Zn alloy plated steel material having excellent weldability and processed-part corrosion resistance and a method for production of Zn alloy plated steel material are provided. In the Zn alloy plated steel material comprising base steel material and a Zn alloy plating layer, the Zn alloy plating layer includes, by wt %, Al: 0.1-5.0%, Mg: 0.1-5.0%, as well as a remainder of Zn and inevitable impurities. The Zn alloy plated steel material includes a lower interface layer and an upper interface layer between the base steel material and the Zn alloy plating layer, wherein the lower interface layer is formed on the base steel material and has a dense structure, and the upper interface layer is formed on the lower interface layer and has a network-type or island-type structure.

A coated metallic substrate is provided, including, at least; one layer of oxides, such layer being directly topped by an intermediate coating layer comprising Fe, Ni, Cr and Ti wherein the amount of Ti is above or equal to 5 wt. % and wherein the following equation is satisfied: 8 wt. %<Cr+Ti<40 wt. %, the balance being Fe and Ni, such intermediate coating layer being directly topped by a coating layer being an anticorrosion metallic coating.

Substrate provided with a plurality of layers, at least one of which includes metal oxides and is topped directly by a metal coating layer that contains at least 8% by weight nickel and at least 10% by weight chromium, the remainder being iron, additional elements and the impurities resulting from the fabrication process, wherein this metal coating layer is topped directly by an anticorrosion coating layer. A corresponding fabrication method is also provided.

Provided is a technique in which a reduction annealing method is used to efficiently produce a high-strength hot-dip galvanizing substrate or high-strength hot-dip galvannealing substrate, which is useful as a raw material for producing a high-strength plated steel sheet suppressed in the occurrence of bare spot. The substrate for hot-dip galvanizing or hot-dip galvannealing of the present invention satisfies the following condition: when the mapping intensity of Fe, which is obtained by using an electron probe microanalyser in a measurement field of view of 33.6 m41.4 m on the surface after reduction annealing, of 0 to 240 is divided into 16 parts at an interval of 15, the area occupied by a mapping intensity of 195 or more has 70% or more.

Provided is a ZnNi electroplated steel sheet having excellent corrosion resistance and formability and a manufacturing method therefor. The steel sheet includes: abase steel sheet; and a ZnNi plated layer formed on the base steel sheet, wherein a Ni alloying degree within the ZnNi plated layer is 7.5-14%, and the Ni amount is 40-50 atom % in a region within 1 pm toward the ZnNi plated layer from an interface of the base steel sheet and the ZnNi plated layer. Provided is a ZnNi electroplated steel sheet, which has superior corrosion resistance and formability despite having a relatively low nickel alloying degree, has excellent price competitiveness compared with that of a conventional ZnNi plated steel sheet and two-layer plated steel sheet, and can ensure high productivity.

Provided is a plated steel sheet often used as materials for vehicles, home appliances, construction and the like and, more specifically, to a plated steel sheet having a multilayer structure and a method for manufacturing the same.

Zn alloy plated steel material having excellent weldability and processed-part corrosion resistance and a method for production of Zn alloy plated steel material are provided. In the Zn alloy plated steel material comprising base steel material and a Zn alloy plating layer, the Zn alloy plating layer includes, by wt %, Al: 0.1-5.0%, Mg: 0.1-5.0%, as well as a remainder of Zn and inevitable impurities. The Zn alloy plated steel material includes a lower interface layer and an upper interface layer between the base steel material and the Zn alloy plating layer, wherein the lower interface layer is formed on the base steel material and has a dense structure, and the upper interface layer is formed on the lower interface layer and has a network-type or island-type structure.

A process for manufacturing a coated metal strip having a metallic corrosion protection coating is provided. The process includes passing a metal strip through a molten metal bath comprising from 2 to 8 wt % aluminum, 0 to 5 wt % magnesium, up to 0.3 wt % additional elements, and a balance including zinc and inevitable impurities, to yield a molten metal coated metal strip, wiping the molten metal coated metal strip with a nozzle spraying a gas on either side of the molten metal coated metal strip and cooling the coating in a controlled manner until the coating has completely solidified, to obtain the coated metal strip. A temperature of the molten metal bath is from 350 to 700 C., and the cooling is conducted at a rate less than 15 C./s between a temperature on leaving a unit where the wiping occurs and a start of solidification of the coating, and then at a rate greater than or equal to 15 C./s between a start and an end of solidification of the coating.

There is provided a hot-dip galvanized steel sheet and a hot-dip galvannealed steel sheet, which have excellent elongation properties, and methods for manufacturing the hot-dip galvanized steel sheet and the hot-dip galvannealed steel sheet. The present disclosure relates to a hot-dip galvanized steel sheet in which a hot-dip galvanized layer is formed on a surface of abase steel sheet, the hot-dip galvanized steel sheet having excellent elongation properties and being characterized by the composition and the microstructure thereof.

Provided is a ZnMg alloy plated steel material comprising: a base steel material; and first to third ZnMg alloy layers sequentially formed on the base steel material, wherein the first to third ZnMg alloy layers have a Zn single phase, a Mg single phase, a MgZn.sub.2 alloy phase, and a Mg.sub.2Zn.sub.11 alloy phase, an area rate of the MgZn.sub.2 alloy phase included in the first to third ZnMg alloy layers is larger than an area rate of the Mg.sub.2Zn.sub.11 alloy phase included in the first to third ZnMg alloy layers, and an area rate of a MgZn.sub.2 alloy phase included in each of the first to third ZnMg alloy layers is larger than an area rate of a MgZn.sub.2 alloy phase included in the second ZnMg alloy layer.