Grain-oriented electrical steel sheet, iron core of transformer, transformer, and method for reducing noise of transformer
AssigneeJfe Steel Corporation
InventorsTakashi Terashima, Makoto Watanabe, Toshito Takamiya, Tomoyuki Okubo
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Abstract
A grain-oriented electrical steel sheet having an insulating film disposed on a surface thereon. The insulating film having a chemical composition comprising Si, P, O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, Mn, and Co. The insulating film has a crystallinity in a range of 20% or more, and a minimum tension provided to the steel sheet by the insulating film at a temperature in a range of 100° C. to 200° C. is 10 MPa or more.
Claims20
A grain-oriented electrical steel sheet having an insulating film disposed on a surface thereon, the insulating film having a chemical composition comprising Si, P, O, and at least one selected from the group consisting of Mg, Ca, Ba, Sr, Zn, Al, Mn, and Co,
- wherein the insulating film includes 20% or more of a crystal phase, the crystal phase consisting of one of Zr2P2O7, (MgCo)2P2O7, Co2P2O7, cordierite, β-spodumene, quartz, zircon, a zirconium phosphate-based crystal phase, or a tungsten phosphate-based crystal phase, and
- a minimum tension provided to the steel sheet by the insulating film at a temperature in a range of 100° C. to 200° C. is 10.5 MPa or more.
Dependencies are inferred from the claim text.