has a thickness of at most 100 m, in particular at most 50 m, wherein the composite of the support layer and the bearing metal layer thus obtained is soft-annealed at temperatures between 280 and 350 C. for 2 to 10 hours so that the bearing metal layer of the composite has a Brinell hardness of 50-80 HB 1/5/30, and the running layer is subsequently applied galvanically or by means of a PVD method to the bearing metal layer.

2. The method according to claim 1, characterized in that the aluminum base alloy comprises one or more of the following alloy components: 0.05-7.5% by weight zinc, up to 3% by weight copper, 0.05-6% by weight silicon, 0.05-0.5% by weight iron, 0.05-1% by weight manganese, 0.05-1% by weight chromium, 0.05-0.5% by weight titanium, 0.05-0.5% by weight zirconium, 0.05-0.5% by weight vanadium, 0.1-3% by weight nickel, 0.1-1% by weight cobalt, and/or 0.05-0.5% by weight cerium.

3. The method according to claim 1, characterized in that the aluminum base alloy comprises 1.5-5.5% by weight, in particular 2.0-5.5% by weight, magnesium.

4. The method according to claim 1, characterized in that the aluminum base alloy is an AlMg(2-3) alloy or an AlMg(3-4) alloy or an AlMg(4-) alloy, containing 0.15-0.35% by weight Cr and/or 0.2-0.5% by weight Mn, containing further alloy components that do not exceed 1% in sum.

5. The method according to claim 1, characterized in that the running layer is a layer that is applied by means of a PVD method, and that is formed on an Al basis with 5-40% by weight tin and optionally includes 0.1-5% by weight copper, 0.1-6% by weight silicon, 0.05-1% by weight manganese, 0.05-1% by weight chromium, 0.05-0.5% by weight titanium, 0.05-0.5% by weight zirconium, 0.05-0.5% by weight vanadium, 0.1-3% by weight nickel, 0.1-1% by weight cobalt, and/or 0.05-0.5% by weight cerium.

6. The method according to claim 5, characterized in that the running layer is formed by an AlSn(18-27)Cu(0.5-3) alloy, in particular an AlSn(20)Cu(1) alloy or an AlSn(25)Cu(2.5) alloy.

7. The method according to claim 5, characterized in that a further layer made of an aluminum base alloy or a copper, cobalt, or nickel base alloy and applied by means of a PVD method is situated between the running layer (22) and the bearing metal layer.

8. The method according to one or more of preceding claim 1, characterized in that the running layer is a galvanically deposited layer made of bismuth or a bismuth alloy, or tin or a tin-copper alloy, in particular a SnCu(4-8) alloy, in particular a SnCu(6) alloy.

9. The method according to claim 8, characterized in that a first intermediate layer based on nickel, copper, or cobalt is situated between the running layer and the bearing metal layer.

10. The sliding bearing composite material according to claim 9, characterized in that a second intermediate layer based on tin-nickel or tin-copper or tin-cobalt is situated between the running layer and the first intermediate layer.

11. The method according to one or more of the preceding claims, characterized in that the thickness of the running layer is at most 30 m, in particular at most 25 m, in particular at most 20 m, and at least 5 m, in particular at least 10 m, in particular 10 m.

12. A sliding bearing composite material produced by a method according to claim 1, having a support layer, in particular made of steel, a bearing metal layer made of a lead-free aluminum base alloy containing magnesium, and a running layer, wherein the aluminum base alloy comprises 0.5-5.5% by weight magnesium and optionally one or more alloy components selected from the group comprising zinc, copper, silicon, iron, manganese, chromium, titanium, zirconium, vanadium, nickel, cobalt, cerium, and alloy components resulting from impurities, the sum of the latter not exceeding 1% by weight, wherein the aluminum base alloy is copper-free or contains at most 3% by weight copper, and the total content of zinc, copper, and nickel does not exceed 8% by weight and the total content of all alloy components does not exceed 12% by weight, wherein the bearing metal layer is rolled onto the support layer, either directly or with an intermediate layer, made of an aluminum alloy or technical pure aluminum and having a thickness of at most 100 m, in particular at most 50 m, in between, wherein the composite of the support layer and the bearing metal layer (18) thus obtained is soft-annealed at temperatures between 280 and 350 C. for 2 to 10 hours so that the bearing metal layer of the composite has a Brinell hardness of 50-80 HB 1/5/30, and the running layer (22) is subsequently applied galvanically or by means of a PVD method to the bearing metal layer (18).

