Grain-oriented electrical steel sheet and method of manufacturing grain-oriented electrical steel sheet

Description

66 Grain-oriented electrical steel sheet and method of manufacturing grain-oriented electrical steel sheet TECHNICAL FIELD

[001] The present invention relates to a grain-oriented electrical steel sheet and to a method of manufacturing a grain-oriented electrical steel sheet.

[002] Priority is claimed in Japanese Patent Application No. 2023-065018, filed on April 12, 2023, the contents of which are incorporated herein by reference. FUNDAMENTALS OF THE TECHNIQUE

[003] Grain-oriented electrical steel sheet is a soft magnetic material and is mainly used as a transformer core material. Therefore, grain-oriented electrical steel sheet must have magnetic characteristics such as high magnetization and low iron loss. Iron loss is a power loss due to thermal energy consumption that occurs when the iron core is excited by an AC magnetic field, and iron loss should be as low as possible from an energy saving perspective.

[004] Iron loss is represented by the sum of hysteresis loss depending on crystal orientation, purity and the like, and eddy current loss depending on sheet thickness, specific resistance, size of magnetic domains and the like. Therefore, to reduce iron loss, it is effective to reduce hysteresis loss and eddy current loss. As a method to reduce hysteresis loss, a method is known in which the crystal orientation is developed in the Goss orientation (orientation {110} <001> ), which excels in magnetic characteristics (the degree of orientation development is increased), to increase magnetic flux density. As a method to reduce loss by Petition 870250091606, dated 07 / 10 / 2025, page 88 / 153 / 66 eddy currents, a method is known in which the Si content is increased to improve electrical resistance, the thickness of the steel sheet is reduced and the magnetic domain is refined.

[005] In particular, in the method of reducing sheet thickness, cold rolling is frequently used. However, a thin-sheet-thickness grain-oriented electrical steel sheet presents the problem that good magnetic characteristics cannot be stably obtained. For example, the following techniques are described as a method to improve the magnetic characteristics of a thin-sheet-thickness grain-oriented electrical steel sheet.

[006] Patent Document 1 describes a method for manufacturing a grain-oriented electrical steel sheet in which cold rolling is performed twice with an intermediate annealing interposed between them. Specifically, Patent Document 1 describes that hot rolling is completed at 850°C or more, the resulting material is immediately cooled and wound at 600°C or less, and then a carbide-setting heat treatment, including heat equalization in a temperature range of 650 to 900°C for 2 to 10 seconds, is performed before the first cold rolling. As a result, even a thin sheet-oriented electrical steel sheet can stably achieve excellent magnetic flux density in the longitudinal direction of the coil.

[007] Patent Document 2 describes a method for manufacturing a grain-oriented electrical steel sheet, in which cold rolling is performed one or two or more times, with intermediate annealing interposed between them. Specifically, Patent Document 2 describes that a strip with a final cold-roll reduction of 89% or more and rolled to the final sheet thickness is heat-treated at a temperature of 700°C or more at a heating rate of 50°C / s or more. Petition 870250091606, dated 07 / 10 / 2025, page 89 / 153 / 66 immediately before decarburizing annealing to obtain excellent magnetic flux density and iron loss. List of Citations Patent Documents

[008] Patent Document 1: Japanese Patent Application No. Examined, First Publication No. H06-145799

[009] Patent Document 2: Japanese Patent Application No. Examined, First Publication No. H07-62438 SUMMARY OF THE INVENTION Technical Problem

[0010] However, in conventional techniques, the magnetic flux density can vary. Furthermore, when rapid heating is performed in the decarburization annealing step, the adhesion between the steel sheet and the insulating coating (hereinafter referred to as coating adhesion) may deteriorate.

[0011] One objective of the present description is to provide a grain-oriented electrical steel sheet, excellent in magnetic properties and coating adhesion, and a method of manufacturing the same. Solution to the Problem

[0012] The essence of the present description is as follows.

[0013] [1] In one embodiment of the present description, a grain-oriented electrical steel sheet includes: a base steel sheet; a primary coating formed on the base steel sheet; and a secondary coating formed on the primary coating, wherein the base steel sheet includes, as chemical composition, in terms of % by mass, 2.50 to 4.00% Si, 0.01 0.30% of Mn, 0.0001 to 0.0100% of N, Petition 870250091606, dated 07 / 10 / 2025, p. 90 / 153 / 66 0.0005 to 0.010% of C, 0.010% of Al sol., 0.010% in total of at least one selected from the group consisting of a group consisting of S and Se, 0.001 to 0.010%, Ti, 0.50% Ni, 0.50% Cu, 0.30% Sb, 0.30% Sn, 0.50% Cr, 0.05% P, 0.05% Mo, 0.05% Ta, 0.010% Nb, 0.50% V, 0.010% B, 0.0150% Bi, 0.0150% Te, and a remainder including Fe and impurities; The grain-oriented electrical steel sheet has a B8 magnetic flux density of 1.902 T or more. When measurement points for crystalline orientation by an X-ray diffraction method are arranged on a surface of the base steel sheet at a 6 mm pitch in each of the rolling directions and one direction orthogonal to the rolling direction, the measurement points whose orientation difference is {211} <011> Measurements within 15° are included at a percentage of 5% or less relative to the total measurement points, in a line analysis along the lamination direction by an electron probe microanalyzer, an oxygen intensity profile. Petition 870250091606, dated 07 / 10 / 2025, page 91 / 153 / 66 obtained on a primary coating surface periodically includes a region with reduced oxygen intensity, and Iomin is defined as a minimum oxygen intensity value in the region with reduced oxygen intensity, Iomax is defined as a maximum oxygen intensity value in a region other than that with reduced oxygen intensity, and a ratio of Iomin / Iomax is 0.85 or more and 0.96 or less.

[0014] [2] In the grain-oriented electrical steel sheet according to [1], the region with reduced oxygen intensity can be included in an L range of 5 to 30 mm.

[0015] [3] In the grain-oriented electrical steel sheet according to [1] or [2], the base steel sheet may include, as a chemical composition, in terms of % by mass, at least one selected from the group consisting of: 0.01 to 0.50% Ni, 0.01 to 0.50% Cu, 0.01 to 0.30% Sb, 0.01 to 0.30% Sn, 0.01 to 0.50% Cr, 0.01 to 0.05% P, 0.01 to 0.05% Mo, 0.01 0.05% Ta, 0.001 to 0.010% Nb, 0.01 to 0.50% V, 0.001 to 0.010% B, 0.0100% or less Bi, and 0.0100% or less Te.

[0016] [4] The grain-oriented electrical steel sheet according to any of [1] to [3] may have a sheet thickness of 0.15 to 0.23 mm. Petition 870250091606, dated 07 / 10 / 2025, page 92 / 153 / 66

[0017] [5] In the grain-oriented electrical steel sheet according to any of [1] to [4], the base steel sheet can have a sheet thickness of 0.14 to 0.22 mm.

[0018] [6] In one embodiment of the present description, a method of manufacturing a grain-oriented electrical steel sheet includes: a hot rolling step of heating a plate and hot rolling the heated plate to obtain a hot-rolled steel sheet, the plate including, in terms of % by mass, 2.50 to 4.00% Si, 0.01 to 0.30% Mn, 0.0030 to 0.0150% N, 0.010 to 0.100% C, 0.010 to 0.050% Al sol., 0.010 to 0.050% in total of at least one selected from the group consisting of S and Se, 0.001 to 0.010% Ti, 0 to 0.50% Ni, 0 to 0.50% Cu, 0 to 0.30% Sb, 0 to 0.30% Sn, 0 to 0.50% Cr, 0 to 0.05% P, 0 to 0.05% Mo, 0 to 0.05% Ta, 0 to 0.010% Nb, 0 to 0.50% V, 0 to 0.010% B, 0 to 0.0200% Bi, 0 to 0.0200% Te, and Petition 870250091606, dated 07 / 10 / 2025, p. 93 / 153 / 66 a remainder including Fe and impurities; Hot band annealing stage for annealing hot-rolled steel sheet; A cold rolling step of hot-rolled steel sheet after the hot strip annealing step to obtain a cold-rolled steel sheet; a decarburization annealing step on cold-rolled steel sheet to obtain a decarburization annealed steel sheet; A final annealing step involving the application of an annealing separator to the decarburized annealed steel sheet, followed by final annealing, to form a primary coating on a surface of the decarburized annealed steel sheet, thus obtaining a final annealed steel sheet; and an insulating coating formation step to form an insulating coating on a surface of the final annealed steel sheet, wherein a total reduction in rolling is 89% or more in the cold rolling step, the decarburized annealing step includes: A local heating process involving the partial heating of a surface of cold-rolled steel sheet by irradiation with a laser beam in an air atmosphere at a range of 5 to 30 mm in a direction that forms a 30 to 150° angle relative to a rolling direction; A temperature raising process to raise the temperature of cold-rolled steel sheet after local heating in a non-oxidizing atmosphere from a temperature range of 450°C or less to a temperature range of 750 to 950°C, which is a temperature for decarburizing annealing, at an average rate of Petition 870250091606, dated 07 / 10 / 2025, p.94 / 153 / 66 heating of 80°C / s or more and 2000°C / s or less; and a process of annealing heat equalization by decarburizing cold-rolled steel sheet after the temperature raising process to an oxygen potential Po satisfying equation (1) below, when, under laser beam irradiation conditions in the local heating process, the average laser beam intensity is defined as P, in terms of a unit of W, the diameter of the focused spot in the rolling direction is defined as Dl, in terms of a unit of mm, the diameter of the focused spot in a direction of width orthogonal to the rolling direction is defined as Dc, in terms of a unit of mm, an irradiation time is defined as t, in terms of a unit of seconds, and an instantaneous input energy represented by 4 / π x P / (DlxDc) xt is defined as Up, in terms of a unit of J / mm2, an equation (2) below is satisfied:. Po < 0.6 - 0.04Up (1) < Up < 5 (2).

[0019] [7] In the manufacturing method of a grain-oriented electrical steel sheet according to [6], the sheet may include, as chemical composition, in terms of % by mass, at least one selected from the group consisting of: 0.01 to 0.50% Ni, 0.01 to 0.50% Cu, 0.01 to 0.30% of Sb, 0.01 to 0.30% of Sn, Petition 870250091606, dated 07 / 10 / 2025, p. 95 / 153 / 66 0.01 to 0.50% Cr, 0.01 to 0.05% of P, 0.01 to 0.05% Mo, 0.01 0.05% Ta, 0.001 to 0.010% Nb, 0.01 to 0.50% of V, 0.001 to 0.010% of B, 0.0100% or less Bi, and 0.0100% or less Te. Advantageous Effects of the Invention

[0020] According to the present description, it is possible to provide a grain-oriented electrical steel sheet with excellent magnetic properties and coating adhesion, and a method for manufacturing the same. BRIEF DESCRIPTION OF THE DRAWING

[0021] [FIG 1] A view illustrating an example of a cold-rolled steel sheet in which heated linear parts are formed.

[0022] [FIG 2] A view illustrating the diameter of the focal spot and the scanning speed of a laser beam.

[0023] [FIG 3] A schematic diagram of an oxygen intensity profile measured by EPMA line analysis of the surface of a primary coating. DESCRIPTION OF MODALITIES <1. Study of Current Inventors>

[0024] Next, an embodiment of the present invention will be described. First, studies conducted by the present inventors will be described. The present inventors investigated why a grain-oriented electrical steel sheet deteriorates and varies in magnetic flux density. As a result, the deterioration of magnetic characteristics is caused by secondary recrystallized grains with a crystalline orientation of {211} <011> , Petition 870250091606, dated 07 / 10 / 2025, page 96 / 153 / 66, which is inferior in magnetic characteristics. Furthermore, it was found that the magnetic characteristics vary in the longitudinal direction of the coil, and the magnetic characteristics deteriorate noticeably, particularly in the final portion of the longitudinal direction of the coil.

[0025] It is unclear why the oriented grains {211} <011> They recrystallize secondarily in the final portion of the longitudinal direction of the coil, but the following is assumed.

[0026] The longitudinal end of the coil may be heated more than desired during hot rolling, and the surface layer of the steel sheet in such an excessively heated part is easily decarburized during hot rolling. When the surface layer of the steel sheet is decarburized, the austenite content during hot rolling decreases. As a result, the orientation {211} <011> , which is a stable lamination orientation of ferrite, is readily developed in the surface layer of steel sheet. The {211} orientation is assumed. <011> be inherited and further developed, even after cold rolling, and as a result, many secondary recrystallized grains with the {211} orientation. <011> (hereinafter also referred to as “secondary recrystallized grains {211} <011> ”) are formed.Presumably, particularly when a grain-oriented electrical steel sheet is manufactured at a high cold rolling rate, the orientation {211} <011> developed during hot rolling is easily inherited during cold rolling.

[0027] As described above, the secondary recrystallized grains {211} <011> cause the deterioration of magnetic characteristics. Therefore, the present inventors have extensively studied means to suppress the formation of secondary recrystallized grains {211} <011> .

[0028] First, the present inventors investigated what facilitates the secondary recrystallization of oriented grains {211} <011> and they assumed that this occurs partly because of Goss's orientation (orientation Petition 870250091606, dated 07 / 10 / 2025, page 97 / 153 / 66 {110} <001> ), which serves as a nucleus for secondary recrystallization, decreases. The reduction in Goss orientation is considered to facilitate the secondary recrystallization of oriented grains {211} <011> , especially when the grain-oriented electrical steel sheet is manufactured with high reduction cold rolling.

[0029] Therefore, a method for enriching Goss's orientation was examined.

[0030] As a method for enriching Goss orientation, a rapid heating technique during the temperature rise process of the decarburizing annealing step is conventionally known. However, for grain-oriented electrical steel sheets, oriented grains {211} <011> Substances with inferior magnetic characteristics may be secondarily recrystallized, so that good magnetic characteristics are not obtained or the magnetic characteristics vary.

[0031] From this context, the present inventors further advanced the rapid heat treatment technique in the decarburization annealing temperature rise process. As a result, the present inventors found that it is effective in suppressing secondary recrystallization of oriented grains {211} <011> , to achieve the combination of: precise control of the irradiation conditions of the local rapid heating treatment with a laser beam; and control of the oxygen potential in the decarburization annealing step according to the irradiation conditions of the laser beam.

[0032] In conventional heating methods, such as radiation heating, energizing heating, and induction heating, the temperature rise rate is increased in the annealing stage, thus enriching the oriented Goss grains, which serve as a secondary recrystallization nucleus. On the other hand Petition 870250091606, dated 07 / 10 / 2025, page 98 / 153 / 66 side, in such a conventional heating method, the number of grains oriented near the {111} <112> The process of increasing the temperature rise rate during the annealing step, which promotes the growth of oriented Goss grains, tends to decrease in the central part of the steel sheet towards the thickness. Therefore, there is a limitation in improving the magnetic characteristics by increasing the temperature rise rate in the annealing step. In particular, a thin, grain-oriented electrical steel sheet has a problem with the decreasing number of oriented Goss grains, which serve as a secondary recrystallization nucleus. However, when a conventional heating method is applied, the entire sheet thickness is heated, and a sufficient effect cannot be obtained for the reason described above.

[0033] On the other hand, in local rapid heating treatment with a laser beam, only the surface layer of the steel plate (in particular, 1 / 5 of the thickness) is heated rapidly. Consequently, the oriented Goss grains, which serve as a secondary recrystallization nucleus, can be enriched in the surface layer of the steel plate, and the reduction in the number of oriented grains near the {111} <112> It can be suppressed in the central part of the sheet thickness of the steel plate. Therefore, it is possible to promote the secondary recrystallization of oriented Goss grains, which are superior in magnetic properties.

[0034] However, the present inventors investigated the relationship between the laser beam irradiation conditions and each characteristic of the electrical steel sheet, and found that coating adhesion can deteriorate. After specific examination, it was found that the annealing conditions (in particular, heat equalization conditions) in the decarburization annealing step affect coating adhesion, and it was found that it is effective to control the laser beam irradiation conditions and the annealing conditions within an appropriate range to improve coating adhesion. Petition 870250091606, dated 07 / 10 / 2025, p. 99 / 153 / 66

[0035] It was found that the decrease in coating adhesion is due to the decrease in the forsterite (Mg2SiO4) coating as a primary coating in the irradiation part of the laser beam. It is unclear why the primary coating is decreased in the irradiation part of the laser beam. However, it is presumed that, in the irradiation part of the laser beam, the inner SiO2 oxide layer is difficult to form in the decarburization annealing step, and the amount of primary coating formed is locally decreased in the final annealing step, which is a subsequent step.

