Non-oriented electromagnetic steel sheet and method for manufacturing the same

Abstract

The non-oriented electromagnetic steel sheet has a prescribed chemical composition, in the precipitates of one or more of sulfides or oxysulfides or both of them selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, particles having a diameter exceeding 0.5 μm are present in 1 or more in a field of view of 10000 μm 2 When observation is performed on a plane parallel to the surface of the steel sheet by EBSD, in a case where the total area is set as S tot , the area of {100} oriented grains is set as S 100 , the area of oriented grains having a Taylor factor M exceeding 2.8 is set as S tyl , the total area of oriented grains having the Taylor factor M of 2.8 or less is set as S tra , the average KAM value of the {100} oriented grains is set as K 100 , the average KAM value of the oriented grains having the Taylor factor M exceeding 2.8 is set as K tyl , 0.20 ≦ S tyl / S tot ≦ 0.85, 0.05 ≦ S 100 / S tot ≦ 0.80, S 100 / S tra ≧ 0.50, K 100 / K tyl ≦ 0.990 are satisfied.

Description

TECHNICAL FIELD

[0001] The present application relates to a non-oriented electromagnetic steel sheet and a method for manufacturing the same.

[0002] This application claims priority based on Japanese Patent Application No. 2021-045986 filed on March 19, 2021, and the contents thereof are hereby incorporated by reference. BACKGROUND

[0003] A non-oriented electromagnetic steel sheet is used for a core of an electric motor, for example, and for the non-oriented electromagnetic steel sheet, excellent magnetic properties, such as low iron loss and high magnetic flux density, are required in a direction parallel to a sheet surface thereof.

[0004] For this reason, it is advantageous to control the texture of the steel sheet in such a manner that the easy magnetization axis of the crystal (<100>) coincides with the in-plane direction. In relation to such texture control, many techniques for controlling {100} orientation, {110} orientation, {111} orientation, and the like are disclosed, such as the techniques described in Patent Documents 1 to 5.

[0005] As a method for controlling the texture, various methods have been proposed. Among them, there is a technique that utilizes strain-induced grain growth. In the strain-induced grain growth under specific conditions, since it is possible to suppress the aggregation of {111} orientation that does not have the easy magnetization axis in the in-plane direction, it is effectively utilized in the non-oriented electromagnetic steel sheet. In relation to these techniques, they are disclosed in Patent Documents 6 to 10 and the like.

[0006] However, in the existing method, although it is possible to suppress the aggregation of {111} orientation, {110} <001> orientation (hereinafter referred to as Goss orientation) grows. The Goss orientation is excellent in magnetic properties in one direction compared to {111}, but there is almost no improvement in the average over the entire circumference. Therefore, in the existing method, there is a problem that excellent magnetic properties cannot be obtained in the average over the entire circumference.

[0007] PRIOR ART DOCUMENTS

[0008] PATENT DOCUMENTS

[0009] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-193754

[0010] Patent Document 2: Japanese Patent Application Laid-Open No. 2011-111658

[0011] Patent Document 3: International Publication No. 2016 / 148010

[0012] Patent Document 4: Japanese Patent Application Laid-Open No. 2018-3049

[0013] Patent Document 5: International Publication No. 2015 / 199211

[0014] Patent Literature 6: Japanese Patent Application Laid-Open No. 8-143960

[0015] Patent Literature 7: Japanese Patent Application Laid-Open No. 2002-363713

[0016] Patent Literature 8: Japanese Patent Application Laid-Open No. 2011-162821

[0017] Patent Literature 9: Japanese Patent Application Laid-Open No. 2013-112853

[0018] Patent Literature 10: Japanese Patent No. 4029430 SUMMARY

[0019] PROBLEMS TO BE SOLVED BY THE INVENTION

[0020] The present application was made in view of the above-described problems, and an object thereof is to provide an unoriented electromagnetic steel sheet and a manufacturing method thereof, which can achieve excellent magnetic properties in the entire circumference average.

[0021] MEANS OF SOLVING THE PROBLEMS

[0022] The present inventors and others have studied techniques for forming a texture preferred for an unoriented electromagnetic steel sheet by strain-induced grain growth. Among others, grains of the {100} <100> orientation (hereinafter referred to as Cube orientation) are also grains that are not easily strained like grains of the Goss orientation. That is, at a stage before strain-induced grain growth occurs, by making the grains of the Cube orientation more than the grains of the Goss orientation, by strain-induced grain growth, mainly grains of the Cube orientation are eroded from grains of the {111} orientation, and an unoriented electromagnetic steel sheet in which the Cube orientation is the main orientation is manufactured. As such, it is known that if the Cube orientation is made the main orientation, the magnetic properties in the entire circumference average (average of the rolling direction, the width direction, the direction 45 degrees with respect to the rolling direction, and the direction 135 degrees with respect to the rolling direction) are improved.

[0023] As a result of further research by the present inventors et al., it was found that, in order to have more cubic-oriented grains than Gaussian-oriented grains at a stage before strain-induced grain growth occurs, it is important to have coarse precipitates with a diameter of more than 0.5 μm in one or more oxides selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd. By the presence of these coarse precipitates, cubic orientation is further strengthened at the time of strain-induced grain growth. It is believed that this is because, at the time of skin pass rolling, which is a main cause of strain-induced grain growth, an uneven deformation region is generated around the coarse precipitates, and strain is easily generated. Furthermore, it is believed that the coarse precipitates sometimes become oxysulfides (oxides containing sulfur) and also have an effect of suppressing the generation of MnS, which hinders growth.

[0024] Based on such insights, the present inventors et al. further repeated intensive research, and as a result, conceived of each aspect of the invention shown below. [1]

[0026] The non-oriented electromagnetic steel sheet of one aspect of the present invention,

[0027] has the following chemical composition: contains, in mass%,

[0028] C: 0.0100% or less,

[0029] Si: 1.50% to 4.00%,

[0030] one or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, and Au: total of less than 2.50%,

[0031] sol. Al: 0.0001% to 3.0000%,

[0032] S: 0.0003% to 0.0100%,

[0033] N: 0.0100% or less,

[0034] one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: total of 0.0003% to 0.0100%,

[0035] Cr: 0.001% to 0.100%,

[0036] Sn: 0.00% to 0.40%,

[0037] Sb: 0.00% to 0.40%,

[0038] P: 0.00% to 0.40%,

[0039] B: 0.0000 to 0.0050%, and

[0040] O: 0.0000 to 0.0200%,

[0041] When the content of Mn is denoted as [Mn] in mass%, the content of Ni is denoted as [Ni] in mass%, the content of Co is denoted as [Co] in mass%, the content of Pt is denoted as [Pt] in mass%, the content of Pb is denoted as [Pb] in mass%, the content of Cu is denoted as [Cu] in mass%, the content of Au is denoted as [Au] in mass%, the content of Si is denoted as [Si] in mass%, and the content of sol. Al is denoted as [sol. Al] in mass%, the following formula (1) is satisfied,

[0042] ([Mn] + [Ni] + [Co] + [Pt] + [Pb] + [Cu] + [Au]) - ([Si] + [sol. Al]) ≦ 0.00%... (1),

[0043] the remainder consists of Fe and impurities;

[0044] Among the precipitates of one or more sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, there are one or more particles having a diameter exceeding 0.5 μm in a field of view of 10000 μm 2 .

[0045] Further, when observation is performed on a plane parallel to the surface of the steel sheet by EBSD, the following formulae (3) to (6) are satisfied in a case where the total area is denoted as S tot , the area of {100} oriented grains is denoted as S 100 , the area of oriented grains having a Taylor factor M exceeding 2.8 according to the following formula (2) is denoted as S tyl , the total area of oriented grains having the Taylor factor M of 2.8 or less is denoted as S tra , the average KAM value of the {100} oriented grains is denoted as K 100 , the average KAM value of the oriented grains having the Taylor factor M exceeding 2.8 is denoted as K tyl .

[0046]

[0047] 0.20 ≦ S tyl / S tot ≦ 0.85... (3),

[0048] 0.05 ≦ S 100 / S tot ≦ 0.80... (4),

[0049] S 100 / S tra ≧0.50…(5),

[0050] K 100 / K tyl ≦0.990…(6),

[0051] In this case, the formula (2) in the formula (2) represents an angle formed by a stress vector and a sliding direction vector of a crystal, and λ represents an angle formed by the stress vector and a normal vector of a sliding surface of the crystal. [2]

[0053] The non-oriented electromagnetic steel sheet according to any one of the above [1] to [3], further, in a case where the average KAM value of the {110} oriented grains is set to K tra , the following formula (7) can be satisfied,

[0054] K 100 / K tra <1.010…(7). [3]

[0056] The non-oriented electromagnetic steel sheet according to any one of the above [1] to [3], further, in a case where the area of the {110} oriented grains is set to S 110 , the following formula (8) can be satisfied,

[0057] S 100 / S 110 ≧1.00…(8),

[0058] In this case, even if the area ratio S 100 / S 110 diverges infinitely, the formula (8) is established. [4]

[0060] The non-oriented electromagnetic steel sheet according to any one of the above [1] to [3], further, in a case where the average KAM value of the {110} oriented grains is set to K 110 , the following formula (9) can be satisfied,

[0061] K 100 / K 110 <1.010…(9). [5]

[0063] The non-oriented electromagnetic steel sheet according to the above [4], further, in a case where the average KAM value of the {110} oriented grains is set to K 2 , the following formula (10) can be satisfied,

[0064] which has the following chemical composition: contains, in mass%,

[0065] C: 0.0100% or less,

[0066] Si: 1.50% to 4.00%,

[0067] one or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, Au: total less than 2.50%,

[0068] sol. Al: 0.0001% to 3.0000%,

[0069] S: 0.0003% to 0.0100%,

[0070] N: 0.0100% or less,

[0071] one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd: total 0.0003% to 0.0100%,

[0072] Cr: 0.001% to 0.100%,

[0073] Sn: 0.00% to 0.40%,

[0074] Sb: 0.00% to 0.40%,

[0075] P: 0.00% to 0.40%,

[0076] B: 0.0000% to 0.0050%, and

[0077] O: 0.0000% to 0.0200%,

[0078] when the Mn content is denoted as [Mn] in mass%, the Ni content is denoted as [Ni] in mass%, the Co content is denoted as [Co] in mass%, the Pt content is denoted as [Pt] in mass%, the Pb content is denoted as [Pb] in mass%, the Cu content is denoted as [Cu] in mass%, the Au content is denoted as [Au] in mass%, the Si content is denoted as [Si] in mass%, and the sol. Al content is denoted as [sol. Al] in mass%, the following formula (1) is satisfied,

[0079] ([Mn] + [Ni] + [Co] + [Pt] + [Pb] + [Cu] + [Au]) - ([Si] + [sol. Al]) ≦ 0.00% (1),

[0080] the remainder consists of Fe and impurities;

[0081] In precipitates of one or more sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, particles having a diameter exceeding 0.5 μm are present in 1 or more in a field of view of 10000 μm 2 ;

[0082] Further, when observation is performed on a plane parallel to the surface of the steel sheet by EBSD, in a case where the total area is set as S tot , the area of the {100} oriented grains is set as S 100 , the area of the oriented grains having a Taylor factor M exceeding 2.8 according to the following formula (2) is set as S tyl , the total area of the oriented grains having a Taylor factor M of 2.8 or less is set as S tra , the average KAM value of the {100} oriented grains is set as K 100 , the average KAM value of the oriented grains having a Taylor factor M exceeding 2.8 is set as K tyl , the average crystal grain size of the observation region is set as d ave , the average crystal grain size of the {100} oriented grains is set as d 100 , the average crystal grain size of the oriented grains having a Taylor factor M exceeding 2.8 is set as d tyl , the following formulas (10) to (15) are satisfied,

[0083]

[0084] S tyl / S tot ≦0.70…(10),

[0085] 0.20≦S 100 / S tot …(11),

[0086] S 100 / S tra ≧0.55…(12),

[0087] K 100 / K tyl ≦1.010…(13),

[0088] d 100 / d ave >1.00…(14),

[0089] d 100 / d tyl >1.00…(15),

[0090] Here, M in formula (2) is represents an angle formed by the stress vector and a sliding direction vector of the crystal, and λ represents an angle formed by the stress vector and a normal vector of a sliding surface of the crystal. [6]

[0092] The non-oriented electromagnetic steel sheet according to any one of [5] to [7], further, in a case where an average KAM value of the oriented grains with the Taylor factor M of 2.8 or less is set to K tra , the following formula (16) can be satisfied,

[0093] K 100 / K tra <1.010…(16)。 [7]

[0095] The non-oriented electromagnetic steel sheet according to any one of [5] to [7], further, in a case where an average crystal grain diameter of the oriented grains with the Taylor factor M of 2.8 or less is set to d tra , the following formula (17) can be satisfied,

[0096] d 100 / d tra >1.00…(17)。 [8]

[0098] The non-oriented electromagnetic steel sheet according to any one of [5] to [7], further, in a case where an area of the {110} oriented grains is set to S 110 , the following formula (18) can be satisfied,

[0099] S 100 / S 110 ≧1.00…(18),

[0100] Here, even if the area ratio S 100 / S 110 diverges infinitely, the formula (18) is established. [9]

[0102] The non-oriented electromagnetic steel sheet according to any one of [5] to [7], further, in a case where an average KAM value of the {110} oriented grains is set to K 110 , the following formula (19) can be satisfied,

[0103] K 100 / K 110 <1.010…(19)。

[10]

[0105] The non-oriented electromagnetic steel sheet according to any one of [1] to [9],

[0106] The chemical composition, in mass%, can also contain one or more selected from the group consisting of

[0107] Sn: 0.02% to 0.40%,

[0108] Sb: 0.02% to 0.40%, and

[0109] P: 0.02% to 0.40%.

[11]

[0111] The manufacturing method of the non-oriented electromagnetic steel sheet according to one aspect of the present application,

[0112] is the manufacturing method of the non-oriented electromagnetic steel sheet according to any one of [5] to [9] above,

[0113] The non-oriented electromagnetic steel sheet according to any one of [1] to [4] above is heat-treated at a temperature of 700 to 950°C for 1 to 100 seconds.

