Posco

Posco Co., Ltd

Noroo Coil Coatings Co., Ltd.

Won-Ho Son

Myung-Soo Kim

Chang-Hoon Choi

Soo-Hyoun Cho

Jae-Duck Ko

Dong-Yun Kim

Jeong-Bong Yoon

Hee-Jea Eun

Jai-Ik Kim

Noi-Ha Cho

Jong-Hwa Kim

Seung-Hee Lee

Ki-Bong Kang

Ki-Duck Park

Hee-Man Son

Min-Ho Jo

Chan-Seok Bang

Young-Kwang Hong

Hong-Lea Cho

The present disclosure provides a solution composition having excellent acid corrosion resistance and adhesion to a steel sheet, a steel sheet surface-treated using the solution composition, and a method for manufacturing the steel sheet. Specifically, the present disclosure provides a solution composition for treating a surface of a steel sheet, the solution composition containing colloidal silica, alkoxy silane, a solvent, an acidity regulator, an acrylate-based monomer, an adhesion improver including a backbone formed of siloxane bonds, and a metal chelate curing agent, a steel sheet surface-treated using the solution composition, and a method for manufacturing the steel sheet.

Composition for surface treating of steel sheet, steel sheet using same, and manufacturing method of same

The present invention relates to a surface treatment composition comprising, on the basis of 100 wt % of the solid part of the composition, 20-40 wt % of a water-soluble polyurethane resin, 40-60 wt % of a silane-based sol-gel resin in which three types of silane compounds are cross-linked, 5-15 wt % of a curing agent, 0.5-1.5 wt % of a corrosion inhibitor, 0.1-1.0 wt % of a molybdenum-based compound, 1.0-3.0 wt % of a silane coupling agent; 1.0-2.0 wt % of an organometallic complex, 1.0-2.0 wt % of an acid scavenger, 0.1-1.0 wt % of an aluminum-based compound, and 1.0-2.0 wt % of a lubricant. A ternary hot-dip galvannealed steel sheet treated with a chromium-free surface treatment coating agent, according to an exemplary embodiment in the present invention, has excellent resistance to blackening, alkali and corrosion, and provides excellent effects without concern for problems, in chromium treatment, of additional equipment installation, an increase in manufacturing costs and environmental pollution.

Ternary hot-dip galvannealed steel sheet surface treatment solution composition for providing excellent blackening resistance and alkali resistance, ternary hot-dip galvannealed steel sheet surface-treated using same, and manufacturing method therefor

Provided is a composition for steel sheet surface coating, the composition comprising colloidal silica, a silane, a monomer, an organic resin, an acidity adjuster, a long-term corrosion-resistance improver, and a solvent; and a steel sheet coated with the composition. The steel sheet has excellent acid resistance, and maintains thickness uniformity thereof even when exposed to an acid for an extended period of time.

Composition for steel sheet surface coating and steel sheet surface-coated with same

Provided is a bilayer composition for surface treatment of a steel plate and a surface-treated steel plate using same. The bilayer composition for surface treatment of a steel plate, comprising an undercoat coating composition including 1 to 12 wt % of a phenoxy resin, 0.001 to 1.0 wt % of colloidal silica, 0.001 to 1.0 wt % of a silane coupling agent, 0.1 to 1.0 wt % of a corrosion inhibitor, 0.001 to 1.0 wt % of a phosphoric acid compound as a long-term corrosion resistance improving agent, and a balance of water; and a topcoat coating composition including 0.1 to 5.0 wt % of an acrylic acid resin, 30 to 50 wt % of colloidal silica, 40 to 60 wt % of alkoxy silane, 5 to 15 wt % of an acrylate-based monomer, 0.01 to 1.00 wt % of an acidity control agent, and a balance of an organic solvent.

Bilayer composition for surface treatment of steel plate and surface-treated steel plate using same

Provided is a composition for surface treatment of a steel sheet, the composition having excellent resistance to an acid, such as sulfuric acid, and to a coated steel sheet to which the composition for surface treatment is applied, wherein the composition for surface treatment comprises 30-50% wt % of colloidal silica containing 5-20 nm-sized silica, 40-60% wt % of silane containing three or more alkoxy groups, 5-15 wt % of an acrylate-based organic monomer, 0.01-1 wt % of an acid, and 1-15 wt % of a solvent.

