Provided is a solution composition for steel sheet surface treatment, comprising 30 wt % to 60 wt % of a trivalent chromium compound containing chromium phosphate (A) and chromium nitrate (B); 0.2 wt % to 0.4 wt % of a rust-inhibiting and corrosion-resisting agent; 0.1 wt % to 0.3 wt % of a molybdenum-based compound; 5 wt % to 10 wt % of a water-soluble cationic urethane resin; 0.5 wt % to 2.0 wt % of a silane coupling agent; and 27.3 wt % to 64.2 wt % of water, a zinc-based plated steel sheet surface-treated with the same, and a manufacturing method therefor, the zinc-based plated steel sheet surface-treated with the solution composition for steel sheet surface treatment containing trivalent chromium may have an excellent effect on corrosion resistance, blackening resistance, fingerprint resistance, oil resistance, and alkali resistance.

There is provided a hot-stamped body including: a steel base metal; and a metallic layer formed on a surface of the steel base metal, wherein the metallic layer includes: an interface layer that contains, in mass %, Al: 30.0 to 36.0%, has a thickness of 100 nm to 5 μm, and is located in an interface between the metallic layer and the steel base metal; and a principal layer that includes coexisting MgZn.sub.2 phases and insular FeAl.sub.2 phases, is located on the interface layer, and has a thickness of 3 μm to 40 μm.

There is provided a hot-stamped body including: a steel base metal; and a metallic layer formed on a surface of the steel base metal, wherein the metallic layer includes: an interface layer that contains, in mass %, Al: 30.0 to 36.0%, has a thickness of 100 nm to 5 μm, and is located in an interface between the metallic layer and the steel base metal; and a principal layer that includes coexisting MgZn.sub.2 phases and insular FeAl.sub.2 phases, is located on the interface layer, and has a thickness of 3 μm to 40 μm.

Provided is a hot-dip galvanized steel sheet having excellent low-temperature adhesion and workability, and a manufacturing method therefor, the hot-dip galvanized steel sheet comprising: an inhibition layer formed on a base steel sheet and comprising an Fe—Al-based intermetallic alloy phase; a hot-dip galvanized layer formed on the inhibition layer; and an Al—Mn-based alloy phase discontinuously formed between the inhibition layer and the hot-dip galvanized layer.

Provided is a hot-dip galvanized steel sheet having excellent low-temperature adhesion and workability, and a manufacturing method therefor, the hot-dip galvanized steel sheet comprising: an inhibition layer formed on a base steel sheet and comprising an Fe—Al-based intermetallic alloy phase; a hot-dip galvanized layer formed on the inhibition layer; and an Al—Mn-based alloy phase discontinuously formed between the inhibition layer and the hot-dip galvanized layer.

Provided is a plated steel material which can be used for an automobile, a household appliance, a building material, and the like and, more specifically, to a zinc alloy plated steel material having excellent surface quality and corrosion resistance, and a method for manufacturing the same.

Provided is a plated steel material which can be used for an automobile, a household appliance, a building material, and the like and, more specifically, to a zinc alloy plated steel material having excellent surface quality and corrosion resistance, and a method for manufacturing the same.

A surface-treated metal material includes a metal sheet, a plating layer formed on the metal sheet and containing aluminum, magnesium, and zinc, and a composite coating formed on a surface of the plating layer, the composite coating including an organic silicon compound, one or two of a zirconium compound and a titanium compound, a phosphoric acid compound, a fluorine compound, and a vanadium compound, wherein, when a surface of the composite coating is analyzed at a spot size of φ30 μm using micro-fluorescent X-rays, a maximum value of V/Zn, which is a mass ratio of a V content to a Zn content, is 0.010 to 0.100.

A plated steel sheet includes: a steel sheet; and a plating layer that is formed on at least a part of a surface of the steel sheet, in which a chemical composition of the plating layer includes, by mass %, Al: more than 5.00% and 35.00% or less, Mg: 3.00% to 15.00%, Si: 0% to 2.00%, Ca: 0% to 2.00%, and a remainder of Zn and impurities, in which in a cross section of the plating layer in a thickness direction, the area ratio of a lamellar structure in which an (Al—Zn) phase and a MgZn.sub.2 phase are arranged in layers is 10% to 90%, a lamellar spacing of the lamellar structure is 2.5 μm or less, and the area ratio of an (Al—Zn) dendrite is 35% or less.

The present invention enables quick cooling of steam-treated objects and thus reduces the manufacturing time of steam-treated products such as black coated steel sheets. The present invention provides a method for manufacturing steam-treated products, which involves a steam treatment step that introduces steam into a closed container (10) containing a treatment object (1) and brings the treatment object (1) into contact with the steam, and a treated object cooling step that cools the object (1) treated with steam in the steam treatment step, wherein said treated object cooling step introduces coolant gas into said closed container (10), brings said treated object (1) into contact with the coolant gas, and discharges the introduced coolant gas from said closed container (10).