METHOD FOR PRODUCING A SHAPED PART, AND A SHAPED PART

Abstract

A method for producing a shaped part may include providing a first layer consisting of a first sheet metal material and at least a second layer consisting of a second sheet metal material, forming a preliminary composite comprising the first layer and the at least second layer, plating the preliminary composite, and forming the preliminary composite to obtain the shaped part using a flow turning, compression or deep drawing method. The plating may be done before or during the forming process. At least one of the first layer or the second layer may be heated for the plating and/or the forming. The shaped part may be formed by compressing the preliminary composite with a pressing body, and the pressing body may be moved parallel or perpendicular to an axis of symmetry during the compression.”

Description

PRIOR ART

The invention relates to a method for producing a shaped part, and to a shaped part.

In particular, the present invention relates to a method in which a material sequence in the shaped part is deliberately assembled by plating. Plating typically ensures that a first layer or a base body is covered by at least a second layer of another material by creating an integrally bonded composite between the first and the at least second layer by a mechanical action, such as a rolling treatment. It is therefore usually intended to cover a base body with a more valuable material than the base body or—as is disclosed for example in the publication DE 10 2012 100 278 A1—to create in the fabricated shaped part a material progression with different physical properties. The shaped part formed from a band, in which the desired integrally bonded composite between the first and the second layer was created in advance by a costly plating of slabs and hot rolling, is processed such that the desired material progression emerges in the fabricated shaped part.

DISCLOSURE OF THE INVENTION

One problem which the present invention proposes to solve is to provide a method with which the production of shaped parts consisting of several layers is simplified and, in particular, individualized.

The present invention solves the problem by a method for producing a shaped part having the following method steps:

• • providing a first layer consisting of a first sheet metal material and at least a second layer consisting of a second sheet metal material,
  • forming a preliminary composite comprising the first layer and the at least second layer
  • plating the preliminary composite
  • forming the preliminary composite to obtain the shaped part using a flow turning, compression or deep drawing method,

wherein the plating is done before or during the forming process.

As compared to the prior art, with the method according to the invention the plating and the forming of sheet metal materials are done in a joint work step or alternatively a plating of sheet metal materials is done without having to perform the costly hot rolling process of slabs and a separate forming is done. In this way, a fabrication of the shaped part is not only made faster, but also the shaped part can be individualized more easily. Finally, one is not bound by the arrangements dictated in the coil or the thickness relationships of the first and at least second layer used there. Instead, depending on the intended purpose of the desired shaped part, the first layer and at least second layer of sheet metal materials can be correspondingly provided individually, for example in regard to their thickness.

Preferably, the forming is done by a projecting, flow turning and/or compression. For example, the forming produces a hub, for example, for the fabricated component. It is provided in particular that the first and the at least second layer of sheet metal materials are laid against one another or on top of one another in the preliminary composite, without there being present a relatively large-area integrally bonded connection. It is conceivable that the first and/or the at least second layer of sheet metal materials are formed such that in addition to the integrally bonded connection the forming realizes a form fit between the first and the second layer. In particular, it is provided that forming and plating are carried out simultaneously in a joint, preferably separate, work step. Alternatively, prior to the forming by a deep drawing, projecting, flow turning and/or compression, a first and at least second layer of sheet metal materials are laid against or on top of one another, being integrally bonded to each other by plating.

Advantageous embodiments and modifications of the invention will be found in the dependent claims and the description making reference to the drawings.

According to another embodiment of the present invention, it is provided that the first layer and/or the at least second layer of sheet metal materials are heated for the plating. It is also conceivable that the plating is done without prior heating, i.e., in the cold state. Furthermore, it is conceivable that the first and/or at least second layer of sheet metal materials is heated specifically in particular ranges. Thanks to the heating, the forming and plating or only the plating can be advantageously facilitated.

According to another embodiment of the present invention, it is provided that a shaped part is formed which is entirely rotationally symmetrical to an axis of symmetry. It is also conceivable that only a partial region of the shaped part has a rotationally symmetrical region. Furthermore, it is conceivable that a rotationally asymmetrical shaped part is formed by nonround compression. In nonround compression, for example, a rotationally asymmetrical shaped part is realized by a force- or path-controlled feeding of the pressing roller.