[0036] Therefore, the present inventors intensively studied the annealing conditions in the decarburizing annealing step in order to promote the formation of the internal SiO2 oxide layer in the irradiation portion of the laser beam. As a result, the present inventors verified that it is effective to suppress the oxygen potential in the heat equalization process in the decarburizing annealing step according to the laser beam irradiation conditions to promote the formation of the internal SiO2 oxide layer. Presumably, although the amount of oxygen adhesion is reduced throughout the steel sheet when the oxygen potential is reduced in the heat equalization process, the formation of the internal SiO2 oxide layer is promoted, instead of an iron-based oxide layer, in the irradiation portion of the laser beam.

[0037] Next, a grain-oriented electrical steel sheet according to an embodiment of the present invention made based on the above verifications and a method of manufacturing the same will be described in detail. <2. Manufacturing method for grain-oriented electrical steel sheet>

[0038] A method for manufacturing a grain-oriented electrical steel sheet according to an embodiment of the present description will be described below (method for manufacturing a grain-oriented electrical steel sheet). Petition 870250091606, dated 07 / 10 / 2025, pages 100 / 153 / 66 oriented according to the modality).

[0039] The manufacturing method for a grain-oriented electrical steel sheet according to the embodiment includes the following steps: (I) a hot rolling step of heating a plate with a predetermined chemical composition and hot rolling the heated plate to obtain a hot-rolled steel sheet; (II) a hot band annealing step for annealing hot-rolled steel sheet; (iii) a cold rolling step of the hot-rolled steel sheet after the hot strip annealing step to obtain a cold-rolled steel sheet; (IV) a decarburization annealing step of the cold-rolled steel sheet to obtain a decarburization annealed steel sheet; and (V) a final annealing step of the decarburization annealed steel sheet.

[0040] Each step will be described below. For steps or conditions that are not described, known steps and conditions may be applied. (Hot Rolling Stage)

[0041] In the hot rolling stage, a plate with the chemical composition described below is heated to 1280°C or more, and the heated plate is hot rolled to obtain a hot-rolled steel sheet.

[0042] When the heating temperature is below 1280°C, the inclusion formed in the plate cannot be dissolved, and inhibitors are not sufficiently formed in the hot rolling stage or in the hot band annealing stage described later. Thus, the heating temperature of the plate is 1280°C or more. The upper limit of the heating temperature of the plate is not limited, but when heated above 1450°C, the plate or similar melts and becomes hard in hot rolling. Petition 870250091606, dated 07 / 10 / 2025, p. 101 / 153 / 66 hot. Thus, the heating temperature of the plate is preferably 1450°C or lower.

[0043] The hot rolling conditions are not particularly limited and can be suitably defined based on the required characteristics. The sheet thickness of the hot-rolled steel sheet obtained by hot rolling is preferably, for example, in a range of 1.0 mm or more and 4.0 mm or less. [Chemical Composition of the Plate]

[0044] To obtain preferred magnetic characteristics as a grain-oriented electrical steel sheet, the chemical composition of the hot-rolled sheet is within the following range. In the following description, unless otherwise specified, the notation “%” represents “% by mass”. In a numerical value limiting range described below with “to” interposed, the lower limit and the upper limit are included in the range. A numerical value indicated as “less than” or “more than” is not included in the numerical range. C: 0.010 to 0.100%

[0045] Carbon (C) is an element that has an improving effect on magnetic flux density, but when the C content of the plate exceeds 0.100%, productivity in the decarburization annealing step decreases. Furthermore, when the C content of the plate is high and decarburization is insufficient, the steel undergoes phase transformation in secondary recrystallization annealing (i.e., final annealing), and secondary recrystallization does not proceed sufficiently, resulting in a favorable magnetic flux density and low iron loss not being achieved, or the magnetic characteristics deteriorating due to magnetic aging. Therefore, the C content of the plate should be 0.100% or less. The lower the C content, the better for productivity and reduction of iron loss. From the point of view of productivity and reduction of iron loss... Petition 870250091606, dated 07 / 10 / 2025, page 102 / 153 / 66 iron loss, the C content is preferably 0.090% or less, and more preferably 0.080% or less.

[0046] On the other hand, when the C content of the plate is less than 0.010%, the effect of improving magnetic flux density cannot be obtained. Therefore, the C content of the plate is 0.010% or less. The C content is preferably 0.040% or more and more preferably 0.060% or more. Si: 2.50 to 4.00%

[0047] Silicon (Si) is an extremely effective element for increasing the electrical resistance (specific strength) of steel to reduce eddy current loss, which constitutes a portion of iron loss. When the Si content of the plate is less than 2.50%, the inherent resistance is small and eddy current loss cannot be sufficiently reduced. Furthermore, as the steel undergoes a phase transformation in secondary recrystallization annealing, secondary recrystallization does not proceed sufficiently, and a favorable magnetic flux density and low iron loss cannot be obtained. Thus, the Si content of the plate is 2.50% or more. The Si content of the plate is preferably 2.70% or more, more preferably 2.80% or more.

[0048] On the other hand, when the Si content exceeds 4.00%, the steel plate becomes brittle and the passability of the plate in the manufacturing stage is noticeably deteriorated. Therefore, the Si content of the plate is 4.00% or less. The Si content of the plate is preferably 3.90% or less, more preferably 3.80% or less. Mn: 0.01 to 0.30%

[0049] Mn (manganese) is an important element that forms MnS, which is one of the main inhibitors. When the Mn content of the plaque is less than 0.01%, the absolute amount of MnS needed to cause secondary recrystallization is insufficient. Thus, the Mn content of the plaque is 0.01% or more. The Mn content is preferably 0.03% or more and more preferably Petition 870250091606, dated 07 / 10 / 2025, page 103 / 153 / 66 0.06% or more.

[0050] On the other hand, when the Mn content of the plate exceeds 0.30%, the steel undergoes a phase transformation in the secondary recrystallization annealing, the secondary recrystallization does not proceed sufficiently and a favorable magnetic flux density and low iron loss cannot be obtained.

[0051] Therefore, the Mn content of the plate is 0.30% or less. The Mn content is preferably 0.28% or less and more preferably 0.26% or less.

[0052] At least one selected from the group consisting of S and Se: 0.010 to 0.050%

[0053] Sulfur (S) and selenium (Se) are elements that react with Mn to form MnS and MnSe inhibitors. Since either MnS or MnSe is required to form the inhibitor, one or both S and Se may be present in the plate. When the total of one or two S and Se is less than 0.010%, a sufficient inhibitor is not formed. Therefore, the total of one or two S and Se is 0.010% or more. The total of one or two S and Se is preferably 0.020% or more. Conversely, when the total of one or two S and Se exceeds 0.050%, hot embrittlement occurs, and hot rolling becomes significantly difficult. Thus, the total of one or two S and Se is 0.050% or less. The sum of one or two of S and Se is preferably 0.040% or less, and more preferably 0.030% or less. Al Sol.: 0.010 to 0.050%

[0054] Al sol. (acid-soluble aluminum) is a constituent element of a major inhibitor among the compounds called inhibitors that influence secondary recrystallization in grain-oriented electrical steel sheet, and is an essential element from the point of view of the development of secondary recrystallization in the base steel sheet according to the embodiment. When the Al sol. content in the plate is less than 0.010%, the AlN that acts as Petition 870250091606, dated 07 / 10 / 2025, page 104 / 153 / 66: The inhibitor is not generated sufficiently, and secondary recrystallization becomes insufficient. Therefore, the Al sol. content is 0.010% or more. The amount of Al sol. is preferably 0.020% or more. On the other hand, when the amount of Al sol. exceeds 0.050%, the AlN that acts as an inhibitor is not generated sufficiently, and secondary recrystallization becomes insufficient. Thus, the amount of Al sol. is 0.050% or less. The amount of Al sol. is preferably 0.040% or less, and more preferably 0.030% or less. N: 0.0030 to 0.0150%

[0055] N (nitrogen) is an element that reacts with acid-soluble Al to form AlN, which acts as an inhibitor. To form sufficient AlN to act as an inhibitor, the N content is 0.0030% or more. The N content is preferably 0.0050% or more.

[0056] On the other hand, when the N content is greater than 0.0150%, bubbles (pores) are generated in the steel sheet during cold rolling, the strength of the steel sheet increases, and the passability of the sheet during manufacturing deteriorates. Therefore, the N content of the plate is 0.0150% or less. The N content is preferably 0.0130% or less, and more preferably 0.0100% or less. Ni: 0 to 0.50%

[0057] Ni (nickel) is an effective element for increasing electrical resistance and reducing iron loss. Ni is an effective element for controlling the metallographic structure of hot-rolled steel sheet to improve magnetic characteristics. Thus, Ni may be included. When such an effect is obtained, the Ni content is preferably 0.01% or more. The Ni content is more preferably 0.02% or more.

[0058] On the other hand, when the Ni content is greater than 0.50%, secondary recrystallization can become unstable. Thus, the Ni content is 0.50% or less. The Ni content is preferably 0.30% or less. Petition 870250091606, dated 07 / 10 / 2025, p. 105 / 153 / 66 Cu: 0 to 0.50%

[0059] Cu (copper) is an element that contributes to increasing the occupancy rate of the Goss orientation in the secondary recrystallization structure and contributes to an improvement in the adhesion of the glass coating. Thus, Cu may be contained. When such an effect is obtained, the Cu content is preferably 0.01% or more. The Cu content is more preferably 0.02% or more and even more preferably 0.03% or more.

[0060] On the other hand, when the Cu content exceeds 0.50%, the steel sheet becomes brittle during hot rolling. Therefore, the Cu content of the plate is 0.50% or less. The Cu content is preferably 0.30% or less, more preferably 0.10% or less. Sb: 0 to 0.30%

[0061] Sb (antimony) is an element that has the effect of improving magnetic characteristics. Thus, Sb may be contained. When Sb is contained, the content is preferably 0.01% or more, so that the Sb favorably exhibits the effect of improving magnetic characteristics. The Sb content is preferably 0.02% or more.

[0062] On the other hand, when the Sb content exceeds 0.30%, the adhesion of the glass coating is deteriorated. Therefore, the Sb content is 0.30% or less. The Sb content is preferably 0.20% or less. Sn: 0 to 0.30%

[0063] Tin (Sn) is an element that has the effect of improving magnetic characteristics. Thus, Sn may be included. When Sn is included, the Sn content is preferably 0.01% or more to favorably exhibit the effect of improving magnetic characteristics. The Sn content is preferably 0.02% or more, more preferably 0.03% or more, considering the magnetic characteristics and coating adhesion.

[0064] On the other hand, when the Sn content exceeds 0.30%, the glass coating deteriorates considerably, and it is not possible to obtain Petition 870250091606, dated 07 / 10 / 2025, page 106 / 153 / 66 sufficient voltage for refinement of the magnetic domain, which results in the deterioration of iron loss characteristics. Thus, the Sn content is 0.30% or less. The Sn content is preferably 0.20% or less and more preferably 0.15% or less. Cr: 0 to 0.50%

[0065] Cr (chromium), similarly to Sn and Cu described later, is an element that contributes to increasing the occupancy rate of the Goss orientation in the secondary recrystallization structure to improve magnetic characteristics, and contributes to improved adhesion of the glass coating. Thus, Cr may be included. To obtain the above effect, the Cr content is preferably 0.01% or more, more preferably 0.02% or more, and even more preferably 0.03% or more.

[0066] On the other hand, when the Cr content exceeds 0.50%, Cr oxide is formed and the magnetic characteristics are deteriorated. Thus, the Cr content is 0.50% or less. The Cr content is preferably 0.30% or less, more preferably 0.10% or less. P: 0 to 0.05%

[0067] P (phosphorus) is an element that reduces workability in rolling. When the P content is 0.05% or less, it is possible to suppress the excessive reduction in rolling workability and suppress fracture during manufacturing. From this point of view, the P content is 0.05% or less. The P content is preferably 0.04% or less.

[0068] The lower limit of P content is not limited and can include 0%, but P is also an element that has the effect of improving texture and enhancing magnetic characteristics. To obtain this effect, the P content can be 0.005% or more, or it can be 0.01% or more. Mo: 0 to 0.05%

[0069] Mo (molybdenum) is an element that has the effect of improving Petition 870250091606, dated 07 / 10 / 2025, page 107 / 153 / 66 regarding magnetic characteristics. Thus, Mo can be contained. When Mo is contained, the Mo content is preferably 0.01% or more to favorably exhibit the effect of improving magnetic characteristics. The Mo content is more preferably 0.02% or more and even more preferably 0.03% or more.

[0070] On the other hand, when the Mo content is more than 0.05%, the cold rolling characteristics may be deteriorated, leading to fracture. Therefore, the Mo content is 0.05% or less. The Mo content is preferably 0.04% or less. Ta: 0 to 0.05%

[0071] Ta (tantalum) is a useful element that binds to N or C to function as an inhibitor. When such an effect is obtained, the Ta content can be greater than 0.0000%, or it can be 0.0005% or more. On the other hand, when the Ta content is greater than 0.05%, the magnetic characteristics may be deteriorated. Therefore, the Ta content can be 0.05% or less. The Ta content is preferably 0.04% or less. Nb: 0 to 0.010%

[0072] Nb (niobium) has a stabilizing effect on secondary recrystallization. When this effect is obtained, the Nb content can be greater than 0.0000%, or it can be 0.0005% or more. On the other hand, when the Nb content is greater than 0.010%, secondary recrystallization can become unstable. Therefore, the Nb content can be 0.010% or less. The Nb content is preferably 0.0050% or less. V: 0 to 0.50%

[0073] V (vanadium) is an effective element that binds to N or C to function as an inhibitor. Thus, V may be contained. When such an effect is obtained, the V content is preferably 0.01% or more, and more preferably 0.02% or more.

[0074] On the other hand, when the V content exceeds 0.50%, the Petition 870250091606, dated 07 / 10 / 2025, p. 108 / 153 / 66 magnetic characteristics may be deteriorated. Therefore, the V content is 0.50% or less. The V content is preferably 0.30% or less and more preferably 0.20% or less. B: 0 to 0.0200%

[0075] B (boron) has a stabilizing effect on secondary recrystallization. When this effect is obtained, the B content can be greater than 0.0000%, or it can be 0.0005% or more. On the other hand, when the B content is greater than 0.0200%, secondary recrystallization can become unstable. Therefore, the B content can be 0.0200% or less. The Bi content is preferably 0.0100% or less and more preferably 0.0050% or less. Bi: 0 to 0.0200%

[0076] Bi (bismuth) has the effect of improving magnetic characteristics. Thus, Bi may be included. When such an effect is obtained, the Bi content may be greater than 0.0000%, or it may be 0.0005% or more. On the other hand, when the Bi content is greater than 0.0200%, the passability of the sheet during cold rolling may be deteriorated. Furthermore, when purification during final annealing is insufficient and Bi remains in excess, the magnetic characteristics may be negatively affected. Therefore, the Bi content may be 0.0200% or less. The Bi content is preferably 0.0150% or less and more preferably 0.0100% or less. Te: 0 to 0.0200%

[0077] Te (tellurium) has a secondary recrystallization stabilizing effect. When this effect is obtained, the Te content can be greater than 0.0000%, or it can be 0.0005% or more. When the Te content is greater than 0.0200%, fracture may occur during hot or cold rolling. Therefore, the Te content can be 0.0200% or less. The Te content is preferably 0.0150% or less and more preferably 0.0100% or less. Remaining: Iron and impurities Petition 870250091606, dated 07 / 10 / 2025, p. 109 / 153 / 66

[0078] The chemical composition of the plate used in the manufacturing method of a grain-oriented electrical steel sheet according to the embodiment may contain the elements described above, and the remainder may be Fe and impurities. Here, impurities are contaminated by ore or scrap as raw material, or by a manufacturing environment or similar when the base steel sheet is industrially manufactured. Impurities mean elements that may be included in such a content that the action of the grain-oriented electrical steel sheet according to the embodiment is not adversely affected. (Hot Band Annealing Stage)

[0079] The hot band annealing stage is an annealing stage of hot-rolled steel sheet manufactured through the hot rolling stage. By performing this annealing treatment, recrystallization occurs in the metallographic structure of the steel sheet, and favorable magnetic characteristics can be obtained.

