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CN-122012884-A - High-grade non-oriented silicon steel and production method of non-normalized short flow thereof

CN122012884ACN 122012884 ACN122012884 ACN 122012884ACN-122012884-A

Abstract

The application discloses a high-grade non-oriented silicon steel and a production method of a normalized-free short process thereof. The production method comprises the steps of heating a continuous casting blank, hot rolling and coiling to obtain a hot rolled plate with the thickness of 2.3-2.7 mm, carrying out pickling and cold rolling under the condition of no normalization to obtain a primary cold rolled plate with the thickness of 0.40-0.60 mm, carrying out intermediate annealing on the primary cold rolled plate to obtain an intermediate annealed plate, wherein the annealing temperature is (1195-8300 [ Si ] -2700[ Al ] +/-10) ° C, the heat preservation time is 300d+105+/-10 s, wherein [ Si ] and [ Al ] are respectively the mass percentages of Si and Al in the continuous casting blank, d is the target thickness of a finished product and the unit mm, carrying out secondary cold rolling to obtain a secondary cold rolled plate with the thickness of 0.15-0.30 mm, carrying out finished product annealing at the annealing temperature of 980-1000 ℃, and cooling, coating and finishing to obtain a non-oriented silicon steel finished product.

Inventors

  • CHEN GANG
  • Zhu henan
  • ZHOU HONGBAO
  • YUE ZHONGXIANG
  • WU SHENGJIE

Assignees

  • 江苏省沙钢钢铁研究院有限公司
  • 张家港扬子江冷轧板有限公司
  • 江苏沙钢钢铁有限公司

Dates

Publication Date
20260512
Application Date
20260320

Claims (10)

  1. 1. A method of producing unoriented silicon steel, the method comprising: heating, hot rolling and coiling the continuous casting billet in sequence to obtain a hot rolled plate with the thickness of 2.3-2.7 mm; pickling and cold rolling the hot-rolled plate under the condition of not normalizing to obtain a primary cold-rolled plate with the thickness of 0.40-0.60 mm; intermediate annealing is carried out on the primary cold-rolled sheet to obtain an intermediate annealed sheet, wherein the annealing temperature is (T+/-10) DEGC, the heat preservation time is t+/-10 s, T=1195-8300 [ Si ] -2700[ Al ], t=300d+105, wherein [ Si ] and [ Al ] are respectively the mass percentages of Si and Al in the continuous casting blank, and d is the target thickness of a finished product of non-oriented silicon steel and unit mm; Performing secondary cold rolling on the intermediate annealing plate to obtain a secondary cold-rolled plate with the thickness of 0.15-0.30 mm; Carrying out finished product annealing on the secondary cold-rolled plate to obtain a finished product annealed plate, wherein the annealing temperature is 980-1000 ℃; And cooling, coating and finishing the finished annealing plate to obtain a non-oriented silicon steel finished product.
  2. 2. The method for producing non-oriented silicon steel according to claim 1, wherein the heat-preserving period is not less than t-20s when the finished product is annealed.
  3. 3. The method for producing non-oriented silicon steel according to claim 1, wherein an acid continuous rolling process is employed in pickling and cold rolling of the hot rolled sheet.
  4. 4. The method for producing non-oriented silicon steel according to claim 1, wherein twenty-roller single-stand cold rolling mills are adopted in the secondary cold rolling, and the number of passes is 2-3.
  5. 5. The method for producing non-oriented silicon steel according to claim 1, wherein the hot rolled sheet is not preheated before cold rolling when pickling and cold rolling, and the intermediate annealed sheet is not preheated when cold rolling for the second time.
  6. 6. The method for producing non-oriented silicon steel according to claim 1, wherein when the continuous casting slab is heated, hot rolled and coiled in this order, the soaking temperature is 1100.+ -. 20 ℃, the finishing temperature of hot rolling is 860.+ -. 20 ℃ and the coiling temperature is 630.+ -. 20 ℃.
  7. 7. The method for producing non-oriented silicon steel according to claim 1, wherein the chemical components of the continuous casting blank comprise, by mass, less than or equal to 0.003% of C, 2.8-3.5% of Si, 0.2-1.0% of Mn, less than or equal to 0.050% of P, less than or equal to 0.010% of N, 0.3-1.5% of Al, less than or equal to 0.0050% of S, 0.001-0.085% of Sb+Sn, and the balance of Fe and unavoidable impurities.
  8. 8. The method for producing non-oriented silicon steel according to claim 7, wherein the chemical components of the continuous casting blank comprise, by mass, less than or equal to 0.003% of C, 2.8-3.5% of Si, 0.2-1.0% of Mn, less than or equal to 0.020% of P, less than or equal to 0.0020% of N, 0.85-1.5% of Al, less than or equal to 0.0010% of S, 0.001-0.085% of Sb+Sn, and the balance of Fe and unavoidable impurities.
  9. 9. A method of producing unoriented silicon steel, the method comprising: heating, hot rolling and coiling the continuous casting billet in sequence to obtain a hot rolled plate with the thickness of 2.3-2.7 mm; pickling and cold rolling the hot-rolled plate under the condition of not normalizing to obtain a primary cold-rolled plate with the thickness of 0.40-0.60 mm; Performing intermediate annealing on the primary cold-rolled plate to obtain an intermediate annealed plate, wherein the grain size of the intermediate annealed plate is controlled to be 40-70 mu m; Performing secondary cold rolling on the intermediate annealing plate to obtain a secondary cold-rolled plate with the thickness of 0.15-0.30 mm; Carrying out finished product annealing on the secondary cold-rolled plate to obtain a finished product annealed plate, wherein the annealing temperature is 980-1000 ℃; And cooling, coating and finishing the finished annealing plate to obtain a non-oriented silicon steel finished product.
  10. 10. The non-oriented silicon steel is characterized by comprising, by mass, less than or equal to 0.003% of C, 2.8-3.5% of Si, 0.2-1.0% of Mn, less than or equal to 0.050% of P, less than or equal to 0.010% of N, 0.3-1.5% of Al, less than or equal to 0.0050% of S, 0.001-0.085% of Sb+Sn, and the balance of Fe and unavoidable impurities; The thickness of the non-oriented silicon steel is 0.15-0.30 mm, the iron loss P 1.0/400 is less than or equal to 15.0W/kg, and the magnetic induction intensity B 5000 is more than or equal to 1.60T.

