Kawasaki Steel Corporation

Jfe Steel Corporation

Yuka Komori

Masaki Kawano

Hideo Kobayashi

Michiro Komatsubara

Yasuyuki Hayakawa

Mitsumasa Kurosawa

Kazumichi Sashi

Kazuaki Tamura

Norio Kosuge

Keiji Sato

Atsuhito Honda

Akio Fujita

Tomofumi Shigekuni

Yasuo Yokoyama

Masaaki Kohno

Taizo Mohri

Katuro Yamaguchi

In a process for manufacturing a coated steel sheet such as a coated electromagnetic steel sheet using a water-based coating liquid containing an organic resin, to perform steps subsequent to an annealing step continuously at high speed without causing appearance defects such as coating unevenness; to provide an electromagnetic steel sheet having an insulating film thereon, in which properties of the film are satisfactory, superior weldability and punchability can be obtained without deteriorating the space factor, and the satisfactory film properties can be maintained even if the electromagnetic steel sheet having the insulating film thereon is temper-rolled. A coating liquid is applied onto an untreated steel sheet. The applied liquid is heated on the side close to the steel sheet in such a manner that the time elapsed until the steel sheet temperature is increased to 100&#xb0; C. after the application is completed is 10 seconds or less, thereby drying the coating liquid. The steel sheet temperature is further increased to a predetermined temperature, thereby forming a coating film. When insulating films for electromagnetic steel sheets are formed, the coating liquid preferably further contains a water based inorganic component.

Method for producing coated steel sheet

A magnetic steel sheet with an insulating coating having a good punchability, high sliding performance, excellent handleability in processing, and good uniformity and adhesiveness is achieved by forming a chromium-free insulating coating containing 20 parts by mass or more and 90 parts by mass or less of fluorocarbon resin as a top layer coating of the magnetic steel sheet, and preferably making the kinetic friction coefficient of a surface of the insulating coating 0.3 or less.

Electrical sheet having insulating coating and insulating coating

Electrical steel sheet can be produced by baking at low temperatures and is capable of stress relief annealing and has excellent solvent resistance and has an insulating coating containing substantially no chromium components harmful to environment; the electrical steel sheet has an insulating coating comprising a resin and an inorganic colloid which is silica, alumina or alumina-containing silica.

Solvent-resistant electrical steel sheet capable of stress relief annealing and process

Non-oriented magnetic steel sheets, which are mainly used as materials for iron cores for use in electric apparatuses, have a low iron loss and a high magnetic flux density at the same time. The non-oriented magnetic steel sheet comprises from about 1.5 to about 8.0 weight % Si, from about 0.005 to about 2.50 weight % Mn, and not more than about 50 ppm each of C, S, N, O, and B, in which a crystal orientation parameter <&Ggr;> is 0.200 or less. In addition, the average crystal grain diameter is preferably from about 50 to about 500 &mgr;m, and an areal ratio of crystal grains on a surface of the steel sheet is preferably 20% and less, in which crystal plane orientations of the crystal grains are within 15&deg; from the <111> axis. In addition, the non-oriented magnetic steel sheet preferably contains small amounts of elements such as Al, Sb, Ni, Sn, Cu, P, and Cr. The manufacturing method for the non-oriented magnetic steel is also described.

Non-oriented magnetic steel sheet having low iron loss and high magnetic flux density and manufacturing method therefor

An electromagnetic steel sheet having a corrosion-resistant electrically insulating film. The insulating film is formed by spraying and baking, on the steel sheet, a treating liquid containing an emulsion of fine resin particles, a reducing agent and an accelerator. The emulsion of fine resin particles exhibits a weight change peak temperature of not lower than about 400.degree. C. as measured by differential thermal weight measurement conducted while raising the emulsion temperature at a constant rate of temperature rise. The emulsion also substantially resists when contacted by phosphoric acid. The reducing agent is a phosphate ion aqueous solution containing a metal. Also disclosed is a corrosion-resistant core made from the electromagnetic steel sheet.

Electromagnetic steel sheet and a core made therefrom

An electromagnetic steel sheet has an electrically insulating coating with superior weldability, formed by coating a treatment solution on the electromagnetic steel sheet and baking the same, the treatment solution containing a synthetic resin fine-particle emulsion having resistance against chromic and/or bichromic acid and exhibiting a peak temperature not lower than 400.degree. C. at which a weight change rate is maximized when a sample is heated at a constant rate in differential thermal gravimetry, a chromate and/or bichromate base aqueous solution containing at least one kind of two-valence metal, and an organic reducer. The steel sheet is superior in electrical insulation, adhesion, punching ability, weldability and corrosion resistance.

Electromagnetic steel sheet having an electrically insulating coating

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Okayama, Japan

Yuka Komori