A welded steel part with a very high mechanical strength is provided. The welded steel part is obtained by heating followed by hot forming, then cooling of at least one welded blank obtained by butt welding of at least one first and one second sheet. The at least one first and second sheets including, at least in part, a steel substrate and a pre-coating which includes an intermetallic alloy layer in contact with the steel substrate, topped by a metal alloy layer of aluminum or aluminum-based alloy. A method for the fabrication of a welded steel part and the fabrication of structural or safety parts for automotive vehicles are also provided.

A cutting blade (100) adapted to be carried by a tool holder (20) provided in a robotic work tool (10), the cutting blade (100) comprising a blade body (110) and a cutting edge (120, 121) extending along at least a portion of the periphery (111) of the blade body (110), and a slit (113) arranged to receive a pin (30) for attaching the cutting blade (100) to said tool holder (20), wherein the cutting blade (100) is movable such that the pin (30) may be displaced within the slit (113). The hardness of the cutting blade (100) decreases in direction from the cutting edge (120, 121) towards the center (125) of the blade body (110) such that the hardness of the cutting edge (120, 121) is higher than the hardness of at least a center portion (126) of the blade body (110). The present disclosure also relates to a method for manufacturing a cutting blade.

Provided is a galvanized steel sheet having excellent spot weldability; and a method for producing same. The galvanized steel sheet includes a base steel sheet and a zinc-based plating layer formed on the base steel sheet, wherein the surface layer of the base steel sheet may have a decarburization rate of at least 30% as represented by equation 1. [Equation 1]: Decarburization rate (%) of surface layer=(1−average carbon concentration in surface layer/bulk carbon concentration)*100, where the surface layer refers to a region extending to a depth of 35 μm from the surface of the base steel sheet.

Systems and methods of quenching a metal substrate include cooling a top surface and a bottom surface of the metal substrate until a strip temperature is cooled to an intermediate temperature. Cooling of the top surface of the metal substrate is discontinued when the strip temperature reaches the intermediate temperature, and cooling of the bottom surface of the metal substrate continues until the metal substrate reaches a target temperature, where the target temperature is less than the intermediate temperature.

A method for processing a steel plate capable of removing residual strain at a trim edge thereof without causing overheating in areas of the steel plate other than the trim edge. A method of processing a steel plate includes punching a steel plate and disposing heating electrodes in such a way that a trim edge punched in the punching is positioned between electrode surfaces facing each other and then heating a part of the steel plate including the trim edge.

The present invention generally relates to the modification of a deep-drawing sheet blank (P) for electric resistance heating. Generally, the modified sheet blank comprises slits (Z) being made in the edges of the blank (P) transversely to the electric current flow and oriented towards the perimeter of the forming zone (T). The distances between the ends of the slits (Z) and the forming zone (T) perimeter may be equal. The ends of the slits (Z) oriented towards the forming zone perimeter (T) may also be rounded.

A method of friction welding a first component to a second component, the method having the steps of: rotating the first component relative to the second component about a rotation axis; and bringing the first component into contact with the second component; wherein, while the first component and the second component are in contact, a first average force is applied during a first stage of the friction welding process and a second average force is applied during a second stage of the friction welding process; and the second average force is different from the first average force.

A localized annealing process and a part having localized areas with increased ductility produced by the process. The part is formed of hard material, tempered, and/or otherwise hardened such that it meets minimum hardness and ductility requirements. The part further includes localized areas that have increased ductility for workability, which could include various types of deformation. The localized annealing process includes providing a part with low levels of ductility and then annealing localized areas of the part for increased ductility that will need to be machined or attached to another formed part. The annealing process includes placing an electrode on either side of the localized area and generating electricity through the localized area. The material in the localized area is then heated from the electricity to form a more ductile physical structure.

A method for hot forming a semifinished product in sheet form for a motor vehicle component. The method includes heating the semifinished product to be formed in a heating process and forming the heated semifinished product in a shaping forming process. During the heating process the semifinished product undergoes an input of heat from at least one heat source. During the heating of the semifinished product, a shielding device is arranged between the heat source and the semifinished product, such that the semifinished product is thermally shielded at least in certain portions in such a way that a first semifinished-product portion is heated differently than a second semifinished-product portion.

An electrical steel sheet includes a main surface and an end surface. The electrical steel sheet includes a base material part and an end surface nitrided layer that is provided on the end surface in a manner adjacent to the base material part and that contains nitrogen. The end surface nitrided layer has a surface hardness of 430 HV or more and 1250 HV or less. The end surface contains nitrogen in an amount higher than a nitrogen concentration at the main surface.