[12]

[0115] The non-oriented electromagnetic steel sheet according to another aspect of the present application,

[0116] has a chemical composition containing, in mass%,

[0117] C: 0.0100% or less,

[0118] Si: 1.50% to 4.00%,

[0119] one or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, Au: total less than 2.50%,

[0120] sol. Al: 0.0001% to 3.0000%,

[0121] S: 0.0003% to 0.0100%,

[0122] N: 0.0100% or less,

[0123] one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd: total 0.0003% to 0.0100%,

[0124] Cr: 0.001% to 0.100%,

[0125] Sn: 0.00% to 0.40%,

[0126] Sb: 0.00% to 0.40%,

[0127] P: 0.00 to 0.40%,

[0128] B: 0.0000 to 0.0050%, and

[0129] O: 0.0000 to 0.0200%,

[0130] When the content of Mn is denoted as [Mn] in mass%, the content of Ni is denoted as [Ni] in mass%, the content of Co is denoted as [Co] in mass%, the content of Pt is denoted as [Pt] in mass%, the content of Pb is denoted as [Pb] in mass%, the content of Cu is denoted as [Cu] in mass%, the content of Au is denoted as [Au] in mass%, the content of Si is denoted as [Si] in mass%, and the content of sol. Al is denoted as [sol. Al] in mass%, the following formula (1) is satisfied,

[0131] ([Mn] + [Ni] + [Co] + [Pt] + [Pb] + [Cu] + [Au]) - ([Si] + [sol. Al]) < 0.00%... (1),

[0132] the remainder consists of Fe and impurities;

[0133] Among the precipitates of one or more sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, there are one or more particles having a diameter exceeding 0.5 μm in a field of view of 10000 μm 2

[0134] Further, when observation is performed on a plane parallel to the surface of the steel sheet by EBSD, the following formulae (20) to (24) are satisfied in a case where the total area is denoted as S tot , the area of the {100} oriented grains is denoted as S 100 , the area of the oriented grains having a Taylor factor M exceeding 2.8 according to the following formula (2) is denoted as S tyl , the total area of the oriented grains having a Taylor factor M of 2.8 or less is denoted as S tra , the average crystal grain size of the observation region is denoted as d ave , the average crystal grain size of the {100} oriented grains is denoted as d 100 , the average crystal grain size of the oriented grains having a Taylor factor M exceeding 2.8 is denoted as d tyl

[0135]

[0136] S tyl / S tot <0.55... (20), ​​

[0137] S 100 / S tot >0.30…(21),

[0138] S 100 / S tra ≧0.60…(22),

[0139] d 100 / d ave ≧0.95…(23),

[0140] d 100 / d tyl ≧0.95…(24),

[0141] In this case, the formula (2) in represents an angle formed by a stress vector and a sliding direction vector of a crystal, and λ represents an angle formed by the stress vector and a normal vector of a sliding surface of the crystal.

[13]

[0143] The non-oriented electromagnetic steel sheet according to the above-mentioned

[12] , further, in a case where the average crystal grain diameter of the oriented crystal grains having the Taylor factor M of 2.8 or less is set as d tra , the following formula (25) can be satisfied,

[0144] d 100 / d tra ≧0.95…(25).

[14]

[0146] The manufacturing method of the non-oriented electromagnetic steel sheet according to the other aspect of the present application,

[0147] The non-oriented electromagnetic steel sheet according to any one of the above-mentioned [1] to

[10] is heat-treated at a temperature of 950 to 1050°C for 1 second to 100 seconds, or at a temperature of 700 to 900°C for more than 1000 seconds.

[0148] Effects of the Invention

[0149] According to the above-mentioned aspect of the present application, it is possible to provide a non-oriented electromagnetic steel sheet capable of obtaining excellent magnetic properties in a whole cycle average and a manufacturing method thereof. DETAILED DESCRIPTION

[0150] Hereinafter, the non-oriented electromagnetic steel sheet according to the embodiment of the present application will be described.

[0151] The non-oriented electromagnetic steel sheet according to the embodiment of the present application is manufactured by manufacturing a cast slab having a predetermined thickness from molten steel having the chemical composition described later, and then, by passing through a hot rolling process, a hot rolled sheet annealing process, a cold rolling process, an intermediate annealing process, and a skin pass rolling process.

[0152] The non-oriented electromagnetic steel sheet of the other embodiment of the present application is manufactured after the hot rolling step, the hot rolled sheet annealing step, the cold rolling step, the intermediate annealing step, the skin pass rolling step, and as needed, the first heat treatment step, and then the second heat treatment step.

[0153] The non-oriented electromagnetic steel sheet of the other embodiment of the present application is manufactured after the hot rolling step, the hot rolled sheet annealing step, the cold rolling step, the intermediate annealing step, the skin pass rolling step, and as needed, the first heat treatment step, and then the second heat treatment step.

[0154] Through the heat treatment after the skin pass rolling, the steel sheet undergoes strain-induced grain growth, and then normal grain growth. The normal grain growth can occur in the first heat treatment step or in the second heat treatment step. The steel sheet after the skin pass rolling is in the relationship of the original sheet of the steel sheet after the strain-induced grain growth and the original sheet of the steel sheet after the normal grain growth. In addition, the steel sheet after the strain-induced grain growth is in the relationship of the original sheet of the steel sheet after the normal grain growth.

[0155] Hereinafter, regardless of before or after the heat treatment, the steel sheet after the skin pass rolling, the steel sheet after the strain-induced grain growth, and the steel sheet after the normal grain growth are all described as the non-oriented electromagnetic steel sheet. In addition, in the metal structure of the steel sheet before the skin pass rolling in the present embodiment, by making the grains centered on the cubic orientation (hereinafter referred to as {100} oriented grains) more than the grains centered on the Goss orientation (hereinafter referred to as {110} oriented grains), the {100} oriented grains are further increased in the subsequent heat treatment step, and the magnetic property of the whole circumference is improved.

[0156] First, the chemical composition of molten steel used in the non-oriented electromagnetic steel sheet and the manufacturing method thereof according to the present embodiment will be described. Since the chemical composition does not change in the processes of rolling, heat treatment, and the like, the chemical composition described below is also the chemical composition of the molten steel and the chemical composition of the non-oriented electromagnetic steel sheet. In addition, in the following description, "%" as a unit of the content of each element contained in the non-oriented electromagnetic steel sheet or the molten steel means "mass %" unless otherwise specified. The non-oriented electromagnetic steel sheet and the molten steel according to the present embodiment have the following chemical composition: C: 0.0100% or less, Si: 1.50% to 4.00%, one or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, Au: total less than 2.50%, sol. Al: 0.0001% to 3.0000%, S: 0.0003% to 0.0100%, N: 0.0100% or less, one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: total 0.0003% to 0.0100%, Cr: 0.001% to 0.100%, Sn: 0.00% to 0.40%, Sb: 0.00% to 0.40%, P: 0.00% to 0.40%, B: 0.0000% to 0.0050%, and O: 0.0000% to 0.0200%, and the remainder consisting of Fe and impurities. As the impurities, impurities contained in raw materials such as ores, scrap, and the like, and impurities contained in the manufacturing processes can be exemplified.

[0157] (C: 0.0100% or less)

[0158] C increases the electrical resistance, reduces the eddy current loss to lower the iron loss, or increases the yield ratio to improve the blanking workability for the core. When the C content is less than 1.50%, these effects cannot be sufficiently obtained. Therefore, the C content is set to 1.50% or more. The C content is preferably 2.0% or more, more preferably 2.10% or more, and further preferably 2.30% or more. On the other hand, when the C content exceeds 4.00%, the magnetic flux density decreases, or the blanking workability decreases due to excessive increase in hardness, or cold rolling becomes difficult. Therefore, the C content is set to 4.00% or less.

[0159] (Si: 1.50% to 4.00%)

[0160] Si increases the electrical resistance, reduces the eddy current loss to lower the iron loss, or increases the yield ratio to improve the blanking workability for the core. When the Si content is less than 1.50%, these effects cannot be sufficiently obtained. Therefore, the Si content is set to 1.50% or more. The Si content is preferably 2.0% or more, more preferably 2.10% or more, and further preferably 2.30% or more. On the other hand, when the Si content exceeds 4.00%, the magnetic flux density decreases, or the blanking workability decreases due to excessive increase in hardness, or cold rolling becomes difficult. Therefore, the Si content is set to 4.00% or less.

[0161] (One or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, Au: total less than 2.50%)

[0162] These elements are austenite phase (gamma phase) stabilizing elements, and if contained in large amounts, ferrite-austenite phase transformation (hereinafter referred to as a-γ phase transformation) occurs in the heat treatment of the steel sheet. Although it is considered that the effect of the non-oriented electromagnetic steel sheet of the present embodiment is exerted by controlling the area and area ratio of the specific crystal orientation in the cross section parallel to the surface of the steel sheet (steel sheet surface), if a-γ phase transformation occurs in the heat treatment, the above area and area ratio greatly change due to the phase transformation, and a prescribed metal structure cannot be obtained. Therefore, the total of the content of one or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, Au is limited to less than 2.50%. The total of the content is preferably less than 2.00%, and more preferably less than 1.50%. The lower limit of the total of the content of these elements is not particularly limited (may also be 0.00%), but with respect to Mn, from the reason of suppressing fine precipitation of MnS which deteriorates the magnetic properties, it is preferably set to 0.10% or more, and more preferably set to 0.20% or more.

[0163] In addition, as a condition in which a-γ phase transformation does not occur, the following condition is further satisfied. That is, when the Mn content is denoted as [Mn] in mass%, the Ni content is denoted as [Ni] in mass%, the Co content is denoted as [Co] in mass%, the Pt content is denoted as [Pt] in mass%, the Pb content is denoted as [Pb] in mass%, the Cu content is denoted as [Cu] in mass%, the Au content is denoted as [Au] in mass%, the Si content is denoted as [Si] in mass%, and the sol. Al content is denoted as [sol. Al] in mass%, the following formula (1) is satisfied,

[0164] ([Mn] + [Ni] + [Co] + [Pt] + [Pb] + [Cu] + [Au]) - ([Si] + [sol. Al]) ≦ 0.00%... (1).

[0165] (sol. Al: 0.0001% to 3.0000%)

[0166] sol. Al increases the electrical resistance, reduces the eddy current loss, and lowers the iron loss. sol. Al also contributes to increasing the relative size of the magnetic flux density B50 with respect to the saturation magnetic flux density. Here, the magnetic flux density B50 refers to the magnetic flux density in a magnetic field of 5000 A / m. When the sol. Al content is less than 0.0001%, these effects cannot be sufficiently obtained. In addition, Al also has a desulfurization promotion effect in steelmaking. Therefore, the sol. Al content is set to 0.0001% or more. The sol. Al content is preferably set to 0.3000% or more.

[0167] On the other hand, when the sol. Al content exceeds 3.0000%, the magnetic flux density decreases, or the yield ratio decreases, and the blanking workability decreases. Therefore, the sol. Al content is set to 3.0000% or less. The sol. Al content is preferably 2.5000% or less, and further preferably 1.5000% or less.

[0168] (S: 0.0003% to 0.0100%)

[0169] S is an element that forms a sulfide or an oxysulfide selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd. In order to obtain a prescribed sulfide or oxysulfide, the S content is set to 0.0003% or more. The S content is preferably 0.0010% or more.

[0170] On the other hand, S hinders recrystallization and grain growth during annealing by precipitating fine MnS. The increase in iron loss and the decrease in magnetic flux density resulting from such hindrance of recrystallization and grain growth are significant when the S content exceeds 0.0100%. Therefore, the S content is set to 0.0100% or less. The S content is preferably 0.0050% or less, and more preferably 0.0020% or less.

[0171] (N: 0.0100% or less)

[0172] N deteriorates magnetic properties as with C, and therefore the N content is preferably as low as possible. Therefore, the N content is set to 0.0100% or less. The lower limit of the N content is not particularly limited, but based on the cost of denitrogenation treatment at the time of refining, it is preferably set to 0.0010% or more.

[0173] (Cr: 0.001% to 0.100%)

[0174] Cr combines with oxygen in the steel to form Cr2O3. This Cr2O3 contributes to improving the texture. In order to obtain the above effect, the Cr content is set to 0.001% or more.

[0175] On the other hand, if the Cr content exceeds 0.100%, the Cr2O3 hinders grain growth at the time of annealing, the crystal grain size becomes fine, and this becomes a main cause of an increase in iron loss. Therefore, the Cr content is set to 0.100% or less.

[0176] (one or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: total 0.0003% to 0.0100%)

[0177] Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn and Cd react with S in molten steel to generate precipitates of sulfides or oxysulfides or both at the time of casting of the molten steel. Hereinafter, Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn and Cd are sometimes collectively referred to as "coarse precipitate generating elements". The precipitates of the coarse precipitate generating elements have a particle size exceeding 0.5 μm (e.g., about 1 to 2 μm), which is much larger than the particle size (about 100 nm) of fine precipitates such as MnS, TiN, AlN and the like. Therefore, these fine precipitates adhere to the precipitates of the coarse precipitate generating elements, and it is difficult for them to hinder the growth of grains in strain-induced grain growth. In addition, by the presence of the coarse precipitates, cubic orientation is further strengthened at the time of strain-induced grain growth. In order to sufficiently obtain these effects, the total of the contents of these coarse precipitate generating elements is set to 0.0003% or more. The total of the contents is preferably 0.0015% or more, more preferably 0.0030% or more. However, if the total of the contents of these elements exceeds 0.0100%, the total amount of sulfides or oxysulfides or both is excessive, and the growth of grains in strain-induced grain growth is hindered. Therefore, the content of the coarse precipitate generating elements is set to 0.0100% or less in total. The total of the contents is preferably 0.0080% or less, more preferably 0.0060% or less.

[0178] (Sn: 0.00% to 0.40%, Sb: 0.00% to 0.40%, P: 0.00% to 0.40%)

[0179] Sn and Sb, if contained in excess, make the steel brittle. Therefore, the Sn content and the Sb content are each set to 0.40% or less. In addition, P, if contained in excess, leads to brittleness of the steel. Therefore, the P content is set to 0.40% or less.

[0180] On the other hand, Sn and Sb have an effect of improving texture after cold rolling and recrystallization, and increasing the magnetic flux density thereof. In addition, P is an effective element for securing the hardness of the steel sheet after recrystallization. Therefore, these elements can be contained as needed. In this case, it is preferable to contain one or more selected from the group consisting of Sn of 0.02% to 0.40%, Sb of 0.02% to 0.40% and P of 0.02% to 0.40%.

[0181] (B: 0.0000% to 0.0050%)

[0182] B, when contained in a small amount, contributes to improvement of texture. Therefore, B can also be contained. In the case where the above effects are obtained, it is preferable to set the B content to 0.0001% or more.

[0183] On the other hand, if the B content exceeds 0.0050%, a compound of B hinders the grain growth at the time of annealing, the crystal grain size becomes fine, and this becomes a main cause of an increase in iron loss. Therefore, the B content is set to 0.0050% or less.

[0184] (O: 0.0000% to 0.0200%)

[0185] O combines with Cr in the steel to form Cr2O3. This Cr2O3 contributes to the improvement of texture. Therefore, O can also be contained. In the case where the above effects are obtained, the O content is preferably set to 0.0010% or more.

[0186] On the other hand, if the O content exceeds 0.0200%, Cr2O3 hinders the grain growth at the time of annealing, the crystal grain size becomes fine, and this becomes a main cause of an increase in iron loss. Therefore, the O content is set to 0.0200% or less.

