Method for producing a component, in particular vehicle component, and correspondingly produced component

Abstract

The disclosure relates to a method for producing a component, in particular a vehicle component or an engine component, such as a piston of an internal combustion engine. The method comprises forming a first body region, in particular by means of casting or forging. The method includes forming a second body region, which is connected to the first body region, from an aluminium alloy or an iron-based alloy or a copper-based alloy by means of an additive manufacturing method. The second body region is alloyed in such a manner that it has higher thermal stability, higher mechanical strength or higher wear resistance upon tribological stressing than the first body region.

Claims

1. A method for producing a component, comprising: forming a first body region, and forming a second body region, which is connected to the first body region, from an aluminium alloy or an iron-based alloy or a copper-based alloy by means of an additive manufacturing method, wherein the second body region is alloyed in such a manner that the second body region has higher thermal stability, higher mechanical strength or higher wear resistance upon tribological stressing than the first body region.

2. The method according to claim 1, wherein: a metallic powder is fused in the additive manufacturing method in order to form the second body region, or a plurality of different metallic powders are fused in the additive manufacturing method in order to form the second body region.

3. The method according to claim 1, wherein: the second body region has a graded alloy content or is alloyed inhomogenously; or an alloy content of an alloy element or of a plurality of alloy elements changes in the second body region with increasing distance from the first body region or with decreasing distance from a component surface of the second body region.

4. The method according to claim 1, furthermore comprising: roughening a contact surface, which is to be connected to the second body region, of the first body region, or roughening a contact surface, which is to be connected to the first body region, of the second body region.

5. The method according to claim 4, wherein the roughening is by means of laser roughening or electron beam roughening.

6. The method according to claim 4, wherein: the roughening of the contact surface and the forming of the second body region are carried out in the same manufacturing plant.

7. The method according to claim 1, wherein: the second body region has higher thermal stability or higher mechanical strength or higher wear resistance upon tribological stressing than the first body region by formation of a multiplicity of distributed heat-resistant or wear-reducing phases in the second body region by the additive manufacturing method; or the second body region has higher thermal stability or higher mechanical strength or higher wear resistance upon tribological stressing than the first body region by means of a higher content of alloy elements than the first body region.

8. The method according to claim 1, wherein: the second body region has a thermally or mechanically stressed component surface of the component.

9. The method according claim 1, wherein: the first body region is formed from steel or an aluminium alloy.

10. The method according claim 1, wherein: the first body region is a piston blank of a piston of an internal combustion engine; or the second body region has at least one portion of a piston head of a piston.

11. The method according to claim 10, wherein the at least one portion of the piston head of the piston is a depression edge of the piston head.

12. The method according to claim 1, wherein: the second body region is in the form of a coating; or the second body region has a material thickness which is less than a material thickness of the first body region or is less than 20 mm.

13. The method according to claim 1, wherein: the second body region is built up directly on the first body region; or the second body region after its production is connected to the first body region by one or more of friction welding, induction welding, laser welding or a hybrid welding method.

14. The method according to claim 1, wherein: the additive manufacturing method is a powder bed method and a fusing of a metallic powder or of a plurality of different metallic powders uses an electron beam or a laser beam.

15. The method according to claim 1, wherein: an alloy content of Mg, Si or Cu is reduced in the second body region with increasing distance from the first body region or with decreasing distance from the component surface of the second body region; or an alloy content of Ni, Fe, Mn, Zr, V, Ti, Nb, Sc, Mo, Co, Cr, Hf, Ta, W, Re, Al, P or Si is increased in the second body region with increasing distance from the first body region or with decreasing distance from the component surface of the second body region.

16. The method according to claim 1, furthermore comprising: heating or cooling the component before, during, or after the formation of the second body region; or heat treating the component after the formation of the second body region.

17. The method according to claim 1, wherein the component is a vehicle component, an engine component, or a piston.

18. The method according to claim 1, wherein the first body region is formed by casting or forging.

19. The method according to claim 1, wherein: the second body region has higher thermal stability or higher mechanical strength at homologous temperatures of greater than or equal to 0.5 than the first body region by means of a higher content of alloy elements than the first body region.

