Non-oriented electrical steel sheet, rotor core, motor, and method for producing non-oriented electrical steel sheet

Description

Non-oriented electrical steel sheet, rotor core, motor, and method for producing non-oriented electrical steel sheet. TECHNICAL FIELD

[0001] The present invention relates to a non-oriented electrical steel sheet, a rotor core, a motor, and a method for producing a non-oriented electrical steel sheet. PREVIOUS TECHNIQUE

[0002] Non-oriented electrical steel sheets are widely used as a raw material for motor cores (iron cores). To obtain a high-efficiency motor core, a non-oriented electrical steel sheet must exhibit excellent iron loss. Therefore, to produce non-oriented electrical steel sheets with excellent iron loss, higher alloy grade steel sheets are increasingly being produced.

[0003] A motor core includes a stator core that serves as a stator and a rotor core that serves as a rotor. Between the stator core and the rotor core, for the following reasons, the rotor core in particular is required to have both high strength and excellent magnetic properties (reduced iron loss deterioration). In recent years, motors for use in electric vehicles and hybrid vehicles are being designed to increase motor power by increasing the motor's rotational speed. Therefore, the loads applied to the rotor cores, which are rotors, during motor operation are increasing. Therefore, rotor cores are required to have high strength. Furthermore, since the rotor core is fixed to a rotating shaft, the rotor core is difficult to cool. Therefore, thermal management of the rotor core is also important.The loss of iron from a non-oriented electrical steel plate ultimately transforms into heat. Therefore, from... Petition 870250084752, dated 09 / 19 / 2025, page 8 / 111 2 / 86 From the point of view of rotor core thermal management, it is also necessary to reduce deterioration due to iron loss from non-oriented electrical steel sheets.

[0004] A non-oriented electrical steel sheet with high strength and excellent magnetic properties is proposed in Japanese Patent Application Publication No. 2008-050686 (Patent Literature 1). According to Patent Literature 1, high strength and excellent magnetic properties are obtained through proper adjustment of the chemical composition. List of Citations Patent Literature Patent Literature 1: Publication of Japanese Patent Application No. 2008-050686 SUMMARY OF DESCRIPTION Technical Problem

[0005] In this context, when producing a rotor core from non-oriented electrical steel sheet, the non-oriented electrical steel sheet is subjected to blanking (punching / stamping) to produce a blanking cut product, as a raw material for the rotor core. When using high-alloy, high-strength non-oriented electrical steel sheet, it can be difficult to cut the steel sheet into the desired shape during blanking, and in some cases, the dimensional accuracy of the blanking cut product obtained after blanking may decrease. Specifically, irregularities may occur on the end face of a blanking cut product (blanking cut end face) after blanking.If an irregularity occurs on the cut end face of the blanking, when the cut blanking product is mounted on an engine, it will be difficult for the cut blanking product to come into close contact with other parts, such as a magnet, a shaft, or the engine housing. Petition 870250084752, dated 09 / 19 / 2025, page 9 / 111 3 / 86 motor, at the contact interfaces with other parts. Consequently, a problem will arise in the fixing of the motor core. In addition, a problem will also arise with heat dissipation in relation to the aforementioned thermal management of the motor core. On the other hand, shear deformation introduced in a non-oriented electrical steel sheet causes deterioration due to iron loss. Consequently, the amount of heat generated in the motor core increases. Recently, rotor core raw materials are increasingly being cut into complex shapes using blanking to improve their functionality. Therefore, the proportion of a blanked end face in rotor core raw materials has increased. As a result, reducing the deterioration due to iron loss caused by shear deformation introduced into the rotor core raw material during blanking is also becoming increasingly important.

[0006] One objective of the present description is to provide a non-oriented electrical steel sheet in which high strength and excellent magnetic properties are obtained and which has excellent dimensional accuracy after blanking, as well as a rotor core, a motor and a method for producing the non-oriented electrical steel sheet. Solution to the Problem

[0007] A non-oriented electrical steel sheet of the present description consists of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0a 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0a 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0a Petition 870250084752, dated 09 / 19 / 2025, p. 10 / 111 4 / 86 0.0030%, with the remainder being Fe and impurities, and satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2) and, if a corresponding element is not contained, 0 is replaced by the corresponding element symbol.

[0008] In addition, in non-oriented electrical steel sheet, the tensile strength TS is greater than 570 MPa.

[0009] In addition, in non-oriented electrical steel sheet, when the stress at 2.0% strain is expressed as Y2,o (MPa) and the yield strength is expressed as YS (MPa), the work hardening degree WH defined by Formula (3) is less than 15 MPa. WH = Y2,0 -YS (3)

[0010] In the non-oriented electrical steel sheet, moreover, the average grain size D (μm) satisfies Formula (4) and an elongation of elasticity is 0.5% or more: D < 80-Si x10 (4) where the content of a corresponding element in mass percentage is replaced by the symbol of an element in Formula (4) and, if the corresponding element is not contained, 0 is replaced by the symbol of the corresponding element.

[0011] A rotor core of the present description includes a plurality of rotor core raw materials stacked together.

[0012] The raw material of the rotor core consists, in % by mass, of Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: Petition 870250084752, dated 09 / 19 / 2025, p. 11 / 111 5 / 86 at 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2), and if a corresponding element is not contained, 0 is replaced by the corresponding element symbol.

[0013] In addition, the rotor core raw material has a tensile strength TS greater than 570 MPa.

[0014] In the rotor core raw material, moreover, when the stress at 2.0% strain is expressed as Y2.0 (MPa) and the yield strength is expressed as YS (MPa), the work hardening degree WH defined by Formula (3) is less than 15 MPa. WH = Y2,0-YS (3)

[0015] In the rotor core raw material, moreover, the average grain size D (°m) satisfies Formula (4) and the elongation of elasticity is 0.5% or more: D < 80-Si x10 (4) where the content of a corresponding element in mass percentage is replaced by the symbol of an element in Formula (4) and, if the corresponding element is not contained, 0 is replaced by the symbol of the corresponding element.

[0016] A motor of the present description includes the rotor core described above.

[0017] A method for producing a non-oriented electrical steel sheet of the present description includes a rolling process Petition 870250084752, dated 09 / 19 / 2025, page 12 / 111 6 / 86 hot, a cold rolling process and a final annealing process.

[0018] In the hot rolling process, a plate is subjected to hot rolling to produce a hot-rolled steel sheet.

[0019] In the cold rolling process, hot-rolled steel sheet is subjected to cold rolling to produce a cold-rolled steel sheet.

[0020] In the final annealing process, the cold-rolled steel sheet is subjected to final annealing in a final annealing furnace.

[0021] In the final annealing process, the cold-rolled steel sheet is annealed at a maximum attainable temperature T1 of 950°C or less. Furthermore, the stress TE applied to the cold-rolled steel sheet at the maximum attainable temperature T1 is adjusted to 2.0 to 10.0 MPa. Additionally, the residence time t0 (seconds) between the annealing temperature T1 and 700°C in a heating zone, an immersion zone, and a cooling zone of the final annealing furnace, and the residence time t1 (seconds) between 700 and 500°C in the cooling zone are adjusted to satisfy Formulas (A) and (B). t1-t0 > 0 (A) t1 / t0 < 3.0 (B)

[0022] Furthermore, in one or more selected locations of the heating zone, the immersion zone and the cooling zone in a temperature range of 500°C or more in a furnace atmosphere of the final annealing furnace, the ratio of a partial pressure of water vapor PH20 (atm) to the partial pressure of hydrogen PH2 (atm) becomes greater than 0.05 or the oxygen concentration becomes greater than 0.010%. Petition 870250084752, dated 09 / 19 / 2025, page 13 / 111 7 / 86

[0023] Furthermore, the CG temperature gradient in the longitudinal direction of cold-rolled steel sheet in a cooling process becomes 20°C / m or less. Advantageous Effects of the Invention

[0024] In the non-oriented electrical steel sheet of the present description, high strength and excellent magnetic properties are obtained, and the non-oriented electrical steel sheet exhibits excellent dimensional accuracy after blanking. The rotor core and motor of the present description are produced using the non-oriented electrical steel sheet of the present description as raw material. The method for producing a non-oriented electrical steel sheet of the present description allows the production of the aforementioned non-oriented electrical steel sheet. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram showing an example of a stress-strain curve.

[0026] Figure 2 is a schematic diagram showing an example of a stress-strain curve different from Figure 1.

[0027] Figure 3 is a schematic diagram to describe a method for determining elongation due to elasticity in a case where the maximum yield point is not clear on a stress-strain curve.

[0028] Figure 4 is a plan view illustrating an example of a rotor core of the present embodiment.

[0029] Figure 5 is a plan view illustrating an example of a stator core of the present embodiment.

[0030] Figure 6 is a schematic diagram to describe a definition of cut flatness in blanking in a dimensional accuracy evaluation test after cutting in blanking in the examples. DESCRIPTION OF MODALITIES Petition 870250084752, dated 09 / 19 / 2025, page 14 / 111 8 / 86

[0031] The present inventors conducted studies and investigations into the cause of the decrease in dimensional accuracy and the cause of the deterioration of the magnetic properties of a blanking product (raw material for a rotor core or similar) when a non-oriented electrical steel sheet that has high strength and excellent magnetic properties is blanking. As a result, the present inventors reached the following conclusions.

[0032] During blanking, when an electrically unoriented steel sheet is pushed into a die by a blanking punch, a portion of the steel sheet that is close to the surface of the steel sheet being pushed by the punch is pushed into the die in the thickness direction and processed. Conversely, the portion of the steel sheet that is in contact with the die is pulled towards the chip side. Thus, the direction of the stress applied to a steel sheet during blanking changes in a complex manner. Therefore, after the steel sheet is fractured during blanking, the degree of springback when the stress is released differs in the thickness direction of the steel sheet. As a result, irregularities occur on the end face (blanking end face) of the blanked product, and the dimensional accuracy of the blanked product decreases.This decrease in dimensional accuracy is particularly noticeable in cases where the tensile strength of the steel plate is greater than 570 MPa.

[0033] When a steel plate is deformed by blanking, a plurality of dislocations are introduced into the steel plate. As the dislocations introduced by deformation interlock and work hardening progresses, the degree of springback that occurs when stress is released after fracture of the steel plate during blanking increases further. As a result, irregularities occur on the end face of the cut product. Petition 870250084752, dated 09 / 19 / 2025, page 15 / 111 9 / 86 blanking (end face cut in blanking) after cutting in blanking and the dimensional accuracy of the product cut in blanking decreases.

[0034] Furthermore, in a non-oriented electrical steel sheet, dislocations are introduced by the shear deformation applied during blanking. The magnetic properties deteriorate due to the introduced dislocations. The progression of work hardening means, in other words, that the dislocations become entangled and remain in the steel sheet. Therefore, the iron loss in the steel sheet deteriorates further as work hardening progresses.

[0035] Considering the above mechanism, the present inventors considered that, if the work hardening degree could be reduced, the dimensional accuracy of a blanking cut product after blanking would improve and, moreover, deterioration due to iron loss could be suppressed. As a result of further studies, the present inventors found that, if the work hardening degree WH defined by Formula (3) is less than 15 MPa, excellent dimensional accuracy and excellent magnetic properties will be obtained after blanking. WH = Y2,o-YS (3)

[0036] The present inventors also investigated means of making the work hardening degree WH less than 15 MPa. As a result, the present inventors obtained the following discovery.

[0037] Silicon (Si) restricts the slip systems along which dislocations can move. If the Si content in a steel sheet is increased, the slip systems along which dislocations can move will be restricted. Therefore, the Petition 870250084752, dated 09 / 19 / 2025, page 16 / 111 10 / 86 Interlocking of dislocations due to the occurrence of cross-slips will be suppressed. As a result, the increase in dislocation density will be suppressed.

[0038] Furthermore, dissolved C and dissolved N in a steel plate tend to attach to dislocations. It is difficult for dislocations to which dissolved C or dissolved N are attached to move. Therefore, dislocations to which dissolved C or dissolved N are attached tend to interlock with dislocations that are in motion. As a result, variations in the density of dislocations in the steel plate arise. To decrease the number of these dislocations to which dissolved C or dissolved N are attached, it is effective to reduce the dissolved C and dissolved N in the steel plate.

[0039] To reduce dissolved C or dissolved N in a steel plate, it is sufficient to contain elements with a high affinity for C and / or N in the steel plate, thus fixing the C and N as precipitates. Si, Ti, and Zr have a high affinity for C and N. Nb, V, Mo, and Cr have a high affinity for C. In addition, Al, La, and Ce have a high affinity for N. Therefore, if one or more of these groups of elements are present, the dissolved C or dissolved N in the steel plate can be reduced.

[0040] The present inventors conducted studies from the point of view of chemical composition based on the considerations described above. As a result, the present inventors considered that if a non-oriented electrical steel sheet has a chemical composition consisting of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to Petition 870250084752, dated 09 / 19 / 2025, p. 17 / 111 11 / 86 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and also satisfies Formula (1) and Formula (2), excellent magnetic properties will be obtained and the dimensional accuracy after blanking will be improved, while a tensile strength TS greater than 570 MPa is obtained: Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each The symbol of an element in Formula (1) and Formula (2), and if a corresponding element is not contained, 0 is replaced by the symbol of the corresponding element.

[0041] However, even when non-oriented electrical steel sheets met the characteristics described above, although they exhibited high strength and excellent magnetic properties, there were still cases where it was not possible to obtain sufficient dimensional accuracy after blanking. Thus, the present inventors carried out further studies and obtained the following discovery.

[0042] When performing blanking cutting, the degree of springback increases as work hardening progresses. However, if the percentage of elongation at elasticity, in which deformation occurs without work hardening, is increased, the non-uniformity of deformation in the thickness direction will be reduced and, as a result, dimensional accuracy will be improved. If the elongation at elasticity is 0.5% or more, the dimensional accuracy after blanking cutting will be improved even further.

[0043] On the other hand, a tendency for decreasing elongation was observed as the Si content increased. The reason for this is believed to be as follows. As mentioned above, Si is considered to suppress dislocation entanglement. Petition 870250084752, dated 09 / 19 / 2025, page 18 / 111 12 / 86 and therefore contributes to the suppression of work hardening. However, work hardening is also caused by the accumulation of dislocations. If the Si content is increased, due to the slip systems being restricted, the sources of dislocation generation are limited. It is considered that, as a result, the elongation decreases.

[0044] Based on the above findings, the present inventors believed that increasing the sources of dislocation generation and dispersing the sources of dislocation generation would be effective in increasing the elastic elongation. As a result of further studies, it was revealed that when the grain size is reduced to increase the number of crystalline grain boundaries, which are sources of dislocation generation, the elastic elongation increases. Specifically, the present inventors found that if an average grain size D satisfies Formula (4), it will be easy for the elastic elongation to reach 0.5% or more, and the dimensional accuracy of a blanking cut product after blanking cut will be improved: D < 80-Si x10 (4) where, the Si content in mass percent in the non-oriented electrical steel sheet is replaced by Si in Formula (4).

[0045] The essence of the non-oriented electrical steel sheet of the present embodiment, which was completed based on the technical idea described above, is as follows.

[0046] A non-oriented electrical steel sheet according to a first aspect consists of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to Petition 870250084752, dated 09 / 19 / 2025, p. 19 / 111 13 / 86 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0a 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0a 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0a 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2), and if a corresponding element is not contained, 0 is replaced by the corresponding element symbol.

[0047] In addition, in non-oriented electrical steel sheet, the tensile strength TS is greater than 570 MPa.

[0048] In the non-oriented electrical steel sheet, moreover, when the stress at 2.0% strain is expressed as Y2.0 (MPa) and the yield strength is expressed as YS (MPa), the work hardening degree WH defined by Formula (3) is less than 15 MPa. WH = Y2,0-YS (3)

[0049] In the non-oriented electrical steel sheet according to the first aspect, moreover, the average grain size D (pm) satisfies Formula (4) and the elongation of elasticity is 0.5% or more: D < 80-Si x10 (4) where the content of a corresponding element in mass percent is replaced by the symbol of an element in Formula (4) and, if the corresponding element is not contained, 0 is replaced by the symbol of the corresponding element.

[0050] A non-oriented electrical steel sheet according to a second aspect is in accordance with a non-oriented electrical steel sheet according to the first aspect, wherein the non-oriented electrical steel sheet contains one or more types of selected elements. Petition 870250084752, dated 09 / 19 / 2025, p. 20 / 111 14 / 86 of a group consisting of, in % by mass, Zr: 0.0001 to 0.0100%, Nb: 0.0001 to 0.0100%, V: 0.0001 to 0.0100%, Mo: 0.001 to 0.100%, Cr: 0.001 to 2.000%, La: 0.0001 to 0.0100%, Ce: 0.0001 to 0.0100%, B: 0.0001 to 0.0010%, Zn: 0.0001 to 0.0050%, Ga: 0.0001 to 0.0050%, Ge: 0.0001 to 0.0050%, As: 0.0001 to 0.0100%, Ni: 0.001 to 0.500%, Cu: 0.001 to 0.500%, Sn: 0.001 to 0.200%, Sb: 0.001 to 0.100%, Ca: 0.0001 to 0.0050%, Nd: 0.0001 to 0.0010% and Mg: 0.0001 to 0.0030%.