[0080] In the hot band annealing stage of the embodiment, the hot-rolled steel sheet manufactured through the hot rolling stage can be annealed according to a known method. The method of heating the hot-rolled steel sheet at the time of annealing is not particularly limited, and a known heating method can be adopted. The annealing conditions are also not particularly limited, but, for example, the hot-rolled steel sheet can be annealed in a temperature range of 900 to 1200°C for 10 seconds to 5 minutes. (Cold Rolling Stage)

[0081] In the cold rolling stage, the hot-rolled steel sheet, after the hot strip annealing stage, is subjected to cold rolling, including a plurality of passes to obtain a cold-rolled steel sheet. Cold rolling can be carried out in a single pass. Petition 870250091606, dated 07 / 10 / 2025, page 110 / 153 / 66 times. Alternatively, before the final passage in the cold rolling stage, intermediate annealing may be performed at least once or two or more times by interrupting the cold rolling, i.e., cold rolling may be performed several times with intervening intermediate annealing(s).

[0082] When intermediate annealing is performed, the temperature is preferably maintained between 1000 and 1200°C for 5 to 180 seconds. The annealing atmosphere is not particularly restricted. The number of intermediate annealing cycles is preferably 3 or less, considering the manufacturing cost.

[0083] The total reduction in lamination is 89% or more in the cold rolling stage. When the total reduction in lamination is less than 89%, a suitable primary recrystallization texture cannot be obtained. Specifically, when the total reduction in lamination is less than 89%, the sharpness of the Goss orientation, which serves as a secondary recrystallization core, cannot be sufficiently obtained and therefore good magnetic characteristics may not be achieved. In the cold rolling stage, the total reduction in lamination is preferably 90% or more, more preferably 91% or more, and even more preferably 92% or more.

[0084] Before the cold rolling stage, the surface of the hot-rolled steel sheet may be pickled under known conditions. (Decarburization Annealing Stage)

[0085] In the decarburization annealing step, cold-rolled steel sheet is decarburized to obtain a decarburized annealed steel sheet. In decarburization annealing, the cold-rolled steel sheet is primarily recrystallized, and C, which negatively affects magnetic characteristics, is removed from the steel sheet. In Petition 870250091606, dated 07 / 10 / 2025, page 111 / 153 / 66 manufacturing method of a grain-oriented electrical steel sheet according to the embodiment, the steel sheet is heated locally before being heated to an annealing temperature.

[0086] In other words, the decarburization annealing step according to the method includes: (IV-1) a local heating process of partially heating the surface of cold-rolled steel sheet by irradiation with a laser beam in an air atmosphere at a range of 5 to 30 mm in a direction that forms 30 to 150° relative to the rolling direction; (IV-2) a temperature raising process for raising the temperature of cold-rolled steel sheet after the local heating process in a non-oxidizing atmosphere from a temperature range of 450°C or less to a temperature range of 750 to 950°C, which is a temperature for decarburizing annealing, at an average heating rate of 80°C / s or more; and (IV-3) a decarburizing annealing thermal equalization process of cold-rolled steel sheet after the temperature raising process to an oxygen potential PO satisfying the following equation (1). [Local Heating Process]

[0087] In the local heating process, the surface of the cold-rolled steel sheet is partially heated by irradiation with a laser beam in an air atmosphere at a range of 5 to 30 mm in a direction that forms 30 to 150° relative to the rolling direction.

[0088] More specifically, in the local heating process, the surface of the cold-rolled steel sheet is heated in an air atmosphere so that the heated part made with a laser beam extends in a direction that forms 30 to 150° relative to the rolling direction (in a direction of ±60° relative to the direction perpendicular to the rolling direction) and Petition 870250091606, dated 07 / 10 / 2025, page 112 / 153 / 66 becomes a plurality of lines positioned at intervals of 5 to 30 mm in the rolling direction. The cold-rolled steel sheet after local heating presents linearly heated parts, as shown in FIG. 1.

[0089] In the manufacturing method of an oriented grain electrical steel sheet according to the embodiment, the steel sheet is heated locally so that the oriented Goss grains are enriched in the heated parts. The arrangement of the regions enriched with oriented Goss grains may be formed by lines extending in a direction that crosses the rolling direction described above, and the lines are preferably repeated at a predetermined interval in the rolling direction.

[0090] The direction of extension of the linear heated part is less than 30° or greater than 150° in relation to the rolling direction.

[0091] When the extension direction is nearly parallel to the lamination direction (30° or more, or 150° or less), the secondarily recrystallized Goss grains have a large angle of deviation, thus sometimes decreasing the magnetic flux density, although the cause is unknown.

[0092] When the heated linear portion has a spacing greater than 30 mm, the oriented Goss grains, which serve as secondary recrystallization nuclei, cannot be sufficiently obtained, thus sometimes decreasing the magnetic flux density. On the other hand, when the heated linear portion has a spacing less than 5 mm, the number of oriented Goss grains is excessive, and the number of grains with coincident site lattice orientation that promote the growth of oriented Goss grains is reduced, thus decreasing the degree of development for the Goss orientation.

[0093] The interval between the linear heated parts can be substantially equal to each other, but it can be controlled so that each Petition 870250091606, dated 07 / 10 / 2025, p. 113 / 153 / 66 one of the adjacent linear heated parts may have different intervals, provided that it is within the range of the linear heated part described above. For example, when a coil-shaped steel sheet is annealed in the final annealing step, the curvature is small in the inner peripheral portion, in which the interval of the heated parts can be narrowed so that the oriented Goss grains, which serve as a secondary recrystallization core, are enriched and the secondary recrystallized grains become smaller.

[0094] The width of the linear heated portion is preferably from 0.2 to 1.0 mm. When the width is less than 0.2 mm, the heated portion is small and the enrichment effect of Goss-oriented grains is reduced. On the other hand, when the width is greater than 1.0 mm, the enrichment effect of Goss-oriented grains is obtained, but the number of grains with coincident site lattice orientation is reduced, and the deviation angle from the Goss orientation increases after secondary recrystallization.

[0095] The length of the heated linear portion is not limited, but the heated linear portion is preferably formed throughout the region in the width direction of the steel sheet, or throughout the region in the width direction excluding the edge portion.

[0096] In addition, for local heating (formation of a linear heated part), a laser beam is irradiated for heating because local heating can be achieved and the influence on the surroundings is small.

[0097] When heating is performed by laser beam irradiation, the laser beam is irradiated under conditions that satisfy the following equation (2), wherein the average intensity of the laser beam is defined as P (W), the diameter of the focal spot in the lamination direction is defined as Dl (mm), the diameter of the focal spot in the width direction is defined as Dc (mm), the irradiation time is defined as t (s) and the instantaneous input energy Petition 870250091606, dated 07 / 10 / 2025, page 114 / 153 / 66 represented by 4 / πxP / (DlxDc)xt is defined as Up (J / mm2).

[0098] The diameter of the focal spot Dl is the diameter of the focal spot illustrated in FIG. 2 in the rolling direction. The diameter of the focal spot Dc is the diameter of the focal spot illustrated in FIG. 2 in the width direction (in the direction orthogonal to the rolling direction). The passing steel sheet is irradiated with a laser beam for a predetermined time t. When irradiation is performed across the entire steel sheet in the width direction, a plurality of irradiation points can be arranged in series in the width direction. 0.5 < Up < 5 (2)

[0099] When the conditions satisfy equation (2), the length of the recrystallized secondary grains in the rolling direction can be reduced, and the difference in the degree of development with respect to the Goss orientation is reduced. When equation (2) is not satisfied, it is not possible to obtain a sufficient effect.

[00100] In this embodiment, the purpose of irradiating a laser beam is not magnetic domain control, but microstructure control, as described above. That is, in the temperature raising process of the decarburizing annealing step in this embodiment, only the surface layer of the steel sheet is heated locally, and grooves are not formed on the surface of the steel sheet as in general magnetic domain control. [Temperature increase process]

[00101] In the temperature raising process, the cold-rolled steel sheet, after the local heating process, is heated in a non-oxidizing atmosphere from a temperature range of 450 °C or less to a temperature range of 750 to 950 °C, which is a temperature for decarburizing annealing, at an average heating rate of 80 °C / s or more.

[00102] The temperature increase above promotes the generation of Petition 870250091606, dated 07 / 10 / 2025, page 115 / 153 / 66 oriented grain nuclei of GOSS. When the average heating rate in the temperature range is less than 80°C / s, the nuclei are generated insufficiently and the size of the secondary recrystallized grains increases. Furthermore, when local heating is performed to reduce the size of the secondary recrystallization grain in the rolling direction, sufficient secondary recrystallization nuclei are needed to completely cover the entire surface of the steel sheet with the GOSS orientation, which is favorable to the magnetic characteristics. Therefore, the average heating rate is preferably 160°C / s or more, and more preferably 240°C / s or more. The upper limit of the temperature rise rate is not limited and can be determined by the capacity of the installation. For example, the temperature rise rate is 2000°C / s or less.

[00103] When the atmosphere during the temperature increase is not a non-oxidizing atmosphere, a tight SiO2 coating is formed on the surface layer of the steel sheet, and a decarburization defect or a coating defect occurs after final annealing. In this embodiment, the non-oxidizing atmosphere is a nitrogen atmosphere or a mixed nitrogen / hydrogen atmosphere, and is an atmosphere with a dew point of -50°C or higher and 0°C or lower. The dew point is preferably -5°C or lower, or -10°C or lower, from the point of view of suppressing SiO2 generation on the surface layer of the steel sheet and favorably advancing decarburization. The dew point can be, for example, -40°C or higher from the point of view of favorably promoting internal oxidation, which is easily controlled by the process.

[00104] Annealing after raising the temperature to 750 to 950°C in the temperature raising process is not limited. For example, the degree of oxidation (PH2O / PH2) in the annealing atmosphere (atmosphere in the furnace) is 0.15 to 1.0, and the temperature range is maintained for 10 to 600 seconds. [Heat equalization process] Petition 870250091606, dated 07 / 10 / 2025, page 116 / 153 / 66

[00105] In the heat equalization process, the cold-rolled steel sheet, after the temperature raising process, is annealed by decarburization to an oxygen potential PO satisfying the following equation (1). Po < 0.6 - 0.04Up (1)

[00106] As described above, the internal SiO2 oxide layer is considered to be more difficult to form in the heat equalization process in the irradiated part of the laser beam than in the non-irradiated part, and therefore the amount of primary coating formed is reduced in the irradiated part of the laser beam in the final annealing step, which is a subsequent step, resulting in reduced coating adhesion.

[00107] Therefore, in the heat equalization process in the modality, the PO₂ oxygen potential is maintained at a low level in the heat equalization process, according to the laser beam irradiation conditions, specifically, “Up”, to promote the formation of the internal SiO₂ oxide layer in the heat equalization process. Specifically, annealing is performed with a PO₂ oxygen potential satisfying equation (1).

[00108] Through the decarburization annealing step described above, the oriented Goss grains, which serve as secondary recrystallization nuclei, are enriched only in the surface layer of the steel sheet by local rapid heating with a laser beam; secondary recrystallization of the oriented Goss grains, which are superior in magnetic characteristics, can be promoted; and the formation of the inner SiO2 oxide layer can be promoted throughout the steel sheet, including the part irradiated by the laser beam. In this way, it is possible to obtain excellent magnetic characteristics and excellent coating adhesion. (Final Annealing Stage)

[00109] In the final annealing stage, an annealing separator Petition 870250091606, dated 07 / 10 / 2025, page 117 / 153 / 66. A predetermined anneal separator is applied to one or both surfaces of the decarburized annealed steel sheet obtained in the decarburized annealing step, and then the final annealing is performed. The final annealing is usually carried out for a long time in a state where the steel sheet is wound into a coil shape. Thus, before the final annealing, an annealing separator is applied to the dried decarburized annealed steel sheet in order to prevent seizing between the inside and outside of the coil winding.

[00110] As an annealing separator to be applied, an annealing separator containing MgO as a major component (e.g., containing 80% or more in terms of weight fraction) is used. When using an annealing separator containing MgO as a major component, a glass coating can be formed on the surface of the base steel sheet. When MgO is not a major component, no primary coating (glass coating) is formed. This is because the primary coating is made of a compound of Mg2SiO4 or MgAl₂O₄, and the Mg required for the formation reaction is insufficient when MgO is not a major component.

[00111] Final annealing can be carried out, for example, under conditions in which the temperature is raised to 1150 to 1250°C in a gaseous atmosphere containing hydrogen and nitrogen, and annealing is carried out in the temperature range for 10 to 60 hours. <3. Grain Oriented Electrical Steel Sheet>

[00112] Next, the grain-oriented electrical steel sheet obtained by the manufacturing method above will be described. (3-1. Chemical composition of the base steel sheet)

[00113] First, the chemical composition of the base steel sheet of the grain-oriented electrical steel sheet will be described. In the following description, unless otherwise specified, the notation “%” represents “% in Petition 870250091606, dated 07 / 10 / 2025, page 118 / 153 / 66 mass” in relation to the total mass of the base steel plate. C: 0.0005 to 0.010%

[00114] Since C (carbon) is an element that negatively affects the magnetic characteristics of grain-oriented electrical steel sheet, the C content is preferably as low as possible. In this embodiment, the C content is 0.010% or less. It is industrially difficult for the C content to become completely 0%. Therefore, the lower limit of the C content is substantially about 0.0005%. Yes: 2.50 to 4.00%

[00115] Silicon (Si) is an extremely effective element for increasing the electrical resistance (specific strength) of steel to reduce eddy current loss, which constitutes a portion of iron loss. When the Si content is less than 2.50%, the inherent resistance is small and eddy current loss cannot be sufficiently reduced. Furthermore, since steel undergoes phase transformation during secondary recrystallization annealing, secondary recrystallization does not proceed sufficiently, and a favorable magnetic flux density and low iron loss cannot be obtained.

[00116] Therefore, the Si content is 2.50% or more. The Si content is preferably 2.70% or more, and more preferably 2.80% or more.

[00117] On the other hand, when the Si content exceeds 4.00%, the steel sheet becomes brittle and the sheet's passability during the manufacturing process is noticeably impaired. Therefore, the Si content is 4.00% or less. The Si content is preferably 3.90% or less, and more preferably 3.80% or less. Mn: 0.01 to 0.30%

[00118] Mn (manganese) is an important element that forms MnS, which is one of the main inhibitors. When the Mn content is less than 0.01%, the absolute amount of MnS required to cause secondary recrystallization Petition 870250091606, dated 07 / 10 / 2025, page 119 / 153 / 66 is insufficient. Therefore, the Mn content is 0.01% or more. The Mn content is preferably 0.03% or more and more preferably 0.06% or more.

[00119] On the other hand, when the Mn content exceeds 0.30%, the steel undergoes phase transformation in secondary recrystallization annealing, secondary recrystallization does not proceed sufficiently, and a favorable magnetic flux density and low iron loss cannot be obtained. Therefore, the Mn content is 0.30% or less. The Mn content is preferably 0.28% or less and more preferably 0.26% or less.

[00120] At least one selected from the group consisting of S and Se: 0 to 0.010%

[00121] S and Se are raw materials for MnS and MnSe as inhibitors, but their content in the base steel sheet is preferably as low as possible because S and Se are elements that negatively affect the magnetic characteristics of grain-oriented electrical steel sheet. In this embodiment, the total amount of S and Se is 0.010% or less. The total amount of S and Se can be 0%. The total amount of S and Se can be 0.0005% or more. Al Sol.: 0 to 0.010%

[00122] As described above, Al sol. is a raw material for AlN as an inhibitor, but its content in the base steel sheet is preferably as low as possible, since Al sol. is an element that negatively affects the magnetic characteristics of grain-oriented electrical steel sheet. In this embodiment, the amount of Al sol. is 0.010% or less. The amount of Al sol. can be 0%. The amount of Al sol. can be 0.0005% or more. N: 0.0001 to 0.0100%

[00123] As described above, N is a raw material for AlN as an inhibitor, but its content in the base steel sheet is preferably as low as possible because N is an element that affects Petition 870250091606, dated 07 / 10 / 2025, p. 120 / 153 / 66 negatively affects the magnetic characteristics of grain-oriented electrical steel sheet. In this embodiment, the N content is 0.0100% or less. It is industrially difficult for the N content to become completely 0%. Therefore, the lower limit of the N content is substantially about 0.0001%. Ni: 0 to 0.50%

[00124] Ni (nickel) is an effective element for increasing electrical resistance and reducing iron loss. Ni is an effective element for controlling the metallographic structure of hot-rolled steel sheet to improve magnetic characteristics. Thus, Ni may be included. When such an effect is obtained, the Ni content is preferably 0.01% or more. The Ni content is more preferably 0.02% or more.