20. The method according to claim 1, wherein: the second body region has a material thickness which is greater than 0.3 mm.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The previously described embodiments and features of the disclosure can be combined with one another as desired. Further details and advantages of the disclosure will be described below with reference to the attached drawings, in which:

(2) FIG. 1 shows a portion of an exemplary piston upper part of a piston of a reciprocating piston internal combustion engine according to the present disclosure;

(3) FIG. 2 shows a portion of an exemplary first and second body region of a vehicle component according to the present disclosure; and

(4) FIG. 3 shows a portion of a further exemplary first and second body region of a vehicle component according to the present disclosure.

(5) The embodiments shown in the figures at least partially corresponds, and therefore similar or identical parts are provided with the same reference signs and reference is also made for the explanation thereof to the description of the other embodiments or figures in order to avoid repetitions.

DETAILED DESCRIPTION

(6) FIG. 1 shows a piston upper part of a piston 10 of an internal combustion engine, for example of a motor vehicle. The piston 10 herein is described as a exemplary embodiment for the production method according to the disclosure. However, it is also possible to produce other components, such as, for example, other engine components of an internal combustion engine or components of a turbine, according to the method according of the disclosure. In particular, components which have a component surface which is thermally and/or mechanically (greatly) stressed during operation are suitable for the method according to the disclosure. The vehicle component can be a component of a motor vehicle, in particular of a utility vehicle, for example of a bus or of a lorry.

(7) The piston 10 can be produced integrally as one piece as what is referred to as a monoblock. Alternatively, the piston 10 can be built up in multiple parts, wherein the plurality of parts are connected to one another, for example, by means of releasable or non-releasable connecting means.

(8) The piston 10 is formed from a first body region 12 and a second body region 14. Only part of the first body region 12 is illustrated. The first body region 12 is formed by a piston blank. The second body region 14 comprises at least one portion of a piston head 16 of the piston 10. In the embodiment illustrated, the second body region 14 is substantially provided in the region of a depression edge 18 of the piston head 16. The second body region 14 extends annularly. It is also possible for the body region 14 to extend, for example, in a planar manner. The second body region 14 is arranged, for example symmetrically about a centre longitudinal axis of the piston 10. During the operation of the internal combustion engine, the depression edge 18, in particular, is exposed to high thermal loadings. The piston 10 on account of its production method is capable of withstanding the high thermal loadings in particular in the region of the piston head 16 during the operation. The piston 10 can nevertheless be used in practice since the outlay and the costs for the production of the piston 10 are kept within economically adjustable extents.

(9) The first body region 12 forms a main body region while the second body region 14 only forms a partial body region, in particular an edge body region. The first body region 12 is directly connected to the second body region 14. In particular, the first body region 12 merges into the second body region 14. The second body region 14 has a smaller material thickness than the first body region 12. In particular, a material thickness of the second body region 14 is less than 20 mm. For example, the second body region 14 can be in the form of a coating of the first body region 12.

(10) The method for producing the piston 10 is designed as a hybrid method. The first body region 12 and the second body region 14 are produced by different manufacturing methods.

(11) The first body region 12 is produced by means of a conventional manufacturing method, for example casting or forging. The first body region 12 is produced from a basic material, in particular from steel or an aluminium alloy. The first body region 12 can therefore be formed comparatively cost-effectively.

(12) The second body region 14 is produced, in particular layer by layer, by means of an additive manufacturing method. The second body region 14 is composed of an aluminium alloy. It is also possible for the second body region to be composed of an iron-based alloy (for example steel, cast iron alloy) or a copper-based alloy. The second body region 14 is alloyed in such a manner than the second body region 14 has greater thermal stability or heat resistance than the first body region 12. The second body region 14 can have an increased content of alloy elements. In particular, the additive manufacturing method permits the formation of a plurality of, in particular very finely, distributed heat-resistant phases or precipitations which lead to great thermal stability of the second body region 14. In particular, by means of the additive manufacturing method, the second body region 14 by formation of the multiplicity of heat-resistant phases can achieve thermal stability and/or mechanical strength of a magnitude that would not be possible by means of a conventional manufacturing method which is used for producing the first body region 12.

