Preparation method of rare earth non-oriented silicon steel 50W600

Abstract

The invention discloses a preparation method of rare earth non-oriented silicon steel 50W600. The preparation method comprises the steps that a converter is adopted for smelting, RH is adopted for vacuum treatment, and 30-50 kg of 20% rare earth Ce-Fe alloy is added after vacuum treatment is finished; the non-oriented silicon steel 50W600 comprises the following chemical components in percentage by mass: less than or equal to 0.0030% of C, 1.25-1.45% of Si, 0.75-0.95% of Mn, less than or equal to 0.070% of P, less than or equal to 0.003% of S, 0.30-0.50% of Als, less than or equal to 0.0020% of Ti, less than or equal to 0.0020% of N, 0.0010-0.0040% of Ce and the balance of Fe and inevitable impurities, and the total mass fraction is 100%. According to the preparation method of the rare earth non-oriented silicon steel 50W600, the magnetic performance of the non-oriented silicon steel can be effectively improved, and the iron loss is particularly obviously reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of metallurgical materials, and in particular relates to a preparation method of rare earth non-oriented silicon steel 50W600, which is mainly used for producing rare earth low iron loss non-oriented silicon steel and manufacturing iron cores of various motors and generators. Background Art

[0002] At present, application number 202210093017.0 has announced a high magnetic induction and high strength cerium-containing copper-containing non-oriented silicon steel and a manufacturing method. The focus is on alloying copper, cerium, etc. and coordinating processes to ensure magnetic properties while improving strength. The present invention focuses on the short-process process design, using rare earth elements to purify molten steel, improve inclusions, increase favorable texture components, etc., to improve the magnetic properties of 50W600.

[0003] Application No. 202310577706.3 discloses a smelting method for improving the continuous casting and pouring properties of high-grade rare earth non-oriented silicon steel. The casting technology of rare earth non-oriented silicon steel is introduced in detail to ensure the continuous casting and pouring properties. In addition to introducing smelting, the present invention focuses on the entire process of rare earth non-oriented silicon steel production, thereby obtaining non-oriented silicon steel with excellent magnetic properties.

[0004] Application No. 202410454910.0 discloses non-oriented silicon steel and its production method. The production process of rare earth non-oriented silicon steel is introduced in detail. The present invention focuses on production according to the short process - continuous casting and rolling process, improving the magnetic properties of the product, reducing production costs, and improving production efficiency. Summary of the invention

[0005] For energy conservation and environmental protection, industrial motors continuously improve their energy efficiency levels. To meet the use requirements of high-efficiency motors, the core material of motors, non-oriented silicon steel, needs to be continuously upgraded to improve performance, reduce iron loss, reduce power loss, and carbon emissions. The purpose of the present invention is to provide a method for preparing rare earth non-oriented silicon steel 50W600, which can effectively improve the magnetic properties of non-oriented silicon steel, especially significantly reducing iron loss.

[0006] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0007] The present invention provides a method for preparing rare earth non-oriented silicon steel 50W600, comprising:

[0008] The converter is used for smelting, and the RH is subjected to vacuum treatment. After the vacuum treatment, 30-50kg of rare earth Ce-Fe alloy with a taste of 20% is added;

[0009] CSP continuous casting is used to cast into 57mm thick slabs, hot rolling start temperature is 1020-1060℃, final rolling temperature is 860-890℃, coiling temperature is 735-750℃, rolled into 2.5mm thick steel strips, pickled and cold rolled into 0.5mm cold hard coils, annealing stage, heating section quickly heats up to 840±10℃, heats for 35-45s in the insulation section, so that the product performance reaches the low iron loss index, and finally insulation coating is applied to increase interlayer resistance and improve lamination coefficient;

