Non-oriented electrical steel plate with excellent assembly performance and manufacturing method thereof

Abstract

The invention discloses a non-oriented electrical steel plate with excellent assembly performance, which contains Fe and inevitable impurities, and also contains the following chemical elements in percentage by mass: less than or equal to 0.005% of C, 1.0-4.0% of Si, 0.1-2.0% of Mn, more than 0 and less than or equal to 1.8% of Al, at least one of less than or equal to 0.5% of Sn and less than or equal to 0.5% of Sb, and the balance of Fe and inevitable impurities. And the mass percentage content of each chemical element also meets the condition that 0.6 * Si + 5 * Sn + 5 * Sb-0. 3 * Mn-0. 5 * Al is greater than or equal to 0. The invention also discloses a manufacturing method of the steel plate. The manufacturing method comprises the following steps: smelting and casting; hot rolling; normalizing is conducted; cold rolling; and carrying out continuous annealing and insulating coating, wherein the continuous annealing temperature is 700-1100 DEG C. According to the non-oriented electrical steel plate and the manufacturing method thereof, the non-oriented electrical steel plate has a proper thermal expansion coefficient and good electromagnetic performance, and the non-oriented electrical steel plate with excellent assembly performance can be obtained.

Description

Technical Field

[0001] This invention relates to a steel plate and a method for manufacturing the same, and more particularly to a non-oriented electrical steel plate and a method for manufacturing the same. Background Technology

[0002] For the stator and rotor of drive motors in new energy vehicles, the air gap size is a crucial design parameter. The air gap size significantly impacts the motor's performance and operational reliability: when the air gap is too large, excitation losses increase, the excitation current also increases, and the motor's power factor decreases, thus degrading the motor's performance. When the air gap is too small, not only does the air gap harmonic magnetic field increase, but stray losses also increase, affecting the motor's performance. Furthermore, a too-small air gap affects the assembly precision of the stator and rotor, making it prone to rotor-stator rubbing during operation, causing a "steering" phenomenon that poses a serious safety hazard and significantly reduces the drive motor's operational reliability.

[0003] Non-oriented silicon steel sheets are important soft magnetic materials used in the manufacture of electric motors and generators. Due to the spatial constraints of automotive interiors, drive motors experience poor heat dissipation and operate at temperatures far higher than conventional motors. Non-oriented silicon steel undergoes greater thermal expansion at high temperatures, leading to a smaller air gap between the stator and rotor, which negatively impacts the performance of the drive motor's stator and rotor. Therefore, non-oriented silicon steel requires superior thermal expansion properties to achieve good motor assembly precision. Existing patent literature relates to the above-mentioned technical field.

[0004] For example, Chinese patent document CN111654130A, published on September 11, 2020, entitled "A Composite Rotor Structure for a High-Speed ​​Permanent Magnet Synchronous Motor with an Energy Storage Flywheel," discloses a composite rotor structure for a high-speed permanent magnet synchronous motor with an energy storage flywheel. This structure mainly includes a rotor shaft, permanent magnets, sector-shaped interpole filler, a high-temperature alloy fastening sleeve, an annular silicon steel core shielding sleeve, and a carbon fiber fastening sleeve. However, this patent document uses expensive and technologically immature carbon fiber to fix the silicon steel sheets and control the air gap size. Furthermore, its manufacturing process is cumbersome and complex, unsuitable for large-scale production, and it does not address the material properties of non-oriented silicon steel. Summary of the Invention

[0005] One of the objectives of this invention is to provide a non-oriented electrical steel sheet with excellent assembly performance. By optimizing its chemical composition design, the non-oriented electrical steel sheet can obtain a suitable coefficient of thermal expansion and a non-oriented silicon steel sheet with excellent assembly performance, while also possessing good electromagnetic properties.

[0006] To achieve the above objectives, the present invention provides a non-oriented electrical steel sheet with excellent assembly performance, which contains Fe and unavoidable impurities, and also contains the following chemical elements in the following mass percentages:

[0007] C≤0.005%, Si:1.0-4.0%, Mn:0.1-2.0%, 0<Al≤1.8%, and at least one of Sn and Sb, wherein Sn≤0.5% and Sb≤0.5%;

[0008] Furthermore, the mass percentage content of each chemical element satisfies the following condition: 0.6×Si+5×Sn+5×Sb-0.3×Mn-0.5×Al≥0.

