Jfe Steel Corporation

Kawasaki Steel Corporation

Kansai Paint Company, Ltd.

Nobue Fujibayashi

Kazumichi Sashi

Chiyoko Tada

Nobuko Nakagawa

Naoki Muramatsu

Takahiro Kubota

Kazuaki Kyono

Satoru Ando

Nobuo Totsuka

Takashi Nakano

Kenichi Sasaki

Akira Matsuzaki

Masayasu Nagoshi

Nobuyuki Morito

Yasuhide Oshima

Hiroyuki Ogata

Naoki Nishiyama

Tomofumi Shigekuni

Toru Imokawa

Jun Akui

Etsuo Hamada

Yusuke Okumura

Makoto Isobe

Rie Kaneko

Syuji Nomura

Yoshikazu Morohoshi

Takashi Okubo

Motonori Miyaoka

An electrical steel sheet provided with an insulating coating wherein the insulating coating is formed by a method includes forming an insulating coating on an electrical steel sheet, including: preparing a treatment solution that does not contain an Fe compound by adding an Si compound to water; applying the treatment solution to a surface of the electrical steel sheet; leaving the treatment solution on the surface of the electrical steel sheet to allow Fe in the electrical steel sheet to be dissolved in the treatment solution; and baking the treatment solution to form the insulating film such that a coating weight of Si in the insulating coating in terms of SiOis 50% to 99% of the total coating weight, and a ratio (Fe/Si) of content of Fe to content of Si in the insulating coating is 0.01 to 0.6 on a molar basis.

Method of making an electrical steel sheet provided with insulating coating

A method for forming an insulating coating on an electrical steel sheet is provided. The method includes preparing a treatment solution by adding a Si compound to water and applying the treatment solution to a surface of the electrical steel sheet. Fe in the electrical steel sheet dissolves in the treatment solution and, thereafter, the electrical steel sheet and treatment solution are baked to form the insulating film. In the insulating film, a coating weight of Si in terms of SiOis 50% to 99% of the total coating weight, and a ratio (Fe/Si) of content of Fe to content of Si in the insulating coating is 0.01 to 0.6 on a molar basis.

An electrical steel sheet is provided with insulating coating. The insulating coating contains Si and Fe. The coating weight of Si in the insulating coating in terms of SiOis 50% to 99% of the total coating weight. The ratio (Fe/Si) of the content of Fe to the content of Si in the insulating coating is 0.01 to 0.6 on a molar basis. The ratio (C (the organic resin+the lubricant)/(FeO+SiO)) of the coating weight of the organic resin and/or the lubricant in terms of C to the sum of the coating weight of Fe in terms of FeOand the coating weight of Si in terms of SiOpreferably is 0.05 to 0.8.

Electrical steel sheet provided with insulating coating

A semi-organic insulation coating includes an inorganic component and an organic resin, a Zr compound and an Si compound contains a plate-like silica as an inorganic component and are included in a ratio in a dry coating of 20 to 70 mass % of Zr compound (converted to ZrO) and 10 to 50 mass % of Si compound containing plate-like silica (converted to SiO), and the remainder is substantially an organic resin, whereby a magnetic steel sheet with a semi-organic insulation coating has no deterioration of corrosion resistance and water resistance without containing a chromium compound and being excellent in powdering resistance, scratch resistance, sticking resistance, TIG weldability, punchability and coating appearance.

Magnetic steel sheet with semi-organic insulation coating

The present invention provides a chromium-free surface treatment agent, comprising: a resin compound having a specific bisphenol skeleton; cationic urethane resin emulsion; silane coupling agent; an organic titanium chelate compound; a quadrivalent vanadyl compound; a molybdic acid compound; and water, wherein these components are blended at predetermined ratios such that pH value of the surface treatment agent is in the range of 4 to 5. The one-pack type chromium-free surface treatment agent of the present invention exhibits good stability during storage and is capable of forming on a metal material surface a coating film excellent in corrosion resistance at a bending-processed portion of a steel sheet, solvent resistance and paintability after alkali degreasing.

Surface treatment agent for zinc or zinc alloy coated steel sheet, zinc or zinc alloy coated steel sheet, and method of producing the steel sheet

A method of producing a hot-dip galvanized steel sheet includes applying, to a hot-dip galvanized steel sheet having a Ra of 0.5 to 2.0 &#x3bc;m and a PPI of 150 or more, a predetermined surface treatment agent, i.e., a surface treatment agent containing a specified resin compound, a specified urethane resin having cationy, a specified silane coupling agent having a functional group, a specified organic Ti chelate compound, and a tetravalent vanadyl compound at a specified ratio; and drying the surface treatment agent at a ultimate sheet temperature of 50&#xb0; C. to 180&#xb0; C. to form a surface treatment coating film with a coating weight of 0.2 to 1.0 g/mon the surface of the steel sheet.

Hot-dip galvanized steel sheet and method for producing the same

A surface-treatment agent contains a resin compound having a specific bisphenol skeleton, a cationic urethane resin emulsion, a silane coupling agent, an organic titanium chelate compound, a tetravalent vanadyl compound, and water, with predetermined proportions and having a pH of 4 to 5; a method for producing a coated steel sheet using the surface-treatment agent; and a coated steel sheet.

Surface-treatment agent, method for producing coated steel sheet using the surface-treatment agent, and coated steel sheet

A surface-treated steel sheet is disclosed, including a zinc based plated steel sheet having thereon a surface-treated film containing titanium, nickel, aluminum and fluorine and having a film thickness of from 0.05 to 1.0 &#x3bc;m, the surface-treated film having a titanium deposition amount of from 0.01 to 0.5 g/mand containing from 0.01 to 5 parts by mass of nickel, from 0.1 to 25 parts by mass of aluminum and from 1 to 500 parts by mass of fluorine relative to 100 parts by mass of titanium. This surface-treated steel sheet does not contain hexavalent chromium in the film thereof at all and has excellent heat discoloration resistance, corrosion resistance and resistance to blackening.

Surface-treated steel sheet

A galvannealed steel sheet having excellent surface appearance and press formability, characterized in that a steel sheet comprises a galvannealed layer at least one surface of the steel sheet, the steel sheet comprising 0.001 to 0.005% by mass of C, 0.010 to 0.040% by mass of Si, 0.05 to 0.25% by mass of Mn, and 0.010 to 0.030% by mass of P, wherein the Si, Mn, and P satisfy the relation 0.030%&#x2266;Si+P+Mn/20&#x2266;0.070%, and its production method.

Alloyed zinc dip galvanized steel sheet

Zinc and zinc-alloy hot-dip-coated steel sheet having decreased bare

Method for hot dip galvanizing high tensile steel strip with minimal

Growing community of inventors

Chiba, Japan

Nobue Fujibayashi