[0010] The chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: ≤0.0030%, Si: 1.25-1.45%, Mn: 0.75-0.95%, P: ≤0.070%, S: ≤0.003%, Als: 0.30-0.50%, Ti≤0.0020%, N≤0.0020%, Ce: 0.0010-0.0040%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0011] Furthermore, the chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: 0.0025%, Si: 1.36%, Mn: 0.85%, P: 0.065%, S: 0.002%, Ti: 0.0018%, Als: 0.44%, Ce: 0.0013%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0012] Furthermore, the chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: 0.0023%, Si: 1.41%, Mn: 0.86%, P: 0.058%, S: 0.002%, Ti: 0.0016%, Als: 0.46%, Ce: 0.0022%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0013] Furthermore, the chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: 0.0022%, Si: 1.39%, Mn: 0.91%, P: 0.066%, S: 0.002%, Ti: 0.0014%, Als: 0.38%, Ce: 0.0035%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0014] Further, it specifically includes:

[0015] (1) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤ 0.003%;

[0016] (2) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1148°C;

[0017] (3) RH refining: RH is vacuum treated, and after the treatment, 30 kg of Ce-Fe alloy with a grade of 20% is added;

[0018] (4) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 28°C, furnace temperature of 958°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot; hot rolling start temperature is 1042°C, final rolling temperature is 868°C, and coiling temperature is 742°C;

[0019] (5) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 70°C, and the roughness of the steel strip is 0.4 μm;

[0020] (6) Annealing process: annealing plate temperature 842℃, holding time 40s.

[0021] Further, it specifically includes:

[0022] (1) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤ 0.003%;

[0023] (2) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1138°C;

[0024] (3) RH refining: RH is vacuum treated, and after the treatment, 38 kg of Ce-Fe alloy with a grade of 20% is added;

[0025] (4) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 26°C, furnace temperature of 962°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot; hot rolling start temperature is 1039°C, final rolling temperature is 855°C, and coiling temperature is 739°C;

[0026] (5) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 68°C, and the roughness of the steel strip is 0.38 μm;

[0027] (6) Annealing process: annealing plate temperature 839 °C, holding time 42 s.

[0028] Further, it specifically includes:

[0029] (1) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤ 0.003%;

[0030] (2) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1142°C;

[0031] (3) RH refining: RH is vacuum treated, and after the treatment, 45 kg of Ce-Fe alloy with a grade of 20% is added;

[0032] (4) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 32°C, furnace temperature of 963°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot; hot rolling start temperature is 1044°C, final rolling temperature is 871°C, and coiling temperature is 748°C;

[0033] (5) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 69°C, and the roughness of the steel strip is 0.35 μm;

[0034] (6) Annealing process: annealing plate temperature 841 °C, holding time 42 s.

[0035] Compared with the prior art, the beneficial technical effects of the present invention are:

[0036] The beneficial effects of the present invention are to improve the magnetic properties of non-oriented silicon steel, reduce iron loss, appropriately increase magnetic induction, and thus reduce motor energy consumption, thereby achieving the effect of energy saving and consumption reduction through the effect of rare earth elements and combining the process. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The present invention will be further described below in conjunction with the accompanying drawings.

[0038] Figure 1 : Example 1 organization;

[0039] Figure 2 : Example 2 organization;

[0040] Figure 3 : Example 3 organization;

[0041] Figure 4 : Comparative proportion organization. DETAILED DESCRIPTION

[0042] The present invention will be further described in detail below in conjunction with specific embodiments.

[0043] Embodiment 1:

[0044] (1) The embodiment includes the following chemical compositions in weight percentage: C: 0.0025%, Si: 1.36%, Mn: 0.85%, P: 0.065%, S: 0.002%, Ti: 0.0018%, Als: 0.44%, Ce: 0.0013%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0045] (2) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤0.003%.

[0046] (3) Converter steelmaking: The converter uses low-sulfur scrap steel and the steel tapping temperature is 1148°C.

[0047] (4) RH refining: RH is subjected to vacuum treatment, and after the treatment, 30 kg of Ce-Fe alloy with a grade of 20% is added.

[0048] (5) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 28°C, furnace temperature of 958°C, and pulling speed of 4.0m / min to ensure the quality of the ingot. The hot rolling start temperature is 1042°C, the final rolling temperature is 868°C, and the coiling temperature is 742°C.

