Multi-step direct welding of an aluminum-based workpiece to a steel workpiece
US9999938B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 20, 2014 |
| Grant date | Jun 19, 2018 |
| Priority date | — |
| Expiry date | Mar 13, 2037 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB23K2103/20
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A workpiece stack-up that includes at least a steel workpiece and an aluminum-based workpiece can be resistance spot welded by employing a multi-stage spot welding method in which the passage of electrical current is controlled to perform multiple stages of weld joint development. The multiple stages include: (1) a molten weld pool growth stage in which a molten weld pool is initiated and grown within the aluminum-based workpiece; (2) a molten weld pool solidification stage in which the molten weld pool is allowed to cool and solidify into a weld nugget that forms all or part of a weld joint; (3) a weld nugget re-melting stage in which at least a portion of the weld nugget is re-melted; and (4) a re-melted weld nugget solidification stage in which the re-melted portion of the weld nugget is allowed to cool and solidify.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.