# US 2020/0399731 A1 · Non-oriented electrical steel sheet > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0399731 A1 - Document ID: US20200399731A1 - Status: Published application - Kind: A1 - Application number: 16/975,334 - Filed: 2019-03-20 - Published: 2020-12-24 - Earliest claimed: 2018-03-23 - Assignees: Nippon Steel Corporation - Applicants: Nippon Steel Corporation - Inventors: Takeru ICHIE; Masaru TAKAHASHI; Fuminobu MURAKAMI; Shinichi MATSUI; Masahiro YAMAMOTO - Web page: https://patentgrep.com/patent/US20200399731A1 ## CPC - C21D 9/46: for sheet metals - C21D 6/005: {containing Mn} - C21D 6/008: {containing Si} - C21D 8/00: Modifying the physical properties of ferrous metals or ferrous alloys by deformation combined with, or followed by, heat treatment (hardening articles or materials formed by forging or rolling with no further heating beyond that required for the formation C21D1/02) - C21D 8/1222: {Hot rolling} - C21D 8/1233: {Cold rolling} - C21D 8/1272: {Final recrystallisation annealing} - 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 38/004: {Very low carbon steels, i.e. having a carbon content of less than 0,01%} - C22C 38/005: {containing rare earths, i.e. Sc, Y, Lanthanides} - C22C 38/008: {containing tin} - C22C 38/02: containing silicon - C22C 38/04: containing manganese - C22C 38/06: containing aluminium - C22C 38/16: containing copper - C22C 38/60: containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur - H01F 1/14775: {in the form of sheets} - H01F 1/16: in the form of sheets (H01F1/147 takes precedence) - C21D 1/26: Methods of annealing - C21D 8/1261: {following hot rolling} - C21D 8/1283: {Application of a separating or insulating coating} - C22C 2202/02: Magnetic - Y02T 10/64: Electric machine technologies in electromobility - 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 - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A non-oriented electrical steel sheet includes a silicon steel sheet and an insulation coating. When t is a thickness of the silicon steel sheet and when PDR is defined as (PDR=(maximum−minimum)/minimum×100) which indicates a ratio concerned with maximum and minimum of number densities of AlN precipitates in three areas which are 1/10t area, ⅕t area, and ½t area from a surface of the silicon steel sheet along a thickness direction, the PDR is 50% or less. ## Claims ### Claim 1 A non-oriented electrical steel sheet comprising a silicon steel sheet and an insulation coating, wherein the silicon steel sheet includes, as a chemical composition, by mass %, 0.01 to 3.50% of Si, 0.0010 to 2.500% of Al, 0.01 to 3.00% of Mn, 0.0030% or less of C, 0.180% or less of P, 0.0030% or less of S, 0.0030% or less of N, 0.0020% or less of B, and a balance consisting of Fe and impurities, and when t is a thickness of the silicon steel sheet and when PDR is defined as a following (expression 1) which indicates a ratio concerned with maximum and minimum of number densities of AlN precipitates in three areas which are 1/10t area, ⅕t area, and ½t area from a surface of the silicon steel sheet along a thickness direction, the PDR is 50% or less, wherein the PDR=(the maximum−the minimum)÷the minimum×100 (expression 1). ### Claim 2 (depends on 1) The non-oriented electrical steel sheet according to claim 1, wherein the silicon steel sheet includes, as the chemical composition, by mass %, at least one selected from a group comprising 0.0500% or less of Sb, and 0.0100 to 0.2000% of Sn. ### Claim 3 (depends on 1) The non-oriented electrical steel sheet according to claim 1, wherein the silicon steel sheet includes, as the chemical composition, by mass %, at least one selected from a group comprising 0 to 1.00% of Cu, 0 to 0.0400% of REM, 0 to 0.0400% of Ca, and 0 to 0.0400% of Mg. ### Claim 4 (depends on 2) The non-oriented electrical steel sheet according to claim 2, wherein the silicon steel sheet includes, as the chemical composition, by mass %, at least one selected from a group comprising 0 to 1.00% of Cu, 0 to 0.0400% of REM, 0 to 0.0400% of Ca, and 0 to 0.0400% of Mg. ### Claim 5 A non-oriented electrical steel sheet comprising a silicon steel sheet and an insulation coating, wherein the silicon steel sheet includes, as a chemical composition, by mass %, 0.01 to 3.50% of Si, 0.0010 to 2.500% of Al, 0.01 to 3.00% of Mn, 0.0030% or less of C, 0.180% or less of P, 0.0030% or less of S, 0.0030% or less of N, 0.0020% or less of B, and a balance comprising Fe and impurities, and when t is a thickness of the silicon steel sheet and when PDR is defined as a following (expression 1) which indicates a ratio concerned with maximum and minimum of number densities of AlN precipitates in three areas which are 1/10t area, ⅕t area, and ½t area from a surface of the silicon steel sheet along a thickness direction, the PDR is 50% or less, wherein the PDR=(the maximum−the minimum)÷the minimum×100 (expression 1).