Non-oriented electrical steel sheets and motor cores

Abstract

A non-oriented electrical steel sheet having a chemical composition in mass% of C: 0.006% or less, Si: 1.0% or more or less or less, sol.Al: less than 2.5%, Mn: 3.0% or less, P: 0.30% or less, S: 0.010% or less, N: 0.010% or less, O: 0.10% or less, optionally including other elements, and the remainder being Fe and impurities, having an average crystal grain size of 30㎛ or more or 200㎛ or less, and a {111} density of 2.00 or more or 8.00 or less at a position 1 / 4 of the sheet thickness in the thickness direction from the surface of the steel sheet, and a motor core comprising said non-oriented electrical steel sheet.

Description

Technology Field

[0001] The present disclosure relates to non-oriented electrical steel sheets and motor cores. Background Technology

[0002] Driven by the need to reduce greenhouse gases, products with low energy consumption are being developed in the industrial sector. For example, in the automotive industry, there are fuel-efficient vehicles such as hybrid cars that combine a gasoline engine and a motor, and electric cars driven by a motor. The common technology in these fuel-efficient vehicles is the motor, and increasing motor efficiency has become a critical technology.

[0003] Generally, a motor consists of a stator and a rotor. The non-oriented electrical steel sheets used for the cores of these stators and rotors are required to have low iron losses to achieve high efficiency.

[0004] However, practically speaking, it is necessary to consider the compressive stress applied to the stator and rotor during motor operation. This compressive stress generally degrades the iron loss of non-oriented electrical steel. Therefore, it is desirable for the non-oriented electrical steel used in the stator to have good iron loss under compressive stress.

[0005] For example, Patent Document 1 discloses technology regarding a non-oriented electrical steel sheet with excellent magnetic properties. Patent Document 2 discloses technology regarding a non-oriented electrical steel sheet capable of improving motor efficiency. Patent Document 3 discloses technology regarding a non-oriented electrical steel sheet with excellent magnetic properties. Prior art literature

[0006] Japanese Patent No. 5447167 Publication, Japanese Patent No. 5716315 Publication, International Publication No. 2013 / 069754 The problem to be solved

[0007] The present disclosure is made in consideration of the above-mentioned problems and aims to provide a non-oriented electrical steel sheet and a motor core that are suitable, for example, as materials for a stator core and a rotor core of a motor, and have low deterioration of iron loss when compressive stress is applied. means of solving the problem

[0008] The gist of the present disclosure is as follows.

[0009] [1] Mass %,

[0010] C: 0.006% or less,

[0011] Si: 1.0% or more and 5.0% or less,

[0012] sol.Al: Less than 2.5%,

[0013] Mn: 3.0% or less,

[0014] P: 0.30% or less,

[0015] S: 0.010% or less,

[0016] N: 0.010% or less,

[0017] O: 0.10% or less,

[0018] Sn: 0 to 0.20%,

[0019] Sb: 0 to 0.20%,

[0020] Ca: 0 to 0.01%,

[0021] Cr: 0 to 5.0%,

[0022] Ni: 0 to 5.0%,

[0023] Cu: 0 to 5.0%,

[0024] Ce: 0 to 0.10%,

[0025] B: 0 to 0.10%,

[0026] Mg: 0 to 0.10%,

[0027] Ti: 0 to 0.10%,

[0028] V: 0 to 0.10%,

[0029] Zr: 0 to 0.10%,

[0030] Nd: 0 to 0.10%,

[0031] Bi: 0 to 0.10%,

[0032] W: 0 to 0.10%,

[0033] Mo: 0 to 0.10%,

[0034] Nb: 0 to 0.10%,

[0035] Y: 0 to 0.10%,

[0036] Remainder: Fe and impurities

[0037] Having a chemical composition consisting of,

[0038] The average crystal grain size is 30㎛ or more and 200㎛ or less, and

[0039] At a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate, {111} <011> Non-oriented electrical steel sheet with an integration density of 2.00 or more and 8.00 or less.

[0040] [2] Mass %,

[0041] Sn: 0.0010% or more and 0.20% or less,

[0042] Sb: 0.0010% or more and 0.20% or less,

[0043] Ca: 0.0003% or more and 0.01% or less,

[0044] Cr: 0.0010% or more and 5.0% or less,

[0045] Ni: 0.0010% or more and 5.0% or less,

[0046] Cu: 0.0010% or more and 5.0% or less,

[0047] Ce: 0.001% or more and 0.10% or less,

[0048] B: 0.0001% or more and 0.10% or less,

[0049] Mg: 0.0001% or more and 0.10% or less,

[0050] Ti: 0.0001% or more and 0.10% or less,

[0051] V: 0.0001% or more and 0.10% or less,

[0052] Zr: 0.0002% or more and 0.10% or less,

[0053] Nd: 0.002% or more and 0.10% or less,

[0054] Bi: 0.002% or more and 0.10% or less,

[0055] W: 0.002% or more and 0.10% or less,

[0056] Mo: 0.002% or more and 0.10% or less,

[0057] Nb: 0.0001% or more and 0.10% or less, and

[0058] Y: 0.002% or more, 0.10% or less

[0059] A non-oriented electrical steel sheet described in [1] comprising one or more types selected from the group consisting of

[0060] [3] At a position 1 / 4 of the plate thickness in the direction of plate thickness from the surface of the above steel plate, {110} <001> Non-oriented electrical steel sheet as described in [1] or [2] with an integration density of 1.00 or higher.

[0061] [4] At a position 1 / 4 of the plate thickness in the direction of plate thickness from the surface of the above steel plate, {111} <112> Integration density / {111} <011> A non-oriented electrical steel sheet described in any one of [1] to [3] having an integration density value of 1.00 or less.

[0062] [5] At a position 1 / 4 of the plate thickness in the direction of plate thickness from the surface of the above steel plate, {411} <148> A non-oriented electrical steel sheet described in any one of [1] to [4] with an integration density of 2.00 or less.

[0063] [6] At a position 1 / 4 of the plate thickness in the direction of plate thickness from the surface of the above steel plate, {411} <011> A non-oriented electrical steel sheet described in any one of [1] to [5] with an integration density of 2.00 or less.

[0064] [7] A non-oriented electrical steel sheet described in any one of [1] to [6], having a thickness of 0.10 mm or more and 0.35 mm or less at a position 1 / 4 of the thickness of the sheet from the surface of the steel sheet in the direction of the thickness of the sheet.