According to another embodiment of the present invention, it is provided that a pressing body, such as a pressing roller, is used during the compression method, the pressing body being moved parallel and/or perpendicular to the planned axis of symmetry during the compression method. In particular, the pressing body during the forming process lies against the preliminary composite, and by moving the pressing body the forming essential for the forming of the planned shaped part is realized. Preferably, the first and/or at least second layer of sheet metal materials is realized by several pressing bodies, for example pressing bodies situated opposite each other. For example, the pressing body has a discus-shaped base body, whose closing edge comes into contact with the first and/or at least second layer of sheet metal materials during the compression method.

According to another embodiment of the present invention, it is provided that a second sheet metal material is used which is different from the first sheet metal material, in particular an iron material being used as the first sheet metal material and at least second sheet metal material or a nonferrous material being used as the first sheet metal material and as the second sheet metal material. It is conceivable that the iron material used as the second sheet metal material is different from the iron material used as the first sheet metal material in terms of physical properties, such as ductility, hardness, or shaping ability. For example, the first sheet metal material and the at least second sheet metal material differ in terms of carbon content. Preferably, the first layer of the sheet metal material comprises an iron material with a carbon fraction of more than 0.1 wt. %, preferably more than 0.25 wt. % and especially preferably approximately 0.5 wt. %. In this way, a shaped part can be realized whose interior sheet metal material composition ensures for example a comparatively high hardness, while the exterior sheet metal material composition has a lower carbon fraction as compared to the interior sheet metal material composition and thus may provide a greater ductility.

According to another embodiment of the present invention, it is provided that

• • the first layer comprises an iron material and the at least second layer a nonferrous material, or
  • the first layer comprises a nonferrous material and the at least second layer an iron material. In this way, the range of potential sheet metal material compositions in the fabricated shaped part can be enlarged advantageously.

According to another embodiment of the present invention, it is provided that the first layer and the at least second layer of sheet metal materials are secured for the plating and optionally the forming. For this, the first and/or the at least second layer are clamped for example in a device and/or the layers are pressed together. In this way, it is advantageously assured that the first and/or the second layer do not slip during the plating and optionally the forming. Preferably, an abutment or hold-down is used for the securing of the first and/or at least second layer of sheet metal materials. It is also conceivable that the first layer and the at least second layer are fixed to each other for example by a spot welding or clamping together to form the preliminary composite for transport and positioning purposes.

According to another embodiment of the present invention, it is provided that the preliminary composite is arranged in a die. Preferably, the die comprises a receiving region, inside which the preliminary composite is arranged for the plating and optionally at least partly for the forming. In particular, the die is designed such that it counteracts a sideways displacement of the preliminary composite during the processing.

According to another embodiment of the present invention, it is provided that the preliminary composite is clamped in the die by means of a spring element. By means of the springs, fixation can be provided in an advantageous manner. In this case, a spring force of the spring element is directed at the receiving region of the die. Preferably, the die comprises several spring elements, which are arranged and/or configured such that the preliminary composite is centered inside the die inside the receiving area by the spring elements. In addition, the spring elements can provide a resetting of the nonplated and possibly nonformed parts of the composite.

According to another embodiment of the present invention, it is provided that the preliminary composite for the plating and optionally for the forming is arranged in an at least partly contoured receiving region of the die. For example, the receiving region comprises a contoured bottom region, in order to advantageously provide a better intermeshing during the plating and optionally the forming.

According to another embodiment of the present invention, it is provided that the preliminary composite for the plating and the forming is arranged on a shape-determining tool body, such as a round blank. For example, an outer contour of the shape-determining tool body establishes the shape of a bulge or a cavity in the fabricated shaped part. Preferably, the preliminary composite is pressed by the pressing body against an outer side of the shape-determining tool body until the planned shaped part has been formed. It is preferably provided that the preliminary composite is arranged between the shape-determining tool body and an abutment or hold-down, the shape-determining tool body and/or the abutment or the hold-down being subjected to force so as to provide for a fixation of the preliminary composite.

Another subject of the present invention is a shaped part fabricated by a method according to the invention, wherein the first layer as sheet metal material comprises an iron material with a carbon fraction of more than 0.1 wt. %, preferably more than 0.25 wt. % and especially preferably substantially 0.5 wt. %.

