COMPONENT, IN PARTICULAR FOR A VALVE TRAIN SYSTEM, AND METHOD FOR PRODUCING A COMPONENT OF THIS TYPE

Abstract

A component (100), in particular for a valve train system, having a substrate (3) and a layer system (1) applied at least in parts to the substrate (3), wherein the layer system (1) includes a friction-reducing and wear-reducing protective layer (2) for forming a component surface, wherein the protective layer (2) has at least one first sub-layer (4, 4a) made of doped tetrahedral amorphous carbon, which includes sp.sup.3-hybridized carbon having a mole fraction of at least 50%, wherein the first sub-layer (4, 4a) contains oxygen in a concentration in the range from 0.1 at % to 3.0 at % and hydrogen in a concentration in the range from 0.1 at % to 15 at %, and wherein the first sub-layer (4, 4a) has one or more of the following dopants in a concentration in the range from 0.03 at % to 15 at %: chromium, molybdenum, tungsten, silicon, copper, niobium, zirconium, vanadium, nickel, iron, silver, hafnium, fluorine, boron and nitrogen. A method for producing such a component (100) is also provided.

Claims

1. A component, comprising: a substrate; a layer system applied at least in parts to the substrate; wherein the layer system comprises a friction-reducing and wear-reducing protective layer that forms a component surface, the protective layer has a first sub-layer made of: doped tetrahedral amorphous carbon which comprises sp.sup.3-hybridized carbon having a mole fraction of at least 50%, oxygen in a concentration in a range from 0.1 at % to 3.0 at %, hydrogen in a concentration in a range from 0.1 at % to 15 at %, and one or more of the following dopants in a concentration in a range from 0.03 at % to 15 at %: chromium, molybdenum, tungsten, silicon, copper, niobium, zirconium, vanadium, nickel, iron, silver, hafnium, fluorine, boron or nitrogen.

2. The component according to claim 1, wherein the layer system has an adhesive layer arranged between the substrate and the protective layer, and the adhesive layer has at least one of chromium, titanium, tungsten, zirconium, molybdenum, chromium nitride, titanium nitride, tungsten nitride, molybdenum nitride, or zirconium nitride.

3. The component according to claim 2, wherein the adhesive layer has a layer thickness in a range from 0.001 μm to 2.0 μm.

4. The component according to claim 2, wherein the layer system has an intermediate layer arranged between the adhesive layer and the protective layer, and the intermediate layer has at least one of a carbide, carbonitride of a metal or transition metal, or a non-metal.

5. The component according to claim 4, wherein the intermediate layer has a layer thickness in a range from 0.001 μm to 1.0 μm.

6. The component according to claim 1, wherein the protective layer has one or more of the first sub-layers made of the doped tetrahedral amorphous carbon and further includes one or more second sub-layers made of undoped tetrahedral amorphous carbon, and the first and the second sub-layers alternate with one another.

7. The component according to claim 1, wherein the protective layer has a hardness which is greater than 40 GPa.

8. The component according to claim 1, wherein the component is a sliding bearing component or a roller bearing component or a component of a finger follower or a rocker arm or a pump tappet or a roller tappet.

9. The component according to claim 8, wherein the layer system is arranged in at least one of a rolling contact, an anti-friction contact, or a sliding contact to an adjacent contact component.

10. A method for producing a component according claim 1, the method comprising applying the first sub-layer made of the doped tetrahedral amorphous carbon by physical vapor deposition using at least one of an arc evaporation or high-power impulse magnetron sputtering, and introducing the at least one dopant into the at least one first sub-layer via at least one of a gas phase, a target made of doped carbon, or co-sputtering into the first sub-layer.

11. A valve train system component, comprising: a substrate; a layer system applied at least in parts to the substrate; wherein the layer system comprises a friction-reducing and wear-reducing protective layer that forms a component surface, the protective layer has a first sub-layer made of: doped tetrahedral amorphous carbon which comprises sp.sup.3-hybridized carbon having a mole fraction of at least 50%, oxygen in a concentration in a range from 0.1 at % to 3.0 at %, hydrogen in a concentration in a range from 0.1 at % to 15 at %, and one or more of the following dopants in a concentration in a range from 0.03 at % to 15 at %: chromium, molybdenum, tungsten, silicon, copper, niobium, zirconium, vanadium, nickel, iron, silver, hafnium, fluorine, boron or nitrogen.

