Patent application number | Description | Published |
20130098507 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet is subjected to magnetic domain refinement by laser irradiation or electron irradiation and exhibits excellent low noise properties and low iron-loss properties when assembled into a real transformer device, by setting: the total tension (A) in rolling direction imparted to the steel sheet by the forsterite coating and the tension coating to be equal to or higher than 10.0 MPa; setting the total tension (B) in a direction orthogonal to the rolling direction imparted to the steel sheet by the forsterite coating and the tension coating to be equal to or higher than 5.0 MPa; and setting the total tension (A) and the total tension (B) to satisfy a formula shown below. | 04-25-2013 |
20130098508 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet (1) suppresses the content of Cr in the grain oriented electrical steel sheet to 0.1 mass % or less; (2) sets the coating weight of a forsterite coating, in terms of basis weight of oxygen therein, to at least 3.0 g/m | 04-25-2013 |
20130129984 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet has thickness of forsterite film at bottom portions of grooves formed on a surface of the steel sheet is ≧0.3 μm, groove frequency is ≦20%, abundance ratio of grooves crystal grains directly beneath themselves, each crystal grain having orientation deviating from Goss orientation by ≧10° and grain size ≧5 μm, total tension exerted on the steel sheet in the rolling direction by the forsterite film and tension coating is ≧10.0 MPa, total tension exerted on the steel sheet in a direction perpendicular to the rolling direction by the forsterite film and tension coating is ≧5.0 MPa and total tension satisfies 1.0≦A/B≦5.0, where A is total tension exerted in rolling direction by forsterite film and tension coating, and B is total tension exerted in direction perpendicular to rolling direction by forsterite film and tension coating. | 05-23-2013 |
20130129985 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet may reduce iron loss of material with linear grooves formed thereon for magnetic domain refinement and offer excellent low iron loss properties when assembled as an actual transformer, where the steel sheet has sheet thickness of 0.30 mm or less, linear grooves are formed at intervals of 2-10 mm in the rolling direction, the depth of each of the linear grooves is 10 μm or more, the thickness of the forsterite film at bottom portions of the linear grooves is 0.3 μm or more, total tension applied to the steel sheet by the forsterite film and tension coating is 10.0 MPa or higher in rolling direction, and the proportion of eddy current loss in iron loss W | 05-23-2013 |
20130130043 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet is subjected to magnetic domain refining treatment by electron beam irradiation and exhibits excellent low-noise properties when assembled as an actual transformer, in which a ratio (Wa/Wb) of a film thickness (Wa) of the forsierite film on a strain-introduced side of the steel sheet to a film thickness (Wb) of the forsierite film on a non-strain-introduced side of the steel sheet is 0.5 or higher, a magnetic domain discontinuous portion in a surface of the steel sheet on the strain-introduced side has an average width of 150 to 300 μm, and a magnetic domain discontinuous portion in a surface of the steel sheet on the non-strain-introduced side has an average width of 250 to 500 μm. | 05-23-2013 |
20130133783 | GRAIN ORIENTED ELECTRICAL STEEL SHEET - A grain oriented electrical steel sheet has a magnetic domain structure modified by strain introduction without a trace of treatment, in which noise generated when the grain oriented electrical steel sheet is used laminated on an iron core of a transformer is effectively reduced by: setting a magnetic flux density B | 05-30-2013 |
20130143003 | GRAIN ORIENTED ELECTRICAL STEEL SHEET - A grain oriented electrical steel sheet has sufficiently low iron loss and having less conventionally-concerned warpage of the steel sheet even after the steel sheet is subjected to artificial magnetic domain refining treatment, where strain-introducing treatment is conducted with high energy so that an iron loss-reducing effect can be maximized. The grain oriented electrical steel sheet is obtained by adjusting tension to be applied to a tension-applying insulating coating, or to both surfaces of the steel sheet by the tension-applying insulating coating, before strain-introducing treatment in the range of Formula (1): | 06-06-2013 |
20130143050 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet that is subjected to magnetic domain refining treatment by electron beam irradiation and exhibits excellent low-noise properties when assembled as an actual transformer in which tension exerted on the steel sheet by the forsterite film is 2.0 MPa or higher both in a rolling direction and a direction transverse (perpendicular) to the rolling direction, and a ratio of an irradiation pitch in a thermal strain introduced region (B) to a spot diameter (A) on an electron beam irradiation surface satisfies 0.5≦B/A≦5.0. | 06-06-2013 |