[0051] A rotor core according to a first aspect includes a plurality of rotor core raw materials stacked together.

[0052] The raw material of the rotor core consists of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2), and if a corresponding element is not contained,0 is replaced by the symbol of the corresponding element.

[0053] In addition, the tensile strength TS in the rotor core raw material is greater than 570 MPa.

[0054] In the raw material of the rotor core, moreover, when the stress at 2.0% strain is expressed as Y2.0 (MPa) and the limit of Petition 870250084752, dated 09 / 19 / 2025, p. 21 / 111 15 / 86 elasticity is expressed as YS (MPa), the work hardening degree WH defined by Formula (3) is less than 15 MPa. WH = Y2,o-YS (3)

[0055] In the rotor core raw material, moreover, the average grain size D (μm) satisfies Formula (4) and the elongation of elasticity is 0.5% or more: D < 80-Si x10 (4) where the content of a corresponding element in mass percentage is replaced by the symbol of an element in Formula (4) and, if the corresponding element is not contained, 0 is replaced by the symbol of the corresponding element.

[0056] A rotor core according to a second aspect is in accordance with the rotor core according to the first aspect, wherein the raw material of the rotor core contains one or more types of elements selected from a group consisting of, in % by mass, Zr: 0.0001 to 0.0100%, Nb: 0.0001 to 0.0100%, V: 0.0001 to 0.0100%, Mo: 0.001 to 0.100%, Cr: 0.001 to 2.000%, La: 0.0001 to 0.0100%, Ce: 0.0001 to 0.0100%, B: 0.0001 to 0.0010%, Zn: 0.0001 to 0.0050%, Ga: 0.0001 to 0.0050%, Ge: 0.0001 to 0.0050%, As: 0.0001 to 0.0100%, Ni: 0.001 to 0.500%, Cu: 0.001 to 0.500%, Sn: 0.001 to 0.200%, Sb: 0.001 to 0.100%, Ca: 0.0001 to 0.0050%, Nd: 0.0001 to 0.0010% and Mg: 0.0001 to 0.0030%.

[0057] A motor of the present embodiment includes the rotor core according to the first or second aspect.

[0058] A method for producing a non-oriented electrical steel sheet of the present embodiment is a method for producing the non-oriented electrical steel sheet according to the first or second aspects and includes a hot rolling process, a cold rolling process and a final annealing process.

[0059] In the hot rolling process, a plate is subjected Petition 870250084752, dated 09 / 19 / 2025, page 22 / 111 16 / 86 hot rolling to produce a hot-rolled steel sheet.

[0060] In the cold rolling process, hot-rolled steel sheet is subjected to cold rolling to produce a cold-rolled steel sheet.

[0061] In the final annealing process, the cold-rolled steel sheet is subjected to final annealing in a final annealing furnace.

[0062] In the final annealing process, the cold-rolled steel sheet is annealed at a maximum attainable temperature T1 of 950°C or less. Furthermore, the stress TE applied to the cold-rolled steel sheet at the maximum attainable temperature T1 is adjusted to 2.0 to 10.0 MPa. Additionally, the residence time t0 (seconds) between the annealing temperature T1 and 700°C in a heating zone, an immersion zone, and a cooling zone of the final annealing furnace, and the residence time t1 (seconds) between 700 and 500°C in the cooling zone are adjusted to satisfy Formulas (A) and (B). t1-t0 > 0 (A) t1 / t0 < 3.0 (B)

[0063] Furthermore, in one or more selected locations of the heating zone, the immersion zone and the cooling zone in a temperature range of 500°C or more in a furnace atmosphere of the final annealing furnace, the ratio of the partial pressure of water vapor PH20 (atm) to the partial pressure of hydrogen PH2 (atm) becomes greater than 0.05 or the oxygen concentration becomes greater than 0.010%.

[0064] Furthermore, the CG temperature gradient in the longitudinal direction of cold-rolled steel sheet in a cooling process becomes 20°C / m or less. Petition 870250084752, dated 09 / 19 / 2025, page 23 / 111 17 / 86

[0065] Next, the non-oriented electrical steel sheet of the present embodiment will be described in detail. Characteristics of the Non-Oriented Electrical Steel Sheet of the Present Model

[0066] The non-oriented electrical steel sheet of the present embodiment satisfies characteristics 1 to 5 below. Feature 1

[0067] The chemical composition consists of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities. Feature 2

[0068] The chemical composition described above also satisfies the Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2), and if a corresponding element is not contained, 0 is replaced by the corresponding element symbol. Characteristic 3

[0069] The tensile strength TS is greater than 570 MPa. Feature 4

[0070] When stress at 2.0% strain is expressed as Y2.0 (MPa) and the yield strength is expressed as YS (MPa), the degree Petition 870250084752, dated 09 / 19 / 2025, p. 24 / 111 18 / 86 of work hardening WH defined by Formula (3) is less than 15 MPa. WH = Y2,o-YS (3) Feature 5

[0071] The average grain size D (μm) satisfies Formula (4) and the elongation of elasticity is 0.5% or more: D < 80-Si x10 (4)

[0072] where the content of the corresponding element in mass percentage is replaced by the element symbol in Formula (4).

[0073] Characteristic 1 to characteristic 5 are described below. (Characteristic 1) - Regarding Chemical Composition

[0074] The chemical composition of the non-oriented electrical steel sheet of the present embodiment contains the following elements. Note that the symbol % in relation to the content of elements in the chemical composition of the non-oriented electrical steel sheet and the rotor core raw material means percentage by mass, unless otherwise specified. In addition, the non-oriented electrical steel sheet is also simply referred to as steel sheet. Yes: 3.1 to 4.5%

[0075] Silicon (Si) increases the resistivity of the steel sheet and reduces eddy current loss. Si also dissolves in the steel sheet and increases the electrical resistance of the non-oriented steel sheet. Furthermore, Si restricts the slip systems along which dislocations can move. In this way, Si can suppress dislocation entanglement and the increase in dislocation density. Therefore, dimensional accuracy after blanking can be increased. If the Si content is less than 3.1%, the aforementioned advantageous effects will not be sufficiently achieved. Petition 870250084752, dated 09 / 19 / 2025, page 25 / 111 19 / 86

[0076] On the other hand, if the Si content is greater than 4.5%, the cutting capacity in blanking of non-oriented electrical steel sheet will decrease.

[0077] Therefore, the Si content is 3.1 to 4.5%.

[0078] A preferred minimum limit for Si content is 3.2%, more preferably 3.3%, and even more preferably 3.4%.

[0079] A preferred maximum limit for Si content is 4.4%, more preferably 4.3%, and even more preferably 4.2%. C: 0.0025% or less

[0080] Carbon (C) is inevitably present. That is, the C content is greater than 0%. C increases the strength of the steel plate.

[0081] However, if the C content is greater than 0.0025%, the amount of dissolved C in the steel plate will be excessively large. In this case, the dissolved C will attach to dislocations during blanking and restrict the movement of dislocations. If the number of dislocations to which the dissolved C is attached is large, the density of interlocking dislocations will also increase. As a result, irregularities are likely to occur in the blanked product after blanking, and the dimensional accuracy after blanking will decrease. If the C content is greater than 0.0025%, in addition, an excessively large amount of carbides and / or carbonitrides will be formed. As a result, iron loss will deteriorate.

[0082] Therefore, the C content is 0.0025% or less.

[0083] A preferred minimum limit for the C content is 0.0001%, more preferably it is 0.0005%, even more preferably it is 0.0010%, even more preferably it is 0.0012%, even more preferably it is 0.0014% and, even more preferably, it is 0.0016%.

[0084] A preferred maximum limit for the C content is 0.0024%, more preferably 0.0023%, even more preferably 0.0022% and, Petition 870250084752, dated 09 / 19 / 2025, page 26 / 111 20 / 86, or more preferably, is 0.0021%. N: 0.0025% or less

[0085] Nitrogen (N) is inevitably present. That is, the N content is greater than 0%. NO increases the strength of the steel plate. Even if a small amount of N is present, the aforementioned advantageous effect will be achieved to some extent.

[0086] However, if the N content is greater than 0.0025%, the amount of dissolved N in the steel sheet will be excessively large. In this case, the dissolved N will bind to dislocations during blanking and restrict the movement of dislocations. If the number of dislocations to which the dissolved N binds is large, the density of interlocking dislocations will also increase. As a result, irregularities are likely to occur in the blanked product after blanking, and the dimensional accuracy after blanking will decrease. If the N content is greater than 0.0025%, in addition, an excessively large amount of nitrides and / or carbonitrides will form. As a result, iron loss will deteriorate.

[0087] Therefore, the N content is 0.0025% or less.

[0088] A preferred minimum limit for the N content is 0.0001%, more preferably it is 0.0005%, even more preferably it is 0.0010%, even more preferably it is 0.0012%, even more preferably it is 0.0014% and, even more preferably, it is 0.0016%.

[0089] A preferred maximum limit for the N content is 0.0024%, more preferably it is 0.0023%, even more preferably it is 0.0022% and, even more preferably, it is 0.0021%. O: 0.0400% or less

[0090] Oxygen (O) is inevitably present. That is, the O content is greater than 0%. OO forms oxides and reduces the magnetic properties of the steel sheet. Petition 870250084752, dated 09 / 19 / 2025, page 27 / 111 21 / 86

[0091] Therefore, the O content is 0.0400% or less.

[0092] The O content is preferably as low as possible. However, excessive reduction of the O content will increase the cost of production. Therefore, from the point of view of industrial productivity, a preferable minimum limit for the O content is 0.0001%, more preferably 0.0010%, and even more preferably 0.0020%.

[0093] A preferred maximum limit for the O content is 0.0370%, more preferably 0.0350%, even more preferably 0.0300%, and even more preferably 0.0200%. P: 0.100% or less

[0094] Phosphorus (P) is inevitably present. That is, the P content is greater than 0%. OP increases the strength of the steel plate. Even if a small amount of P is present, the aforementioned advantageous effect will be achieved to some extent.

[0095] However, if the P content is greater than 0.100%, the steel sheet will become brittle and its workability will decrease, and cracks may occur in the steel sheet during cold rolling.

[0096] Therefore, the content of P is 0.100% or less.

[0097] A preferred minimum limit for P content is 0.001%, more preferably 0.005%, and even more preferably 0.007%.

[0098] A preferred maximum limit for P content is 0.090%, more preferably 0.080%, and even more preferably 0.070%. S: 0.0050% or less

[0099] Sulfur (S) is an impurity that is inevitably present. That is, the S content is greater than 0%. It forms MnS and causes deterioration by iron loss.

[0100] Therefore, the content of S is 0.0050% or less.

[0101] The sulfur content is preferably as low as possible. However, excessive reduction of the sulfur content will increase the cost of production. Therefore, from the point of view of industrial productivity, a minimum limit Petition 870250084752, dated 09 / 19 / 2025, page 28 / 111 22 / 86 The preferred value for the S content is 0.0001%, more preferably 0.0003%, and even more preferably 0.0005%.

[0102] A preferred maximum limit for the S content is 0.0047%, more preferably it is 0.0045%, even more preferably it is 0.0040%, even more preferably it is 0.0030%, even more preferably it is 0.0025% and, even more preferably, it is 0.0020%. Regarding the elements that decrease dissolved C and / or dissolved N

[0103] The chemical composition of the non-oriented electrical steel sheet of the present embodiment also contains Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100% and Ce: 0 to 0.0100%. Each of these elements fixes the dissolved C and / or dissolved N in the steel sheet to form precipitates, such as carbides, carbonitrides or nitrides. As a result, these elements decrease the amount of dissolved C and N, factors that reduce dimensional accuracy after blanking. Ti: 0.0100% or less

[0104] Titanium (Ti) is inevitably present. That is, the Ti content is greater than 0%. Ti combines with C and / or N to form precipitates and, in this way, decreases the amount of dissolved C and dissolved N. In this way, Ti increases dimensional accuracy after blanking. Ti also increases the strength of the steel sheet by forming precipitates. Even if a small amount of Ti is present, the aforementioned advantageous effects will be obtained to some extent.

[0105] However, if the Ti content is greater than 0.0100%, excessive precipitates will form and the magnetic properties will deteriorate.

[0106] Therefore, the Ti content is 0.0100% or less. Petition 870250084752, dated 09 / 19 / 2025, p. 29 / 111 23 / 86

[0107] A preferred minimum limit for the Ti content is 0.0001%, more preferably 0.0005%, and even more preferably 0.0010%.

[0108] A preferred maximum limit for the Ti content is 0.0090%, more preferably 0.0080%, even more preferably 0.0070%, even more preferably 0.0060%, and even more preferably 0.0055%. Mn: 2.0% or less

[0109] Manganese (Mn) is inevitably present. That is, the Mn content is greater than 0%. Mn combines with C to form carbides, thus decreasing the amount of dissolved C. Mn also increases the resistivity of the steel plate, thus reducing eddy current loss. Even if a small amount of Mn is present, the aforementioned advantageous effects will be obtained to some extent.

[0110] However, if the Mn content is greater than 2.0%, the magnetic flux density of the steel plate will decrease.

[0111] Therefore, the Mn content is 2.0% or less.

[0112] A preferred minimum limit for Mn content is 0.1%, more preferably 0.2%, and even more preferably 0.5%.

[0113] A preferred maximum limit for Mn content is 1.8%, more preferably 1.6%, and even more preferably 1.4%. Al: 1,500% or less

[0114] Aluminum (Al) is inevitably present. That is, the Al content is greater than 0%. Al combines with N to form nitrides, thus decreasing the amount of dissolved N. Consequently, dimensional accuracy after blanking increases. Al also increases the strength of the steel sheet by forming nitrides. Even if a small amount of Al is present, the aforementioned advantageous effects will be obtained to some extent. Petition 870250084752, dated 09 / 19 / 2025, page 30 / 111 24 / 86

[0115] However, if the Al content is greater than 1,500%, excessive oxides will form on the steel sheet and the magnetic properties will deteriorate.

[0116] Therefore, the Al content is 1,500% or less.

[0117] A preferred minimum limit for Al content is 0.001%, more preferably 0.004%, even more preferably 0.005%, even more preferably 0.010%, even more preferably 0.050%, and even more preferably 0.100%.

[0118] A preferred maximum limit for Al content is 1.450%, more preferably 1.400%, even more preferably 1.300%, even more preferably 1.100% and, even more preferably, 0.900%.

[0119] Note that, in the present description, the term Al content means the content of soluble Al (acid-soluble Al). Zr: 0 to 0.0100%

[0120] Zirconium (Zr) does not need to be contained. That is, the content of Zr could be 0%.

[0121] When contained, in other words, when the Zr content is greater than 0%, Zr combines with C and / or N to form precipitates, thus decreasing the amount of dissolved C and dissolved N. In this way, Zr increases dimensional accuracy after blanking. Zr also increases the strength of the steel sheet through the formation of precipitates. Even if a small amount of Zr is contained, the aforementioned advantageous effects will be obtained to some extent.

[0122] However, if the Zr content is greater than 0.0100%, excessive precipitate formation will occur, which will deteriorate the magnetic properties.

[0123] Therefore, the content of Zr is from 0 to 0.0100%.

[0124] A preferred minimum limit for Zr content is 0.0001%, more preferably 0.0005%, and even more preferably 0.0010%. Petition 870250084752, dated 09 / 19 / 2025, p. 31 / 111 25 / 86

[0125] A preferred maximum limit for Zr content is 0.0095%, more preferably 0.0090%, even more preferably 0.0080%, and even more preferably 0.0070%. Nb: 0 to 0.0100%

[0126] Niobium (Nb) does not need to be included. That is, the content of Nb can be 0%.

[0127] When contained, Nb combines with C to form carbides, thereby decreasing the amount of dissolved C. In this way, Nb increases dimensional accuracy after blanking. Nb also increases the strength of the steel sheet through the formation of carbides. Even if a small amount of Nb is contained, the aforementioned advantageous effects will be obtained to some extent.

[0128] However, if the Nb content is greater than 0.0100%, excessive carbide formation will occur, which will deteriorate the magnetic properties.

[0129] Therefore, the Nb content is 0 to 0.0100%.

[0130] A preferred minimum limit for Nb content is 0.0001%, more preferably 0.0005%, and even more preferably 0.0010%.

