Method of hot press forming an article from zinc or zinc alloy coated steel, wherein the steel is a product obtained by: casting the molten steel into slabs; reheating the slabs; hot rolling the steel into a strip, preferably with an FRT above Ar3; coiling the hot rolled steel strip; pickling the hot rolled steel strip; continuous annealing the strip; hot dip coating the steel strip with the zinc or zinc alloy whilst: using a dipping time of 3 seconds or more; maintaining in the hot dip bath a bath temperature of 420° C. to 500° C.; wherein the zinc bath contains essentially zinc, at least 0.1% Al, and optionally up to 5% Al and optionally up to 4% Mg, the rest of the bath including further elements all individually less than 0.3%, and unavoidable impurities; hot press forming the article.

This hot-dip Zn—Al—Mg-based plated steel includes: a steel; and a plating layer formed on a surface of the steel, in which the plating layer contains, as an average composition, Mg: 1 to 10 mass %, Al: 4 to 22 mass %, and a remainder consisting of Zn and impurities, the plating layer includes an (Al—Zn mixed structure) in an area ratio of 10% to 70% in a cross section of the plating layer in a matrix of an (Al/Zn/MgZn.sub.2 ternary eutectic structure), the (Al—Zn mixed structure) includes a first region that has a Zn concentration in a range of 75 mass % or more and less than 85 mass % and a second region that is present inside the first region and has a Zn concentration in a range of 67 mass % or more and less than 75 mass %, and an area ratio of the second region in the (Al—Zn mixed structure) in the cross section of the plating layer is more than 0% and 40% or less.

This hot-dip Zn—Al—Mg-based plated steel includes: a steel; and a plating layer formed on a surface of the steel, in which the plating layer contains, as an average composition, Mg: 1 to 10 mass %, Al: 4 to 22 mass %, and a remainder consisting of Zn and impurities, the plating layer includes an (Al—Zn mixed structure) in an area ratio of 10% to 70% in a cross section of the plating layer in a matrix of an (Al/Zn/MgZn.sub.2 ternary eutectic structure), the (Al—Zn mixed structure) includes a first region that has a Zn concentration in a range of 75 mass % or more and less than 85 mass % and a second region that is present inside the first region and has a Zn concentration in a range of 67 mass % or more and less than 75 mass %, and an area ratio of the second region in the (Al—Zn mixed structure) in the cross section of the plating layer is more than 0% and 40% or less.

Provided are a plated steel sheet and a method for manufacturing same, the plated steel sheet comprising: a base steel sheet; a Zn—Mg—Al based steel sheet plating layer provided on at least one surface of the base steel sheet; and an Fe—Al based inhibition layer provided between the base steel sheet and the Zn—Mg—Al based plating layer, wherein the plating layer comprises, in wt %: 4% or more of Mg; 2.1 times or more of Mg content and 14.2% or less of Al; 0.2% or less (including 0%) of Si; 0.1% or less (including 0%) of Sn; the remainder Zn; and unavoidable impurities.

Provided are a plated steel sheet and a method for manufacturing same, the plated steel sheet comprising: a base steel sheet; a Zn—Mg—Al based steel sheet plating layer provided on at least one surface of the base steel sheet; and an Fe—Al based inhibition layer provided between the base steel sheet and the Zn—Mg—Al based plating layer, wherein the plating layer comprises, in wt %: 4% or more of Mg; 2.1 times or more of Mg content and 14.2% or less of Al; 0.2% or less (including 0%) of Si; 0.1% or less (including 0%) of Sn; the remainder Zn; and unavoidable impurities.

The invention relates to a sheet metal having a deterministic surface structure, the surface structure being impressed into the sheet metal, the surface structure having at least one peak region and at least one valley region, the peak region and the valley region being joined by a flank region. The invention further relates to a method for producing a formed and coated sheet-metal component.

A method for production of a flat steel product including at least the following steps, completed in a continuous process: providing a flat steel product, wherein a protective metal layer of Zn, a Zn—Al alloy, a Zn—Mg alloy or a Zn—Mg—Al alloy is applied to at least one side by hot dip coating; at least partly removing a native oxide layer present on the surface of the protective metal layer by wetting this surface with an acidic solution of sulfuric acid, sulfurous acid, hydrochloric acid, phosphoric acid, phosphonic acid, nitric acid, formic acid, oxalic acid, acetic acid, citric acid, malic acid, tartaric acid, nitrous acid or hydrofluoric acid; activating the surface of the protective metal layer by applying an aqueous activation solution to the surface of the protective metal layer; and phosphating the activated surface of the protective metal layer by applying an aqueous phosphating solution to the activated surface.

A method for production of a flat steel product including at least the following steps, completed in a continuous process: providing a flat steel product, wherein a protective metal layer of Zn, a Zn—Al alloy, a Zn—Mg alloy or a Zn—Mg—Al alloy is applied to at least one side by hot dip coating; at least partly removing a native oxide layer present on the surface of the protective metal layer by wetting this surface with an acidic solution of sulfuric acid, sulfurous acid, hydrochloric acid, phosphoric acid, phosphonic acid, nitric acid, formic acid, oxalic acid, acetic acid, citric acid, malic acid, tartaric acid, nitrous acid or hydrofluoric acid; activating the surface of the protective metal layer by applying an aqueous activation solution to the surface of the protective metal layer; and phosphating the activated surface of the protective metal layer by applying an aqueous phosphating solution to the activated surface.

The present disclosure relates to a zinc plated steel sheet having excellent fatigue strength of electrical resistance spot welds and a method for manufacturing the same. According to an aspect of the present disclosure, a zinc plated steel sheet includes a base steel sheet and a zinc-based plating layer formed on a surface of the base steel sheet, wherein a concentration profile of one or two of oxygen, and silicon and manganese measured in a depth direction from the surface of the base steel sheet has a maximum point in the depth direction from the surface, and an absolute value of a difference between a depth at which the maximum point of the concentration profile of oxygen is formed and a depth at which the maximum point of the concentration profile of one of silicon and manganese is formed is 0.5 μm or less.

The present disclosure relates to a zinc plated steel sheet having excellent fatigue strength of electrical resistance spot welds and a method for manufacturing the same. According to an aspect of the present disclosure, a zinc plated steel sheet includes a base steel sheet and a zinc-based plating layer formed on a surface of the base steel sheet, wherein a concentration profile of one or two of oxygen, and silicon and manganese measured in a depth direction from the surface of the base steel sheet has a maximum point in the depth direction from the surface, and an absolute value of a difference between a depth at which the maximum point of the concentration profile of oxygen is formed and a depth at which the maximum point of the concentration profile of one of silicon and manganese is formed is 0.5 μm or less.