WO2025242032A1 - Non-oriented electrical steel sheet having excellent punchability and manufacturing method therefor - Google Patents

Abstract

Disclosed in the present invention is a non-oriented electrical steel sheet having excellent punchability. In addition to Fe and inevitable impurities, the non-oriented electrical steel sheet further contains the following chemical elements in percentage by mass: greater than 0% and less than or equal to 0.004% of C, 1.6-3.4% of Si, 0.05-0.50% of Mn, 0.02-0.10% of P, greater than 0% and less than or equal to 0.50% of Al, 0.0003-0.0040% of Ca, and 0.01-0.20% of Cr, wherein the total of Si and Al is 1.8 to 3.6%. Further disclosed in the present invention is a manufacturing method for the non-oriented electrical steel sheet. The non-oriented electrical steel sheet of the present invention not only has low iron loss and high magnetic induction, but also exhibits excellent punchability.

Description

A non-oriented electrical steel sheet with excellent punching properties and its manufacturing method Technical Field

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

Various motors, compressors, and drive motors are major consumers of electrical energy. In order to minimize the power consumption of electrical appliances, the non-oriented electrical steel sheet used to make the iron core of electrical appliances needs to have low iron loss, high magnetic induction, and good punching performance.

However, it is difficult to simultaneously achieve optimal iron loss, magnetic properties, and stamping performance. Generally, adding large amounts of alloying elements such as Si, Mn, and Al to steel can significantly reduce iron loss in non-oriented electrical steel sheets, but this also drastically reduces the material's magnetic properties. Simultaneously, the material's mechanical properties increase, deteriorating its stamping performance.

Summary of the Invention

One of the objectives of this invention is to provide a non-oriented electrical steel sheet with excellent punching processability. This non-oriented electrical steel sheet, obtained by optimizing the chemical composition of the steel, not only has excellent magnetic properties but also excellent punching processability.

To achieve the above objectives, the present invention provides a non-oriented electrical steel sheet with excellent punching processability, which, in addition to containing Fe and unavoidable impurities, also contains the following chemical elements in the following mass percentages:

0 < C ≤ 0.004%, Si: 1.6–3.4%, Mn: 0.05–0.50%, P: 0.02–0.10%, 0 < Al ≤ 0.50%, Ca: 0.0003–0.0040%, Cr: 0.01–0.20%; of which Si + Al totals 1.8–3.6%.

Preferably, the mass percentage content of each chemical element in the non-oriented electrical steel sheet of this disclosure is as follows:

0 < C ≤ 0.004%, Si: 1.6–3.4%, Mn: 0.05–0.50%, P: 0.02–0.10%, 0 < Al ≤ 0.50%, Ca: 0.0003–0.0040%, Cr: 0.01–0.20%; the balance is Fe and unavoidable impurities.

The total content of Si and Al is 1.8% to 3.6%.

Preferably, the non-oriented electrical steel sheet of this disclosure further contains at least one of the following chemical elements in the following mass percentages: 0 < Ge ≤ 0.02%; 0 < Bi ≤ 0.01%; 0 < REM ≤ 0.02%.

Preferably, the non-oriented electrical steel sheet of this disclosure further contains at least one of Sn and Sb. In one embodiment, Sn: 0-0.20%, preferably 0.02-0.20%. In one embodiment, Sb: 0-0.10%, preferably 0.01-0.10%. In one embodiment, 0 < Sn + Sb ≤ 0.25%, preferably 0.03 ≤ Sn + Sb ≤ 0.25%.

Preferably, the unavoidable impurities in the non-oriented electrical steel sheet of this disclosure include S, N and Ti, and S≤0.0030%, N≤0.0030% and Ti≤0.0010%.

Preferably, the average grain size of the non-oriented electrical steel sheet disclosed herein is 85–130 μm.

Preferably, the thickness of the non-oriented electrical steel sheet disclosed herein is 0.35 to 0.50 mm.

Preferably, the yield strength Y _{_S} of the non-oriented electrical steel sheet disclosed herein is 280–400 MPa.