[0131] A preferred maximum limit for Nb content is 0.0090%, more preferably 0.0080%, even more preferably 0.0070%, even more preferably 0.0050%, even more preferably 0.0040%, even more preferably 0.0030% and, even more preferably, 0.0025%. V: 0 to 0.0100%

[0132] Vanadium (V) does not need to be included. That is, the content of V could be 0%.

[0133] When contained, in other words, when the V content is greater than 0%, V combines with C to form carbides, thus decreasing the amount of dissolved C. In this way, V Petition 870250084752, dated 09 / 19 / 2025, p. 32 / 111 26 / 86 increases dimensional accuracy after blanking. OV also increases the strength of the steel sheet through carbide formation. Even if a small amount of V is present, the aforementioned advantageous effects will be achieved to some extent.

[0134] However, if the V content is greater than 0.0100%, excessive carbide formation will occur, which will deteriorate the magnetic properties.

[0135] Therefore, the V content is from 0 to 0.0100%.

[0136] A preferred minimum limit of V content is 0.0001%, more preferably 0.0005%, and even more preferably 0.0010%.

[0137] A preferred maximum limit of V content is 0.0090%, more preferably 0.0080%, even more preferably 0.0070%, even more preferably 0.0050%, even more preferably 0.0040%, even more preferably 0.0030%, and even more preferably 0.0025%. Mo: 0 to 0.100%

[0138] Molybdenum (Mo) does not need to be present. That is, the Mo content can be 0%.

[0139] When contained, in other words, when the Mo content is greater than 0%, Mo combines with C to form carbides, thus decreasing the amount of dissolved C. In this way, Mo increases dimensional accuracy after blanking. Mo also increases the strength of the steel sheet through the formation of carbides. Even if a small amount of Mo is contained, the aforementioned advantageous effects will be obtained to some extent.

[0140] However, if the Mo content is greater than 0.100%, excessive carbide formation will occur, which will deteriorate the magnetic properties.

[0141] Therefore, the Mo content is from 0 to 0.100%.

[0142] A preferred minimum limit for Mo content is 0.001%, plus Petition 870250084752, dated 09 / 19 / 2025, page 33 / 111 27 / 86 preferably is 0.005%, even more preferably is 0.010%, and even more preferably is 0.030%.

[0143] A preferred maximum limit for Mo content is 0.090%, more preferably 0.080%, and even more preferably 0.070%. Cr: 0 to 2,000%

[0144] Chromium (Cr) does not need to be present. That is, the Cr content can be 0%.

[0145] When contained, in other words, when the Cr content is greater than 0%, Cr combines with C to form carbides, thus decreasing the amount of dissolved C. In this way, Cr increases dimensional accuracy after blanking. Cr also increases the strength of the steel sheet. Even if a small amount of Cr is contained, the aforementioned advantageous effects will be obtained to some extent.

[0146] However, if the Cr content is greater than 2.000%, excessive carbide formation will occur. In this case, the magnetic properties will deteriorate.

[0147] Therefore, the Cr content is from 0 to 2,000%.

[0148] A preferred minimum limit for Cr content is 0.001%, more preferably 0.005%, even more preferably 0.010%, and even more preferably 0.050%.

[0149] A preferred maximum limit for Cr content is 1.800%, more preferably 1.500%, even more preferably 1.400% and, even more preferably, 1.000%. La: 0 to 0.0100%

[0150] Lanthanum (La) is an optional element and does not need to be present. That is, the La content can be 0%.

[0151] When contained, in other words, when the La content is greater than 0%, La combines with N to form nitrides and thus decreases the amount of dissolved N. In this way, La increases Petition 870250084752, dated 09 / 19 / 2025, p. 34 / 111 28 / 86 dimensional accuracy after cutting in blanking. La also increases the strength of the steel sheet by forming nitrides. Even if a small amount of La is present, the aforementioned advantageous effects will be obtained to some extent.

[0152] However, if the La content is greater than 0.0100%, excessive nitride formation will occur in the steel sheet. In this case, the magnetic properties will deteriorate.

[0153] Therefore, the La content is 0 to 0.0100%.

[0154] A preferred minimum limit for the La content is 0.0001%, more preferably it is 0.0005%, even more preferably it is 0.0010% and, even more preferably, it is 0.0020%.

[0155] A preferred maximum limit for the La content is 0.0090%, more preferably it is 0.0080%, even more preferably it is 0.0075% and, even more preferably, it is 0.0070%. Ce: 0 to 0.0100%

[0156] Cerium (Ce) is an optional element and does not need to be present. That is, the Ce content can be 0%.

[0157] When contained, in other words, when the Ce content is greater than 0%, Ce combines with N to form nitrides and thus decreases the amount of dissolved N. In this way, Ce increases dimensional accuracy after blanking. Ce also increases the strength of the steel sheet by forming nitrides. Even if a small amount of Ce is contained, the aforementioned advantageous effects will be obtained to some extent.

[0158] However, if the Ce content is greater than 0.0100%, excessive nitride formation will occur in the steel sheet. In this case, the magnetic properties will deteriorate.

[0159] Therefore, the Ce content is from 0 to 0.0100%.

[0160] A preferred minimum limit for the Ce content is 0.0001%, more preferably 0.0005%, even more preferably 0.0010% and, Petition 870250084752, dated 09 / 19 / 2025, p. 35 / 111 29 / 86, or even more preferably, is 0.0015%.

[0161] A preferred maximum limit for the Ce content is 0.0090%, more preferably 0.0080%, and even more preferably 0.0070%.

[0162] The remainder of the chemical composition of the non-oriented electrical steel sheet of the present embodiment is Fe and impurities. Here, the term impurities refers to substances that, during the industrial production of the non-oriented electrical steel sheet, are mixed from ore or scrap used as raw material or from the production environment or similar. The levels of these impurities are permitted within a range that does not negatively affect the non-oriented electrical steel sheet of the present embodiment.

[0163] The non-oriented electrical steel sheet of the present embodiment may additionally contain B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%. Each of these elements is optional and does not need to be present. Each element will be described below. B, Zn, Ga, Ge and As

[0164] OB, Zn, Ga, Ge and As are impurities in the non-oriented electrical steel sheet of the present embodiment. B: 0 to 0.0010%

[0165] Boron (B) is an optional element and does not need to be present. That is, the B content can be 0%.

[0166] When contained, in other words, when the B content is greater than 0%, B forms nitrides. B nitrides inhibit recrystallization during final annealing.

[0167] Therefore, the content of B is from 0 to 0.0010%.

[0168] Excessive reduction of B content will increase the cost of production. Therefore, from the point of view of industrial productivity, a preferable minimum limit for B content is 0.0001%, more preferably Petition 870250084752, dated 09 / 19 / 2025, page 36 / 111 30 / 86 0.0002% and, even more preferably, 0.0003%.

[0169] A preferred maximum limit for B content is 0.0009%, more preferably 0.0008%, and even more preferably 0.0007%. Zn: 0 to 0.0050%

[0170] Zinc (Zn) is an optional element and does not need to be present. That is, the Zn content can be 0%.

[0171] When contained, in other words, when the Zn content is greater than 0%, no specific problem occurs, as long as the Zn content is 0.0050% or less.

[0172] Therefore, the Zn content is 0 to 0.0050%.

[0173] Excessive reduction of Zn content will increase the cost of production. Therefore, from the point of view of industrial productivity, a preferable minimum limit for Zn content is 0.0001%, more preferably 0.0002%, and even more preferably 0.0003%.

[0174] A preferred maximum limit for Zn content is 0.0020%, more preferably 0.0010%, and even more preferably 0.0005%. Ga: 0 to 0.0050%

[0175] Gallium (Ga) is an optional element and does not need to be present. That is, the Ga content can be 0%.

[0176] When contained, in other words, when the Ga content is greater than 0%, no specific problem occurs, as long as the Ga content is 0.0050% or less.

[0177] Therefore, the Ga content is 0 to 0.0050%.

[0178] Excessive reduction of Ga content will increase the cost of production. Therefore, from the point of view of industrial productivity, a preferable minimum limit for Ga content is 0.0001%, more preferably 0.0002%, and even more preferably 0.0003%.

[0179] A preferred maximum limit for the Ga content is 0.0040%, more preferably 0.0035%, even more preferably 0.0030%, even more preferably 0.0020%, even more preferably Petition 870250084752, dated 09 / 19 / 2025, page 37 / 111 31 / 86 0.0010%, and even more preferably, 0.0005%. Ge: 0 to 0.0050%

[0180] Germanium (Ge) is an optional element and does not need to be present. That is, the Ge content can be 0%.

[0181] When contained, in other words, when the Ge content is greater than 0%, no specific problem occurs, provided that the Ge content is 0.0050% or less.

[0182] Therefore, the Ge content is 0 to 0.0050%.

[0183] Excessive reduction of the Ge content will increase the cost of production. Therefore, from the point of view of industrial productivity, a preferable minimum limit for the Ge content is 0.0001%, more preferably 0.0002%, and even more preferably 0.0003%.

[0184] A preferred maximum limit for the Ge content is 0.0040%, more preferably it is 0.0035%, even more preferably it is 0.0030%, even more preferably it is 0.0020%, even more preferably it is 0.0010% and, even more preferably, it is 0.0005%. As: 0 to 0.0100%

[0185] Arsenic (As) is an optional element and does not need to be present. That is, the As content can be 0%.

[0186] When contained, in other words, when the As content is greater than 0%, no specific problem occurs, as long as the As content is 0.0100% or less.

[0187] Therefore, the As content is from 0 to 0.0100%.

[0188] Excessive reduction of the As content will increase the cost of production. Therefore, from the point of view of industrial productivity, a preferable minimum limit for the As content is 0.0001%, more preferably 0.0002%, even more preferably 0.0003%, even more preferably 0.0005% and, even more preferably, 0.0010%.

[0189] A preferred maximum limit for the As content is 0.0070%, more preferably 0.0060%, and even more preferably 0.0050%, Petition 870250084752, dated 09 / 19 / 2025, p. 38 / 111 32 / 86, or even more preferably, is 0.0030%. Ni e Cu

[0190] Ni and Cu are optional elements. Ni and Cu each increase the electrical resistance of the non-oriented steel sheet. Ni: 0 to 0.500%

[0191] Nickel (Ni) is an optional element and does not need to be present. That is, the Ni content can be 0%.

[0192] When contained, in other words, when the Ni content is greater than 0%, Ni increases the resistance of the non-oriented electrical steel sheet. Even if a small amount of Ni is contained, the aforementioned advantageous effect will be obtained to some extent.

[0193] However, if the Ni content is greater than 0.500%, the steel sheet will become brittle and its workability will decrease.

[0194] Therefore, the Ni content is 0 to 0.500%.

[0195] A preferred minimum limit for Ni content is 0.001%, more preferably 0.005%, even more preferably 0.010%, even more preferably 0.020%, even more preferably 0.050%, and even more preferably 0.100%.

[0196] A preferred maximum limit for Ni content is 0.450%, more preferably 0.400%, even more preferably 0.350%, even more preferably 0.300%, and even more preferably 0.250%. Cu: 0 to 0.500%

[0197] Copper (Cu) is an optional element and does not need to be present. That is, the Cu content can be 0%.

[0198] When contained, in other words, when the Cu content is greater than 0%, Cu increases the resistance of the non-oriented electrical steel sheet. Even if a small amount of Cu is contained, the aforementioned advantageous effect will be obtained to some extent.

[0199] However, if the Cu content is greater than 0.500%, the steel sheet will become brittle and its workability will decrease. Petition 870250084752, dated 09 / 19 / 2025, p. 39 / 111 33 / 86

[0200] Therefore, the Cu content is 0 to 0.500%.

[0201] A preferred minimum limit for Cu content is 0.001%, more preferably 0.005%, even more preferably 0.010%, even more preferably 0.030%, even more preferably 0.050%, and even more preferably 0.100%.

[0202] A preferred maximum limit for the Cu content is 0.450%, more preferably 0.400%, even more preferably 0.350%, even more preferably 0.250%, and even more preferably 0.150%. Sn and Sb

[0203] Sn and Sb are optional elements. Sn and Sb reduce iron loss from non-oriented electrical steel sheet. Sn: 0 to 0.200%

[0204] Tin (Sn) is an optional element and does not need to be present. That is, the Sn content can be 0%.

[0205] When contained, in other words, when the Sn content is greater than 0%, the Sn segregates on the surface of the steel sheet and suppresses oxidation and nitriding during final annealing. Furthermore, Sn improves the texture of the steel sheet and thus increases the magnetic flux density. As a result, the iron loss from the non-oriented electrical steel sheet decreases. Even if a small amount of Sn is contained, the aforementioned advantageous effect will be obtained to some extent.

[0206] However, if the Sn content is greater than 0.200%, the steel sheet will become brittle and its workability will decrease.

[0207] Therefore, the Sn content is from 0 to 0.200%.

[0208] A preferred minimum limit for Sn content is 0.001%, more preferably 0.003%, even more preferably 0.005%, even more preferably 0.010%, even more preferably 0.030%, and even more preferably 0.050%.

[0209] A preferred maximum limit for Sn content is 0.180%, plus Petition 870250084752, dated 09 / 19 / 2025, page 40 / 111 34 / 86 is preferably 0.160%, even more preferably 0.150%, and even more preferably 0.120%. Sb: 0 to 0.100%

[0210] Antimony (Sb) is an optional element and does not need to be present. That is, the Sb content can be 0%.

[0211] When contained, in other words, when the Sb content is greater than 0%, similar to Sn, Sb segregates on the surface of the steel sheet and suppresses oxidation and nitriding during final annealing. Furthermore, Sb improves the texture of the steel sheet and thus increases the magnetic flux density. As a result, the iron loss from the non-oriented electrical steel sheet decreases. Even if a small amount of Sb is contained, the aforementioned advantageous effect will be obtained to some extent.

[0212] However, if the Sb content is greater than 0.100%, the steel sheet will become brittle and its workability will decrease.

[0213] Therefore, the Sb content is from 0 to 0.100%.

[0214] A preferred minimum limit for Sb content is 0.001%, more preferably 0.005%, even more preferably 0.010%, and even more preferably 0.030%.

[0215] A preferred maximum limit for Sb content is 0.080%, more preferably 0.070%, even more preferably 0.060%, and even more preferably 0.050%. Ca, Nd and Mg

[0216] Ca, Nd, and Mg are optional elements. Ca, Nd, and Mg each promote grain growth during final annealing and improve the magnetic properties of non-oriented electrical steel sheet. Ca: 0 to 0.0050%

[0217] Calcium (Ca) is an optional element and does not need to be present. That is, the Ca content can be 0%. Petition 870250084752, dated 09 / 19 / 2025, page 41 / 111 35 / 86

[0218] When contained, in other words, when the Ca content is greater than 0%, Ca combines with S during the casting of molten steel and forms coarse precipitates, which are coarse sulfides and / or coarse oxysulfides. The grain size of the coarse precipitates is approximately 1 to 2 μm. The coarse precipitates adsorb fine inhibitors, such as MnS, TiN, and AlN, which have a grain size of approximately 100 nm, formed in the steel sheet during the production process, from the casting process onwards. In this way, the inhibition of grain growth by the inhibitors is suppressed during final annealing. Consequently, grain growth is promoted during final annealing. As a result, the magnetic properties of the electrically non-oriented steel sheet are enhanced. Even if a small amount of Ca is contained, the aforementioned advantageous effect will be obtained to some extent.

[0219] However, if the Ca content is greater than 0.0050%, excessive formation of coarse precipitates will occur. In this case, recrystallization and grain growth will be inhibited during the final annealing process.

[0220] Therefore, the Ca content is 0 to 0.0050%.

[0221] A preferred minimum limit for Ca content is 0.0001%, more preferably 0.0005%, and even more preferably 0.0010%.

[0222] A preferred maximum limit for Ca content is 0.0045%, more preferably 0.0040%, and even more preferably 0.0035%. Nd: 0 to 0.0010%

[0223] Neodymium (Nd) is an optional element and does not need to be present. That is, the Nd content can be 0%.

[0224] When contained, in other words, when the Nd content is greater than 0%, similar to Ca, Nd forms coarse precipitates and, Petition 870250084752, dated 09 / 19 / 2025, p. 42 / 111 36 / 86 thus suppresses the inhibition of grain growth by inhibitors during final annealing. Consequently, grain growth is promoted during final annealing. As a result, the magnetic properties of the non-oriented electrical steel sheet are enhanced. Even if a small amount of Nd is contained, the aforementioned advantageous effect will be obtained to some extent.

[0225] However, if the Nd content is greater than 0.0010%, excessive formation of coarse precipitates will occur. In this case, recrystallization and grain growth will be inhibited during the final annealing process.