[00125] On the other hand, when the Ni content is greater than 0.50%, secondary recrystallization can become unstable. Thus, the Ni content is 0.50% or less. The Ni content is preferably 0.30% or less. Cu: 0 to 0.50%

[00126] Cu (copper) is an element that contributes to increasing the occupancy rate of the Goss orientation in the secondary recrystallization structure and contributes to improved adhesion of the glass coating. Thus, Cu may be contained. When such an effect is obtained, the Cu content is preferably 0.01% or more. The Cu content is more preferably 0.02% or more and even more preferably 0.03% or more.

[00127] On the other hand, when the Cu content exceeds 0.50%, the steel sheet becomes brittle during hot rolling. Therefore, the Cu content of the plate is 0.50% or less. The Cu content is preferably 0.30% or less, more preferably 0.10% or less. Sb: 0 to 0.30%

[00128] Sb (antimony) is an element that has the effect of improving magnetic characteristics. Thus, Sb may be present. When Sb is present, the content is preferably 0.01% or more, so that the Sb exhibits Petition 870250091606, dated 07 / 10 / 2025, page 121 / 153 / 66 favorably the effect of improving magnetic characteristics. The Sb content is preferably 0.02% or more.

[00129] On the other hand, when the Sb content exceeds 0.30%, the adhesion of the glass coating is deteriorated. Therefore, the Sb content is 0.30% or less. The Sb content is preferably 0.20% or less. Sn: 0 to 0.30%

[00130] Tin (Sn) is an element that has the effect of improving magnetic characteristics. Thus, Sn may be included. When Sn is included, the Sn content is preferably 0.01% or more to favorably exhibit the effect of improving magnetic characteristics. The Sn content is preferably 0.02% or more, more preferably 0.03% or more, considering the magnetic characteristics and coating adhesion.

[00131] On the other hand, when the Sn content exceeds 0.30%, the glass coating deteriorates considerably, and it is not possible to obtain sufficient voltage for magnetic domain refinement, resulting in deterioration of iron loss characteristics. Thus, the Sn content is 0.30% or less. The Sn content is preferably 0.20% or less and more preferably 0.15% or less. Cr: 0 to 0.50%

[00132] Cr (chromium), similarly to Sn and Cu described later, is an element that contributes to increasing the occupancy rate of the Goss orientation in the secondary recrystallization structure to improve magnetic characteristics, and contributes to improved adhesion of the glass coating. Thus, Cr may be included. To obtain the above effect, the Cr content is preferably 0.01% or more, more preferably 0.02% or more, and even more preferably 0.03% or more.

[00133] On the other hand, when the Cr content exceeds 0.50%, Cr oxide is formed and the magnetic characteristics deteriorate. Thus, the Petition 870250091606, dated 07 / 10 / 2025, p. 122 / 153 / 66 Cr content is 0.50% or less. The Cr content is preferably 0.30% or less, more preferably 0.10% or less. P: 0 to 0.05%

[00134] P (phosphorus) is an element that reduces workability in rolling. When the P content is 0.05% or less, it is possible to suppress the excessive reduction in rolling workability and suppress fracture during manufacturing. From this point of view, the P content is 0.05% or less. The P content is preferably 0.04% or less.

[00135] The lower limit of P content is not limited and can include 0%, but P is also an element that has the effect of improving texture and enhancing magnetic characteristics. To obtain this effect, the P content can be 0.005% or more, or it can be 0.01% or more. Mo: 0 to 0.05%

[00136] Molybdenum (Mo) is an element that has the effect of improving magnetic characteristics. Thus, Mo may be included. When Mo is included, the Mo content is preferably 0.01% or more to favorably exhibit the effect of improving magnetic characteristics. The Mo content is more preferably 0.02% or more and even more preferably 0.03% or more.

[00137] On the other hand, when the Mo content is more than 0.05%, the cold rolling characteristics may be deteriorated, leading to fracture. Therefore, the Mo content is 0.05% or less. The Mo content is preferably 0.04% or less. Ta: 0 to 0.05%

[00138] Ta (tantalum) has a stabilizing effect on secondary recrystallization. When this effect is achieved, the Ta content can be greater than 0.0000%, or it can be 0.0005% or more. On the other hand, when the Ta content is greater than 0.05%, secondary recrystallization can become unstable. Therefore, the Ta content can be 0.05% or less. The Ta content is Petition 870250091606, dated 07 / 10 / 2025, p. 123 / 153 / 66 preferably 0.04% or less. Nb: 0 to 0.010%

[00139] Nb (niobium) has a stabilizing effect on secondary recrystallization. When this effect is obtained, the Nb content can be greater than 0.0000%, or it can be 0.0005% or more. On the other hand, when the Nb content is greater than 0.010%, secondary recrystallization can become unstable. Therefore, the Nb content can be 0.010% or less. The Nb content is preferably 0.0050% or less. V: 0 to 0.50%

[00140] V (vanadium) is an effective element that binds to N or C to function as an inhibitor. Thus, V may be contained. When such an effect is obtained, the V content is preferably 0.01% or more, and more preferably 0.02% or more.

[00141] On the other hand, when the V content exceeds 0.50%, the magnetic characteristics may be deteriorated. Therefore, the V content is 0.50% or less. The V content is preferably 0.30% or less and more preferably 0.20% or less. B: 0 to 0.0200%

[00142] B (boron) has a stabilizing effect on secondary recrystallization. When this effect is obtained, the B content can be greater than 0.0000%, or it can be 0.0005% or more. On the other hand, when the B content is greater than 0.0200%, secondary recrystallization can become unstable. Therefore, the B content can be 0.0200% or less. The Bi content is preferably 0.0100% or less and more preferably 0.0050% or less. Bi: 0 to 0.0200%

[00143] Bi (bismuth) has the effect of improving magnetic characteristics. Thus, Bi may be present. When such an effect is obtained, the Bi content may be greater than 0.0000%, or it may be 0.0005% or more. On the other hand, when the Bi content is greater than 0.0200%, the passability of the sheet Petition 870250091606, dated 07 / 10 / 2025, p. 124 / 153 / 66 during cold rolling may be deteriorated. Furthermore, when purification during final annealing is insufficient and Bi remains in excess, the magnetic characteristics may be negatively affected. Therefore, the Bi content may be 0.0200% or less. The Bi content is preferably 0.0150% or less and more preferably 0.0100% or less. Te: 0 to 0.0200%

[00144] Te (tellurium) has a secondary recrystallization stabilizing effect. When this effect is obtained, the Te content can be greater than 0.0000%, or it can be 0.0005% or more. When the Te content is greater than 0.0200%, fracture may occur during hot or cold rolling. Therefore, the Te content can be 0.0200% or less. The Te content is preferably 0.0150% or less and more preferably 0.0100% or less. Remaining: Iron and impurities

[00145] The chemical composition of the base steel sheet of the grain-oriented electrical steel sheet according to the embodiment may contain the elements described above, with the remainder being Fe and impurities. Here, the impurities are contaminated by ore or scrap as raw material, or by a manufacturing environment or similar when the base steel sheet is industrially manufactured. Impurities mean elements that may be included in such a content that the action of the grain-oriented electrical steel sheet according to the embodiment is not adversely affected.

[00146] The chemical composition of the steel plate and sheet described above can be measured by a general analytical method. For example, the steel components can be measured using inductively coupled plasma atomic emission spectrometry (ICP-AES). C and S can be measured by a combustion infrared absorption method, N can be measured by an inert gas fusion and thermal conductivity method, and O can be measured by a gas fusion method. Petition 870250091606, dated 07 / 10 / 2025, page 125 / 153 / 66 inert and non-dispersive infrared absorption. (3-2. Configuration and Characteristics of Grain Oriented Electrical Steel Sheet)

[00147] The configuration and characteristics of the grain-oriented electrical steel sheet will be described below, according to the modality. <Orientação cristalina>

[00148] In the decarburization annealing step, as described above, the grain-oriented electrical steel sheet according to the embodiment is subjected to a combination of: precise control of the irradiation conditions of the local rapid heating treatment with a laser beam; and control of the oxygen potential in the decarburization annealing step according to the irradiation conditions of the laser beam. As a result, the resulting grain-oriented electrical steel sheet is sufficiently suppressed in the secondary recrystallization of oriented grains {211} <011> and can promote the secondary recrystallization of Goss-oriented grains, which are superior in magnetic characteristics, and reduce the variation of magnetic characteristics.

[00149] Specifically, when the measurement points for crystalline orientation by an X-ray diffraction method are arranged on the surface of the base steel sheet at a 6 mm pitch in each of the rolling directions and in the direction orthogonal to the rolling direction, the measurement points whose orientation difference is {211} <011> Measurements within 15° are included at a percentage of 5% or less relative to the total measurement points. This can further improve the magnetic characteristics of the grain-oriented electrical steel sheet.

[00150] The method for measuring crystal orientation is as follows.

[00151] A 60 mm x 300 mm x sheet thickness sample is obtained from grain-oriented electrical steel sheet, and the crystalline orientation is measured by the Lauer method. In the Lauer measurement, the orientation data Petition 870250091606, dated 07 / 10 / 2025, page 126 / 153 / 66 are obtained from 171 measurement points in the central portion of the sheet, with a pitch of 6 mm in each rolling direction and in the direction orthogonal to the rolling direction. From the orientation data of all measurement points, the number of crystalline orientation data whose deviation angle is {211} <011> If the angle is within 15°, it is analyzed to calculate the ratio R at all measurement points (171 points). <Análise EPMA>

[00152] As described above, a correlation is considered to exist between coating adhesion in the irradiation portion of the laser beam and the amount of forsterite formation as a primary coating. Therefore, in the grain-oriented electrical steel sheet of this type, the amount of formation is defined by analysis data from an electron probe microanalyzer (EPMA).

[00153] Specifically, regarding the grain-oriented electrical steel sheet according to the modality, in a line analysis along the rolling direction by EPMA, the oxygen intensity profile obtained on the surface of the primary coating periodically includes a region with reduced oxygen intensity; and Iomin is defined as a minimum oxygen intensity value in the region with reduced oxygen intensity, Iomax is defined as a maximum oxygen intensity value in the region different from the region with reduced oxygen intensity, and the ratio of Iomin / Iomax is 0.85 or more and 0.96 or less.

[00154] FIG. 3 is a schematic diagram of an oxygen intensity profile measured by EPMA line analysis of the surface of a primary coating. As illustrated in FIG. 3, in the oxygen intensity profile of the primary coating surface in the rolling direction measured by EPMA, there is a region with reduced oxygen intensity in the irradiated part of the laser beam. This means that the amount of forsterite formation as a primary coating is reduced in the part of Petition 870250091606, dated 07 / 10 / 2025, page 127 / 153 / 66 laser beam irradiation. In this modality, as the laser beam is irradiated in an irradiation range L of 5 to 30 mm, the region with reduced oxygen intensity also appears in a range L of 5 to 30 mm.

[00155] In the grain-oriented electrical steel sheet according to the modality, the amount of oxygen intensity reduction is suppressed in the region that has a reduced oxygen intensity. Specifically, Iomin is defined as the minimum O intensity value in the region with reduced oxygen intensity, Iomax is defined as the oxygen intensity in the other region, and the ratio Iomin / Iomax is 0.85 or more. When Iomin / Iomax is less than 0.85, the coating adhesion is lower in the irradiated part of the laser beam. Therefore, Iomin / Iomax is 0.85 or more, and preferably 0.87 or more. The upper limit of Iomin / Iomax is not particularly limited and can theoretically be 1. However, the upper limit is about 0.96 when local heating is actually achieved by laser beam irradiation.To obtain such an oxygen intensity ratio, for example, the heat equalization process of the decarburization annealing step described above can be carried out under an oxygen potential of 0.6 - 0.04 or less.

[00156] The specific method for EPMA analysis is as follows.

[00157] First, a 50 mm square test specimen is obtained from the grain-oriented electrical steel sheet with a secondary coating. The secondary coating is then removed using an alkaline solution. For example, the grain-oriented electrical steel sheet with a secondary coating is immersed in an aqueous solution of sodium hydroxide: NaOH: 30 to 50% by mass + H2O: 50 to 70% by mass at 80 to 90°C for 5 to 10 minutes, washed with water and dried after immersion, thus removing the secondary coating from the grain-oriented electrical steel sheet.

[00158] Next, after the removal of the secondary coating, the surface of the primary coating is subjected to line analysis with a Petition 870250091606, dated 07 / 10 / 2025, pp. 128 / 153 / 66 An EPMA (manufactured by JEOL, JXA-8230) was used to obtain an oxygen intensity profile. Under EPMA analysis conditions, the acceleration voltage was 15.0 kV, the irradiation current was 100 nA, the beam shape was a 10 μm x 300 μm strip, and distance measurements were taken 3 mm in 10 μm increments in the rolling direction continuously 15 times (45 mm total), thus performing line analysis in the rolling direction. From the measurement data obtained for O₂ intensity in the rolling direction, every 10 sections were calculated for moving average. From the maximum intensity Iomax and the minimum intensity Iomin, the ratio Iomin / Iomax was calculated.

[00159] The distance for line analysis may be greater than the laser irradiation width to observe the region with reduced oxygen intensity. For example, when the laser irradiation width is 30 mm, the distance for line analysis is 30 mm or more. <Espessura de chapa>

[00160] Grain-oriented electrical steel sheet according to the embodiment preferably has a sheet thickness of 0.15 to 0.35 mm from the point of view of reducing iron loss. In particular, grain-oriented electrical steel sheet more preferably has a sheet thickness of 0.18 mm or less.

[00161] Furthermore, in the grain-oriented electrical steel sheet according to the embodiment, the base steel sheet preferably has a sheet thickness of 0.14 to 0.22 mm from the point of view of reducing iron loss. In particular, the base steel sheet more preferably has a sheet thickness of 0.17 mm or less. Examples

[00162] Examples of the present invention will be described below, but the conditions in the Examples are examples of conditions adopted to confirm the feasibility and an effect of the present invention, and the present invention is not limited to these examples of conditions. The present invention Petition 870250091606, dated 07 / 10 / 2025, p. 129 / 153 / 66 may adopt various conditions, provided that an objective of the present invention is achieved without departing from the essence of the present invention.

[00163] A plate was prepared containing, as a chemical composition, the components presented in Tables 1.1 to 1.4 and a remainder containing Fe and impurities. The plate was heated to 1340°C in a heating furnace. The heated plate was subjected to a hot rolling step to manufacture a hot-rolled steel plate with a plate thickness shown in Tables 3.1 to 3.4. Then, the hot-rolled steel plate was subjected to a hot band annealing step at a hot band annealing temperature of 900 to 1200°C for a holding time of 10 to 300 seconds. After hot band annealing, a cold rolling step was performed to manufacture a cold-rolled steel plate with plate thicknesses shown in Tables 3.1 and 3.2.

[00164] Next, the cold-rolled steel sheet obtained was locally heated with a laser beam in an air atmosphere, so that the heated part became a plurality of straight lines, each extending so that the angle formed against the rolling direction was an angle of inclination (degrees) shown in Tables 3.2 to 3.4, and arranged in the rolling direction at a pitch (span L) (mm) shown in Tables 3.1 to 3.2. The irradiation conditions are shown in Tables 3.1 and 3.2.

[00165] Next, regardless of whether laser beam heating was performed, the temperature was raised from the temperature range of 400°C or less to the temperature range of 750 to 900°C at an average temperature rise rate shown in Tables 3.3 to 3.4 under a mixed nitrogen / hydrogen gas (non-oxidizing atmosphere) with a dew point of -20°C.

[00166] After the temperature increase, decarburization annealing was performed by thermal equalization at 850°C for 120 seconds, where the oxygen potential PO in the annealing atmosphere was as follows Petition 870250091606, dated 07 / 10 / 2025, pp. 130 / 153 / 66 shown in Tables 3.3 to 3.4, thus obtaining a decarburized annealed steel plate.