As compared to the shaped parts of the prior art, it is possible to provide a relatively high hardness of the fabricated shaped part in an advantageous manner with the increased carbon fraction. Preferably, by the choice of the at least second layer with a lower carbon fraction than the first layer, one can realize a greater ductility in the fabricated shaped part, especially on its exterior. It is conceivable that the fabricated shaped part comprises a hollow body, whose inside comprises at least partly the first layer.

The invention is not confined to two layers of sheet metal materials.

According to another embodiment of the present invention, it is provided that the shaped part is a joint head.

Further details, features and benefits of the invention will emerge from the drawings, as well as the following description of preferred embodiments with the aid of the drawings. The drawings illustrate only sample embodiments of the invention, not limiting the idea of the invention.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a die suitable for a method for producing a shaped part according to a first sample embodiment of the present invention.

FIGS. 2a to d show schematically consecutive snapshots of the method for producing a shaped part according to a second sample embodiment of the present invention.

FIGS. 3a to e show schematically consecutive snapshots of a method for producing a shaped part according to a third sample embodiment of the present invention.

EMBODIMENTS OF THE INVENTION

In the different figures the same parts are always given the same reference numbers and therefore in general are also only designated or mentioned once in each case.

FIG. 1 shows a die 10 suitable for a method for producing a shaped part according to a first sample embodiment of the present invention. In particular, this involves a method in which a first layer 1 of a first sheet metal material is plated with a second layer 2 of a second sheet metal material, i.e., by mechanical action an integrally bonded covering of the first layer 1 with the second layer 2 is created. Preferably, the second sheet metal material is one which is more precious or valuable than the first sheet metal material, or a shaped part is to be realized having different physical properties on different levels. In order to produce the shaped part consisting of the first layer 1 and the second layer 2, it is provided that the plating, especially an integrally bonded assembling of the first and second layer 1 and 2 into a composite, accompanying the plating, occurs at first in a first work step. Not represented here, but familiar to the skilled person, there then occurs the forming of the composite, which occurs in a second, separate work step, the forming involving a compression or deep drawing method by which the form of the shaped part is realized. In this way, one may advantageously do without a costly hot rolling of slabs stacked on each other in order to initially produce a semi-finished product in advance. For the fixing of the first layer 1 and the second layer 2 of sheet metal materials during the plating, the die 10 is preferably provided, where the die 10 has a receiving region to receive a preliminary composite consisting of the first layer 1 and the second layer 2. In particular, the die 10 comprises several spring elements 12, with which the first layer 1 and the second layer 2 are clamped in the die 10. In the sample embodiment represented in FIG. 1, spring elements 12 are arranged on an inner side 11′ of the receiving region 11 around the periphery, especially at equal distances from each other. For example, the spring elements 12 each comprise two coil springs 13, which are attached to the inner side 11′ of the receiving region 11. The end of the spring element 12 facing the first or the second layer 1 or 2 is preferably adapted to a radius of curvature which is dictated by the disk-shaped first and second layers 1 and 2. Furthermore, it is provided that a bottom region 11″ of the receiving region 11 has contours in order to improve an intermeshing of the layers being plated, which may also comprise more than two layers of sheet metal materials. Using suitable means not represented here, one or both layers may be heated prior to the plating if needed.

FIGS. 2a to d show schematically consecutive snapshots of the method for producing a shaped part according to a second sample embodiment of the present invention. For example, a die 10 is used for this, as illustrated in FIG. 1. For the plating, it is provided that the disk-shaped first layer 1 and the second layer 2 are arranged one on top of the other inside the receiving region 11 of the die 10. The first and the second layer 1 and 2 have the same diameter here. In particular, the first and the second layer 1 and 2 are placed congruently on top of each other. It is conceivable that the upper second layer 2 terminates flush with an upper edge of the receiving region 11. After the first and second layer 1 and 2 are placed in the receiving region 11, wherein one or both layers may be heated if necessary by suitable means not represented here, the simultaneous forming and plating begins in that two discus-shaped pressing bodies 20 press against the upper, here the second, layer 2, and are moved along a direction running substantially parallel to a principal plane of extension of the layers or a direction running parallel to the bottom region 1″ of the receiving region 11. In particular, this movement is repeated for as long as it takes to produce the desired shape of the shaped part being fabricated. In the present case, the fabricated shaped part comprises a hub.