[0187] Next, the sheet thickness of the non-oriented electromagnetic steel sheet of the present embodiment will be described. The thickness (sheet thickness) of the non-oriented electromagnetic steel sheet of the present embodiment is preferably 0.10 mm to 0.50 mm. If the thickness exceeds 0.50 mm, sometimes excellent high-frequency iron loss cannot be obtained. Therefore, the thickness is preferably 0.50 mm or less. If the thickness is less than 0.10 mm, sometimes the influence of magnetic flux leakage from the surface of the non-oriented electromagnetic steel sheet becomes large, and the magnetic properties deteriorate. In addition, if the thickness is less than 0.10 mm, the passage of the sheet through the annealing line becomes difficult, or the number of non-oriented electromagnetic steel sheets required for a core of a certain size increases, and it can cause a decrease in productivity accompanied by an increase in man-hours and an increase in manufacturing cost. Therefore, the thickness is preferably 0.10 mm or more. More preferably, the thickness is 0.20 mm to 0.35 mm.

[0188] Next, the metal structure of the non-oriented electromagnetic steel sheet of the present embodiment will be described. Hereinafter, the metal structure of the non-oriented electromagnetic steel sheet after skin pass rolling, the metal structure of the non-oriented electromagnetic steel sheet after the first heat treatment, and the metal structure of the non-oriented electromagnetic steel sheet after the second heat treatment are respectively determined for the non-oriented electromagnetic steel sheet of each embodiment.

[0189] First, the metal structure to be determined and a method for determining the same will be described. The metal structure to be determined in the present embodiment is determined in a cross section parallel to the sheet surface, and is determined by the following steps.

[0190] First, polishing is performed in a manner that the center of the sheet thickness is exposed, and 2500 μm 2 The above region is observed. As long as the total area is 2500 μm2 The observation can be performed at a plurality of sites divided into several small regions. The step interval at the time of measurement is preferably 50 to 100 nm. From the observation data of EBSD, using a general method, the following kinds of area, KAM (Kernel Average Misorientation) value, and average crystal grain diameter are obtained.

[0191] S tot : Total area (observation area)

[0192] S tyl : Total area of oriented grains whose Taylor factor M according to the following formula (2) exceeds 2.8

[0193] S tra : Total area of oriented grains whose Taylor factor M according to the following formula (2) is 2.8 or less

[0194] S 100 : Total area of {100} oriented grains

[0195] S 110 : Total area of {110} oriented grains

[0196] K tyl : Average KAM value of oriented grains whose Taylor factor M according to the following formula (2) exceeds 2.8

[0197] K tra : Average KAM value of oriented grains whose Taylor factor M according to the following formula (2) is 2.8 or less

[0198] K 100 : Average KAM value of {100} oriented grains

[0199] K 110 : Average KAM value of {110} oriented grains

[0200] d ave : Average crystal grain diameter of the observation region

[0201] d 100 : Average crystal grain diameter of {100} oriented grains

[0202] d tyl : Average crystal grain diameter of oriented grains whose Taylor factor M according to the following formula (2) exceeds 2.8

[0203] d tra : Average crystal grain diameter of oriented grains whose Taylor factor M according to the following formula (2) is 2.8 or less

[0204] Here, the orientation allowance of the crystal grains is set to 15°. Also, the orientation allowance is set to 15° when the following oriented crystal grains occur.

[0205] Here, the Taylor factor M is a value according to the following formula (2).

[0206]

[0207] Angle between stress vector and sliding direction vector of crystal

[0208] λ: Angle between stress vector and normal vector of sliding surface of crystal.

[0209] The above Taylor factor M assumes that the sliding deformation of the crystal is caused in the sliding surface {110}, sliding direction <111>, and is a Taylor factor in the case where the in-plane strain in the plane parallel to the plate thickness direction and the rolling direction is compressed in the plate thickness direction. Hereinafter, in the Taylor factor according to formula (2), the average value calculated for all crystals that are equivalent in crystallography will be simply referred to as "Taylor factor" in the absence of a specific description.

[0210] Next, in Embodiments 1 to 3 below, the characteristics are defined by the above area, KAM value, and average crystal grain size.

[0211] Also, in the non-oriented electromagnetic steel sheet of the present embodiment, among the precipitates of one or more kinds selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, the particles having a diameter exceeding 0.5 μm are present in one or more in a field of view of 10000 μm 2 As described above, this is to further strengthen the cubic orientation at the time of strain-induced grain growth. These oxides can be determined by polishing in such a manner that the center of the plate thickness is exposed, and observing a region of 10000 μm 2 on the polished surface by EBSD.

[0212] Since the above sulfides and oxysulfides do not change due to heat treatment, in any one of the non-oriented electromagnetic steel sheets of Embodiments 1 to 3 described later, the particles having a diameter exceeding 0.5 μm are present in one or more in a field of view of 10000 μm 2 Also, the particles having a diameter exceeding 0.5 μm can be present in four or more in a field of view of 10000 μm 2 Also, the particles having a diameter exceeding 0.5 μm can be present in six or more in a field of view of 10000 μm

[0213] (Embodiment 1)

[0214] First, the metal structure of the non-oriented electromagnetic steel sheet after the surface skin pass rolling is explained. The metal structure accumulates strain enough to cause strain-induced grain growth, and can be positioned in a state of an initial stage before the strain-induced grain growth occurs. The characteristics of the metal structure of the steel sheet after the surface skin pass rolling are generally prescribed by the orientation for developing the target-oriented grains and the condition related to the strain sufficiently accumulated for the strain-induced grain growth to occur.

[0215] In the non-oriented electromagnetic steel sheet of the present embodiment, the area of the prescribed oriented grains satisfies the following equations (3) to (5).

[0216] 0.20 ≦ S tyl / S tot ≦ 0.85 … (3)

[0217] 0.05 ≦ S 100 / S tot ≦ 0.80 … (4)

[0218] S 100 / S tra ≧ 0.50 … (5)

[0219] S tyl is the amount of existence of the orientation in which the Taylor factor is sufficiently large. In the process of the strain-induced grain growth, the orientation in which the Taylor factor is small and the strain caused by the processing is difficult to accumulate is eaten away on the side of the orientation in which the Taylor factor is large and the strain caused by the processing is accumulated, and the orientation grows preferentially. Therefore, in order to develop the special orientation by the strain-induced grain growth, S tyl needs to exist in a certain degree. In the present embodiment, the area ratio S tyl / S tot is prescribed to be 0.20 or more. The area ratio S tyl / S tot is set to 0.20 or more. The area ratio S tyl / S tot of less than 0.20 does not sufficiently develop the target crystal orientation by the strain-induced grain growth. It is preferable that the area ratio S tyl / S tot be 0.30 or more, and more preferably 0.50 or more.

[0220] The upper limit of the area ratio S tyl / S tot is related to the amount of existence of the crystal orientation grain that should be developed in the process of the strain-induced grain growth as explained later, but the condition thereof is not determined only by the ratio of the preferentially grown orientation to the eaten away orientation. First, as explained later, because the area ratio S 100 / S totis 0.05 or more, so the area ratio S tyl / tot is necessarily 0.95 or less. However, if the area ratio S tyl / tot is too large, the preferential growth of the {100} oriented grains does not occur according to the correlation with the strain to be described later. The correlation with the strain will be described later in detail, but in the present embodiment, the area ratio S tyl / tot is 0.85 or less. It is preferable that the area ratio S tyl / tot be 0.75 or less, more preferably 0.70 or less.

[0221] The {100} oriented grains are preferentially grown in the strain-induced grain growth process. The {100} orientation is one of the orientations in which the Taylor factor is sufficiently small and the strain caused by working hardly accumulates, and is an orientation that can be preferentially grown in the strain-induced grain growth process. In the present embodiment, the existence of the {100} oriented grains is necessary, and in the present embodiment, the area ratio S 100 / tot of the {100} oriented grains is set to 0.05 or more. If the area ratio S 100 / tot of the {100} oriented grains is less than 0.05, the {100} oriented grains do not sufficiently develop through the strain-induced grain growth process. It is preferable that the area ratio S 100 / tot be 0.10 or more, more preferably 0.20 or more.

[0222] The upper limit of the area ratio S 100 / tot is determined according to the amount of the crystal oriented grains that should be eaten away in the strain-induced grain growth process. In the present embodiment, because the area ratio S tyl / tot of the orientations having a Taylor factor of more than 2.8, which should be eaten away in the strain-induced grain growth process, is 0.20 or more, the area ratio S 100 / tot is 0.80 or less. However, the lower the amount of the {100} oriented grains before the strain-induced grain growth process, the more remarkable the effect, and the more the {100} oriented grains can be developed. If this is taken into consideration, it is preferable that the area ratio S 100 / tot be 0.60 or less, more preferably 0.50 or less, further preferably 0.40 or less.

[0223] The {100} oriented grains are described as the orientation grains that should grow preferentially, but the same as the {100} oriented grains, the orientation grains that are small enough in Taylor factor and the strain caused by working is difficult to accumulate, and that can grow preferentially in the strain-induced grain growth are also present in a large number. Such orientation grains compete with the {100} oriented grains that should grow preferentially. On the other hand, the easy magnetization axis direction (the <100> direction) in the steel sheet plane of these orientation grains is not as many as the {100} oriented grains, and thus if these orientations develop in the strain-induced grain growth, the magnetic properties deteriorate and become poor. Therefore, in the present embodiment, the presence of the {100} oriented grains among the orientation grains that are small enough in Taylor factor is ensured.

[0224] In the present application, in the strain-induced grain growth, the area of the orientation grains that are small enough in Taylor factor and that contain the orientation grains considered to compete with the {100} oriented grains is set to S tra . Then, as shown in Equation (5), the area ratio S 100 / S tra is set to 0.50 or more, and the superiority of the growth of the {100} oriented grains is ensured. When the area ratio S 100 / S tra is less than 0.50, the {100} oriented grains do not sufficiently develop by the strain-induced grain growth. It is preferable that the area ratio S 100 / S tra be 0.80 or more, and more preferably 0.90 or more. On the other hand, the upper limit of the area ratio S 100 / S tra is not particularly limited, and the orientation grains that are small enough in Taylor factor can all be {100} oriented grains (i.e., S 100 / S tra = 1.00).

[0225] Further, in the present embodiment, the relationship with the {110} oriented grains that are known as the orientation that easily grows in the strain-induced grain growth is particularly specified. Even in the usual method of increasing the crystal grain diameter in the hot-rolled steel sheet and recrystallizing it by cold rolling, or cold rolling at a low reduction ratio, and the like, the {110} orientation is relatively easy to develop, and is an orientation that needs to be particularly considered in the competition with the {100} oriented grains that should grow preferentially. If the {110} oriented grains develop in the strain-induced grain growth, the in-plane anisotropy of the properties of the steel sheet becomes very large, and becomes poor. Therefore, in the present embodiment, it is preferable to control the area ratio S 100 / S 110 of the {100} oriented grains and the {110} oriented grains in such a manner that Equation (8) is satisfied, and the superiority of the growth of the {100} oriented grains is ensured.

[0226] S 100 / S 110 ≧1.00…(8)

[0227] In order to more reliably avoid the {110} -oriented grains from unexpectedly growing by strain-induced grain growth, the area ratio S 100 / S 110 is preferably 1.00 or more. More preferably, the area ratio S 100 / S 110 is 2.00 or more, further preferably 4.00 or more. The upper limit of the area ratio S 100 / S 110 does not need to be particularly limited, and the area ratio of the {110} -oriented grains can be zero. That is, even if the area ratio S 100 / S 110 diverges infinitely, the formula (8) is established.

[0228] The present embodiment can achieve more excellent magnetic properties by combining the strain described below in addition to the crystal orientation described above. In the present embodiment, as a provision regarding the strain, the following formula (6) needs to be satisfied.

[0229] K 100 / K tyl ≦0.990…(6)

[0230] The requirement regarding the strain is specified by the formula (6). The formula (6) is the ratio of the strain (average KAM value) accumulated in the {100} -oriented grains to the strain (average KAM value) accumulated in the oriented grains whose Taylor factor exceeds 2.8. Here, the KAM value is the orientation difference within the same grain from the adjacent measurement point, and the KAM value becomes high in a portion where the strain is large. In the view of crystallography, for example, in the case where the compression deformation in the sheet thickness direction is performed in the state of the plane strain in the plane parallel to the sheet thickness direction and the rolling direction, that is, in the case of simply rolling the steel sheet, generally, the K 100 to the K tyl ratio K 100 / K tyl is less than 1. However, in reality, the strain corresponding to the crystal orientation observed microscopically is in various forms due to the influence of the binding of the adjacent grains, the precipitates existing within the grain, and the macroscopic deformation fluctuation including the contact with the tool (rolling roll or the like) at the time of deformation. Therefore, it is difficult to appear the influence of the orientation based on the pure geometry of the Taylor factor. In addition, for example, even in the grains of the same orientation, a very large fluctuation is formed depending on the particle diameter, the shape of the particle, the orientation or the particle diameter of the adjacent grain, the state of the precipitates, the position in the sheet thickness direction, and the like. Furthermore, even in one grain, the strain distribution fluctuates greatly depending on the formation of the grain boundary vicinity and the grain, the deformation band, and the like.

[0231] In consideration of such variations, in the present embodiment, in order to obtain excellent magnetic characteristics, K 100 / K tyl is set to 0.990 or less. If K 100 / K tyl exceeds 0.990, the speciality of the region that should be eaten away is lost. Therefore, strain-induced grain growth is difficult to occur. It is preferable that K 100 / K tyl be 0.970 or less, more preferably 0.950 or less.

[0232] In competition with the {100} oriented grains that should be preferentially grown, with respect to the oriented grains having a Taylor factor of 2.8 or less, it is preferable to satisfy Equation (7).

[0233] K 100 / K tra <1.010 … (7)

[0234] The {100} oriented grains are made to preferentially grow, and it is preferable to set K 100 / K tra to less than 1.010. This K 100 / K tra is also an index of competition between the orientations in which strain is difficult to accumulate and which have a possibility of preferential growth, and K 100 / K tra is 1.010 or more, the priority of the {100} orientation in strain-induced grain growth cannot be exerted, and the target crystal orientation will not develop. K 100 / K tra is more preferably 0.970 or less, further preferably 0.950 or less.

[0235] In competition with the {100} oriented grains that should be preferentially grown, with respect to the {110} oriented grains, it is preferable to consider in the same manner as the area also in strain. In this relationship, it is preferable to control K 100 / K 110 in such a manner that Equation (9) is satisfied, and to ensure the superiority of the growth of the {100} oriented grains.

[0236] K 100 / K 110 <1.010 … (9)

[0237] In order to more reliably avoid the {110} oriented grains from unexpectedly developing through strain-induced grain growth, it is preferable to set K 100 / K 110 to less than 1.010. K 100 / K 110More preferably 0.970 or less, further preferably 0.950 or less.

[0238] In formula (9), in the absence of a crystal grain having an orientation equivalent to the denominator, no numerical-based evaluation is performed with respect to the formula, and it is considered that the formula is satisfied.

[0239] In the metal structure of the non-oriented electromagnetic steel sheet after the skin pass rolling in the present embodiment, the crystal grain size is not particularly limited. This is because, in a state where appropriate strain-induced grain growth occurs through the first heat treatment later, the relationship with the crystal grain size is not so strong. That is, with respect to whether appropriate strain-induced grain growth as a target occurs, in addition to the chemical composition of the steel sheet, the relationship of the presence amount (area) of each crystal orientation and the relationship of the strain amount of each orientation can be roughly determined.

