Non-aggregate electrical steel with very good all-round performance and manufacturing methods for it.

Abstract

Invention details;

Description

Non-oriented electrical steel with excellent comprehensive performance and manufacturing method thereof Technical Field

[0001] The present invention relates to a steel plate and a manufacturing method thereof, and in particular to a non-oriented electrical steel plate and a manufacturing method thereof. Background Art

[0002] With the rapid development of electric vehicles, higher requirements are being placed on non-oriented silicon steel, the magnetic core material of the drive motor, its core component. The non-oriented silicon steel must have sufficiently high strength to withstand centrifugal forces at high speeds to ensure that the rotor does not deform or break. At the same time, it must have excellent electromagnetic properties, especially the iron loss in the high-frequency range of 400Hz-2000Hz must be as low as possible, and the magnetic induction intensity must be high to meet the high torque requirements during motor starting or acceleration.

[0003] The Chinese patent document with publication number CN101490294A and publication date of July 22, 2009, entitled “High Strength Non-Oriented Magnetic Steel Sheet”, discloses a non-oriented electrical steel sheet with a strength exceeding 650 MPa. Although the strength is high, the iron loss P of the electromagnetic steel sheet is 10 / 400 As high as 70W / kg, poor electromagnetic performance.

[0004] The Chinese patent document, CN112930412A, published on June 8, 2021, and titled "Non-oriented electromagnetic steel sheet, method for manufacturing the same, and electric iron core and method for manufacturing the same," discloses a non-oriented electrical steel sheet with excellent strength and iron loss. The main solution is to anneal cold-rolled steel sheets with a Si content of 2.8-6.5% at 700-820°C, strengthening them through a non-completely recrystallized structure with a recrystallization area ratio of 40-95%, resulting in a yield strength exceeding 500 MPa. However, this method cannot simultaneously meet the high-frequency, low iron loss, and high magnetic flux density requirements of the drive motor.

[0005] Based on this, it is expected to obtain a non-oriented electrical steel with excellent comprehensive performance and a manufacturing method thereof, which has high strength and excellent electromagnetic properties.

[0006] Summary of the Invention

[0007] One of the objectives of the present invention is to provide a non-oriented electrical steel with excellent comprehensive performance. The non-oriented electrical steel has small magnetic anisotropy, high magnetic induction intensity, low medium and high frequency iron loss, and high yield strength. The steel can be widely used in core materials such as electric vehicle drive motors, high-speed motors, and drones.

[0008] In order to achieve the above object, the present invention provides a non-oriented electrical steel comprising, in addition to Fe and unavoidable impurities, the following chemical elements in mass %:

[0009] C≤0.0050%, Si: 3.10-4.50%, Al: 0.10-2.00%, Mn: 0.10-2.50%; and 3.75%≤Si+Al≤5.22%, preferably 3.75%≤Si+Al≤5.00%;

[0010] Preferably, the present invention provides a non-oriented electrical steel containing the following chemical elements in mass %:

[0011] C≤0.0050%, Si: 3.10-4.50%, Al: 0.10-2.00%, Mn: 0.10-2.50%, and the balance is Fe and inevitable impurities; and satisfies 3.75%≤Si+Al≤5.22%, preferably satisfies 3.75%≤Si+Al≤5.00%.

[0012] In the non-oriented electrical steel of the present invention, the design principles of each chemical element are as follows:

[0013] C: In the non-oriented electrical steel of the present invention, C is an impurity element, which is harmful to the magnetic properties of the non-oriented silicon steel. Therefore, the C content must be strictly controlled to C≤0.0050%, for example, C≤0.0042%, C≤0.0030%.

