A high-strength non-oriented electrical steel with excellent magnetic properties and its manufacturing method

Abstract

This invention discloses a high-strength non-oriented electrical steel with excellent magnetic properties and its manufacturing method, relating to the field of metallurgical materials technology. The chemical composition of the non-oriented electrical steel, by weight percentage, is: C: 0.001-0.005%, Si: 1.1-2.0%, Mn: 0.4-0.7%, Al: 1.1-2.0%, P: 0.2-0.35%, S: ≤0.005%, Ce: 0.015-0.035%, with the balance being iron and unavoidable impurities. This invention optimizes the content of Si, Al, Mn, P, and Ce, removing harmful impurities while simultaneously enhancing strength through precipitation strengthening. Subsequent processes include smelting, continuous casting, hot rolling, normalizing, cold rolling, and annealing, ultimately yielding a high-strength non-oriented silicon steel with excellent magnetic properties.

Description

Technical Field

[0001] This invention relates to the field of metallurgical materials technology, specifically to a high-strength non-oriented electrical steel with excellent magnetic properties and its manufacturing method. Background Technology

[0002] With increasing environmental protection requirements, new energy vehicles, as environmentally friendly modes of transportation, are developing rapidly. The drive motor is one of the core components of new energy vehicles, requiring miniaturization, high efficiency, and high torque. The miniaturization and high efficiency of the motor necessitate that the non-oriented electrical steel used to manufacture its core possess low iron loss and high magnetic flux density. Increased speed generates enormous centrifugal force, which can easily damage the motor rotor; therefore, non-oriented electrical steel needs high strength to ensure safety at high speeds. Traditional non-oriented silicon steel can meet the requirements of low iron loss and high magnetic flux density, but its strength is relatively low. Strength and iron loss are contradictory indicators; increasing strength reduces magnetic properties. Therefore, developing low-iron-loss, high-strength non-oriented electrical steel for new energy vehicle drive motors is an important research task.

[0003] The main methods to improve the strength of non-oriented electrical steel include precipitation strengthening, solid solution strengthening, dislocation strengthening, and composite strengthening. Precipitation strengthening mainly improves strength by forming fine carbide particles with C through microalloying elements. These fine carbide particles hinder magnetic domain rotation and reduce magnetic properties. Solid solution strengthening improves strength through elements such as Si, Mn, Al, and Cu. However, excessive Si can lead to difficulties in cold rolling, and the addition of Cu can cause "copper embrittlement," increasing the difficulty of rolling. Furthermore, high-temperature annealing is required to temporarily dissolve Cu and delay recrystallization. Higher heating temperatures can cause abnormal grain growth, which is not conducive to improving strength.

[0004] Japan began researching high-strength non-oriented electrical steel in the 1980s. For example, Nippon Steel & Sumitomo Metal Corporation (formerly Nippon Steel and Sumitomo Metal, abbreviated as NSSMC) and JFE disclosed a high-strength non-oriented electrical steel sheet in patent 201280004130.1, which incorporates 0.5-3.0% Ni and 0.5-3.0% Cu. Through high-temperature annealing, the interaction between Cu precipitates and sulfides results in both good magnetic properties and excellent strength. 1.0 / 400 =20.2-30.5 W / kg, yield strength R el The strength is 750-820 MPa. Japanese Patent 200980113090.2 discloses a high-strength non-oriented electrical steel sheet and its manufacturing method. By adding 0.5-3.0% Cu, and then annealing the Cu at a high temperature of 950-1000℃, a strengthened steel sheet is precipitated. However, the high annealing temperature leads to abnormal grain growth in some areas, which is detrimental to iron loss (P). 1.0 / 400 The reduction and magnetic induction B 50 The increase in magnetic induction B 50For 1.60-1.65T, iron loss P 1.0 / 400 With a strength of 25.0-30.0 W / kg, the iron loss and magnetic induction do not meet the high-efficiency requirements of non-oriented electrical steel for new energy vehicles.

[0005] Domestic research and development of high-strength non-oriented electrical steel is also accelerating. For example, Chinese patent CN106282781A discloses a method for preparing high-strength non-oriented silicon steel based on nano-Cu precipitation strengthening. This method utilizes the fact that nano-Cu precipitation has little hindrance to the movement of magnetic domain walls, significantly increasing strength while barely affecting magnetic induction. However, the Cu precipitation strengthening method requires high-temperature annealing to temporarily dissolve Cu, delay recrystallization, and control the recrystallization rate. However, high-temperature annealing causes abnormal growth of some grains, affecting magnetic induction. 50 The iron loss is 1.67-1.74T, and the iron loss is P. 1.0 / 400 The iron loss is 22.5-31.5 W / kg, which is relatively high.