In this invention, the yield strength Y _{_S} of the finished steel sheet is closely related to its workability. On the one hand, a lower yield strength Y _{_S} is detrimental to blanking because the material is too soft and prone to burr formation, and the abnormal increase in the shear surface area leads to a decrease in the lamination factor, deteriorating the electromagnetic properties of the finished steel sheet. On the other hand, a higher yield strength Y_{_S} is also detrimental to blanking because the material is too hard and prone to damaging the die, resulting in an abnormally reduced die life, and the abnormal increase in the tensile surface area generates shear stress. Furthermore, excessively high yield strength will also deteriorate the electromagnetic properties of the finished steel sheet. Based on this, this invention limits the yield strength Y_{_S} of the non-oriented electrical steel sheet to 280–400 MPa.

Preferably, the non-oriented electrical steel sheet of this disclosure has an iron loss P _1.5/200 ≤11.2W/kg and a magnetic induction B ₃₀₀ ≥1.40T.

More preferably, the iron loss P _1.5/200 of the non-oriented electrical steel sheet disclosed herein is 10.0 to 11.2 W/kg, and the magnetic induction B ₃₀₀ is 1.40 to 1.43 T.

More preferably, the performance of the non-oriented electrical steel sheet disclosed herein meets the following requirements: within 3 million punching cycles, the iron loss deterioration rate is not greater than 1%; within 5 million punching cycles, the iron loss deterioration rate is not greater than 2%.

Another objective of this invention is to provide a method for manufacturing non-oriented electrical steel sheets with excellent punching processability. This method obtains non-oriented electrical steel sheets with good iron loss, magnetic induction and punching processability by optimizing the continuous annealing process.

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

(1) Smelting and casting;

(2) Heating and hot rolling;

(3) Cold rolling is performed after pickling;

(4) Continuous annealing: The soaking time is 5 to 60 seconds, and the soaking temperature is T = 850 + 20a[Si + Al], where the unit of the soaking temperature T is ℃, [Si + Al] represents the value before the percentage sign of the total mass percentage of Si and Al, and a represents the texture factor coefficient, where a = 1.2 to 3.6.

In this invention, the homogenization temperature of continuous annealing is related to the total content of Si and Al in the chemical composition and the texture factor coefficient a. The texture factor coefficient a is the ratio of crystal texture (111)/[(100)+(110)+(111)], which can be obtained by detecting the crystal textures (100), (110), and (111) in the finished steel plate using X-RD (X-ray diffraction). When the total content of Si and Al is high, a higher homogenization temperature is required to reduce the iron loss of the finished steel plate; when the texture factor coefficient is large, the unfavorable texture (111) is easily generated. Therefore, the homogenization temperature needs to be controlled to ensure that the favorable textures (100) and (110) grow rapidly in the high-temperature stage after the Curie temperature, thereby improving the punching processability of the material.

Preferably, in the manufacturing method disclosed herein, a normalization step is further included between steps (2) and (3), with a normalization temperature of 850 to 1050°C and an atmosphere of hydrogen with a volume fraction of 0 to 40% plus the balance of nitrogen.

Preferably, in step (2) of the manufacturing method disclosed herein, the furnace exit temperature of the billet is 1050-1200°C, the final rolling temperature is 800-1000°C, and the coiling temperature is 500-750°C.

Preferably, in step (2) of the manufacturing method disclosed herein, the thickness of the hot-rolled plate is 1.2 to 2.8 mm.

Preferably, in step (1) of the manufacturing method disclosed herein, calcium treatment is performed during smelting to improve the control of inclusions.

In the manufacturing method disclosed herein, an insulating coating may be applied as needed after continuous annealing.

The non-oriented electrical steel sheet disclosed herein has the following advantages and beneficial effects:

The non-oriented electrical steel sheet disclosed herein not only has low iron loss, but also high magnetic induction and excellent punching processability.

In some embodiments, the yield strength Y _{_S} of the non-oriented electrical steel sheet of this disclosure is 280-400 MPa, the iron loss P _{_1.5/200} ≤11.2 W/kg, and the magnetic induction B _₃₀₀ ≥1.40 T.

In some embodiments, the performance of the non-oriented electrical steel sheet disclosed herein meets the following requirements: within 3 million punching cycles, the iron loss deterioration rate is not greater than 1%; within 5 million punching cycles, the iron loss deterioration rate is not greater than 2%.

The manufacturing method of the non-oriented electrical steel sheet disclosed herein is simple, easy to control, low in cost, high in precision, and easy to implement.

Attached Figure Description

Figure 1 shows the relationship between the yield strength Y _{_S} and the punching processability of non-oriented electrical steel sheets.