[0009] The inventors discovered through research that the coefficient of thermal expansion of a single-phase homogeneous solid solution alloy composed of metallic and non-metallic elements in non-oriented silicon steel lies between the coefficients of thermal expansion of the internal components. In contrast, the coefficient of thermal expansion of multi-element alloys depends on the properties and quantities of the constituent elements and can be approximated by calculating the mass percentage of each element using the mixing rule. Therefore, to effectively control the linear coefficient of thermal expansion of non-oriented silicon steel and achieve the technical effect of non-oriented silicon steel with excellent assembly performance, this invention optimizes the combination of chemical element types and contents in non-oriented silicon steel and balances the relationship between the contents of each alloy, limiting the element synergy relationship to satisfy: 0.6×Si+5×Sn+5×Sb-0.3×Mn-0.5×Al≥0, where each chemical element is represented by its mass percentage value before the percentage sign.

[0010] Furthermore, in the non-oriented electrical steel sheet described in this invention, the mass percentage content of each chemical element is as follows:

[0011] C ≤ 0.005%, Si: 1.0-4.0%, Mn: 0.1-2.0%, 0 < Al ≤ 1.8%, and at least one of Sn and Sb, wherein Sn ≤ 0.5% and Sb ≤ 0.5%; the balance being Fe and unavoidable impurities.

[0012] In the non-oriented electrical steel sheet with excellent assembly performance described in this invention, the design principles of each chemical element are as follows:

[0013] C: In the non-oriented silicon steel sheet of this invention, carbon (C) strongly hinders grain growth in the finished strip, and it also readily combines with impurities Nb, V, and Ti to form fine precipitates, thereby increasing losses and causing magnetic aging. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of C is controlled below 0.0050%.

[0014] Si: In the non-oriented silicon steel sheet of this invention, when the mass percentage of Si is too low, the steel sheet cannot obtain excellent thermal expansion and electromagnetic properties; when the mass percentage of Si is too high, it will reduce the cold workability of the steel sheet. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of Si is controlled between 1.0% and 4.0%. In some embodiments, the mass percentage of Si can be further controlled between 1.0% and 3.6%.

[0015] Mn: In the non-oriented silicon steel sheet of this invention, Mn can react with the impurity element S to form MnS, which can prevent the hot brittleness caused by the formation of low-melting-point FeS along the grain boundaries. Since Mn is a metallic element with a high coefficient of thermal expansion, an excessively high mass percentage of Mn will lead to an excessively high coefficient of thermal expansion in the silicon steel. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of Mn is controlled between 0.1% and 2.0%.

[0016] Al: In the non-oriented silicon steel sheet of the present invention, since Al is a metallic element with a high coefficient of thermal expansion, an excessively high mass percentage of Al will lead to an excessively high coefficient of thermal expansion of the silicon steel. Therefore, in the non-oriented silicon steel sheet of the present invention, the mass percentage of Al is controlled between 0 < Al ≤ 1.8%.

[0017] Sn and Sb: In the non-oriented silicon steel sheet of this invention, Sn and Sb elements can promote favorable crystal texture growth, improve magnetic induction, and reduce iron loss. When the mass percentage content of Sn and Sb elements is too high, it will lead to grain refinement and abnormal segregation. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage content of Sn element is controlled between Sn ≤ 0.5%, and the mass percentage content of Sb element is controlled between Sb ≤ 0.5%.

[0018] Furthermore, the non-oriented electrical steel sheet of the present invention also contains at least one of the following chemical elements in mass percentage:

[0019] 0 < Ge ≤ 0.01%;

[0020] 0 < Bi ≤ 0.01%;

[0021] 0 < Ca ≤ 0.01%;

[0022] 0 < Mg ≤ 0.01%;

[0023] 0 < REM ≤ 0.01%.

[0024] In the non-oriented silicon steel sheet of this invention, Ge element can significantly improve the proportion of favorable crystal texture. However, excessively high Ge element mass percentages will significantly increase the manufacturing cost of the steel sheet. Therefore, in the non-oriented silicon steel sheet of this invention, the Ge element mass percentage can be controlled to 0 < Ge ≤ 0.01%.

[0025] In the non-oriented silicon steel sheet of this invention, Bi can significantly improve the proportion of favorable crystal texture. However, excessively high Bi content leads to severe grain refinement. Therefore, in the non-oriented silicon steel sheet of this invention, the Bi content can be controlled to 0 < Bi ≤ 0.01%.

