公开(公告)号：US20190061053A1

公开(公告)日：2019-02-28

申请号：US15685290

申请日：2017-08-24

Applicant: GM Global Technology Operations LLC

Inventor： David Yang ,  Justin Wolsker ,  Blair Carlson ,  Wu Tao

IPC: B23K26/08 ,  B23K26/244 ,  B23K26/10

Abstract: A method of laser brazing a metal workpiece assembly along a joint seam established between a first metal workpiece and a second metal workpiece involves advancing a laser beam along the joint seam while feeding a filler wire into the laser beam to melt a leading end of the filler wire, which is impinged by the laser beam, to produce and dispense molten filler material within and along the joint seam. The dispensed molten filler material solidifies behind the laser beam into a braze joint. Additionally, as part of the method, a position of a focal point of the laser beam relative to the leading end of the filler wire is repeatedly fluctuated during advancement of the laser beam along at least part of the joint seam.

公开(公告)号：US20190001428A1

公开(公告)日：2019-01-03

申请号：US15638699

申请日：2017-06-30

Applicant: GM Global Technology Operations LLC

Inventor： David Yang ,  Wu Tao ,  Qi Lu ,  Blair E Carlson

IPC: B23K11/11 ,  B23K11/16 ,  B23K11/36 ,  B32B15/01

Abstract: A method of resistance spot welding a workpiece stack-up comprising overlapping first and second steel workpieces is disclosed, wherein at least one of the steel workpieces comprises an advanced high-strength steel substrate. The workpiece stack-up is positioned between a pair of opposed first and second welding electrodes. A cover is disposed between at least one of the first steel workpiece and the first welding electrode or the second steel workpiece and the second welding electrode at an intended weld site. The workpiece stack-up is clamped between the first and second welding electrodes at the weld site such that at least one of the weld faces of the first and second welding electrodes presses against the cover. The first and second steel workpieces are welded together by passing an electrical current between the first and second welding electrodes at the weld site.

公开(公告)号：US20180214983A1

公开(公告)日：2018-08-02

申请号：US15747287

申请日：2015-08-31

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： David S. Yang ,  Wu Tao

IPC: B23K26/244 ,  B23K26/082 ,  B23K26/322

CPC classification number: B23K26/244 ,  B23K26/082 ,  B23K26/322 ,  B23K2101/006 ,  B23K2101/18 ,  B23K2101/34 ,  B23K2103/10

Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping aluminum workpieces (12, 14), at least one of which includes a protective anti-corrosion coating (38), is disclosed. The disclosed method includes advancing the laser beam (56) relative to the top surface (26) of the workpiece stack-up (10) along a travel path (78, 78′, 78″, 78′″) that imposes bidirectional movement of the laser beam (56). In particular, the laser beam (56) moves in a forward direction (80) while also moving back and forth in a lateral direction (82) oriented transverse to the forward direction (80) as it is being advanced relative to the top surface (26). Such bidirectional movement is believed to help disturb the protective anti-corrosion coating (38) in and around the molten aluminum weld pool (74), thus leading to a laser weld joint (68) that contains less weld defects derivable from the protective anti-corrosion coating(s) (38).

公开(公告)号：US20180043472A1

公开(公告)日：2018-02-15

申请号：US15659092

申请日：2017-07-25

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： David Yang ,  Wu Tao ,  Paolo A. Novelletto ,  Yu Pan ,  Justin Wolsker

IPC: B23K26/244 ,  B23K26/08

Abstract: A method of laser welding a workpiece stack-up that includes two or more overlapping metal workpieces is disclosed. The disclosed method includes directing a laser beam at a top surface of the workpiece stack-up to create a molten metal weld pool and, optionally, a keyhole, and further gyrating the laser beam to move a focal point of the laser beam along a helical path having a central helix axis oriented transverse to the top and bottom surfaces of the workpiece stack-up. The gyration of the laser beam may even be practiced to move the focal point of the laser beam along a plurality of helical paths so as to alternately convey the focal point back-and-forth in a first overall axial direction and a second overall axial direction while advancing the laser beam relative to the top surface of the workpiece stack-up along a beam travel pattern.

公开(公告)号：US20180009060A1

公开(公告)日：2018-01-11

申请号：US15206856

申请日：2016-07-11

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： David Yang ,  Wu Tao

IPC: B23K26/06 ,  B23K26/21 ,  B23K26/322 ,  B23K103/10 ,  B23K103/16 ,  B23K103/04 ,  B23K103/08

CPC classification number: B23K26/0626 ,  B23K26/082 ,  B23K26/0884 ,  B23K26/244 ,  B23K26/32 ,  B23K26/322 ,  B23K2101/006 ,  B23K2101/18 ,  B23K2101/34 ,  B23K2103/04 ,  B23K2103/10 ,  B23K2103/15 ,  B23K2103/166 ,  B23K2103/20

Abstract: A method of laser welding a workpiece stack-up that includes at least two overlapping metal workpieces is disclosed. The method includes advancing a beam spot of a laser beam relative to a top surface of the workpiece stack-up and along a beam travel pattern to form a laser weld joint, which is comprised of resolodified composite metal workpiece material, that fusion welds the metal workpieces together. And, while the beam spot is being advanced along the beam travel pattern, between a first point and a second point, which may or may not encompass the entire beam travel pattern, at least one of the following laser beam parameters is repeatedly varied: (1) the power level of the laser beam; (2) the travel speed of the laser beam; or (3) the focal position of the laser beam relative to the top surface of the workpiece stack-up.