[0006] Chinese patents CN106435358A and CN105803311A, through the use of twin-roll thin strip continuous casting technology, the addition of precipitation strengthening element Nb, combined with composition design, rolling, and heat treatment, produce non-oriented electrical steel with excellent magnetic properties and high strength, and magnetic flux density of Nb. 50 The iron loss is 1.68-1.73T, and the iron loss is P. 1.0 / 400 The iron loss is relatively high, ranging from 25.5 to 37.5 W / kg.

[0007] Baosteel's patent CN108286014A improves strength through the solid solution strengthening ability of Si, but the high Si content reduces the toughness of the steel plate, which is not conducive to product processing. Chinese patent CN106435358A uses ultra-low C steelmaking technology and improves strength by adding the precipitation strengthening element Nb, but its finished product has low iron loss (P). 1.0 / 400 The higher value is 28.0-38.2 W / kg; Chinese patent CN111235461A uses a high C (0.03-0.08%) composition system, and improves the strength of non-oriented silicon steel by adding Nb, Ti and trace rare earth elements, but C and Ti will reduce the magnetic properties of non-oriented silicon steel.

[0008] Maanshan Iron & Steel's patent CN113981329A, while employing a Ce+Sn compound, helps improve the strength and magnetic properties of non-oriented electrical steel. However, controlling the ratio of Ce and Sn requires simultaneously considering the negative impacts of each component, inevitably affecting the individual control and improvement of the strength and magnetic properties of the non-oriented electrical steel, thus failing to achieve the desired effect. Furthermore, Sn is relatively more expensive than Ce. In addition, the Si content of 2.4-3.0% used in this patent is still relatively high, which will affect the magnetic properties and toughness of the electrical steel. Summary of the Invention

[0009] In view of the above problems, this invention proposes a high-strength non-oriented electrical steel with excellent magnetic properties and its manufacturing method, so that the electrical steel has both low iron loss and high strength. This invention optimizes the content of Si, Al, Mn, P, and Ce to remove harmful impurities while precipitation strengthening to improve strength. Subsequently, it undergoes smelting, continuous casting, hot rolling, normalizing, cold rolling, and annealing to finally obtain a high-strength non-oriented silicon steel with excellent magnetic properties.

[0010] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0011] This invention proposes a high-strength non-oriented electrical steel with excellent magnetic properties. The chemical composition of the non-oriented electrical steel, by weight percentage, is as follows: C: 0.001-0.005%, Si: 1.1-2.0%, Mn: 0.4-0.7%, Al: 1.1-2.0%, P: 0.2-0.35%, S: ≤0.005%, Ce: 0.015-0.035%, with the balance being iron and unavoidable impurities.

[0012] Preferably, the chemical composition of the non-oriented electrical steel, by weight percentage, is: C: 0.002%, Si: 1.95%, Mn: 0.69%, Al: 2.0%, P: 0.34%, S: 0.001%, Ce: 0.025%, with the balance being iron and unavoidable impurities.

[0013] Preferably, the weight ratio Mn / P is ≥ 2.

[0014] Preferably, the weight percentage content of Si is less than that of Al.

[0015] Preferably, the magnetic properties of the non-oriented electrical steel are: when the thickness is 0.30 mm, B 50 =1.68-1.75T, P 1.0 / 400 =15.5-19.5 W / kg, yield strength Rel is 550-650 MPa, tensile strength Rm is 650-750 MPa, elongation A 50 ≤20%.

[0016] This invention also provides a method for manufacturing high-strength non-oriented electrical steel with excellent magnetic properties, comprising the following steps: hot metal pretreatment → converter smelting → continuous casting → hot rolling → coiling → normalizing → cold rolling → annealing → finished product.

[0017] Preferably, the initial hot rolling temperature is 1100-1200℃ and the final hot rolling temperature is 900-950℃, which can further reduce the risk of phosphorus embrittlement.

[0018] Preferably, the curling temperature is 680-710℃.

[0019] Preferably, the normalization temperature is 900-1000℃.

[0020] Preferably, the annealing temperature is 850-950℃.