[0065] [8] A motor core having a structure in which multiple non-oriented electrical steel sheets described in any one of [1] to [7] are laminated. Effects of the invention

[0066] According to the above aspects of the present disclosure, it is possible to provide a non-oriented electrical steel sheet and a motor core that can be suitably used, for example, as a material for a stator core and a rotor core of a motor, and have low deterioration of iron loss when compressive stress is applied. Specific details for implementing the invention

[0067] A suitable embodiment of the non-oriented electrical steel sheet of the present disclosure is described in detail below. However, the present disclosure is not limited to the configuration disclosed in the following embodiment, and various modifications are possible within the scope of the present disclosure without departing from the spirit of the present disclosure. Furthermore, regarding the numerical limit ranges in the present disclosure, unless otherwise specifically stated, the values ​​described as lower and upper limits, respectively, are included within the range. However, values ​​indicated as "greater than" or "less than" are not included within the numerical range. "%" regarding the content of each element means "mass%".

[0068] In addition, regarding the numerical ranges described stepwise in this specification, the upper limit of any stepwise numerical range may be substituted with the upper limit of another stepwise numerical range, or may be substituted with the value shown in the example.

[0069] In the numerical ranges described stepwise in this specification, the lower limit of any stepwise numerical range may be substituted with the lower limit of another stepwise numerical range, or may be substituted with the value shown in the examples.

[0070] In addition, if a desirable lower limit and an upper limit are specified for the content of each element, a numerical range obtained by arbitrarily combining the lower and upper limits may be used as the desirable content of that element.

[0071] In addition, regarding the content of an element, if the lower limit is stated as 0% or as "0 to" or "0% or more," or if only the upper limit is stated, it means that the element does not need to be included.

[0072] [Non-oriented electrical steel]

[0073] The non-oriented electrical steel sheet according to the present disclosure can be suitably used as an iron core for motors such as electric vehicles or hybrid vehicles. Here, the term "non-oriented electrical steel sheet" includes not only coil products but also steel sheets (iron core materials) constituting the iron core.

[0074] That is, in each embodiment of the present disclosure, the term "non-oriented electrical steel sheet" includes not only "steel sheets" in the form of coils or folds manufactured by a steel sheet manufacturer, but also "steel sheets" that are processed into a motor core shape by, for example, punching, lamination, etc., by a customer and constitute a motor core.

[0075] (Chemical composition)

[0076] First, the reason for limiting the chemical composition of the non-oriented electrical steel sheet according to the present disclosure will be explained.

[0077] The non-oriented electrical steel sheet according to the present disclosure contains Si as a chemical composition, contains optionally selected elements, and the remainder consists of Fe and impurities. Each element is described below.

[0078] C: 0% or more, 0.006% or less

[0079] C (carbon) is an element that is contained as an impurity and degrades magnetic properties. Therefore, the C content is 0.006% or less. Preferably, it is 0.003% or less. Since a low C content is desirable, there is no need to limit the lower limit, and the lower limit may be 0%. However, since it is not easy to industrially reduce the content to 0%, the lower limit may be 0.0005% or 0.0010%.

[0080] Si: 1.0% or more and 5.0% or less

[0081] Silicon (Si) is an element effective in reducing iron loss by increasing the resistivity of the steel sheet. Therefore, the Si content is set to 1.0% or more. In addition, Si is an element effective in reducing magnetic anisotropy and mechanical anisotropy within the sheet surface as a non-oriented electrical steel sheet for motor cores. In this case, the Si content is preferably greater than 2.0% and less than or equal to 5.0%, more preferably greater than or equal to 2.5% and less than or equal to 5.0%, more preferably greater than or equal to 3.0% and less than or equal to 5.0%, and more preferably greater than or equal to 3.2% and less than or equal to 5.0%. On the other hand, if the content is excessive, the magnetic flux density decreases significantly. Therefore, the Si content is set to 5.0% or less. From the perspective of suppressing the decrease in magnetic flux density, the Si content is preferably 1.0% or more and 4.5% or less, more preferably 1.0% or more and 4.0% or less, and even more preferably 1.0% or more and 3.5% or less.

[0082] sol.Al: 0% or more and less than 2.5%

[0083] Aluminum (Al) is an effective selective element for increasing the resistivity of steel sheets and reducing iron loss, but if contained in excess, the magnetic flux density decreases significantly. For this reason, the sol.Al content is kept below 2.5%. There is no need to limit the lower value of the sol.Al content, so the lower limit may be 0%. However, to obtain the effect resulting from the above action more reliably, it is preferable to have a sol.Al content of 0.03% or more, and more preferable to have a sol.Al content of 0.10% or more. Furthermore, sol.Al refers to acid-soluble aluminum.

[0084] Here, Si and Al are elements effective in reducing magnetic anisotropy within the plate plane and also reducing mechanical anisotropy within the plate plane. For this reason, the total content of Si and sol.Al is preferably greater than 2.0%, more preferably greater than 3.0%, and more preferably greater than 4.0%. On the other hand, since Si and Al have high solid solution strengthening capabilities, cold rolling becomes difficult if they are included in excess. Therefore, it is preferable that the total content of Si and sol.Al be less than 5.5%.

[0085] Mn: 0% or more, 3.0% or less

[0086] Manganese (Mn) is an effective selective element for reducing iron loss by increasing the resistivity of steel sheets. However, since the alloying cost of Mn is higher than that of Si or Al, increasing the Mn content becomes economically disadvantageous. For this reason, the Mn content is set to 3.0% or less. The Mn content is preferably 2.7% or less, and more preferably 2.5% or less. There is no need to limit the lower limit of the Mn content, so the lower limit may be 0%. However, to obtain the effect of the above action more reliably, the Mn content is preferably 0.0010% or more, more preferably 0.0030% or more, and even more preferably 0.010% or more.

[0087] P: 0% or more, 0.30% or less

[0088] Phosphorus (P) is an element generally contained as an impurity. However, since P improves the texture of non-oriented electrical steel sheets and enhances magnetic properties, it may be included as necessary. However, because P is also a solid solution strengthening element, if the P content becomes excessive, the steel sheet becomes hardened, making cold rolling difficult. For this reason, the P content is set to 0.30% or less. It is preferable that the P content be 0.20% or less. There is no need to limit the lower value of the P content, so the lower limit may be 0%. However, to obtain the effect of the above action more reliably, it is preferable that the P content be 0.0010% or more, more preferable that it be 0.010% or more, and even more preferable that it be 0.015% or more.

