Abstract: This electrical steel sheet includes a base steel sheet, a first insulation coating formed on a first surface of the base steel sheet and having adhesiveness, and a second insulation coating formed on a second surface of the base steel sheet which is a back surface to the first surface and having adhesiveness, in which an average pencil hardness of the first insulation coating is HB or higher and 3 H or lower, and an average pencil hardness of the second insulation coating is higher than the average pencil hardness of the first insulation coating.

Abstract: This coating composition for an electrical steel sheet is a coating composition for an electrical steel sheet containing an epoxy resin, a high-temperature curing agent, and inorganic fine particles, wherein a content of the high-temperature curing agent with respect to 100 parts by mass of the epoxy resin is 5 to 30 parts by mass, wherein the inorganic fine particles are one or more selected from metal hydroxides, metal oxides that react with water at 25° C. to become metal hydroxides and silicate minerals having a hydroxyl group, wherein the volume average particle diameter of the inorganic fine particles is 0.05 to 2.0 ?m, wherein a content of the epoxy resin with respect to a total mass of the coating composition for an electrical steel sheet is 45 mass % or more, and wherein a content of the inorganic fine particles with respect to 100 parts by mass of the epoxy resin is 1 to 100 parts by mass.

Abstract: Provided is a method of manufacturing a laminated core by punching electrical steel strips including an insulation coating to obtain core single sheets and laminating the core single sheets, the method including: pressurizing two or more electrical steel strips using a guide roller to temporarily bond the electrical steel strips immediately before the punching; and obtaining the core single sheets by performing the punching after inserting the two or more electrical steel strips after the temporary bonding into a punching die.

Abstract: This electrical steel sheet includes a base steel sheet, a first insulation coating formed on a first surface of the base steel sheet and having adhesiveness, and a second insulation coating formed on a second surface of the base steel sheet which is a back surface to the first surface and having adhesiveness, in which an average pencil hardness of the first insulation coating is HB or higher and 3H or lower, and an average pencil hardness of the second insulation coating is higher than the average pencil hardness of the first insulation coating.

Abstract: A grain-oriented electrical steel sheet has a steel sheet and an insulating coating which is formed on a surface of the steel sheet. In the insulating coating, a metal phosphate and a colloidal silica are contained, the colloidal silica is contained in an amount of 20 to 150 parts by mass with respect to 100 parts by mass of the metal phosphate, one or more kinds of fine particles selected from the group consisting of silicon carbide, silicon nitride, aluminum nitride, boron nitride, sialon, and cordierite are further contained in an amount of 0.5 to 7 parts by mass with respect to 100 parts by mass of the metal phosphate, an average particle size of the fine particles is 0.3 to 7.0 ?m, crystallized ratio of the metal phosphate is 2% to 40%, and chromium is not contained.

Abstract: A coating solution for forming an insulating film for a grain-oriented electrical steel sheet which contains one or more types of hydrous silicate powders having an average particle size of 2 ?m or less, and one or more types of phosphoric acids and phosphates satisfying a relation of ?niMi/?Pi?0.5, and satisfies (Formula 1). 1.5?(?niMi+?n?jM?j)/?Pi?15??(Formula 1) (P represents the number of moles of phosphorus, M represents the number of moles of metal ions derived from the phosphate, n represents the valence of the metal ions derived from the phosphate, i represents the number of types of phosphates, M? represents the number of moles of metal elements in the hydrous silicate, n? represents the valence of the metal elements in the hydrous silicate, and j represents the number of types of hydrous silicates).

Abstract: There is provided a non-oriented electrical steel sheet that includes a base metal steel sheet and an insulating coating film that is formed on a surface of the base metal steel sheet, wherein the insulating coating film mainly contains metal phosphate, organic resin, and water-soluble organic compound, the water-soluble organic compound has an SP value that is within a range of 10.0 to 20.

Abstract: There is provided a non-oriented electrical steel sheet that includes a base metal steel sheet and an insulating coating film that is formed on a surface of the base metal steel sheet, wherein the insulating coating film mainly contains metal phosphate, organic resin, and water-soluble organic compound, the metal phosphate contains at least aluminum as a metallic element, the organic resin has an SP value being within a range of 18.0 (MPa)0.5 or more to less than 24.0 (MPa)0.5, the water-soluble organic compound has an SP value being within a range of 19.0 (MPa)0.5 or more to less than 35.0 (MPa)0.5, and when measurement by X-ray diffractometry is performed on the insulating coating film, a degree of crystallinity of aluminum phosphate calculated from a peak from the metal phosphate is within a range of 0.5 to 5.0%.

Abstract: A scale composition determination device (10) determines that Fe2O3 has been generated in the outermost layer of a scale (SC) in the case where at least one of spectral emissivities at one wavelength and the other wavelength that are measured by radiometers for spectral emissivity measurement (21a, 21b) is not within a predetermined range including spectral emissivities of FeO at one wavelength and the other wavelength, and determines that Fe2O3 has not been generated in the outermost layer of the scale (SC) in the case where all of the spectral emissivities at one wavelength and the other wavelength that are measured by the radiometers for spectral emissivity measurement (21a, 21b) is within the predetermined range including the spectral emissivities of FeO at one wavelength and the other wavelength.

Abstract: A non-oriented electrical steel sheet according to one embodiment of this invention includes a base metal steel sheet and a composite coating film composed of a Zn-containing phosphate and an organic resin, the composite coating film being formed on a surface of the base metal steel sheet. A molar ratio of Zn to all metal components in the composite coating film is 10 mol % or more, and after the non-oriented electrical steel sheet is boiled for 20 minutes in boiled distilled water, an amount of soluble Zn in the distilled water is 1.0 mg/m2 or more. The method for determining the amount of soluble Zn is in accordance with JIS K 0102: 2016 “Testing Methods for Industrial Wastewater”, 53.3 “ICP Emission Spectroscopy”.