[0026] In the non-oriented silicon steel sheet of this invention, calcium (Ca) can improve the cleanliness of the steel and promote grain growth. However, excessively high Ca content leads to a significant increase in manufacturing costs. Therefore, in the non-oriented silicon steel sheet of this invention, the Ca content can be controlled to 0 < Ca ≤ 0.01%.

[0027] In the non-oriented silicon steel sheet of this invention, magnesium (Mg) can improve the cleanliness of the steel and promote grain growth. However, when the mass percentage of Mg is too high, it leads to grain refinement and reduced iron loss. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of Mg can be controlled to 0 < Mg ≤ 0.01%.

[0028] In the non-oriented silicon steel sheet of this invention, REM can improve the cleanliness of the steel and promote grain growth. However, excessively high REM content leads to a significant increase in manufacturing costs. Therefore, in the non-oriented silicon steel sheet of this invention, the REM content can be controlled to 0 < REM ≤ 0.01%.

[0029] Furthermore, the non-oriented electrical steel sheet of the present invention also contains at least one of the following chemical elements in mass percentage:

[0030] 0 < Cr ≤ 3.0%;

[0031] 0 < Ni ≤ 5.0%;

[0032] 0 < Cu ≤ 2.0%

[0033] In the non-oriented silicon steel sheet of this invention, chromium (Cr) can increase resistivity and reduce eddy current loss and high-frequency iron loss. However, when the mass percentage of Cr is too high, it will reduce the magnetic flux density of the steel sheet and increase the cost. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of Cr can be controlled to 0 < Cr ≤ 3.0%.

[0034] In the non-oriented silicon steel sheet of this invention, Ni can increase the resistivity of silicon steel, thereby reducing iron loss, without decreasing the saturation magnetic flux density. However, when the mass percentage of Ni is too high, the cost of the steel sheet increases significantly. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of Ni can be controlled to 0 < Ni ≤ 5.0%.

[0035] In the non-oriented silicon steel sheet of this invention, Cu can increase resistivity. However, when the mass percentage of Cu is too high, it leads to a decrease in magnetic flux density and an increase in cost. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of Cu can be controlled to 0 < Cu ≤ 2.0%.

[0036] Furthermore, in the unavoidable impurities of the non-oriented electrical steel sheet of the present invention, the content of each impurity element satisfies at least one of the following: P≤0.15%, S≤0.003%, N≤0.003%, Ti≤0.003%.

[0037] In the above technical solution, P, S, N, and Ti are all impurity elements in steel. When technical conditions permit, to obtain steel with better performance and higher quality, the content of impurity elements in the steel should be reduced as much as possible. Specifically:

[0038] In the non-oriented silicon steel sheet of this invention, an excessively high mass percentage of phosphorus (P) will lead to a decrease in the cold-rolling stability of the steel sheet. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage of P can be controlled to P ≤ 0.15%.

[0039] In the non-oriented silicon steel sheet of this invention, when the mass percentage content of sulfur (S) is too high, it significantly increases sulfide inclusions and inhibits grain growth. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage content of sulfur can be controlled to S ≤ 0.003%.

[0040] In the non-oriented silicon steel sheet of this invention, when the mass percentage content of nitrogen (N) is too high, it significantly increases nitride inclusions and inhibits grain growth. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage content of nitrogen can be controlled to N ≤ 0.003%.

[0041] In the non-oriented silicon steel sheet of this invention, when the mass percentage content of Ti is too high, it will significantly increase nitride inclusions and inhibit grain growth. Therefore, in the non-oriented silicon steel sheet of this invention, the mass percentage content of Ti can be controlled to Ti ≤ 0.003%.

[0042] Furthermore, the non-oriented electrical steel sheet of the present invention has a linear thermal expansion coefficient α < 15 × 10⁻⁶ in the temperature range of 20–200°C. -6 (1 / K).

[0043] The inventors discovered through research that when the linear thermal expansion coefficient α exceeds 15 × 10⁻⁶, -6 When the temperature range is (1 / K), the desired change rate of the stator-rotor air gap in the drive motor cannot be obtained. Therefore, in this invention, the linear thermal expansion coefficient α in the temperature range of 20 to 200°C can be controlled to α < 15 × 10⁻⁶. -6 (1 / K).

[0044] Furthermore, the iron loss P of the non-oriented electrical steel sheet described in this invention... 10 / 700 ≤120W / kg.