[0089] S: 0% or more, 0.010% or less

[0090] Sulfur (S) is contained as an impurity and combines with Mn in the steel to form fine MnS, which inhibits grain growth during annealing and degrades the magnetic properties of non-oriented electrical steel sheets. For this reason, the S content is to be 0.010% or less. It is preferable that the S content be 0.005% or less, and more preferable that it be 0.003% or less. Since it is desirable that the S content be low, there is no need to limit the lower limit, so the lower limit may be 0%. However, since it is not easy to industrially reduce the content to 0%, the lower limit may be 0.0001% or 0.001%.

[0091] N: 0% or more, 0.010% or less

[0092] Nitrogen (N) is contained as an impurity and combines with Al to form fine AlN, which inhibits grain growth during annealing and degrades magnetic properties. For this reason, the N content is kept at 0.010% or less. It is preferable that the N content be 0.005% or less, and more preferable that it be 0.003% or less. Since it is desirable that the N content be low, there is no need to limit the lower limit, so the lower limit may be 0%. However, since it is not easy to industrially reduce the content to 0%, the lower limit may be 0.0001% or more, 0.0010% or more, or 0.0015% or more.

[0093] O: 0% or more, 0.10% or less

[0094] O (oxygen) is contained as an impurity and forms oxides, which degrade magnetic properties. For this reason, the O content is kept at 0.10% or less. It is preferable that the O content be 0.08% or less, more preferable that it be 0.05% or less, even more preferable that it be 0.010% or less, and particularly preferable that it be 0.008% or less. Since it is desirable for the O content to be low, there is no need to limit the lower limit, so the lower limit may be 0%. However, since it is not easy to industrially reduce the content to 0%, the lower limit may be 0.0001% or more, 0.0005% or more, or 0.0008% or more.

[0095] The chemical composition of the non-oriented electrical steel sheet according to the present disclosure may contain, in addition to the above elements, at least one of Sn, Sb, Ca, Cr, Ni, Cu, and Ce as an optional element. For example, the content of these optional elements may be less than or equal to the following.

[0096] Sn: 0% or more, 0.20% or less

[0097] Sb: 0% or more, 0.20% or less

[0098] Sn (tin) and Sb (antimony) are optional elements that improve magnetic properties (e.g., magnetic flux density) by improving the texture of non-oriented electrical steel sheets, so they may be included as needed. However, if Sn and / or Sb are included in excess, the steel may become embrittled, leading to cold-rolled fracture, and the magnetic properties may also deteriorate. For this reason, the content of Sn and Sb is set to 0.20% or less for each. There is no need to limit the lower limit for the content of Sn and Sb, so the lower limit may be 0%. However, to obtain the effect of the above action more reliably, the Sn content is preferably 0.0010% or more, and more preferably 0.01% or more. Additionally, the Sb content is preferably 0.0010% or more, preferably 0.002% or more, and more preferably 0.01% or more.

[0099] Ca: 0% or more, 0.01% or less

[0100] Calcium (Ca) is an effective selective element for controlling inclusions because it suppresses the precipitation of fine sulfides (MnS, Cu2S, etc.) by generating coarse sulfides. When added appropriately, it improves grain growth and enhances magnetic properties (e.g., iron loss). However, if Ca is included in excess, the effects resulting from the above action become saturated, leading to increased costs. Therefore, the Ca content should be 0.01% or less. It is preferable that the Ca content be 0.008% or less, and more preferable that it be 0.005% or less. There is no need to limit the lower value of the Ca content, so the lower limit may be 0%. However, to obtain the effects resulting from the above action more reliably, it is preferable that the Ca content be 0.0003% or more. It is preferable that the Ca content be 0.001% or more, and more preferable that it be 0.002% or more.

[0101] Cr: 0% or more, 5.0% or less

[0102] Chromium (Cr) is a selected element that increases resistivity and improves magnetic properties (e.g., iron loss). However, if included in excess, it may lower the saturation magnetic flux density, and furthermore, the effect resulting from the above action becomes saturated, leading to an increase in costs. Therefore, the Cr content is set to 5.0% or less. The Cr content may be 4.0% or less, preferably 0.5% or less, and more preferably 0.1% or less. There is no need to limit the lower value of the Cr content, so the lower limit may be 0%. However, to obtain the effect resulting from the above action more reliably, the Cr content is preferably 0.0010% or more.

[0103] Ni: 0% or more, 5.0% or less

[0104] Nickel (Ni) is a selective element that improves magnetic properties (e.g., saturation magnetic flux density). However, if Ni is contained in excess, the effect of the above action becomes saturated, leading to an increase in costs. Therefore, the Ni content is set to 5.0% or less. The Ni content may be 4.0% or less, preferably 0.5% or less, and more preferably 0.1% or less. There is no need to limit the lower limit of the Ni content, so the lower limit may be 0%. However, to obtain the effect of the above action more reliably, the Ni content is preferably 0.0010% or more.

[0105] Cu: 0% or more and 5.0% or less,

[0106] Copper (Cu) is a selective element that improves the strength of steel sheets. However, if Cu is included in excess, it may lower the saturation magnetic flux density, and furthermore, the effect resulting from the above action becomes saturated, leading to an increase in costs. Therefore, the Cu content is set to 5.0% or less. The Cu content may be 4.0% or less, and it is preferable that it be 0.1% or less. There is no need to limit the lower value of the Cu content, so the lower limit may be 0%. However, to obtain the effect resulting from the above action more reliably, it is preferable that the Cu content be 0.0010% or more.

[0107] Ce: 0% or more, 0.10% or less

[0108] Cerium (Ce) is a selective element that reduces iron loss by improving grain growth characteristics, thereby suppressing the precipitation of fine sulfides (MnS, Cu2S, etc.) through the formation of coarse sulfides and acid sulfides. However, if contained in excess, oxides are also formed in addition to sulfides and acid sulfides, which may degrade iron loss; furthermore, the effects resulting from the above action become saturated, leading to increased costs. Therefore, the Ce content should be 0.10% or less. It is preferable that the Ce content be 0.01% or less. There is no need to limit the lower value of the Ce content, so the lower limit may be 0%. However, to obtain the effects resulting from the above action more reliably, it is preferable that the Ce content be 0.001% or more. It is even more preferable that the Ce content be 0.002% or more, 0.003% or more, and 0.005% or more.