Figure 2 shows the difference in iron loss P _1.5/200 degradation effect during the punching process between the non-oriented electrical steel sheet of Example 1 and the control steel sheet of Comparative Example 1.

Figure 3 shows a schematic diagram of the shearing surface and tensile fracture surface of the non-oriented electrical steel sheet of Example 3 during the shearing and punching process.

Detailed Implementation

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

In this paper, the average grain size was determined according to the Chinese national standard GB T 6394-2017, using the method for determining the average grain size of metals.

In this paper, iron loss P _1.5/200 refers to the iron loss at a magnetic flux density of 1.5T and a magnetization frequency of 200Hz. Iron loss P _1.5/200 is measured according to the Chinese national standard GB/T 3658-1990 using the Epstein square method.

In this paper, magnetic induction B ₃₀₀ refers to the magnetic induction intensity measured under an applied magnetic field strength of 300 A/m. Magnetic induction B ₃₀₀ was measured using the Epstein square method according to the Chinese national standard GB/T 3658-1990.

In this paper, the yield strength Y_{_S} was determined according to the Chinese national standard GB/T 228.1-2010.

In this paper, the texture factor coefficient is the ratio of crystal texture (111)/[(100)+(110)+(111)], which is obtained by detecting the crystal texture of (100), (110), and (111) in the finished steel plate using X-RD (X-ray diffractometer).

The design principles of each chemical element in the non-oriented electrical steel sheet disclosed herein are as follows:

C: In the non-oriented electrical steel sheet of this disclosure, when the C element content is higher than 0.004%, magnetic aging will occur, deteriorating the electromagnetic properties of the steel. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of C element is controlled between 0 < C ≤ 0.004%, preferably 0 < C ≤ 0.0039%, and more preferably 0.0012 < C ≤ 0.0039%.

Si: In the non-oriented electrical steel sheet of this disclosure, when the Si content is below 1.6%, the iron loss of the steel cannot be effectively reduced; when the Si content is above 3.4%, it will lead to a significant reduction in machinability. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage of Si is controlled between 1.6% and 3.4%.

Mn: In the non-oriented electrical steel sheet disclosed herein, when the Mn content is below 0.05%, the austenite phase region cannot be effectively expanded; when the Mn content is above 0.5%, it leads to a significant increase in cost. Therefore, in the non-oriented electrical steel sheet disclosed herein, the mass percentage content of Mn is controlled between 0.05% and 0.50%.

P: In the non-oriented electrical steel sheet of this disclosure, when the content of P element is less than 0.02%, the proportion of favorable crystal texture cannot be effectively improved; when the content of P element is greater than 0.10%, it will lead to a decrease in cold rolling stability. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of P element is controlled between 0.02% and 0.10%.

Al: In the non-oriented electrical steel sheet of this disclosure, when the Al content is higher than 0.5%, the proportion of favorable grain texture is significantly reduced, and the magnetic induction of the steel is greatly deteriorated. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of Al is controlled between 0 < Al ≤ 0.50%.

Ca: In the non-oriented electrical steel sheet of this disclosure, when the Ca content is below 0.0003%, it is not conducive to controlling harmful inclusions in the steel; when the Ca content is above 0.004%, it will reduce the stability of continuous casting. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage of Ca is controlled between 0.0003% and 0.0040%.

Cr: In the non-oriented electrical steel sheet of this disclosure, when the Cr content is below 0.01%, it is not conducive to improving the punching performance; when the Cr content is above 0.20%, it leads to a decrease in the proportion of favorable crystal texture. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of Cr is controlled between 0.01% and 0.20%.

In addition, in order to achieve a balanced improvement in iron loss, magnetic properties and punching processability of non-oriented electrical steel sheets, the content is controlled to be 1.8% ≤ (Si+Al) ≤ 3.6%.

Preferably, the non-oriented electrical steel sheet of this disclosure further contains at least one of the following chemical elements in the following mass percentages: 0 < Ge ≤ 0.02%; 0 < Bi ≤ 0.01%; 0 < REM ≤ 0.02%.

Ge: In the non-oriented electrical steel sheet of this disclosure, Ge can significantly increase the proportion of favorable crystal texture. When the Ge content exceeds 0.02%, the manufacturing cost increases substantially. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of Ge is controlled to 0 < Ge ≤ 0.02%.

