Described herein is a method for producing a shaped sheet of wrapping, including a hollow portion and a perimetral edge that extends along a pre-set profile, said method comprising the steps of: laying a sheet of wrapping on a treatment surface having a forming cavity; forming said sheet of wrapping within said forming cavity so as to reproduce the shape said hollow portion thereon, without subjecting said sheet of wrapping to deformation by stretching; cutting said formed sheet of wrapping along said pre-set profile for producing said perimetral edge and obtaining said shaped sheet of wrapping.

The method is characterised in that the cutting step envisages the use of a laser beam according to a particular cutting mode.

An automotive framework member 1 includes a first steel sheet 10, a second steel sheet 20, and a first weld metal part 40 joining an interface between the first steel sheet 10 and the second steel sheet 20, in which tensile strength of the first steel sheet 10 is 1.0 GPa or more and 1.6 GPa or less, tensile strength of the second steel sheet 20 is 1.8 GPa or more and 2.5 GPa or less, the first steel sheet 10 includes a groove part 18, the second steel sheet 20 is overlapped with the groove part 18, and a minimum Vickers hardness of a region within 4 mm of a periphery of the first weld metal part 40 of the second steel sheet 20 is 80% or more of a hardness of an outside of the region of the second steel sheet 20.

An automotive framework member 1 includes a first steel sheet 10, a second steel sheet 20, and a first weld metal part 40 joining an interface between the first steel sheet 10 and the second steel sheet 20, in which tensile strength of the first steel sheet 10 is 1.0 GPa or more and 1.6 GPa or less, tensile strength of the second steel sheet 20 is 1.8 GPa or more and 2.5 GPa or less, the first steel sheet 10 includes a groove part 18, the second steel sheet 20 is overlapped with the groove part 18, and a minimum Vickers hardness of a region within 4 mm of a periphery of the first weld metal part 40 of the second steel sheet 20 is 80% or more of a hardness of an outside of the region of the second steel sheet 20.

A method for producing a precoated steel sheet (1) includes providing a precoated steel strip comprising a steel substrate carrying, on at least one of its faces, a precoating. The precoating includes an intermetallic alloy layer and a metallic alloy layer extending atop the intermetallic alloy layer. The metallic alloy layer is a layer of aluminum, a layer of aluminum alloy or a layer of aluminum-based alloy. The method also includes laser cutting the precoated steel strip so as to obtain at least one precoated steel sheet (1). The precoated steel sheet (1) includes at least one cut edge surface (13). The cut edge surface (13) includes a substrate region (14) and a precoating region (15) and the thickness of the precoated steel sheet (1) being comprised between 1 mm and 5 mm. The laser cutting is carried out such that it results directly in a reduced-aluminum zone (20), extending over the entire height (h) of the cut edge surface (13) and over a length smaller than or equal to the length thereof. The surface fraction of aluminum on the substrate region (14) of the reduced-aluminum zone (20) directly results from the laser cutting operation being comprised between 0.3% and 6%.

A method for producing a precoated steel sheet (1) includes providing a precoated steel strip comprising a steel substrate (3) having, on at least one of its main faces, a precoating comprising an intermetallic alloy layer and a metallic alloy layer. The metallic alloy layer is a layer of aluminum, a layer of aluminum alloy or a layer of aluminum-based alloy. The method also includes laser cutting said precoated steel strip so as to obtain at least one precoated steel sheet (1) comprising a cut edge surface (13) resulting from the cutting operation. The cut edge surface (13) includes a substrate region (14) and a precoating region (15) and the thickness of the precoated steel sheet (1) is comprised between 0.8 mm and 5 mm. The laser cutting is carried out such that it results directly in a corrosion-improved zone (19) of the cut edge surface (13). The surface fraction of aluminum on the substrate region (14) of the corrosion-improved zone (19) is greater than or equal to 9% and the surface fraction of aluminum on the bottom half of the substrate region (14) of the corrosion-improved zone (19) is greater than or equal to 0.5%.

A method for forming a large-diameter special-shaped cross section thin-wall tubular part. A tailor welded barrel blank is adopted as an original blank for forming of the large-diameter special-shaped cross section thin-wall tubular part. After a desired shape is formed, the original weld joint is removed and butt joint tailor welding is performed on the tubular part again. Since the tailor weld joint of the original barrel blank is removed from the final part, there is no need to consider the consistency or coordination of the microstructure of the weld joint and the base metal during the forming process and the subsequent thermal treatment process.