[0049] (6) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is cleaned, the pickling speed is 200 m / min, the pickling temperature is 70°C, and the roughness of the steel strip is 0.4 μm.

[0050] (7) Annealing process: annealing plate temperature 842℃, holding time 40s.

[0051] Embodiment 2:

[0052] (1) The embodiment includes the following chemical compositions in weight percentage: C: 0.0023%, Si: 1.41%, Mn: 0.86%, P: 0.058%, S: 0.002%, Ti: 0.0016%, Als: 0.46%, Ce: 0.0022%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0053] (2) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤0.003%.

[0054] (3) Converter steelmaking: The converter uses low-sulfur scrap steel and the steel tapping temperature is 1138°C.

[0055] (4) RH refining: RH is subjected to vacuum treatment, and after the treatment, 38 kg of Ce-Fe alloy with a grade of 20% is added.

[0056] (5) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 26°C, furnace temperature of 962°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot. The hot rolling start temperature is 1039°C, the final rolling temperature is 855°C, and the coiling temperature is 739°C.

[0057] (6) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 68°C, and the roughness of the steel strip is 0.38 μm.

[0058] (7) Annealing process: annealing plate temperature 839 °C, holding time 42 s.

[0059] Embodiment 3:

[0060] (1) The embodiment includes the following chemical components in weight percentage: C: 0.0022%, Si: 1.39%, Mn: 0.91%, P: 0.066%, S: 0.002%, Ti: 0.0014%, Als: 0.38%, Ce: 0.0035%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0061] (2) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤0.003%.

[0062] (3) Converter steelmaking: The converter uses low-sulfur scrap steel and the steel tapping temperature is 1142°C.

[0063] (4) RH refining: RH is subjected to vacuum treatment, and after the treatment, 45 kg of Ce-Fe alloy with a grade of 20% is added.

[0064] (5) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 32°C, furnace temperature of 963°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot. The hot rolling start temperature is 1044°C, the final rolling temperature is 871°C, and the coiling temperature is 748°C.

[0065] (6) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 69°C, and the roughness of the steel strip is 0.35 μm.

[0066] (7) Annealing process: annealing plate temperature 841 °C, holding time 42 s.

[0067] Comparative Example:

[0068] (1) The embodiment includes the following chemical compositions in weight percentage: C: 0.0024%, Si: 1.44%, Mn: 0.83%, P: 0.065%, S: 0.002%, Ti: 0.0013%, Als: 0.41%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

[0069] (2) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤0.003%.

[0070] (3) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1145°C.

[0071] (4) RH refining: RH is subjected to vacuum treatment.

[0072] (5) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 23°C, furnace temperature of 965°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot. The hot rolling start temperature is 1036°C, the final rolling temperature is 867°C, and the coiling temperature is 741°C.

[0073] (6) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is cleaned, the pickling speed is 200 m / min, the pickling temperature is 71°C, and the roughness of the steel strip is 0.36 μm.

[0074] (7) Annealing process: annealing plate temperature 840℃, holding time 39s.

[0075] The magnetic properties of Examples 1 to 3 and the comparative example are shown in Table 1.

[0076] Table 1 Magnetic properties of steel strip

[0077] Example <![CDATA[Iron loss P 1.5 / 50 W / kg]]> <![CDATA[Magnetic induction J 5000 T]]> Tensile strength MPa Require ≤4.0 ≥1.68 ≥340 1 3.73 1.716 435 2 3.58 1.722 428 3 3.33 1.733 421 Comparative Example 3.81 1.711 437

