Abstract: A method of laser welding together two or more overlapping metal workpieces (12, 14, or 12, 150, 14) included in a welding region (16) of a workpiece stack-up (10) involves advancing a beam spot (44) of a laser beam (24) relative to a top surface (20) of the workpiece stack-up along a first weld path (72) in a first direction (74) to form an elongated melt puddle (76) and, then, advancing the beam spot (44) of the laser beam (24) along a second weld path (78) in a second direction (80) that is opposite of the first direction while the elongated melt puddle is still in a molten state. The first weld path and the second weld path overlap so that the beam spot of the laser beam is conveyed through the elongated melt puddle when the beam spot is advanced along the second weld path.

Abstract: A method of laser welding together two or more overlapping light metal workpieces (12, 14, or 12, 150, 14) involves advancing a laser beam (24) relative to the top surface (20) of the workpiece stack-up (10) multiple times along a closed-curve weld path (72). The conductive heat transfer associated with such advancement of the laser beam (24) grows and develops a larger melt puddle (76) that penetrates into the workpiece stack-up (10) and intersects each faying interface (34 or 160, 162) established within the stack-up (10). Upon halting transmission of the laser beam (24) or otherwise removing the laser beam (24) from the closed-curved weld path (72), the melt puddle (76) solidifies into a laser weld joint (66) comprised of resolidified composite workpiece material (78).

Abstract: A laser welder and associated method for joining battery cell foils to a battery tab is described. The joining method includes arranging the plurality of battery cell foils in a stack, wherein the first edges of the battery cell foils are disposed in parallel. The battery cell foils arranged in the stack are positioned such that the first edges of the battery cell foils underlap with the battery tab. A compressive load may be applied to the plurality of battery cell foils and the battery tab. The laser welder executes welding operation to form a weld joint that mechanically and electrically joins the battery cell foils and the battery tab. The welding operation includes the laser welder applying a laser beam to the second surface of the battery tab. The welding operation is executed near first edges of the battery cell foils.

Abstract: A method for joining together metal workpieces (12, 14, 150) includes advancing a beam spot (44) of a laser beam (24) relative to the top surface (20) of the workpiece stack-up (10) along a primary beam travel pattern (78) to create a molten metal portion (70) within the workpiece stack-up and, thereafter, reducing a power density of the laser beam and moving the beam spot of the laser beam relative to an upper surface (82) of the molten metal portion along a secondary beam travel pattern (84) to introduce heat into the molten metal portion such that the molten metal portion is prevented from fully solidifying and at least an upper region (86) of the molten metal portion that includes the upper surface is maintained in a molten state. The laser beam is then removed from the molten metal portion to allow the molten metal portion to solidify into a laser weld joint (66). The laser weld joint have a smooth top surface.

Abstract: A device and associated method for joining, via a laser welder, a first workpiece to a second workpiece is described. This includes arranging the first and second workpieces in a stack, including overlapping a portion of the first workpiece with a portion of the second workpiece. The laser welder generates a first laser beam and coincidentally controls the laser welder to traverse a desired weld path that is disposed on the top surface of the first workpiece. The laser devices generates a second laser beam and coincidentally controls the laser welder to traverse the desired weld path. Generating, via the laser welder, the first laser beam includes operating the laser welder at a pulsed operation and at a first power level. Generating, via the laser welder, the second laser beam includes operating the laser welder at a continuous operation and at a second power level.

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.

Abstract: A multicolored aglet connected to a shoelace has a unit slice, a pattern layer, and a white background layer. The unit slice is formed into two aglet bodies that are respectively sheathed on two ends of the shoelace, and has a mounting portion. The mounting portion of the unit slice is stuck to an outer side of the unit slice. The pattern layer is printed on and covers the inner side of the unit slice excluding the mounting portion, and is located between the unit slice and the shoelace. The white background layer is printed on the pattern layer and is located between the pattern layer and the shoelace. A method for producing the multicolored aglet is also provided.

Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping steel workpieces, at least one of which includes a surface coating of a zinc-based material. The method includes forming at least one preliminary weld deposit (74) in the workpiece stack-up (10) and, thereafter, forming a principal laser weld joint. The formation of the principal laser spot weld joint involves advancing a principal welding laser beam (90) relative to a plane of the top surface (20) of the workpiece stack-up (10) along a beam travel pattern (104) that lies within an annular weld area (92). The beam travel pattern (104) of the principal welding laser beam (90) surrounds a center area (98) on the plane of the top surface (20) that spans the at least one preliminary weld deposit (74) formed in the workpiece stack-up (10).

Abstract: A method for laser welding a plurality of battery foils to a battery tab that does not include ultrasonic welding and includes clamping the plurality of battery foils and the battery tab together. Each of the plurality of battery foils has a thickness that is between 0.004 millimeters and 0.03 millimeters. The battery tab has a thickness that is between 0.1 millimeters and 0.5 millimeters. The method further includes laser welding the plurality of battery foils to the battery tab.

Abstract: A method of laser spot welding a workpiece stack-up (10) that includes at least two overlapping steel workpieces (12, 14, 150) is disclosed. The method includes directing a plurality of laser beams (24, 24?, 24?) at the top surface (20) of the workpiece stack-up to create a molten steel weld pool (92) that penetrates into the stack-up. The molten steel weld pool is then grown to penetrate further into the stack-up by increasing an overall combined irradiance of the laser beams while reducing the total projected sectional area (88) of the laser beams at a plane of the top surface of the workpiece stack-up. Increasing the overall combined irradiance of the laser beams may be accomplished by moving the focal points (66, 66?, 66?) of the laser beams closer to the top surface or by reducing the mean angle of incidence (86) of the laser beams so as to reduce the eccentricity of the individual projected sectional areas of the laser beams.