Abstract: A scale composition determination device (10) determines that Fe2O3 has been generated in the outermost layer of a scale (SC) in the case where the absolute value of a difference between temperatures of a steel material SM measured by radiation thermometers (20a, 20b) is equal to or more than a predetermined temperature, and determines that Fe2O3 has not been generated in the outermost layer of the scale (SC) in the case where the absolute value of the difference between the temperatures of the steel material SM measured by the radiation thermometers (20a, 20b) is not equal to or more than the predetermined temperature.

Abstract: A solution for forming an insulation coating of grain-oriented electrical steel sheet includes an aqueous solution prepared by mixing a phosphate solution and colloidal silica. Chromium is not added to the aqueous solution. The colloidal silica includes silica particles surface-modified by an aluminate or is prepared by adding an aluminate to colloidal silica such as conventional colloidal silica.

Abstract: An insulating coating for an electrical steel sheet is provided that is formed on a surface of a base metal of the electrical steel sheet and that contains a polyvalent metal phosphate of one or more elements selected from Al, Zn, Mg and Ca, and has an enriched layer of a divalent metal at an interface with the surface of the base metal. An enrichment of the divalent metal contained in the enriched layer is 0.01 g/m2 or more and less than 0.2 g/m2.

Abstract: Provided are: a metalworking oil composition having excellent workability and rust inhibiting performance, which is prepared by blending (A) at least one carboxylate selected from a polyhydric alcohol ester of a monocarboxylic acid and a monohydric alcohol ester of a polycarboxylic acid, (B) a phosphorus-containing compound, and (C) a rust inhibitor, wherein the monocarboxylic acid has 9 or more and 21 or less carbon atoms, and the content of the carboxylate is 0.6% by mass or more based on the total amount of the composition; and a metalworking method using the composition.

Abstract: [Problem] To provide: a coating liquid for forming an insulation coating for grain-oriented electrical steel sheets, which enables the achievement of excellent coating properties including high coating tension and excellent corrosion resistance even without using a chromium compound; a grain-oriented electrical steel sheet; and a method for producing a grain-oriented electrical steel sheet. [Solution] A coating liquid for forming an insulation coating for grain-oriented electrical steel sheets, which contains boric acid and hydrated silicate particles containing aluminum.

Abstract: A scale composition determination device (10) determines that Fe2O3 has been generated in the outermost layer of a scale (SC) in the case where the absolute value of a difference between temperatures of a steel material SM measured by radiation thermometers (20a, 20b) is equal to or more than a predetermined temperature, and determines that Fe2O3 has not been generated in the outermost layer of the scale (SC) in the case where the absolute value of the difference between the temperatures of the steel material SM measured by the radiation thermometers (20a, 20b) is not equal to or more than the predetermined temperature.

Abstract: A grain-oriented electrical steel sheet according to one embodiment of the present invention includes a steel sheet and an insulation coating, in which the insulation coating contains a first metal phosphate, which is a metal phosphate of one or two more metals selected from Al, Fe, Mg, Mn, Ni, and Zn; a second metal phosphate, which is a metal phosphate of one or two more metals selected from Co, Mo, V, W, and Zr; and colloidal silica, the insulation coating does not contain chromate, and an elution amount of phosphoric acid of the insulation coating as determined by boiling the grain-oriented electrical steel sheet in a boiled pure water for 10 minutes, then measuring an elution amount of phosphoric acid into the pure water, and dividing the amount of phosphoric acid by the area of the insulation coating of the boiled grain-oriented electrical steel sheet is 30 mg/m2 or less.

Abstract: A scale composition determination device (10) determines that Fe2O3 has been generated in the outermost layer of a scale (SC) in the case where the absolute value of a difference between temperatures of a steel material SM measured by radiation thermometers (20a, 20b) is equal to or more than a predetermined temperature, and determines that Fe2O3 has not been generated in the outermost layer of the scale (SC) in the case where the absolute value of the difference between the temperatures of the steel material SM measured by the radiation thermometers (20a, 20b) is not equal to or more than the predetermined temperature.

Abstract: In the present invention, there is provided a coating liquid for forming an insulation coating for a grain-oriented electrical steel sheet, including: a solvent; and one or two more layered clay mineral powders having a specific surface area of 20 m2/g or more. In addition, in the present invention, there is provided a grain-oriented electrical steel sheet including: a base metal; and an insulation coating provided on a surface of the base metal, in which the insulation coating contains SiO2, and one or two of Al2O3 and MgO, and has a porosity of 10% or less.

Abstract: A coating solution for forming an insulating film for a grain-oriented electrical steel sheet which contains one or more types of hydrous silicate powders having an average particle size of 2 ?m or less, and one or more types of phosphoric acids and phosphates satisfying a relation of ?niMi/?Pi?0.5, and satisfies (Formula 1). 1.5?(?niMi+?n?jM?j)/?Pi?15 . . . (Formula 1) (P represents the number of moles of phosphorus, M represents the number of moles of metal ions derived from the phosphate, n represents the valence of the metal ions derived from the phosphate, i represents the number of types of phosphates, M? represents the number of moles of metal elements in the hydrous silicate, n? represents the valence of the metal elements in the hydrous silicate, and j represents the number of types of hydrous silicates).