[0226] Therefore, the Nd content is 0 to 0.0010%.

[0227] A preferred minimum limit for Nd content is 0.0001%, more preferably 0.0002%, and even more preferably 0.0003%.

[0228] A preferred maximum limit for Nd content is 0.0008%, more preferably 0.0006%, and even more preferably 0.0004%. Mg: 0 to 0.0030%

[0229] Magnesium (Mg) is an optional element and does not need to be present. That is, the Mg content can be 0%.

[0230] When contained, in other words, when the Mg content is greater than 0%, similar to Ca, Mg forms coarse precipitates and thus suppresses the inhibition of grain growth by inhibitors during final annealing. Consequently, grain growth is promoted during final annealing. As a result, the magnetic properties of the non-oriented electrical steel sheet are enhanced. Even if a small amount of Mg is contained, the aforementioned advantageous effect will be obtained to some extent.

[0231] However, if the Mg content is greater than 0.0030%, excessive formation of coarse precipitates will occur. In this case, recrystallization and grain growth will be inhibited during the final annealing process. Petition 870250084752, dated 09 / 19 / 2025, p. 43 / 111 37 / 86

[0232] Therefore, the Mg content is 0 to 0.0030%.

[0233] A preferred minimum limit for Mg content is 0.0001%, more preferably 0.0002%, and even more preferably 0.0003%.

[0234] A preferred maximum limit for Mg content is 0.0025%, more preferably 0.0020%, even more preferably 0.0015%, and even more preferably 0.0010%. Method for Measuring the Chemical Composition of Non-Oriented Electrical Steel Sheet

[0235] The chemical composition of the non-oriented electrical steel sheet of the present embodiment can be measured by means of a well-known composition analysis method according to JIS G0321: 2017. Specifically, a drill is used to collect a machined chip from the steel sheet. The collected machined chip is dissolved in acid to obtain a liquid solution. The liquid solution is subjected to ICP-AES (Inductively Coupled Plasma Atomic Emission Spectrometry) to perform the elemental analysis of the chemical composition. The C content and S content are determined by means of a well-known high-frequency combustion method (infrared combustion-absorption method). The N content is determined using a well-known inert gas fusion-thermal conductivity method. The O content is determined using a well-known inert gas fusion-infrared absorption method.

[0236] Note that the content of each element is considered a numerical value up to the least significant digit of the content of each element defined in this embodiment, obtained by rounding a fraction of the numerical value measured based on the significant digits defined in this embodiment. For example, the Si content in the steel sheet of this embodiment is defined as a numerical value up to the first decimal place. Therefore, the Si content is considered a numerical value up to the first decimal place, obtained by rounding the Petition 870250084752, dated 09 / 19 / 2025, page 44 / 111 38 / 86 second decimal place of the measured numerical value.

[0237] Similarly, for the content of each element other than the Si content in the steel sheet of the present embodiment, a value obtained by rounding a fraction of the numerical value of the measured value to the least significant digit defined in the present embodiment is considered as the content of the relevant element.

[0238] Note that the term rounding means rounding down if the fraction is less than 5 and rounding up if the fraction is 5 or more. (Characteristic 2) About Formula (1) and Formula (2)

[0239] The non-oriented electrical steel sheet of the present embodiment also satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percent is replaced by each element symbol in Formula (1) and Formula (2) and, if a corresponding element is not contained, 0 is replaced by the corresponding element symbol. Regarding Formula (1)

[0240] Formula (1) is a formula for sufficiently reducing the amount of dissolved C in the steel sheet, forming carbides or carbonitrides. The left side of Formula (1) is composed of elements that combine with C to form carbides or carbonitrides. When Formula (1) is satisfied, the amount of dissolved C is sufficiently reduced, since carbides or carbonitrides are formed in sufficient quantity. Regarding Formula (2)

[0241] Formula (2) is a formula for sufficiently reducing the amount of dissolved N in the steel sheet, forming nitrides or carbonitrides. The left side of Formula (2) is composed of elements Petition 870250084752, dated 09 / 19 / 2025, page 45 / 111 39 / 86 which combine with N to form nitrides or carbonitrides. When Formula (2) is satisfied, the amount of dissolved N is sufficiently reduced, since nitrides or carbonitrides are formed in sufficient quantity. (Characteristic 3) Tensile Strength TS

[0242] In the non-oriented electrical steel sheet of the present embodiment, the tensile strength TS is greater than 570 MPa. That is, the non-oriented electrical steel sheet of the present embodiment exhibits high strength.

[0243] A preferred minimum limit of the tensile strength TS of the non-oriented electrical steel sheet of the present embodiment is 575 MPa and, more preferably, is 580 MPa.

[0244] The maximum tensile strength limit TS is not particularly limited. However, in a case where Characteristics 1 and 2 are satisfied, the maximum tensile strength limit TS is, for example, 750 MPa. Method for Measuring the Stress-Strain Curve

[0245] The tensile strength (TS) of the non-oriented electrical steel sheet of the present embodiment is measured using the following method. A JIS No. 5 tensile test specimen, defined in JIS Z 2241: 2011, is taken from the non-oriented electrical steel sheet. The obtained tensile test specimen is used to perform a tensile test at normal ambient temperature according to JIS Z 2241: 2011 in order to obtain a stress-strain curve. The tensile strength (TS) (MPa) is determined based on the obtained stress-strain curve. (Characteristic 4) Regarding the degree of work hardening WH]

[0246] In the non-oriented electrical steel sheet of the present embodiment, furthermore, when the stress at 2.0% strain is expressed as Y2.0 (MPa) and the yield strength is expressed as YS (MPa), Petition 870250084752, dated 09 / 19 / 2025, page 46 / 111 40 / 86 the work hardening degree WH defined by Formula (3) is less than 15 MPa. WH = Y2,o-YS (3)

[0247] If dislocations multiply excessively during blanking, the possibility of dislocations to which dissolved C or dissolved N are attached increases. If dislocations to which dissolved C or dissolved N are attached increase, regions with a high density of interlocked dislocations will be formed locally. In this case, irregularities are likely to occur in a blanking-cut product after blanking, and sufficient dimensional accuracy will not be achieved.

[0248] The work hardening degree WH correlates with the dislocation density. If the work hardening degree WH is less than 15 MPa, the dislocation density is sufficiently suppressed during blanking. Therefore, the occurrence of dislocations in which dissolved C or dissolved N is fixed can be sufficiently suppressed. Consequently, the occurrence of irregularities attributable to blanking in the blanking cut product after blanking will be suppressed and sufficient dimensional accuracy will be obtained.

[0249] A preferred maximum limit of the work hardening degree WH is 14 MPa, more preferably it is 13 MPa, even more preferably it is 12 MPa, even more preferably it is 11 MPa and, even more preferably, it is 10 MPa.

[0250] The work hardening degree WH is preferably as low as possible. Considering industrial productivity, a preferable minimum limit for the work hardening degree WH is 2 MPa, more preferably 1 MPa and, even more preferably, 0 MPa. Essay to Evaluate the Degree of Work Hardening WH Petition 870250084752, dated 09 / 19 / 2025, page 47 / 111 41 / 86

[0251] The work hardening degree WH can be determined using the following method. A tensile test described above in the section [Method for Measuring the Stress-Strain Curve] is performed to obtain a stress-strain curve.

[0252] Figure 1 is a schematic diagram of an illustrative stress-strain curve. With reference to Figure 1, the maximum stress value when the strain is within a range of 0 to 0.2% plastic deformation is defined as the yield strength YS (MPa).

[0253] In Figure 1, when the strain is within a range L0 of 0 to 0.2% plastic strain, a maximum yield point P0 occurs on the stress-strain curve. Therefore, in a case where the stress-strain curve is a curve with a maximum yield point, as illustrated in Figure 1, the stress at the maximum yield point P0 is defined as the yield strength YS (MPa).

[0254] On the other hand, in a case where the stress-strain curve is a curve in which there is no maximum yield strength P0, as in the stress-strain curve illustrated in Figure 2, when the strain is within the range L0 from 0 to 0.2% plastic strain, the maximum stress value is at the 0.2% plastic strain position. Therefore, in this case, the 0.2% proof stress is defined as the yield strength YS (MPa).

[0255] Furthermore, with reference to Figure 1 and Figure 2, in the stress-strain curve, the stress at 2.0% strain is expressed as Y2,o(MPa).

[0256] Using the yield strength YS (MPa) and the stress Y2,o (MPa) obtained, the strain hardening value WH (MPa) is calculated by Formula (3). Note that, in a case where YS > Y2.o, WH is set to 0 (MPa). Petition 870250084752, dated 09 / 19 / 2025, page 48 / 111 42 / 86 (Characteristic 5) Regarding Average Grain Size D

[0257] In the non-oriented electrical steel sheet of the present embodiment, moreover, the average grain size D (μm) satisfies Formula (4) and the elongation due to elasticity is 0.5% or more: D < 80-Si x10 (4) where the Si content, in mass percentage in the chemical composition of the non-oriented electrical steel sheet, is replaced by Si in Formula (4).

[0258] Fn is defined as follows. Fn = 80-Si x10

[0259] If the average grain size D (μm) is smaller than Fn, the sources of dislocation generation during deformation can be increased and the sources of dislocation generation can be dispersed. In this case, dislocations will occur in a dispersed and non-local manner during the deformation of the steel sheet during blanking. Consequently, dislocation entanglement will be suppressed. As a result, the yield strength will easily become 0.5% or more, and the non-uniformity of deformation in the thickness direction during blanking can be reduced. As a result, the dimensional accuracy after blanking can be increased.

[0260] A preferred minimum limit of the average grain size D is μm, more preferably it is 15 μm and, even more preferably, it is 20 μm.

[0261] A preferred maximum limit for the average grain size D is 75-Si x10 (μm), more preferably 70-Si x10 (μm) and, even more preferably, 65-Si x10 (μm).

[0262] A preferred minimum limit of elongation elasticity is 0.6%, more preferably it is 0.7%, even more preferably it is 1.0% and, even more preferably, it is 1.5%. Petition 870250084752, dated 09 / 19 / 2025, p. 49 / 111 43 / 86

[0263] Although the maximum yield elongation limit is not particularly restricted, approximately 7.0% is the maximum limit. Method for Measuring Average Grain Size D

[0264] The average grain size D is determined using the following method. A cross-section (cross-section L) parallel to the elongation direction of the non-oriented electrical steel sheet lamination is adopted as the observation surface. The observation surface is mirror-polished and then chemically etched with a nital solution. The chemically etched observation surface is observed at 100x magnification using an optical microscope, and a photographic image of the observation field is generated. Using the photographic image, the average grain size D (μm) is determined by a method that calculates the number of grains within a rectangular region, which will be described later, according to JIS G 0551:2013 Steels - Micrographic Determination of Apparent Grain Size.

[0265] Specifically, in cross-section L, a rectangular region is drawn consisting only of recrystallized grains, excluding non-recrystallized regions, and which is surrounded by straight line segments parallel to the sheet thickness direction and the sheet surface direction (rolling elongation direction). The rectangular region is considered the field of observation. An area A of the rectangular region is defined as 0.5 mm² or more. If an area of ​​0.5 mm² or more cannot be protected with a rectangle, several rectangular regions are drawn so that the total area A of the rectangular regions is 0.5 mm² or more.

[0266] The number of grains in the rectangular region is counted. Specifically, the number of grains that exist within the rectangular region. Petition 870250084752, dated 09 / 19 / 2025, page 50 / 111 44 / 86 and that do not come into contact with any of the sides of the rectangular region is expressed as N1. The number of grains that intersect with any of the four sides of the rectangular region, excluding the four corners of the sides (the four vertices of the rectangle), is expressed as N2. The number of all rectangular regions that were drawn to ensure an area of ​​0.5 mm2 or more is expressed as N3. The average grain size D (μm) is calculated by Formula (I) using the total area A (mm2) of the rectangular region(s) and the number of grains N1 to N3. Mathematical Formula 1 Medium grain size D THE N2 Ξ N1 + Nr + N3 Method for Measuring Elasticity Stretch

[0267] The elongation is determined using the following method. A tensile test specimen is taken from the non-oriented electrical steel plate. A tensile test is performed at normal room temperature according to JIS Z 2241: 2011 and the elongation (%) is determined. A JIS No. 5 tensile test specimen is used as the tensile test specimen.

[0268] Note that in a case where the maximum yield point is not clearly visible, the elongation (%) is determined using the following method. Referring to Figure 3, on a stress-strain curve obtained from the tensile test, the yield strength YS (MPa) is determined based on the method described above in the section [Test to Evaluate the Degree of Work Hardening WH]. The strain value at the yield strength is determined. YS is expressed as ε1. On the stress-strain curve, starting from the strain value ε1, a maximum strain value ε2 is reached in a given area. Petition 870250084752, dated 09 / 19 / 2025, page 51 / 111 45 / 86 region where the stress is maintained within a yield strength range YS ±1.0% as strain increases is identified. The elongation at yield strength is determined by the following formula using ε1 and ε2. Elasticity stretch (%) = ε2 - ε1 Regarding the Advantageous Effects of the Non-Oriented Electrical Steel Sheet of the Present Embodiment

[0269] The non-oriented electrical steel sheet of the present embodiment satisfies Characteristic 1 to Characteristic 5. Therefore, in the non-oriented electrical steel sheet of the present embodiment, even if high strength and sufficient magnetic properties are obtained, excellent dimensional accuracy is obtained after cutting in blanking. Method for Producing Non-Oriented Electrical Steel Sheet

[0270] An example of a method for producing non-oriented electrical steel sheet of the present embodiment will be described below. The method for producing non-oriented electrical steel sheet of the present embodiment includes the following processes. (Process 1) Hot rolling process (Process 2) Hot rolled sheet annealing process (Process 3) Cold rolling process (Process 4) Final annealing process

[0271] Among processes 1 through 4 above, process 2 is optional. That is, process 2 does not need to be executed. Each process will be described below. (Process 1) Hot Rolling Process

[0272] In the hot rolling process, a plate is subjected to hot rolling to produce a hot-rolled steel sheet. The plate is produced by means of a well-known method. Petition 870250084752, dated 09 / 19 / 2025, p. 52 / 111 46 / 86 For example, the plate is produced through a continuous casting process.

[0273] The prepared plate is subjected to hot rolling. The various hot rolling conditions are not particularly limited. The heating temperature of the plate is, for example, 1100 to 1200°C. The finishing temperature of the rolling is, for example, 800 to 1100°C. The coiling temperature is, for example, 700 to 800°C. A hot-rolled steel sheet is produced by the above process. (Process 2) Hot Rolled Sheet Annealing Process

[0274] The hot rolled sheet annealing process is an optional process. That is, the hot rolled sheet annealing process may or may not be carried out. When carried out, in the hot rolled sheet annealing process, the hot rolled steel sheet is annealed. Hot rolled sheet annealing can be box annealing or continuous annealing. The annealing conditions in the hot rolled sheet annealing process are not particularly limited. In the case of box annealing, the annealing temperature is, for example, from 750 °C to 850 °C and the holding time at the annealing temperature is, for example, from one hour to 30 hours. In the case of continuous annealing, the annealing temperature is, for example, from 900 °C to 1000 °C and the holding time at the annealing temperature is, for example, from 1 second to 100 seconds.Note that, as needed, a well-known pickling treatment can be performed on the hot-rolled steel sheet before annealing in the hot-rolled sheet annealing process and / or on the hot-rolled steel sheet after annealing has been performed. (Process 3) Cold Rolling Process.

[0275] In the cold rolling process, the rolled steel sheet Petition 870250084752, dated 09 / 19 / 2025, page 53 / 111 47 / 86 hot-rolled steel sheet produced in the hot rolling process, or hot-rolled steel sheet after the annealing process, is subjected to cold rolling to produce a cold-rolled steel sheet. Cold rolling can be performed only once or several times. In the case of repeated cold rolling, intermediate annealing can be performed at a specific time after a cold rolling and before the next cold rolling. (Process 4) Final Annealing Process

[0276] Cold-rolled steel sheet produced by the cold rolling process is subjected to final annealing in a final annealing furnace. In final annealing, the finished cold-rolled steel sheet at the final sheet thickness is annealed to cause recrystallization and grain growth. In the final annealing process, conditions 1 to 5 below are satisfied. Condition 1

[0277] Anneal at a maximum attainable temperature T1 (°C) of 950°C or less. Condition 2

[0278] The stress TE applied to the cold-rolled steel sheet at the maximum temperature to be reached T1 (°C) must be from 2.0 to 10.0 MPa. Condition 3

[0279] The residence time t0 (seconds) from an annealing temperature T1 to 700°C in a heating zone, an immersion zone and a cooling zone of the final annealing furnace and the residence time t1 (seconds) from 700 to 500°C in the cooling zone must be defined to satisfy Formula (A) and Formula (B). t1-t0 > 0 (A) t1 / t0 < 3.0 (B) Petition 870250084752, dated 09 / 19 / 2025, p. 54 / 111 48 / 86 Condition 4

[0280] Furthermore, in one or more selected locations of the heating zone, the immersion zone and the cooling zone in a temperature range of 500°C or more in a furnace atmosphere of the final annealing furnace, the ratio of the partial pressure of water vapor PH20(atm) to the partial pressure of hydrogen Ph2 (atm) must be greater than 0.05 or the oxygen concentration must be greater than 0.010% by volume. Condition 5

[0281] A temperature gradient CG in the longitudinal direction of cold-rolled steel sheet in a cooling process must be 20°C / m or less.