[0021] The chemical composition design of this invention, with the main alloying element content controlled as follows:

[0022] C: The main purpose of controlling the C content in this invention is to prevent C from deteriorating the magnetic properties. This invention limits the C content to 0.001-0.005%.

[0023] Si: Increasing the Si content increases the strength of the steel plate, reduces its magnetic induction, and increases its brittleness, which is detrimental to the surface quality control of hot-rolled coils. Therefore, this invention should reduce the Si content in the steel. The Si content in this invention is 1.1-2.0%.

[0024] Mn: Mn is beneficial for increasing the resistivity of electrical steel and reducing iron loss. Furthermore, its strength can be improved through solid solution strengthening. Therefore, this invention sets the Mn content to 0.4-0.7%.

[0025] Al: Increasing the Al content increases the strength and magnetic induction of the steel plate. However, excessive Al content can easily lead to stickiness in the molten steel. Therefore, this invention controls the Al content to be 1.1-2.0%. Al content can reduce iron loss without decreasing magnetic induction. Al also improves the plasticity of the steel plate and reduces the impact of phosphorus embrittlement. Furthermore, Al combines with N to form AlN, which can refine the grains and improve strength. Therefore, the weight percentage of Si and Al is set to Si% < Al.

[0026] P: P can cause segregation, refine grains, improve strength, and improve texture. However, Fe3P segregation can make the steel plate embrittled and reduce toughness. Therefore, this invention controls the content to 0.2-0.35%. If the P content is too high, the steel plate is prone to phosphorus embrittlement. Adding Mn can improve the toughness and plasticity of the steel plate and reduce the impact of phosphorus embrittlement on the steel plate. Therefore, the weight percentage content of Mn / P is ≥2.

[0027] S: S can form ductile MnS inclusions with Mn in steel, which can reduce hot brittleness, but it can also cause the strip to form a banded structure, which reduces the toughness and formability of the steel plate. In addition, S has a great influence on magnetic properties. This invention controls the S content to be ≤0.005%.

[0028] Ce: During steelmaking, Ce readily combines with impurities such as O and S in the steel to form Ce oxide sulfides, which purify the steel and improve its magnetic properties. Residual Ce precipitates after steelmaking, hindering grain growth, refining the grains, and increasing the strength of the steel plate. However, grain refinement leads to increased hysteresis loss; therefore, the weight percentage of Ce is 0.015-0.035%.

[0029] The manufacturing method for producing this high-strength non-oriented electrical steel with excellent magnetic properties requires the following steps: hot metal pretreatment → converter smelting → continuous casting → hot rolling → coiling → normalizing → cold rolling → annealing → finished product.

[0030] (1) Hot metal pretreatment: Pre-slag removal and post-slag removal measures are adopted in the hot metal pretreatment process to adjust the [S] element, which can reduce harmful elements in the molten steel. Adding self-circulating scrap steel in the early and middle stages of decarburization and modifying the ladle top slag helps to reduce impurity elements in the molten steel.

[0031] (2) Hot rolling: The initial rolling temperature is 1100-1200℃ and the final rolling temperature is 900-950℃. The hot rolling temperature should not be too high, as excessively high temperatures will cause inclusions to become finer and deteriorate the magnetic properties.

[0032] (3) Winding: The winding temperature is 680-710℃. The winding temperature helps to improve the uniformity of the product grains and improve the magnetic induction.

[0033] (3) Normalization: Normalization temperature is 900-1000℃. If the normalization temperature is too high, the grains will grow abnormally, the plasticity will decrease, and cold rolling will be difficult.

[0034] (4) Annealing: The annealing temperature is 850-950℃. This is the last process to adjust the magnetic properties. A suitable annealing temperature helps to balance the iron loss and magnetic induction.