[0109] The chemical composition of the non-oriented electrical steel sheet according to the present disclosure may also contain at least one of, for example, B, Mg, Ti, V, Zr, Nd, Bi, W, Mo, Nb, and Y as an optional element. The content of these optional elements may be controlled based on known knowledge. For example, the content of these optional elements may be less than or equal to the following.

[0110] B: 0% or more and 0.10% or less,

[0111] Mg: 0% or more and 0.10% or less,

[0112] Ti: 0% or more and 0.10% or less,

[0113] V: 0% or more and 0.10% or less,

[0114] Zr: 0% or more and 0.10% or less,

[0115] Nd: 0% or more, 0.10% or less,

[0116] Bi: 0% or more and 0.10% or less,

[0117] W: 0% or more and 0.10% or less,

[0118] Mo: 0% or more and 0.10% or less,

[0119] Nb: 0% or more and 0.10% or less,

[0120] Y: 0% or more, 0.10% or less.

[0121] In addition, the non-oriented electrical steel sheet according to the present disclosure comprises, in addition to containing 1.0% or more and 5.0% or less of Si, a chemical composition in mass%,

[0122] C: 0.0010% or more and 0.006% or less,

[0123] sol.Al: 0.10% or more and less than 2.5%,

[0124] Mn: 0.0010% or more and 3.0% or less,

[0125] P: 0.0010% or more and 0.30% or less,

[0126] S: 0.0001% or more and 0.010% or less,

[0127] N: Greater than 0.0015% and less than or equal to 0.010%,

[0128] O: 0.0001% or more and 0.10% or less,

[0129] Sn: 0.0010% or more and 0.20% or less,

[0130] Sb: 0.0010% or more and 0.20% or less,

[0131] Ca: 0.0003% or more and 0.01% or less,

[0132] Cr: 0.0010% or more and 5.0% or less,

[0133] Ni: 0.0010% or more and 5.0% or less,

[0134] Cu: 0.0010% or more and 5.0% or less,

[0135] Ce: 0.001% or more and 0.10% or less,

[0136] B: 0.0001% or more and 0.10% or less,

[0137] Mg: 0.0001% or more and 0.10% or less,

[0138] Ti: 0.0001% or more and 0.10% or less,

[0139] V: 0.0001% or more and 0.10% or less,

[0140] Zr: 0.0002% or more and 0.10% or less,

[0141] Nd: 0.002% or more and 0.10% or less,

[0142] Bi: 0.002% or more and 0.10% or less,

[0143] W: 0.002% or more and 0.10% or less,

[0144] Mo: 0.002% or more and 0.10% or less,

[0145] Nb: 0.0001% or more and 0.10% or less, and

[0146] Y: 0.002% or more and 0.10% or less,

[0147] It is desirable to contain at least one of the following.

[0148] It is preferable that the B content be 0.02% or less, and more preferable that it be 0.01% or less.

[0149] It is preferable that the Mg content be 0.01% or less, and more preferable that it be 0.005% or less.

[0150] It is preferable that the Ti content be 0.100% or less, and more preferable that it be 0.002% or less.

[0151] It is preferable that the V content be 0.05% or less, and more preferable that it be 0.04% or less.

[0152] It is preferable that the Zr content be 0.08% or less, and more preferable that it be 0.06% or less.

[0153] It is preferable that the Nd content be 0.05% or less, and more preferable that it be 0.01% or less.

[0154] It is preferable that the Bi content be 0.05% or less, and more preferable that it be 0.01% or less.

[0155] It is preferable that the W content be 0.05% or less, and more preferable that it be 0.01% or less.

[0156] It is preferable that the Mo content be 0.05% or less, and more preferable that it be 0.01% or less.

[0157] It is preferable that the Nb content be 0.05% or less, and more preferable that it be 0.03% or less.

[0158] It is more preferable that the Y content be 0.05% or less, and more preferable that it be 0.01% or less.

[0159] In addition, from the perspective of being able to produce the effects described below, the desirable lower limit of the content of each element is as follows.

[0160] It is desirable that the B content be 0.0002% or more.

[0161] It is desirable that the Mg content be 0.0004% or more.

[0162] It is preferable that the Ti content be 0.001% or more.

[0163] It is desirable that the V content be 0.002% or more.

[0164] It is desirable that the Zr content be 0.002% or more.

[0165] It is desirable that the Nd content be 0.002% or more.

[0166] It is desirable that the Bi content be 0.002% or more.

[0167] It is preferable that the W content be 0.002% or more.

[0168] It is desirable that the Mo content be 0.002% or more.

[0169] It is desirable that the Nb content be 0.002% or more.

[0170] It is desirable that the Y content be 0.002% or more.

[0171] The above arbitrary elements are divided into the following groups A to E based on the difference in the effect caused by each element.

[0172] [Group A] Sn, Sb, Ca, Cr, Ni, Cu, Ce

[0173] An element capable of improving magnetic and / or mechanical properties through texture, inclusion control, resistivity, saturation flux density, solid solution strengthening, etc.

[0174] [Group B] Ti, V, Zr, Nb

[0175] An element capable of improving grain growth through the coarsening of precipitates

[0176] [Group C] Mg, Nd, Bi, Y

[0177] An element capable of controlling inclusions such as sulfides and oxides

[0178] [Group D] B

[0179] Elements capable of producing suitable effects through nitride control

[0180] [E-gun]

[0181] An element capable of producing an effect suitable for improving mechanical properties

[0182] W, Mo

[0183] The non-oriented electrical steel sheet according to the present disclosure may include one or more types selected from the group consisting of groups A to E, and may include, for example, one or more elements among groups A, B, C, D, and / or E.

[0184] The chemical composition described above can be measured by general analytical methods. For example, the chemical composition can be measured using ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry). Additionally, sol.Al can be measured by ICP-AES using the filtrate obtained after heating and decomposing the sample with acid. Furthermore, Si can be measured using ICP emission spectroscopy, C and S using combustion-infrared absorption, N using inert gas melting-thermal conductivity, and O using inert gas melting-non-dispersive infrared absorption.

[0185] Furthermore, the above chemical composition is the composition of a non-oriented electrical steel sheet that does not contain an insulating film, etc. If the non-oriented electrical steel sheet to be measured has an insulating film, etc. on its surface, it is measured after removing it. For example, the insulating film, etc. may be removed by the following method. First, the non-oriented electrical steel sheet having an insulating film, etc. is immersed in an aqueous sodium hydroxide solution, an aqueous sulfuric acid solution, and an aqueous nitric acid solution in that order, and then washed. Finally, it is dried with hot air. By doing so, a non-oriented electrical steel sheet with the insulating film removed can be obtained. Alternatively, the insulating film, etc. may be removed by grinding.