[00167] An annealing separator (aqueous fluid paste) containing MgO as the main component was applied to the surface of the decarburized annealed steel sheet. Then, the decarburized annealed steel sheet coated with the annealing separator was rolled into a coil. The coil was finally annealed to manufacture a final annealed steel sheet. The final annealing temperature was 1100°C to 1200°C, and the final annealing temperature was maintained for a holding time of 5 to 30 hours.

[00168] The steel sheet after the final annealing stage was subjected to a secondary coating formation stage (insulating coating formation stage).

[00169] Specifically, a secondary coating forming agent (insulating coating agent) containing mainly colloidal silica and phosphate was applied to the surface of each final annealed steel sheet (in the glass coating), and then the final annealed steel sheet coated with the secondary coating forming agent was baked to form a secondary coating, such as a voltage insulating coating, on the primary coating. One grain-oriented electrical steel sheet of each test number was manufactured by the above manufacturing steps.

[00170] The chemical composition of the base steel sheet was measured using the following component analysis method.

[00171] First, the primary coating and the secondary coating were removed from the base steel sheet by the following method. Specifically, the grain-oriented electrical steel sheet formed with a secondary coating was immersed in an aqueous solution of sodium hydroxide NaOH: 30 to 50% by mass + H2O: 50 to 70% by mass at 80 to 90°C. Petition 870250091606, dated 07 / 10 / 2025, page 131 / 153 / 66 for 5 to 10 minutes and, after immersion, washed with water and dried. At this stage, the secondary coating was removed from the grain-oriented electrical steel sheet.

[00172] In addition, the grain-oriented electrical steel sheet from which the secondary coating had been removed and on which the primary coating remained was immersed in high-temperature hydrochloric acid to remove the primary coating. Specifically, the grain-oriented electrical steel sheet on which the primary coating remained was immersed in 30 to 40% by mass of hydrochloric acid at 80 to 90°C for 1 to 5 minutes and, after immersion, washed with water and dried. Through the above steps, the base steel sheet was obtained from which the secondary and primary coatings were removed.

[00173] The chemical composition of the base steel sheet of the grain-oriented electrical steel sheet of each Test Number was measured by the following method.

[00174] First, the primary coating and secondary coating of the grain-oriented electrical steel sheet were removed using the method described above to extract the base steel sheet. Using the base steel sheet, the chemical composition of the base steel sheet was analyzed based on the following measurement method.

[00175] The chemical composition of the obtained steel sheet was measured by a method in accordance with JIS G0321:2017. Specifically, shavings were obtained from the base steel sheet, and the shavings were dissolved in an acid to obtain a solution. The solution was then subjected to inductively coupled plasma atomic emission spectrometry (ICPAES) to perform elemental analysis of the chemical composition. The C and S contents were determined by a well-known high-frequency combustion method (combustion infrared absorption method). The N content was determined using a well-known gas fusion method. Petition 870250091606, dated 07 / 10 / 2025, pp. 132 / 153 / 66 inert and thermal conductivity. Specifically, the measurement was performed using a component analyzer (trade name: ICPS-8000) manufactured by Shimadzu Corporation.

[00176] As a result of the analysis, the base steel plate included, as its chemical composition, the components shown in Tables 2.1 to 2.4 and a remainder including Fe and impurities. In Tables 1.1 to 1.4 and in Tables 2.1 to 2.4, “0.00”, “0.000” and “0.0000” indicate that the quantity of the corresponding element was less than the detection limit. <Avaliação>

[00177] The grain-oriented electrical steel sheet obtained was subjected to the following measurements and evaluations. [Magnetic Characteristic Measurement]

[00178] A test piece was obtained from a coil of grain-oriented electrical steel sheet from each Test No. The test piece was obtained from 2 positions: in the outer peripheral portion, a position approximately 10 m from the outer peripheral portion of the final annealed coil; and in the central portion, a position at 50% of the entire length of the coil. The size of the test piece was 60 mm x 300 mm x sheet thickness. The test piece included the central portion of the sheet width of the grain-oriented electrical steel sheet. A single-sheet magnetic property test (SST test) was performed according to JIS C2556:2015, and the test piece was applied with a magnetic field of 800 A / m to determine the magnetic flux density B8(T). The obtained magnetic flux density B8 is shown in “Magnetic flux density B8 (T)” in Tables 1 to 3. A magnetic flux density B8 of 1.902 T or more was evaluated as excellent magnetic properties and considered acceptable. [Crystal Orientation Measurement]

[00179] After measuring the magnetic characteristics, a 60 mm x 300 mm x sheet thickness sample was subjected to measurement of Petition 870250091606, dated 07 / 10 / 2025, page 133 / 153 / 66 crystalline orientation by the Lauer method. In the Lauer measurement, orientation data were acquired in the central portion of the plate at 171 measurement points with a 6 mm pitch. From the orientation data of all measurement points, the number of crystalline orientation data whose deviation angle is {211} <011> The value within 15° was analyzed to calculate the R ratio at all measurement points (171 points). Here, samples whose magnetic flux density B8 was less than 1,700 T in the magnetic characteristics measurement were considered defective in secondary recrystallization and were not subjected to the crystal orientation measurement. [Evaluation of coating adhesion]

[00180] A test piece was obtained from the grain-oriented electrical steel sheet of each Test No. The test piece was obtained in 2 positions: in the outer peripheral portion, a position approximately 10 m from the outer peripheral portion of the final annealed coil; and in the central portion, a position at 50% of the entire length of the coil. The test piece had a length of 15 mm in the direction perpendicular to the rolling and a length of 60 mm in the rolling direction. The test piece was wound onto round bars of various diameters, and the minimum diameter at which coating peeling was not visually observed (hereinafter, referred to as the bend peeling diameter) was determined, thus evaluating the coating adhesion. The smaller the bend peeling diameter, the better the coating adhesion.A scaling diameter of 40 mm or more was deemed unacceptable, as the coating is highly likely to flake off when an iron core is manufactured. [EPMA Analysis (Primary Coating Assessment)]

[00181] A 50 mm square test specimen was obtained from the grain-oriented electrical steel sheet of each Test No. The secondary coating was removed by the method described above. After the coating was removed Petition 870250091606, dated 07 / 10 / 2025, page 134 / 153 / 66 secondary, the surface of the primary coating was subjected to line analysis with an EPMA (manufactured by JEOL, JXA-8230) to obtain an oxygen intensity profile. As EPMA analysis conditions, the acceleration voltage was 15.0 kV, the irradiation current was 100 nA, the beam shape was a 10 μm x 300 μm strip, and the distance measurement of 3 mm in a 10 μm step in the rolling direction was performed continuously 15 times, thus performing the line analysis in the rolling direction. From the measurement data obtained for oxygen intensity in the rolling direction, every 10 sections were calculated for moving average. Based on the maximum intensity Iomax and the minimum intensity Iomin, the ratio Iomin / Iomax was calculated. <Resultados da Avaliação>

[00182] The sheet thickness and composition of the grain-oriented electrical steel sheets were shown in Tables 2.1 to 2.2.

[00183] The results of the magnetic characteristic measurement, the crystal orientation measurement, and the coating adhesion assessment of the grain-oriented electrical steel sheet are shown in Tables 3.5 to 3.6. When the magnetic flux density B8 was less than 1,700 T, the crystal orientation measurement and the coating adhesion assessment were not performed, and therefore blank fields were used.

[00184] Tests 1 to 30 were appropriate under all conditions. Therefore, the magnetic flux density B8 was 1.902 T or more in the central portion and the outer peripheral portion of the coil, and the lower magnetic grain abundance ratio, {211} <011> , was 5% or less. Furthermore, since Iomin / Iomax was 0.85 to 0.96, the peel-off diameter per fold was 30 mm or less and good coating adhesion was exhibited.

[00185] Tests #31, 32, 51 and 52 were not appropriate in reducing lamination. In tests #31 and 51, in which the reduction in lamination was Petition 870250091606, dated 07 / 10 / 2025, page 135 / 153 / 66 less than 89%, at a rate of {211} <011> was low, but the B8 magnetic flux density was low. Presumably, this is because the amount of Goss orientation was large, but the deviation angle was large due to the low lamination reduction. On the other hand, in tests #32 and #52, in which the lamination reduction was 94% or more, the ratio of {211} <011> was high and the magnetic flux density B8 was low. It is considered that, since the reduction in lamination was high, {211} <011> It was developed during cold rolling, and secondary recrystallization occurred easily.

[00186] Tests #33, 34, 53 and 54 were not heated with a laser beam. Tests #33 and 53 showed a low temperature rise rate in the decarburizing annealing step as a subsequent step, and were notably low in magnetic flux density B8. Tests #34 and 54 showed a high temperature rise rate in the decarburizing annealing step as a subsequent step, but showed a high ratio {211} <011> and therefore were lower in magnetic flux density B8. It is considered that, since laser beam heating was not performed, the Goss orientation was not sufficiently obtained and {211} <011> It was secondarily recrystallized.

[00187] Tests #35, 36, 55 and 56 were heated with a laser beam, but showed inadequate Up. Tests #35 and 55, whose Up was 0 or less, were insufficiently heated with a laser beam and therefore the amount of {211} <011> was large and the magnetic flux density B8 was low. Tests #36 and #56, whose Up was 6 or more, were excessively heated with a laser beam and therefore the amount of {211} <011> It was small, but the magnetic flux density was low. Presumably, this is because the precipitates in the irradiating part of the laser beam were thickened by overheating, and secondary recrystallization of the Goss orientation grains of the irradiating part of the laser beam occurred without orientation selectivity. Petition 870250091606, dated 07 / 10 / 2025, pp. 136 / 153 / 66

[00188] Tests #37, 38, 57 and 58 were heated with a laser beam, but the irradiation range was inadequate. Therefore, the magnetic flux density B8 was low. The abundance ratio of the crystalline orientation whose deviation angle is {211} <011> It was within 15°, which was also 5% or more. Presumably, this occurs because the enrichment effect of the Goss-oriented grains by a laser beam was insufficient.

[00189] Tests #39, 40, 59 and 60 were heated with a laser beam, but the angle of the irradiation portion was inadequate. Although the amount of {211} <011> If it were small, the magnetic flux density B8 would be low.

[00190] Although the reason is unknown, it is considered that when the inclination of the irradiation part is inadequate, secondary recrystallization of Goss-oriented grains with large deviation also frequently occurs, as well as secondary recrystallization of {211} <011> It is suppressed, but the oriented Goss grains lose orientation selectivity.

[00191] Tests No. 41, 42, 61 and 62 showed an inadequate temperature rise rate in the ACL temperature rise process. When the temperature rise rate was less than 80°C / s, the enrichment effect of the Goss-oriented grains appeared insufficient even when a laser beam was applied, and the amount of {211} <011> The temperature rise rate was high, and the B8 magnetic flux density was low. When the temperature rise rate was greater than 2000°C / s, the number of grains with coincident site lattice orientation was reduced, and therefore, the number of Goss-oriented grains was reduced in selective growth, resulting in a low B8 magnetic flux density.