[0045] Another object of the present invention is to provide a method for manufacturing non-oriented electrical steel sheet, which obtains non-oriented silicon steel sheet with excellent assembly performance by controlling process parameters.

[0046] To achieve the above objectives, the present invention provides a method for manufacturing non-oriented electrical steel sheets, comprising the following steps:

[0047] Smelting and casting;

[0048] Hot-rolled;

[0049] Normalization;

[0050] Cold rolling;

[0051] Continuous annealing and insulating coating: the continuous annealing temperature is 700~1100℃.

[0052] In this invention, in order to achieve recrystallization of the steel sheet structure, the annealing temperature needs to be higher than the recrystallization temperature. Therefore, in this invention, the continuous annealing temperature is controlled at 700–1100°C.

[0053] Furthermore, in the continuous annealing step of the manufacturing method described in this invention, the annealing time is 10 to 100 seconds.

[0054] Furthermore, in the manufacturing method described in this invention, the cold rolling step includes: primary cold rolling, intermediate annealing, and secondary cold rolling, wherein the cumulative reduction rate of the secondary cold rolling is 45-75%.

[0055] In some embodiments of the present invention, the reduction rate of the secondary cold rolling process has a significant impact on the texture. In order to improve the texture and thus improve the electromagnetic properties, the cumulative reduction rate of the secondary cold rolling process can be controlled to 45-75%.

[0056] The non-oriented electrical steel sheet with excellent assembly performance and its manufacturing method described in this invention have the following advantages and beneficial effects:

[0057] The non-oriented electrical steel sheet with excellent assembly performance and its manufacturing method described in this invention can obtain a suitable coefficient of thermal expansion and good electromagnetic properties by optimizing its chemical composition design and process parameters, thereby obtaining a non-oriented silicon steel sheet with excellent assembly performance.

[0058] In some embodiments, the non-oriented electrical steel sheet with excellent assembly performance described in this invention has a linear coefficient of thermal expansion α < 15*10⁻⁶ in the temperature range of 20–200°C. -6 (1 / K), iron loss P 10 / 700 ≤120W / kg. Attached Figure Description

[0059] Figure 1 The diagram schematically illustrates the relationship between the linear thermal expansion coefficient α of the non-oriented silicon steel described in this invention and the dimensional change rate of the stator and rotor air gap of a permanent magnet synchronous motor made from the non-oriented silicon steel in the temperature range of 20-200℃. Detailed Implementation

[0060] The following description, in conjunction with the accompanying drawings and specific embodiments, will further explain and illustrate the non-oriented electrical steel sheet with excellent assembly performance and its manufacturing method as described in this invention. However, this explanation and description do not constitute an undue limitation on the technical solution of this invention.

[0061] Examples 1-7 and Comparative Examples 1-3

[0062] The non-oriented electrical steel sheets with excellent assembly performance in Examples 1-7 of this invention are all prepared using the following steps:

[0063] (1) Smelting and casting: After the molten iron in the blast furnace undergoes molten iron pretreatment, converter smelting, RH refining and continuous casting, a continuous casting billet with a thickness of 300mm is obtained.

[0064] (2) Hot rolling: The heating temperature can be controlled at 1080℃ and the holding time can be controlled at 2 hours.

[0065] (3) Normalization: The final rolling temperature of the steel coil can be controlled at 820℃ and the coiling temperature can be controlled at 600℃ to obtain a hot-rolled plate with a thickness between 1.5-2.5mm.

[0066] (4) Cold rolling: Examples 1-4 use a two-stage cold rolling process, which involves intermediate annealing and a second cold rolling after the first cold rolling. The cumulative reduction rate of the second cold rolling can be 45-75%. Examples 5-7 use a one-stage cold rolling process, which directly rolls the product to the desired thickness.

[0067] (5) Continuous annealing and insulating coating: The continuous annealing temperature is 700-1100℃ and the annealing time can be controlled to be 10-100s.

[0068] It should be noted that although the comparative steels of Comparative Examples 1-3 were also prepared using the above steps, their chemical composition ratios and process parameters did not meet the design requirements of this invention.

[0069] Tables 1-1, 1-2, and 1-3 list the mass percentage of each chemical element in the non-oriented electrical steel sheets with excellent assembly performance of Examples 1-7 and the comparative steels of Comparative Examples 1-3.