[0240] However, when the crystal grain size is excessively coarse, although the grain growth is induced due to the strain, it is difficult to cause sufficient grain growth in a practical temperature range. In addition, when the crystal grain size is excessively coarse, it is also difficult to avoid the deterioration of the magnetic properties. Therefore, the average crystal grain size in practical use is preferably 300 μm or less. More preferably 100 μm or less, further preferably 50 μm or less, particularly preferably 30 μm or less. The finer the crystal grain size, the more easily the development of the target crystal orientation due to the strain-induced grain growth when the distribution of the crystal orientation and the strain is appropriately controlled is recognized. However, if it is excessively fine, in the processing where the strain is imparted as described above, it is difficult to form a difference in the strain amount of each crystal orientation because of the constraint with the adjacent crystal grains. From this viewpoint, the average crystal grain size is preferably 3 μm or more, more preferably 8 μm or more, further preferably 15 μm or more.

[0241] (Embodiment 2)

[0242] Next, the metal structure of the non-oriented electromagnetic steel sheet after the strain-induced grain growth occurs by further performing the first heat treatment on the non-oriented electromagnetic steel sheet after the skin pass rolling (and before the strain-induced grain growth is completed) is described. The non-oriented electromagnetic steel sheet of the present embodiment releases at least a part of the strain by the strain-induced grain growth, and the metal structure of the steel sheet after the strain-induced grain growth is defined by the crystal orientation, the strain, and the crystal grain size.

[0243] In the non-oriented electromagnetic steel sheet of the present embodiment, the area of the prescribed oriented grains satisfies the following equations (10) to (12). These prescriptions differ from the numerical ranges of the equations (3) to (5) with respect to the skin-passed non-oriented electromagnetic steel sheet described above. This is because, as the strain-induced grain growth progresses, the {100} oriented grains grow preferentially and their area increases, while the oriented grains having a Taylor factor exceeding 2.8 are mainly encroached upon by the {100} oriented grains and their area decreases.

[0244] S tyl / S tot ≦0.70 … (10)

[0245] 0.20 ≦ S 100 / S tot … (11)

[0246] S 100 / S tra ≧0.55 … (12)

[0247] Area ratio S tyl / S tot The upper limit of the area ratio S tyl / S tot exceeding 0.70 indicates that the grains of the oriented grains having a Taylor factor exceeding 2.8 are not sufficiently encroached upon and the strain-induced grain growth does not sufficiently occur. That is, since the development of the {100} oriented grains which should develop is insufficient, the magnetic properties are not sufficiently improved. Therefore, in the present embodiment, the area ratio S tyl / S tot is set to 0.70 or less. It is preferable that the area ratio S tyl / S tot be 0.60 or less, more preferably 0.50 or less. Since the area ratio S tyl / S tot is more preferable the smaller it is, it is not necessary to prescribe a lower limit and it can be 0.00.

[0248] In addition, in the present embodiment, the area ratio S 100 / S tot is set to 0.20 or more. The lower limit of the area ratio S 100 / S tot is determined as one of the parameters indicating the degree of progress of the strain-induced grain growth. When the area ratio S 100 / S tot is less than 0.20, the development of the {100} oriented grains is insufficient, and thus the magnetic properties are not sufficiently improved. It is preferable that the area ratio S 100 / S tot be 0.40 or more, more preferably 0.60 or more. Since the area ratio S 100 / S tot The higher the better, and thus an upper limit is not necessarily prescribed, and can be 1.00.

[0249] As in Embodiment 1, the relationship between the {100} -oriented grains and the {100} -oriented grains competing in strain-induced grain growth is also considered important. In the area ratio S 100 / S tot In the case of a large value, the superiority of growth of the {100} -oriented grains is ensured, and the magnetic properties are good. The area ratio S 100 / S tot A value less than 0.55 indicates that the {100} -oriented grains are not sufficiently developed by strain-induced grain growth, and the {100} -oriented grains are in a state of being encroached upon by the {100} -oriented grains having a small Taylor factor. In this case, the in-plane anisotropy of the magnetic properties also becomes large. Thus, in the present embodiment, the area ratio S 100 / S tot is set to 0.55 or more. The area ratio S 100 / S tot is preferably 0.65 or more, and more preferably 0.75 or more. On the other hand, the area ratio S 100 / S tot does not necessarily need to be particularly limited, and the {100} -oriented grains having a Taylor factor of 2.8 or less can all be {100} -oriented grains.

[0250] Further, in the present embodiment, as in Embodiment 1, the relationship with the {110} -oriented grains is also prescribed. In the present embodiment, the area ratio S 100 / S 110 of the {100} -oriented grains to the {110} -oriented grains satisfies the following equation (18), and the superiority of growth of the {100} -oriented grains is ensured.

[0251] S 100 / S 110 ≧ 1.00 … (18)

[0252] As shown in equation (18), in the present embodiment, the area ratio S 100 / S 110 is preferably 1.00 or more. The {110} -oriented grains are developed in strain-induced grain growth, and the area ratio S 100 / S 110 less than 1.00, the anisotropy in the plane of the steel sheet becomes very large, and in characteristics, it is easy to become defective. More preferably, S 100 / S 110 is 2.00 or more, and further preferably 4.00 or more. The area ratio S 100 / S 110The upper limit of K is not particularly limited, and the area ratio of the {110}-oriented grains can be zero. That is, even if the area ratio S 100 / S 110 The formula (18) is also satisfied even if the divergence is infinite.

[0253] Next, the regulation on the strain to be satisfied in the present embodiment will be described. The strain amount of the non-oriented electromagnetic steel sheet of the present embodiment is greatly reduced compared to the strain amount in the state after the skin finish rolling described in Embodiment 1, and becomes a state that is characteristic in each crystal orientation.

[0254] The regulation on the strain in the present embodiment is different in the numerical range from the formula (6) described above for the steel sheet after the skin finish rolling, and satisfies the following formula (13).

[0255] K 100 / K tyl ≦1.010…(13)

[0256] When the strain-induced grain growth sufficiently proceeds, the portion of the steel sheet where the strain is large becomes a state where it is released, the strain in each crystal orientation is homogenized, the variation of the strain becomes sufficiently small, and the ratio indicated by the formula (13) becomes a value close to 1.

[0257] On the basis of considering such variation, in the present embodiment, in order to obtain excellent magnetic characteristics, K 100 / K tyl is set to 1.010 or less. K 100 / K tyl If K exceeds 1.010, the release of the strain is not sufficient, and the reduction of the iron loss, in particular, is not sufficient. It is preferable that K 100 / K tyl be 0.990 or less, and more preferably 0.970 or less. Even if the non-oriented electromagnetic steel sheet of the present embodiment is obtained by performing the first heat treatment on the steel sheet satisfying the formula (6) described above, it is considered that the value of the formula (13) exceeds 1.000 due to the error of measurement or the like.

[0258] With respect to the relationship with the oriented grains having a Taylor factor of 2.8 or less in the competition with the {100}-oriented grains that should be preferentially grown, it is preferable to satisfy the formula (16).

[0259] K 100 / K tra <1.010…(16)

[0260] In order to make the {100}-oriented grains preferentially grow, it is preferable to set K 100 / K tra to less than 1.010. This K 100 / K traWhen K 110 is 1.010 or more, the strain is not sufficiently released, and particularly, the reduction in iron loss is not sufficient. By subjecting the non-oriented electromagnetic steel sheet satisfying the above-described formula (7) to the first heat treatment, a non-oriented electromagnetic steel sheet satisfying formula (16) is obtained.

[0261] In Embodiment 1, it is explained that the relationship with the strain of the {110} oriented grains is preferably taken into account. On the other hand, in the present embodiment, a condition in which the strain-induced grain growth is sufficiently performed and a large portion of the strain of the steel sheet is released. Therefore, K 110 , which corresponds to the strain accumulated in the {110} oriented grains, becomes a value in which the strain is released to the same degree as K 100 . As with formula (9), it is preferable that formula (19) is satisfied.

[0262] K 100 / K 110 <1.010…(19)

[0263] That is, as with formula (9), it is preferable that K 100 / K 110 is less than 1.010. K 100 / K 110 is 1.010 or more, the strain is not sufficiently released, and particularly, the reduction in iron loss is not sufficient. By subjecting the non-oriented electromagnetic steel sheet satisfying the above-described formula (9) to the first heat treatment, a non-oriented electromagnetic steel sheet satisfying formula (19) is obtained.

[0264] In formula (13) and formula (19), in the case where there is no grain having an orientation corresponding to the denominator, the evaluation based on the numerical value is not performed with respect to the formula, and it is considered that the formula is satisfied.

[0265] Next, the regulation with respect to the crystal grain diameter that should be satisfied in the present embodiment is explained. In the metal structure in the condition in which the strain-induced grain growth is sufficiently performed and a large portion of the strain is released, the crystal grain diameter of each crystal orientation has a large influence on the magnetic characteristics. The oriented grains that are primarily grown by the strain-induced grain growth become coarse, and the oriented grains that are eaten away by this become fine. In the present embodiment, the relationship of the average crystal grain diameter is set to satisfy formula (14) and formula (15).

[0266] d 100 / d ave >1.00…(14)

[0267] d 100 / d tyl >1.00…(15)

[0268] These formulas indicate that the average crystal grain diameter d 100The ratio in formula (17) is more preferably 1.30 or greater, further preferably 1.50 or greater, and particularly preferably 2.00 or greater. The upper limit of the ratio is not particularly limited, but the grains of the orientation that is encroached upon grow slowly compared to the {100} -oriented grains, and grain growth occurs in the first heat treatment, so the above ratio does not easily become excessively large, and a practical upper limit is about 10.00.

[0269] In the present embodiment, it is preferable that formula (17) be satisfied.

[0270] d 100 / d tra >1.00…(17)

[0271] This formula indicates the average crystal grain diameter d 100 The ratio in formula (17) is more preferably 1.30 or greater, further preferably 1.50 or greater, and particularly preferably 2.00 or greater. The upper limit of the ratio is not particularly limited, but the grains of the orientation that is encroached upon grow slowly compared to the {100} -oriented grains, and grain growth occurs in the first heat treatment, so the above ratio does not easily become excessively large, and a practical upper limit is about 10.00.

[0272] In addition, the range of the average crystal grain diameter is not particularly limited, but if the average crystal grain diameter becomes excessively large, it is difficult to avoid degradation of magnetic properties. Therefore, in the present embodiment, a practical average crystal grain diameter of the {100} -oriented grains, which are relatively large grains, is preferably 500 μm or less. More preferably, the average crystal grain diameter of the {100} -oriented grains is 400 μm or less, further preferably 300 μm or less, and particularly preferably 200 μm or less. On the other hand, with respect to the lower limit of the average crystal grain diameter of the {100} -oriented grains, if a state in which sufficient preferential growth of the {100} orientation is ensured is assumed, the average crystal grain diameter of the {100} -oriented grains is preferably 40 μm or greater, more preferably 60 μm or greater, and further preferably 80 μm or greater.

[0273] In formula (15), in the case where there are no grains having an orientation corresponding to the denominator, evaluation based on the numerical value is not performed with respect to the formula, and it is considered that the formula is satisfied.

[0274] (Embodiment Three)

[0275] In the above-described Embodiments 1 and 2, the strain of the steel sheet is defined by determining the KAM value as a characteristic of the steel sheet. In contrast, in the present embodiment, the steel sheet described in Embodiments 1 or 2 is sufficiently subjected to long-time annealing, and further, the steel sheet after grain growth is defined. The strain-induced grain growth of such a steel sheet is almost completed, and as a result, since the strain is almost completely released, the characteristic is very preferable. That is, the {100} -oriented grains are grown by the strain-induced grain growth, and further, the normal grains are grown to the steel sheet after the strain is almost completely released by the second heat treatment, and the steel sheet becomes one in which the aggregation to the {100} orientation is stronger. In the present embodiment, the crystal orientation and the crystal grain diameter of the steel sheet obtained by subjecting the steel sheet described in Embodiments 1 or 2 to the second heat treatment (i.e., the non-oriented electromagnetic steel sheet after the second heat treatment of the non-oriented electromagnetic steel sheet after the first heat treatment, or the non-oriented electromagnetic steel sheet after the second heat treatment with omission of the first heat treatment) are described.

[0276] The area of each of the oriented grains of the steel sheet (non-oriented electromagnetic steel sheet) obtained by the second heat treatment satisfies the following equations (20) to (22). These definitions differ in the numerical range from the equations (3) to (5) regarding the steel sheet after the skin pass rolling and the equations (10) to (12) regarding the steel sheet after the strain-induced grain growth by the first heat treatment. With the strain-induced grain growth and the subsequent second heat treatment, the {100} -oriented grains further grow and increase in area, and at the same time, the oriented grains having the Taylor factor exceeding 2.8 are mainly encroached upon by the {100} -oriented grains, and further decrease in area.

[0277] S tyl / S tot <0.55…(20)

[0278] S 100 / S tot >0.30…(21)

[0279] S 100 / S tra ≧0.60…(22)

[0280] In the present embodiment, the area ratio S tyl / S tot is set to be less than 0.55. The area ratio S tyl may be zero. The upper limit of the area ratio S tyl / S tot is determined as one of the parameters indicating the degree of progress of the growth of the {100} -oriented grains. The area ratio S tyl / S totindicating that the oriented grains whose Taylor factor exceeds 2.8 should be eaten away in the stage of strain-induced grain growth are not sufficiently eaten away. In this case, the magnetic properties are not sufficiently improved. The area ratio S tyl tot is 0.40 or less, more preferably 0.30 or less. Since the area ratio S tyl tot is smaller, it is more preferable, and thus the lower limit is not specified and can be 0.00.

[0281] In addition, in the present embodiment, the area ratio S 100 tot is set to exceed 0.30. The area ratio S 100 tot is 0.30 or less, the magnetic properties are not sufficiently improved. The area ratio S 100 tot is 0.40 or more, more preferably 0.50 or more. The area ratio S 100 tot 1.00 means a condition in which the crystal structure is entirely {100} oriented grains, and other oriented grains are not present, and the present embodiment also takes this condition as an object.

[0282] As with Embodiments 1 and 2, the relationship between the oriented grains considered to compete with the {100} oriented grains in the strain-induced grain growth and the {100} oriented grains is also important. In the present embodiment, the area ratio S 100 tra is sufficiently large, the superiority of the growth of the {100} oriented grains can be ensured even in the condition of normal grain growth after the strain-induced grain growth, and the magnetic properties are good. In this area ratio S 100 tra is less than 0.60, the {100} oriented grains do not sufficiently develop through the strain-induced grain growth, and in the condition of normal grain growth after the strain-induced grain growth, the oriented grains whose Taylor factor is small other than the {100} oriented grains grow to a considerable extent, and the in-plane anisotropy of the magnetic properties also becomes large. Thus, in the present embodiment, the area ratio S 100 tra is set to 0.60 or more. The area ratio S 100 tra is 0.70 or more, more preferably 0.80 or more. On the other hand, the area ratio S 100 tra The upper limit of the area ratio S

[0283] ​​​​​​​​​​​Even in the metal structure in a state where strain-induced grain growth and thereafter normal grain growth sufficiently proceed and the strain of the steel sheet is almost released, the crystal grain size of each crystal orientation also greatly affects the magnetic characteristics. The {100} -oriented grains that grow preferentially at the time of strain-induced grain growth become coarse grains after the normal grain growth. In the present embodiment, the relationship of the average crystal grain size is set to satisfy the formula (23) and the formula (24).