[0014] Si: In the non-oriented electrical steel described in the present invention, Si can increase the resistivity of the non-oriented electrical steel sheet and reduce the iron loss. At the same time, as a solid solution strengthening element, it can also improve the strength of the steel sheet. When the Si content exceeds 4.50%, ordered phases Fe3Si or FeSi will appear, and the room temperature plasticity of the material will deteriorate sharply, making it impossible to carry out industrial large-scale cold rolling production. At the same time, the magnetic induction strength will also deteriorate. When the Si content is less than 3.10%, the effects of high yield strength, high frequency and low iron loss cannot be achieved. Based on this, the Si element content is controlled within a range of 3.10-4.50%. For example, the upper limit of the Si content can be 4.00%, 3.78%, etc., and the lower limit of the Si content can be 3.25%, etc.

[0015] Al: In the non-oriented electrical steel described in the present invention, Al is also an effective element for increasing resistivity and reducing iron loss. However, excessive addition is detrimental to the material's magnetic induction strength, making steelmaking and casting difficult, and deteriorating the cold working properties of the steel plate. Therefore, the addition level is controlled to no more than 2.00%. Furthermore, considering the element's role in improving iron loss, the addition level is controlled to be above 0.10%. Therefore, the Al content is controlled within a range of 0.10-2.00%. For example, the upper limit of the Al content can be 1.50%, 1.35%, etc., and the lower limit of the Al content can be 0.15%, 0.50%, 0.65%, etc.

[0016] Furthermore, the present invention specifically controls the total content of the alloying elements Si and Al to 3.75%-5.22%, preferably 3.75%-5.00%. This is because both elements are solid solution strengthening elements and increase the material's resistivity. If the total content is less than 3.75%, the performance of the non-oriented silicon steel sheet of the present invention cannot be achieved. Exceeding 5.22% will cause difficulties in cold rolling production and reduce magnetic induction. For example, the upper limit of the Si+Al content can be 5.00%, 4.80%, etc., and the lower limit of the Si+Al content can be 3.95%, 4.10%, etc.

[0017] Mn: In the non-oriented electrical steel described herein, Mn increases resistivity and reacts with the impurity element S to form MnS, improving electromagnetic properties. Therefore, the addition of 0.10% or more Mn is necessary, while exceeding 2.50% reduces the steel's plasticity and can lead to strip breakage during cold rolling. Therefore, the Mn content is controlled to 0.10-2.50%, preferably 0.10-2.00%. For example, the upper limit of the Mn content can be 1.84%, 1.51%, etc., while the lower limit of the Mn content can be 0.15%, 0.35%, 0.65%, etc.

[0018] Preferably, the C element content is C≤0.0030%.

[0019] Preferably, among the inevitable impurities, P≤0.040%, S≤0.0030%, N≤0.0050%, O≤0.0030%, and Nb+V+Ti≤0.0050%.

[0020] More preferably, among the inevitable impurities, P≤0.020%, and N≤0.0035%.

[0021] In the non-oriented electrical steel of the present invention, the elements P, S, N, O, Nb, V and Ti are all impurity elements. If technical conditions permit, in order to obtain steel with better performance and better quality, the content of impurity elements in the steel should be reduced as much as possible. Among them:

[0022] P: P is a grain boundary segregating element. For a composition system with a Si content exceeding 3.10%, such as the present invention, a phosphorus content exceeding 0.040% can exacerbate the brittleness of the electrical steel sheet and make rolling difficult. For example, the P content can be ≤ 0.034%, ≤ 0.024%, or ≤ 0.020%.

[0023] S: In the present invention, S is a magnetically detrimental element. It combines with Mn to form fine MnS, which hinders grain growth during final annealing and degrades the magnetic properties of the steel sheet. Therefore, the S content by mass is controlled to: S ≤ 0.0030%. For example, S ≤ 0.0018%, S ≤ 0.0015%, etc.

[0024] N: In the present invention, N is a magnetically detrimental element. It forms fine nitrides with Al, Ti, Nb, and V, hindering grain growth. Therefore, in the non-oriented electrical steel described herein, the mass percentage of N is controlled to: N ≤ 0.0050%. For example, N ≤ 0.0035% and N ≤ 0.0015%.