[0070] Table 1-1. (wt%, balance Fe and other unavoidable impurities other than P, S, N and Ti)

[0071] serial number C Si Mn Al Sn Sb 0.6×Si+5×Sn+5×Sb-0.3×Mn-0.5×Al Example 1 0.0018 1.1 0.35 1.1 0.45 0 2.26 Example 2 0.0024 3.3 0.55 0.4 0 0.03 1.77 Example 3 0.0048 3.9 0.35 1.80 0.1 0 1.84 Example 4 0.0011 3.4 1.5 0.25 0 0.1 1.97 Example 5 0.0025 2.8 0.11 0.77 0.3 0.48 5.16 Example 6 0.0009 3.1 1.9 0.003 0.1 0 1.79 Example 7 0.0012 2.6 0.12 0.25 0.2 0.05 2.65 Comparative Example 1 0.0011 0.8 1.2 0.8 0.02 0 -0.18 Comparative Example 2 0.0018 1.9 1.9 1.8 0 0 -0.33 Comparative Example 3 0.0024 3.4 0.05 1.3 0 0.6 4.38

[0072] Table 1-2. (wt%, balance Fe and other unavoidable impurities other than P, S, N and Ti)

[0073]

[0074]

[0075] Table 1-3. (wt%, balance Fe and other unavoidable impurities besides P, S, N and Ti)

[0076] serial number Cr Ni Cu P S N Ti Example 1 0 0 0 0.002 0.0021 0.0018 0.0002 Example 2 2.99 0.02 0.05 0.15 0.003 0.0003 0.001 Example 3 0.05 2.85 0.001 0.01 0.0025 0.0012 0.0005 Example 4 1.2 0.001 1.96 0.06 0.0018 0.003 0.001 Example 5 0.03 1.19 0.02 0.04 0.0007 0.0008 0.0008 Example 6 2.1 4.98 0.14 0.002 0.0002 0.0012 0.0003 Example 7 0.04 0.35 0.005 0.03 0.0016 0.0002 0.003 Comparative Example 1 0.12 1.82 0.08 0.11 0.0035 0.0013 0.0005 Comparative Example 2 0.19 0.38 0.37 0.07 0.0026 0.0028 0.0005 Comparative Example 3 0.02 0.77 2.1 0.02 0.0006 0.0007 0.0016

[0077] Table 2 lists the specific process parameters of the non-oriented electrical steel sheets with excellent assembly performance in Examples 1-7 and the comparative steels in Comparative Examples 1-3.

[0078] Table 2.

[0079]

[0080] Note: In the table, " / " indicates that only one cold rolling process is used, and the product is rolled directly to the finished thickness.

[0081] Samples were taken from the non-oriented electrical steel sheets with excellent assembly performance obtained in Examples 1-7 and the control steels of Comparative Examples 1-3, and their relevant properties were tested. The results of the relevant performance tests are listed in Table 3. The specific testing methods for the relevant properties are as follows:

[0082] Iron loss performance testing: Based on the national standard GB / T10129-2019 "Method for Measurement of Medium Frequency Magnetic Properties of Electrical Steel Strips (Sheets)", the Epstein square ring method was used for iron loss performance testing. The test temperature was a constant temperature of 20℃, the sample size was 30mm×300mm, the target mass was 0.25kg, and the test parameter was P. 10 / 700 .

[0083] Linear thermal expansion coefficient test: The linear thermal expansion coefficient of the steel plate in the temperature range of 20 to 200℃ is tested using the push rod method in accordance with the national standard GB / T 4339-2008. The test equipment can be the Linseis L75VS1400C / 500LT thermal expansion meter.

[0084] Stator-rotor air gap size change rate test: Measured using a feeler gauge. Insert the feeler gauge between the stator and rotor cores, and measure the air gap size by adjusting the tightness of the feeler gauge. Measurements are typically taken at four points on the stator and rotor (top, bottom, left, and right), with a minimum of three points required to ensure data accuracy.

[0085] Table 3 lists the test results of various properties of the non-oriented electrical steel sheets with excellent assembly performance in Examples 1-7 and the comparative steels in Comparative Examples 1-3.

[0086] Table 3.

[0087]

[0088] As can be seen from Table 3 above, the non-oriented electrical steel sheets of Examples 1-7, which are manufactured using the manufacturing method described in this invention and exhibit excellent assembly performance, have a linear thermal expansion coefficient α of less than 15 × 10⁻⁶ in the temperature range of 20–200°C, due to the unique composition and process design of this invention. -6 (1 / K), while its iron loss P 10 / 700 All values ​​are less than 120W / kg, thus exhibiting good electromagnetic properties and excellent assembly performance.