[0284] d 100 / d ave ≧ 0.95 … (23)

[0285] d 100 / d tyl ≧ 0.95 … (24)

[0286] These formulas indicate that the average crystal grain size d 100 of the {100} -oriented grains is 0.95 times or more of the average crystal grain size of the other grains. These ratios in the formula (23) and the formula (24) are preferably 1.00 or more, more preferably 1.10 or more, and further preferably 1.20 or more. The upper limit of these ratios is not particularly limited, but in the normal grain growth, the grains other than the {100} -oriented grains also grow, and at the time of entering the normal grain growth, that is, at the time of ending the strain-induced grain growth, the {100} -oriented grains become coarse, having so-called size advantage. The {100} -oriented grains are also advantageous even in the course of the normal grain growth in which they become coarse, and thus the above-described ratios sufficiently maintain the characteristics. Therefore, the practical upper limit is about 10.00. If any of these ratios exceeds 10.00, mixed grains are generated, and sometimes problems associated with the processing such as blanking are generated.

[0287] Further, in the relationship of the average crystal grain size, it is preferable to also satisfy the following formula (25).

[0288] d 100 / d tra ≧ 0.95 … (25)

[0289] This formula indicates that the average crystal grain size d 100The ratio in formula (25) is more preferably 1.00 or greater, further preferably 1.10 or greater, and particularly preferably 1.20 or greater. The upper limit of the ratio is not particularly limited, but in normal grain growth, grains other than the {100}-oriented grains also grow, and at the time of entering normal grain growth, i.e., at the time of ending strain-induced grain growth, the {100}-oriented grains become coarse and have a so-called size advantage. The {100}-oriented grains are advantageous even in the course of normal grain growth in which they become coarse, and thus the ratio is desirably maintained in a range in which characteristics are sufficiently exhibited. Thus, the practical upper limit is about 10.00. If any of these ratios exceeds 10.00, mixed grains are produced, and problems associated with punching and the like can sometimes occur.

[0290] In addition, the range of the average crystal grain diameter is not particularly limited, but if the average crystal grain diameter becomes excessively coarse, it is difficult to avoid deterioration of magnetic characteristics. Thus, as in Embodiment 2, in the present embodiment, the practical average crystal grain diameter of the {100}-oriented grains, which are relatively coarse grains, is preferably 500 μm or less. More preferably, the average crystal grain diameter of the {100}-oriented grains is 400 μm or less, further preferably 300 μm or less, and particularly preferably 200 μm or less. On the other hand, with respect to the lower limit of the average crystal grain diameter of the {100}-oriented grains, if a state in which sufficient growth of the {100} orientation is ensured is assumed, the average crystal grain diameter of the {100}-oriented grains is preferably 40 μm or greater, more preferably 60 μm or greater, and further preferably 80 μm or greater.

[0291] In formula (24), in the absence of grains having an orientation corresponding to the denominator, evaluation based on the value is not performed with respect to the formula, and it is considered that the formula is satisfied.

[0292] [Characteristics]

[0293] The non-oriented electromagnetic steel sheet of the present embodiment controls the chemical composition and the metal structure as described above, and thus can exhibit excellent magnetic characteristics not only in the average in the rolling direction and the width direction but also in the average around the entire circumference (the average in the rolling direction, the width direction, a direction at 45 degrees with respect to the rolling direction, and a direction at 135 degrees with respect to the rolling direction).

[0294] In addition, in consideration of application to a motor, it is preferable that the anisotropy of the iron loss be small. Thus, it is preferable that the ratio of W15 / 50 as the C direction (width direction) to W15 / 50 as the L direction (rolling direction), W15 / 50(C) / W15 / 50(L), be less than 1.3.

[0295] The magnetic measurement can be performed by the measurement method described in JIS C 2550-1 (2011) and JIS C 2550-3 (2019), or by the measurement method described in JIS C 2556 (2015). In addition, in a case where the sample is small and the measurement described in the above JIS cannot be performed, the electromagnetic circuit can also be measured using a device capable of measuring a 55 mm square test piece according to JIS C 2556 (2015), or a smaller test piece.

[0296] <Manufacturing method>

[0297] Next, the manufacturing method of the non-oriented electromagnetic steel sheet of the present embodiment will be described. The manufacturing method is not particularly limited, and (A) high-temperature hot-rolled sheet annealing + cold rolling strong reduction method, (B) thin slab continuous casting method, (C) lubricated hot rolling method, and (D) thin strip continuous casting method, etc. can be cited.

[0298] In any of the methods, the chemical composition of the starting material such as a slab is the above-described chemical composition.

[0299] Each manufacturing method will be described.

[0300] (A) High-temperature hot-rolled sheet annealing + cold rolling strong reduction method

[0301] First, a slab is manufactured from molten steel having the above-described chemical composition by a steel manufacturing process. Then, after heating the slab in a reheating furnace, rough rolling and finish rolling are continuously performed to obtain a hot-rolled steel sheet (hot-rolling process). The conditions in the hot-rolling process are not particularly limited, and as a general manufacturing method, the following method can also be used: first, the slab is heated to 1000 to 1200°C, and then rough rolling is performed in the hot-rolling process, finish rolling is completed at 700 to 900°C, and coiling is performed at 500 to 700°C.

[0302] Next, hot-rolled sheet annealing is performed on the hot-rolled steel sheet (hot-rolled sheet annealing process). By the hot-rolled sheet annealing, recrystallization is performed, and the grains are grown coarsely to have a crystal grain diameter of 300 to 500 μm.

[0303] The hot-rolled sheet annealing can be continuous annealing or batch annealing, but from the viewpoint of cost, it is preferable to perform the hot-rolled sheet annealing in a continuous annealing manner. In order to perform continuous annealing, it is necessary to grow the grains in a high temperature for a short time. In the case of continuous annealing, the temperature of the hot-rolled sheet annealing is set to 1000 to 1100°C, for example, and the annealing time is set to 20 seconds to 2 minutes. The non-oriented electromagnetic steel sheet of the present embodiment satisfies formula (1) in the chemical composition, and therefore even if the hot-rolled sheet annealing is performed at the above-described high temperature, ferrite-austenite phase transformation does not occur.

[0304] Next, pickling (pickling step) is performed on the steel sheet subjected to the annealing of the hot-rolled sheet before cold rolling.

[0305] The pickling is a process necessary to remove the scale on the surface of the steel sheet. The pickling conditions are selected depending on the state of scale removal. Instead of pickling, the scale can be removed by a grinder.

[0306] Next, cold rolling (cold rolling step) is performed on the steel sheet from which the scale has been removed.

[0307] Here, in the high-grade non-oriented electromagnetic steel sheet having a high Si content, if the crystal grain size is made too large, the steel sheet is embrittled, and there is a concern of brittle fracture in cold rolling. Therefore, in general, the average crystal grain size of the steel sheet before cold rolling is limited to 200 μm or less. On the other hand, in the present embodiment, annealing of the hot-rolled sheet at a high temperature is performed, and the average crystal grain size before cold rolling is made to be 300 to 500 μm. In the cold rolling step of the present embodiment, cold rolling is performed on the steel sheet having such an average crystal grain size at a reduction ratio of 88 to 97%.

[0308] From the viewpoint of avoiding brittle fracture, instead of cold rolling, warm rolling can be performed at a temperature above the ductility / brittleness transition temperature of the material.

[0309] After that, when intermediate annealing is performed under the conditions described later, the ND / / <100> recrystallized grains grow. Thereby, the {100} plane strength increases, and the existence probability of the {100} oriented grains increases.

[0310] At the end of the cold rolling, intermediate annealing (intermediate annealing step) is then performed. In the present embodiment, the intermediate annealing is performed at a temperature of 650°C or higher. If the temperature of the intermediate annealing is less than 650°C, recrystallization does not sometimes occur, the {100} oriented grains do not sufficiently grow, and the magnetic flux density does not become high. Therefore, the temperature of the intermediate annealing is set to 650°C or higher. The upper limit of the temperature of the intermediate annealing is not limited, and from the aspect of grain refinement, it can be 800°C or lower.

[0311] In addition, the annealing time is preferably set to 1 second to 60 seconds. If the annealing time is less than 1 second, the {100} oriented grains can not sufficiently grow because the time for recrystallization to occur is too short. In addition, if the annealing time exceeds 60 seconds, cost is unnecessarily spent, and therefore, it is not preferable.

[0312] At the end of the intermediate annealing, skin pass rolling (skin pass rolling step) is then performed. As described above, if the rolling is performed in a state in which the {100} oriented grains are many, the {100} oriented grains further grow. The reduction ratio of the skin pass rolling is set to 5% to 30%. If the reduction ratio is less than 5% or exceeds 30%, strain-induced grain growth does not sufficiently occur.

[0313] In the non-oriented electromagnetic steel sheet, when the distribution of the strain described above is provided, the reduction rate (%) at the time of the skin pass rolling is preferably adjusted in a manner that 5 < Rs < 20 is satisfied, in the case where Rs is provided.

[0314] After the skin pass rolling step, the non-oriented electromagnetic steel sheet of the above-described embodiment 1 is obtained.

[0315] Next, a first heat treatment for promoting strain-induced grain growth (first heat treatment step) is performed. The first heat treatment is preferably performed at 700 to 950°C for 1 second to 100 seconds.

[0316] When the heat treatment temperature is less than 700°C, strain-induced grain growth does not occur. On the other hand, when it exceeds 950°C, not only strain-induced grain growth but also normal grain growth occurs, and the metal structure described in the above-described embodiment 2 cannot be obtained.

[0317] In addition, when the heat treatment time (holding time) exceeds 100 seconds, the production efficiency is significantly reduced, and thus it is not practical. Since it is not easy to make the holding time less than 1 second in industry, the holding time is set to 1 second or more.

[0318] After the first heat treatment step, the non-oriented electromagnetic steel sheet of the above-described embodiment 2 is obtained.

[0319] A second heat treatment (second heat treatment step) is performed on the steel sheet after the skin pass rolling step or the first heat treatment step. The second heat treatment is preferably performed for 1 second to 100 seconds in the case where the temperature range is set to 950 to 1050°C, or for more than 1000 seconds in the case where the temperature range is set to 700 to 900°C.

[0320] The second heat treatment can be performed on the steel sheet on which the first heat treatment has been performed after the skin pass rolling step, or the second heat treatment can be performed after the first heat treatment is omitted after the skin pass rolling step.

[0321] By performing the heat treatment in the above-described temperature range and time, normal grain growth is performed after the strain-induced grain growth in the case where the first heat treatment is omitted, and normal grain growth is performed in the case where the first heat treatment is performed. In addition, depending on the conditions of the first heat treatment, strain-induced grain growth is sometimes also performed in the subsequent second heat treatment.

[0322] After the second heat treatment step, the non-oriented electromagnetic steel sheet of the above-described embodiment 3 is obtained.

[0323] (B) Thin Slab Continuous Casting Method

[0324] In the thin slab continuous casting method, a thin slab having a thickness of 30 to 60 mm is manufactured from molten steel having the above chemical composition by a steel manufacturing process, and the rough rolling of the hot rolling process is omitted. In this manufacturing method, it is preferable that columnar crystals be sufficiently developed in the thin slab, and that the {100} <011> oriented grains resulting from the processing of the columnar crystals by hot rolling be left in the hot rolled sheet. In this process, the columnar crystals grow with the {100} plane parallel to the surface of the steel sheet. For this purpose, it is preferable that electromagnetic stirring during continuous casting not be performed. In addition, it is preferable that the fine inclusions in the molten steel that promote the generation of solidification nuclei be reduced as much as possible.

[0325] Then, after the thin slab is heated in a reheating furnace, finish rolling is continuously performed in the hot rolling process to obtain a hot rolled sheet having a thickness of about 2 mm. Although the rough rolling is not performed, when the thin slab is heated, the heating temperature is set to, for example, 1000 to 1200°C, and thereafter, the finish rolling is completed at 700 to 900°C, and coiling is performed at 500 to 700°C.

[0326] Thereafter, the hot rolled sheet is subjected to hot sheet annealing, pickling, cold rolling, intermediate annealing, skin pass rolling, first heat treatment, and second heat treatment, similarly to the above "(A) high temperature hot rolled sheet annealing + cold rolling with high reduction method". Among these, the first heat treatment can also be omitted. In addition, as a point different from the above "(A) high temperature hot rolled sheet annealing + cold rolling with high reduction method", the reduction rate of the cold rolling is preferably set to 65 to 80%.

[0327] Through the above process, the above non-oriented electromagnetic steel sheet is obtained.

[0328] (C) lubricated hot rolling method

[0329] In the lubricated hot rolling method, a slab is first manufactured from molten steel having the above chemical composition by a steel manufacturing process. Then, after the slab is heated in a reheating furnace, rough rolling and finish rolling are continuously performed in the hot rolling process to obtain a hot rolled sheet.

[0330] Here, the hot rolling is usually performed without lubrication, but in the lubricated hot rolling method, the hot rolling is performed under appropriate lubrication conditions. When the hot rolling is performed under appropriate lubrication conditions, the shear deformation introduced into the vicinity of the surface layer of the steel sheet is reduced. Thereby, the processing structure called α fiber having RD / / <011> oriented grains that is usually developed in the center of the steel sheet can be developed to the vicinity of the surface layer of the steel sheet. For example, as described in Japanese Patent Application Publication No. 10-36912, 0.5 to 20% of oil is mixed in the hot rolling roll cooling water as a lubricant at the time of hot rolling, the average friction coefficient between the finish hot rolling roll and the steel sheet is made to be 0.25 or less, and thereby the α fiber can be developed. The temperature conditions at this time are not particularly specified, but can be the same as in the above "(A) high temperature hot rolled sheet annealing + cold rolling with high reduction method".

[0331] After that, the obtained hot-rolled steel sheet is subjected to hot-rolled sheet annealing, pickling, cold rolling, intermediate annealing, skin pass rolling, first heat treatment, and second heat treatment, similarly to the above "(A) high-temperature hot-rolled sheet annealing + cold rolling with high reduction ratio". Among them, the first heat treatment can also be omitted. In addition, as a point different from the above "(A) high-temperature hot-rolled sheet annealing + cold rolling with high reduction ratio", the reduction ratio of cold rolling is preferably set to 65 to 80%.

[0332] Through the above process, the above-described non-oriented electromagnetic steel sheet is obtained.

[0333] (D) thin strip casting method

[0334] First, in the steel manufacturing step, a steel sheet of 1 to 3 mm thickness is directly manufactured from molten steel having the above-described chemical composition by a thin strip casting method.

