The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 03, 2021
Filed:
Jan. 18, 2016
GM Global Technology Operations Llc, Detroit, MI (US);
GM GLOBAL TECHNOLOGY OPERATIONS LLC, Detroit, MI (US);
Abstract
A method of laser spot welding a workpiece stack-up that includes at least two overlapping steel workpieces, at least one of which includes a surface coating, is disclosed. The method includes directing a laser beam at the top surface of the workpiece stack-up to create a molten steel weld pool that penetrates into the stack-up. The molten steel weld pool is then grown to penetrate further into the stack-up by increasing an irradiance of the laser beam while reducing the projected sectional area of the laser beam at a plane of the top surface of the workpiece stack-up. Increasing the irradiance of the laser beam may be accomplished by moving a focal point of the laser beam closer to the top surface or by reducing an angle of incidence of the laser beam so as to reduce the eccentricity of the projected sectional area of the laser beam.