[0025] O: In the present invention, O is a harmful element. For a composition system where 3.75% ≤ Si + Al ≤ 5.22%, the material's cold working properties are very sensitive to grain boundary oxygen segregation. Furthermore, the resulting silicon, aluminum, and manganese oxides can also degrade the material's magnetic properties. Therefore, in the present invention, the mass percentage of O is controlled to: O ≤ 0.0030%. For example, O ≤ 0.0021% and O ≤ 0.0015%.

[0026] Nb, V, and Ti will combine with residual C and N in the steel to form fine carbides and nitrides, which seriously affect grain growth during the annealing process and are detrimental to the magnetic properties of the material. Therefore, the present invention controls the total mass percentage content of the three elements Nb, V, and Ti to be below 0.0050%, for example, below 0.0045% or below 0.0035%.

[0027] Preferably, the non-oriented electrical steel of the present invention further contains B: 0.0003-0.0100%.

[0028] In the above technical solution of the present invention, in order to further optimize the performance of the non-oriented electrical steel of the present invention, an appropriate amount of element B may be preferably added to the steel.

[0029] B: In the non-oriented electrical steel described herein, B is a grain-boundary strengthening element, enhancing the grain-boundary bonding ability of high-silicon systems, thereby improving the material's cold-rolling performance. However, excessive B addition can refine the grain structure, negatively impacting magnetic properties. Therefore, its content should not exceed 0.0100% by weight. Furthermore, a B content below 0.0003% in the steel fails to provide grain-boundary strengthening. For example, the upper limit of the B content can be 0.0080%, and the lower limit can be 0.0010%.

[0030] Preferably, the non-oriented electrical steel of the present invention contains at least one of Sn and Sb, and the total content of Sn and Sb is 0.005-0.300%. For example, the total content of Sn and Sb can be 0.010-0.300%.

[0031] Sn and Sb are both grain boundary segregation elements. On the one hand, they can hinder the diffusion of trace oxygen along the grain boundaries during the normalizing annealing process of hot-rolled plates, preventing oxidation and plastic degradation in the steel plates. On the other hand, they can improve the magnetically favorable textures such as the {100} plane texture and Goss texture in the annealing process of the finished plates.

[0032] Preferably, the non-oriented electrical steel of the present invention further contains at least one of Co, Ni, Cu, and Cr, and the total weight percentage of these elements is controlled within a range of 0.02-3.00%. For example, the total weight percentage of Co, Ni, Cu, and Cr may be 0.30-3.00%, such as 0.40-2.00%.

[0033] Elements such as Co, Ni, Cu, and Cr can play a role in solid solution strengthening. These elements can further improve the electromagnetic properties and strength of the material without damaging the cold working performance of the steel plate.

[0034] Preferably, the average grain size of the non-oriented electrical steel of the present invention is 10-110 μm, preferably 35-98 μm.

[0035] If the grain size of the finished plate is less than 10 μm, the iron loss P of the present invention cannot be achieved. 10 / 600 Performance requirements: If the grain size of the finished plate exceeds 110μm, the yield strength will be reduced, and the production efficiency will be low, the production equipment requirements will be high, and the cost will increase.

[0036] Preferably, the non-oriented electrical steel according to the present invention has a thickness of 0.10 to 0.30 mm, for example, 0.15 to 0.30 mm.

[0037] The non-oriented electrical steel of the present invention has excellent comprehensive properties, including high strength, low iron loss, high magnetic induction and low magnetic anisotropy.

[0038] Preferably, the yield strength of the non-oriented electrical steel of the present invention is ≥430 MPa, preferably ≥455 MPa.

[0039] Preferably, the iron loss P of the non-oriented electrical steel of the present invention at a magnetic flux density of 1.0T and a frequency of 600Hz is 10 / 600 ≤35.0W / kg (preferably P 10 / 600 ≤29.3W / kg), magnetic induction intensity B 50 ≥1.640T(preferably B 50 ≥1.654T), and the longitudinal magnetic induction intensity B 50L and transverse magnetic induction intensity B 50C The difference ΔB does not exceed 1000 Gauss (preferably ΔB does not exceed 822 Gauss).