20130160901 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet has linear grooves for magnetic domain refinement formed on a surface thereof and may reduce iron loss by using these linear grooves, where the proportion of those linear grooves having crystal grains directly beneath themselves, each crystal grain having an orientation deviating from the Goss orientation by 10° or more and a grain size of 5 μm or more, is controlled to 20% or less, and secondary recrystallized grains are controlled to have an average β angle of 2.0° or less, and each secondary recrystallized grain having a grain size of 10 mm or more is controlled to have an average β-angle variation of 1° to 4°. | 06-27-2013 |
20130161301 | DEVICE TO IMPROVE IRON LOSS PROPERTIES OF GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR IMPROVING IRON LOSS PROPERTIES OF GRAIN ORIENTED ELECTRICAL STEEL SHEET - A device reduces dust for safely preventing laser-irradiation capacity from decreasing due to contamination and reliably reducing iron loss of a grain oriented electrical steel sheet. The device improves iron loss properties of a grain oriented electrical steel sheet by irradiating its surface with laser to reduce iron loss, wherein, distance between a laser beam emission port and a laser irradiation point is L (mm); laser irradiation angle formed by a line linking the emission port and the irradiation point with respect to a direction vertical to the sheet is θ (°); and L≧50, the emission port is positioned such that L and θ satisfy: | 06-27-2013 |
20130167982 | METHOD FOR MANUFACTURING GRAIN ORIENTED ELECTRICAL STEEL SHEET - A method of manufacturing a grain oriented electrical steel sheet includes subjecting a steel slab to rolling to obtain a steel sheet, subjecting the steel sheet to decarburizing annealing, coating of an annealing separator mainly composed of MgO onto a surface of the steel sheet, and final annealing to obtain a grain oriented electrical steel sheet having at least 4.0 g/m | 07-04-2013 |
20130206283 | GRAIN ORIENTED ELECTRICAL STEEL SHEET AND METHOD FOR MANUFACTURING THE SAME - A grain oriented electrical steel sheet has thermal strain introduced thereinto in a dotted-line arrangement in which strain-imparted areas are lined in a direction that crosses a rolling direction of the steel sheet, wherein the strain-imparted areas introduced in the dotted-line arrangement have a size from 0.10 mm or more to 0.50 mm or less and an interval between the adjacent strain-imparted areas is from 0.10 mm or more to 0.60 mm or less. | 08-15-2013 |
20140234638 | GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND MANUFACTURING METHOD THEREOF - A grain-oriented electrical steel sheet to which electron beam irradiation is applied, has a film and a thickness of t (mm), wherein no rust is produced on a surface of the steel sheet after a humidity cabinet test lasting 48 hours at a temperature of 50° C. in an atmosphere of 98% humidity, and iron loss W | 08-21-2014 |
20140338792 | GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND METHOD OF MANUFACTURING SAME - A grain-oriented electrical steel sheet allows for manufacture of a transformer that exhibits, when the steel sheet is applied to an iron core thereof, extremely low iron loss and extremely low noise properties, makes highly efficient use of energy, and can be used in various environments. The grain-oriented electrical steel sheet has a strain distribution in regions where closure domains are formed, when observed in a cross section in the rolling direction, with a maximum tensile strain in a sheet thickness direction being 0.45% or less, and with a maximum tensile strain t (%) and a maximum compressive strain c (%) in the rolling direction satisfying Expression (1): | 11-20-2014 |
20140352849 | GRAIN-ORIENTED ELECTRICAL STEEL SHEET - The present invention proposes a method that can reduce the noise generated by a transformer core and the like when formed by laminations of a grain-oriented electrical steel sheet in which core loss has been reduced by a magnetic domain refinement process. In this steel sheet, linear distortion extending with an orientation in which an angle formed with a direction perpendicular to the rolling direction of the steel sheet is an angle of 30° or less is periodic in the direction of rolling of the steel sheet, core loss (W | 12-04-2014 |
20140360629 | GRAIN-ORIENTED ELECTRICAL STEEL SHEET AND METHOD OF MANUFACTURING THE SAME - A grain-oriented electrical steel sheet, on which magnetic domain refining treatment by strain application has been performed, has an insulating coating with excellent insulation properties and corrosion resistance. In a grain-oriented electrical steel sheet, linear strain having been applied thereto by irradiation with a high-energy beam, the linear strain extending in a direction that intersects a rolling direction of the steel sheet, an area ratio of irradiation marks within an irradiation region of the high-energy beam is 2% or more and 20% or less, an area ratio of protrusions with a diameter of 1.5 μm or more within a surrounding portion of the irradiation mark is 60% or less, and an area ratio of exposed portions of steel substrate in the irradiation mark is 90% or less. | 12-11-2014 |