Provided is a hot-dip galvanized steel sheet to be used for home appliances, vehicles, and the like, and having excellent surface appearance and low-temperature bonding brittleness. The hot-dip galvanized steel sheet includes: a base steel sheet; and a hot-dip galvanized layer formed on the base steel sheet. A surface of the base steel sheet has a centerline average roughness (Ra) of 0.3 or more, a roughness skewness (Rsk) of −1 or less, and a roughness kurtosis (Rku) of 6 or more.

Provided is a steel sheet for a hot press formed member having excellent resistance to hydrogen delayed fracture, and a method for manufacturing the same. A steel sheet for a hot press formed member comprises: a base steel sheet; an aluminum alloy plating layer on a surface of the base steel sheet; and an oxide layer which is formed on a surface of the plating layer and has a thickness of 0.05 μm or more.

The present invention relates to a steel sheet for a hot press formed member having excellent coating adhesion, and a method for manufacturing the same. A steel sheet for hot press forming according to one aspect of the present invention is an aluminum alloy plated steel sheet, wherein an average Fe content in a plating layer may be 40 wt % or more, and a concentration gradient of a section having a Fe content of 45 wt % to 80 wt % in the plating layer may 7 wt %/μm or less of a concentration gradient at a section having an Fe content of 45% to 80% in the plating layer in a thickness direction from a surface of the plating layer according to a result of GDS analysis.

A coated steel product including a base steel, and a coating layer containing a Zn—Al—Mg alloy layer disposed on a surface of the base steel, in which the coating layer has a predetermined chemical composition, the coated steel product including dendrite-shaped MgZn.sub.2 phase having a surface roughness Sa of 50 nm or less on a surface of the Zn—Al—Mg alloy layer, an area ratio of the dendrite-shaped MgZn.sub.2 phase having a surface roughness Sa of 50 nm or less being from 30% to 80% within a region of an observable field of view of 5 mm.sup.2, and among the dendrite-shaped MgZn.sub.2 phase having a surface roughness Sa of 50 nm or less, a number of dendrite-shaped MgZn.sub.2 phase having an area of 0.1 mm.sup.2 or more being from 5 to 100 within a region of an observable field of view of 25 mm.sup.2.

A method for fabricating a substrate provided with a plurality of layers, includes: providing a steel substrate with an oxide layer including metal oxides on the steel substrate; providing a metal coating layer directly on the oxide layer, the metal coating layer including: at least 8% by weight nickel; at least 10% by weight chromium; and a remainder being iron and impurities from a fabrication process; and providing an anti-corrosion coating layer directly on the metal coating layer.

A steel sheet with a metallic coating is provided. A composition of the metallic coating includes from 2.0 to 24.0% by weight of zinc, from 7.1 to 12.0% by weight of silicon, optionally from 1.1 to 8.0% by weight of magnesium, and optionally additional elements chosen from Pb, Ni, Zr, or Hf. The content by weight of each additional element is less than 0.3%. A balance of the composition is aluminum, unavoidable impurities and residual elements. A ratio Al/Zn is from 4.0 to 6.0.

Provided are an austenite-based molten aluminum-plated steel sheet comprising: a steel plate which contains, by weight %, 0.3 to 0.9% of C, 12 to 25% of Mn, 0.5 to 2.5% of Si, 0.3 to 3.0% of Al, 0.01 to 0.5% of Ti, 0.05 to 0.5% of V, 0.01-0.5% of Mo, 0.01-0.2% of Sn, 0.001-0.1% of Co, and 0.001-0.1% of W, the remainder being Fe and unavoidable impurities; and a molten aluminum-based plated layer formed on a surface of the steel plate, and a method for producing the same.

A plating steel sheet for hot press forming includes: a base steel sheet; an Al—Zn-based plating layer formed on at least one surface of the base steel sheet; and an Fe—Al-based surface alloy layer formed between the base steel sheet and the Al—Zn-based plating layer, wherein the Al—Zn-based plating layer can include 10-30 wt % of Zn, 1 wt % or less of Fe, and the balance of Al and impurities.

A hot stamped steel includes a base material that is formed of steel, a plated layer that is formed on a surface of the base material, and a phosphate coating that is formed on a surface of the plated layer; chemical composition of the plated layer contains 20.00 to 45.00 mass % of Al, 10.00 to 45.00 mass % of Fe, 4.50 to 15.00 mass % of Mg, 0.10 to 3.00 mass % of Si, 0.05 to 3.00 mass % of Ca, 0 to 0.50 mass % of Sb, 0 to 0.50 mass % of Pb, 0 to 1.00 mass % of Cu, 0 to 1.00 mass % of Sn, 0 to 1.00 mass % of Ti, 0 to 0.50 mass % of Sr, 0 to 1.00 mass % of Cr, 0 to 1.00 mass % of Ni, and 0 to 1.00 mass % of Mn with a remainder of Zn and impurities; the phosphate coating consists of zinc phosphate crystals containing 5.0 to 50.0 mass % of Mg and 0.5 to 5.0 mass % of Ca; and the adhesion amount of the phosphate coating per one surface is in a range of 0.1 to 10.0 g/m.sup.2.

Provided is a steel sheet for a hot press formed member having excellent resistance to hydrogen delayed fracture, and a method for manufacturing the same. A steel sheet for a hot press formed member comprises: a base steel sheet; an aluminum alloy plating layer on a surface of the base steel sheet; and an oxide layer which is formed on a surface of the plating layer and has a thickness of 0.05 μm or more.