Description

High-grade non-oriented silicon steel and production method of non-normalized short flow thereof Technical Field The application belongs to the technical field of steel material preparation, and relates to a high-grade non-oriented silicon steel and a production method of a non-normalized short process. Background With the continuous development of a driving motor of a new energy automobile and a power system of a low-altitude aircraft to a high-speed and high-efficiency direction, more stringent requirements are put forward on the performance of a driving motor core material, namely high-grade non-oriented silicon steel. In the future, the market demand of high-grade non-oriented silicon steel for new energy driving motors must come to be increased in an explosive manner. At present, the conventional process flow of the high-grade non-oriented silicon steel comprises hot rolling, normalizing, pickling, single-frame cold rolling, finished product annealing and coating. However, the conventional process faces serious challenges in actual production, and the conventional process can lead to remarkable growth of crystal grains of the hot rolled plate, so that in the subsequent single-frame cold rolling process, the edges of the strip steel are extremely easy to generate microcracks due to uneven stress or poor plasticity, and the microcracks are rapidly expanded into strip breakage accidents, thereby severely restricting the production efficiency and yield and increasing the production cost. In order to solve the problem that the thin high-grade non-oriented silicon steel is easy to break in the cold rolling process, various technical schemes have been proposed in the industry. However, the technical schemes cannot fundamentally solve the problem of high probability of rolling breakage caused by normalization, and influence the continuity and efficiency of production, or can change specific performance by sacrificing the simplicity and operability of the process flow, and the production process is extremely complex, difficult to control and long in flow. Therefore, a new method is developed, the adaptability to the thickness and the plate shape of the hot rolled raw material is stronger, the process flow is simpler, the stable production can be realized, and the product can meet the requirements of magnetic property and mechanical property, so that the method becomes a technical problem to be solved in the field. Disclosure of Invention In order to solve the technical problems, the application aims to provide high-grade non-oriented silicon steel and a production method of the non-oriented silicon steel without a standardized short process. In order to achieve the above-mentioned purpose, an embodiment of the present application provides a method for producing unoriented silicon steel. The production method comprises the following steps: heating, hot rolling and coiling the continuous casting billet in sequence to obtain a hot rolled plate with the thickness of 2.3-2.7 mm; pickling and cold rolling the hot-rolled plate under the condition of not normalizing to obtain a primary cold-rolled plate with the thickness of 0.40-0.60 mm; intermediate annealing is carried out on the primary cold-rolled sheet to obtain an intermediate annealed sheet, wherein the annealing temperature is (T+/-10) DEGC, the heat preservation time is t+/-10 s, T=1195-8300 [ Si ] -2700[ Al ], t=300d+105, wherein [ Si ] and [ Al ] are respectively the mass percentages of Si and Al in the continuous casting blank, and d is the target thickness of a finished product of non-oriented silicon steel and unit mm; Performing secondary cold rolling on the intermediate annealing plate to obtain a secondary cold-rolled plate with the thickness of 0.15-0.30 mm; Carrying out finished product annealing on the secondary cold-rolled plate to obtain a finished product annealed plate, wherein the annealing temperature is 980-1000 ℃; And cooling, coating and finishing the finished annealing plate to obtain a non-oriented silicon steel finished product. Preferably, the heat preservation time is not less than t-20s when the finished product is annealed. Preferably, in pickling and cold rolling the hot rolled sheet, an acid continuous rolling process is employed. Preferably, a twenty-roller single-stand cold rolling mill is adopted in the secondary cold rolling, and the times are 2-3. Preferably, no preheating is performed before cold rolling when pickling and cold rolling the hot rolled sheet, and no preheating is performed when secondary cold rolling is performed on the intermediate annealed sheet. Preferably, when the continuous casting slab is heated, hot rolled and coiled in sequence, the soaking temperature is 1100+/-20 ℃, the final rolling temperature of hot rolling is 860+/-20 ℃, and the coiling temperature is 630+/-20 ℃. Preferably, the chemical components of the continuous casting blank comprise, by mass, less than or equal to 0.003% of C, 2.8-3.5% of S