[0035] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] The role and combined effect of the key components of this invention: (1) By optimizing and adjusting the chemical composition, this invention simplifies the original Sn+Ce compounding method to the addition of Ce alone. The addition of Ce alone retains the effect of the original Sn+Ce and eliminates the relatively high cost of Sn. When improving the strength and magnetic properties of non-oriented silicon steel, it is only necessary to overcome the negative impact of Ce dosage. The strength and magnetic properties of electrical steel can be more accurately controlled by adjusting the dosage of Ce alone. The operation is simple. (2) The microalloying effect of Ce: The addition of Ce plays a dual role. First, it purifies the steel and improves the magnetic properties. Second, it precipitates through the microalloying process, hinders grain growth, further refines the grains and improves the strength. Although grain refinement may increase hysteresis loss, this negative impact is minimized by reasonably controlling the Ce content at 0.015-0.035%. (3) Balance between Si and Al: This application further reduces the Si content to 1.1%-2.0%. Si is a key element affecting the magnetism and strength of electrical steel. A lower Si content can improve the permeability of the material to a certain extent, which is beneficial to obtaining better magnetic properties, but it also affects the mechanical strength of the material. Al can improve strength and magnetic induction, and improve strength by forming AlN with nitrogen to refine the grains, which can compensate for the deficiency of strength caused by the reduction of Si content, enhance the plasticity of the material and reduce the effect of phosphorus embrittlement. By setting Si < Al, an optimized balance of strength, magnetism and plasticity is achieved. (4) Strengthening effect of Mn: Mn not only improves the resistivity of the material and reduces iron loss, but also enhances the strength through solid solution strengthening. At the same time, the addition of Mn helps to reduce the brittleness problem caused by P. Ensuring that the weight ratio of Mn / P ≥ 2 is the key to reducing the effect of phosphorus embrittlement. (5) Fine control of P: An appropriate amount of P can refine the grains and improve the strength, but an excessive amount will lead to brittleness. By limiting the P content to 0.2-0.35% and operating in a high Mn environment, the needs of strength improvement and toughness are effectively balanced.

[0037] Synergistic effects of the process in this invention: (1) Pretreatment and converter smelting: The use of slag removal and self-circulating scrap steel in the early and late stages effectively reduces impurity elements, providing a pure raw material basis for subsequent processes, which is a prerequisite for the formation of high-quality products. (2) Temperature control in the hot rolling process: By setting the hot rolling start temperature at 1100-1200℃ and the final rolling temperature at 900-950℃, the good plasticity of the material is guaranteed, and the inclusion refinement at high temperature is avoided, thereby protecting the magnetic properties from damage. (3) Precise adjustment of coiling and normalizing temperatures: Setting the coiling temperature at 680-710℃ helps to achieve uniform grain distribution; the normalizing temperature at 900-1000℃ ensures grain stability and provides a good microstructure basis for subsequent cold rolling. These all have a direct impact on the mechanical properties and magnetic properties of the final product. (4) Careful arrangement of annealing process: The annealing temperature of 850-950℃ is the last step in adjusting the magnetic properties. By selecting this temperature range, the relationship between iron loss and magnetic induction is balanced, ensuring the high performance of the material in practical applications.

[0038] In summary, this invention achieves a dual improvement in the magnetic and mechanical properties of high-strength non-oriented electrical steel through carefully designed chemical composition and optimized manufacturing process. In particular, without relying on high-priced alloying elements (such as Sn, Cr, Cu, Ti), it demonstrates significant innovation and practicality through the effective combination of Si, Al, Mn, P, and Ce and the control of key process parameters. Detailed Implementation

[0039] To enable those skilled in the art to better understand the technical solutions of the present invention, the preferred embodiments of the present invention are described below in conjunction with specific examples. However, these should not be construed as limiting the present invention and are merely examples.

[0040] Unless otherwise specified, the test methods or experimental methods described in the following examples are conventional methods; unless otherwise specified, the reagents and materials are obtained from conventional commercial sources or prepared by conventional methods.

[0041] The present invention will be further described in detail below with reference to specific embodiments.

[0042] The inventors have utilized the optimized content of Si, Al, Mn, P, and Ce, the characteristics of Ce oxide sulfide in purifying steel and refining grains, and a reasonable composition ratio and process to improve strength and grain uniformity, reduce iron loss, promote the formation of favorable textures, and improve magnetic properties.

[0043] Through experimental research, the inventors have rationally controlled the contents of Si, Al, Mn, and P, as well as the range of Ce that is beneficial to magnetic properties.