[0282] Conditions 1 through 5 are described below. (Condition 1) Regarding the Maximum Temperature to be Reached T1

[0283] The maximum temperature to be reached T1 must be 950°C or less. If the maximum temperature to be reached T1 is greater than 950°C, carbide and nitride solubilization will occur in the steel sheet. As a result, the work hardening degree WH defined by Formula (3) will be 15 MPa or more. Therefore, the maximum temperature to be reached T1 is 950°C or less. It is sufficient that the minimum limit of the maximum temperature to be reached T1 is a well-known temperature. The minimum limit of the maximum temperature to be reached T1 is, for example, 800°C. (Condition 2) Regarding Voltage TE at the Maximum Temperature to be Reached T1

[0284] The stress TE applied to the cold-rolled steel sheet at the maximum temperature to be reached T1 must be from 2.0 to 10.0 MPa. Specifically, the stress TE must be applied in the direction of elongation of the rolling (longitudinal direction) of the cold-rolled steel sheet. Petition 870250084752, dated 09 / 19 / 2025, page 55 / 111 49 / 86

[0285] If the TE stress is less than 2.0 MPa, the sources of dislocation generation will not be sufficiently obtained in the steel plate. In this case, even if the electrically non-oriented steel plate satisfies Formula (4), the elongation due to yield will be less than 0.5%.

[0286] On the other hand, if the stress TE is greater than 10.0 MPa, residual deformation will occur in the steel plate. In this case, the work hardening degree WH will be 15 MPa or more. (Condition 3) Regarding the Length of Residence t0 and t1

[0287] In final annealing, the residence time t0 (seconds) from annealing temperature T1 to 700 °C in a heating zone, an immersion zone, and a cooling zone of the final annealing furnace and the residence time t1 (seconds) from 700 to 500 °C in the cooling zone must be defined to satisfy Formula (A) and Formula (B): t1-t0 > 0 (A) t1 / t0 < 3.0 (B) where the residence time t0 includes, in the heating, immersion, and cooling zones, the time required to reach the maximum temperature to be reached T1 from 700°C in the heating process, the retention time at the maximum temperature to be reached T1, and the time required to reach 700°C from the maximum temperature to be reached T1 in the cooling process. The residence time t1 corresponds to the time period in the range of 700 to 500°C in the cooling zone and does not include the time required to reach 700°C from 500°C in the heating process (heating zone).

[0288] In the temperature range between the annealing temperature At T1 and 700°C, carbides and nitrides dissolve easily, and dissolved C or dissolved N forms easily. On the other hand, the range of Petition 870250084752, dated 09 / 19 / 2025, p. 56 / 111 50 / 86 A temperature range of 700°C to 500°C is a temperature range in which carbides, carbonitrides, and nitrides are easily formed. Dissolved C or dissolved N binds to dislocations and inhibits their movement. If the number of dislocations whose movement is inhibited increases, dislocation entanglement will increase. Therefore, in the non-oriented electrical steel sheet of the present embodiment, dissolved C or dissolved N is reduced to a minimum.

[0289] FA is defined as follows. FA = t1-t0

[0290] FA corresponds to the left side of Formula (A). If FA is greater than 0, that is, if the residence time t1 is greater than the residence time t0, while suppressing the solubilization of carbides and nitrides formed before final annealing, the carbon and nitrogen that were dissolved can be fixed again as carbides, carbonitrides, and nitrides. Therefore, the dissolved C or dissolved N in the steel plate can be reduced. As a result, the work hardening degree WH can be less than 15 MPa.

[0291] FB is defined as follows. FB = t1 / t0

[0292] FB corresponds to the left side of Formula (B). If FB is greater than 3.0, the remaining dissolved C or dissolved N in the steel plate will bind to the dislocations and will not precipitate. In this case, since the dislocations will accumulate easily, the work hardening degree WH will increase. If FB is 3.0 or less, the work hardening degree WH can be sufficiently suppressed. (Condition 4) Regarding Oxygen Potential

[0293] In the final annealing, moreover, in one or more selected locations of the heating zone, the immersion zone and the cooling zone in a temperature range of 500°C or more in the atmosphere of the final annealing furnace, the ratio of the partial pressure of Petition 870250084752, dated 09 / 19 / 2025, page 57 / 111 51 / 86 water vapor pH20 (atm) for the partial pressure of hydrogen pH2 (atm) must be greater than 0.05 or the oxygen concentration must be greater than 0.010%.

[0294] The ratio between the partial pressure of water vapor Ph20 (atm) and the partial pressure of hydrogen Ph2 (atm) in the atmosphere of the final annealing furnace is defined as the oxygen potential. In one or more selected locations between the heating zone, the immersion zone, and the cooling zone within a temperature range of 500°C or more in the atmosphere of the final annealing furnace, if the oxygen potential is greater than 0.05 or if the oxygen concentration is greater than 0.010%, decarburization will be promoted in the steel plate during final annealing. In this case, the dissolved C in the steel plate can be sufficiently reduced. As a result, the work hardening degree WH can be less than 15 MPa. (Characteristic 5) Regarding the Temperature Gradient CG in the Longitudinal Direction of Cold-Rolled Steel Sheet in the Cooling Process

[0295] In the cooling process, the temperature gradient in the longitudinal direction (direction of elongation of the lamination) of the cold-rolled steel sheet until it reaches 500°C from the maximum temperature to be reached T1 is defined as CG (°C / m). The temperature gradient CG is determined based on the distance traveled by the steel sheet during the period until the temperature of the cold-rolled steel sheet reaches 500°C from the maximum temperature to be reached T1 and the temperature difference calculated by subtracting 500°C from the maximum temperature to be reached T1.

[0296] If the temperature gradient CG in the cooling process is greater than 20°C / m, residual deformation will occur in the steel plate due to thermal deformation. In this case, the work hardening degree WH will be 15 MPa or more. Therefore, the gradient Petition 870250084752, dated 09 / 19 / 2025, p. 58 / 111 52 / 86 of CG temperature should be 20 °C / m or less. Another Process

[0297] In the production method described above, a coating process can be carried out after final annealing. In the coating process, an insulating coating is applied to the surface of the non-oriented electrical steel sheet after final annealing. The type of insulating coating is not particularly limited. The insulating coating can be composed of organic or inorganic components.

[0298] The non-oriented electrical steel sheet of the present embodiment can be produced by means of the production method described above. Note that the method for producing the non-oriented electrical steel sheet of the present embodiment is not particularly limited, provided that the non-oriented electrical steel sheet meets Characteristic 1 to Characteristic 5. Regarding the Rotor Core

[0299] The rotor core of the present embodiment is produced using the non-oriented electrical steel sheet of the present embodiment as raw material.

[0300] Figure 4 is a plan view illustrating an example of rotor core 1. Referring to Figure 4, rotor core 1 includes a plurality of rotor core 2 raw materials. The rotor core 2 raw material is in the form of a sheet. More specifically, the rotor core 2 raw material is in the form of a disc. Rotor core 1 consists of a plurality of rotor core 2 raw materials stacked together.

[0301] The shape of the rotor core 2 raw material is not particularly limited, as long as it has the shape of a sheet. Figure 4 illustrates, as an example, a rotor core 2 raw material for a permanent magnet synchronous motor. However, as long as the rotor core 2 raw material has the shape of Petition 870250084752, dated 09 / 19 / 2025, p. 59 / 111 53 / 86 a sheet, the raw material of the rotor core 2 may have a different shape from that illustrated in Figure 4. For example, in the case where the motor is a reluctance motor, the raw material of the rotor core may have the shape of a sheet with a plurality of salient poles or it may have the shape of a sheet with a plurality of through holes that serve as flux barriers. Furthermore, in the case where the motor is an induction motor, the raw material of the rotor core 2 may have a plurality of through holes in which induced current paths made of copper or aluminum die casting or similar are provided.

[0302] As described above, the rotor core raw material is a raw product produced by blanking the non-oriented electrical steel sheet of the present embodiment. Therefore, the rotor core raw material 2 meets Characteristics 1 to 5 mentioned above.

[0303] Specifically, the raw material of rotor core 2 consists of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2) and, if a corresponding element is not contained, Petition 870250084752, dated 09 / 19 / 2025, pp. 60 / 111 54 / 86 is replaced by the symbol for the corresponding element.

[0304] In the raw material of rotor core 2, moreover, the tensile strength TS is greater than 570 MPa.

[0305] In the raw material of rotor core 2, moreover, when the stress at 2.0% strain is expressed as Y2,o (MPa) and the yield strength is expressed as YS (MPa), the work hardening degree WH defined by Formula (3) is less than 15 MPa. WH = Y2,o -YS (3)

[0306] In the raw material of rotor core 2, moreover, the average grain size D (μm) satisfies Formula (4) and the elongation of elasticity is 0.5% or more: D < 80-Si x10 (4) where the content of a corresponding element in mass percentage is replaced by the symbol of an element in Formula (4) and, if the corresponding element is not contained, 0 is replaced by the symbol of the corresponding element. Regarding the Stator Core

[0307] Note that a stator core can be produced using the non-oriented electrical steel sheet of the present embodiment as the raw material. Figure 5 is a plan view of a stator core 3. With reference to Figure 5, the stator core 3 includes a plurality of stator core 4 raw materials. The stator core 4 raw material has the form of an annular plate. The stator core 3 consists of a plurality of stator core 4 raw materials that are stacked together.

[0308] The stator core raw material 4 includes a plurality of toothed portions 41. The plurality of toothed portions 41 is positioned with a gap between the respective toothed portions 41 in the circumferential direction of the stator core raw material 4. Each of the toothed portions 41 extends in the radial direction of the material. Petition 870250084752, dated 09 / 19 / 2025, pp. 61 / 111 55 / 86 prime of stator core 4.

[0309] The raw material for stator core 4 is produced by cutting the non-oriented electrical steel sheet of the present embodiment and then performing stress-relieving annealing. Therefore, the raw material for stator core 4 meets Characteristic 1 and Characteristic 2 mentioned above.

[0310] Specifically, the raw material of stator core 4 consists of, in % by mass, Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010% and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and satisfies Formula (1) and Formula (2): Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 *750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 *1000 (2) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1) and Formula (2), and if a corresponding element is not contained,0 is replaced by the symbol of the corresponding element. Method for Measuring the Chemical Composition of Rotor Core Raw Material 2 and Stator Core Raw Material 4

[0311] The chemical composition of the rotor core raw material and the stator core raw material 4 can be measured based on the method described above in the section [Method for Measuring the Chemical Composition of Non-Oriented Electrical Steel Sheet]. Specifically, a drill is used to collect a machined chip from the raw material. Petition 870250084752, dated 09 / 19 / 2025, page 62 / 111 56 / 86 of rotor core 2 or stator core raw material 4. The collected machined chips are dissolved in acid to obtain a liquid solution. The liquid solution is subjected to ICP-AES to perform elemental analysis of the chemical composition. The C and S content are determined by a well-known high-frequency combustion method (combustion infrared absorption method). The N content is determined using a well-known inert gas fusion thermal conductivity method. The O content is determined using a well-known inert gas fusion infrared absorption method. Method for Measuring the Stress-Strain Curve of Rotor Core Raw Material 2

[0312] The tensile strength TS of the rotor core raw material is measured using the following method. A JIS No. 5 tensile test specimen, as defined in JIS Z 2241 (2011), is taken from the rotor core raw material 2. In a case where it is not possible to take a JIS No. 5 tensile test specimen due to the small size of the rotor core raw material 2, a reduced-scale test specimen of a JIS No. 5 tensile test specimen is taken from the rotor core raw material 2.

[0313] The tensile test specimen obtained is used to perform a tensile test at room temperature in accordance with JIS Z 2241:2011 in order to obtain a stress-strain curve. The tensile strength TS (MPa) is determined from the stress-strain curve obtained. Note that, in the case of performing the tensile test with a reduced-scale test specimen, the test must be performed based on the strain rate specified in Annex JB of the aforementioned standard. Test to Evaluate the Work Hardening Degree (WH) of the Raw Material for Rotor Core 2 Petition 870250084752, dated 09 / 19 / 2025, page 63 / 111 57 / 86

[0314] The work hardening degree WH of the rotor core 2 raw material is determined using the method described above in the section [Test to Evaluate the Work Hardening Degree WH]. At this point, the stress-strain curve obtained in the [Method for Measuring the Stress-Strain Curve of Rotor Core 2 Raw Material] mentioned earlier is used as the stress-strain curve. Method for Measuring the Average Grain Size D of Rotor Core Raw Material 2]

[0315] The average grain size D of the rotor core raw material 2 is determined using the method described above in the section [Method for Measuring Average Grain Size D]. Note that, in the rotor core raw material 2, a cross-section (cross-section L) parallel to the direction of lamination elongation is adopted as the observation surface. Method for Measuring the Elasticity Elongation of Rotor Core Raw Material 2

[0316] The elongation of the rotor core 2 raw material is determined using the following method. Specifically, a JIS No. 5 tensile test specimen is taken from the rotor core 2 raw material. A tensile test is performed at normal ambient temperature according to JIS Z 2241: 2011 to determine the elongation (%). Note that in a case where a JIS No. 5 tensile test specimen cannot be taken due to the small size of the rotor core 2 raw material, a reduced-scale test specimen of a JIS No. 5 tensile test specimen is taken from the rotor core 2 raw material. In the case of performing the tensile test with a reduced-scale test specimen, the test must be performed based on the strain rate specified in Annex JB of the aforementioned standard. Petition 870250084752, dated 09 / 19 / 2025, page 64 / 111 58 / 86

[0317] Note that, in a case where the maximum point of elasticity does not appear clearly, the elongation (%) is determined using the following method. Referring to Figure 3, in the stress-strain curve obtained from the tensile test, the yield strength YS (MPa) is determined based on the method described above in section [Test to Evaluate the Degree of Work Hardening WH of Rotor Core Raw Material 2]. The strain value at the yield strength YS is expressed as ε1. In the stress-strain curve from the strain value ε1 onwards, a maximum strain value ε2 is identified in a region where the stress is maintained within a range of the yield strength YS ±1.0% as the strain increases. The elongation is determined by the following formula using ε1 and ε2. Elasticity stretch (%) = ε2 - ε1 Method for Producing Rotor Core 1

[0318] Rotor core 1 is produced using the following method.

[0319] The raw materials for rotor core 2 are produced from non-oriented electrical steel sheet of the present embodiment by means of blanking. Specifically, the raw materials for rotor core 2 are cut by means of blanking. The blanking-cut raw materials for rotor core 2 are stacked to produce rotor core 1. Regarding the Engine

[0320] The motor of the present embodiment is equipped with the rotor core 1 described above. The motor is also equipped with a well-known stator core. Since the motor of the present embodiment is equipped with the rotor core of the present embodiment, high resistance and sufficient magnetic properties are obtained in the rotor core.

[0321] Note that the stator core 3 described above may be Petition 870250084752, dated 09 / 19 / 2025, p. 65 / 111 59 / 86 adopted as the stator core included in the motor core. The stator core 3 is produced by the following method. The raw material for stator core 4 is produced by blanking using non-oriented electrical steel sheet of the present embodiment as a raw material. A plurality of raw materials for stator core 4 are stacked to produce stator core 3.