12. The valve train system component according to claim 11, wherein the layer system has an adhesive layer arranged between the substrate and the protective layer, and the adhesive layer has at least one of chromium, titanium, tungsten, zirconium, molybdenum, chromium nitride, titanium nitride, tungsten nitride, molybdenum nitride, or zirconium nitride.

13. The valve train system component according to claim 12, wherein the adhesive layer has a layer thickness in a range from 0.001 μm to 2.0 μm.

14. The valve train system component according to claim 12, wherein the layer system has an intermediate layer arranged between the adhesive layer and the protective layer, and the intermediate layer has at least one of a carbide, carbonitride of a metal or transition metal, or a non-metal.

15. The valve train system component according to claim 14, wherein the intermediate layer has a layer thickness in a range from 0.001 μm to 1.0 μm.

16. The valve train system component according to claim 11, wherein the protective layer has one or more of the first sub-layers made of the doped tetrahedral amorphous carbon and further includes one or more second sub-layers made of undoped tetrahedral amorphous carbon, and the first and the second sub-layers alternate with one another.

17. The valve train system component according to claim 11, wherein the protective layer has a hardness which is greater than 40 GPa.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Further details and advantages will be explained below with reference to the exemplary embodiment shown in the drawings. In the figures:

[0025] FIG. 1A shows an exemplary embodiment of a component according to the disclosure with a layer system on a substrate in a schematic representation;

[0026] FIG. 1B shows an exemplary embodiment of a component according to the disclosure with a layer system on a substrate in a schematic representation;

[0027] FIG. 2A shows an exemplary embodiment of a component according to the disclosure with a layer system comprising an adhesive layer on a substrate in a schematic representation;

[0028] FIG. 2B shows an exemplary embodiment of a component according to the disclosure with a layer system comprising an adhesive layer on a substrate in a schematic representation;

[0029] FIG. 3A shows an exemplary embodiment of a component according to the disclosure with a layer system comprising an intermediate layer on a substrate in a schematic representation;

[0030] FIG. 3B shows an exemplary embodiment of a component according to the disclosure with a layer system comprising an intermediate layer on a substrate in a schematic representation;

[0031] FIG. 4A shows an exemplary embodiment of a component according to the disclosure with a layer system comprising an adhesive layer and an intermediate layer on a substrate in a schematic representation;

[0032] FIG. 4B shows an exemplary embodiment of a component according to the disclosure with a layer system comprising an adhesive layer and an intermediate layer on a substrate in a schematic representation;

[0033] FIG. 5 shows an exemplary embodiment of a component according to the disclosure in the form of a rolling element in a schematic representation.

DETAILED DESCRIPTION

[0034] In the exemplary embodiment shown in FIG. 1A of a component 100 according to the disclosure having a layer system 1, this consists of the protective layer 2, which is formed from a single homogeneous first sub-layer 4 of doped tetrahedral amorphous carbon, which is directly applied to a substrate 3.

[0035] In the exemplary embodiment shown in FIG. 1B, the component 100 comprises a protective layer 2, which is formed from a sequence of a plurality of first sub-layers 4a and second sub-layers 5, wherein a first sub-layer 4a made of a doped tetrahedral amorphous carbon is first applied directly to the substrate 3, on which in turn a second sub-layer 5 made of an undoped tetrahedral amorphous carbon is arranged. The alternation of doped first sub-layers 4a and undoped second sub-layers 5 continues up to the top second sub-layer 5.

[0036] The layer systems 1 shown here and in FIGS. 2B, 3B and 4B are exemplary representations. The sequence of doped first sub-layers 4a and undoped second sub-layers 5 can in principle contain any number of first sub-layers 4a and second sub-layers 5.

[0037] In the exemplary embodiment of a component 100 shown in FIG. 2A, an adhesive layer 6 is arranged between the substrate 3 and the protective layer 2, which improves the binding of the protective layer 2 to the substrate 3 and, together with the protective layer 2, forms the layer system 1.

