This disclosure relates to weldability of steel alloys that provide weld joints which retain hardness values in a heat affected zone adjacent to a fusion zone and which also have improved resistance to liquid metal embrittlement due to the presence of zinc coatings.

This disclosure relates to weldability of steel alloys that provide weld joints which retain hardness values in a heat affected zone adjacent to a fusion zone and which also have improved resistance to liquid metal embrittlement due to the presence of zinc coatings.

Laser welding methods include focusing laser radiation onto a first metal sheet disposed on a metal part, optionally with one or more intervening metal sheets therebetween. The laser radiation is steered to trace at least one spiral path to spot-weld together the metal parts. The laser radiation includes a center beam and an annular beam to maintain a stable keyhole. One method is tailored to weld aluminum parts, e.g., with high gas content and/or dissimilar compositions, and the laser radiation traces first an outward spiral path and then an inward spiral path. The center beam is pulsed during one segment of the inward spiral path. Another method is tailored to weld steel or copper parts having a coating at an interface therebetween, and the laser radiation traces an inward spiral path. The interface may be a zero-gap interface, or a non-zero gap may exist.

A multi-tubular beam for a vehicle, such as a vehicle structure or a bumper reinforcement, includes an elongated beam formed with a metal sheet. The metal sheet has a central section and outer sections extending along a length of the metal sheet. The outer sections are disposed in opposing directions from the outer edges of the central section to provide adjacent first and second tubular portions. The central section forms a common center wall between the adjacent first and second tubular portions. A first edge portion of the metal sheet is disposed along and in parallel alignment with the center wall. The first edge portion is attached to the center wall at a first weld joint to form the first tubular portion. The first weld joint includes a weld material that extends through a thickness of the center wall and into a thickness of the first edge portion.

A hot formed joined blank includes a first metal blank having an ultimate tensile strength of ≥about 1300 MPa to ≤about 2000 MPa and defining a first surface, a second metal blank having an ultimate tensile strength of ≥about 400 MPa to ≤about 1200 MPa and defining a second coated surface having a coating disposed thereon. The coating includes aluminum and silicon or in alternative variations, zinc. A third surface of the second metal blank is joined to the first surface of the first metal blank to form the hot formed joined blank. A weld nugget is disposed along a boundary between the first and second metal blanks that is configured to join the first and second metal blanks, where the weld nugget optionally includes less than or equal to about 1.5 weight percent aluminum or a microstructure comprising austenite and delta-ferrite.

An exemplary embodiment of the present invention discloses an aluminum-based blank including: a first plated steel plate; a second plated steel plate connected to the first plated steel plate; and a joint connecting the first plated steel plate and the second plated steel plate at a boundary between the first plated steel plate and the second plated steel plate.

An exemplary embodiment of the present invention discloses an aluminum-based blank including: a first plated steel plate; a second plated steel plate connected to the first plated steel plate; and a joint connecting the first plated steel plate and the second plated steel plate at a boundary between the first plated steel plate and the second plated steel plate.

A finned tube having a tube main body, on the outside of which, in particular separate or integral, fins are arranged, preferably circumferentially, wherein the fins and/or the tube main body are of a multi-layer material.

A welded steel part obtained by welding a first sheet with a second sheet, at least one with a coating of aluminum alloy. The welding uses a welding wire which, after melting and cooling, constitutes a weld bead connecting the first sheet to the second sheet and being part of said welded steel part. The respective peripheral edge of the first and second sheets are in a joggled edge type configuration in which the peripheral edge of the first sheet is arranged above, and on or near the upper face of an end portion of the peripheral edge of the second sheet which is extended by an inclined junction portion, at least one part of the upper face of the inclined junction portion delimits at least laterally with the edge of the peripheral edge of the first sheet a groove receiving the weld bead, the inclined joining portion extending by a welding portion in longitudinal continuity with the peripheral edge of the first sheet.

A welded steel part obtained by welding a first sheet with a second sheet, at least one with a coating of aluminum alloy. The welding uses a welding wire which, after melting and cooling, constitutes a weld bead connecting the first sheet to the second sheet and being part of said welded steel part. The respective peripheral edge of the first and second sheets are in a joggled edge type configuration in which the peripheral edge of the first sheet is arranged above, and on or near the upper face of an end portion of the peripheral edge of the second sheet which is extended by an inclined junction portion, at least one part of the upper face of the inclined junction portion delimits at least laterally with the edge of the peripheral edge of the first sheet a groove receiving the weld bead, the inclined joining portion extending by a welding portion in longitudinal continuity with the peripheral edge of the first sheet.