[0040] Accordingly, another object of the present invention is to provide a method for manufacturing the above-mentioned non-oriented electrical steel. The manufacturing method is simple and feasible, and can obtain non-oriented electrical steel sheets with excellent comprehensive properties.

[0041] In order to achieve the above object, the present invention provides a method for producing non-oriented electrical steel, which comprises the following steps:

[0042] (1) obtaining a casting blank;

[0043] (2) Hot rolling: The final rolling reduction rate of the rough rolling is controlled to be 35%-55%. The intermediate slab obtained by the rough rolling is kept warm for 50s-80s before entering the finishing mill. The temperature of the intermediate slab when entering the finishing mill is 960-1100°C (preferably 965-1100°C). The temperature difference ΔT between the beginning and the end of the intermediate slab is ≤40°C (preferably ≤35°C).

[0044] (3) Normalizing annealing;

[0045] (4) Cold rolling;

[0046] (5) Final annealing;

[0047] (6) Apply insulation coating.

[0048] Preferably, in step (2), the {001} surface texture strength of the intermediate slab before entering the finishing mill at a distance of one quarter of the slab surface thickness is equal to that of the {111} <112> Texture intensity ratio I≥0.55.

[0049] In the present invention, the inventors optimized the chemical composition design of the steel and defined a reasonable manufacturing process. After the continuous casting billet is produced according to the designed chemical composition, it is sequentially subjected to hot rolling, normalizing annealing, cold rolling (which can be a single cold rolling or a double cold rolling with intermediate annealing), final annealing and coating with an insulating coating to obtain non-oriented electrical steel with excellent comprehensive performance.

[0050] Preferably, when the continuous casting slab is subjected to hot rough rolling, the reduction rate of the last rolling pass is controlled to be 35-55% to obtain an intermediate slab. Before entering the hot finishing mill, the intermediate slab needs to stay on a roller with an insulation cover for 50-80 seconds, or it can also be re-coiled and uncoiled using the hot coil box equipment after the roughing mill to achieve an insulation stay of 50-80 seconds. The temperature of the intermediate slab entering the first stand of the finishing mill is controlled at 960-1100°C, and the temperature difference ΔT between the head and tail of the intermediate slab is ≤40°C.

[0051] The above process parameters are limited mainly to make the intermediate slab fully recrystallized, reduce the solid solution precipitation of second phases such as AlN, MnS, and TiC, increase the magnetically favorable texture components, and especially control the {001} plane texture strength at a quarter of the distance from the surface of the intermediate slab to make it consistent with the {111} <112> The texture intensity ratio I≥0.55, thereby improving the texture effect of the finished annealed plate, reducing the magnetic anisotropy, and the longitudinal magnetic induction intensity B 50L and transverse magnetic induction intensity B50C The difference ΔB does not exceed 1000 Gauss, and the magnetic induction intensity B 50 Technical effects exceeding 1.64T.

[0052] In addition, the temperature difference between the head and tail of the intermediate slab is controlled within 40°C. On the one hand, it can ensure the consistency of the performance of the entire coil of strip steel products. On the other hand, it can realize constant speed and constant temperature rolling of the subsequent finishing rolling mill, greatly reducing the risk of motor overcurrent when the finishing mill produces thin-gauge, high-grade non-oriented silicon steel, and ensuring the stability of continuous production.

[0053] Preferably, in step (2), the thickness of the intermediate slab obtained by rough rolling is 25-40 mm.

[0054] Preferably, in step (3), the normalizing temperature is 850-1050° C., and the normalizing holding time is, for example, 90 seconds.

[0055] Preferably, in step (5), the final annealing temperature is 750-1000° C., and the final annealing time is 11 s-125 s.

