Method for fixing a connecting element on a workpiece and component comprising a workpiece with a connecting element fixed on it
Provided herein is a method for securely fixing a connecting element on a metal workpiece by welding involving the formation of locally confined weld points that permits the friction-increasing, play-free, reversible connection of joined workpieces for applications in assembly and transportation. The connecting element includes a metal foil having hard material particles fixed on the joining surfaces by a metallic binding layer. Similarly, a component having a metal workpiece and the connecting element, which is suitable for the connection of workpieces to be joined in machine, plant, and motor vehicle construction, is also provided.
1. A method for fixing a connecting element on a metal workpiece configured to permit a friction-increasing, play-free, and reversible connection of workpieces to be joined, wherein the connecting element comprises a metal foil having hard material particles on its joining surfaces fixed on the metal foil by means of a metallic binding layer, the method comprising the steps of:
positioning the connecting element on a joining surface of the metal workpiece;
applying a pressing force to the connecting element to minimize a gap between the connecting element and the joining surface such that the connecting element lies flat on the joining surface; and thereafter
forming a number of locally confined weld points to securely fix the connecting element on the metal workpiece, for purposes of assembly and transportation, by welding.
2. The method of claim 1 , wherein the welding is performed by laser welding.
3. The method of claim 2 , wherein an Nd:YAG solid-state laser welding unit is used for the laser welding.
4. The method of claim 2 , wherein pulsed lasers with a wavelength of 900 to 1200 nm are used for the laser welding.
5. The method of claim 1 , wherein the pressing force is 20 to 100 N.
6. The method of claim 1 , wherein the welding is performed by resistance spot welding.
7. The method of claim 1 , wherein the connecting element is fixed on the metal workpiece by an uneven number of weld points.
8. The method of claim 7 , wherein the number of weld points is 3, 5, or 7.
9. The method of claim 1 , wherein the metal foil of the connecting element has a thickness of ≦0.2 mm.
10. The method of claim 9 , wherein the thickness is 0.1-0.2 mm.
11. The method of claim 1 , wherein the metal foil of the connecting element is a spring-elastic steel foil having a tensile strength of 350-1850 N/mm 2 .
12. The method of claim 11 , wherein the spring-elastic steel foil has a tensile strength of 800-1600 N/mm 2 .
13. The method of claim 1 , wherein the hard material particles of the connecting element are selected from the group consisting of: carbides, nitrides, borides, diamond, SiO 2 and Al 2 O 3 .
14. The method of claim 13 , wherein the hard material particles of the connecting element are selected from the group consisting of: diamond, silicon carbide and boron carbide.
15. The method of claim 1 , wherein the hard material particles of the connecting element have a grain size of 6 to 80 μm and an average grain size D 50 in the range of 8 to 35 μm.
16. The method of claim 1 , wherein the metallic binding layer of the connecting element is a galvanotechnically produced layer of chemical nickel.
17. The method of claim 1 , wherein the metallic binding layer of the connecting element has a thickness less than an average grain size of the hard material particles.
18. The method of claim 1 , wherein the metal workpiece on which the connecting element is fixed consists of a cast material, steel, aluminum, an aluminum alloy or a sintered metal.