[0038] In the exemplary embodiment of a component 100 shown in FIG. 2B, there is an adhesive layer 6 arranged between the protective layer 2, which comprises an alternating sequence of first sub-layers 4a made of a doped tetrahedral amorphous carbon and of second sub-layers 5 made of an undoped tetrahedral amorphous carbon, and the substrate 3.

[0039] In the exemplary embodiment of a component 100 shown in FIG. 3A, an intermediate layer 7, which together with the protective layer 2 forms the layer system 1, is arranged between a substrate 3 and the protective layer 2 comprising only a first sub-layer 4a made of doped tetrahedral amorphous carbon.

[0040] In the exemplary embodiment of a component 100 shown in FIG. 3B, an intermediate layer 7 is arranged between a protective layer 2, which has an alternating sequence of first sub-layers 4a made of a doped tetrahedral amorphous carbon and of second sub-layers 5 made of an undoped tetrahedral amorphous carbon, and together with the first sub-layers 4a and the second sub-layers 5 forms the layer system 1 applied to the substrate 3.

[0041] In the exemplary embodiment of a component 100 shown in FIG. 4A, an adhesive layer 6 and an intermediate layer 7 are arranged between the substrate 3 and the protective layer 2 in the form of a first sub-layer 4 made of doped tetrahedral amorphous carbon, and together with the protective layer 2 form the layer system 1. The adhesive layer 6 improves the binding of the intermediate layer 7 to the substrate 3, while the intermediate layer 7 in turn functions as an adhesion promoter between the adhesive layer 6 and the protective layer 2. During the manufacturing process, the intermediate layer 7 can either be deposited separately after the adhesive layer 6 and before the protective layer 2 or, for example, can be formed by a reaction between the adhesive layer 6 and the protective layer 2 or by an implantation of carbon into the adhesive layer 6.

[0042] In the exemplary embodiment of a component 100 shown in FIG. 4B, an adhesive layer 6 and an intermediate layer are arranged between the protective layer 2, which has an alternating sequence of first sub-layers 4a made of a doped tetrahedral amorphous carbon and of second sub-layers 5 made of an undoped tetrahedral amorphous carbon 7, and, similarly to FIG. 4A, improve the binding to the substrate 3.

[0043] When the component 100 shown in FIG. 5 is in the form of a rolling element 8, the running surface 9 of the rolling element 8 is provided with a layer system 1 to utilize the friction-reducing and wear-reducing properties of the protective layer 2 for use of the rolling element 8 as part of a valve control of an internal combustion engine. Optionally, the side surfaces 10, 11 of the rolling element 8 can also be provided with the layer system 1.

[0044] The rolling element 8 described above is in particular a cam roller 8, wherein an embodiment of the layer system 1 is formed on the running surface 9 of the rolling element 8 and/or on one or more side surfaces 10, 11 of the rolling element 8.

[0045] The components 100 described above and the rolling element 8 described above can be produced with an embodiment of the method according to the disclosure, in which a protective layer 2 comprising at least one first sub-layer 4a of doped tetrahedral amorphous carbon is applied to a substrate 3 or the running surface 9 and/or the side surfaces 10, 11, wherein the protective layer 2 is applied by physical vapor deposition by means of arc evaporation and/or high-power impulse magnetron sputtering, wherein at least one dopant is introduced into the at least one first sub-layer 4a via a gas phase and/or a target made of doped carbon is used and/or the at least one dopant is introduced into the at least one first sub-layer 4a by co-sputtering.

LIST OF REFERENCE SIGNS

[0046] 1 Layer system [0047] 2 Protective layer [0048] 3 Substrate [0049] 4, 4a First sub-layer made of doped tetrahedral amorphous carbon [0050] 5 Second sub-layer made of undoped tetrahedral amorphous carbon [0051] 6 Adhesive layer [0052] 7 Intermediate layer [0053] 8 Rolling element [0054] 9 Running surface [0055] 10 First side surface [0056] 11 Second side surface [0057] 100 Component