(13) By means of the conventional production method, the first body region 12 is produced separately from the second body region 14. The second body region 14 can be produced separately from the first body region 12. The second body region 14 after its production can then be fixedly connected to the first body region 12, in particular by friction welding or laser welding. However, it is also possible for the second body region 14 to be built up directly onto the first body region 12. Before, during or after the second body region 14 is grown on/built up, the first body region 12 can be connected to other, for example, conventionally manufactured component regions. The connection can be produced, for example, by friction welding, induction welding, laser welding or a hybrid welding method.

(14) In order to produce the second body region 14, a metallic powder or a plurality of different metallic powders are fused, for example, in a powder bed method. For example, the first body region 12 which is in the form of a piston blank can be positioned in a plant for additive manufacturing. The second body region 14 is then built up directly on the first body region 12 by fusing of the metallic powder or of the metallic powders. The fusing of the metallic powder can take place, for example, by means of electron beam or laser beam. The additive production method can comprise, for example, laser sintering or laser melting.

(15) The surface of the second body region 14, in particular, is exposed to high thermal and/or mechanical loadings. The thermal loadings can be smaller in the direction of the piston interior. It can therefore be provided, for example, that the second body region 14 has a gradation of alloy elements. Put in other words, the second body region 14 can have a changing (for example increasing or decreasing) content of alloy elements with a changing distance from its surface. By means of the gradation, it is possible, for example, by means of a comparatively high or low content of certain alloy elements in the region of the surface, for particularly high thermal stability and high mechanical strength to be achieved at low and high homologous temperatures in this region.

(16) For example, an alloy content of Mg, Si and/or Cu can be reduced in the second body region 14 with increasing distance from the first body region 12 and/or with decreasing distance from the surface of the second body region 14. It is also possible, for example, for an alloy content of Ni, Fe, Mn, Zr, V, Ti, Nb, Sc, Mo, Co, Cr, Hf, Ta, W, Re, Al, P and/or Si to be increased in the second body region 14 with increasing distance from the first body region 12 and/or with decreasing distance from the surface of the second body region 14.

(17) FIG. 2 illustrates a contact surface 20 of the first body region 12 and of the second body region 14. At the contact surface 20, the first body region 12 and the second body region 14 are in contact when they have been or are connected to each other. In particular, it is shown in FIG. 2 that the contact surface 20 of the first body region 12 and/or of the second body region 14 can be roughened in order to permit a fixed connection between the first body region 12 and the second body region 14 and/or to increase the adhesive strength of the connection. The contact surface 20 of the first body region 12 is expediently roughened when the second body region 14 is built up directly on the first body region 12. In this case, the contact surface 20 is roughened before the second body region 14 is built up. In another case in which the second body region 14 is initially produced separately in order to be subsequently connected to the first body region 12, additionally or alternatively, however, the contact surface 20 of the second body region 14 can also be roughened.

(18) The contact surface 20 may be roughened by means of laser beam or electron beam. It is possible for the roughening of the contact surface 20 to take place in the same manufacturing plant as the production of the second body region 14.

(19) It is also possible to improve the properties of the piston 10, in particular of the second body region 14, by targeted cooling and/or heating before, during or after production. Heat treatment can expediently also be undertaken after the production of the piston 10.

(20) FIG. 3 shows a further exemplary embodiment. The second body region 14 is provided here in a planar manner in the region of the depression edge 18 and of the piston head 16 (including the depression and the central dome) of the piston 10. Put in other words, the second body region 14 entirely comprises a combustion surface of the piston 10 that faces the combustion chamber.

(21) The disclosure is not restricted to the exemplary embodiments described above. On the contrary, a multiplicity of variants and modifications are possible which likewise make use of the inventive concept and therefore fall within the scope of protection.

LIST OF REFERENCE SIGNS

(22) 10 Piston 12 First body region 14 Second body region 16 Piston head 18 Depression edge 20 Contact surface