Abstract
A method is provided for producing a steel component assembly, wherein a steel component having a predetermined breaking point is provided and the predetermined breaking point of the steel component is punched through by way of a press-fit element in order to form an opening. Subsequently, the press-fit element is pressed into the opening of the steel component, and, at least in overlap with the press-fit element, a component is adhesively bonded to the steel component by an adhesive applied over an area. A friction-drilling hole is melted through the press-fit element, the steel component and the component by way of a friction-drilling element.
Claims
1. A method for producing a steel component assembly, comprising: providing a steel component with a predetermined breaking point; punching the predetermined breaking point of the steel component by way of a press-fit element so as to form an opening; pressing the press-fit element into the opening of the steel component; adhesively bonding a component that overlaps at least with the press-fit element to the steel component by use of an adhesive that is applied in a planar manner; and melting a friction-drilling hole through the press-fit element, the steel component, and the component, by way of a friction-drilling element.
2. The method according to claim 1, wherein the steel component is provided with the predetermined breaking point during hardening.
3. The method according to claim 1, wherein the friction-drilling hole is established by the friction-drilling element during a curing procedure of the adhesive.
4. The method according to claim 1, wherein an aluminum frame as the component is adhesively bonded to the steel component so as to overlap the press-fit element.
5. The method according to claim 1, wherein the predetermined breaking point is generated by incorporating a perforation in the steel component.
6. The method according to claim 1, wherein the predetermined breaking point is generated by way of a local material narrowing of the steel component by a forming element.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 shows a schematic sectional view of a steel component having a predetermined breaking point.
(2) FIG. 2 shows a schematic sectional view of the steel component according to FIG. 1 having the predetermined breaking point, as well as a press-fit element which is disposed so as to be spaced apart from the steel component.
(3) FIG. 3 shows a schematic sectional view of the steel component according to FIG. 1 having the predetermined breaking point and the press-fit element which bears on the steel component.
(4) FIG. 4 shows a schematic sectional view of the steel component having the press-fit element which is disposed in an opening of the steel component.
(5) FIG. 5 shows a schematic sectional view of the steel component having the press-fit element which is pressed into the opening of the steel component.
(6) FIG. 6 shows a schematic sectional view of the steel component having the pressed-in press-fit element according to FIG. 5, and a component being adhesively bonded thereto by way of an adhesive.
(7) FIG. 7 shows a schematic sectional view of the steel component having the press-fit element disposed in the opening, the component being adhesively bonded thereto by the adhesive, and a friction-drilling screw, wherein a friction-drilling hole has been melted through the press-fit element by way of the friction-drilling screw.
(8) FIG. 8 shows a schematic sectional view of the steel component having the press-fit element disposed in the opening and the component adhesively bonded by the adhesive, as well as having the friction-drilling screw by which a friction-drilling hole has been melted through the press-fit element, the steel component, and the component.
DETAILED DESCRIPTION OF THE DRAWINGS
(9) A method for producing a steel component assembly 1 is illustrated in a schematic sectional view when viewing FIGS. 1 to 8 in combination. A steel component 2 having a predetermined breaking point 3 is shown in a schematic sectional view in FIG. 1. The predetermined breaking point 3 is generated by way of a local material narrowing 4 in a defined region of the steel component 2. The steel component 2 presently is a press-hardened steel component for a motor vehicle. The steel component 2 presently is provided with the predetermined breaking point 3 during hardening. Alternatively, the predetermined breaking point 3 can be generated by way of a perforation of the steel component 2.
(10) It is illustrated in a schematic sectional view in FIG. 2 how a press-fit element 5 is disposed in the region of the predetermined breaking point 3 so as to be spaced apart from the steel component 2. It can be seen in a schematic sectional view of the steel component 2 illustrated in FIG. 3 how the press-fit element 5 is disposed on the predetermined breaking point 3 on the steel component 2. The predetermined breaking point 3 of the steel component 2, by impingement with a force by means of the press-fit element 5, is punched so as to form an opening 6. As is illustrated in FIG. 4, the press-fit element 5, after the punching of the predetermined breaking point 3 of the steel component 2, is disposed in the opening 6 of the steel component 2. By further impinging the press-fit element 5 with a force, the press-fit element 5 is pressed into the opening 6 of the steel component 2, as is illustrated in a schematic sectional view in FIG. 5, such that the press-fit element 5 completely fills the opening 6.