[0044] Example 1:

[0045] The chemical composition (by weight percentage) of non-oriented electrical steel is as follows:

[0046] Table 1 Chemical composition of continuously cast billets (unit: %)

[0047] plan C Si Mn P S Al Ce 1 0.003 1.6 0.59 0.28 0.002 1.9 0.020

[0048] After smelting and continuous casting, the billet thickness is 230mm. Hot rolling begins at 1100-1200℃, ends at 920℃, and coils at 700℃, resulting in a steel plate thickness of 2.2mm. Normalizing temperature is 900-1000℃. After pickling, it is cold-rolled to 0.30mm. The cold-rolled coils are then annealed in a high-temperature tubular furnace with a protective gas of 80% nitrogen and 20% hydrogen at 850-950℃. After annealing, a semi-organic coating is applied to ensure insulation and interlayer resistance. The resulting high-strength non-oriented electrical steel has a magnetic induction intensity B. 50 It is 1.71T, W 1.0 / 400 =16.7W / Kg, yield strength R el The tensile strength is 590 MPa, and the tensile strength R is... m It is 695 MPa.

[0049] Example 2:

[0050] The chemical composition (by weight percentage) of non-oriented electrical steel is as follows:

[0051] Table 2 Chemical composition of continuously cast billets (unit: %)

[0052] plan C Si Mn P S Al Ce 1 0.002 1.95 0.69 0.34 0.001 2.0 0.025

[0053] After smelting and continuous casting, the billet thickness is 230mm. Hot rolling begins at 1100-1200℃, ends at 930℃, and coils at 710℃. The steel plate thickness is 2.2mm. Normalizing temperature is 900-1000℃. After pickling, it is cold-rolled to 0.30mm. The cold-rolled coils are then annealed in a high-temperature tubular furnace with a protective gas of 80% nitrogen and 20% hydrogen at 850-950℃. After annealing, a semi-organic coating is applied to ensure insulation and interlayer resistance. The resulting high-strength non-oriented electrical steel has a magnetic induction intensity B. 50 It is 1.68T, W 1.0 / 400 =15.5W / Kg, yield strength R el The tensile strength is 650 MPa, and the tensile strength R is... m It is 750 MPa.

[0054] Example 3:

[0055] The chemical composition (by weight percentage) of non-oriented electrical steel is as follows:

[0056] Table 3 Chemical composition of continuously cast billets (unit: %)

[0057] plan C Si Mn P S Al Ce 1 0.002 1.1 0.70 0.35 0.001 1.5 0.016

[0058] After smelting and continuous casting, the billet thickness is 230mm. Hot rolling begins at 1100-1200℃, ends at 930℃, and coils at 690℃, resulting in a steel plate thickness of 2.2mm. Normalizing temperature is 900-1000℃. After pickling, it is cold-rolled to 0.30mm. The cold-rolled coils are then annealed in a high-temperature tubular furnace with a protective gas of 80% nitrogen and 20% hydrogen at 850-950℃. After annealing, a semi-organic coating is applied to ensure insulation and interlayer resistance. The resulting high-strength non-oriented electrical steel has a magnetic induction intensity B. 50 It is 1.75T, W 1.0 / 400 =17.3W / Kg, yield strength R el The tensile strength is 580 MPa, and the tensile strength R is... m It is 685 MPa.

[0059] Example 4:

[0060] The chemical composition (by weight percentage) of non-oriented electrical steel is as follows:

[0061] Table 4 Chemical composition of continuously cast billets (unit: %)

[0062] plan C Si Mn P S Al Ce 1 0.002 1.15 0.42 0.20 0.001 1.2 0.019

[0063] After smelting and continuous casting, the billet thickness is 230mm. Hot rolling begins at 1100-1200℃, ends at 900℃, and coils at 680℃, resulting in a steel plate thickness of 2.2mm. Normalizing temperature is 900-1000℃. After pickling, it is cold-rolled to 0.30mm. The cold-rolled coils are then annealed in a high-temperature tubular furnace with a protective gas of 80% nitrogen and 20% hydrogen at 850-950℃. After annealing, a semi-organic coating is applied to ensure insulation and interlayer resistance. The resulting high-strength non-oriented electrical steel has a magnetic induction intensity B. 50 It is 1.73T, W 1.0 / 400 =16.5W / Kg, yield strength R el The tensile strength is 550 MPa, and the tensile strength R is... m It is 650 MPa.