公开(公告)号：US11077522B2

公开(公告)日：2021-08-03

申请号：US15779743

申请日：2016-01-18

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： David Yang ,  Wu Tao ,  Li Sun

IPC: B23K26/20 ,  B23K26/32 ,  B23K26/22 ,  B23K26/073 ,  B23K26/322 ,  B23K103/10 ,  B23K103/00 ,  B23K101/34 ,  B23K101/00

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.

公开(公告)号：US10953497B2

公开(公告)日：2021-03-23

申请号：US16085283

申请日：2016-11-23

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： Hui-Ping Wang ,  Yu Pan ,  Blair E. Carlson ,  Joshua L. Solomon ,  William P. Payne ,  David Yang ,  Wu Tao

IPC: B23K26/60 ,  B23K26/26 ,  B23K26/322 ,  B23K26/082 ,  B23K26/244 ,  B23K101/00 ,  B23K101/18 ,  B23K101/34 ,  B23K103/04

Abstract: A method of laser welding a workpiece stack-up (10) of overlapping steel workpieces (12, 14) involves heat-treating a region (64) of the stack-up (10) followed by forming a laser weld joint (66) that is located at least partially within the heat-treated region (64). During heat-treating, one or more pre-welding laser beams (68) are sequentially directed at a top surface (20) of the workpiece stack-up (10) and advanced along a pre-welding beam travel pattern (70) so as to reduce an amount of vaporizable zinc within the stack-up (10). Thereafter, the laser weld joint (66) is formed by directing a welding laser beam (82) at the top surface (20) of the workpiece stack-up (10) and advancing the welding laser beam (82) along a welding beam travel pattern (84) that at least partially overlaps with a coverage area of a pre-welding beam travel pattern (70) or a shared coverage area portion of multiple pre-welding beam travel patterns (70). The method can help reduce an amount of vaporizable zinc within the stack-up (10).

公开(公告)号：US20200316714A1

公开(公告)日：2020-10-08

申请号：US16085901

申请日：2016-04-14

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： David Yang ,  Wu Tao

IPC: B23K26/22 ,  B23K26/322 ,  B23K26/60 ,  B23K26/34 ,  B23K26/082 ,  B23K26/06

Abstract: A method of laser spot welding a workpiece stack-up (10) includes initially forming at least one hole (74) in the workpiece stack-up and, thereafter, forming a laser spot weld joint (86). The formation of the laser spot weld joint involves directing a welding laser beam (24) at the top surface (20) of the workpiece stack-up to create a molten steel weld pool (98) that penetrates into the stack-up, and then advancing the welding laser beam relative to a plane of the top surface of the workpiece stack-up along a beam travel pattern (102) that lies within an annular weld area (90). The beam travel pattern of the welding laser beam surrounds a center area (96) on the plane of the top surface that spans the at least one hole formed in the workpiece stack-up. The workpiece stack-up includes at least two overlapping steel workpieces, at least one of which includes a surface coating of a zinc-based material. This method can minimize porosity within the weld joint.

公开(公告)号：US10675701B2

公开(公告)日：2020-06-09

申请号：US15638699

申请日：2017-06-30

Applicant: GM Global Technology Operations LLC

Inventor： David Yang ,  Wu Tao ,  Qi Lu ,  Blair E Carlson

IPC: B23K11/11 ,  B23K11/16 ,  B23K11/36 ,  B32B15/01

Abstract: A method of resistance spot welding a workpiece stack-up comprising overlapping first and second steel workpieces is disclosed, wherein at least one of the steel workpieces comprises an advanced high-strength steel substrate. The workpiece stack-up is positioned between a pair of opposed first and second welding electrodes. A cover is disposed between at least one of the first steel workpiece and the first welding electrode or the second steel workpiece and the second welding electrode at an intended weld site. The workpiece stack-up is clamped between the first and second welding electrodes at the weld site such that at least one of the weld faces of the first and second welding electrodes presses against the cover. The first and second steel workpieces are welded together by passing an electrical current between the first and second welding electrodes at the weld site.

公开(公告)号：US20200094350A1

公开(公告)日：2020-03-26

申请号：US16484010

申请日：2017-02-09

Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC

Inventor： Yu Pan ,  David Yang ,  Wu Tao ,  Paolo Novelletto

IPC: B23K26/22 ,  B23K26/08 ,  B23K26/082 ,  B23K26/244

Abstract: A method for joining together metal workpiece (12,14 or 12,150,14) includes forming a laser weld joint (66) in a workpiece stack-up (10) that fusion welds two or more overlapping metal workpiece (12,14 or 12,150 or 14) together. The laser weld joint (66) has an initial top surface (76). Once the laser weld joint (66) is formed, the method calls for impinging the laser weld joint (66) with a laser beam (24) and moving the laser beam (24) along the initial joint (66) including the initial top surface (76). The laser beam (24) is eventually removed from the laser weld joint (66) to allow the melted upper portion (78) of the joint (66) to resolidify and provide the laser weld joint (66) with a modified top surface (84) that is smoother than the initial top surface (76). By providing the laser weld joint with a smoother modified top surface, residual stress concentration points are removed and the laser weld joint is less liable to damage seal strips.