(11) After pressing the press-fit element 5 into the opening 6 of the steel component 2, a component 7 that overlaps at least with the press-fit element 5 is adhesively bonded to the steel component 2 by way of an adhesive 8 that is applied in a planar manner. The component 7 presently is an aluminum base frame of the motor vehicle. The adhesive 8 can be applied in a planar manner to the component 7 and/or to the steel component 2. During a curing procedure of the adhesive 8, a friction-drilling hole 9 is melted through the press-fit element 5, the steel component 2, and the component 7, by means of a friction-drilling element, in particular a friction-drilling screw 10. The melting is performed by virtue of friction and an increase in temperature resulting therefrom in the region about the friction-drilling screw 10.
(12) As is illustrated in FIG. 7, the friction-drilling screw 10 for generating the friction-drilling hole 9 is placed on the press-fit element 5 and is first moved through the latter. The friction-drilling hole 9 is subsequently melted through the adhesive 8 and the component 7. As can be seen in a schematic sectional view in FIG. 8, the press-fit element 5 melts as a result of a generation of heat when generating the friction-drilling hole 9 and on account thereof changes its shape. It is illustrated in FIG. 8 how the press-fit element 5 melts into a layer formed by the adhesive 8 and thus shields or seals, respectively, the adhesive 8 in relation to the friction-drilling screw 10. After the friction-drilling hole 9 has been generated, the friction-drilling screw 10 can continue to be disposed in the friction-drilling hole 9, or can be removed from the friction-drilling hole 9 after the adhesive 8 and the press-fit element 5 that has melted as a result of the heat generation have solidified.
(13) The method described in the context of FIGS. 1 to 8 herein is based on the concept that it is currently not possible to join press-hardened steel components by means of the friction-drilling screw 10 and an adhesive layer lying therebetween without the adhesive 8, on account of the heat generation close to the friction-drilling screw 10, contaminating the region about the friction-drilling hole 9 on the press-hardened steel component 2, or on the component 7, respectively. A remedy is achieved by way of the press-fit element 5 in that the latter seals said region. The press-fit element 5 should have a strength that is relatively minor in comparison to the press-hardened steel component 2, this leading to an incorporation of the press-fit element 5 into the steel component 2 is currently not possible without a through bore. It is problematic that the press-fit element 5 is softer than the steel component 2 but is intended to penetrate the latter. Since a penetration, or punching, respectively, of the steel component 2 by means of the press-fit element 5 that is softer in comparison to the steel component 2 is currently not possible without a through bore, an additional process step which is associated with additional costs is required.
(14) In order for said additional process step to be avoided, the steel component assembly 1 is produced by the method as described in the context of FIGS. 1 to 8. In a manner similar to a closure of a beverage can or a SIM card, the predetermined breaking point 3 in the form of the opening 6 to be generated later is to be incorporated during the production process of the steel component 2. Said predetermined breaking point 3 as a trench-shaped depression in the steel component 2 is created on account of a contour on a tool half which in a production process of the press-hardened steel component 2 is pushed into a material of the steel component 2. This pushing requires only little force since the steel component 2 on account of being heated in the production process is present so as to be almost doughy. No chip or waste which would have to be discharged is created herein. The additional process step which would be, for example, laser cutting or punching prior to incorporating the press-fit element 5, can thus advantageously be saved.
LIST OF REFERENCE SIGNS
(15) 1 Steel component assembly 2 Steel component 3 Predetermined breaking point 4 Material narrowing 5 Press-fit element 6 Opening 7 Component 8 Adhesive 9 Friction-drilling hole 10 Friction-drilling screw
(16) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.