[0186] (Characteristics of the determination orientation)

[0187] The non-oriented electrical steel sheet according to the present disclosure is, at a position 1 / 4 of the sheet thickness in the thickness direction from the surface of the steel sheet, {111} <011> The degree of integration is 2.00 or higher and 8.00 or lower (hereinafter, the description “at a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate” may be omitted).

[0188] In addition, the term "integration" of the crystal orientation in this disclosure is an indicator commonly used when indicating a texture. For example, {111} <011> Integration refers to the crystal orientation {111} <011> It is an indicator showing how many times the frequency of existence of crystal grains having [this] is compared to a structure with a random orientation distribution (in this case, the degree of accumulation is 1).

[0189] The non-oriented electrical steel sheet according to the present disclosure is, at a position 1 / 4 of the sheet thickness in the sheet thickness direction from the surface of the steel sheet, {111} <011> In addition to having an integration density of 2.00 or more and 8.00 or less, preferably {110} <001> Integration density 1.00 or greater, {111} <112> Integration density / {111} <011> The value of the integration density is 1.00 or less, {411} <148> Integration density 2.00 or less, and {411} <011> It satisfies at least one of the following: an integration density of 2.00 or less.

[0190] {111} <011> An integration density of 2.00 or more and 8.00 or less is an important feature of the non-oriented electrical steel sheet of the present disclosure. {111} <011> The orientation is one that has good magnetic properties when stress is applied.

[0191] In addition, the inventors, as shown below, {111} <011> At the same time {110} <001> Direction, {111} <112> Direction, {411} <148> Direction, and {411} <011> By appropriately controlling at least one of the orientation concentrations, it was successful to achieve a high level of compatibility between magnetic properties in normal conditions and under stress application.

[0192] {110} <001> The orientation is an orientation with excellent magnetic properties, and it is desirable to have an integration density of 1.00 or higher.

[0193] {111} <112> Although the orientation is capable of minimizing the degradation of magnetic properties when stress is applied, if the integration density is too high, the magnetic properties in the absence of compressive stress decrease. Therefore, the orientation {111}, which has the same plane index and has almost the same effect on magnetic properties, is used. <011> Considering the balance of integration density of {111} <112> Integration density / {111} <011> It is desirable to keep the value of the integration density (ratio of integration density) 1.00 or less.

[0194] {411} <148> The orientation is one in which magnetic properties are prone to deterioration when compressive stress is applied, and it is desirable to keep the integration density at 2.00 or less.

[0195] {411} <011> The orientation is one in which magnetic properties are prone to deterioration when compressive stress is applied, and it is desirable to keep the integration density at 2.00 or less.

[0196] Crystal orientation can be measured by the following method. A steel plate sample of approximately 30 mm × 30 mm, cut from a steel plate, is subjected to mechanical polishing and chemical polishing to remove the surface layer from the steel plate surface to 1 / 4 t portion. Here, the 1 / 4 t portion refers to the portion corresponding to a depth of t × 1 / 4 from the surface, where the thickness of the steel plate is denoted as t. When removing this surface layer, a measurement test specimen is prepared by reducing the thickness of each portion until the 1 / 4 t portion of the original steel plate becomes the surface. Furthermore, when removing the surface layer from the steel plate surface to the 1 / 4 t portion by mechanical polishing and chemical polishing, it may be difficult to strictly obtain the surface of the 1 / 4 t portion, so a certain amount of removal allowance is permitted. Considering the average crystal grain size (30 μm or more and 200 μm or less) of the non-oriented electrical steel plate according to the present disclosure, the degree of accumulation of crystal orientation in the depth direction relative to the 1 / 4 t portion from the steel plate surface can be considered to be of the same degree. Considering the desired plate thickness (0.10 mm or more and 0.35 mm or less), the crystal orientation can be measured by exposing a surface to a depth of 1 / 4 t ± 1 / 8 t, i.e., a range of 1 / 8 t to 3 / 8 t, from the surface of the steel plate through mechanical polishing and chemical polishing.

[0197] After grinding a sample taken from a steel plate to remove up to 1 / 4 of the surface layer, the crystal orientation can be determined by Electron Back Scattering Diffraction (EBSD). The observation field is 2400 µm per field. 2 More than 2.5mm 2It is preferable to use the average value of each value calculated for multiple fields of view, ranging from two to five locations. From the above observation results, an Orientation Distribution Function (ODF) is created. Based on this Orientation Distribution Function, the degree of integration for each orientation on the surface is obtained. In addition, the expansion order of the ODF is preferably 18 or higher to ensure the accuracy of the degree of integration value.

[0198] (Self-characteristics)

[0199] In the present disclosure, the effect of the invention (suppression of iron loss deterioration when compressive stress is applied) can be verified by using an iron loss W10 / 400 [W / kg] when energized at a magnetic flux density of 1.0T and a frequency of 400Hz. The iron loss is the average value of the characteristics within the plate surface obtained by (WL+WC+2×WD) / 4, where the iron losses when the energization direction is the rolling direction (L direction), the direction perpendicular to rolling (C direction), and the 45° direction (D direction) are denoted as WL, WC, and WD, respectively. In this specification, this characteristic may be referred to as the "overall circumference average (iron loss)." The rolling direction is clear when the non-oriented electrical steel sheet is provided in a coil shape, but it cannot be determined from the shape alone in the case of a folded sheet or when it is removed from a motor core. In this case, the rolling direction can be determined by the grooves on the surface of the steel sheet formed during cold rolling. This method is routinely applied by those skilled in the art, and judging it is not difficult.

[0200] In the present disclosure, the effect of the invention is confirmed by the degree of deterioration Ws-Wn of the total perimeter average iron loss Wn [W / kg] calculated from the iron loss values ​​in each face direction under a no-load condition and the total perimeter average iron loss Ws [W / kg] calculated from the iron loss values ​​in each face direction under a compressive stress of 20 MPa applied in each excitation direction. The non-oriented electrical steel sheet of the present disclosure is preferably configured such that Ws-Wn is 8.50 or less. It is more preferable that Ws-Wn is 8.25 or less, and even more preferable that it is 8.00 or less.