[0335] In the thin strip casting method, by rapidly cooling the molten steel between a pair of rolls after water cooling, a steel sheet of the above-described thickness can be obtained. At this time, by sufficiently increasing the temperature difference between the surface of the steel sheet in contact with the water-cooled roll and the molten steel, the grains that solidify on the surface grow in the vertical direction of the steel sheet, forming columnar crystals.

[0336] In a steel having a BCC structure, columnar crystals grow in a manner in which the {100} plane is parallel to the surface of the steel sheet. Due to this, the {100} plane strength increases, and the probability of existence of {100} oriented grains increases. Also, in phase transformation, processing, or recrystallization, it is important to change from the {100} plane as little as possible. Specifically, it is important to contain Si as a ferrite promoting element and limit the content of Mn as an austenite promoting element, so that an austenite phase is not generated at high temperatures, and a ferrite single phase is provided from immediately after solidification to room temperature.

[0337] Even if α-γ phase transformation occurs, a part of the {100} plane is maintained, but it is preferable to be a composition that does not cause α-γ phase transformation at high temperatures by satisfying formula (1).

[0338] Next, the steel sheet obtained by the thin strip casting method is subjected to hot rolling. After that, the obtained hot-rolled steel sheet is subjected to annealing (hot-rolled sheet annealing). It is also possible to directly perform the subsequent process without performing hot rolling and hot-rolled sheet annealing. In addition, even in the case where hot rolling is performed, it is also possible to directly perform the subsequent process without performing hot-rolled sheet annealing. Here, in the case where 30% or more of strain is introduced to the steel sheet in hot rolling, if hot-rolled sheet annealing is performed at a temperature of 550°C or higher, recrystallization sometimes occurs from the strain introduction portion, and the crystal orientation can change. Therefore, in the case where 30% or more of strain is introduced in hot rolling, hot-rolled sheet annealing is not performed or is performed at a temperature at which recrystallization does not occur (less than 550°C).

[0339] The resulting hot-rolled steel sheet is then subjected to pickling, cold rolling, intermediate annealing, skin pass rolling, a first heat treatment, and a second heat treatment, similar to the "(A) High-Temperature Hot-Rolled Sheet Annealing + Cold-Rolling Reduction Method" described above. The first heat treatment can also be omitted. Furthermore, as a difference from the "(A) High-Temperature Hot-Rolled Sheet Annealing + Cold-Rolling Reduction Method" described above, the cold rolling reduction ratio is preferably set to 65-80%.

[0340] Through the above steps, the above-mentioned non-oriented electrical steel sheet is obtained.

[0341] The non-oriented electrical steel sheet of the present embodiment can be manufactured as described above. However, this manufacturing method is just an example of a method for manufacturing the non-oriented electrical steel sheet of the present embodiment, and does not limit the manufacturing method.

[0342] Example

[0343] Next, the non-oriented electrical steel sheet of the present invention will be described in detail with reference to examples. The following examples are merely examples of the non-oriented electrical steel sheet of the present invention, and the non-oriented electrical steel sheet of the present invention is not limited to the following examples.

[0344] (First embodiment)

[0345] Molten steel was continuously cast to prepare 250 mm thick slabs having the chemical compositions shown in Table 1A below. Here, the left side of formula (1) refers to the value of the left side of the above formula (1).

[0346] Next, the slabs were hot-rolled to produce the hot-rolled sheets listed in Table 1B. The slab reheating temperature was 1200°C, the finish rolling temperature was 850°C, and the coiling temperature was 650°C. For sheets with a thickness less than 1.0 mm, a 1.0 mm sheet was produced and then ground on both sides to the target thickness.

[0347] Next, the hot-rolled sheets were annealed at 1050°C for 1 minute, pickled to remove scale, and cold rolled at the reduction ratios shown in Table 1B. Then, intermediate annealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 1B for 30 seconds, followed by a second cold rolling (skin pass rolling) at the reduction ratios shown in Table 1B.

[0348] Next, in order to investigate the texture, a part of the steel sheet was cut out, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and EBSD observation was performed on the processed surface (a surface parallel to the surface of the steel sheet) (step interval: 100 nm). The area and average KAM value of the kinds shown in Table 2 were found by the EBSD observation. Further, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more kinds of sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was also determined per 10,000 μm 2 of the surface of the steel sheet.

[0349] In addition, as the second heat treatment, annealing was performed on the steel sheet at 800°C for 2 hours.

[0350] A 55 mm square test piece was collected from the steel sheet after the second heat treatment as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45-degree inclination with respect to the rolling direction were collected. In addition, test piece collection was performed using a shearing machine. Then, the magnetic properties of the iron loss W10 / 400 (average value in the rolling direction and the width direction of the energy loss generated in the test piece when excited at a maximum magnetic flux density of 1.0 T and a frequency of 400 Hz), W10 / 400 (whole circumference) (average value in the rolling direction, the width direction, the direction at 45 degrees with respect to the rolling direction, and the direction at 135 degrees with respect to the rolling direction of the energy loss generated in the test piece when excited at a maximum magnetic flux density of 1.0 T and a frequency of 400 Hz), W15 / 50(C) (value in the width direction of the energy loss generated in the test piece when excited at a maximum magnetic flux density of 1.5 T and a frequency of 50 Hz), and W15 / 50(L) (value in the rolling direction of the energy loss generated in the test piece when excited at a maximum magnetic flux density of 1.5 T and a frequency of 50 Hz) were measured in accordance with JIS C2556 (2015). Furthermore, W15 / 50(C) was divided by W15 / 50(L) to find W15 / 50(C) / W15 / 50(L).

[0351] The measurement results are shown in Table 2.

[0352] [Table 1A]

[0353]

[0354] [Table 1B]

[0355]

[0356] [Table 2]

[0357]

[0358] Underlined conditions in Tables 1A, 1B, and 2 denote conditions outside the scope of the present invention. Inventive Examples Nos. 101 to 107, 109 to 112, 119 to 136, and 149 to 151 all had good values ​​for iron loss W10 / 400 and W10 / 400 (overall).

[0359] On the other hand, No. 108 and No. 113 to No. 117 as comparative examples do not satisfy equation (1), or any of the intermediate annealing temperature, cold rolling reduction, and skin pass rolling reduction is not optimal, and therefore do not satisfy at least one of equations (3) to (6). As a result, the iron loss W10 / 400 and W10 / 400 (overall) are high. In addition, No. 118 as comparative example does not contain any of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, so no sulfides or oxysulfides of these elements or precipitates of both are confirmed, resulting in high iron loss W10 / 400 and W10 / 400 (overall).

[0360] In Nos. 137 to 148 as comparative examples, since the chemical compositions deviated from the range of the present invention, fracture occurred during cold rolling or equations (3) and (4) were not satisfied. As a result, the iron loss W10 / 400 and W10 / 400 (entire circumference) were high.

[0361] (Second embodiment)

[0362] Molten steel was continuously cast to prepare 30 mm thick thin slabs having the chemical composition shown in Table 3A below.

[0363] Next, the thin slabs were hot-rolled to produce the hot-rolled sheets listed in Table 3B. The slab reheating temperature was 1200°C, the finish rolling temperature was 850°C, and the coiling temperature was 650°C. For sheets with a thickness less than 1.0 mm, a 1.0 mm sheet was produced and then ground on both sides to the target thickness.

[0364] Next, the hot-rolled sheets were annealed at 1000°C for 1 minute, pickled to remove scale, and cold rolled at the reduction ratios shown in Table 3B. Then, intermediate annealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 3B for 30 seconds, followed by a second cold rolling (skin pass rolling) at the reduction ratios shown in Table 3B.

[0365] Next, in order to investigate the texture, a part of the steel sheet was cut out, and the cut test piece was reduced in thickness to 1 / 2 thickness, and the processed surface was subjected to EBSD observation (step interval: 100 nm) in the above-mentioned manner. By the EBSD observation, the area of the orientation grains of the kinds shown in Table 4 and the average KAM value were calculated, and furthermore, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more kinds selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, sulfides, oxysulfides, and both of these was determined per 10,000 μm 2 .

[0366] In addition, as the second heat treatment, the steel sheet was subjected to annealing at 800°C for 2 hours. A 55 mm square test piece was collected from the steel sheet after the second heat treatment as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45-degree inclination with respect to the rolling direction were collected. In addition, the test piece collection was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (all around) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), and W15 / 50 (L) were measured in the same manner as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 4.

[0367] [Table 3A]

[0368]

[0369] [Table 3B]

[0370]

[0371] [Table 4]

[0372]

[0373] The underlines in Table 3A, Table 3B, and Table 4 indicate conditions deviating from the range of the present application. As the inventive examples, No. 201 to No. 207, No. 209 to No. 210, No. 217 to No. 235, and No. 248 to No. 250, the iron loss W10 / 400 and W10 / 400 (all around) were good values.

[0374] On the other hand, Nos. 208 and 211 to 215 as comparative examples do not satisfy the formula (1), or any one of the temperature in the intermediate annealing, the reduction rate in the cold rolling, the reduction rate in the skin pass rolling is not optimal, so that at least one of the formulae (3) to (6) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high. In addition, No. 216 as a comparative example, since it does not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, so that the precipitates of sulfides or oxysulfides or both of these elements cannot be confirmed, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0375] In Nos. 236 to 247 as comparative examples, since the chemical composition deviates from the range of the present application, so that the fracture occurs at the time of the cold rolling, or the formula (3), (4) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0376] (Third Embodiment)

[0377] The continuous casting of molten steel was performed, and a 250 mm thick slab having the chemical composition shown in Table 5A below was prepared.

[0378] Next, the above slab was subjected to hot rolling, and a 2.0 mm thick hot-rolled sheet as described in Table 5B was produced. The slab reheating temperature at this time was 1200°C, the finishing temperature in the finishing rolling was 850°C, and the coiling temperature at the time of coiling was 650°C. Further, in order to improve the lubricity with the roll at the time of the hot rolling, 10% of oil was mixed in the hot-rolling roll cooling water as a lubricant, so that the average friction coefficient between the finishing hot-rolling roll and the steel sheet was 0.25 or less. The material of the sheet thickness of less than 1.0 mm was produced by grinding both sides to the target sheet thickness after producing the material of the sheet thickness of 1.0 mm.

[0379] Next, in the above hot-rolled sheet, as the hot-rolled sheet annealing, annealing was performed at 1000°C for 1 minute, the scale was removed by pickling, and cold rolling was performed at the reduction rates shown in Table 5B. Then, intermediate annealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 5B for 30 seconds, and then, second cold rolling (skin pass rolling) was performed at the reduction rates shown in Table 5B.

[0380] Next, in order to investigate the texture, a part of the steel sheet was cut out, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation (step interval: 100 nm). By the EBSD observation, the area of the oriented grains of the kinds shown in Table 6 and the average KAM value were calculated, and furthermore, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more kinds selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, sulfides, oxysulfides, and both of these was determined per 10,000 μm 2 .

[0381] In addition, as the second heat treatment, the steel sheet was subjected to annealing at 800°C for 2 hours. A 55 mm square test piece was collected from the steel sheet after the second heat treatment as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45-degree inclination with respect to the rolling direction were collected. In addition, the test piece collection was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (all around) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), and W15 / 50 (L) were measured in the same manner as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 6.

[0382] [Table 5A]

[0383]

[0384] [Table 5B]

[0385]

[0386] [Table 6]

[0387]

[0388] The underlines in Table 5A, Table 5B, and Table 6 indicate conditions deviating from the range of the present application. As the inventive examples, No. 301 to No. 307, No. 309 to No. 310, No. 317 to No. 335, No. 348 to No. 350, the iron losses W10 / 400 and W10 / 400 (all around) were good values.

[0389] On the other hand, No. 308 and Nos. 311 to 315 as comparative examples do not satisfy the formula (1), or any one of the temperature in the intermediate annealing, the reduction rate in the cold rolling, the reduction rate in the skin pass rolling is not optimal, so that at least one of the formulae (3) to (6) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high. In addition, No. 316 as a comparative example does not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, so that the precipitates of sulfides or oxysulfides or both of these elements cannot be confirmed, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0390] In Nos. 336 to 347 as comparative examples, since the chemical composition deviates from the range of the present application, the fracture occurs at the time of the cold rolling, or the formula (3), (4) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0391] (Fourth Embodiment)

[0392] A cast slab having the chemical composition shown in Table 7A below was produced by rapidly solidifying and casting molten steel by a thin strip casting method (two-roller method). Then, in some of the cast slabs, hot rolling was performed at the time of 800°C after solidification with the reduction rates shown in Table 7B. The sheet thickness before cold rolling (the thickness of the cast slab after rapid solidification, or the material thickness after hot rolling is the material thickness after rolling) is shown in Table 7B.

[0393] Next, in the above cast slab, the oxide scale was removed by pickling, and cold rolling was performed at the reduction rates shown in Table 7B. Among them, only No. 411 was annealed as a hot rolled sheet before pickling, and annealing was performed at 1000°C for 1 minute. Then, intermediate annealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 7B for 30 seconds, and then, second cold rolling (skin pass rolling) was performed at the reduction rates shown in Table 7B.

[0394] Next, in order to investigate the texture, a part of the steel sheet was cut, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation (step interval: 100 nm). By the EBSD observation, the area of the kind of oriented grains shown in Table 8 and the average KAM value were calculated, and furthermore, the number of particles having a diameter exceeding 0.5 μm per 10000 μm 2 of the precipitates of sulfides or oxysulfides or both of these elements selected from a group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd was determined.

[0395] Further, as the second heat treatment, the steel sheet was subjected to annealing at 800°C for 2 hours. From the steel sheet after the second heat treatment, a 55 mm square test piece was collected as a measurement test piece. At this time, a test piece whose one side was parallel to the rolling direction and a test piece having a 45-degree inclination with respect to the rolling direction were collected. Further, the test piece collection was performed using a shearing machine. Then, similarly to the first embodiment, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (all around) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), W15 / 50 (L) were measured, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 8.

[0396] [Table 7A]

[0397]

[0398] [Table 7B]

[0399]

[0400] [Table 8]

[0401]

[0402] The underlines in Table 7A, Table 7B, and Table 8 indicate conditions deviating from the range of the present application. As the inventive examples, No. 401 to No. 407, No. 409 to No. 413, No. 420 to No. 438, No. 451 to No. 453, the iron losses W10 / 400, W10 / 400 (all around) were good values.

[0403] On the other hand, as the comparative examples, No. 408 and No. 414 to No. 418 did not satisfy any one of the formula (1), the temperature in the intermediate annealing, the reduction in cold rolling, the reduction in skin pass rolling, and thus did not satisfy at least one of the formula (3) to the formula (6), as a result, the iron losses W10 / 400, W10 / 400 (all around) were high. Further, as the comparative example, No. 419, since it did not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, the precipitates of sulfides or oxysulfides or both of these elements could not be confirmed, and the iron losses W10 / 400, W10 / 400 (all around) were high.