13. A sliding bearing element, in particular a sliding bearing shell, in particular a crankshaft bearing shell or connecting rod bearing shell, characterized in that it includes a sliding bearing composite material according to claim 12.

Description

[0026] The drawings show the following:

[0027] FIG. 1 shows a schematic sectional view, not true to scale, of a sliding bearing composite material according to the invention;

[0028] FIG. 2 shows a schematic sectional view, not true to scale, of another embodiment of a sliding bearing composite material according to the invention;

[0029] FIG. 3 shows a schematic sectional view, not true to scale, of another embodiment of a sliding bearing composite material according to the invention; and

[0030] FIG. 4 shows a schematic sectional view, not true to scale, of a connecting rod bearing shell that includes a sliding bearing composite material according to the invention.

[0031] FIG. 1 shows a schematic sectional view, not true to scale, of a sliding bearing composite material 10 according to the invention for the manufacture of sliding bearing elements, in particular sliding bearing shells, in a bending process. The sliding bearing composite material 10 comprises a support layer 14 preferably made of steel. A bearing metal layer 18 having the composition stated in the introduction to the description is rolled on, i.e., applied in a roll cladding method, on a side of the support layer 14 facing a sliding partner. A thin running layer 22 having the composition and thickness stated in the introduction to the description is applied galvanically or by a PVD method to the bearing metal layer 18.

[0032] FIG. 2 shows a schematic sectional view, not true to scale, of a sliding bearing composite material 10 according to the invention. In the exemplary embodiment shown in FIG. 2, the running layer 22 is designed as a galvanically deposited layer. In this exemplary embodiment, a first intermediate layer 26 having the composition stated in the introduction to the description is situated between the bearing metal layer 18 and the running layer 22. A second intermediate layer 30 having the composition stated in the introduction to the description is situated between the first intermediate layer 26 and the running layer 22. Both intermediate layers are galvanically applied, and have a small thickness of preferably only 1-4 m.

[0033] FIG. 3 shows a schematically illustrated sectional view, not true to scale, of a sliding bearing composite material 10 according to the invention. In the exemplary embodiment shown in FIG. 3, the running layer 22 is designed as a layer that has the composition stated in the introduction to the description and that is applied by a PVD method, typically sputtered. A further layer 34 that has the composition stated in the introduction to the description and that is applied by means of a PVD method is situated between the running layer 22 and the bearing metal layer 18.

[0034] An intermediate layer 38 is situated between the bearing metal layer 18 and the support layer 14. In this exemplary embodiment, the intermediate layer 38 is designed in the form of an aluminum alloy, but within the meaning of the invention may also be made of pure aluminum. A layered structure having no intermediate layer 38 is likewise within the meaning of the invention. For the manufacture, the bearing metal layer 18 and the intermediate layer 38 are roll-cladded to one another. The composite made up of the bearing metal layer 18 and the intermediate layer 38 is subsequently cladded onto the support layer 14, which is easily possible due to the fact that the intermediate layer 38 is softer than the bearing metal layer 18.

[0035] In the exemplary embodiments shown in FIGS. 1 through 3, in each case the bearing metal layer 18 with its composition according to the invention forms a solid base with only moderate hardness for the running layer 22. This composite allows high load on the running layer 22, at the same time with a long service life of the sliding bearing composite material 10.

[0036] FIG. 4 shows a schematically illustrated sectional view, not true to scale, of a sliding bearing shell 42 according to the invention. Such a sliding bearing shell may be manufactured from the sliding bearing composite material according to the invention 10 by means of roll bending, for example.