[0089] Furthermore, as can be seen from Table 3, the change rate of the stator and rotor air gap dimensions of the permanent magnet synchronous motors made of non-oriented silicon steel in Examples 1-7 is less than 1%.

[0090] In addition, the inventors also experimentally determined the correlation between the dimensional change rate of the stator and rotor air gap of the prototype permanent magnet synchronous motor in the temperature range of 20-200℃ and the linear thermal expansion coefficient α of non-oriented silicon steel. The parameters of the prototype permanent magnet synchronous motor are: outer diameter 200mm, inner diameter 170mm, stack thickness 120mm, rated power 160KW, and maximum torque 300Nm.

[0091] Figure 1The diagram schematically illustrates the relationship between the linear thermal expansion coefficient α of the non-oriented silicon steel described in this invention and the dimensional change rate of the stator and rotor air gap of a permanent magnet synchronous motor made from the non-oriented silicon steel in the temperature range of 20-200℃.

[0092] from Figure 1 It can be seen that when the linear thermal expansion coefficient α is greater than 15 × 10 in the temperature range of 20–200℃, -6 When (1 / K), the change rate of the stator and rotor air gap size of the permanent magnet synchronous motor will be greater than 1%.

[0093] It should be noted that the combination of the technical features in this case is not limited to the combination methods described in the claims of this case or the combination methods described in the specific embodiments. All technical features described in this case can be freely combined or combined in any way, unless they contradict each other.

[0094] 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 thereto are those that can be directly derived or easily conceived by those skilled in the art from the content disclosed in the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A non-oriented electrical steel sheet with excellent assembly performance, containing Fe and unavoidable impurities, characterized in that, It also contains the following chemical elements in the following percentages by mass: C≤0.005%, Si:1.0-4.0%, Mn:0.1-2.0%, 0<Al≤1.8%, and at least one of Sn and Sb, wherein Sn≤0.5% and Sb≤0.5%; Furthermore, the mass percentage content of each chemical element satisfies the following condition: 0.6×Si+5×Sn+5×Sb-0.3×Mn-0.5×Al≥0.

2. The non-oriented electrical steel sheet as described in claim 1, characterized in that, Its mass percentage content of each chemical element is as follows: C ≤ 0.005%, Si: 1.0-4.0%, Mn: 0.1-2.0%, 0 < Al ≤ 1.8%, and at least one of Sn and Sb, wherein Sn ≤ 0.5% and Sb ≤ 0.5%; the balance being Fe and unavoidable impurities.

3. The non-oriented electrical steel sheet as described in claim 1 or 2, characterized in that, It also contains at least one of the following chemical elements in the following mass percentages: 0 < Ge ≤ 0.01%; 0 < Bi ≤ 0.01%; 0 < Ca ≤ 0.01%; 0 < Mg ≤ 0.01%; 0 < REM ≤ 0.01%.

4. The non-oriented electrical steel sheet as described in claim 1 or 2, characterized in that, It also contains at least one of the following chemical elements in the following mass percentages: 0＜Cr≤3.0％； 0 < Ni ≤ 5.0%; 0 < Cu ≤ 2.0% 5. The non-oriented electrical steel sheet as described in claim 1 or 2, characterized in that, Among the unavoidable impurities, the content of each impurity element must satisfy at least one of the following conditions: P≤0.15%, S≤0.003%, N≤0.003%, Ti≤0.003%.

6. The non-oriented electrical steel sheet as described in claim 1 or 2, characterized in that, Its linear thermal expansion coefficient α in the temperature range of 20 to 200℃ is <15×10 -6 (1 / K).

7. The non-oriented electrical steel sheet as described in claim 1 or 2, characterized in that, Its iron loss P 10 / 700 ≤120W / kg.

8. The method for manufacturing non-oriented electrical steel sheet according to any one of claims 1-7, characterized in that, Including the following steps: Smelting and casting; Hot-rolled; Normalization; Cold rolling; Continuous annealing and insulating coating: the continuous annealing temperature is 700~1100℃.

9. The manufacturing method as described in claim 8, characterized in that, In the continuous annealing step, the annealing time is 10 to 100 seconds.

10. The manufacturing method as described in claim 8, characterized in that, The cold rolling process includes: primary cold rolling, intermediate annealing, and secondary cold rolling, wherein the cumulative reduction rate of the secondary cold rolling is 45-75%.

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