[00192] As tests #43 to #50 and #63 to #70 showed an inadequate oxygen potential Po in the ACL thermal equalization process, the magnetic characteristics were good, but the coating adhesion deteriorated. When Po was less than 0.3, Iomin / IomaX was 0.97 or more. Petition 870250091606, dated 07 / 10 / 2025, page 137 / 153 / 66 It is considered that oxidation was insufficient in the decarburization annealing step and the primary coating was insufficiently formed during the final annealing, thus deteriorating the coating adhesion. When Po exceeded 0.6 - 0.04 Up, Iomin / Iomax was less than 0.85, and the coating adhesion was lower near the irradiation area of ​​the laser beam. Table 1.1 Steel Chemical composition of the plate (% by mass, remainder: Fe and impurities) No. Si Mn NC Al sol. S If S + Se Ti Ni Cu 0.020 0.002 0.00 0.00 3 3.45 0.08 0.0065 0.089 0.010 0.014 0.000 0.014 0.002 0.00 0.00 4 3.28 0.08 0.0150 0.066 0.034 0.018 0.000 0.018 0.003 0.00 0.00 5 3.16 0.14 0.0094 0.085 0.050 0.016 0.004 0.020 0.002 0.00 0.00 6 3.15 0.10 0.0083 0.092 0.026 0.020 0.000 0.020 0.001 0.00 0.00 7 3.25 0.30 0.0075 0.074 0.028 0.028 0.000 0.028 0.008 0.00 0.00 8 3.64 0.18 0.0041 0.066 0.032 0.018 0.012 0.030 0.001 0.00 0.00 9 2.95 0.12 0.0030 0.082 0.032 0.022 0.000 0.022 0.002 0.00 0.00 10 2.50 0.09 0.0055 0.015 0.032 0.050 0.000 0.050 0.002 0.00 0.00 11 3.45 0.10 0.0083 0.069 0.024 0.026 0.000 0.026 0.003 0.00 0.00 12 4.00 0.06 0.0099 0.021 0.018 0.034 0.012 0.046 0.002 0.00 0.00 13 3.45 0.04 0.0134 0.010 0.024 0.016 0.000 0.016 0.002 0.00 0.00 14 3.55 0.01 0.0082 0.083 0.012 0.020 0,000 0,020 0,002 0,00 0,00 15 3,42 0,05 0,0084 0,090 0,044 0,028 0,021 0,049 0,002 0,00 0,00 16 3,38 0,07 0,0065 0,061 0,048 0,018 0,000 0,018 0,001 0,00 0,00 17 3,29 0,08 0,0045 0,077 0,024 0,010 0,000 0,010 0,001 0,00 0,00 18 3,24 0,14 0,0056 0,083 0,026 0,042 0,000 0,042 0,003 0,00 0,00 19 3,26 0,10 0,0032 0,092 0,016 0,004 0,006 0,010 0,002 0,00 0,00 20 3,33 0,09 0,0078 0,034 0,032 0,026 0,000 0,026 0,002 0,03 0,07 21 3,21 0,08 0,0082 0,091 0,024 0,021 0,000 0,021 0,003 0,00 0,00 22 3,38 0,08 0,0079 0,076 0,025 0,024 0,000 0,024 0,004 0,02 0,02 23 3,45 0,09 0,0093 0,100 0,034 0,018 0,000 0,018 0,002 0,00 0,00 24 3,21 0,08 0,0121 0,038 0,036 0,016 0,000 0,016 0,004 0,00 0,13 25 3,18 0,13 0,0100 0,045 0,028 0,020 0,004 0,024 0,005 0,08 0,00 26 3,02 0,15 0,0087 0,084 0,021 0,028 0,000 0,028 0,002 0,00 0,09 27 3,22 0,04 0,0082 0,076 0,022 0,018 0,000 0,018 0,002 0,15 0,00 28 3,32 0,07 0,0082 0,078 0,024 0,022 0,000 0,022 0,002 0,00 0,09 29 3,39 0,09 0,0081 0,082 0,033 0,031 0,002 0.033 0.003 0.02 0.00 30 3.45 0.08 0.0084 0.088 0.031 0.022 0.000 0.022 0.003 0.00 0.00 Petition 870250091606, dated 07 / 10 / 2025, pp. 138 / 153 / 66 31 3.35 0.08 0.0079 0.073 0.025 0.024 0.000 0.024 0.003 0.00 0.00 32 3.40 0.08 0.0081 0.071 0.026 0.022 0.000 0.022 0.001 0.00 0.00 33 3.34 0.06 0.0040 0.085 0.048 0.012 0.000 0.012 0.001 0.00 0.00 34 3.26 0.04 0.0071 0.078 0.042 0.024 0.000 0.024 0.002 0.00 0.00 35 3.33 0.04 0.0072 0.085 0.024 0.031 0.000 0.031 0.002 0.00 0.00 36 3.33 0.08 0.0079 0.091 0.010 0.048 0.000 0.048 0.002 0.00 0.00 37 2.99 0.01 0.0094 0.099 0.031 0.023 0.002 0.025 0.002 0.00 0.00 38 3.40 0.05 0.0145 0.045 0.033 0.023 0.000 0.023 0.003 0.00 0.00 Table 1.2 Steel No. Chemical composition of the plate (% by mass, remainder: Fe and impurities) Si Mn NC Al sol. S Se S + Se Ti Ni Cu 39 3.21 0.07 0.0114 0.052 0.018 0.008 0.015 0.023 0.002 0.00 0.00 40 2.54 0.07 0.0082 0.042 0.022 0.018 0.000 0.018 0.002 0.00 0.00 41 3.45 0.08 0.0030 0.076 0.020 0.025 0.000 0.025 0.001 0.00 0.00 42 3.25 0.22 0.0064 0.089 0.020 0.018 0.012 0.030 0.002 0.00 0.00 43 3.21 0.06 0.0077 0.044 0.026 0.011 0.000 0.011 0.002 0.00 0.00 44 3.45 0.10 0.0079 0.076 0.024 0.022 0.000 0.022 0.002 0.00 0.00 45 3.29 0.04 0.0071 0.071 0.020 0.022 0.000 0.022 0.003 0.00 0.00 46 3.21 0.09 0.0042 0.071 0.031 0.018 0.000 0.018 0.002 0.00 0.00 47 3.25 0.14 0.0092 0.092 0.014 0.022 0.000 0.022 0.004 0.00 0.00 48 3.44 0.09 0.0101 0.062 0.022 0.029 0.000 0.029 0.002 0.00 0.00 49 3.43 0.10 0.0084 0.072 0.024 0.027 0.000 0.027 0.001 0.00 0.00 50 3.51 0.08 0.0090 0.023 0.029 0.032 0.000 0.032 0.002 0.00 0.00 51 3.25 0.07 0.0088 0.072 0.025 0.023 0.000 0.023 0.002 0.00 0.06 52 3.21 0.08 0.0083 0.069 0028 0,021 0,004 0,025 0,002 0,02 0,04 53 3,78 0,08 0,0081 0,078 0,012 0,011 0,000 0,011 0,002 0,00 0,00 54 3,23 0,18 0,0068 0,077 0,021 0,010 0,000 0,010 0,006 0,01 0,07 55 3,41 0,04 0,0121 0,023 0,025 0,019 0,005 0,024 0,004 0,00 0,00 56 3,44 0,06 0,0081 0,031 0,024 0,048 0,000 0,048 0,003 0,00 0,00 57 3,11 0,01 0,0086 0,066 0,033 0,031 0,000 0,031 0,006 0,04 0,00 58 2,82 0,09 0,0088 0,080 0,024 0,029 0,000 0,029 0,002 0,00 0,00 59 3,95 0,08 0,0092 0,090 0,029 0,030 0,014 0,044 0,001 0,01 0,00 60 2,55 0,08 0,0148 0,082 0,020 0,024 0,000 0,024 0,001 0,00 0,06 61 2,99 0,29 0,0100 0,071 0,029 0,021 0,000 0,021 0,002 0,00 0,00 62 3,25 0,21 0,0088 0,055 0,029 0,022 0,000 0,022 0,002 0,00 0,14 63 3,24 0,08 0,0082 0,043 0,024 0,024 0,000 0,024 0,001 0,02 0,05 64 3,33 0,07 0,0081 0,085 0,024 0,020 0,000 0,020 0,002 0,00 0,00 65 3,51 0,04 0,0077 0,065 0,027 0,032 0,000 0,032 0,002 0,04 0,04 66 3,51 0,11 0,0081 0,077 0,027 0,024 0,000 0,024 0,004 0,00 0,07, Petition 870250091606, dated 07 / 10 / 2025, pp. 139 / 153 / 66 67 3.45 0.16 0.0088 0.068 0.027 0.033 0.002 0.035 0.002 0.09 0.00 68 2.99 0.14 0.0109 0.077 0.021 0.018 0.000 0.018 0.001 0.02 0.00 69 3.20 0.12 0.0099 0.074 0.022 0.022 0.000 0.022 0.001 0.00 0.07 70 3.41 0.05 0.0079 0.088 0.019 0.048 0.000 0.048 0.002 0.00 0.00 71 3.24 0.08 0.0092 0.079 0.024 0.021 0.000 0.028 0.002 0.00 0.09 72 3.19 0.07 0.0084 0.076 0.025 0.022 0.000 0.018 0.003 0.15 0.07 73 3.35 0.08 0.0083 0.077 0.024 0.024 0.001 0.025 0.002 0.04 0.04 74 3.33 0.08 0.0079 0.076 0.024 0.022 0.000 0.011 0.002 0.00 0.00 75 3.42 0.08 0.0076 0.081 0.023 0.023 0.000 0.032 0.002 0.03 0.04 76 3.39 0.07 0.0079 0.069 0.026 0.024 0.000 0.024 0.003 0.00 0.07 Steel Chemical composition of the plate (% by mass, remainder: Fe and impurities) No. Sb Sn Cr P Mo Ta Nb VB Te Bi 1 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 4 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 5 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 6 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 7 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 8 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.0000 0.0000 9 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 10 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 11 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 12 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 13 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 14 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 15 0.00 0,00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 16 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 R$ 0.0000 17 0.000 0.0000 0.0000 19 0.01 0.00 0.00 0.00 0.00 0.01 0.000 0.00 0.000 0.0000 0.0200 20 0.00 0.10 0.07 0.00 0.000 0.01 0.000 0.0000 0.0000 21 0.02 0.00 0.00 0.01 0.00 0.00 0.000 0.00 0.001 0.0001 0.0000 22 0.00 0.08 . 0.02 0.00 0.000 0.04 0.002 0.0000 0.0020 23 0.01 0.00 0.00 0.00 0.00 0.00 0.001 0.00 0.000 0.0012 0.0000 24 0.00 0.12 0.14 0.01 0.01 0.00 0.001 0.00 0.000 0.0000 0.0005 25 0.00 0.00 0.00 0.04 0.00 0.03 0.000 0.00 0.000 0.0142 0.0000 26 0.00 0.24 0.03 0.00 0.02 0.00 0.000 0.00 0.000 0.0000 0.0035 Petition 870250091606, dated 07 / 10 / 2025, pp. 140 / 153 / 66 27 0.00 0.00 0.00 0.02 0.00 0.00 0.002 0.00 0.002 0.0000 0.0000 28 0.00 0.14 0.06 0.00 0.01 0.00 0.000 0.01 0.000 0.0000 0.0080 29 0.00 0.00 0.00 0.01 0.00 0.01 0.000 0.00 0.000 0.0000 0.0000 30 0.00 0.00 0.24 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 31 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 32 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 33 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 34 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 35 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 36 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 37 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 38 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 Table 1.4 Steel No. Chemical composition of the plate (% by mass, remainder: Fe and impurities) Sb Sn Cr P Mo Ta Nb VB Te Bi 39 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 41 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 42 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 43 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 44 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 45 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 46 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.0000 0.0000 47 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 48 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 49 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 50 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.000 0.0000 0.0000 51 0.01 0.08 0.00 0.02 0.01 0.00 0.001 0.00 0.000 0.0000 0.0005 52 0.00 0.00 0.00 0.04 0.00 0.03 0.000 0.00 0.000 0.0000 0,0011 53 0.00 0.00 0.00 0.00 0.00 0.04 0.002 0.00 0.001 0.0000 0.0000 54 0.00 0.21 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0087 0.0000 55 0.08 0.00 0.00 0.01 0.01 0.00 0.000 0.05 0.000 0.0000 0.0022 56 0.00 0.00 0.02 0.00 0.02 0.00 0.001 0.00 0.001 0.0000 0.0000 57 0.00 0.11 0.00 0.02 0.00 0.00 0.000 0.00 0.000 0.0014 0.0010 58 0.00 0.00 0.00 . 0.00 0.01 0.000 0.01 0.000 0.0000 0.0000 59 0.01 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.002 0.0000 0.0000 60 0.00 . 0.05 0.00 0.00 0.00 0.001 0.00 0.000 0.0000 0.0000 61 0.03 0.00 0.00 0.00 0.04 0.00 0.000 0.14 0.000 0.0002 0.0000 62 0.00 0.00 0.00 0.02 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 Petition 870250091606, dated 07 / 10 / 2025, pp. 141 / 153 / 66 63 0.00 0.10 0.02 0.00 0.00 0.00 0.000 0.00 0.001 0.0001 0.0000 64 0.01 0.02 0.04 0.00 0.00 0.00 0.00 0.000 0.000 0.0000 0.0009 65 0.00 0.00 0.04 0.00 0.00 0.00 0.000 0.08 0.000 0.0000 0.0000 66 0.00 0.00 0.00 0.04 0.00 0.00 0.003 0.00 0.000 0.0000 0.0014 67 0.00 0.00 0.04 0.00 0.00 0.02 0.000 0.00 0.001 0.0000 0.0140 68 0.00 0.20 0.00 0.03 0.01 0.00 0.000 0.00 0.000 0.0000 0.0000 69 0.00 0.12 0.08 0.00 0.00 0.00 0.00 0.000 0.00 0.0000 0.0021 70 0.00 0.00 0.00 0.00 0.00 0.02 0.000 0.00 0.000 0.0000 0.0000 71 0.00 0.24 0.03 0.00 0.02 0.00 0.000 0.00 0.000 0.0000 0.0029 72 0.01 0.12 0.00 0.02 0.00 0.00 0.001 0.00 0.001 0.0005 0.0000 73 0.00 0.00 0.03 0.01 0.01 0.01 0.000 0.00 0.000 0.0000 0.0015 74 0.00 0.10 0.06 0.00 0.00 0.01 0.002 0.00 0.000 0.0000 0.0000 75 0.00 0.00 0.04 0.00 0.00 0.00 0.000 0.08 0.000 0.0000 0.0000 76 0.00 0.08 0.00 0.01 0.00 0.00 0.001 0.00 0.000 0.0000 0.0009 Table 2.1 Steel No. Sheet thickness of the product Chemical composition of grain-oriented electrical steel sheet (% by mass, remainder: Fe and impurities) [mm] Si Mn NC Al Sol. S Se S + Se Ti Ni Cu 1 0.18 3.23 0.05 0.0024 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 2 0.18 3.29 0.07 0.0018 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 3 0.18 3.44 0.08 0.0012 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 4 0.18 3.27 0.08 0.0042 0.002 0.000 0.000 0.000 0.000 0.003 0.00 0.00 5 0.18 3.15 0.14 0.0014 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 6 0.18 3.14 0.10 0.0010 0.001 0.000 0.000 0.000 0.000 0.001 0.00 0.00 7 0.18 3.23 0.30 0.0004 0.002 0.000 0.000 0.000 0.000 0.008 0.00 0.00 8 0.18 3.61 0.18 0.0008 0.002 0.000 0.000 0.000 0.000 0.001 0.00 0.00 9 0.18 2.93 0.12 0.0018 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 10 0.18 2.50 0.09 0.0024 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 11 0.18 3.42 0.10 0.0010 0.002 0.000 0.000 0.000 0.000 0.003 0.00 0.00 12 0.18 3.98 0.06 0.0011 0.001 0.001 0.001 0.000 0.001 0.002 0.00 0.00 13 0.18 3.43 0.04 0.0032 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 14 0.18 3.53 0.01 0.0014 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 15 0.18 3.39 0.05 0.0016 0.002 0.000 0.000 0.001 0.001 0.002 0.00 0.00 16 0.18 3.34 0.07 0.0004 0.002 0.000 0.000 0.000 0.000 0.001 0.00 0.00 17 0.18 3.25 0.08 0.0008 0.002 0.00 0.000 0.000 0.000 0.001 0.00 0.00 18 0.18 3.24 0.14 0.0002 0.002 0.001 0.000 0.000 0.000 0.003 0.00 0.00 19 0.18 R$ 0.10 0.0008 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 20 0.18 3.31 0.09 0.0016 0.002 0.000 0.000 0.000 0.000 0.002 0.03 0.07 21 0.18 3.19 0.08 0.0004 0.003 0.000 0.000 0.000 0.000 0.003 0.00 0.00 Petition 870250091606, dated 07 / 10 / 2025, pp. 142 / 153 / 66 22 0,18 3,35 0,08 0,0009 0,003 0,000 0,000 0,000 0,000 0,004 0,02 0,02 23 0,18 3,40 0,09 0,0014 0,002 0,000 0,000 0,000 0,000 0,002 0,00 0,00 24 0,18 3,20 0,08 0,0028 0,002 0,000 0,000 0,000 0,000 0,004 0,00 0,13 25 0,18 3,17 0,13 0,0014 0,002 0,000 0,000 0,000 0,000 0,005 0,08 0,00 26 0,18 3,00 0,15 0,0028 0,002 0,000 0,000 0,000 0,000 0,002 0,00 0,09 27 0,18 3,19 0,04 0,0010 0,001 0,000 0,000 0,000 0,000 0,002 0,15 0,00 28 0,18 3,18 0,07 0,0026 0,002 0,000 0,000 0,000 0,000 0,002 0,00 0,09 29 0,18 3,37 0,09 0,0025 0,002 0,000 0,000 0,000 0,000 0,003 0,02 0,00 30 0,18 3,42 0,08 0,0021 0,001 0,000 0,000 0,000 0,000 0,003 0,00 0,00 31 0,18 3,33 0,08 0,0014 0,000 0,000 0,000 0,000 0,000 0,003 0,00 0,00 32 0,18 3,39 0,08 0,0014 0,001 0,000 0,000 0,000 0,000 0,001 0,00 0,00 33 0,18 3,31 0,06 0,0010 0,001 0,000 0,000 0,000 0,000 0,001 0,00 0,00 34 0,18 3,24 0,04 0,0008 0,001 0,000 0,000 0,000 0,000 0,002 0,00 0,00 35 0,18 3,31 0,04 0,0019 0,001 0,000 0,000 0,000 0,000 0,002 0,00 0,00 36 0,18 3.32 0.08 0.0024 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 37 0.18 2.97 0.01 0.0014 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 38 0.18 3.38 0.05 0.0014 0.002 0.000 0.000 0.000 0.000 0.003 0.00 0.00 [Table 2.2] Steel No. Sheet thickness of the product Chemical composition of grain-oriented electrical steel sheet (% by mass, remainder: Fe and impurities) [mm] Si Mn NC Al Sol. S Se S + Se Ti Ni Cu 39 0.18 3.19 0.07 0.0031 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 40 0.18 2.51 0.07 0.0030 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 41 0.18 3.43 0.08 0.0024 0.001 0.000 0.000 0.000 0.000 0.001 0.00 0.00 42 0.18 3.21 0.22 0.0014 0.002 0.000 0.000 0.000 0.000 0.002 0.00 0.00 43 0.18 3.19 0.06 0.0011 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 44 0.18 3.43 0.10 0.0014 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 45 0.18 3.29 0.04 0.0021 0.002 0.000 0.000 0.000 0.000 0.003 0.00 0.00 46 0.18 3.21 0.09 0.0020 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 47 0.18 3.25 0.14 0.0024 0.002 0.000 0.000 0.000 0.000 0.004 0.00 0.00 48 0.18 3.43 0.09 0.0018 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 49 0.18 3.41 0.10 0.0014 0.001 0.000 0.000 0.000 0.000 0.001 0.00 0.00 50 0.18 3.51 0.08 0.0022 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.00 51 0.18 3.23 0.07 0.0012 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.06 52 0.18 R 0.002 0.00 0.00 54 0.18 3.18 0.18 0.0012 0.001 0.000 0.000 0.000 0.000 0.006 0.01 0.07 55 0.18 3.41 0.04 0.0014 0.001 0.000 0.000 0.000 0.000 0.004 0.00 0.00 56 0.18 3.42 0.06 0.0009 0.002 0.001 0.001 0.000 0.001 0.003 0.00 0.00 Petition 870250091606, dated 07 / 10 / 2025, pp. 143 / 153 / 66 57 0,18 3,09 0,01 0,0010 0,002 0,000 0,000 0,000 0,000 0,006 0,04 0,00 58 0,18 2,81 0,09 0,0009 0,002 0,000 0,000 0,000 0,000 0,002 0,00 0,00 59 0,18 3,95 0,08 0,0014 0,002 0,000 0,000 0,000 0,000 0,001 0,01 0,00 60 0,18 2,51 0,08 0,0012 0,001 0,000 0,000 0,000 0,000 0,001 0,00 0,06 61 0,18 2,97 0,29 0,0009 0,002 0,000 0,000 0,000 0,000 0,002 0,00 0,00 62 0,18 3,24 0,21 0,0004 0,001 0,000 0,000 0,000 0,000 0,002 0,00 0,14 63 0,18 3,21 0,08 0,0014 0,001 0,000 0,000 0,000 0,000 0,001 0,02 0,05 64 0,18 3,33 0,07 0,0022 0,001 0,000 0,000 0,000 0,000 0,002 0,00 0,00 65 0,18 3,50 0,04 0,0021 0,001 0,000 0,000 0,000 0,000 0,002 0,04 0,04 66 0,18 3,45 0,11 0,0018 0,001 0,000 0,000 0,000 0,000 0,004 0,00 0,07 67 0,18 3,40 0,16 0,0009 0,001 0,000 0,000 0,000 0,000 0,002 0,09 0,00 68 0,18 2,98 0,14 0,0021 0,001 0,000 0,000 0,000 0,000 0,001 0,02 0,00 69 0,18 3,18 0,12 0,0014 0,001 0,000 0,000 0,000 0,000 0,001 0,00 0,07 70 0,18 3,40 0,05 0,0015 0,001 0,000 0,000 0,000 0,000 0,002 0,00 0,00 71 0,20 3.21 0.08 0.0012 0.001 0.000 0.000 0.000 0.000 0.002 0.00 0.09 72 0.20 3.17 0.07 0.0019 0.001 0.001 0.000 0.000 0.000 0.003 0.11 0.07 73 0.20 3.32 0.08 0.0015 0.001 0.001 0.000 0.000 0.000 0.002 0.04 0.03 74 0.23 3.31 0.08 0.0014 0.001 0.001 0.000 0.000 0.000 0.002 0.00 0.00 75 0.23 3.41 0.08 0.0012 0.002 0.001 0.000 0.000 0.000 0.001 0.02 0.05 76 0.23 3.38 0.07 0.0013 0.001 0.000 0.000 0.000 0.000 0.003 0.00 0.08 [Table 2.31] Steel No. Chemical composition of grain-oriented electrical steel sheet (% by mass, remainder: Fe and impurities) Sb Sn Cr P Mo Ta Nb VB Bi Te 1 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 2 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 3 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 4 