Bi: In the non-oriented electrical steel sheet of this disclosure, Bi can significantly increase the proportion of favorable crystal texture. When the Bi content is higher than 0.01%, it leads to severe grain refinement. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of Bi is controlled to be 0 < Bi ≤ 0.01%.

REM: In the non-oriented electrical steel sheet of this disclosure, REM can improve the cleanliness of the steel and promote grain growth. When the REM content is higher than 0.02%, it will lead to a significant increase in manufacturing costs. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of REM is controlled to 0 < REM ≤ 0.02%.

Preferably, the non-oriented electrical steel sheet of this disclosure further contains at least one of Sn and Sb, and Sn: 0 to 0.20%, Sb: 0 to 0.10%, 0 < Sn + Sb ≤ 0.25%.

Sn and Sb: In the non-oriented electrical steel sheet of this disclosure, Sn and Sb elements can promote favorable crystal texture growth, improve magnetic induction, and reduce iron loss. However, excessive addition of Sn and Sb elements can lead to grain refinement and abnormal segregation. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of Sn element is controlled at 0–0.20%, and the mass percentage content of Sb element is controlled at 0–0.10%. Furthermore, the sum of the mass percentage contents of Sn and Sb elements is controlled to be 0 < Sn + Sb ≤ 0.25%.

In the above technical solution, 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:

S: In the non-oriented electrical steel sheet of this disclosure, when the sulfur (S) content is higher than 0.003%, it significantly increases sulfide inclusions and inhibits grain growth. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage of sulfur is controlled to S ≤ 0.0030%.

N: In the non-oriented electrical steel sheet of this disclosure, when the N element content is higher than 0.003%, it will significantly increase nitride inclusions and inhibit grain size growth. Therefore, in the non-oriented electrical steel sheet of this disclosure, the mass percentage content of N element is controlled to N≤0.0030%.

Ti: In the non-oriented electrical steel sheet of this disclosure, when the Ti element content is higher than 0.001%, it will significantly increase nitride inclusions and inhibit grain size growth. Therefore, in the non-oriented electrical steel sheet of this disclosure, Ti element is controlled as an impurity, and its content is controlled to be Ti≤0.0010%.

In one embodiment, in the manufacturing method disclosed herein, the steelmaking raw material is blast furnace iron or high-quality scrap steel, or a combination of blast furnace iron and high-quality scrap steel in a certain proportion.

In one embodiment, the steelmaking process of this disclosure employs either converter steelmaking and continuous casting, or electric furnace steelmaking and continuous casting.

The non-oriented electrical steel sheet and its manufacturing method disclosed herein will be further explained and described below with reference to specific embodiments and accompanying drawings. However, such explanation and description do not constitute an undue limitation on the technical solution of the present invention.

Examples 1-8 and Comparative Examples 1-2

The non-oriented electrical steel sheets of Examples 1-8 and Comparative Examples 1-2 were prepared by the following steps:

(1) Smelting and casting: Steelmaking adopts converter steelmaking and continuous casting. During smelting, calcium treatment is carried out (√) or not (×).

(2) Heating and hot rolling: The furnace exit temperature of the billet is 1050～1200℃, the final rolling temperature is 800～1000℃, the coiling temperature is 500～750℃, and the thickness of the hot-rolled plate is 1.2～2.8mm; then proceed directly to step (4), or proceed to step (3) first and then to step (4).

(3) Normalizing, holding, slow cooling and bell-type furnace annealing: the normalizing temperature is 850-1050℃, and the atmosphere is hydrogen with a volume fraction of 0-40% + the balance is nitrogen;

(4) Cold rolling after pickling: After pickling, cold rolling is carried out using a cold continuous rolling mill or a reciprocating rolling mill; the target thickness of the cold-rolled non-oriented electrical steel sheet is controlled at 0.35 to 0.50 mm.

(5) Continuous annealing: control the soaking time to be 5 to 60 s, and the soaking temperature to be T = 850 + 20a[Si + Al], where the unit of soaking temperature T is ℃, [Si + Al] represents the value before the percentage sign of the total mass percentage of Si and Al, and a represents the texture factor coefficient, with a value ranging from 1.2 to 3.6.

Comparative Examples 1 and 2 employed conventional continuous annealing treatment and did not design a soaking temperature based on the soaking temperature T = 850 + 20a[Si + Al].

Tables 1-1 and 1-2 list the mass percentage of each chemical element in the non-oriented electrical steel sheets of Examples 1-8 and the comparative steels of Comparative Examples 1-2.

