Method for welding components

Patent metadata

Field	Value
Publication number	US-11839930-B2
Application number	US-201816210087-A
Country	US
Kind code	B2
Filing date	Dec 5, 2018
Priority date	Jul 1, 2016
Publication date	Dec 12, 2023
Grant date	Dec 12, 2023

Abstract

A method for welding components includes the following steps: providing a first component and a second component; bringing together the two components; welding the two components by use of a laser beam, wherein a plurality of welding impulses are generated through the repeated activation and deactivation of the laser beam, with each welding pulse being interrupted by welding-free rest intervals in which the laser beam is deactivated, wherein a local welding area is generated by each welding pulse, in which material of the two components is melted and fused in a locally limited manner, wherein individual welding areas of those generated by the welding pulses overlap.

First claim

What is claimed is:

1. A method for welding components, the method comprising the steps of:
providing a first component and a second component;
placing the two components on each other; and
welding the two components together by a laser beam, wherein the welding comprises the steps of:
switching on the laser beam for a first pulse duration, during which the laser beam is stationary, so as to generate a first welding pulse at a first position that melts and fuses the two components and thereby produces a first local welding area at the first position;
switching off the laser beam for a welding-free pause interval, during which the first local welding area solidifies and the laser beam is moved relative to the two components from the first position to a second position; and
after the welding-free pause interval, switching on the laser beam for a second pulse duration, during which the laser beam is stationary, so as to generate a second welding pulse that melts and fuses the two components at the second position and thereby produces a second local welding area at the second position, the second position overlapping the first position,

wherein the welding-free pause interval is of different duration than at least one of: the first pulse duration and the second pulse duration, and
wherein the first component is a ball made from steel, aluminum or thermoplastic, which is welded onto the second component that is a body component of a vehicle body to be produced.

2. The method as claimed in claim 1 , wherein the first local welding area and the second local welding area overlap within a series of local welding areas to form a cohesive, fluid-tight weld seam.

3. The method as claimed in claim 1 , wherein the second welding pulse directly follows the welding-free pause interval, which directly follows the first welding pulse.

4. The method as claimed in claim 1 , wherein the first pulse duration and the second pulse duration are each respectively within: 0.1 ms to 100 ms, 0.1 ms to 50 ms, 0.1 ms to 20 ms, 1 ms to 20 ms, or 1 ms to 10 ms.

5. The method as claimed in claim 1 , wherein the first pulse duration is of identical duration to the second pulse duration.

6. The method as claimed in claim 1 , wherein the first pulse duration is of different duration than the second pulse duration.

7. The method as claimed in claim 1 , wherein the laser beam has a power density between 10 4 watt/cm 2 and 10 10 watt/cm 2 .

8. The method as claimed in claim 7 , wherein the first welding pulse has an identical power density to the second welding pulse.

9. The method as claimed in claim 7 , wherein the first welding pulse has a different power density than the second welding pulse.

10. The method as claimed in claim 7 , wherein the laser beam has a beam diameter or a beam width between 40 μm and 4 mm.

11. The method as claimed in claim 10 , wherein the first welding pulse has an identical beam diameter or beam width to the second welding pulse.

12. The method as claimed in claim 1 , wherein the laser beam has a circular beam cross section.

13. The method as claimed in claim 1 , wherein the first welding pulse has a different beam diameter or beam width than the second welding pulse.

14. The method as claimed in claim 1 , wherein the welding is carried out with a repetition rate within a range of between 200 Hz and 10 kHz.

15. The method as claimed in claim 1 , further comprising:
producing via the welding, a weld seam extending around the ball in a contact region of the ball on the second component.

16. The method as claimed in claim 1 , wherein a power density of the first welding pulse and/or the second welding pulse is changed by:
changing the laser power with the beam cross section being kept constant,
changing the beam cross section with the laser power being kept constant, or
changing the laser power and the beam cross section.

Assignees

• Bayerische Motoren Werke Ag

Inventors

• Hammer Maik
• Van Niekerk Johann
• Grimm Alexander

Classifications

• B23K26/0622 Primary

  by shaping pulses · CPC title

• B23K26/062

  by direct control of the laser beam · CPC title

• B23K26/0626

  Energy control of the laser beam (B23K26/0622 takes precedence) · CPC title

• B23K26/22

  Spot welding · CPC title

• B23K26/242

  Fillet welding, i.e. involving a weld of substantially triangular cross section joining two parts · CPC title