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.0000 0.0000 5 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 6 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 7 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 8 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 9 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 10 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 11 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 12 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 13 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 14 0.00 0.00 0.00 0.00 0.00 0.00 0,000 0.00 0.000 0.0000 0.0000 15 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 16 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000, Petition 870250091606, dated 07 / 10 / 2025, pp. 144 / 153 / 66 17 0,00 0,00 0,00 0,00 0,00 0,00 0,000 0,00 0,000 0,0000 0,0000 18 0,00 0,00 0,00 0,00 0,00 0,00 0,000 0,00 0,000 0,0000 0,0000 19 0,01 0,00 0,00 0,00 0,00 0,01 0,000 0,00 0,000 0,0000 0,0001 20 0,00 0,10 0,07 0,00 0,05 0,00 0,000 0,01 0,000 0,0000 0,0000 21 0,02 0,00 0,00 0,01 0,00 0,00 0,000 0,00 0,001 0,0000 0,0000 22 0,00 0,08 0,04 0,00 0,02 0,00 0,000 0,04 0,002 0,0000 0,0000 23 0,01 0,00 0,00 0,00 0,00 0,00 0,001 0,00 0,000 0,0000 0,0000 24 0,00 0,12 0,14 0,01 0,01 0,00 0,001 0,00 0,000 0,0000 0,0000 25 0,00 0,00 0,00 0,04 0,00 0,03 0,000 0,00 0,000 0,0002 0,0000 26 0,00 0,24 0,03 0,00 0,02 0,00 0,000 0,00 0,000 0,0000 0,0000 27 0,00 0,00 0,00 0,02 0,00 0,00 0,002 0,00 0,002 0,0000 0,0000 28 0,00 0,14 0,06 0,00 0,01 0,00 0,000 0,01 0,000 0,0000 0,0001 29 0,00 0,00 0,00 0,01 0,00 0,01 0,000 0,00 0,000 0,0000 0,0000 30 0,00 0,00 0,24 0,00 0,00 0,00 0,000 0,00 0,000 0,0000 0,0000 31 0,00 0,00 0,00 0,00 0,00 0,00 0,000 0,00 0,000 0,0000 0,0000 32 0,00 0,00 0,00 0,00 0,00 0,00 0,000 0,00 0.000 0.0000 0.0000 33 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 34 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 35 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 36 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 37 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 38 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000, [Table 2.4] Steel No. Chemical composition of grain-oriented electrical steel sheet (% by mass, remainder: Fe and impurities) Sb Sn Cr P Mo Ta Nb VB Bi Te 39 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 40 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 41 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.0000 0.0000 42 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.0000 0.0000 43 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 44 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 45 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 46 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 47 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 48 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 49 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 50 0.00 0.00 0.00 0.00 0.00 0.00 0.000 0.000 0.0000 0.0000 51 0.01 0.08 0.00 0.02 0.01 0.00 0.001 0.00 0.000 0.0000 0.0000 52 0.00 0.00 0.00 0.04 0.00 0,03 0,000 0,00 0,000 0,0000 0,0000, Petition 870250091606, dated 07 / 10 / 2025, pp. 145 / 153 / 66 53 0,00 0,00 0,00 0,00 0,00 0,04 0,002 0,00 0,001 0,0000 0,0000 54 0,00 0,21 0,00 0,00 0,00 0,00 0,000 0,00 0,000 0,0001 0,0000 55 0,08 0,00 0,00 0,01 0,01 0,00 0,000 0,05 0,000 0,0000 0,0000 56 0,00 0,00 0,02 0,00 0,02 0,00 0,001 0,00 0,001 0,0000 0,0000 57 0,00 0,11 0,00 0,02 0,00 0,00 0,000 0,00 0,000 0,0001 0,0000 58 0,00 0,00 0,00 0,00 0,00 0,01 0,000 0,01 0,000 0,0000 0,0000 59 0,01 0,00 0,00 0,02 0,00 0,00 0,000 0,00 0,002 0,0000 0,0000 60 0,00 0,00 0,05 0,00 0,00 0,00 0,001 0,00 0,000 0,0000 0,0000 61 0,03 0,00 0,00 0,00 0,04 0,00 0,000 0,14 0,000 0,0000 0,0000 62 0,00 0,00 0,00 0,02 0,00 0,00 0,000 0,00 0,000 0,0000 0,0000 63 0,00 0,10 0,02 0,00 0,00 0,00 0,000 0,00 0,001 0,0000 0,0000 64 0,01 0,02 0,04 0,00 0,00 0,00 0,000 0,00 0,000 0,0000 0,0000 65 0,00 0,00 0,04 0,00 0,00 0,00 0,000 0,08 0,000 0,0000 0,0000 66 0,00 0,00 0,00 0,04 0,00 0,00 0,003 0,00 0,000 0,0000 0,0000 67 0,00 0,00 0,04 0,00 0,00 0,02 0,000 0,00 0,001 0,0000 0,0001 68 0,00 0,20 0,00 0,03 0,01 0,00 0,000 0,00 0.000 0.0000 0.0000 69 0.00 0.12 0.08 0.00 0.00 0.00 0.000 0.00 0.000 0.0000 0.0000 70 0.00 0.00 0.00 0.00 0.00 0.02 0.000 0.00 0.000 0.0000 0.0000 71 0.00 0.22 0.03 0.00 0.02 0.00 0.00 0.00 0.000 0.0001 0.0000 72 0.01 0.11 0.00 0.02 0.00 0.00 0.001 0.00 0.001 0.0000 0.0000 73 0.00 0.00 0.03 0.01 0.01 0.01 0.000 0.00 0.000 0.0000 0.0000 74 0.00 0.10 0.04 0.00 0.00 0.01 0.001 0.00 0.000 0.0000 0.0000 75 0.00 0.00 0.04 0.00 0.00 0.00 0.000 0.08 0.000 0.0000 0.0000 76 0.00 0.06 0.00 0.01 0.00 0.00 0.001 0.00 0.000 0.0000 0.0000 Table 3.1 No. Cold band sheet thickness [mm] Hot band sheet thickness [mm] Cold rolling reduction (%) Laser irradiation Laser Up [J / mm2] Output (W) Dl [mm] Dc [mm] Irradiation time [s] Interval L [mm] Tilt angle [degrees] 1 0.17 2.3 93 Irradiated 1 5000 0.5 100 0.01 10 90 2 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 15 90 3 0.17 2.4 93 Irradiated 4 5000 0.5 100 0.03 15 80 4 0.17 2.0 92 Irradiated 5 5000 0.5 100 0.04 5 90 5 0.17 1.8 91 Irradiated 1 5000 0.5 100 0.01 5 30 6 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 10 90 7 0.17 2.3 93 Irradiated 4 5000 0.5 100 0.03 30 90 8 0.17 2.4 93 Irradiated 1 5000 0.5 100 0.01 10 90 9 0.17 1.6 89 Irradiated 3 5000 0.5 100 0.02 20 70 Petition 870250091606, dated 07 / 10 / 2025, pages 146 / 153 / 66 10 0.17 2.0 92 Irradiated 3 5000 0.5 100 0.02 15 90 11 0.17 2.2 92 Irradiated 5 5000 0.5 100 0.04 30 90 12 0.17 2.6 93 Irradiated 3 5000 0.5 100 0.02 10 90 13 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 5 90 14 0.17 2.3 93 Irradiated 1 5000 0.5 100 0.01 10 80 15 0.17 2.2 92 Irradiated 3 5000 0.5 100 0.02 5 90 16 0.17 1.6 89 Irradiated 1 5000 0.5 100 0.01 10 80 17 0.17 2.2 92 Irradiated 3 5000 0.5 100 0.02 10 90 18 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 10 90 19 0.17 2.4 93 Irradiated 1 5000 0.5 100 0.01 5 50 20 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 10 90 21 0.17 2.6 93 Irradiated 1 5000 0.5 100 0.01 15 90 22 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 15 90 23 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 10 70 24 0.17 2.0 92 Irradiated 5 5000 0.5 100 0.04 10 90 25 0.17 2.1 92 Irradiated 3 5000 0.5 100 0.02 10 70 26 0.17 2.3 93 Irradiated 5 5000 0.5 100 0.04 10 90 27 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 30 90 28 0.17 2.1 92 Irradiated 3 5000 0.5 100 0.02 10 90 29 0.17 2.6 93 Irradiated 3 5000 0.5 100 0.02 20 80 30 0.17 2.5 93 Irradiated 1 5000 0.5 100 0.01 10 80 31 0.17 1.4 88 Irradiated 3 5000 0.5 100 0.02 10 70 32 0.17 2.8 94 ​​Irradiated 5 5000 0.5 100 0.04 10 90 33 0.17 2.1 92 Not irradiated - - - - - - - 34 0.17 2.3 93 Not irradiated - - - - - - - 35 0.17 1.9 91 Irradiated 0 5000 0.5 100 0.00 10 90 36 0.17 2.2 92 Irradiated 6 5000 0.5 100 0.05 10 80 37 0.17 1.6 89 Irradiated 3 5000 0.5 100 0.02 40 90 38 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 40 90, Petition 870250091606, dated 07 / 10 / 2025, pages 147 / 153 / 66 [Table 3.2] No. Cold band sheet thickness [mm] Hot band sheet thickness [mm] Cold rolling reduction (%) Laser irradiation Laser Up [J / m m2] Output (W) Dl [mm] Dc [mm] Irradiation time [s] Interval L [mm] Tilt angle [degrees] 39 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 10 20 40 0.17 2.6 93 Irradiated 1 5000 0.5 100 0.01 10 20 41 0.17 2.3 93 Irradiated 1 5000 0.5 100 0.01 10 80 42 0.17 2.2 92 Irradiated 3 5000 0.5 100 0.02 10 90 43 0.17 2.1 92 Irradiated 1 5000 0.5 100 0.01 10 90 44 0.17 2.4 93 Irradiated 2 5000 0.5 100 0.02 10 90 45 0.17 2.2 92 Irradiated 3 5000 0.5 100 0.02 10 90 46 0.17 2.2 92 Irradiated 4 5000 0.5 100 0.03 10 90 47 0.17 2.3 93 Irradiated 5 5000 0.5 100 0.04 10 90 48 0.17 1.8 91 Irradiated 5 5000 0.5 100 0.04 10 90 49 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 10 90 50 0.17 2.4 93 Irradiated 1 5000 0.5 100 0.01 10 80 51 0.17 1.4 88 Irradiated 5 5000 0.5 100 0.04 10 90 52 0.17 2.8 94 ​​Irradiated 3 5000 0.5 100 0.02 30 90 53 0.17 2,6 93 Not irradiated - - - - - - - 54 0.17 2.2 92 Not irradiated - - - - - - - 55 0.17 2.5 93 Irradiated 0 5000 0.5 100 0.00 10 90 56 0.17 2.4 93 Irradiated 6 5000 0.5 100 0.05 10 80 57 0.17 1.9 91 Irradiated 3 5000 0.5 100 0.02 40 90 58 0.17 1.6 89 Irradiated 3 5000 0.5 100 0.02 40 90 59 0.17 2.4 93 Irradiated 3 5000 0.5 100 0.02 10 20 60 0.17 2.4 93 Irradiated 1 5000 0.5 100 0.01 10 20 61 0.17 1.8 91 Irradiated 1 5000 0.5 100 0.01 10 80 62 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 10 90 63 0.17 2.0 92 Irradiated 1 5000 0.5 100 0.01 10 90 64 0.17 2.2 92 Irradiated 2 5000 0.5 100 0.02 10 90 65 0.17 2.1 92 Irradiated 3 5000 0.5 100 0.02 10 90 66 0.17 2.4 93 Irradiated 4 5000 0.5 100 0.03 10 90 67 0.17 2.3 93 Irradiated 5 5000 0.5 100 0.04 10 90 68 0.17 2.6 93 Irradiated 5 5000 0.5 100 0.04 10 90 69 0.17 2.3 93 Irradiated 3 5000 0.5 100 0.02 10 90 70 0.17 2.5 93 Irradiated 1 5000 0.5 100 0.01 10 80, Petition 870250091606, dated 07 / 10 / 2025, pages 148 / 153 / 66 71 0.19 1.8 89 Irradiated 3 5000 0.5 100 0.02 10 90 72 0.19 2.3 92 Irradiated 3 5000 0.5 100 0.02 10 90 73 0.19 2.6 93 Irradiated 3 5000 0.5 100 0.02 10 90 74 0.22 2.0 89 Irradiated 3 5000 0.5 100 0.02 10 90 75 0.22 2.5 91 Irradiated 3 5000 0.5 100 0.02 10 90 76 0.22 3.0 93 Irradiated 3 5000 0.5 100 0.02 10 90 Table 3.3 No. Temperature rise rate of the decarburization annealing step V [°C / s] Oxygen potential of the decarburization annealing step heat equalization process Po Lower limit Upper limit Determination 1 80 0.42 0.30 0.55 O 2 80 0.45 0.30 0.50 O 3 100 0.32 0.30 0.45 O 4 100 0.33 0.30 0.40 O 5 200 0.50 0.30 0.55 O 6 200 0.30 0.30 0.50 O 7 400 0.44 0.30 0.45 O 8 400 0.44 0.30 0.55 O 9 800 0.45 0.30 0.50 O 10 800 0.44 0.30 0.50 O 11 1000 0.34 0.30 0.40 O 12 1000 0.32 0.30 0.50 O 13 1400 0.45 0.30 0.50 O 14 1400 0.45 0.30 0.55 O 15 1600 0.45 0.30 0.50 O 16 1600 0.45 0.30 0.55 O 17 2000 0.38 0.30 0.50 O 18 2000 0.32 0.30 0.50 O 19 80 0.49 0.30 0.55 O 20 80 0.33 0.30 0.50 O 21 100 0.44 0.30 0.55 O 22 100 0.42 0.30 0.50 O 23 400 0.45 0.30 0.50 O 24 400 0.33 0.30 0.40 O 25 1000 0.45 0.30 0.50 O 26 1000 0.33 0.30 0.40 O 27 1600 0.45 0.30 0.50 O 28 1600 0.42 0.30 0.50 O 29 2000 0.41 0.30 0.50 O Petition 870250091606, dated 07 / 10 / 2025, pages 149 / 153 / 66 30 2000 0.41 0.30 0.55 O 31 1000 0.42 0.30 0.50 O 32 1000 0.39 0.30 0.40 O 33 50 0.38 0.30 0.60 O 34 1000 0.31 0.30 0.60 O 35 150 0.48 0.30 0.60 O 36 1400 0.34 0.30 0.35 O 37 400 0.38 0.30 0.50 O 38 800 0.42 0.30 0.50 O [Table 3.4] No. Temperature rise rate of the decarburization annealing step V [°C / s] Oxygen potential of the decarburization annealing step heat equalization process Po Lower limit Upper limit Determination 39 800 0.45 0.30 0.50 O 40 1400 0.5 0.30 0.55 O 41 70 0.38 0.30 0.55 O 42 2100 0.42 0.30 0.50 O 43 400 0.6 0.30 0.55 Upper limit X 44 100 0.55 0.30 0.52 Upper limit X 45 800 0.52 0.30 0.50 Upper limit X 46 600 0.48 0.30 0.45 Upper limit X 47 100 0.42 0.30 0.40 Upper limit X 48 600 0.29 0.30 0.40 Lower limit X 49 800 0.24 0.30 0.50 Lower limit X 50 400 0.24 0.30 0.55 Lower limit X 51 1000 0.33 0.30 0.40 O 52 1600 0.45 0.30 0.50 O 53 50 0.38 0.30 0.60 O 54 1000 0.31 0.30 0.60 O 55 150 0.48 0.30 0.60 O 56 1400 0.32 0.30 0.35 O 57 400 0.38 0.30 0.50 O 58 800 0.42 0.30 0.50 O 59 800 0.45 0.30 0.50 O 60 1400 0.5 0.30 0.55 O 61 70 0.31 0.30 0.55 O 62 2100 0.38 0.30 0.50 O 63 400 0.57 0,30 0.55 Upper limit X 64 100 0.54 0.30 0.52 Upper limit X, Petition 870250091606, dated 07 / 10 / 2025, pages 150 / 153 / 66 65 800 0.53 0.30 0.50 Upper limit X 66 600 0.53 0.30 0.45 Upper limit X 67 100 0.45 0.30 0.40 Upper limit X 68 600 0.26 0.30 0.40 Lower limit X 69 800 0.24 0.30 0.50 Lower limit X 70 400 0.29 0.30 0.55 Lower limit X 71 400 0.30 0.30 0.50 72 100 0.45 0.30 0.50 73 1000 0.45 0.30 0.50 74 200 0.49 0.30 0.50 O 75 600 0.42 0.30 0.50 O 76 1600 0.45 0.30 0.50 O Table 3.5 No. Central portion of the coil (central portion) End portion of the coil (outer peripheral portion) Magnetic flux density B8 [T] Abundance ratio of {211}<011 > R [%] Peeling diameter per bend [mm] lomin / lomax Magnetic flux density B8 [T] Abundance ratio of {211}<011 > R [%] Peeling diameter per bend [mm] lomin / lomax Note 1 1.929 3 20 0.91 1.906 5 20 0.93 Example of invention 2 1.924 3 20 0.88 1.904 5 20 0.85 Example of invention 3 1.911 4 30 0.90 1.912 4 30 0.87 Example of invention 4 1.935 2 30 0.86 1.922 3 30 0.88 Example of invention 5 1.944 1 30 0.87 1.924 3 30 0.86 Example of invention 6 1.921 3 30 0.96 1.909 4 30 0.96 Example of invention 7 1.914 4 20 0.85 1.902 5 20 0.86 Example of invention 8 1.924 3 20 0.89 1.904 5 20 0.90 Example of invention 9 1.949 0 20 0.85 1.932 2 20 0.88 Example of invention 10 1.929 2 20 0.92 1.921 4 20 0.88 Example of invention 11 1.943 1 30 0.91 1.906 5 30 0.87 Example of invention 12 1.933 2 30 0.95 1,Example of invention 13 1.922 3 20 0.91 1.922 4 20 0.89 Example of invention 14 1.923 3 20 0.89 1.904 5 20 0.88 Example of invention 15 1.935 2 20 0.88 1.915 4 20 0.88 Example of invention 16 1.954 0 20 0.93 1.934 2 20 0.92 Example of invention 17 1.934 2 20 0.91 1.902 5 20 0.92 Example of invention 18 1.929 2 20 0.94 1.908 5 20 0.96 Example of invention 19 1.936 2 20 0.92 1.918 4 20 0.89 Example of invention, Petition 870250091606, dated 07 / 10 / 2025, pages 151 / 153 / 66 20 1.941 2 20 0.90 1.914 4 20 0.93 Example of invention 21 1.939 2 20 0.93 1.903 5 20 0.91 Example of invention 22 1.924 3 20 0.90 1.905 5 20 0.89 Example of invention 23 1.920 3 20 0.87 1.911 5 20 0.87 Example of invention 24 1.945 1 20 0.87 1.908 4 20 0.90 Example of invention 25 1.936 2 20 0.89 1.920 4 20 0.85 Example of invention 26 1.937 2 20 0.86 1.911 5 20 0.86 Example of invention 27 1.924 3 20 0.89 1.911 4 20 0.86 Example of invention 28 1.936 2 20 0.92 1.922 3 20 0.88 Example of invention 29 1.928 3 20 0.91 1.916 4 20 0.90 Example of invention 30 1.935 2 20 0.94 1.904 5 20 0.94 Example of invention 31 1.898 0 20 0.91 1.889 0 20 0.91 Comparative Example 32 1.770 13 20 0.85 1.765 15 20 0.88 Comparative Example 33 1.584 - - - 1.620 - - - Comparative Example 34 1.765 11 20 0.98 1.802 14 30 0.98 Comparative Example 35 1.842 11 20 0.97 1.765 15 20 0.97 Comparative Example 36 1.873 3 20 0.86 1.912 4 20 0.86 Comparative Example 37 1.802 12 20 0.90 1.801 13 20 0.93 Comparative Example 38 1,810 10 20 0.92 1.785 14 30 0.90 Comparative Example, Table 3.6 No. Central portion of the coil (central portion) End portion of the coil (outer peripheral portion) Magnetic flux density B8 [T] Abundance ratio of {211}<011 > R [%] Stripping diameter per bend [mm] lomin / lomax Magnetic flux density B8 [T] Abundance ratio of {211}<011 > R [%] Stripping diameter per bend [mm] lomin / lomax Note 39 1.894 3 20 0.86 1.867 5 30 0.85 Comparative Example 40 1.899 4 30 0.88 1.901 5 30 0.86 Comparative Example 41 1.687 - - - 1.555 - - - Comparative Example 42 1.901 3 30 0.88 1.903 4 20 0.90 Comparative Example 43 1.924 3 50 0.81 1.915 4 50 0.78 Comparative Example 44 1.921 3 50 0.80 1.904 4 40 0.83 Comparative Example 45 1.937 2 40 0.83 1.903 5 40 0.84 Comparative Example 46 1.926 3 40 0.83 1.912 4 40 0.83 Comparative Example 47 1.928 3 40 0.84 1.910 4 40 0.84 Comparative Example 48 1.935 2 40 0.99 1.911 4 50 0.98 Comparative Example 49 1.919 3 50 0.97 1.907 4 50 0.98 Comparative Example 50 1.908 4 50 0.98 1,905 5 50 0.98 Comparative Example, Petition 870250091606, dated 07 / 10 / 2025, pages 152 / 153 / 66 Example Comparative 51 1.899 0 20 0.86 1.901 0 20 0.88 Example Comparative 52 1.760 15 30 0.87 1.810 16 20 0.88 Example Comparative 53 1.551 - - - 1.528 - - - Example Comparative 54 1.793 13 20 0.98 1.769 14 30 0.97 Example Comparative 55 1.820 11 20 0.97 1.799 13 30 0.97 Example Comparative 56 1.891 3 20 0.85 1.908 5 30 0.88 Example Comparative 57 1.822 9 30 0.90 Example Comparative 58 1.821 12 30 0.90 1.766 15 30 0.92 Example Comparative 59 1.884 3 30 0.86 1.915 5 30 0.90 Example Comparative 60 1.886 4 20 0.88 1.926 4 20 0.89 Example Comparative 61 1.567 - - - 1.624 - - - Example Comparative 62 1.922 3 20 0.91 1.918 5 30 0.91 Example Comparative 63 1.934 2 40 0.84 1.903 5 40 0.84 Example Comparative 64 1.932 2 50 0.79 1.903 5 40 0.83 Example Comparative 65 1.926 3 50 0.81 1.916 4 40 0.84 Example Comparative 66 1.941 2 40 0.83 1.918 4 50 0.80 Example Comparative 67 1.943 2 40 0.84 1.910 4 40 0.84 Example Comparative 68 1.919 3 50 0.97 1.902 5 50 0.98 Example Comparative 69 1.924 3 50 0.98 1.904 5 40 0.98 Comparative Example 70 1.920 3 40 0.98 1.907 5 50 0.98 Comparative Example 71 1.949 0 20 0.96 1.945 1 20 0.96 Invention Example 72 1.932 2 20 0.88 1.923 3 20 0.88 Invention Example 73 1.922 3 30 0.87 1.911 4 20 0.88 Invention Example 74 1.958 0 20 0.85 1.950 1 20 0.84 Invention Example 75 1.945 1 30 0.88 1.926 3 30 0.90 Example of invention 76 1.928 3 20 0.88 1.911 4 20 0.88 Example of invention, INDUSTRIAL APPLICABILITY

