A hot-stamped article according to the present invention has a plating layer being attached to a single surface in an amount of 10 g/m.sup.2 or more and 90 g/m.sup.2 or less and having a Ni content of 10 mass % or more and 25 mass % or less with a remainder including Zn and impurities on a surface of a base steel sheet having a predetermined chemical composition, in a surface layer region, a metallographic structure includes 80.0% or more of martensite and 8.0% or more of residual austenite in terms of area percentage, and the concentration of Ni in the surface layer region is 8 mass % or more.

Provided is an alloy-plated steel material that can be used in home appliances, automobiles, and construction materials and the like and, more particularly, to an alloy-plated steel material having excellent corrosion resistance and high surface quality.

Provided is an alloy-plated steel material that can be used in home appliances, automobiles, and construction materials and the like and, more particularly, to an alloy-plated steel material having excellent corrosion resistance and high surface quality.

Provided is a manufacturing method of a surface-treated Zn—Ni alloy electroplated steel sheet, the method comprising the steps of: preparing a Zn—Ni alloy electroplated steel sheet including a steel sheet and a Zn—Ni alloy-plated layer with an Ni content of 5-20 wt % (S1); preparing an alkaline electrolyte solution in which 4-250 g/L of potassium hydroxide (KOH) or sodium hydroxide (NaOH) or both combined are added in distilled water (S2); and inside the alkaline electrolyte solution, placing the Zn—Ni alloy electroplated steel sheet as an anode and installing another metal sheet as a cathode, and applying 2-10 V of an alternating or direct current to conductor electrochemical etching such that a 3-point average value of the arithmetic average roughness (Ra) of the surface of the Zn—Ni alloy electroplated steel sheet reaches 200-400 nm, thereby producing a surface-treated electroplated steel sheet (S3).

Provided is a manufacturing method of a surface-treated Zn—Ni alloy electroplated steel sheet, the method comprising the steps of: preparing a Zn—Ni alloy electroplated steel sheet including a steel sheet and a Zn—Ni alloy-plated layer with an Ni content of 5-20 wt % (S1); preparing an alkaline electrolyte solution in which 4-250 g/L of potassium hydroxide (KOH) or sodium hydroxide (NaOH) or both combined are added in distilled water (S2); and inside the alkaline electrolyte solution, placing the Zn—Ni alloy electroplated steel sheet as an anode and installing another metal sheet as a cathode, and applying 2-10 V of an alternating or direct current to conductor electrochemical etching such that a 3-point average value of the arithmetic average roughness (Ra) of the surface of the Zn—Ni alloy electroplated steel sheet reaches 200-400 nm, thereby producing a surface-treated electroplated steel sheet (S3).

A hot-stamped article according to the present invention has a plating layer being attached in an amount of 10 g/m.sup.2 or more and 90 g/m.sup.2 or less and having a Ni content of 10 mass % or more and 25 mass % or less with a remainder including Zn and an impurity on a surface of a base steel sheet having a predetermined chemical composition, a surface layer region includes 90.0 % or more of martensite in terms of area percentage, and a concentration of Ni in a prior austenite grain boundary in the surface layer region is 5.5 mass % or more.

A hot-stamped article according to the present invention has a plating layer being attached in an amount of 10 g/m.sup.2 or more and 90 g/m.sup.2 or less and having a Ni content of 10 mass % or more and 25 mass % or less with a remainder including Zn and an impurity on a surface of a base steel sheet having a predetermined chemical composition, a surface layer region includes 90.0 % or more of martensite in terms of area percentage, and a concentration of Ni in a prior austenite grain boundary in the surface layer region is 5.5 mass % or more.

A steel sheet for hot stamping according to the present invention has a plating layer being attached in an amount of 10 g/m.sup.2 or more and 90 g/m.sup.2 or less and having a Ni content of 10 mass % or more and 25 mass % or less with a remainder including Zn and impurities on a surface of a base steel sheet having a predetermined chemical composition, in a surface layer region, 15.0% or more of the crystal grains of one or two kinds of unauto-tempered martensite and lower bainite are included in terms of area percentage, and the average dislocation density is 4×10.sup.15 m/m.sup.3.

A steel sheet for hot stamping according to the present invention has a plating layer being attached in an amount of 10 g/m.sup.2 or more and 90 g/m.sup.2 or less and having a Ni content of 10 mass % or more and 25 mass % or less with a remainder including Zn and impurities on a surface of a base steel sheet having a predetermined chemical composition, in a surface layer region, 15.0% or more of the crystal grains of one or two kinds of unauto-tempered martensite and lower bainite are included in terms of area percentage, and the average dislocation density is 4×10.sup.15 m/m.sup.3.

The present invention relates to a plated steel sheet for hot stamping comprising a steel sheet and a Zn—Ni plating layer formed on at least one surface of the steel sheet, wherein the Zn—Ni plating layer has an Ni concentration of 8 mass % or more, a plating deposition amount of 10 g/m.sup.2 or more and 90 g/m.sup.2 or less per surface, and an average grain size of 50 nm or more, and a difference between a diffraction peak of the Zn—Ni plating layer after heat treating the plated steel sheet for hot stamping at 200° C. for 1 hour, and a diffraction peak of the Zn—Ni plating layer before heat treating it, is 0.3° or less.