A metal substrate provided with surface textures wherein different texture patterns are provided over predefined surface areas of the metal substrate and wherein the different texture patterns are tailored to predefined surface properties of a product which is to be made out of the metal substrate as well as to a method for applying such surface textures on the metal substrate.

A laser-welded lap joint includes a weld zone formed by joining a plurality of steel sheets one over another together by laser welding. The weld zone has a J shape and includes a main weld zone having a linear weld line shape and a weld terminal end zone having an arcuate or circular weld line shape. The length L.sub.1 of the main weld zone is ⅔ or more and ⅘ or less of the full length L of the weld zone represented by formula (1). The radius R of the weld terminal end zone satisfies formula (2). The angle θ of the weld terminal end zone satisfies formula (3). The total size of a gap between the plurality of steel sheets in a lapped portion is 0% or more and 15% or less of the total thickness of the plurality of steel sheets.

A metal joined body has an iron base body and an aluminum base body that are joined together via a joint layer. The joint layer has a first layer composed of a first intermetallic compound formed on the iron base body side and a second layer composed of a second intermetallic compound formed on the aluminum base body side. The first layer has one or more first protrusions that merge integrally into the iron base body and extend in a pile shape into the first intermetallic compound. The second layer may have one or more second protrusions that are composed of a second intermetallic compound and extend in a columnar shape into the aluminum base body. The first intermetallic compound may contain Al.sub.5Fe.sub.2, and the second intermetallic compound may contain Al.sub.3Fe. The total thickness of the first layer and the second layer is, for example, 2 to 15 μm.

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.

The present invention relates to a method for joining a first blank and a second blank, wherein at least one of the first and second blanks comprises at least a layer of aluminum or an aluminum alloy. In particular, the method comprises placing the first and second blanks for welding; laser welding the first and second blanks following a welding path thus forming a tailor welded blank, wherein the welding path combines a linear movement along a welding direction and oscillating movements substantially transverse to the welding direction and then hot deforming and quenching the tailor welded blank to form a component, wherein the welding is done without using a filler.

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.

A method for producing a shaped sheet of wrapping, including a hollow portion and a perimetral edge that extends along a pre-set profile, is provided. The method includes laying a sheet of wrapping on a treatment surface having a forming cavity. The method includes forming the sheet of wrapping within the forming cavity so as to reproduce the shape of the hollow portion thereon, without subjecting the sheet of wrapping to deformation by stretching. The method includes cutting the formed sheet of wrapping along the pre-set profile for producing the perimetral edge and obtaining the shaped sheet of wrapping. In the method, the cutting step envisages the use of a laser beam according to a particular cutting mode.

A method for butt welding of flat metal blanks in a welding machine, where two metal blanks are placed on a conveyor unit by feed devices and secured by holding means. Two edges of two metal blanks to be welded together are placed together to form a butt joint with the smallest possible gap and then welded together using a welding laser. The gap width is measured and controlled by means of the measured values from the welding process. The gap width is measured by means of the reflected-light method and the true gap width by means of the transmitted light method in such a way that the missing area and the missing volume in the gap can be estimated accurately.

A steel sheet for the manufacture of a press hardened part is provided, having a composition of: 0.15%≤C≤0.22%, 3.5%≤Mn<4.2%, 0.001%≤Si≤1.5%, 0.020%≤Al≤0.9%, 0.001%≤Cr≤1%, 0.001%≤Mo≤0.3%, 0.001%≤Ti≤0.040%, 0.0003%≤B≤0.004%, 0.001%≤Nb≤0.060%, 0.001%≤N≤0.009%, 0.0005%≤S≤0.003%, 0.001%≤P≤0.020%. A microstructure has less than 50% ferrite, 1% to 20% retained austenite, cementite, such that the surface density of cementite particles larger than 60 nm is lower than 10{circumflex over ( )}7/mm.sup.2, and a complement of bainite and/or martensite, the retained austenite having an average Mn content of at least 1.1*Mn %. Press-hardened steel part obtained by hot forming the steel sheet, and manufacturing methods thereof.

There is provided a component joining structure that includes: a resin component; a metal tip that is provided in the resin component by insert molding, and that includes protruding portions that protrude from the resin component; and a metal component that is spot welded to the protruding portions, and that is joined to the resin component by an adhesive agent that is provided in gaps formed, by the protruding portions, between the resin component and the metal component.