[00193] According to the above embodiments of the present invention, it is possible to obtain a grain-oriented electrical steel sheet with excellent magnetic characteristics and coating adhesion. Therefore, the resulting grain-oriented electrical steel sheet can be suitably applied to the iron core material of a transformer and thus has high industrial applicability. Petition 870250091606, dated 07 / 10 / 2025, page 153 / 153

Claims

1 / 6 CLAIMS 1. Grain-oriented electrical steel sheet, characterized in that it comprises: a base steel sheet; a primary coating formed on the base steel sheet; and a secondary coating formed on the primary coating, wherein the base steel sheet includes, as chemical composition, in terms of % by mass, 2.50 to 4.00% Si, 0.01 to 0.30% Mn, 0.0001 to 0.0100% N, 0.0005 to 0.010% C, 0 to 0.010% Al sol., 0 to 0.010% in total of at least one selected from the group consisting of S and Se, 0.001 to 0.010% Ti, 0 to 0.50% Ni, 0 to 0.50% Cu, 0 to 0.30% Sb, 0 to 0.30% Sn, 0 to 0.50% Cr, 0 to 0.05% P, 0 to 0.05% Mo, 0 to 0.05% Ta, 0 to 0.010% Nb, 0 to 0.50% V, 0 to 0.010% B, 0 to 0.0100% Bi, 0 to 0.0100% Te, and a remainder including Fe and impurities, Petition 870250091606, dated 10 / 07 / 2025, p. 79 / 153 2 / 6 the grain-oriented electrical steel sheet has a magnetic flux density B8 of 1.902 T or more,When the measurement points for crystalline orientation by an X-ray diffraction method are arranged on a surface of the base steel sheet at a 6 mm spacing in each of the rolling directions and one direction orthogonal to the rolling direction, the measurement points whose orientation difference is {211} <011> Measurements within 15° are included at a percentage of 5% or less relative to the total measurement points. In a line analysis along the lamination direction using an electron probe microanalyzer, an oxygen intensity profile obtained on a primary coating surface periodically includes a region with reduced oxygen intensity. Iomin is defined as the minimum oxygen intensity value in the reduced oxygen intensity region, Iomax is defined as the maximum oxygen intensity value in a region other than the reduced oxygen intensity region, and the Iomin / Iomax ratio is 0.85 or higher and 0.96 or lower.

2. Grain-oriented electrical steel sheet according to claim 1, characterized in that the region with reduced oxygen intensity is included in an L interval of 5 to 30 mm.

3. Grain-oriented electrical steel sheet according to claim 1 or 2, characterized in that the base steel sheet includes, as its chemical composition, in terms of % by mass, at least one selected from the group consisting of: 0.01 to 0.50% Ni, 0.01 to 0.50% Cu, 0.01 to 0.30% Sb, 0.01 to 0.30% Sn, 0.01 to 0.50% Cr, Petition 870250091606, dated 07 / 10 / 2025, p. 80 / 153 3 / 6 0.01 to 0.05% P, 0.01 to 0.05% Mo, 0.01 to 0.05% Ta, 0.001 to 0.010% Nb, 0.01 to 0.50% V, 0.001 to 0.010% B, 0.0150% or less Bi, and 0.0150% or less Te.

4. Grain-oriented electrical steel sheet according to claim 1 or 2, characterized in that it has a sheet thickness of 0.15 to 0.23 mm.

5. Grain-oriented electrical steel sheet according to claim 1 or 2, characterized in that the base steel sheet has a sheet thickness of 0.14 to 0.22 mm.

6. Method for manufacturing a grain-oriented electrical steel sheet, characterized in that the method comprises: a hot rolling step of heating a plate and hot rolling the heated plate to obtain a hot-rolled steel sheet, the plate including, in terms of % by mass, 2.50 to 4.00% Si, 0.01 to 0.30% Mn, 0.0030 to 0.0150% N, 0.010 to 0.100% C, 0.010 to 0.050% Al sol., 0.010 to 0.050% in total of at least one selected from the group consisting of S and Se, 0.001 to 0.010% Ti, 0 to 0.50% Ni, 0 to 0.50% Cu, Petition 870250091606, of 10 / 07 / 2025, p. 81 / 153 4 / 6 0 to 0.30% Sb, 0 to 0.30% Sn, 0 to 0.50% Cr, 0 to 0.05% P, 0 to 0.05% Mo, 0 to 0.05% Ta, 0 to 0.010% Nb, 0 to 0.50% V, 0 to 0.010% B, 0 to 0.0200% Bi, 0 to 0.0200% Te,and a remainder including Fe and impurities; a hot band annealing step for annealing the hot-rolled steel sheet; a cold rolling step of the hot-rolled steel sheet after the hot band annealing step to obtain a cold-rolled steel sheet; a decarburization annealing step of the cold-rolled steel sheet to obtain a decarburization annealed steel sheet; a final annealing step of applying an annealing separator to the decarburization annealed steel sheet, followed by final annealing, to form a primary coating on a surface of the decarburization annealed steel sheet, thus obtaining a final annealed steel sheet; and an insulating coating formation step to form an insulating coating on a surface of the final annealed steel sheet, wherein a total reduction in rolling is 89% or more in the cold rolling step, Petition 870250091606, dated 07 / 10 / 2025, page 82 / 153 5 / 6The decarburization annealing step includes: a local heating process of partially heating a surface of the cold-rolled steel sheet by irradiation with a laser beam in an air atmosphere at a range of 5 to 30 mm in a direction forming 30 to 150° relative to a rolling direction; a temperature raising process to raise the temperature of the cold-rolled steel sheet after the local heating process in a non-oxidizing atmosphere from a temperature range of 450°C or less to a temperature range of 750 to 950°C, which is a temperature for decarburization annealing, at an average heating rate of 80°C / s or more and 2000°C / s or less; and a decarburization annealing heat equalization process of the cold-rolled steel sheet after the temperature raising process to an oxygen potential PO satisfying equation (1) below, when,Under laser beam irradiation conditions in the local heating process, the average laser beam intensity is defined as P, in terms of a unit of W, the diameter of the focal spot in the rolling direction is defined as Dl, in terms of a unit of mm, the diameter of the focal spot in a direction of width orthogonal to the rolling direction is defined as Dc, in terms of a unit of mm, an irradiation time is defined as t, in terms of a unit of seconds, and an instantaneous input energy represented by 4 / π x P / (Dl x Dc) x t is defined as Up, in terms of a unit of J / mm2, Petition 870250091606, 07 / 10 / 2025, p. 83 / 153 6 / 6 the following equation (2) is satisfied: Po < 0.6 - 0.04Up (1) 1 < Up < 5 (2)., 7. A method for manufacturing a grain-oriented electrical steel sheet according to claim 6, characterized in that the sheet includes, as its chemical composition, in terms of % by mass, at least one selected from the group consisting of: 0.01 to 0.50% Ni, 0.01 to 0.50% Cu, 0.01 to 0.30% Sb, 0.01 to 0.30% Sn, 0.01 to 0.50% Cr, 0.01 to 0.05% P, 0.01 to 0.05% Mo, 0.01 to 0.05% Ta, 0.001 to 0.010% Nb, 0.01 to 0.50% V, 0.001 to 0.010% B, 0.0100% or less Bi, and 0.0100% or less of Te. Petition 870250091606, dated 07 / 10 / 2025, p. 84 / 153

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