[0201] Each magnetic characteristic may be measured by the Single Sheet Tester (SST) specified in JIS C2556:2015. Additionally, if it is difficult to obtain a test specimen of the size specified in JIS, a test specimen of, for example, 55 mm in width × 55 mm in length may be obtained and measurements may be performed in accordance with the Single Sheet Tester. In that case, it is preferable to use the Epstein equivalent value converted by the Epstein tester specified in JIS C2550:2011.

[0202] (Average crystal size)

[0203] If the crystal grain size is too large or too small, the iron loss under high-frequency conditions may deteriorate. Therefore, the average crystal grain size should be within a general practical range and be 30㎛ or more and 200㎛ or less.

[0204] The average crystal grain size can be measured by the cutting method specified in JIS G0551:2020. For example, in the longitudinal section microstructure image in the plate thickness direction, the average value of the crystal grain size measured by the cutting method with respect to the plate thickness direction and the rolling direction can be used. As this longitudinal section microstructure image, an optical microscope image can be used, for example, a photograph taken at a magnification of 50x can be used.

[0205] (Plate thickness)

[0206] Basically, the thinner the plate thickness, the lower the iron loss. It should be within a general practical range, and preferably 0.35 mm or less. More preferably 0.30 mm or less. On the other hand, since excessive thinning significantly reduces the productivity of the steel plate or motor, it is desirable to make the plate thickness 0.10 mm or more. More preferably 0.15 mm or more.

[0207] The plate thickness may be measured using a micrometer. Additionally, if the non-oriented electrical steel sheet to be measured has an insulating film on its surface, it shall be measured after removing it. The method for removing the insulating film is as described above.

[0208] [Method for manufacturing non-oriented electrical steel sheets]

[0209] Hereinafter, an example of a method for manufacturing a non-oriented electrical steel sheet according to the present disclosure is described. Furthermore, as long as the non-oriented electrical steel sheet according to the present disclosure has the configuration described above, the method of manufacturing is not particularly limited. The following manufacturing method is one example for manufacturing a non-oriented electrical steel sheet according to the present disclosure and is a suitable example of a method for manufacturing a non-oriented electrical steel sheet according to the present disclosure.

[0210] The method for manufacturing a non-oriented electrical steel sheet according to the present disclosure comprises a hot rolling process, a first cold rolling process, an intermediate annealing process, a second cold rolling process, and a final annealing process in this order, and it is effective to apply the following conditions (A) to (E) in particular during these processes. Furthermore, in the following description, the temperature refers to the surface temperature of the steel sheet.

[0211] (A) Heat treatment after hot rolling: During the period from after hot finish rolling until the start of the first cold rolling, heat treatment at 900°C or higher is not performed.

[0212] (B) First cold rolling process: The reduction rate shall be 30% or more and 85% or less.

[0213] (C) Intermediate annealing process: The average heating rate from 500°C to 650°C is set to 300°C / sec or higher and 1000°C / sec or lower, the holding temperature is set to 700°C or higher and 1100°C or lower, the holding time is set to 10 seconds or higher and 300 seconds or lower, and the average cooling rate from 700°C to 500°C is set to 25°C / sec or higher.

[0214] (D) Second cold rolling process: The reduction rate is 30% or more and 75% or less, and the finished plate thickness is 0.10mm or more and 0.35mm or less.

[0215] (E) Finish annealing process: Maintain the holding temperature between 900°C and 1200°C.

[0216] The following describes each process.

[0217] (Hot rolling process)

[0218] The hot-rolled steel sheet provided to the first cold-rolling process above can be obtained by performing hot rolling on a steel ingot or steel billet (hereinafter also referred to as a "slab") having the chemical composition described above.

[0219] In hot rolling, steel having the above chemical composition is formed into a slab by a general method, such as continuous casting or break-rolling of an ingot, and then charged into a furnace to perform hot rolling. At this time, if the temperature of the slab is high, hot rolling may be performed without charging it into a furnace.

[0220] The various conditions for hot rolling are not particularly limited. Generally, conditions such as a slab heating temperature of 950 to 1250°C, a finishing temperature of 700 to 1000°C, and a finished plate thickness of about 1.0 to 4.0 mm are adopted.

[0221] (Heat treatment for hot-rolled plates)

[0222] A first cold rolling is subsequently performed on the hot-rolled plate after the hot rolling process is completed. At this time, the hot-rolled steel plate provided to the first cold rolling process is not subjected to heat treatment at 900°C or higher after finishing rolling in the hot process. This restriction is intended to prevent significant changes to the microstructure formed during the hot working process before the first cold rolling. When the exit temperature of the final pass of the hot rolling process is 900°C or higher, cooling begins from the exit side of the final pass and remains in the temperature range of 900°C or higher until it reaches less than 900°C; however, since it is generally cooled to less than 900°C within a few seconds, this period of residence can be ignored in the present disclosure. Accordingly, the heat treatment in the present disclosure is subject to the thermal history performed by hot-rolled plate coiling or hot-rolled plate annealing. If heat treatment of 900°C or higher is performed after the completion of hot finish rolling, the grain size of the hot-rolled sheet increases, thereby changing the structure after the intermediate annealing process, and {111} after the finish annealing specified above <011> The degree of integration is not satisfied. Therefore, it is not desirable to retain heat after hot-rolled plate coiling, and the hot-rolled coiling temperature, which is maintained for a long time, should preferably be 850°C or lower, and more preferably 800°C or lower.

[0223] (1st cold rolling process)

[0224] In the first cold rolling process, a hot-rolled steel sheet having the above chemical composition is cold-rolled with a reduction rate (cumulative reduction rate) of 30% or more and 85% or less.

[0225] If the reduction rate in the first cold rolling process is less than 30% or more than 85%, the desired magnetic properties may not be obtained. Therefore, the reduction rate in the first cold rolling process is set to be 30% or more and 85% or less.

[0226] Conditions for cold rolling other than those mentioned above, such as the steel sheet temperature and rolling roll diameter during cold rolling, are not specifically limited and are to be appropriately selected based on the chemical composition of the hot-rolled steel sheet, the thickness of the steel sheet to be used, etc.

[0227] (Intermediate annealing process)

[0228] In the intermediate annealing process, the cold-rolled steel sheet obtained by the first cold rolling process is subjected to intermediate annealing with an average heating rate from 500°C to 650°C of 300°C / second or higher and 1000°C / second or lower, a holding temperature of 700°C or higher and 1100°C or lower, a holding time of 10 seconds or higher and 300 seconds or lower, and an average cooling rate from 700°C to 500°C of 25°C / second or higher.