[0322] The dimensional accuracy of the stator core 4 raw material produced by blanking using the non-oriented electrical steel sheet of the present embodiment as the raw material is high. Therefore, stator core 3 is superior in terms of dimensional accuracy compared with a stator core produced using a conventional non-oriented electrical steel sheet with a tensile strength greater than 570 MPa as a raw material. In the case of producing stator core 3 using the non-oriented electrical steel sheet of the present embodiment as the raw material, after the stator core 4 raw materials are stacked, stress-relief annealing is performed. Thus, the motor incorporating stator core 3 will have higher efficiency. EXAMPLE 1

[0323] Non-oriented electrical steel sheets with the chemical compositions shown in Table 1 (Table 1A to Table 1C) were produced using the following method. Table 1A Test number Chemical composition (unit is % by mass; the remainder is Fe and impurities) Si CNOPS Ti Mn Al 1 3.3 0.0018 0.0013 0.0155 0.011 0.0012 0.0011 1.1 0.700 2 3.5 0.0017 0.0018 0.0210 0.007 0.0008 0.0013 0.6 0.300 3 4.2 0.0011 0.0011 0.0131 0.011 0.0003 0.0052 0.5 0.004 Petition 870250084752, dated 09 / 19 / 2025, p. 66 / 111 60 / 86 4 3,6 0,0010 0,0012 0,0171 0,033 0,0027 0,0016 0,3 0,300 5 3,8 0,0018 0,0017 0,0022 0,010 0,0022 0,0013 0,2 0,355 6 3,4 0,0017 0,0018 0,0136 0,034 0,0047 0,0021 0,4 0,409 7 3,9 0,0022 0,0010 0,0367 0,011 0,0009 0,0017 0,2 0,848 8 4,0 0,0024 0,0021 0,0091 0,007 0,0039 0,0008 0,5 0,246 9 3,3 0,0012 0,0012 0,0194 0,061 0,0012 0,0016 0,6 1,450 10 3,5 0,0011 0,0018 0,0268 0,033 0,0013 0,0013 0,8 0,393 11 3,6 0,0010 0,0012 0,0250 0,015 0,0007 0,0014 0,2 0,307 12 4,1 0,0011 0,0010 0,0045 0,007 0,0007 0,0011 0,2 0,402 13 4,3 0,0010 0,0019 0,0143 0,039 0,0027 0,0009 0,5 0,203 14 3,6 0,0017 0,0013 0,0065 0,050 0,0005 0,0013 0,4 0,577 15 3,3 0,0019 0,0017 0,0055 0,026 0,0014 0,0021 1,1 0,307 16 3,5 0,0015 0,0012 0,0134 0,007 0,0017 0,0023 0,2 0,724 17 3,2 0,0018 0,0014 0,0068 0,010 0,0007 0,0011 0,4 1,113 18 3,4 0,0015 0,0022 0,0243 0,016 0,0029 0,0016 0,3 1,239 19 3,8 0,0011 0,0018 0,0181 0,043 0,0008 0,0025 0,2 0,310 20 3,6 0,0019 0,0013 0,0152 0,007 0,0037 0,0017 0,8 0,681 21 3,3 0,0016 0,0019 0.0110 0.013 0.0005 0.0011 1.3 0.551 22 3.5 0.0017 0.0021 0.0348 0.011 0.0014 0.0013 0.3 0.939 23 3.2 0.0018 0.0015 0.0083 0.012 0.0007 0.0014 0.6 0.827 24 3.4 0.0016 0.0016 0.0107 0.026 0.0021 0.0011 0.6 0.517 25 3.6 0.0019 0.0019 0.0208 0.013 0.0023 0.0016 0.4 0.447 26 3.3 0.0011 0.0017 0.0301 0.046 0.0013 0.0023 1.1 0.483 27 3.5 0.0017 0.0018 0.0200 0.011 0.0015 0.0006 0.4 0.570 28 3.8 0.0020 0.0021 0.0048 0.017 0.0011 0.0014 0.4 0.446 29 3.3 0.0017 0.0018 0.0357 0.072 0.0006 0.0020 0.7 0.639 30 3.6 0.0018 0.0022 0.0051 0.017 0.0016 0.0018 0.7 1.180 31 3.2 0.0019 0.0018 0.0077 0.083 0.0029 0.0007 1.6 0.410 32 3.7 0.0024 0.0010 0.0184 0.012 0.0013 0.0014 0.4 0.308 33 3.9 0.0012 0.0024 0.0301 0.014 0.0026 0.0006 1.2 0.314 34 3.8 0.0011 0.0023 0.0143 0.022 0.0003 0.0007 1.5 0.287 35 3.0 0.0014 0.0019 0.0360 0.008 0.0015 0.0022 0.3 0.789 Petition 870250084752, dated 09 / 19 / 2025, p. 67 / 111 61 / 86 36 2,9 0,0012 0,0017 0,0049 0,011 0,0020 0,0005 0,2 0,521 37 3,0 0,0016 0,0016 0,0025 0,013 0,0018 0,0013 1,5 1,214 38 3,0 0,0013 0,0017 0,0021 0,011 0,0014 0,0008 1,2 1,113 39 3,7 0,0021 0,0020 0,0084 0,014 0,0007 0,0021 1,1 0,433 40 3,9 0,0021 0,0017 0,0163 0,013 0,0006 0,0010 0,2 0,885 41 3,3 0,0015 0,0016 0,0024 0,010 0,0011 0,0008 0,5 0,311 42 3,5 0,0017 0,0015 0,0031 0,009 0,0013 0,0016 0,4 0,231 43 3,3 0,0018 0,0013 0,0022 0,013 0,0013 0,0011 0,5 0,224 44 3,4 0,0015 0,0017 0,0026 0,014 0,0015 0,0013 0,3 0,343 45 4,0 0,0022 0,0019 0,0381 0,011 0,0034 0,0006 0,2 0,301 46 3,6 0,0020 0,0016 0,0248 0,021 0,0004 0,0009 0,2 0,398 47 3,4 0,0017 0,0018 0,0023 0,011 0,0011 0,0017 0,5 0,413 48 3,6 0,0016 0,0016 0,0019 0,009 0,0016 0,0019 0,4 0,526 49 3,4 0,0018 0,0019 0,0192 0,016 0,0007 0,0006 0,7 0,462 50 3,8 0,0016 0,0020 0,0283 0,015 0,0007 0,0007 1,4 0,324 51 3,3 0,0017 0,0017 0,0016 0,001 0,0009 0,0013 0,3 0,379 52 3,5 0,0019 0,0018 0,0027 0,014 0,0007 0,0007 0,5 0,351 Table 1B Test number Chemical composition (unit is % by mass; the remainder is Fe and impurities) Zr Nb V Mo Cr La Ce B Zn Ga 1 - - - - 0.02 3 - - - - - 2 - - - 0.020 0.04 1 - - - 0.000 1 - 3 0.009 2 0.001 4 - 0.010 0.02 3 0.005 4 0.0056 - - - 4 0.009 5 - - - - - - - - - 5 - 0.002 1 - - - - - - - - Petition 870250084752, dated 09 / 19 / 2025, pp. 68 / 111 62 / 86 6 - - 0.002 3 - - - - - - - 7 - - - 0.084 - - - - - - 8 - - - - 1.43 3 - - - - - 9 - - - - - - - - - - 10 - - - - - 0.007 3 - - - - 11 - - - - - - 0.0064 - - - 12 - - - - - - - 0.00 07 - - 13 - - - - - - - - - - 14 - - - - - - - - - - 15 - - - - 0.05 2 - - - - - 16 - - - - - - - - - - 17 - - - 0.013 - - - - 0.0016 - 18 - - - - - - - - - 0.0032 19 - - - - - - - - - - 20 - - - - - - - - - - 21 - - - - - - - - - - 22 - - - - - - - - - - 23 - - - - - - - - - - 24 0.0013 - - - 0.031 - - 0.000 2 - - 25 - - - - - 0.0023 0.0021 - 0.0003 0.0013 26 0.0034 0.0014 0.0011 0.015 0.043 - 0.0034 - - - 27 - - - - - - - - - - 28 0.0032 0.0013 - 0.024 0.130 - - - - - 29 - - - 0.013 0.032 - - 0.000 2 - - 30 - - - - - - - - 0.0007 0.0005 Petition 870250084752, dated 09 / 19 / 2025, pp. 69 / 111 63 / 86 31 - - - - - - - - - - 32 - - - - - - - - - - 33 - - - - - - - - - - 34 - - - - - - - - - - 35 - - - - - - - - - - 36 0.0013 - - 0.012 0.037 - - - - 0.0014 37 - - - - - - - - - - 38 - - - 0.011 0.023 - - - - - 39 - - - - - - - - - - 40 - - - - - 0.0026 0.0024 - - - 41 - - - 0.005 0.036 - - - - - 42 - - - - 0.036 - - - - - 43 - - - 0.007 - - - - - - 44 - - - 0.011 0.031 - - - - - 45 - - - - - - - - - - 46 - 0.0011 - 0.012 - - - - 0.0008 - 47 - - - - - - - - - - 48 - - - - 0.041 - - - - - 49 - - - - - - - - - - 50 - - 0.0013 - - - - 0.0005 - 0.0011 51 - - - 0.007 0.038 - - - - - 52 - - - - 0.029 - - - - - Table 1C Test number Chemical composition (unit is % by mass; the remainder is Fe and impurities) Ge As Ni Cu Sn Sb Ca Nd Mg Formula (1) Formula (2) 1 - - - - 0.01 1 - - - - TT 2 - 0.003 0 0.02 0 0.06 0 0.00 7 - 0.000 5 - 0.000 8 TT Petition 870250084752, dated 09 / 19 / 2025, pp. 70 / 111 64 / 86 3 - 0,001 0 0,02 0 0,06 0 0,01 3 - 0,000 5 - 0,000 6 T T 4 - - - - - - - - - T T 5 - - - - - - - - - T T 6 - - - - - - - - - T T 7 - - - - - - - - - T T 8 - - - - - - - - - T T 9 - - - - - - - - - T T 10 - - - - - - - - - T T 11 - - - - - - - - - T T 12 - - - - - - - - - T T 13 - - - - - - - - 0,002 4 T T 14 - - - - - - 0,003 5 - - T T 15 - - 0,23 6 - - - - - - T T 16 - - - 0,142 - - - - - T T 17 - - - - - - - - - T T 18 - - - - - - - - - T T 19 0,0 035 - - - - - - - - T T 20 - 0,005 9 - - - - - - - T T 21 - - - - 0,11 0 - - - - T T 22 - - - - - 0,06 3 - - - T T 23 - - - - - - - 0,000 6 - T T 24 - 0,002 3 - 0,03 1 0,01 1 - - - - T T Petição 870250084752, de 19 / 09 / 2025, pág. 71 / 111 65 / 86 25 0,0 011 0,002 4 0,03 1 0,04 3 0,02 1 - 0,001 1 0,000 8 0,000 5 T T 26 - - - - - - - 0,000 5 - T T 27 - - - - - 0,01 3 - - - T T 28 - - - - - - - - - T T 29 - 0,002 7 - 0,03 6 0,01 3 - 0,002 3 - - T T 30 - - 0,02 6 - - - - - 0,000 8 T T 31 - - - - - - - - - F T 32 - - - - - - - - - F T 33 - - - - - - - - - T F 34 - - - - - - - - - T F 35 - - - - - - - - - T T 36 - 0,002 6 - - 0,01 4 - - - - T T 37 - - - - - - - - - T T 38 - - 0,02 7 0,04 3 0,01 2 - 0,001 4 - - T T 39 - - - - - - - - - T T 40 - - - - 0,02 3 - 0,001 3 - - T T 41 - - - 0,03 6 - - - - - T T 42 - 0,002 6 - - 0,02 1 - - - - T T 43 - - - 0,03 4 0,02 2 - - - 0,000 7 T T 44 - - - - - - - - - T T 45 - - - - - - - - - T T Petição 870250084752, de 19 / 09 / 2025, pág. 72 / 111 66 / 86 46 0.0 014 0.002 1 0.04 1 - - - - 0.000 8 0.000 8 TT 47 - - - - 0.02 6 - - - - TT 48 - 0.002 3 - 0.03 9 - - - - 0.000 5 TT 49 - - - - - - - - - TT 50 - - - 0.03 7 0.02 3 0.01 1 - - - TT 51 - - - 0.02 8 0.02 7 - - - - TT 52 - 0.002 7 - - - - - - 0.000 6 TT

[0324] Note that, in the Formula (1) column of Table 1C, T means that the chemical composition satisfies Formula (1) and F means that the chemical composition does not satisfy Formula (1). In the Formula (2) column, T means that the chemical composition satisfies Formula (2) and F means that the chemical composition does not satisfy Formula (2).

[0325] Slabs (cast pieces) were subjected to hot rolling to produce hot-rolled steel sheets with a thickness of 2.0 mm. The slab heating temperature was 1100 to 1200°C. The finishing temperature of the rolling was 800 to 1100°C. The coiling temperature was 700 to 800°C. Each hot-rolled steel sheet was subjected to continuous annealing, in which the hot-rolled steel sheet was held at 1000°C for 60 seconds. Each steel sheet after annealing was subjected to cold rolling to produce a cold-rolled steel sheet with a thickness of 0.25 mm.

[0326] Each cold-rolled steel sheet produced was subjected to final annealing. The maximum temperature to be reached T1 (°C), the stress TE (MPa), the residence time t0 (s) and the residence time Petition 870250084752, dated 09 / 19 / 2025, p. 73 / 111 67 / 86 t1 (s), FA, FB, the oxygen potential Ph2o / Ph2, the oxygen concentration (%) and the temperature gradient CG (°C / m) at the final annealing are shown in Table 2. A non-oriented electrical steel sheet of each test number was produced using the above production process. Table 2 Test number Final Annealing Process Condition 1 Condition 2 Condition 3 Condition 4 Condition 5 Maximum temperature to be reached T1 (°C) TE (MPa) Residence time t0 (s) Residence time t1 (s) FA (t1 - t0) FB (t1 / t0) PH20 / PH2 Oxygen concentration (%) Temperature gradient CG (°C / m) 1 820 2.5 48 50 2 1.0 5.12 0.001 13 2 820 2.5 17 27 10 1.6 0.32 0.001 15 3 850 2.5 43 51 8 1.2 0.01 0.015 10 4 820 2.5 23 26 3 1.1 0.13 0.001 11 5 830 2.5 27 29 2 1.1 0.09 0.001 12 6 860 2.5 21 24 3 1.1 0.11 0.001 14 7 850 2.5 19 26 7 1.4 0.13 0.001 9 8 870 2.5 23 27 4 1.2 0.15 0.001 10 9 830 2.5 24 27 3 1.1 0.16 0.001 16 10 810 2.5 37 47 10 1.3 0.30 0.001 13 11 780 7.0 32 43 11 1.3 0.20 0.001 11 12 890 3.0 24 29 5 1.2 0.25 0.001 14 13 890 3.0 23 27 4 1.2 0.16 0.001 10 14 880 3.0 25 56 31 2.2 0.13 0.001 11 15 810 3.0 21 28 7 1.3 0.09 0.001 13 16 800 3.0 44 51 7 1.2 0.24 0.001 11 17 790 3.0 27 29 2 1.1 0.01 0.016 11 Petition 870250084752, dated 09 / 19 / 2025, pp. 74 / 111 68 / 86 18 830 3,0 25 27 2 1,1 0,13 0,001 13 19 850 3,0 26 53 27 2,0 0,20 0,001 9 20 840 3,0 22 26 4 1,2 0,46 0,001 10 21 780 8,0 15 29 14 1,9 0,01 0,017 10 22 920 3,0 26 29 3 1,1 0,16 0,001 13 23 800 2,5 18 27 9 1,5 0,06 0,023 11 24 810 2,5 17 28 11 1,6 0,13 0,001 10 25 830 2,5 21 26 5 1,2 0,25 0,001 18 26 840 2,5 18 29 11 1,6 0,09 0,001 13 27 810 2,5 48 53 5 1,1 0,24 0,001 11 28 910 2,5 24 26 2 1,1 0,17 0,001 10 29 790 2,5 27 29 2 1,1 0,11 0,001 11 30 870 2,5 17 27 10 1,6 0,26 0,001 9 31 830 2,5 19 26 7 1,4 0,36 0,001 9 32 850 3,0 23 27 4 1,2 0,25 0,001 11 33 860 3,0 22 26 4 1,2 0,68 0,001 10 34 820 3,0 24 28 4 1,2 0,82 0,001 11 35 830 3,0 23 27 4 1,2 0,11 0,001 10 36 890 3,0 22 26 4 1,2 0,13 0,001 13 37 860 3,0 24 28 4 1,2 0,25 0,001 12 38 870 3,0 13 27 14 2,1 0,09 0,001 13 39 960 2,5 26 27 1 1,0 0,16 0,001 11 40 970 2,5 21 29 8 1,4 0,20 0,001 10 41 800 1,5 24 27 3 1,1 0,18 0,001 9 42 820 1,5 21 29 8 1,4 0,16 0,001 11 43 780 11,0 19 23 4 1,2 0,24 0,001 13 44 830 11,0 23 26 3 1,1 0,22 0,001 12 45 860 2.5 29 18 -11 0.6 0.30 0.001 11 46 830 2.5 32 28 -4 0.9 0.24 0.001 10 47 820 2.5 26 81 55 3.1 0.17 0.001 9 48 850 2.5 19 61 42 3.2 0.24 0.001 13 49 820 3.0 22 30 8 1.4 0.00 0.001 8 Petition 870250084752, dated 09 / 19 / 2025, pp. 75 / 111 69 / 86 50 840 3.0 17 29 12 1.7 0.00 0.001 10 51 790 3.0 23 34 11 1.5 0.26 0.001 21 52 810 3.0 22 32 10 1.5 0.36 0.001 23 Assessment Essays

