Abstract: The present invention relates to a steel sheet with improved yellowing resistance and phosphatability, wherein the steel sheet contains 0.5% by weight or more of Mn, and contains 0.01 to 10 mg/m2 of Ca+Mg, 0.01 to 10 mg/m2 of P, 0.01 to 20 mg/m2 of C, and 0.05 to 30 mg/m2 of O as components excluding a steel component on the surface of the steel sheet after pickling, water rinsing, and drying. According to the present invention, in a manufacturing process of the steel sheet, the surface of the steel sheet is subjected to a chemical conversion treatment for improving phosphatability and yellowing resistance in a water-cooling section or a water-washing section, thereby having an effect of improving the surface quality of products using same and various subsequently treated products.

Abstract: A composition for washing a pickled steel plate and a method for washing a pickled steel plate using the same are provided. The composition for washing a pickled steel plate includes a phosphoric acid ester compound, an amine-based compound, sodium carbonate, ammonium acetate, ethylene diamine tetraacetic acid (EDTA) and a remainder of water, and the method for washing a pickled steel plate is performed using the same.

Abstract: A composition for washing a pickled steel plate and a method for washing a pickled steel plate using the same are provided. The composition for washing a pickled steel plate includes a phosphoric acid ester compound, an amine-based compound, sodium carbonate, ammonium acetate, ethylene diamine tetraacetic acid (EDTA) and a remainder of water, and the method for washing a pickled steel plate is performed using the same.

Abstract: A composition for washing a pickled steel plate and a method for washing a pickled steel plate using the same are provided. The composition for washing a pickled steel plate includes a phosphoric acid ester compound, an amine-based compound, sodium carbonate, ammonium acetate, ethylene diamine tetraacetic acid (EDTA) and a remainder of water, and the method for washing a pickled steel plate is performed using the same.

Abstract: A composition for washing a pickled steel plate and a method for washing a pickled steel plate using the same are provided. The composition for washing a pickled steel plate includes a phosphoric acid ester compound, an amine-based compound, sodium carbonate, ammonium acetate, ethylene diamine tetraacetic acid (EDTA) and a remainder of water, and the method for washing a pickled steel plate is performed using the same.

Abstract: Provided is a method for producing plated steel sheet by means of an annealing device which includes at least one section and in which the at least one section is filled with a gas constituting a non-reducing atmosphere or a weakly reducing atmosphere to substantially improve the quality of plating onto hot-dipped steel sheet, including the plating properties, alloying properties, anti-pickup properties, plating adhesion properties, anti-flaking properties, anti-cratering properties and anti-ash properties, by using prior-art annealing equipment and heat-treatment cycle without any additional oxidation-reduction heat treatment process or large quantities of high-cost alloying elements.

Abstract: There is provided a method and apparatus for plating high strength steel such as advanced high strength steel (AHSS) after irradiating the high strength steel with at least one of laser light and plasma to remove Si/Mn/Al oxides from the surface of the high strength steel, modify the surface of the high strength steel, or make the surface of the high strength steel suitable for a post process such as a zinc plating process. For this, a plating method includes heating high strength steel; treating a surface of the high strength steel with plasma to remove at least one of a Mn oxide, an Al oxide, and an Si oxide formed on the surface of the high strength steel during the heating of the high strength steel; and plating the surface-treated high strength steel.

Abstract: Provided is a method for producing plated steel sheet by means of an annealing device which includes at least one section and in which the at least one section is filled with a gas constituting a non-reducing atmosphere or a weakly reducing atmosphere to substantially improve the quality of plating onto hot-dipped steel sheet, including the plating properties, alloying properties, anti-pickup properties, plating adhesion properties, anti-flaking properties, anti-cratering properties and anti-ash properties, by using prior-art annealing equipment and heat-treatment cycle without any additional oxidation-reduction heat treatment process or large quantities of high-cost alloying elements.

Abstract: Provided are an organic-inorganic hybrid coating solution composition including 12 wt % to 36 wt % of a urethane-acryl hybrid resin, 8 wt % to 24 wt % of a nanosilicate-phenoxy hybrid resin, and 40 wt % to 80 wt % of an inorganic-based anti-corrosion agent based on a solid content, and an organic-inorganic hybrid coated steel sheet having a coating layer formed with the coating solution composition. A coating solution composition having excellent solution stability and a coated steel sheet having improved corrosion resistance, solvent resistance, and conductivity may be provided.

Abstract: There is provided a method and apparatus for plating high strength steel such as advanced high strength steel (AHSS) after irradiating the high strength steel with at least one of laser light and plasma to remove Si/Mn/Al oxides from the surface of the high strength steel, modify the surface of the high strength steel, or make the surface of the high strength steel suitable for a post process such as a zinc plating process. For this, a plating method includes heating high strength steel; treating a surface of the high strength steel with plasma to remove at least one of a Mn oxide, an Al oxide, and an Si oxide formed on the surface of the high strength steel during the heating of the high strength steel; and plating the surface-treated high strength steel.

Abstract: Provided is a hot dip plated steel sheet used in automotive materials and a method of manufacturing the same, and more particularly, to a hot dip plated steel sheet having excellent platability and plating adhesiveness in which a steel sheet containing alloying elements forming oxides on a surface of the steel sheet at high temperatures is used as an underlying steel sheet, and a method of manufacturing the same. According to the present invention, a hot dip plated steel sheet having excellent platability and plating adhesiveness is provided, in which a steel sheet containing alloying elements forming oxides on a surface of the steel sheet at high temperatures is used as an underlying steel sheet, and thus, limitations in added amounts of silicon (Si), manganese (Mn), or aluminum (Al) may be mitigated. Therefore, development of new steels may be accelerated.

Abstract: Provided is an annealing device which comprises at least one section and in which the at least one section is filled with a gas constituting a non-reducing atmosphere or a weakly reducing atmosphere, as well as a device for producing plated steel sheet comprising the annealing device, and a method for producing plated steel sheet by means of such a device to substantially improve the quality of plating onto hot-dipped steel sheet, including the plating properties, alloying properties, anti-pickup properties, plating adhesion properties, anti-flaking properties, anti-cratering properties and anti-ash properties, by using prior-art annealing equipment and heat-treatment cycle without any additional oxidation-reduction heat treatment process or large quantities of high-cost alloying elements.

Abstract: A chrome free composition for metal surface treatment and a surface-treated metal sheet can provide excellent characteristics of high conductivity, corrosion resistance, alkali resistance, and high temperature and humidity resistance. The composition includes a vinyl based binder resin, an acryl based binder resin, and a solvent. In the vinyl based binder resin, a corrosion-resistant inorganic material is combined, and an amount of the vinyl based binder resin is in a range of 10 weight % to 70 weight % with respect to a total solid content. In the acryl based binder resin, a corrosion-resistant inorganic material is combined, and an amount of the acryl based binder resin is in a range of 15 weight % to 75 weight % with respect to the total solid content. An amount of the corrosion resistance inorganic material is in a range of 3 weight % to 25 weight % with respect to a total solid content.