A pre-coated steel sheet wherein at least a region at the periphery (7) of at least one (6a,6b) of the opposite faces (6a,6b) of said pre-coated sheet (1,1′) is coated with an additional coating (8) selected for increasing the vapor pressure between the pre-coating (2) and said additional coating (8) during a laser welding method up to a critical pressure at which the pre-coating (2) is ejected away from the weld (14). Preferably, the vaporization temperature of the additional coating (8) is greater than the vaporization temperature of the pre-coating (2) and the additional coating includes gammagene elements like carbon and/or nickel. A steel part obtained by laser welding, preferably butt laser welding, of at least a first and second pre-coated steel sheet (1,1′) as above indicated is also provided.

A joining method includes: an overlapping step of overlapping a front surface of a first metal member with a back surface of a second metal member; and a welding step of welding the first metal member with the second metal member by hybrid welding, using a hybrid welding machine including a leading laser welding unit and a trailing arc welding unit. In the welding step, laser welding, by irradiating with a laser beam, and arc welding are performed from a front surface of the second metal member, along a preset travel route which is set on an overlapped part formed by the first metal member and the second metal member overlapped with each other, to the overlapped part, and the laser beam is oscillated to cross the preset travel route.

In a method for manufacturing an energy storage device by applying welding to a container of the energy storage device, the method includes: arranging a jig on which wall surfaces are formed between two parts to be welded to which welding is applied; and welding the two parts to be welded while supplying a shield gas to the two parts to be welded from two different directions corresponding to the two parts to be welded.

A method and associated device for joining a battery cell tab to a plurality of foils associated with a plurality of electrodes of a battery cell are described. This includes arranging the plurality of foils in a stack, and joining, via a first joining device, the plurality of foils, wherein the first joining device defines a joining region. A portion of the battery cell tab is arranged on the plurality of foils, and joined, via a second joining device, to the plurality of foils. The second joining device generates a weld joint that is encompassed within the joining region defined by the first joining device. In doing so, weld quality and strength of internal welds in a battery cell may be improved by reducing the occurrence of porosities and cracks in the foil/tab weld joints.

A method for laser welding two coated workpieces includes positioning an upper workpiece and a lower workpiece on top of each other and passing a first laser beam over the upper and lower workpieces from a side of the upper workpiece so as to at least partially evaporate the respective coating of each of the workpieces on their facing sides along a depletion trace. A second laser beam is passed over the workpieces from the side of the upper workpiece so as to melt a material of the two workpieces within the depletion trace, and thereby weld the workpieces to one another. In the first laser passing, the first laser beam melts the material of the upper workpiece, so that a web of non-melted material of the upper workpiece remaining between the melted material of the upper workpiece and the facing side of the upper workpiece.

A weld inspection apparatus that detects a weld defect in a welded portion of metal plates and includes a liquid application head disposed over one side surface of the metal plates and capable of moving in a welding direction of the metal plates, and an air jet head disposed over another side surface of the metal plates and capable of moving in the welding direction of the metal plates. The liquid application head includes a liquid application nozzle that projects toward the one side surface of the metal plates and applies liquid for sealing the welded portion. The air jet head includes an air jet nozzle that projects toward the another side surface of the metal plates and discharges air toward the welded portion to which the liquid has been applied.

The disclosure relates to methods and systems for joining at least two workpieces, including forming a weld joint by moving a machining beam, e.g., a laser beam, and the at least two workpieces relative to one another along a feed direction, wherein the movement of the machining beam and the two workpieces relative to one another is superimposed with a periodic movement in a movement path, e.g., a two-dimensional movement path, which extends in a transverse direction perpendicularly to the feed direction and, e.g., additionally in the feed direction. The movement path has, between two reversal points in the transverse direction, at least one stop point at which a speed component of the periodic movement in the transverse direction is zero. The invention also relates to computer program products and systems for carrying out the methods.

The disclosure relates to methods and systems for joining at least two workpieces, including forming a weld joint by moving a machining beam, e.g., a laser beam, and the at least two workpieces relative to one another along a feed direction, wherein the movement of the machining beam and the two workpieces relative to one another is superimposed with a periodic movement in a movement path, e.g., a two-dimensional movement path, which extends in a transverse direction perpendicularly to the feed direction and, e.g., additionally in the feed direction. The movement path has, between two reversal points in the transverse direction, at least one stop point at which a speed component of the periodic movement in the transverse direction is zero. The invention also relates to computer program products and systems for carrying out the methods.

A system for welding a first component to a second component. The system includes a first laser head configured to emit a first laser beam and be movably disposable on a first side of the first component. The system further includes a second laser head configured to emit a second laser beam and be movably disposable on an opposing second side of the first component. The system further includes a controller configured to independently control a first power of the first laser beam and a second power of the second laser beam. The controller is also configured to independently and simultaneously control movement of the first laser head and movement of the second laser head relative to the first component.

A welding method includes: emitting a laser beam to a workpiece including a metal; and welding a portion of the workpiece to which the laser beam is emitted by melting. The laser beam includes a main power region and at least one auxiliary power region, power in the main power region is equal to or higher than power in each of the at least one auxiliary power region, and a power ratio of the power in the main power region and a total of the power in the at least one auxiliary power region is within a range of 144:1 to 1:1.