[0327] The non-oriented electrical steel sheet from each test number was subjected to the following evaluation tests. (Test 1) Test to measure chemical composition (Test 2) Test to measure tensile strength TS (Test 3) Test to evaluate the degree of work hardening WH (Test 4) Test to measure average grain size D (Test 5) Test to measure elongation (Test 6) Test to evaluate magnetic properties (Test 7) ​​Test to evaluate dimensional accuracy after blanking

[0328] Trials 1 through 7 are described below. (Essay 1) Essay to Measure Chemical Composition

[0329] The chemical composition of the non-oriented electrical steel sheet for each test number was determined according to the method described above in the section [Method for Measuring the Chemical Composition of Non-Oriented Electrical Steel Sheet]. The chemical composition of the non-oriented electrical steel sheet for each test number determined as a result is shown in Table 1 (Table 1A to Table 1C). (Test 2) Test to Measure Tensile Strength TS

[0330] The tensile strength TS (MPa) of the non-oriented electrical steel sheet from each test was determined according to the method described above in the section [Method for Measuring the Stress-Strain Curve]. The determined tensile strength TS (MPa) is shown in Table 3. Petition 870250084752, dated 09 / 19 / 2025, pp. 76 / 111 Table 3 Test number Tensile strength TS (MPa) Work hardening degree WH (MPa) Average grain size D (μm) 80- Six10 Formula (4) Elastic elongation (%) Magnetic properties Blanking flatness (μm) Observations Magnetic flux density B50 (T) Iron loss W5 / 1000 (W / kg) Iron loss deterioration degree ΔW5 / 1000 (W / kg) Shearing Electrical discharge machining 1 613 1 20 47 T 2.5 1.67 16.6 16.3 0.3 12 Example of the invention 2 598 0 22 45 T 4.5 1.68 16.4 16.3 0.1 11 Example of the invention 3 649 7 27 Example of the invention 4: 605 1 24 44 T 2.1 1.68 16.2 15.9 0.3 Example of the invention 5: 619 2 25 42 T 1.6 1.68 16.0 15.6 0.4 Example of the invention 6: 581 3 29 46 T 1.5 1.68 16.0 15.4 0.6 Example of the invention 7: 651 3 27 41 T 1.5 1.66 15.3 14.8 0.5 Example of the invention 8: 626 5 34 40 T 1.1 1.60 15.2 14.4 0.8 17 Example of the invention 9 644 2 23 47 T 2.1 1.65 15.7 15.3 0.4 13 Example of the invention 10 618 0 21 45 T 2.4 1.68 16.4 16.3 0.1 11 Example of the invention 11 610 0 20 44 T 2.1 1.69 17.0 16.9 0.1 10 Example of the invention, Petition 870250084752, dated 09 / 19 / 2025, p. 77 / 111 70 / 86 12 635 10 37 39 T 0.7 1.66 15.6 14.1 1.5 19 Example of the invention 13 664 7 36 37 T 1.0 1.65 15.0 13.9 1.1 18 Example of the invention 14 601 9 41 44 T 0.7 1.67 15.5 14.2 1.3 18 Example of the invention 15 595 2 21 47 T 2.1 1.68 16.9 16.4 0.5 13 Example of the invention 16 616 1 20 45 T 2.2 1.68 16.8 16.6 0.2 13 Example of the invention 17 612 0 Example of the invention: 18 48 T 2.5 1.67 17.0 16.9 0.1 11 Example of the invention: 18 629 1 22 46 T 2.1 1.66 16.0 15.8 0.2 12 Example of the invention: 19 622 3 27 42 T 1.7 1.68 15.9 15.4 0.5 14 Example of the invention: 20 627 2 24 44 T 1.8 1.66 15.7 15.4 0.3 14 Example of the invention: 21 616 0 18 47 T 2.8 1.67 16.9 16.8 0.1 13 Example of the invention: 22 591 12 43 45 T 0.7 1.66 15.6 13.9 1.7 16 Example of the invention 23 594 1 21 48 T 1.9 1.68 16.6 16.3 0.3 12 Example of the invention 24 603 1 22 46 T 1.9 1.68 16.5 16.2 0.3 12 Example of the invention 25 606 2 25 44 T 1.8 1.68 16.0 15.6 0.4 14 Example of the invention 26 595 3 27 47 T 1.6 1.67 15.8 15.2 0.4 16 Example of the invention 27 607 1 23 45 T 1.9 1.68 16.3 16.0 0,Example of the Invention 28 607 10 40 42 T 0.8 1.66 15.6 14.1 1.5 Example of the Invention 29 618 1 20 47 T 1.9 1.68 16.8 16.5 0.3 Example of the Invention 30 636 7 33 44 T 1.5 1.65 15.0 14.0 1.0 Example of the Invention 31 604 16 26 48 T 0.4 1.67 17.7 15.2 2.5 Comparative Example 32 610 17 25 43 T 0.3 1.68 18.4 15.6 2.8 Example Comparative, Petition 870250084752, dated 09 / 19 / 2025, pp. 78 / 111 71 / 86 33 645 17 28 41 T 0.3 1.66 17.2 14.7 2.5 35 Comparative Example 34 654 18 22 42 T 0.3 1.66 18.5 15.6 2.9 40 Comparative Example 35 558 17 23 50 T 2.0 1.69 19.2 16.3 2.9 13 Comparative Example 36 513 16 34 51 T 1.5 1.70 18.4 15.8 2.6 19 Comparative Example 37 595 17 28 50 T 1.2 1.65 17.2 14.6 2.6 31 Comparative Example 38 581 16 30 50 T 1.2 1.66 17.1 14.7 2.4 30 Comparative Example 39 590 17 67 43 F 0.1 1.65 15.3 13.0 2.3 34 Comparative Example 40 611 18 77 41 F 0.0 1.64 15.1 12.8 2.3 28 Comparative Example 41 576 13 22 47 T 0.3 1.69 19.3 16.6 2.7 27 Comparative Example 42 585 10 25 45 T 0.4 1.69 18.8 16.0 2.8 28 Comparative Example 43 579 17 19 47 T 1.1 1.70 20.1 17.2 2.8 33 Comparative Example 44 575 17 26 46 T 0.9 1.69 18.6 15.9 2.8 32 Comparative Example 45 634 17 28 40 T 1.0 1.67 17.7 15.1 2.6 34 Comparative Example 46 601 16 26 44 T 1.1 1.68 18.3 15.7 2.6 36 Comparative Example 47 585 16 25 46 T 1.2 1.68 18.5 15.9 2.6 34 Comparative Example 48 600 17 30 44 T 1.1 1.67 17.6 15.0 2,Example 6 35 Comparative Example 49 598 17 23 46 T 1.0 1.68 18.9 16.1 2.8 28 Example Comparative Example 50 638 17 28 42 T 1.0 1.66 17.1 14.6 2.5 30 Example Comparative Example 51 576 16 21 47 T 1.2 1.69 19.7 16.9 2.8 26 Example Comparative Example 52 598 18 23 45 T 1.3 1.68 19.0 16.1 3.0 30 Example Comparative, 72 / 86 Petition 870250084752, dated 09 / 19 / 2025, pp. 79 / 111 73 / 86 (Test 3) Test to Evaluate the Degree of Work Hardening WH

[0331] The degree of work hardening WH (MPa) of the non-oriented electrical steel sheet for each test number was determined according to the method described above in the section [Test to Evaluate the Degree of Work Hardening WH]. The determined degree of work hardening WH (MPa) is shown in Table 3. (Test 4) Test to Measure Average Grain Size D

[0332] The average grain size D (μm) of the non-oriented electrical steel sheet from each test number was determined according to the method described above in the section [Method for Measuring Average Grain Size D]. The average grain size D determined is shown in Table 3. (Test 5) Test to Measure Elasticity Elongation

[0333] The elongation (%) of the non-oriented electrical steel sheet from each test number was determined according to the method described above in the section [Method for Measuring Elongation]. The elongation (%) determined is shown in Table 3. Note that the value of Fn is shown in the 80-Si x10 column of Table 3. Furthermore, in the Formula (4) column of Table 3, T means that Formula (4) was met and F means that Formula (4) was not met. (Test 6) Test to Evaluate Magnetic Properties

[0334] Magnetic flux density B50 (T) and iron loss W5 / 1000 (W / kg) were determined using the following methods. Test to Evaluate Magnetic Flux Density B50

[0335] In the non-oriented electrical steel sheet of each test number, the magnetic flux density B50(l) in the rolling elongation direction (L direction) and the magnetic flux density Bõo(c) in the direction perpendicular to the rolling elongation direction (C direction) were measured. Specifically, according to JIS C standard Petition 870250084752, dated 09 / 19 / 2025, pages 80 / 111 74 / 86 2550-1: 2011, specimens for the Epstein test were cut in the L direction and the C direction from the non-oriented electrical steel sheet of each test number. The cut specimens for the Epstein test were subjected to a test method for a strip and sheet of electrical steel according to JIS C standards 2550-1: 2011 and 2550-3: 2011, and the magnetic flux densities B50(L) (T) and B50(C) (T) at 5000 A / m in the L and C directions were measured. The arithmetic mean value of the magnetic flux density B50(L) (T) in the L direction and the magnetic flux density B50(C) in the C direction was defined as the magnetic flux density B50(T). The determined magnetic flux density B50(T) is shown in Table 3. Iron Loss Assessment Test W5 / 1000

[0336] The specimens for the Epstein test were prepared in a similar manner to the test for evaluating the B50 magnetic flux density described above. Note that the specimens for the Epstein test were prepared by cutting in two ways: shearing with a defined clearance of 20 μm and electrical discharge machining. In other words, two types of specimens for the Epstein test were prepared for each test number: one shear-cut specimen aimed at forming a blanking cut; and one Epstein test specimen cut by electrical discharge machining.Each specimen for the Epstein test was subjected to a test method for an electrical steel strip and sheet according to JIS C 2550-1: 2011 and 2550-3: 2011 standards, and an iron loss of W5 / 1000(l) (W / kg) and an iron loss of W5 / 1000(C) (W / kg) at 0.5 T at 1000 Hz in the L direction (rolling elongation direction) and in the C direction (direction perpendicular to the rolling elongation direction) were measured. The arithmetic mean value of the iron loss W5 / 1000(l) in the L direction (rolling elongation direction) was calculated. Petition 870250084752, dated 09 / 19 / 2025, pp. 81 / 111 75 / 86 nation) and the iron loss W5 / 1000(c) (W / kg) in the C direction (direction perpendicular to the rolling elongation direction) was defined as the iron loss W5 / 1000 (W / kg). The iron loss W5 / 1000 (W / kg) in the Epstein test specimen obtained by shear cutting is shown in the Shear Cutting column of the Iron Loss W5 / 1000 (W / kg) column in Table 3. The iron loss W5 / 1000 (W / kg) in the Epstein test specimen obtained by electrical discharge machining is shown in the Electrical Discharge Machining column of the Iron Loss W5 / 1000 (W / kg) column in Table 3. A value obtained by subtracting the iron loss W5 / 1000 (W / kg) in electrical discharge machining from the iron loss W5 / 1000 (W / kg) in shear cutting was defined as the degree of deterioration due to iron loss ΔW5 / 1000 (W / kg). The degree of deterioration due to iron loss ΔW5 / 1000 (W / kg) is shown in Table 3. (Test 7) ​​Test to Evaluate Dimensional Accuracy After Cutting in Blanking

[0337] The dimensional accuracy after blanking of the non-oriented electrical steel sheet for each test number was evaluated using the following test. A ring-shaped sample (blanked product) with an inner diameter of 90 mm and an outer diameter of 100 mm was prepared by cutting the ring-shaped sample from the non-oriented electrical steel sheet for each test number using a blanking die in which the clearance was set to 8% of the sheet thickness. Furthermore, the prepared ring-shaped sample was cut in 45° increments around the normal line of the non-oriented electrical steel sheet from the rolling elongation direction of the non-oriented electrical steel sheet to make eight test specimens. Each test specimen was embedded in resin and the cut surface was polished to remove 1 mm or more of the same to eliminate the influence of the deformation that occurred. Petition 870250084752, dated 09 / 19 / 2025, p. 82 / 111 76 / 86 during cutting. After polishing, the cut surface near the blanking end face on the inner peripheral surface side and the cut surface near the blanking end face on the outer peripheral surface side were observed using an optical microscope at 100x magnification. As illustrated in Figure 6, a line segment 20 connecting a point P1 where the cut surface changed from a shear slope face 10 to a blanking end face 11 and a burr tip P2 of the blanking end face 11 was drawn. A line segment 21 that was parallel to line segment 20 and tangent to the blanking end face 11 projecting from line segment 20 was drawn. The distance d between line segment 20 and line segment 21 was determined.The arithmetic mean of the distances d determined for the eight specimens for testing (a total of 16 distances d for the inner peripheral surface side and the outer peripheral surface side, consisting of eight distances d on the cut surfaces near the blanking end face on the inner peripheral surface side and eight distances d on the cut surfaces near the blanking end face on the outer peripheral surface side) was defined as the blanking cut flatness (pm). The determined blanking cut flatness is shown in the Blanking Cut Flatness (pm) column in Table 3. Evaluation Results

[0338] With reference to Tables 1 to Table 3, in Tests No. 1 to 30, Characteristics 1 to 5 were satisfied. Therefore, in the non-oriented electrical steel sheets of these test numbers, the magnetic flux density B50 was 1.60 T or more and the iron loss deterioration degree AW5 / 1000, calculated by subtracting the Petition 870250084752, dated 09 / 19 / 2025, page 83 / 111 77 / 86 iron loss W5 / 1000 in shear cutting, iron loss W5 / 1000 in electrical discharge machining was 2.0 or less, and thus excellent magnetic properties (magnetic flux density and iron loss) were obtained. Furthermore, the blanking flatness was 25 μm or less, and therefore these test numbers exhibited excellent dimensional accuracy after blanking.

[0339] On the other hand, in Tests Nos. 31 to 34, Formula (1) or Formula (2) was not satisfied. Therefore, the flatness of the blanking cut was greater than 25 µm and sufficient dimensional accuracy was not obtained during the blanking cut. Furthermore, the degree of deterioration due to iron loss ΔW5 / 1000 was greater than 2.0 and thus excellent magnetic properties were not obtained.

[0340] In tests No. 35 and 36, the Si content was very low. Therefore, the tensile strength (TS) was very low. In addition, the work hardening degree (WH) was 15 MPa or more. As a result, the iron loss deterioration degree ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0341] In tests No. 37 and 38, the Si content was very low. Therefore, the work hardening degree WH was 15 MPa or more. As a result, the blanking flatness was greater than 25 µm and sufficient dimensional accuracy was not obtained during blanking. Furthermore, the iron loss deterioration degree ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0342] In tests No. 39 and 40, condition 1 was not met in the final annealing process. Therefore, the work hardening degree WH was 15 MPa or more. In addition, Formula (4) was not met and the elongation was also less than 0.5%. As a result, the flatness of cut in blanking was greater Petition 870250084752, dated 09 / 19 / 2025, page 84 / 111 78 / 86 than 25 pm and sufficient dimensional accuracy was not obtained during blanking. Furthermore, the degree of deterioration due to iron loss ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0343] In tests No. 41 and 42, the TE stress at the maximum temperature to be reached T1 was very low. Therefore, the elongation was less than 0.5%. As a result, the flatness of the blanking cut was greater than 25 µm and sufficient dimensional accuracy was not obtained during the blanking cut. Furthermore, the degree of deterioration due to iron loss ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0344] In tests No. 43 and 44, the stress TE at the maximum temperature to be reached T1 was very high. Therefore, the work hardening WH was 15 MPa or more. As a result, the flatness of the blanking cut was greater than 25 µm and sufficient dimensional accuracy was not obtained during the blanking cut. Furthermore, the iron loss deterioration ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0345] In tests No. 45 and 46, FA did not meet Formula (A) in the final annealing process. Therefore, the work hardening degree WH was 15 MPa or more. As a result, the blanking cut flatness was greater than 25 µm and sufficient dimensional accuracy was not obtained during blanking. Furthermore, the iron loss deterioration degree ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0346] In trials No. 47 and 48, the FB did not meet Formula (B). Therefore, the work hardening degree WH was 15 MPa or more. As a result, the flatness of the blanking cut was greater than 25 µm and sufficient dimensional accuracy was not obtained during the blanking cut. Furthermore, the degree of deterioration due to loss of... Petition 870250084752, dated 09 / 19 / 2025, page 85 / 111 79 / 86 iron ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0347] In tests No. 49 and 50, condition 4 was not satisfied in the final annealing process. Therefore, the work hardening degree WH was 15 MPa or more. As a result, the blanking flatness was greater than 25 μm and sufficient dimensional accuracy was not obtained during blanking. Furthermore, the iron loss deterioration degree ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained.