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

Table 1-2. (wt%, balance Fe and other unavoidable impurities besides S, N and Ti)

Table 2 lists the specific process parameters for the non-oriented electrical steel sheets of Examples 1-8 and the comparative steels of Comparative Examples 1-2.

Table 2.

Note: The texture factor coefficient a is the ratio of crystal texture (111)/[(100)+(110)+(111)], which is obtained by detecting the crystal texture of (100), (110), and (111) in the finished steel plate using X-RD (X-ray diffractometer).

Samples were taken from the non-oriented electrical steel sheets of Examples 1-8 and the control steels of Comparative Examples 1-2. The samples from each example and comparative example steel sheet were observed, and various relevant properties were tested. The results of the observations and related performance tests are listed in Table 3. The specific test methods for the relevant properties are described below:

Grain size testing: Based on the Chinese national standard GB T 6394-2017, the average grain size of metal was measured using the method for determining grain size.

Iron loss performance test: Based on the Chinese national standard GB/T 3658-1990, the iron loss performance test was conducted using the Epstein square circle method. The test temperature was 20℃ constant temperature test, the sample size was 30mm×300mm, the target mass was 0.5kg, and the test parameter was P1.5/200.

Magnetic performance testing: Based on the Chinese national standard GB/T 3658-1990, the iron loss performance was tested using the Epstein square ring method. The test temperature was a constant temperature test at 20℃, the sample size was 30mm×300mm, the target mass was 0.5kg, and the test parameter was B ₃₀₀ .

Yield strength test: Based on the Chinese national standard GB/T 228.1-2010, the yield strength test was conducted using machined standard specimens. The test temperature was constant at 20℃. The gauge length of the specimen for tensile testing was 50mm. The measurement results are displayed as the average of 3 tests.

Table 3 lists the observation results and related performance test results of the non-oriented electrical steel sheets of Examples 1-8 and the control steels of Comparative Examples 1-2.

Table 3.

As can be seen from Table 3 above, the average grain size of the non-oriented electrical steel sheets in Examples 1-8 is between 85 and 130 μm, the iron loss P _1.5/200 is between 10.0 and 11.2 W/kg, and the magnetic induction B ₃₀₀ is between 1.41 and 1.43 T, indicating excellent electromagnetic properties. Furthermore, the yield strength _YS of Examples 1-8 is between 280 and 400 MPa, demonstrating excellent punching performance.

Figure 1 shows the relationship between the yield strength Y _{_S} and the punching processability of non-oriented electrical steel sheets.

As shown in Figure 1, when the yield strength Y_{_S} is low, for example below 280 MPa, the steel is relatively soft and prone to burr formation. Furthermore, the abnormal increase in the shear surface area leads to a decrease in the lamination coefficient, deteriorating the electromagnetic properties of the finished steel plate, thus hindering punching processes. When the yield strength Y_{_S} is high, for example above 400 MPa, the steel is relatively hard and prone to damaging the die, resulting in an abnormally reduced die life. Additionally, the abnormal increase in the tensile surface area generates shear stress, similarly deteriorating the electromagnetic properties of the finished steel plate, thus hindering punching processes.

Figure 2 shows the difference in iron loss P _1.5/200 degradation effect during the punching process between the non-oriented electrical steel sheet of Example 1 and the control steel sheet of Comparative Example 1.

As the blanking process continues, the blanking area at the end of the test sample becomes larger and larger. For each blanking surface, the shear surface and tensile fracture surface will change. As shown in Figure 2, as the blanking process continues, the difference in iron loss P _1.5/200 degradation between Example 1 and Comparative Example 1 becomes more and more obvious.

The comparative steel plate of Comparative Example 1 has an average grain size of 135 μm, a yield strength Y _{_S} of 265 MPa, an iron loss P _{_1.5/200} of 11.4 W/kg, and a magnetic induction B _₃₀₀ of 1.36 T, which is significantly inferior to the embodiment of the present invention.

The comparative steel plate in Comparative Example 2 has an average grain size of 82 μm, a yield strength Y _{_S} of 420 MPa, an iron loss P _{_1.5/200} of 11.7 W/kg, and a magnetic induction B _₃₀₀ of 1.38 T, which is significantly inferior to the embodiment of the present invention.

