# US 2020/0399732 A1 · Grain-oriented electrical steel sheet and method for producing thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0399732 A1 - Document ID: US20200399732A1 - Status: Published application - Kind: A1 - Application number: 16/979,110 - Filed: 2019-03-19 - Published: 2020-12-24 - Earliest claimed: 2018-03-20 - Assignees: Nippon Steel Corporation - Applicants: Nippon Steel Corporation - Inventors: Takashi KATAOKA; Nobusato MORISHIGE; Haruhiko ATSUMI; Kazutoshi TAKEDA; Shin FURUTAKU; Hirotoshi TADA; Ryosuke TOMIOKA - Web page: https://patentgrep.com/patent/US20200399732A1 ## CPC - C21D 9/46: for sheet metals - C21D 6/002: {containing Cr (C21D6/004 takes precedence)} - C21D 6/005: {containing Mn} - C21D 6/008: {containing Si} - C21D 8/1222: {Hot rolling} - C21D 8/1233: {Cold rolling} - C21D 8/1255: {with diffusion of elements, e.g. decarburising, nitriding} - C21D 8/1272: {Final recrystallisation annealing} - C21D 8/1283: {Application of a separating or insulating coating} - C22C 38/001: {containing N} - C22C 38/002: {containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60} - C22C 38/008: {containing tin} - C22C 38/02: containing silicon - C22C 38/04: containing manganese - C22C 38/06: containing aluminium - C22C 38/20: with copper - C22C 38/34: with more than 1.5% by weight of silicon - C22C 38/60: containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur - H01F 1/147: Alloys characterised by their composition {(treatment thereof for enhancing their electromagnetic properties C21D8/12)} - C21D 2201/05: Grain orientation - C22C 2202/02: Magnetic - C21D: MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass C23F17/00; unidirectional solidification of eutectic materials or unidirectional demixing of eutectoid materials C30B) - C22C: ALLOYS (treatment of alloys C21D, C22F) - H01F: MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES ## Abstract A grain-oriented electrical steel sheet includes: a silicon steel sheet including Si and Mn; a glass film arranged on a surface of the silicon steel sheet; and an insulation coating arranged on a surface of the glass film, wherein the glass film includes a Mn-containing oxide. ## Claims ### Claim at position 1 1-15. (canceled) ### Claim 16 A grain-oriented electrical steel sheet comprising: a silicon steel sheet including, as a chemical composition, by mass %, 2.50 to 4.0% of Si, 0.010 to 0.50% of Mn, 0 to 0.20% of C, 0 to 0.070% of acid-soluble Al, 0 to 0.020% of N, 0 to 0.080% of S, 0 to 0.020% of Bi, 0 to 0.50% of Sn, 0 to 0.50% of Cr, 0 to 1.0% of Cu, and a balance consisting of Fe and impurities; a glass film arranged on a surface of the silicon steel sheet; and an insulation coating arranged on a surface of the glass film, wherein the glass film includes a Mn-containing oxide. ### Claim 17 (depends on 16) The grain-oriented electrical steel sheet according to claim 16, wherein the Mn-containing oxide includes at least one comprising a Braunite and Mn3O4. ### Claim 18 (depends on 16) The grain-oriented electrical steel sheet according to claim 16, wherein the Mn-containing oxide is arranged at an interface with the silicon steel sheet in the glass film. ### Claim 19 (depends on 17) The grain-oriented electrical steel sheet according to claim 17, wherein the Mn-containing oxide is arranged at an interface with the silicon steel sheet in the glass film. ### Claim 20 (depends on 18) The grain-oriented electrical steel sheet according to claim 18, wherein 0.1 to 30 pieces/μm2 of the Mn-containing oxide are arranged at the interface in the glass film. ### Claim 21 (depends on 19) The grain-oriented electrical steel sheet according to claim 19, wherein 0.1 to 30 pieces/μm2 of the Mn-containing oxide are arranged at the interface in the glass film. ### Claim 22 (depends on 16) The grain-oriented electrical steel sheet according to claim 16, wherein when IFor is a diffracted intensity of a peak originated in a forsterite and ITiN is a diffracted intensity of a peak originated in a titanium nitride in a range of 41°<2θ<43° of an X-ray diffraction spectrum of the glass film measured by an X-ray diffraction method, the IFor and the ITiN satisfy ITiNins-S700-800. ### Claim 27 (depends on 26) The method for producing the grain-oriented electrical steel sheet according to claim 26, wherein, in the decarburization annealing process, the dec-P500-600 and the dec-P600-700 satisfy dec-P500-600>dec-P600-700. ### Claim 28 (depends on 26) The method for producing the grain-oriented electrical steel sheet according to claim 26, wherein, in the decarburization annealing process, a first annealing and a second annealing are conducted after raising the temperature of the cold rolled steel sheet, and wherein when a dec-TI is a holding temperature in units of ° C., a dec-tI is a holding time in units of second, and a dec-PI is