[0078] The embodiments described above are only descriptions of the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A method for preparing rare earth non-oriented silicon steel 50W600, characterized in that: include: The converter is used for smelting, and the RH is subjected to vacuum treatment. After the vacuum treatment, 30-50kg of rare earth Ce-Fe alloy with a taste of 20% is added; CSP continuous casting is used to cast into 57mm thick slabs, hot rolling start temperature is 1020-1060℃, final rolling temperature is 860-890℃, coiling temperature is 735-750℃, rolled into 2.5mm thick steel strips, pickled and cold rolled into 0.5mm cold hard coils, annealing stage, heating section quickly heats up to 840±10℃, heats for 35-45s in the insulation section, so that the product performance reaches the low iron loss index, and finally insulation coating is applied to increase interlayer resistance and improve lamination coefficient; The chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: ≤0.0030%, Si: 1.25-1.45%, Mn: 0.75-0.95%, P: ≤0.070%, S: ≤0.003%, Als: 0.30-0.50%, Ti≤0.0020%, N≤0.0020%, Ce: 0.0010-0.0040%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

2. The method for preparing rare earth non-oriented silicon steel 50W600 according to claim 1, characterized in that: The chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: 0.0025%, Si: 1.36%, Mn: 0.85%, P: 0.065%, S: 0.002%, Ti: 0.0018%, Als: 0.44%, Ce: 0.0013%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

3. The method for preparing rare earth non-oriented silicon steel 50W600 according to claim 1, characterized in that: The chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: 0.0023%, Si: 1.41%, Mn: 0.86%, P: 0.058%, S: 0.002%, Ti: 0.0016%, Als: 0.46%, Ce: 0.0022%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

4. The method for preparing rare earth non-oriented silicon steel 50W600 according to claim 1, characterized in that: The chemical composition of the non-oriented silicon steel 50W600 in mass percentage is: C: 0.0022%, Si: 1.39%, Mn: 0.91%, P: 0.066%, S: 0.002%, Ti: 0.0014%, Als: 0.38%, Ce: 0.0035%, and the rest is Fe and unavoidable inclusions, with a total mass fraction of 100%.

5. The method for preparing rare earth non-oriented silicon steel 50W600 according to claim 2, characterized in that: Specifically include: (1) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤ 0.003%; (2) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1148°C; (3) RH refining: RH is vacuum treated, and after the treatment, 30 kg of Ce-Fe alloy with a grade of 20% is added; (4) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 28°C, furnace temperature of 958°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot; hot rolling start temperature is 1042°C, final rolling temperature is 868°C, and coiling temperature is 742°C; (5) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 70°C, and the roughness of the steel strip is 0.4 μm; (6) Annealing process: annealing plate temperature 842℃, holding time 40s.

6. The method for preparing rare earth non-oriented silicon steel 50W600 according to claim 3, characterized in that: Specifically include: (1) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤ 0.003%; (2) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1138°C; (3) RH refining: RH is vacuum treated, and after the treatment, 38 kg of Ce-Fe alloy with a grade of 20% is added; (4) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 26°C, furnace temperature of 962°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot; hot rolling start temperature is 1039°C, final rolling temperature is 855°C, and coiling temperature is 739°C; (5) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 68°C, and the roughness of the steel strip is 0.38 μm; (6) Annealing process: annealing plate temperature 839 °C, holding time 42 s.

7. The method for preparing rare earth non-oriented silicon steel 50W600 according to claim 4, characterized in that: Specifically include: (1) Hot metal pretreatment: After hot metal desulfurization pretreatment, the S content is ≤ 0.003%; (2) Converter steelmaking: The converter uses low-sulfur scrap steel and the tapping temperature is 1142°C; (3) RH refining: RH is vacuum treated, and after the treatment, 45 kg of Ce-Fe alloy with a grade of 20% is added; (4) Continuous casting and rolling: Silicon steel special protective slag and carbon-free tundish covering agent are used, with superheat of 32°C, furnace temperature of 963°C, and pulling speed of 4.0 m / min to ensure the quality of the ingot; hot rolling start temperature is 1044°C, final rolling temperature is 871°C, and coiling temperature is 748°C; (5) Cold rolling process: The elongation of the straightening machine is 1.0%. To ensure that the iron oxide scale on the surface of the steel strip is clean, the pickling speed is 200 m / min, the pickling temperature is 69°C, and the roughness of the steel strip is 0.35 μm; (6) Annealing process: annealing plate temperature 841 °C, holding time 42 s.

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