FIGS. 3a to e show schematically consecutive snapshots of a method for producing a shaped part according to a third sample embodiment of the present invention. It is provided here that the first layer 1 and the second layer 2 are placed one on top of the other on a round blank 31, especially on an end piece of a round blank 31. Preferably, the round blank 31 tapers in the direction of the end piece on which the first layer 1 and the second layer 2 are lying. In particular, it is provided that the diameter of the first layer 1 or the second layer 2 is larger than a maximum diameter of the round blank 31. In this way, the first and second layer 1 and 2 placed on the round blank 31 stick out with respect to a side surface of the round blank 31. For the fixation, a hold-down 32 is provided, the hold-down 32 in a fixation position acting on the second layer 2 and thus holding together the first layer 1 and the second layer 2. By means of the hold-down 32, the first and the second layer 1 and 2 are preferably fixed in common. By suitable means not represented here, one or both layers may be heated if needed. Furthermore, it is provided that a flow turning process is performed by means of two, in particular discus-shaped, pressing bodies 20, by which a plating on the one hand and the forming on the other hand is achieved. In this case, the pressing bodies 20 are moved along a path substantially parallel to an axis of the round blank or along a path dictated by an outer side of the round blank, with the round blank being entirely rotationally symmetrical to the axis. Thanks to the flow turning, in particular, the first and the second layer 1 and 2 after the forming lie jointly against an outer side of the round blank 32 and thus the fabricated shaped part shown in FIG. 3e is provided.

LIST OF REFERENCE NUMBERS

1 First layer

2 Second layer

10 Die

11 Receiving region

11′ Bottom region

11″ Inner side

12 Spring elements

13 Coil spring

20 Pressing body

31 Round blank

32 Hold-down

Claims

1.-12. (canceled)

13. A method for producing a shaped part, the method comprising:

providing a first layer comprising a first sheet metal material and a second layer comprising a second sheet metal material;

forming a preliminary composite that includes the first layer and the second layer;

plating the preliminary composite; and

forming the preliminary composite to obtain the shaped part by way of flow turning, compression, or deep drawing,

wherein plating the preliminary composite is performed before or during the forming of the preliminary composite to obtain the shaped part.

14. The method of claim 13 comprising heating at least one of the first layer or the second layer for the plating.

15. The method of claim 13 wherein the preliminary composite is formed such that the shaped part is rotationally symmetrical to an axis of symmetry at least in some regions.

16. The method of claim 15 wherein the shaped part is formed by compressing the preliminary composite with a pressing body, wherein the pressing body is moved parallel or perpendicular to the axis of symmetry during the compression.

17. The method of claim 13 wherein the first sheet metal material is different than the second sheet metal material.

18. The method of claim 17 wherein the first sheet metal material and the second sheet metal material are comprised of an iron material.

19. The method of claim 17 wherein the first sheet metal material and the second sheet metal material are comprised of a nonferrous material.

20. The method of claim 13 comprising securing the first layer and the second layer for the plating.

21. The method of claim 13 comprising positioning the preliminary composite in a die.

22. The method of claim 21 comprising clamping the preliminary composite in the die by way of a spring element.

23. The method of claim 13 comprising positioning the preliminary composite in an at least partially-contoured receiving region of a die for the plating.

24. The method of claim 13 comprising positioning the preliminary composite on a shape-determining tool body for the plating and the forming.

25. The method of claim 24 wherein the shape-determining tool body is a round blank.

26. A shaped part fabricated by a method comprising:

providing a first layer comprising a first sheet metal material and a second layer comprising a second sheet metal material, wherein the first sheet metal material comprises an iron material with a carbon fraction of more than 0.1% by weight;

forming a preliminary composite that includes the first layer and the second layer;

plating the preliminary composite; and

forming the preliminary composite to obtain the shaped part by way of flow turning, compression, or deep drawing,

wherein plating the preliminary composite is performed before or during the forming of the preliminary composite to obtain the shaped part.

27. The shaped part of claim 26 wherein the carbon fraction in the iron material of the first sheet metal material is more than 0.25% by weight.

28. The shaped part of claim 26 wherein the carbon fraction in the iron material of the first sheet metal material is more than 0.5% by weight.

29. The shaped part of claim 26 configured as a joint head.