Abstract: A method of laser welding a workpiece stack-up (10, 10?) that includes at least two overlapping metal workpieces (12, 150, 14) comprises advancing a beam spot (44) of a laser beam (24) relative to a top surface (20) of the workpiece stack-up (10, 10?) and along a beam travel pattern (66) to form a laser weld joint (64) that fusion welds the metal workpieces (12, 150, 14) together. While the beam spot (44) is being advanced between a first point (76) and a second point (78) of one or more weld paths (74) of the beam travel pattern (66), the position of a focal point (52) of the laser beam (24) is oscillated relative to the top surface (20) of the workpiece N stack-up (10, 10?) along a dimension (68) oriented transverse to the top surface (20).

Abstract: Semiconductor device and fabrication method are provided.

Abstract: A multilayer steel includes a core formed of transformation-induced plasticity (TRIP) steel. A decarburized layer is exterior to the core on at least one side thereof. The decarburized layer has reduced carbon content relative to the core. A zinc-based layer is exterior to the decarburized layer. The decarburized layer may have a composition of at least 80 percent ferrite, such that LME is reduced or mitigated. In some configurations, the decarburized layer is between 10-50 microns thick. A method of creating a coated advanced high-strength steel component is also provided. An apparatus for forming a coated advanced high-strength steel is also provided. The core of the multilayer steel may have a carbon weight-percent of less than or equal to 0.4. The decarburized layer of the multilayer steel may have a carbon weight-percent of less than or equal to 50 percent of the carbon weight-percent of the core.

Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping aluminum workpieces comprises advancing a laser beam (24) relative to a plane of a top surface (20) of the workpiece stack-up (10) and along a beam travel pattern (74) that lies within an annular weld area (82) defined by an inner diameter boundary (86) and an outer diameter boundary (84) on the plane of the top surface (20). The beam travel pattern (74) of the laser beam (24) surrounds a center area encircled by the annular weld area (82) on the plane of the top surface (20) so as to force entrained porosity inwards into a region of the weld joint (72) beneath the center area on the plane of the top surface (20) of the workpiece stack-up (10).

Abstract: A method of welding a workpiece stack-up assembly that includes dissimilar metal workpieces involves melting a portion of a top metal workpiece that overlies an underlying metal workpiece and covers at least one intruding hollow feature defined in the underlying metal workpiece. The molten material of the top metal workpiece flows into the at least one intruding feature defined in the underlying metal workpiece and, upon solidification therein, establishes a weld joint that metallurgically secures the top and underlying metal workpieces together. The top metal workpiece comprises a base metal substrate and the underlying metal workpiece comprises a base metal substrate. The base metal substrate of the top metal workpiece is different than the base metal substrate of the underlying metal workpiece and has a melting point that is less than a melting point of the base metal substrate of the underlying metal workpiece.

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).

Abstract: A method of laser welding together two or more overlapping metal workpieces (12, 14 or 12, 504, 14) that define a welding region (16) in which at least a portion of an accessible top surface (20, 120, 220, 520) of a workpiece stack-up (10, 110, 210, 510) is curved or angled includes advancing a laser beam (24) along a beam travel pattern (74) that at least partially lies on the portion of the top surface that is curved or angled while maintaining a constant focal distance (64) of the laser beam during such advancing travel. The beam travel pattern may be projected onto a curved portion (20?, 220?) of the top surface, an angled portion (120?) of the top surface, or two or more portions (20?, 20?, 120?, 120?, 220?, 220?, 220??) of the top surface that lack planarity.

Abstract: A method of laser welding a workpiece stack-up (10) that includes at least two overlapping metal workpieces (12, 14) comprises advancing a laser beam (24) relative to a plane of a top surface (20) of the workpiece stack-up (10) from a start point (84) to an end point (86) along a beam travel pattern (78) at a high laser beam travel speed of greater than 8 meters per minute. The two or more overlapping metal workpieces (12, 14) may be steel workpieces or they may be aluminum workpieces, and at least one of the metal workpieces (12, 14) includes a surface coating (40). Advancing the laser beam (24) along the beam travel pattern (78) forms a weld joint (76), which includes resolidified composite workpiece material derived from each of the metal workpieces (12, 14) penetrated by a molten weld pool (80), that fusion welds the metal workpieces (12, 14) together. The relatively high laser beam travel speed contributes to improve strength properties of the weld joint (76).

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.

Abstract: A multilayer steel includes a core formed of transformation-induced plasticity (TRIP) steel. A decarburized layer is exterior to the core on at least one side thereof. The decarburized layer has reduced carbon content relative to the core. A zinc-based layer is exterior to the decarburized layer. The decarburized layer may have a composition of at least 80 percent ferrite, such that LME is reduced or mitigated. In some configurations, the decarburized layer is between 10-50 microns thick. A method of creating a coated advanced high-strength steel component is also provided. An apparatus for forming a coated advanced high-strength steel is also provided. The core of the multilayer steel may have a carbon weight-percent of less than or equal to 0.4. The decarburized layer of the multilayer steel may have a carbon weight-percent of less than or equal to 50 percent of the carbon weight-percent of the core.