[0056] The final annealing process is designed to better achieve the target grain size of the finished non-oriented electrical steel sheet of 10-110 μm. If the annealing temperature is too low or the annealing time is too short, the grain size of the finished sheet will be less than 10 μm, and the iron loss P of the present invention will not be achieved. 10 / 600 Performance requirements, but the annealing temperature is too high or the annealing time is too long, causing the grain size of the finished steel plate to exceed 110μm, the yield strength will be reduced, and the production efficiency will be low and the cost will increase.

[0057] The non-oriented electrical steel and the method for manufacturing the same according to the present invention have the following advantages and beneficial effects:

[0058] The non-oriented electrical steel of the present invention has small magnetic anisotropy, high magnetic induction intensity, low medium and high frequency iron loss, and high yield strength, and can be widely used in core materials such as electric vehicle drive motors, high-speed motors, and drones.

[0059] Preferably, the yield strength of the non-oriented electrical steel of the present invention is ≥430MPa (preferably ≥455MPa), and the iron loss P 10 / 600 ≤35.0W / kg (preferably P 10 / 600 ≤29.3W / kg), magnetic induction intensity B 50 ≥1.640T(preferably B 50 ≥1.654T), and the longitudinal magnetic induction intensity B 50L and transverse magnetic induction intensity B 50C The difference ΔB does not exceed 1000 Gauss (preferably ΔB does not exceed 822 Gauss).

[0060] Unless otherwise expressly stated or there is an obvious contradiction, the endpoint values ​​of the ranges described herein can be arbitrarily combined to generate another range or sub-range. For example, in some embodiments, the upper limit value described for a certain feature can also be used as the lower limit value of the feature; and the lower limit value described for a certain feature can also be used as the upper limit value of the feature. DETAILED DESCRIPTION

[0061] The non-oriented electrical steel and the manufacturing method thereof according to the present invention will be further explained and illustrated below in conjunction with specific embodiments. However, such explanation and illustration do not constitute an undue limitation to the technical solution of the present invention.

[0062] Examples 1-10 and Comparative Examples 1-5

[0063] Table 1 lists the mass percentage of each chemical element in the finished electrical steels of Examples 1-10 and Comparative Examples 1-5.

[0064] The non-oriented electrical steels of Examples 1-10 were prepared by the following steps:

[0065] (1) Molten steel is smelted and cast to produce ingots.

[0066] (2) Hot rolling (including rough rolling and finishing rolling): The final rolling reduction of the rough rolling is controlled at 35%-55% to obtain an intermediate slab with a thickness of 25-40 mm. The intermediate slab is kept warm for 50s-80s before entering the finishing mill. The {001} surface texture strength of the intermediate slab at a quarter of the thickness of the slab surface before entering the finishing mill is the same as that of the {111} <112> The texture strength ratio I is ≥ 0.55; the temperature of the intermediate slab when entering the finishing mill is 960-1100°C, and the temperature difference ΔT between the head and tail of the intermediate slab is controlled to be ≤ 40°C.

[0067] (3) Normalizing annealing: The normalizing temperature of Examples 1-4 is 1050°C, the normalizing temperature of Examples 5-7 is 920°C, and the normalizing temperature of Examples 8-10 is 850°C; the normalizing temperature of Comparative Examples 1-5 is 920°C; the normalizing holding time of Examples 1-10 and Comparative Examples 1-5 is 90s.

[0068] (4) Cold rolling: The steel is rolled into the target thickness through one cold rolling process, or rolled into a plate with a thickness of 0.10 to 0.30 mm through one cold rolling process + intermediate annealing + secondary cold rolling.

[0069] (5) Final annealing: The final annealing temperature is 750-1000°C, and the final holding time is 11s-125s.

[0070] (6) Apply insulation coating.

[0071] It should be noted that although Comparative Examples 1-5 were also prepared using the above-mentioned steps and processes, one or more of their specific process parameters and / or chemical element compositions did not meet the control requirements of the present invention.

[0072] Table 2 lists the specific manufacturing process parameters and final product thicknesses of the electrical steels of Examples 1-10 and Comparative Examples 1-5.