an oxidation degree PH2O/PH2 of an atmosphere during the first annealing and when a dec-TII is a holding temperature in units of ° C., a dec-tII is a holding time in units of second, and a dec-PII is an oxidation degree PH2O/PH2 of an atmosphere during the second annealing, the dec-TI is 700 to 900° C., the dec-tI is 10 to 1000 seconds, the dec-PI is 0.10 to 1.0, the dec-TII is (dec-TI+50°) C. or more and 1000° C. or less, the dec-tII is 5 to 500 seconds, the dec-PII is 0.00001 to 0.10, and the dec-PI and the dec-PII satisfy dec-PI>dec-PII. ### Claim 29 (depends on 28) The method for producing the grain-oriented electrical steel sheet according to claim 28, wherein, in the decarburization annealing process, the dec-P500-600, the dec-P600-700, the dec-PI, and the dec-PII satisfy dec-P500-600>dec-P600-700dec-PII. ### Claim 30 (depends on 26) The method for producing the grain-oriented electrical steel sheet according to claim 26, wherein, in the insulation coating forming process, when an ins-P600-700 is an oxidation degree PH2O/PH2 of an atmosphere in the temperature range of 600 to 700° C. and an ins-P700-800 is an oxidation degree PH2O/PH2 of an atmosphere in the temperature range of 700 to 800° C. during raising the temperature of the final annealed sheet, the ins-P600-700 is 1.0 or more, the ins-P700-800 is 0.1 to 5.0, and the ins-P600-700 and the ins-P700-800 satisfy ins-P600-700>ins-P700-800. ### Claim 31 (depends on 26) The method for producing the grain-oriented electrical steel sheet according to claim 26, wherein, in the final annealing process, the annealing separator includes a Ti-compound of 0.5 to 10 mass % in metallic Ti equivalent. ### Claim 32 (depends on 26) The method for producing the grain-oriented electrical steel sheet according to claim 26, wherein the slab includes, as the chemical composition, by mass %, at least one comprising 0.01 to 0.20% of C, 0.01 to 0.070% of acid-soluble Al, 0.0001 to 0.020% of N, 0.005 to 0.080% of S, 0.001 to 0.020% of Bi, 0.005 to 0.50% of Sn, 0.01 to 0.50% of Cr, and 0.01 to 1.0% of Cu. ### Claim 33 A grain-oriented electrical steel sheet comprising: a silicon steel sheet including, as a chemical composition, by mass %, 2.50 to 4.0% of Si, 0.010 to 0.50% of Mn, 0 to 0.20% of C, 0 to 0.070% of acid-soluble Al, 0 to 0.020% of N, 0 to 0.080% of S, 0 to 0.020% of Bi, 0 to 0.50% of Sn, 0 to 0.50% of Cr, 0 to 1.0% of Cu, and a balance comprising Fe and impurities; a glass film arranged on a surface of the silicon steel sheet; and an insulation coating arranged on a surface of the glass film, wherein the glass film includes a Mn-containing oxide. ### Claim 34 (depends on 16) A method for producing the grain-oriented electrical steel sheet according to claim 16, the method comprising: a hot rolling process of heating a slab to a temperature range of 1200 to 1600° C. and then hot-rolling the slab to obtain a hot rolled steel sheet, the slab including, as the chemical composition, by mass %, 2.50 to 4.0% of Si, 0.010 to 0.50% of Mn, 0 to 0.20% of C, 0 to 0.070% of acid-soluble Al, 0 to 0.020% of N, 0 to 0.080% of S, 0 to 0.020% of Bi, 0 to 0.50% of Sn, 0 to 0.50% of Cr, 0 to 1.0% of Cu, and a balance comprising Fe and impurities; a hot band annealing process of annealing the hot rolled steel sheet to obtain a hot band annealed sheet; a cold rolling process of cold-rolling the hot band annealed sheet by cold-rolling once or by cold-rolling plural times with an intermediate annealing to obtain a cold rolled steel sheet; a decarburization annealing process of decarburization-annealing the cold rolled steel sheet to obtain a decarburization annealed sheet; a final annealing process of applying an annealing separator to the decarburization annealed sheet and then final-annealing the decarburization annealed sheet so as to form a glass film on a surface of the decarburization annealed sheet to obtain a final annealed sheet; and an insulation coating forming process of applying an insulation coating forming solution to the final annealed sheet and then heat-treating the final annealed sheet so as to form an insulation coating on a surface of the final annealed sheet, wherein, in the decarburization annealing process, when a dec-S500-600 is an average heating rate in units of ° C./second and a dec-P500-600 is an oxidation degree PH2O/PH2 of an atmosphere in a temperature range of 500 to 600° C. during raising a temperature of the cold rolled steel sheet and when a dec-S600-700 is an average heating rate in units of ° C./second and a dec-P600-700 is an oxidation degree PH2O/PH2 of an atmosphere in a temperature range of 600 to 700° C. during raising the temperature of the cold rolled steel sheet, the dec-S500-600 is 300 to 2000° C./second, the dec-S600-700 is 300 to 3000° C./second, the dec-S500-600 and the dec-S600-700 satisfy dec-S500-600ins-S700-800.