[0348] In tests No. 51 and 52, the temperature gradient CG was very large. Therefore, the work hardening degree WH was 15 MPa or more. As a result, the flatness of the blanking cut was greater than 25 μm and sufficient dimensional accuracy was not obtained during blanking. Furthermore, the iron loss deterioration degree ΔW5 / 1000 was greater than 2.0, and thus excellent magnetic properties were not obtained. EXAMPLE 2

[0349] Rotor cores with the shape illustrated in Figure 4 were produced using the non-oriented electrical steel sheets from Tests Nos. 1 to 30 of Example 1.

[0350] Specifically, the non-oriented electrical steel sheet from each test number was subjected to blanking. In the blanking process, a rotor core feedstock was prepared by cutting the non-oriented electrical steel sheet using a blanking die with the clearance set to 8% of the sheet thickness. A plurality of rotor core feedstocks were stacked to form the rotor core. The diameter of the rotor core feedstock was 70 mm.

[0351] The rotor core of each test number was subjected to the following evaluation tests. Petition 870250084752, dated 09 / 19 / 2025, page 86 / 111 80 / 86 (Test 1) Test to measure tensile strength TS (Test 2) Test to evaluate the degree of work hardening WH (Test 3) Test to measure the average grain size D (Test 4) Test to measure elongation (Test 5) Test to evaluate magnetic properties (Test 6) Test to evaluate dimensional accuracy after cutting in blanking

[0352] Trials 1 through 6 are described below. (Test 1) Test to Measure Tensile Strength TS

[0353] The rotor core raw material was separated from the rotor core. The tensile strength TS (MPa) of the rotor core raw material was determined according to the method described above in section [Method for Measuring the Stress-Strain Curve of Rotor Core Raw Material 2]. Note that the size of the specimen for tensile testing taken from the rotor core raw material was as follows: the width of the parallel portion was 2.50 mm, the reference length was 5.00 mm, the thickness was 0.25 mm, and the total length was 25 mm. The tensile strength TS (MPa) of the rotor core raw material is shown in Table 4. (Test 2) Test to Evaluate the Work Hardening Degree WH

[0354] The work hardening degree WH of the rotor core raw material was determined according to the method described above in section [Test to Evaluate the Work Hardening Degree WH of the Rotor Core Raw Material 2]. The work hardening degree WH (MPa) determined for the rotor core raw material is shown in Table 4. (Test 3) Test to Measure Average Grain Size D

[0355] The rotor core raw material was separated from the rotor core. The average grain size D (μm) of the core raw material Petition 870250084752, dated 09 / 19 / 2025, page 87 / 111 81 / 86 of rotor was determined according to the method described above in section [Method for Measuring the Average Grain Size D of Rotor Core Raw Material 2]. The average grain size D (μm) determined from the rotor core raw material is shown in Table 4. (Test 4) Test to Measure Elasticity Elongation

[0356] The rotor core raw material was separated from the rotor core. The elastic elongation (%) of the rotor core raw material was determined according to the method described above in section [Method for Measuring the Elastic Elongation of Rotor Core Raw Material 2]. Note that the size of the tensile test specimen taken from the rotor core raw material was as follows: the width of the parallel portion was 2.50 mm, the reference length was 5.00 mm, the thickness was 0.25 mm, and the total length was 25 mm. The elastic elongation (%) of the rotor core raw material is shown in Table 4. (Test 5) Test to Evaluate Magnetic Properties

[0357] The rotor core raw material was separated from the rotor core. A small single-sheet magnetic measurement test specimen, with dimensions that allowed the small test specimen to be collected, was prepared by electrical discharge machining from the separated rotor core raw material. The size of the small test specimen was 10 mm by x 20 mm x sheet thickness.

[0358] Magnetic flux density B50 (T) and iron loss The W5 / 1000 (W / kg) of the rotor core raw material was determined using a small test specimen and a single-plate tester according to the single-plate magnetic property test method (single-plate tester: SST) prescribed in JIS C 2556: 2015.

[0359] The magnetic flux density determined B50 (T) and the Petition 870250084752, dated 09 / 19 / 2025, pp. 88 / 111 82 / 86 iron loss W5 / 1000 (W / kg) of the rotor core raw material are shown in Table 4. (Test 6) Test to Evaluate Dimensional Accuracy After Cutting in Blanking

[0360] The rotor core raw material obtained after blanking was cut in 45° increments around the central axis of the rotor core raw material to produce eight test specimens that included the outer peripheral surface side of the rotor core raw material at the time the blanking cut was performed. Each test specimen was embedded in resin and the cut surface was polished to remove 1 mm or more of it, eliminating the influence of deformation that occurred during cutting. After polishing, the cut surface of a portion near the outer peripheral surface of the rotor core raw material was observed using an optical microscope at a magnification of 100 χ.As illustrated in Figure 6, a line segment 20 connecting a point P1 where the cut surface changed from a shear slope face 10 to a blanking end face 11 and a burr tip P2 of the blanking end face 11 was drawn. A line segment 21 that was parallel to line segment 20 and tangent to the blanking end face 11 projecting from line segment 20 was drawn. The distance d between line segment 20 and line segment 21 was determined. The arithmetic mean of the distances d (a total of eight distances d) determined on the eight test specimens was defined as the blanking cut flatness (μm). The determined blanking cut flatness (pm) of the rotor core raw material is shown in Table 4.Note that, with respect to the inner peripheral surface side of the rotor core raw material, in some cases, the end face is cut during blanking when cutting during blanking. Petition 870250084752, dated 09 / 19 / 2025, page 89 / 111 The 83 / 86 result may not be maintained due to the processing performed when inserting a shaft or similar. Therefore, as mentioned above, the dimensional accuracy on the end face cut during blanking of a portion near the outer peripheral surface of the rotor core raw material was evaluated. Petition 870250084752, dated 09 / 19 / 2025, pp. 90 / 111 Table 4 Test number Tensile strength TS (MPa) Work hardening degree WH (MPa) Average grain size D (μm) 80- Six10 Formula (4) Elastic elongation (%) Magnetic properties Blanking flatness (μm) Observations Magnetic flux density B50 (T) Iron loss W5 / 1000 (W / kg) 1 610 1 19 47 T 2.2 1.66 16.5 11 Example of the invention 2 591 0 22 45 T 4.3 1.67 16.5 12 Example of the invention 3 640 6 27 38 T 1.0 1.66 15.4 18 Example of the invention 4 600 2 25 44 T 1.9 1.68 16.1 13 Example of the Invention 5 615 2 25 42 T 1.5 1.67 15.7 12 Example of Invention 6 573 2 28 46 T 1.3 1.68 15.6 12 Example of Invention 7 645 3 27 41 T 1.5 1.65 15.0 15 Example of Invention 8 620 4 32 40 T 1.1 1.60 14.6 18 Example of Invention 9 640 2 25 47 T 2.0 1.64 15.6 13 Example of Invention 10 610 1 21 45 T 2.2 1.67 16.4 11 Example of Invention 11 603 0 20 44 T 2.2 1.68 16.9 11 Example of the invention 12 622 9 36 39 T 0.6 1.65 14.5 18 Example of the invention 13 650 6 36 37 T 1.0 1.65 14.2 19 Example of the invention 14 591 8 41 44 T 0.7 1.66 14.5 18 Example of the invention, Petition 870250084752, dated 09 / 19 / 2025, pp. 91-111 84 / 86 Example of the invention: 15 590 2 20 47 T 2.0 1.67 16.7 13 Example of the invention: 16 610 2 20 45 T 2.1 1.67 16.7 12 Example of the invention: 17 603 1 19 48 T 2.4 1.67 16.9 10 Example of the invention: 18 615 2 22 46 T 2.0 1.65 15.8 12 Example of the invention: 19 613 4 26 42 T 1.7 1.67 15.5 13 Example of the invention: 20 615 2 25 44 T 1.8 1.66 15.6 12 Example of the invention: 21 610 1 19 47 T Example of the invention 22 580 11 42 45 T 0.7 1.65 14.3 16 Example of the invention 23 580 2 20 48 T 1.7 1.67 16.4 12 Example of the invention 24 691 1 21 46 T 1.8 1.67 16.2 11 Example of the invention 25 600 1 26 44 T 1.7 1.67 15.8 14 Example of the invention 26 590 2 26 47 T 1.6 1.67 15.4 15 Example of the invention 27 600 2 24 45 T 1.8 1.67 16.2 11 Example of the invention 28 597 8 39 42 T 0.9 1.65 14.8 16 Example of the invention 29 610 2 20 47 T 1.8 1.67 16.6 12 Example of the invention 30 621 6 33 44 T 1.5 1.64 14.3 16 Example of the invention 85 / 86 Petition 870250084752, dated 09 / 19 / 2025, pp. 92 / 111 86 / 86 Evaluation Results

[0361] As shown in Table 4, with respect to the rotor core, in the rotor core raw materials of Tests No. 1 to 30, Characteristic 1 to Characteristic 5 were satisfied. Therefore, in the rotor core raw materials of these test numbers, the blanking cut flatness was 25 μm or less, and therefore, these rotor core raw materials exhibited excellent dimensional accuracy after blanking. Note that, in the rotor core raw materials, the magnetic flux density B50 was 1.60 T or more and the iron loss W5 / 1000 was 16.9 W / kg or less, and therefore, high strength and excellent magnetic properties were obtained.

[0362] Although a preferred embodiment of the non-oriented electrical steel sheet of the present description has been described above, the non-oriented electrical steel sheet of the present description is not limited to the example above. It is evident that those skilled in the art will be able to conceive of various examples of alterations and modifications within the category of the technical idea described in the appended claims, and it should be understood that these also naturally belong to the technical scope of the non-oriented electrical steel sheet of the present description.

Claims

1. Non-oriented electrical steel sheet, characterized in that it consists of, in % by mass: Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010%, and Petition 870250084752, dated 09 / 19 / 2025, p.94 / 111 2 / 7 Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and which satisfies Formula (1) and Formula (2), wherein: a tensile strength TS is greater than 570 MPa; when the stress at 2.0% strain is expressed as Y2,o (MPa) and a yield strength is expressed as YS (MPa), a work hardening degree WH defined by Formula (3) is less than 15 MPa; and an average grain size D (μm) satisfies Formula (4) and the elongation at yield is 0.5% or more; Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) WH = Y2,0-YS (3) D < 80-Six10 (4) where the content of a corresponding element in mass percentage is replaced by each element symbol in Formula (1), Formula (2) and Formula (4) and, if a corresponding element is not contained, 0 is replaced by the corresponding element symbol.

2. Non-oriented electrical steel sheet, according to claim 1, characterized in that it comprises one or more types of elements selected from a group consisting of, in % by mass: Zr: 0.0001 to 0.0100%, Nb: 0.0001 to 0.0100%, V: 0.0001 to 0.0100%, Mo: 0.001 to 0.100%, Cr: 0.001 to 2.000%, La: 0.0001 to 0.0100%, Ce: 0.0001 to 0.0100%, Petition 870250084752, dated 09 / 19 / 2025, p. 95 / 111 3 / 7 B: 0.0001 to 0.0010%, Zn: 0.0001 to 0.0050%, Ga: 0.0001 to 0.0050%, Ge: 0.0001 to 0.0050%, As: 0.0001 to 0.0100%, Ni: 0.001 to 0.500%, Cu: 0.001 to 0.500%, Sn: 0.001 to 0.200%, Sb: 0.001 to 0.100%, Ca: 0.0001 to 0.0050%, Nd: 0.0001 to 0.0010%, and Mg: 0.0001 to 0.0030%.

3. Rotor core, characterized in that it comprises a plurality of rotor core raw materials stacked together, the rotor core raw material consisting, in % by mass, of: Si: 3.1 to 4.5%, C: 0.0025% or less, N: 0.0025% or less, O: 0.0400% or less, P: 0.100% or less, S: 0.0050% or less, Ti: 0.0100% or less, Mn: 2.0% or less, Al: 1.500% or less, Zr: 0 to 0.0100%, Nb: 0 to 0.0100%, V: 0 to 0.0100%, Mo: 0 to 0.100%, Petition 870250084752, of 19 / 09 / 2025, p.96 / 111 4 / 7 Cr: 0 to 2.000%, La: 0 to 0.0100%, Ce: 0 to 0.0100%, B: 0 to 0.0010%, Zn: 0 to 0.0050%, Ga: 0 to 0.0050%, Ge: 0 to 0.0050%, As: 0 to 0.0100%, Ni: 0 to 0.500%, Cu: 0 to 0.500%, Sn: 0 to 0.200%, Sb: 0 to 0.100%, Ca: 0 to 0.0050%, Nd: 0 to 0.0010%, and Mg: 0 to 0.0030%, with the remainder being Fe and impurities, and satisfying Formula (1) and Formula (2), wherein: a tensile strength TS is greater than 570 MPa; when a stress at 2.0% strain is expressed as Y2.0 (MPa) and a yield strength is expressed as YS (MPa), a work hardening degree WH defined by Formula (3) is less than 15 MPa; and an average grain size D (μm) satisfies Formula (4) and an elongation of elasticity is 0.5% or more; Si / 28+Ti / 48+Nb / 93+V / 51+Zr / 91+Mo / 96+Cr / 52 > C / 12 x750 (1) Si / 28+Al / 27+Ti / 48+Zr / 91+La / 139+Ce / 140 > N / 14 x1000 (2) WH = Y2.0 -YS (3) D < 80-Six10 (4) where a content of a corresponding element in percentage in Petition 870250084752, of 19 / 09 / 2025, p.97 / 111 5 / 7 mass is replaced by each element symbol in Formula (1), Formula (2) and Formula (4) and, if a corresponding element is not contained, 0 is replaced by the symbol of the corresponding element.

4. Rotor core, according to claim 3, characterized in that the raw material of the rotor core comprises one or more types of elements selected from a group consisting of, in % by mass: Zr: 0.0001 to 0.0100%, Nb: 0.0001 to 0.0100%, V: 0.0001 to 0.0100%, Mo: 0.001 to 0.100%, Cr: 0.001 to 2.000%, La: 0.0001 to 0.0100%, Ce: 0.0001 to 0.0100%, B: 0.0001 to 0.0010%, Zn: 0.0001 to 0.0050%, Ga: 0.0001 to 0.0050%, Ge: 0.0001 to 0.0050%, As: 0.0001 to 0.0100%, Ni: 0.001 to 0.500%, Cu: 0.001 to 0.500%, Sn: 0.001 to 0.200%, Sb: 0.001 to 0.100%, Ca: 0.0001 to 0.0050%, Nd: 0.0001 to 0.0010%, and Mg: 0.0001 to 0.0030%.

5. Motor, characterized in that it comprises the rotor core, as defined in claim 3 or 4.

6. Method for producing non-oriented electrical steel sheet, as defined in claim 1 or 2, characterized by the fact Petition 870250084752, dated 09 / 19 / 2025, p. 98 / 111 6 / 7 comprising: a hot rolling process consisting of subjecting a plate to hot rolling to produce a hot-rolled steel sheet, a cold rolling process consisting of subjecting the hot-rolled steel sheet to cold rolling to produce a cold-rolled steel sheet, and a final annealing process consisting of subjecting the cold-rolled steel sheet to final annealing in a final annealing furnace, wherein, in the final annealing process: the cold-rolled steel sheet is annealed at a maximum attainable temperature T1 of 950 °C or less, a stress TE applied to the cold-rolled steel sheet at the maximum attainable temperature T1 is defined for 2.0 to 10.0 MPa,A residence time t0 (seconds) from an annealing temperature T1 to 700°C in a heating zone, an immersion zone, and a cooling zone of the final annealing furnace, and a residence time t1 (seconds) from 700 to 500°C in the cooling zone are defined to satisfy Formula (A) and Formula (B), at one or more selected locations in the heating zone, immersion zone, and cooling zone within a temperature range of 500°C or more in a furnace atmosphere of the final annealing furnace, a ratio of a partial pressure of water vapor PH20 (atm) to a partial pressure of hydrogen PH2 (atm) becomes greater than 0.05 or an oxygen concentration becomes greater than 0.010%, and a temperature gradient CG in a longitudinal direction of the cold-rolled steel sheet in a cooling process is Petition 870250084752, of 09 / 19 / 2025, p. 99 / 111 7 / 7 of 20 °C / m or less t1-t0 > 0 (A) t1 / t0 < 3.0 (B).,

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