[0073] The finished electrical steels of Examples 1-10 and Comparative Examples 1-5 were sampled and tested for iron loss P at a magnetic flux density of 1.0 T and a frequency of 600 Hz. 10 / 600 , magnetic induction intensity B when magnetized under a magnetic field of 5000A / m 50 , longitudinal magnetic induction intensity B 50L and the transverse magnetic induction intensity B 50L The test results of the steel and the yield strength are listed in Table 3. The relevant performance test methods are as follows:

[0074] The grain size of the finished plate is measured based on the planimetric method of the standard GB / T6394-2017 Determination of average grain size of metals.

[0075] Iron loss P 10 / 600 The test is based on the square circle method of the standard "GB / T10129-2019 Measurement method of medium frequency magnetic properties of electrical steel strip (sheet)".

[0076] The magnetic induction intensity is based on the square circle method of the standard "GB / T3655-2008 Method for measuring the magnetic properties of electrical steel sheets (strips) using Epstein square circles", and the B 50 , vertical B 50L Horizontal B 50C .

[0077] The yield strength performance index is based on the standard "GB / T 228.1-2010 Metallic materials tensile tests Part 1: Room temperature test method".

[0078] Table 3 lists the test results of the finished electrical steels of Examples 1-10 and Comparative Examples 1-5.

[0079] Table 3

[0080] From Table 1, Table 2, and Table 3 above, it can be seen that in Comparative Examples 1 and 2, the Si content is not within the scope of the present invention, resulting in the grain size of the finished product of Comparative Example 1 exceeding the upper limit and its yield strength being low, while also resulting in the iron loss of Comparative Example 2 being relatively high.

[0081] The Si content in Comparative Example 3 does not meet the requirements of the present invention, and the Si+Al content is less than 3.75%, resulting in a low yield strength.

[0082] Although the compositions of Comparative Examples 4 and 5 meet the requirements of the present invention, their hot rolling process parameters and texture ratio I are not within the specified ranges, and therefore the desired finished product magnetic induction intensity and magnetic anisotropy of the present invention are not obtained.

[0083] Embodiment 1-2 of the present invention adopts a single cold rolling process, and its chemical composition control, the reduction rate of the last rough rolling pass, the holding residence time, the temperature of the intermediate slab entering the finishing mill, the temperature difference between the head and tail of the intermediate slab, and the finished product grain size are all within the design range of the present invention, so that non-oriented silicon steel with high yield strength, excellent magnetic properties and excellent comprehensive performance can be obtained.

[0084] In Example 2 of the present invention, Sn and Sb are further added, and its strength and iron loss are better than those of Example 1.

[0085] In Example 3 of the present invention, B is further added, and its strength and iron loss are also better than those of Example 1.

[0086] In Examples 4-9 of the present invention, the performance of the finished steel plates is further improved by further adding at least one of the microalloying elements Sn, Sb, Co, Ni, Cu, and Cr and performing a secondary cold rolling process.

[0087] In Example 10 of the present invention, microalloying elements such as Co, Ni, Cu, and Cr are further added, and its strength and iron loss are better than those of Example 1.

[0088] It should be noted that the prior art within the scope of protection of the present invention is not limited to the embodiments given in this application document. All prior art that does not contradict the solutions of the present invention, including but not limited to prior patent documents, prior publications, prior public uses, etc., can be included in the scope of protection of the present invention.

[0089] In addition, the combination of the various technical features in this case is not limited to the combination described in the claims of this case or the combination described in the specific embodiments. All technical features recorded in this case can be freely combined or combined in any way unless there is a contradiction between them.

[0090] It should also be noted that the embodiments listed above are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or modifications made therefrom that can be directly derived from or easily conceived by those skilled in the art based on the disclosure of the present invention are intended to fall within the scope of protection of the present invention.

