Method for the manufacture of a coated steel sheet including the following step of A) the provision of a pre-coated steel sheet coating with a first coating including iron and nickel, B) the thermal treatment of such pre-coated steel sheet at a temperature between 600 and 1000° C., and C) the coating of the steel sheet obtained in step B) with a second coating based on zinc.

The present disclosure relates to an aluminum-based plated steel that is provided for vehicles by hot forming, an aluminum-based alloy plated steel manufactured using the same, and method of manufacturing thereof.

This joint component is a joint component including a first steel member, a second steel member, and a spot-welded portion that joins the first steel member and the second steel member, in which the first steel member includes a steel sheet substrate having a predetermined chemical composition and a coating that is formed on a surface of the steel sheet substrate, contains Al and Fe, and has a thickness of 25 μm or more, in a cross section in a thickness direction of the first steel member and the second steel member including the spot-welded portion, a filled metal containing Al and Fe is present in a gap between the first steel member and the second steel member in a periphery of the spot-welded portion, in the cross section, the filled metal has a cross-sectional area of 3.0×10.sup.4 μm.sup.2 or more, and has a filling ratio of 80% or more in the gap in a range of 100 μm from an end portion of a corona bond formed in the periphery of the spot-welded portion, and includes a first region and a second region.

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.

The present invention relates to a method of hot dip coating of flat steel products, comprising a step of stripping the coated steel strip by means of at least one nozzle that emits a stripping gas having a temperature T.sub.3 at an angle α in the direction of the coated steel strip, wherein the angle α, the distance h between the surface of the melt bath and the lower edge of the nozzle in mm, the temperature of the stripping gas in ° C. and the differential between the temperature T.sub.2 of the melt bath and the temperature T.sub.1 of the steel strip are in a particular relationship to one another, and to a correspondingly produced hot dip-coated flat steel product.

Provided is a galvanized steel sheet having excellent plating adhesion, having a plated layer with improved friction characteristics by means of a predetermined level of Fe elution, and having excellent corrosion resistance; and a manufacturing method therefor.

The present invention has as its object the provision of a coated steel member and coated steel sheet excellent in hydrogen embrittlement resistance in a corrosive environment and methods for manufacturing the same. The coated steel member of the present invention is provided on its surface with an Al—Fe-based coating containing Cu and one or more of Mo, Ni, Mn, and Cr in a total by mass % of 0.12% or more by heating, cooling, and manufacturing a coated steel sheet having a layer containing Cu on its surface under predetermined conditions.

A hot stamping component and a manufacturing method thereof include: (a) preparing a blank including 0.27 to 0.33 wt % of carbon (C), more than 0 and 0.40 wt % or less of silicon (Si), 1.10 to 1.60 wt % of manganese (Mn), more than 0 and 0.030 wt % or less of phosphorus (P), more than 0 and 0.015 wt % or less of sulfur (S), 0.10 to 0.60 wt % of chromium (Cr), more than 0 and 0.1 wt % or less of titanium (Ti), and 0.0008 to 0.0050 wt % of boron (B); (b) heat-treating the blank; and (c) molding the heat-treated blank and cooling the molded blank. The component and method may stably provide high strength by minimizing hydrogen charging in a hot stamping manufacturing process and preventing hydrogen delayed fracture due to the hydrogen charging.

A coated steel substrate has a steel substrate having a surface. A coating layer is atop the surface. The coating layer includes: aluminum activated by indium; and a ceramic binder. The coating also may comprise of multiple layers with different properties to facilitate the galvanic protection capability.

Provided is an Al-plated hot stamped steel material comprising a steel base material, an Al-plating layer formed on at least one surface of the steel base material, and a chemical conversion coating formed on the Al-plating layer and containing zinc phosphate-based crystals and Ce-based compounds deposited on the surfaces of the zinc phosphate-based crystals, wherein an amount of deposition of the zinc phosphate-based crystals in the chemical conversion coating is, converted to metal Zn, 0.3 to 4.0 g/m.sup.2 and an area ratio of the Ce-based compounds in the chemical conversion coating is 0.5 to 25%.