[0404] In No. 439 to No. 450 as the comparative examples, since the chemical composition deviated from the range of the present application, breakage occurred at the time of cold rolling, or the formula (3), the formula (4) was not satisfied, as a result, the iron losses W10 / 400, W10 / 400 (all around) were high.

[0405] (Fifth Embodiment)

[0406] Continuous casting of molten steel was performed to prepare a 30 mm thick thin slab having the chemical composition shown in Table 9A.

[0407] Next, the above thin slab was subjected to hot rolling to produce a hot-rolled sheet as described in Table 9B. The slab reheating temperature at this time was 1200°C, the finishing temperature in the finishing mill was 850°C, and the coiling temperature at coiling was 650°C. The material having a sheet thickness of less than 1.0 mm was produced by grinding both sides to the target sheet thickness after producing the material having a sheet thickness of 1.0 mm.

[0408] Next, in the above hot-rolled sheet, as the hot-rolled sheet annealing, annealing was performed at 1000°C for 1 minute, the scale was removed by pickling, and cold rolling was performed at the reduction ratio shown in Table 9B. Then, interannealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 9B for 30 seconds, and then, second cold rolling (skin pass) was performed at the reduction ratio shown in Table 9B.

[0409] In order to investigate the texture of the steel sheet after the skin pass, a part of the steel sheet was cut, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation (step interval: 100 nm). The area of the prescribed orientation grains and the average KAM value were found by EBSD observation, and the S tyl / S tot , S 100 / S tot , S 100 / S tra , K 100 / K tyl are shown in Table 9B.

[0410] Next, the first heat treatment was performed under the conditions shown in Table 9B.

[0411] After the first heat treatment, in order to investigate the texture, a part of the steel sheet was cut, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation. By EBSD observation, the area of the kind of orientation grains shown in Table 10A, the average KAM value, and the average crystal grain diameter were found, and furthermore, the number of particles having a diameter exceeding 0.5 μm per 10000 μm 2 of the precipitates of one or more kinds selected from the group consisting of sulfides and oxysulfides or both of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was determined.

[0412] In addition, as the second heat treatment, the steel sheet was subjected to annealing at a temperature of 800°C for 2 hours. A 55 mm square sample piece was collected from the steel sheet after the second heat treatment as a measurement sample. At this time, a sample piece whose one side was parallel to the rolling direction and a sample piece having a 45-degree inclination with respect to the rolling direction were collected. In addition, the sample piece collection was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (all around) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), W15 / 50 (L) were measured as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 10B.

[0413] [Table 9A]

[0414]

[0415] [Table 9B]

[0416]

[0417] [Table 10A]

[0418]

[0419] [Table 10B]

[0420]

[0421] The underlines in Table 9A, Table 9B, and Table 10A, Table 10B indicate conditions deviating from the range of the present application. As the inventive examples, No. 501 to No. 507, No. 509 to No. 510, No. 518 to No. 536, No. 549 to No. 552, the iron loss W10 / 400, W10 / 400 (all around) were good values.

[0422] On the other hand, as the comparative examples, No. 508 and No. 511 to No. 516 did not satisfy any one of the formula (1), the temperature in the intermediate annealing, the reduction rate in the cold rolling, the reduction rate in the skin pass rolling, the temperature in the first heat treatment, and as a result, did not satisfy at least one of the formula (10) to the formula (15), and the iron loss W10 / 400, W10 / 400 (all around) was high. In addition, as the comparative example, No. 517, since it did not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, the precipitates of sulfides or oxysulfides or both of these elements could not be confirmed, and the iron loss W10 / 400, W10 / 400 (all around) was high.

[0423] In addition, in Nos. 537 to 548 as comparative examples, since the chemical composition deviates from the range of the present application, breakage occurs at cold rolling, or the formula (10), the formula (11) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (full pitch) is high.

[0424] (Sixth Embodiment)

[0425] Continuous casting of molten steel was performed to prepare a 30 mm thick thin slab having the chemical composition shown in Table 11A.

[0426] Next, hot rolling was performed on the above thin slab to produce the hot-rolled sheet described in Table 11B. The slab reheating temperature at this time was 1200°C, the finish rolling temperature in finish rolling was 850°C, and the coiling temperature at coiling was 650°C. The material having a sheet thickness of less than 1.0 mm was produced by grinding both sides to the target sheet thickness after producing the material having a sheet thickness of 1.0 mm.

[0427] Next, in the above hot-rolled sheet, as the hot-rolled sheet annealing, annealing was performed at 1000°C for 1 minute, the scale was removed by pickling, and cold rolling was performed at the reduction ratio shown in Table 11B. Then, interannealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 11B for 30 seconds, and then, second cold rolling (skin pass) was performed at the reduction ratio shown in Table 11B.

[0428] In order to investigate the texture of the steel sheet after the skin pass, a part of the steel sheet was cut, the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the machined surface was subjected to EBSD observation (step interval: 100 nm). The area of the prescribed oriented grains and the average KAM value were found by EBSD observation, and the S tyl / S tot , S 100 / S tot , S 100 / S tra , K 100 / K tyl The results are shown in Table 11B.

[0429] Next, the second heat treatment was performed under the conditions shown in Table 11B without performing the first heat treatment. After the second heat treatment, in order to investigate the texture, a part of the steel sheet was cut, the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the machined surface was subjected to EBSD observation. By EBSD observation, the area and the average crystal grain size of the kinds shown in Table 12 were found, and furthermore, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more kinds of sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was also determined. 2 of the precipitates of one or more kinds of sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was also determined.

[0430] In addition, after the second heat treatment, a 55 mm square sample piece was collected from the steel sheet after the second heat treatment as a measurement sample. At this time, a sample piece in which one side was parallel to the rolling direction and a sample piece having a 45-degree inclination with respect to the rolling direction were collected. In addition, the sample collection was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (all around) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), and W15 / 50 (L) were measured as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 12.

[0431] [Table 11A]

[0432]

[0433] [Table 11B]

[0434]

[0435] [Table 12]

[0436]

[0437] The underlines in Table 11A, Table 11B, and Table 12 indicate conditions deviating from the range of the present application. As the inventive examples, No. 601 to No. 607, No. 609 to No. 610, No. 617 to No. 635, and 648, the iron loss W10 / 400 and W10 / 400 (all around) were good values.

[0438] On the other hand, as the comparative examples, No. 608 and No. 611 to No. 615 did not satisfy Equation (1), or any one of the intermediate annealing temperature, the reduction rate in cold rolling, and the reduction rate in skin pass rolling was not optimal, and thus did not satisfy at least one of Equations (20) to (24), as a result, the iron loss W10 / 400 and W10 / 400 (all around) were high. In addition, as the comparative example, No. 616, since it did not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, the precipitates of sulfides or oxysulfides or both of these elements could not be confirmed, and the iron loss W10 / 400 and W10 / 400 (all around) were high.

[0439] In the comparative examples No. 636 to 647, since the chemical composition deviated from the range of the present invention, fracture occurred during cold rolling or equations (20) and (21) were not satisfied. As a result, the iron loss W10 / 400 and W10 / 400 (entire circumference) were high.

[0440] (Seventh embodiment)

[0441] Molten steel was continuously cast to prepare 30 mm thick thin slabs having the chemical compositions shown in Tables 13A and 13B. These thin slabs were then hot rolled to produce the hot-rolled plates shown in Table 13C. The slab reheating temperature was 1200°C, the finishing temperature during finish rolling was 850°C, and the coiling temperature during coiling was 650°C. For plates with a thickness of less than 1.0 mm, a 1.0 mm thick plate was produced and then ground on both sides to the target thickness.

[0442] Next, the hot-rolled sheets were annealed at 1000°C for 1 minute, pickled to remove scale, and cold rolled at the reduction ratios shown in Table 13C. Then, intermediate annealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 13C for 30 seconds, followed by a second cold rolling (skin pass rolling) at the reduction ratios shown in Table 13C.

[0443] Next, a first heat treatment was performed at 800° C. for 30 seconds.

[0444] In order to evaluate the texture of the steel plate after the first heat treatment, a portion of the steel plate after the first heat treatment was cut, and the cut test piece was reduced to 1 / 2 the thickness. The processed surface was observed by EBSD (step interval: 100nm). The area of ​​the specified oriented grains, the average KAM value and the average crystal grain size were obtained through EBSD observation, and S was obtained. tyl / S tot 、S 100 / S tot 、S 100 / S tra , K 100 / K tyl d 100 / d ave d 100 / d tyl The results are shown in Table 13C.

[0445] Further, the steel sheet after the first heat treatment was subjected to a second heat treatment under the conditions shown in Table 13C. After the second heat treatment, a portion of the steel sheet was cut out, the cut-out test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation. By the EBSD observation, the area of each of the types shown in Table 14 and the average crystal grain diameter were calculated, and further, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more of the sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was determined per 10,000 μm 2 .

[0446] Further, after the above-mentioned second heat treatment, a 55 mm square test piece was collected from the steel sheet after the second heat treatment as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45-degree inclination with respect to the rolling direction were collected. Further, the test piece collection was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (whole circumference) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), and W15 / 50 (L) were measured as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 14.

[0447] [Table 13A]

[0448]

[0449] [Table 13B]

[0450]

[0451] [Table 13C]

[0452]

[0453] [Table 14]

[0454]

[0455] The underlines in Tables 13A to 13C and Table 14 indicate conditions deviating from the scope of the present application. As the inventive examples, No. 701 to No. 707, No. 709 to No. 710, No. 717 to No. 735, and No. 748, the iron losses W10 / 400 and W10 / 400 (whole circumference) were good values.

[0456] On the other hand, No. 708 and Nos. 711 to 715 as comparative examples do not satisfy the formula (1), or any one of the intermediate annealing temperature, the reduction rate in cold rolling, the reduction rate in skin pass rolling is not optimal, and therefore, at least one of the formulas (20) to (24) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high. In addition, No. 716 as a comparative example does not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, and therefore, the precipitates of sulfides or oxysulfides or both of these elements cannot be confirmed, and the iron loss W10 / 400, W10 / 400 (whole) is high.

[0457] In addition, in Nos. 736 to 747 as comparative examples, since the chemical composition deviates from the range of the present application, breakage occurs at the time of cold rolling, or the formulas (20), (21) are not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0458] (Eighth Embodiment)

[0459] A cast slab having the chemical composition shown in Tables 15A, 15B was produced by rapidly solidifying molten steel by a thin strip casting method (two-roll method) and casting, and hot rolling was performed at a reduction rate shown in Table 15C at the time when the solidification became 800°C. The thickness of the cast slab before cold rolling (the material thickness after hot rolling) is shown in Table 15C.

[0460] Next, in the above cast slab, the scale was removed by pickling, and cold rolling was performed at a reduction rate shown in Table 15C. Then, intermediate annealing was performed for 30 seconds in a non-oxidizing atmosphere at a temperature shown in Table 15C, and then, second cold rolling (skin pass rolling) was performed at a reduction rate shown in Table 15C.

[0461] Next, in order to investigate the texture of the steel sheet after the skin pass rolling, a part of the steel sheet was cut, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation (step interval: 100 nm). By the EBSD observation, the area of the prescribed orientation grains and the average KAM value were calculated, and S tyl / S tot , S 100 / S tot , S 100 / S tra , K 100 / K tyl The results are shown in Table 15C.

[0462] Next, the second heat treatment was performed under the conditions shown in Table 15C without performing the first heat treatment. After the second heat treatment, a portion of the steel sheet was cut off, the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation. By the EBSD observation, the area of each of the types shown in Table 16 and the average crystal grain diameter were calculated, and furthermore, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more of the sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was determined per 10,000 μm 2 .

[0463] In addition, after the above second heat treatment, a 55 mm square test piece was taken from the steel sheet after the second heat treatment as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45 degree inclination with respect to the rolling direction were taken. In addition, the test piece taking was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (all around) (average value of the rolling direction, the width direction, the direction having a 45 degree inclination with respect to the rolling direction, and the direction having a 135 degree inclination with respect to the rolling direction), W15 / 50 (C), and W15 / 50 (L) were measured as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 16.

[0464] [Table 15A]

[0465]

[0466] [Table 15B]

[0467]

[0468] [Table 15C]

[0469]

[0470] [Table 16]

[0471]

[0472] As the inventive examples of No. 801 to No. 831 and No. 844, the iron loss W10 / 400 and W10 / 400 (all around) were good values.

[0473] On the other hand, in No. 832 to No. 843 as comparative examples, since the chemical composition deviated from the range of the present application, the formula (20) and the formula (21) were not satisfied, and as a result, the iron loss W10 / 400 and W10 / 400 (all around) were high.

[0474] (Ninth Embodiment)

[0475] A cast slab having the chemical composition shown in Tables 17A and 17B was produced by rapidly solidifying molten steel by a thin strip casting method (twin roll method) and casting, and hot-rolled at a reduction ratio shown in Table 17C at the time when the solidification was completed at 800°C. The thickness of the cast slab before cold-rolling (the material thickness after hot-rolling) is shown in Table 17C.

[0476] Next, in the above cast slab, the oxide scale was removed by pickling, and cold-rolled at a reduction ratio shown in Table 17C. Then, interannealing was performed in an oxidation-free atmosphere at a temperature shown in Table 17C for 30 seconds, and then, second cold-rolling (skin pass) was performed at a reduction ratio shown in Table 17C.

[0477] In order to investigate the texture of the steel sheet after the skin pass, a part of the steel sheet was cut out, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation (step interval: 100 nm). From the EBSD observation, the area of the prescribed orientation grains and the average KAM value were calculated, and the S tyl / S tot , S 100 / S tot , S 100 / S tra , K 100 / K tyl value were calculated. The results are shown in Table 17C.

[0478] Next, the first heat treatment was performed under the conditions shown in Table 17C.

[0479] After the first heat treatment, in order to investigate the texture, a part of the steel sheet was cut out, and the cut test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation. From the EBSD observation, the area of the orientation grains of the kinds shown in Table 18A, the average KAM value, and the average crystal grain diameter were calculated, and furthermore, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more kinds selected from the group consisting of sulfides and oxysulfides of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd or both was determined per 10,000 μm 2 of the surface.

[0480] Further, as the second heat treatment, the steel sheet was subjected to annealing at a temperature of 800°C for 2 hours. From the steel sheet after the second heat treatment, a 55 mm square test piece was collected as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45-degree inclination with respect to the rolling direction were collected. Further, the test piece collection was performed using a shearing machine. Then, similarly to the first embodiment, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (whole circumference) (average value of the rolling direction, the width direction, the direction having a 45-degree inclination with respect to the rolling direction, and the direction having a 135-degree inclination with respect to the rolling direction), W15 / 50 (C), W15 / 50 (L) were measured, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 18B.

[0481] [Table 17A]

[0482]

[0483] [Table 17B]

[0484]

[0485] [Table 17C]

[0486]

[0487] [Table 18A]

[0488]

[0489] [Table 18B]

[0490]

[0491] In No.901 to No.913, No.915 to No.916, No.924 to No.941, No.954 to No.957 as the invention examples, in any one example, the iron loss W10 / 400, W10 / 400 (whole circumference) were good values.