Claims

DEPCT6925 / 09 / 25681. Non-sorted grain electrical steel containing the following chemical elements in percentage by mass, excluding Fe and unavoidable impurities: C less than or equal to 0.0050%, Si: 3.10-4.50%, Al: 0.10-2.00%, Mn: 0.10-2.50%; and corresponding to 3.75% less than or equal to Si + Al less than or equal to 5.22%, desirable is 3.75% less than or equal to Si + Al less than or equal to 5.00%.

2. Butt electrical steel. Non-sorted grain electrical steel, according to claim 1, contains the following chemical elements in percentage by mass: C less than or equal to 0.0050 percent, Si: 3.10-4.50 percent, Al: 0.10-2.00 percent, Mn: 0.10-2.50 percent, and the remainder is Fe and unavoidable impurities; and corresponds to 3.75 percent less than or equal to Si + Al less than or equal to 5.22 percent, the desirable being 3.75 percent less than or equal to Si + Al less than or equal to 5.00 percent.

4. Non-grained electrical steel according to Requisition 1 or 2 where C is less than or equal to 0.0030 percent.

5. Non-grained electrical steel according to Requisition 1 or 2 where in the unavoidable impurities P is less than or equal to 0.040 percent, S is less than or equal to 0.0030 percent, N is less than or equal to 0.0050 percent, O is less than or equal to 0.0030 percent, and Nb+V+Ti is less than or equal to 0.0050 percent.

4. Where P is less than or equal to 0.020 percent, N is less than or equal to 0.0035 percent.

6. Non-grained electrical steel according to Requisition 1 or 2 where the non-grained electrical steel is further composed of B: 0.0003-0.0100 percent.

7. Non-grained electrical steel according to Requisition 1 or 2 where the steel is further composed of at least one element of choice from Sn and Sb, and the total amount of Sn and Sb in percentage by mass is 0.005-0.300 percent. 8.Non-sorted grain electrical steel according to Reservation 1 or 2, where the non-sorted grain electrical steel is further composed of at least one selected element from Co, Ni, Cu, and Cr, and the total amount of Co, Ni, Cu, and Cr in percentage by mass is 0.02-3.00 percent, preferably 0.30-3.00 percent.

9. Non-sorted grain electrical steel according to Reservation 1 or 2, where the non-sorted grain electrical steel has an average grain size of 10-110 micrometers.

10. Non-sorted grain electrical steel according to Reservation 1 or 2...

11. Non-sorted grain electrical steel according to Reputation 1 or 2, where the non-sorted grain electrical steel has a yield strength greater than or equal to 430 MPa, core loss P10 / 600 less than or equal to 35.0 W / kg, magnetic induction intensity B50 greater than or equal to 1.640 Tesla, and the difference Delta B between the longitudinal magnetic induction intensity B50L and the transverse magnetic induction intensity B50C is not greater than 1000 Gauss. 12.The method for producing non-sorted grain electrical steel under any of the claims 1-11 consists of the following steps: (1) preparation of flat billets from casting; (2) hot rolling: the final channel reduction rate in the initial hot rolling is 35-55 percent, heating of the intermediate billets obtained by the initial hot rolling for 50-80 seconds before entering the finishing roll; the temperature of the intermediate billets is 960-1100 °C and the temperature difference (delta T) between the head and tail of the intermediate billets is less than or equal to 40 °C when entering the finishing roll; (3) normal annealing; (4) cold rolling; (5) final annealing; (6) coating of insulating coating.

13. The method under claim 12 in which step (2) the ratio I of the texture strength in the plane {001} to the texture strength {111} <112> It is greater than or equal to 0.55 at a position within the intermediate flat bar where the distance from the flat bar surface is one-quarter of the flat bar thickness before entering the finishing roll forming machine.14Method according to claim 12 in which in step (2) intermediate flat bars obtained by initial hot rolling have a thickness of 25-40 mm.

15. Method according to claim 12 in which in step (3) normal annealing is performed at a temperature of 850-1050 °C.

16. Method according to claim 12 in which in step (5) final annealing is performed at a temperature of 750-1000 °C. for 11-125 seconds;