Figure 3 shows a schematic diagram of the shearing surface and tensile fracture surface of the non-oriented electrical steel sheet in Example 3 during the shearing and punching process.

As shown in Figure 3, the proportions of shear surface and tensile fracture surface in the cross-sectional morphology of the sample are relatively balanced. The shear surface is very flat and smooth, and the boundary between it and the tensile fracture surface is obvious, indicating that the residual stress generated by the material during processing is small, and the effect on controlling the iron loss deterioration of the finished sample is very good.

All publications, patent applications, patents and other references mentioned in this disclosure are incorporated herein by reference in their entirety.

While this disclosure has been illustrated and described with reference to certain preferred embodiments, those skilled in the art should understand that the above description is a further detailed explanation of the disclosure in conjunction with specific embodiments, and should not be construed as limiting the specific implementation of this disclosure to these descriptions. Various changes in form and detail can be made by those skilled in the art, including some simple deductions or substitutions, without departing from the spirit and scope of this disclosure.

Claims (14)

A non-oriented electrical steel sheet, in addition to containing Fe and unavoidable impurities, also contains the following chemical elements in the following mass percentages:
0＜C≤0.004%, Si: 1.6～3.4%, Mn: 0.05～0.50%, P: 0.02～0.10%,
0 < Al ≤ 0.50%, Ca: 0.0003～0.0040%, Cr: 0.01～0.20%; of which Si + Al total 1.8～3.6%. The non-oriented electrical steel sheet as described in claim 1, wherein the mass percentage content of each chemical element in the non-oriented electrical steel sheet is:
0＜C≤0.004%, Si: 1.6～3.4%, Mn: 0.05～0.50%, P: 0.02～0.10%,
0 < Al ≤ 0.50%, Ca: 0.0003～0.0040%, Cr: 0.01～0.20%; the balance is Fe and unavoidable impurities; The total content of Si and Al is 1.8% to 3.6%. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the non-oriented electrical steel sheet further contains at least one of the following chemical elements in a mass percentage:
0 < Ge ≤ 0.02%;
0 < Bi ≤ 0.01%;
0 < REM ≤ 0.02%. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the non-oriented electrical steel sheet further contains at least one of Sn and Sb, and Sn: 0-0.20%, preferably 0.02-0.20%, Sb: 0-0.10%, preferably 0.01-0.10%, 0 < Sn + Sb ≤ 0.25%, preferably 0.03 ≤ Sn + Sb ≤ 0.25%. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein unavoidable impurities include S, N and Ti, and S≤0.0030%, N≤0.0030%, and Ti≤0.0010%. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the average grain size of the non-oriented electrical steel sheet is 85 to 130 μm. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the thickness of the non-oriented electrical steel sheet is 0.35 to 0.50 mm. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the yield strength Y_{_S} of the non-oriented electrical steel sheet is 280–400 MPa. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the iron loss P _1.5/200 of the non-oriented electrical steel sheet is ≤11.2W/kg and the magnetic induction B ₃₀₀ is ≥1.40T. The non-oriented electrical steel sheet as described in claim 1 or 2, wherein the performance of the non-oriented electrical steel sheet meets the following requirements: within 3 million punching cycles, the iron loss deterioration rate is not greater than 1%; within 5 million punching cycles, the iron loss deterioration rate is not greater than 2%. A method for manufacturing non-oriented electrical steel sheet according to any one of claims 1-10, comprising the following steps: (1) Smelting and casting: Calcium treatment is preferred during smelting; (2) Heating and hot rolling; (3) Cold rolling is performed after pickling; (4) Continuous annealing: The soaking time is 5 to 60 seconds, and the soaking temperature is T = 850 + 20a[Si + Al], where the unit of the soaking temperature T is ℃, [Si + Al] represents the value before the percentage sign of the total mass percentage of Si and Al, and a represents the texture factor coefficient, where a = 1.2 to 3.6. The method as described in claim 11, wherein a normalization step is further included between steps (2) and (3), the normalization temperature is 850 to 1050°C, and the atmosphere is hydrogen with a volume fraction of 0 to 40% and the balance being nitrogen. The method as described in claim 11, wherein in step (2), the furnace exit temperature of the billet is 1050-1200℃, the final rolling temperature is 800-1000℃, and the coiling temperature is 500-750℃. The method as described in claim 11, wherein in step (2), the thickness of the hot-rolled plate is 1.2 to 2.8 mm.