Solution composition for surface treatment of steel sheet and surface-treated steel sheet using same

A surface treatment solution composition for forming an inorganic film, comprising: 10 to 30% by weight of a trivalent chromium compound containing chromium phosphate (A) and chromium nitrate (B) and satisfying a content ratio A/(A+B) of 0.3 to 0.6; 5 to 50% by weight of a silane compound; 0.2 to 3% by weight of a vanadium-based rust-inhibiting and corrosion-resisting agent; 0.5 to 5% by weight of a cobalt-based rust-inhibiting and corrosion-resisting agent; and 12 to 84.3% by weight of water, an alloyed hot-dip galvanized steel sheet surface-treated using the composition, and a method for manufacturing the alloyed hot-dip galvanized steel sheet, are provided, and the surface treatment solution composition containing the trivalent chromium compound has an excellent effect on corrosion resistance, blackening resistance, fuel resistance, weldability, and alkali resistance.

Solution composition containing trivalent chromium for surface treatment of steel sheet, galvanized steel sheet surface&#x2014;treated with same, and method for manufacturing galvanized

Provided is a surface-treating solution composition, a zinc-based plated steel sheet surface-treated using the same, and a method for producing the same, wherein the surface-treatment solution composition includes: 10 wt % to 20 wt % of a trivalent chromium compound containing chromium phosphate (A) and chromium nitrate (B), the content ratio thereof, A/(A+B), satisfying 0.3 to 0.6; 20 wt % to 40 wt % of a silane-based sol-gel resin in which three types of silane compounds are crosslinked; 0.2 wt % to 0.4 wt % of a rust-inhibiting and corrosion-resistant 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; 0.5 wt % to 2.0 wt % of an Al compound; and 25.3 wt % to 63.7 wt % of water. The zinc-based plated steel sheet surface-treated with the surface-treatment solution composition containing trivalent chromium has an excellent effect on corrosion resistance, blackening resistance, fingerprint resistance, piping oil infiltration, and alkali resistance.

Surface-treatment solution composition containing trivalent chromium and inorganic compound, zinc-based plated steel sheet surface-treated using same, and method for producing same

A cold rolled steel sheet, and a method of manufacturing the same, designed to have aging resistance and excellent formability suitable for use in automobile bodies, electronic appliances, and the like. The cold rolled steel sheet comprises in weight %: 0.003% or less of C, 0.003&#x2dc;0.03% of S, 0.01&#x2dc;0.1% of Al, 0.02% or less of N, 0.2% or less of P, at least one of 0.03&#x2dc;0.2% of Mn and 0.005&#x2dc;0.2% of Cu, and a balance of Fe and other unavoidable impurities. When the steel sheet comprises one of Mn and Cu, the composition of Mn, Cu, and S satisfies at least one relationship: 0.58*Mn/S&#x2266;10 and 1&#x2266;0.5*Cu/S&#x2266;10, and when the steel sheet comprises both Mn and Cu, the composition of Mn, Cu, and S satisfies the relationship: Mn+Cu&#x2266;0.3 and 2&#x2266;0.5*(Mn+Cu)/S&#x2266;20. Participates of MnS, CuS, and (Mn, Cu)S in the steel sheet have an average size of 0.2 &#x3bc;m or less. Since carbon content in a solid solution state in a crystal grain is controlled by fine precipitates of MnS, CuS, or (Mn, Cu)S, the steel sheet has enhanced aging resistance and formability, and has excellent yield strength and strength-ductility.

Cold rolled steel sheet having aging resistance and superior formability, and process for producing the same

Provided are a steel sheet for an automotive muffler and a method for producing the steel sheet. The steel sheet includes 0.01% by weight or less of C, 0.1 to 0.3% by weight of Si, 0.3 to 0.5% by weight of Mn, 0.015% by weight or less of P, 0.015% or less by weight of S, 0.02 to 0.05% by weight of Al, 0.004% or less of N, 0.2 to 0.6% by weight of Cu, 0.01 to 0.04% by weight of Co, and a remainder of Fe and unavoidable impurities. The method includes 0.01% by weight or less of C, 0.1 to 0.3% by weight of Si, 0.3 to 0.5% by weight of Mn, 0.015% by weight or less of P, 0.015% or less by weight of S, 0.02 to 0.05% by weight of Al, 0.004% or less of N, 0.2 to 0.6% by weight of Cu, 0.01 to 0.04% by weight of Co, and a remainder of Fe and unavoidable impurities, preparing a hot rolled steel sheet by re-heating the steel slab and by, during a finish rolling process, hot-rolling the steel slab at a temperature that is an Ar3 transformation temperature or more, preparing a cold rolled steel sheet by cold-rolling the hot rolled steel sheet with a cold reduction ratio of 50 to 90%, and performing a continuous annealing for the cold rolled steel sheet at a temperature of 500 to 900&#xb0; C.

Growing community of inventors

Pohang-si, South Korea

Won-Ho Son