[0229] If the above conditions are not satisfied during the intermediate annealing process, the desired magnetic properties may not be obtained. Conditions for intermediate annealing other than those mentioned above are not particularly limited.

[0230] In addition, the average cooling rate from 700℃ to 500℃ does not need to be limited to an upper limit, but if necessary, the upper limit may be set to 70℃ / sec.

[0231] It is preferable that the holding temperature be 850°C or higher. In addition, it is preferable that the holding time be 180 seconds or lower. In addition, it is preferable that the average cooling rate from 700°C to 500°C be 28°C / second or higher. In particular, after satisfying each of the conditions of the present disclosure, if all of the following are satisfied: Si content: greater than 2.0%, average heating rate from 500°C to 650°C: 300°C / second or higher, holding temperature: 850°C or higher, holding time: 180 seconds or lower, and average cooling rate from 700°C to 500°C: 33°C / second or higher, then a non-oriented electrical steel sheet with good magnetic properties when stress is applied can be obtained.

[0232] (2nd cold rolling process)

[0233] In the second cold rolling process, the intermediate annealed steel sheet obtained by the intermediate annealing process is cold rolled with a reduction rate of 30% or more and 75% or less (cumulative reduction rate) to obtain a plate thickness of 0.10mm or more and 0.35mm or less.

[0234] If the reduction rate in the second cold rolling process is less than 30% or more than 75%, the desired magnetic properties may not be obtained. Therefore, the reduction rate in the second cold rolling process is set to be 30% or more and 75% or less.

[0235] It is preferable that the plate thickness be 0.10 mm or more and 0.35 mm or less. It is more preferable that the plate thickness be 0.15 mm or more and 0.30 mm or less.

[0236] Conditions for cold rolling other than those mentioned above, such as the temperature of the steel sheet and the diameter of the rolling rolls during cold rolling, are not specifically limited and are to be appropriately selected based on the chemical composition of the steel sheet, the thickness of the steel sheet to be targeted, etc.

[0237] (Final annealing process)

[0238] In the finishing annealing process, the cold-rolled steel sheet obtained by the second cold rolling process is subjected to finishing annealing at a temperature range of 900°C or higher and 1200°C or lower. This condition is not special and is adopted in the manufacture of general non-oriented electrical steel sheets.

[0239] If the finishing annealing temperature in the finishing annealing process is less than 900°C, the average crystal grain size may be less than 30 μm due to insufficient grain growth, and sufficient magnetic properties may not be obtained. Therefore, the finishing annealing temperature is set to 900°C or higher. On the other hand, if the finishing annealing temperature exceeds 1200°C, {111} characterized by the non-oriented electrical steel sheet of the present disclosure <011> There are cases where grain growth other than orientation becomes dominant and grain growth proceeds excessively, resulting in an average crystal grain size exceeding 200㎛ and insufficient magnetic properties being obtained. Therefore, the finishing annealing temperature is set to 1200℃ or lower.

[0240] The finishing annealing time, maintained in a temperature range of 900°C or higher and 1200°C or lower, does not need to be specifically specified, but it is desirable to keep it at least 1 second to more reliably obtain good magnetic properties. On the other hand, from the perspective of productivity, it is desirable to keep the finishing annealing time at least 120 seconds.

[0241] Conditions for the finishing annealing other than those mentioned above are not specifically limited.

[0242] In addition, this finishing annealing can be performed by the steel sheet manufacturer following the second cold rolling. Alternatively, after shipping the steel sheet after the second cold rolling is completed, it is also possible to perform, for example, punching, steel sheet lamination, and then heat treatment in a core shape, so-called stress relief annealing, at the demander of the steel sheet.

[0243] (Other processes)

[0244] It is desirable to pickle the hot-rolled steel sheet in order to remove the scale formed on the surface of the steel sheet during the above hot rolling and then provide it for cold rolling.

[0245] After the second cold rolling process or the finishing annealing process described above, a coating process may be performed to form an insulating film on the surface of the steel sheet, consisting of only organic components, only inorganic components, or an organic-inorganic composite, according to general methods. From the perspective of reducing environmental burden, it is acceptable to form an insulating film that does not contain chromium. Furthermore, the coating process may be a process of performing an insulating coating that exhibits adhesion by heating and pressurizing. As a coating material that exhibits adhesion, acrylic resin, phenolic resin, epoxy resin, or melamine resin, etc., may be used.

[0246] [use]

[0247] The use of the non-oriented electrical steel sheet according to the present disclosure is not particularly limited, but it is suitable as a material for the stator core and rotor core of a motor. The non-oriented electrical steel sheet according to the present disclosure can be punched into a predetermined shape to form a motor core having a structure in which multiple sheets are stacked. Such a motor core has low deterioration of iron loss when compressive stress is applied, and can contribute to the high efficiency of the motor.

[0248] Examples

[0249] Examples are described below, but the non-oriented electrical steel sheets according to the present disclosure are not limited to the following examples.

[0250] Slabs (ingots) were prepared in a vacuum melting furnace with the chemical compositions shown in Tables 1-1 and 1-2 for the steel grades. Additionally, regarding the components shown in Tables 1-1 and 1-2, the underlined content indicates that it is outside the scope of the present disclosure, and the remainder is Fe and impurities. A blank space indicates that the component (element) was not intentionally added.

[0251] [Table 1-1]

[0252]

[0253] [Table 1-2]

[0254]

[0255] Slabs (steel grades A to B7) with chemical compositions shown in Tables 1-1 and 1-2 were inserted into a furnace and heated to 1100°C, and then hot-rolled to a plate thickness of 2.0 mm to produce hot-rolled steel sheets. The finishing temperature was based on 850°C and the coiling temperature on 600°C. However, for some steel sheets, conditions such as plate thickness, finishing temperature, and coiling temperature were changed. For example, No. a16 was set to a finishing temperature of 930°C and a coiling temperature of 900°C. In addition, No. k1 and v1 were set to a finishing temperature of 1000°C and a coiling temperature of 800°C, and No. n1 was set to a finishing temperature of 800°C and a coiling temperature of 300°C.

[0256] For these hot-rolled steel sheets, hot-rolled sheet annealing, first cold rolling, intermediate annealing, second cold rolling, and finish annealing were performed sequentially. Each condition is as shown in Tables 2-1, 3-1, 4-1, and 5-1.

[0257] In addition, the present embodiment was carried out without forming an insulating film on the surface of the steel plate.