[0064] Comparative Example 1:

[0065] The chemical composition (by weight percentage) of non-oriented electrical steel is as follows:

[0066] Table 5 Chemical composition of continuously cast billets (unit: %)

[0067] plan C Si Mn P S Al Ce 1 0.002 1.0 0.38 0.18 0.001 0.85 0.012

[0068] After smelting and continuous casting, the billet thickness is 230mm. Hot rolling begins at 1100-1200℃, ends at 940℃, and coils at 710℃, resulting in a steel plate thickness of 2.2mm. Normalizing temperature is 900-1000℃. After pickling, it is cold-rolled to 0.30mm. The cold-rolled coils are then annealed in a high-temperature tubular furnace with a protective gas of 80% nitrogen and 20% hydrogen at 850-950℃. After annealing, a semi-organic coating is applied to ensure insulation and interlayer resistance. The resulting non-oriented electrical steel has a magnetic induction intensity B. 50 It has a capacity of 1.70T and a W. 1.0 / 400 =20.9W / Kg, yield strength R el The tensile strength is 420 MPa, and the tensile strength R is... m It is 543 MPa.

[0069] Comparative Example 2:

[0070] Table 6 Chemical composition of continuously cast billets (unit: %)

[0071] plan C Si Mn P S Al Ce 1 0.002 2.2 0.78 0.40 0.001 2.1 0.040

[0072] After smelting and continuous casting, the billet thickness is 230mm. Hot rolling begins at 1100-1200℃, ends at 905℃, and coils at 690℃, resulting in a steel plate thickness of 2.2mm. Normalizing temperature is 900-1000℃. After pickling, it is cold-rolled to 0.30mm. The cold-rolled coils are then annealed in a high-temperature tubular furnace with a protective gas of 80% nitrogen and 20% hydrogen at 850-950℃. After annealing, a semi-organic coating is applied to ensure insulation and interlayer resistance. The resulting non-oriented electrical steel has a magnetic induction intensity B. 50 It is 1.66T, W 1.0 / 400 =15.6W / Kg, yield strength R el The tensile strength is 560 MPa, and the tensile strength R is... m At a pressure of 675 MPa, the plasticity of the steel plate decreases, making rolling difficult.

[0073] In summary, the high-strength non-oriented electrical steels prepared in Examples 1-4 all meet the design requirements. In Comparative Example 1, the contents of Si, Mn, P, Al, and Ce are relatively low, and the percentage content is set to Si > Al. Although the magnetic induction intensity meets the design requirements, the iron loss is high and the strength is low. In Comparative Example 2, the contents of Si, Mn, P, Al, and Ce are relatively high, and the percentage content is set to Si > Al. Although the iron loss and strength meet the design requirements, the magnetic induction is low, and the reduced plasticity makes rolling difficult.

[0074] The above are merely preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be considered as limitations on the present invention, and the scope of protection of the present invention should be determined by the scope defined in the claims. For those skilled in the art, several improvements and modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A high-strength non-oriented electrical steel with excellent magnetic properties, characterized in that, The chemical composition of the non-oriented electrical steel, by weight percentage, is: C: 0.002%, Si: 1.95%, Mn: 0.69%, Al: 2.0%, P: 0.34%, S: 0.001%, Ce: 0.025%, with the balance being iron and unavoidable impurities; the magnetic properties of the non-oriented electrical steel are: when the thickness is 0.30 mm, B... 50 =1.68-1.75T, P 1.0 / 400 =15.5-19.5W / Kg, yield strength R el The tensile strength is 550-650 MPa, and the tensile strength R is... m The strength is 650-750 MPa, and the elongation is A. 50 ≤20%.

2. The high-strength non-oriented electrical steel with excellent magnetic properties according to claim 1, characterized in that, The weight ratio Mn / P ≥ 2.

3. The high-strength non-oriented electrical steel with excellent magnetic properties according to claim 1, characterized in that, The weight percentage content of Si is less than that of Al.

4. A method for manufacturing a high-strength non-oriented electrical steel with excellent magnetic properties as described in any one of claims 1 to 3, characterized in that, The process includes the following steps: molten iron pretreatment → converter smelting → continuous casting → hot rolling → coiling → normalizing → cold rolling → annealing → finished product.

5. The method for manufacturing high-strength non-oriented electrical steel with excellent magnetic properties according to claim 4, characterized in that, The initial hot rolling temperature is 1100-1200℃, and the final hot rolling temperature is 900-950℃.

6. The method for manufacturing high-strength non-oriented electrical steel with excellent magnetic properties according to claim 4, characterized in that, The curling temperature is 680-710℃.

7. The method for manufacturing high-strength non-oriented electrical steel with excellent magnetic properties according to claim 4, characterized in that, Normalization temperature: 900-1000℃.

8. The method for manufacturing high-strength non-oriented electrical steel with excellent magnetic properties according to claim 4, characterized in that, The annealing temperature is 850-950℃.