[0492] On the other hand, No. 914 and No. 917 to No. 922, which are comparative examples, do not satisfy equation (1), or any of the intermediate annealing temperature, cold rolling reduction, skin pass rolling reduction, and first heat treatment temperature is not optimal, and therefore do not satisfy at least one of equations (10) to (15). As a result, the iron loss W10 / 400 and W10 / 400 (overall) are high. In addition, No. 923, which is a comparative example, does not contain any of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, and therefore no sulfides or oxysulfides of these elements, or precipitates of both, are observed, resulting in high iron loss W10 / 400 and W10 / 400 (overall).

[0493] In addition, in No. 942 to 953 as comparative examples, since the chemical composition deviates from the range of the present invention, fracture occurs during cold rolling or equations (10) and (11) are not satisfied. As a result, the iron loss W10 / 400 and W10 / 400 (entire circumference) are high.

[0494] (Tenth embodiment)

[0495] Molten steel was rapidly solidified and cast by a strip casting method (twin-roll method) to produce slabs having the chemical compositions shown in Tables 19A and 19B below. After solidification, hot rolling was performed at a temperature of 800°C at the reduction ratio shown in Table 19C. The slab thickness before cold rolling (the thickness after hot rolling) is shown in Table 19C.

[0496] Next, the cast slabs were pickled to remove scale and cold rolled at the reduction ratios shown in Table 19C. Then, intermediate annealing was performed in a non-oxidizing atmosphere at the temperature shown in Table 19C for 30 seconds, followed by a second cold rolling (skin pass rolling) at the reduction ratios shown in Table 19C.

[0497] Next, a first heat treatment was performed at 800° C. for 30 seconds.

[0498] In order to evaluate the texture of the steel plate after the first heat treatment, a portion of the steel plate after the first heat treatment was cut, and the cut test piece was reduced to 1 / 2 the thickness. The processed surface was observed by EBSD (step interval: 100nm). The area of ​​the specified oriented grains, the average KAM value and the average crystal grain size were obtained through EBSD observation, and S was obtained. tyl / S tot 、S 100 / S tot 、S 100 / S tra , K 100 / K tyl d 100 / d ave d100 / d tyl The results are shown in Table 19C.

[0499] Further, the steel sheet after the first heat treatment was subjected to a second heat treatment under the conditions shown in Table 19C. After the second heat treatment, a portion of the steel sheet was cut out, and the cut-out test piece was reduced in thickness to 1 / 2 of the thickness, and the processed surface was subjected to EBSD observation. By the EBSD observation, the area of each of the types shown in Table 20 and the average crystal grain diameter were calculated, and further, the number of particles having a diameter exceeding 0.5 μm in the precipitates of one or more of the sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd was determined per 10,000 μm 2

[0500] Further, after the above-mentioned second heat treatment, a 55 mm square test piece was collected from the steel sheet after the second heat treatment as a measurement test piece. At this time, a test piece in which one side of the test piece was parallel to the rolling direction and a test piece having a 45 degree inclination with respect to the rolling direction were collected. Further, the test piece collection was performed using a shearing machine. Then, the magnetic property iron loss W10 / 400 (average value of the rolling direction and the width direction), W10 / 400 (whole circumference) (average value of the rolling direction, the width direction, the direction having a 45 degree inclination with respect to the rolling direction, and the direction having a 135 degree inclination with respect to the rolling direction), W15 / 50 (C), and W15 / 50 (L) were measured as in the first embodiment, and W15 / 50 (C) / W15 / 50 (L) was calculated. The measurement results are shown in Table 20.

[0501] [Table 19A]

[0502]

[0503] [Table 19B]

[0504]

[0505] [Table 19C]

[0506]

[0507] [Table 20]

[0508]

[0509] As the inventive examples, No. 1001 to No. 1013, No. 1015 to No. 1016, No. 1023 to No. 1041, and No. 1054, the iron loss W10 / 400 and W10 / 400 (whole circumference) were good values.

[0510] ​On the other hand, No. 1014 and No. 1017 to No. 1021 as comparative examples do not satisfy the formula (1), or any one of the intermediate annealing temperature, the reduction rate in cold rolling, the reduction rate in skin pass rolling is not optimal, so at least one of the formula (20) to formula (24) is not satisfied, as a result, the iron loss W10 / 400, W10 / 400 (whole) is high. In addition, No. 1022 as a comparative example, since it does not contain any one of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, Cd, so as to confirm the precipitates of sulfide or oxysulfide or both of these elements, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0511] In addition, in No. 1042 to 1053 as comparative examples, since the chemical composition deviates from the scope of the present application, so that the fracture occurs during cold rolling, or does not satisfy the formula (10), formula (11), as a result, the iron loss W10 / 400, W10 / 400 (whole) is high.

[0512] In any example, the iron loss W10 / 400, W10 / 400 (whole) is a good value.

[0513] Industrial applicability

[0514] According to the present application, it is possible to provide an unoriented electromagnetic steel sheet capable of obtaining excellent magnetic properties in the whole cycle average and a manufacturing method thereof. Therefore, the industrial applicability of the present application is high.

Claims

1. A non-oriented electrical steel sheet, characterized in that: It has the following chemical composition: in mass %, contains C: 0.0100% or less, Si: 1.50% to 4.00%, One or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, and Au: less than 2.50% in total, sol.Al: 0.0001%~3.0000%, S：0.0003％～0.0100％、 N: 0.0100% or less, One or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: 0.0003% to 0.0100% in total, Cr：0.001％～0.100％、 Sn: 0.00% to 0.40%, Sb: 0.00% to 0.40%, P：0.00％～0.40％、 B: 0.0000% to 0.0050%, and O：0.0000％～0.0200％， When the Mn content is expressed as [Mn] in mass%, the Ni content is expressed as [Ni] in mass%, the Co content is expressed as [Co] in mass%, the Pt content is expressed as [Pt] in mass%, the Pb content is expressed as [Pb] in mass%, the Cu content is expressed as [Cu] in mass%, the Au content is expressed as [Au] in mass%, the Si content is expressed as [Si] in mass%, and the sol.Al content is expressed as [sol.Al] in mass%, the following formula (1) is satisfied: ([Mn]+[Ni]+[Co]+[Pt]+[Pb]+[Cu]+[Au])-([Si]+[sol.Al])≦0.00%…(1), The remainder is composed of Fe and impurities; In the precipitates of one or more sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, particles with a diameter exceeding 0.5 μm are present in the range of 10,000 μm. 2 There are more than one in the field of view; Furthermore, when observing on a plane parallel to the steel plate surface by EBSD, the total area is defined as S tot , let the area of ​​{100} oriented grains be S 100 The area of ​​oriented grains whose Taylor factor M exceeds 2.8 according to the following formula (2) is defined as S tyl The total area of ​​the oriented grains with the Taylor factor M being less than 2.8 is defined as S tra The average KAM value of the {100} oriented grains is set as K 100 The average KAM value of the oriented grains with Taylor factor M exceeding 2.8 is set as K tyl In the case of , the following equations (3) to (6) are satisfied, 0.20≦S tyl / S tot ≦0.85…(3), 0.05≦S 100 / S tot ≦0.80…(4), S 100 / S tra ≧0.50…(5), K 100 / K tyl ≦0.990…(6), Here, in formula (2) represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal.

2. The non-oriented electrical steel sheet according to claim 1, wherein Furthermore, the average KAM value of the oriented grains with the Taylor factor M being 2.8 or less is defined as K tra In the case of , the following formula (7) is satisfied: K 100 / K tra <1.010…(7)。 3. The non-oriented electrical steel sheet according to claim 1 or 2, wherein: Furthermore, when the area of ​​the {110} oriented grains is defined as S 110 In the case of , the following formula (8) is satisfied: S 100 / S 110 ≧1.00…(8), Here, even if the area ratio S 100 / S 110 If it diverges infinitely, equation (8) also holds.

4. The non-oriented electrical steel sheet according to any one of claims 1 to 3, wherein: Furthermore, when the average KAM value of {110} oriented grains is set as K 110 In the case of , the following formula (9) is satisfied: K 100 / K 110 <1.010…(9)。 5. A non-oriented electrical steel sheet, characterized in that: It has the following chemical composition: in mass %, contains C: 0.0100% or less, Si: 1.50% to 4.00%, One or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, and Au: less than 2.50% in total, sol.Al: 0.0001%~3.0000%, S：0.0003％～0.0100％、 N: 0.0100% or less, One or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: 0.0003% to 0.0100% in total, Cr：0.001％～0.100％、 Sn: 0.00% to 0.40%, Sb: 0.00% to 0.40%, P：0.00％～0.40％、 B: 0.0000% to 0.0050%, and O：0.0000％～0.0200％， When the Mn content is expressed as [Mn] in mass%, the Ni content is expressed as [Ni] in mass%, the Co content is expressed as [Co] in mass%, the Pt content is expressed as [Pt] in mass%, the Pb content is expressed as [Pb] in mass%, the Cu content is expressed as [Cu] in mass%, the Au content is expressed as [Au] in mass%, the Si content is expressed as [Si] in mass%, and the sol.Al content is expressed as [sol.Al] in mass%, the following formula (1) is satisfied: ([Mn]+[Ni]+[Co]+[Pt]+[Pb]+[Cu]+[Au])-([Si]+[sol.Al])≦0.00%…(1), The remainder is composed of Fe and impurities; In the precipitates of one or more sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, particles with a diameter exceeding 0.5 μm are present in the range of 10,000 μm. 2 There are more than one in the field of view; Furthermore, when observing on a plane parallel to the steel plate surface by EBSD, the total area is defined as S tot , let the area of ​​{100} oriented grains be S 100 The area of ​​oriented grains whose Taylor factor M exceeds 2.8 according to the following formula (2) is defined as S tyl The total area of ​​the oriented grains with the Taylor factor M being less than 2.8 is defined as S tra The average KAM value of the {100} oriented grains is set as K 100 The average KAM value of the oriented grains with Taylor factor M exceeding 2.8 is set as K tyl , the average crystal grain size of the observation area is set as d ave The average grain size of the {100} oriented grains is set to d 100 The average crystal grain size of the oriented grains with the Taylor factor M exceeding 2.8 is set as d tyl In the case of , the following equations (10) to (15) are satisfied: S tyl / S tot ≦0.70…(10), 0.20≦S 100 / S tot …(11), S 100 / S tra ≧0.55…(12), K 100 / K tyl ≦1.010…(13), d 100 / d ave >1.00…(14), d 100 / d tyl >1.00…(15), Here, in formula (2) represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal.

6. The non-oriented electrical steel sheet according to claim 5, wherein: Furthermore, the average KAM value of the oriented grains with the Taylor factor M being 2.8 or less is defined as K tra In the case of , the following formula (16) is satisfied: K 100 / K tra <1.010…(16)。 7. The non-oriented electrical steel sheet according to claim 5 or 6, wherein: Furthermore, the average crystal grain size of the oriented grains having the Taylor factor M of 2.8 or less is defined as d tra In the case of , the following formula (17) is satisfied: d 100 / d tra >1.00…(17)。 8. The non-oriented electrical steel sheet according to any one of claims 5 to 7, wherein: Furthermore, when the area of ​​the {110} oriented grains is defined as S 110 In the case of , the following formula (18) is satisfied: S 100 / S 110 ≧1.00…(18), Here, even if the area ratio S 100 / S 110 If it diverges infinitely, equation (18) also holds.

9. The non-oriented electrical steel sheet according to any one of claims 5 to 8, wherein: Furthermore, when the average KAM value of {110} oriented grains is set as K 110 In the case of , the following formula (19) is satisfied: K 100 / K 110 <1.010…(19)。 10. The non-oriented electrical steel sheet according to any one of claims 1 to 9, wherein The chemical composition, in mass%, contains Sn: 0.02% to 0.40%, Sb: 0.02% to 0.40%, and P: one or more selected from the group consisting of 0.02% to 0.40%.

11. A method for producing a non-oriented electrical steel sheet, the method for producing a non-oriented electrical steel sheet according to any one of claims 5 to 9, characterized in that: The non-oriented electrical steel sheet according to any one of claims 1 to 4 is heat-treated at a temperature of 700 to 950° C. for 1 to 100 seconds.

12. A non-oriented electromagnetic steel sheet, characterized in that: It has the following chemical composition: in mass %, contains C: 0.0100% or less, Si: 1.50% to 4.00%, One or more selected from the group consisting of Mn, Ni, Co, Pt, Pb, Cu, and Au: less than 2.50% in total, sol.Al: 0.0001%~3.0000%, S：0.0003％～0.0100％、 N: 0.0100% or less, One or more selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: 0.0003% to 0.0100% in total, Cr：0.001％～0.100％、 Sn: 0.00% to 0.40%, Sb: 0.00% to 0.40%, P：0.00％～0.40％、 B: 0.0000% to 0.0050%, and O：0.0000％～0.0200％， When the Mn content is expressed as [Mn] in mass%, the Ni content is expressed as [Ni] in mass%, the Co content is expressed as [Co] in mass%, the Pt content is expressed as [Pt] in mass%, the Pb content is expressed as [Pb] in mass%, the Cu content is expressed as [Cu] in mass%, the Au content is expressed as [Au] in mass%, the Si content is expressed as [Si] in mass%, and the sol.Al content is expressed as [sol.Al] in mass%, the following formula (1) is satisfied: ([Mn]+[Ni]+[Co]+[Pt]+[Pb]+[Cu]+[Au])-([Si]+[sol.Al])≦0.00%…(1), The remainder is composed of Fe and impurities; In the precipitates of one or more sulfides or oxysulfides or both selected from the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd, particles with a diameter exceeding 0.5 μm are present in the range of 10,000 μm. 2 There are more than one in the field of view; Furthermore, when observing on a plane parallel to the steel plate surface by EBSD, the total area is defined as S tot , let the area of ​​{100} oriented grains be S 100 The area of ​​oriented grains whose Taylor factor M exceeds 2.8 according to the following formula (2) is defined as S tyl The total area of ​​the oriented grains with the Taylor factor M being less than 2.8 is defined as S tra , the average crystal grain size of the observation area is set as d ave The average grain size of the {100} oriented grains is set to d 100 The average crystal grain size of the oriented grains with the Taylor factor M exceeding 2.8 is set as d tyl In the case of , the following equations (20) to (24) are satisfied, S tyl / S tot <0.55…(20), S 100 / S tot >0.30…(21), S 100 / S tra ≧0.60…(22), d 100 / d ave ≧0.95…(23), d 100 / d tyl ≧0.95…(24), Here, in formula (2) represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal.

13. The non-oriented electrical steel sheet according to claim 12, wherein: Furthermore, when the average crystal grain size of the oriented grains having the Taylor factor M of 2.8 or less is set to d tra In the case of , the following formula (25) is satisfied: d 100 / d tra ≧0.95…(25)。 14. A method for manufacturing a non-oriented electrical steel sheet, characterized in that: The non-oriented electrical steel sheet according to any one of claims 1 to 10 is heat treated at 950 to 1050°C for 1 to 100 seconds or at 700 to 900°C for more than 1000 seconds.

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