[0258] [Measurement of Average Crystal Size]

[0259] For each steel plate, after finishing annealing, the crystal grain size was measured using an optical microscope image taken at 50x magnification of the cross-section in the plate thickness direction and rolling direction by the cutting method described above, and the average crystal grain size was calculated.

[0260] [Measurement of Collective Organization]

[0261] Measuring test specimens were prepared by reducing the thickness of steel plate samples of approximately 30 mm × 30 mm cut from each steel plate through mechanical polishing and chemical polishing until the surface was 1 / 4 of the original steel plate. The obtained test specimens were observed at five locations using EBSD at a field of view of 900 µm × 2500 µm. From the observation results, a crystal orientation distribution function (ODF) was constructed, and based on the crystal orientation distribution function, the degree of accumulation of each orientation on the surface was obtained. The degree of accumulation of each orientation was determined by adopting the average value of the values ​​calculated for each field of view.

[0262] [Measurement of Self-Characteristics]

[0263] The magnetic properties of each steel plate were measured by SST. The iron loss W10 / 400 [W / kg] was measured when energized with a magnetic flux density of 1.0T and a frequency of 400Hz, and the iron loss Wn [W / kg] was measured under no-load conditions and the iron loss Ws [W / kg] was measured under conditions where a compressive stress of 20MPa was applied in the energization direction, and Ws-Wn was calculated. It was determined that the iron loss when compressive stress is applied is good when Ws-Wn is 8.50 or less.

[0264] The manufacturing conditions of each steel plate are shown in Tables 2-1, 3-1, 4-1, and 5-1, and the texture, average crystal grain size, and magnetic properties are shown in Tables 2-2, 3-2, 4-2, and 5-2, respectively. Additionally, underlines indicate that they are outside the scope of the present disclosure or outside the scope of the aforementioned preferred manufacturing method.

[0265] [Table 2-1]

[0266]

[0267] [Table 2-2]

[0268]

[0269] [Table 3-1]

[0270]

[0271] [Table 3-2]

[0272]

[0273] [Table 4-1]

[0274]

[0275] [Table 4-2]

[0276]

[0277] [Table 5-1]

[0278]

[0279] [Table 5-2]

[0280]

[0281] Manufactured by the chemical composition and preferred manufacturing method of the present disclosure, having an average crystal grain size of 30 μm or more and 200 μm or less, and {111} <011> The steel plate of the example with an integration density of 2.00 or higher and 8.00 or lower had an iron loss degradation (Ws-Wn) of 8.50 W / kg or less, and the iron loss when compressive stress was applied was good.

[0282] Meanwhile, chemical composition, average crystal grain size, or {111} <011> The steel plate of the comparative example, in which the degree of integration is outside the scope of the present disclosure, has an iron loss degradation (Ws-Wn) exceeding 8.50 W / kg, and the iron loss when applying compressive stress was greater than that of the example.

[0283] In addition, No. a20 and a23 in Table 2-2, and No. ab2 and ac2 in Table 5-2 all developed cracks during the first cold rolling, so the steel sheet properties were not measured.

[0284] The disclosures of Japanese Patent Application No. 2022-057541 filed on March 30, 2022, and Japanese Patent Application No. 2022-132805 filed on August 23, 2022, are incorporated herein by reference in their entirety. All documents, patent applications, and technical specifications described herein are incorporated herein by reference to the same extent as individual documents, patent applications, and technical specifications are described individually.

Claims

Claim 1 In mass%, C: 0.006% or less, Si: 1.0% or more and 5.0% or less, sol.Al: less than 2.5%, Mn: 3.0% or less, P: 0.30% or less, S: 0.010% or less, N: 0.010% or less, O: 0.10% or less, Sn: 0 to 0.20%, Sb: 0 to 0.20%, Ca: 0 to 0.01%, Cr: 0 to 5.0%, Ni: 0 to 5.0%, Cu: 0 to 5.0%, Ce: 0 to 0.10%, B: 0 to 0.10%, Mg: 0 to 0.10%, Ti: 0 to 0.10%, V: 0 to 0.10%, Zr: 0 to 0.10%, Nd: It has a chemical composition consisting of 0 to 0.10%, Bi: 0 to 0.10%, W: 0 to 0.10%, Mo: 0 to 0.10%, Nb: 0 to 0.10%, Y: 0 to 0.10%, and the remainder being Fe and impurities, and has an average crystal grain size of 30㎛ or more and 200㎛ or less, and at a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate, {111} <011> Non-oriented electrical steel sheet with an integration density of 2.00 or more and 8.00 or less. Claim 2 In paragraph 1, in mass%, Sn: 0.0010% or more and 0.20% or less, Sb: 0.0010% or more and 0.20% or less, Ca: 0.0003% or more and 0.01% or less, Cr: 0.0010% or more and 5.0% or less, Ni: 0.0010% or more and 5.0% or less, Cu: 0.0010% or more and 5.0% or less, Ce: 0.001% or more and 0.10% or less, B: 0.0001% or more and 0.10% or less, Mg: 0.0001% or more and 0.10% or less, Ti: 0.0001% or more and 0.10% or less, V: 0.0001% or more and 0.10% or less, Zr: 0.0002% or more and 0.10% or less, Nd: A non-oriented electrical steel sheet comprising one or more types selected from the group consisting of 0.002% or more and 0.10% or less, Bi: 0.002% or more and 0.10% or less, W: 0.002% or more and 0.10% or less, Mo: 0.002% or more and 0.10% or less, Nb: 0.0001% or more and 0.10% or less, and Y: 0.002% or more and 0.10% or less. Claim 3 In claim 1, at a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate, {110} <001> Non-oriented electrical steel sheet with an integration density of 1.00 or higher. Claim 4 In claim 1, at a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate, {111} <112> Integration density / {111} <011> Non-oriented electrical steel sheet with an integration density value of 1.00 or less. Claim 5 In claim 1, at a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate, {411} <148> Non-oriented electrical steel sheet with an integration density of 2.00 or less. Claim 6 In claim 1, at a position 1 / 4 of the plate thickness in the plate thickness direction from the surface of the steel plate, {411} <011> Non-oriented electrical steel sheet with an integration density of 2.00 or less. Claim 7 In claim 1, a non-oriented electrical steel sheet having a thickness of 0.10 mm or more and 0.35 mm or less. Claim 8 A motor core having a structure in which multiple non-oriented electrical steel sheets described in any one of claims 1 to 7 are laminated.

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