An electric resistance spot welding device, comprising a pair of electrodes located on the same welding surface of an assembly to be welded. The assembly to be welded is provided with an axis of symmetry (6); the pair of electrodes are symmetrically disposed on two sides of the axis of symmetry; one end of each electrode has a special-shaped contact surface (20); the special-shaped contact surfaces are respectively offset in directions away from the axis of symmetry relative to the electrode axis, wherein the special-shaped contact surfaces are used for offsetting a current density centerline (21) formed by the electrodes in a direction away from the axis of symmetry relative to the electrode axis (11), and/or used for deflecting the tendency of the current density of each electrode away from a welding face within the assembly to be welded. The device can achieve a symmetrical and uniform shape of distal and proximal ends of a nugget with respect to the axis of symmetry, such that both the shape and stress state of the nugget can meet requirements for mechanical properties under load, thus improving the welding quality. The present application also relates to an electric resistance spot welding method.

A method for producing a part includes providing a first and a second precoated sheet (1,2), butt welding the first and second precoated sheets (1) to obtain a blank (15), and heating the blank (15) to a heat treatment temperature at least 10 C. lower than the full austenitization temperature of the weld joint (22) and at least 15 C. higher than a minimum temperature T

[00001]$T_{\min }\left(.Math..Math.C.\right)=\mathrm{AC}.Math..Math.3.Math.\left(\mathrm{WJ}\right)-\frac{{}_{\mathrm{IC}}^{\max }}{100}.Math.\left(\mathrm{Ac}.Math..Math.3.Math.\left(\mathrm{WJ}\right)-673-40\mathrm{Al}\right).$ where Ac3(WJ) is the full austenitization temperature of the weld joint (22)

[00002]$ IC max = ( 1 - ( 1 + ) .Math. ( max ( 1 .Math. ; .Math. ) .Math. Ts 2 - 350 ) ( 1 - ) .Math. ( .Math. .Math. Ts 2 + Ts 1 ) + ( 1 + ) .Mat Method for producing a welded metal blank and thus obtained welded metal blank 20210046577 · 2021-02-18 · Wolfram Ehling, Niko VAN DER BORGHT A method for producing a welded metal blank (16) includes cutting a first initial metal sheet (1) and a second initial metal sheet (3) from a first and second metal strip (4); joining the first and second initial metal sheets (1,3) by welding so as to obtain an initial welded metal blank (9), the initial welded metal blank (9) comprising a weld joint (10) joining the first and the second initial metal sheets (1,3); and cutting said initial welded metal blank (9) by a process involving metal melting so as to obtain at least one final welded metal blank (16) comprising a first metal blank portion (17) and a second metal blank portion (18) joined by a weld joint portion (19) consisting of a portion of the weld joint (10) obtained during the joining step. Friction Stir Welding Apparatus and Friction Stir Welding Method 20210086293 · 2021-03-25 · Tomio ODAKURA, Hiroki ABE, Akihiro SATOU, Kohei FUNAHARA, Koichi ISHIGURO, Shun SHINOHARA, Yukihiro SUGIMOTO, Katsuya NISHIGUCHI, Koujirou TANAKA, Yasuhiro MORITA Provided are a friction stir welding apparatus and a friction stir welding method that achieve highly accurate and highly reliable joining while minimizing an effect of bending of a pressing force receiving portion (carrying table) as a result of a press by a joining tool unit. The friction stir welding apparatus joins joining target members by friction stir welding. The friction stir welding apparatus is characterized by including: an apparatus main body; a control device that controls an operation of the friction stir welding apparatus; a C-shaped frame connected to the apparatus main body via a first vertical movement drive mechanism unit; a holder unit connected to one end of the C-shaped frame via a second vertical movement drive mechanism unit; and a joining tool held by the holder unit. The C-shaped frame includes a held portion connected to the apparatus main body via the first vertical movement drive mechanism unit, a holder unit holding portion connected to the holder unit via the second vertical movement drive mechanism unit, and a pressing force receiving portion connected to the other end of the C-shaped frame and receiving a pressing force from the joining tool. The control device includes a first joining mode that performs friction stir welding based on a joining command signal that determines a joining condition of the joining tool, and a first holding position determining signal that determines a first holding position of the first vertical movement drive mechanism unit, and a second joining mode that performs friction stir welding based on the joining command signal and a second holding position determining signal obtained by correcting the first holding position determining signal such that a depth or a range of a joined portion becomes constant in accordance with a state of the pressing force receiving portion. The first joining mode and the second joining mode are included in one joining pass from insertion of the joining tool into the joining target members to extraction of the joining target members. $