Method for improving magnetic induction of high-temperature oriented silicon steel by adopting Cu-Sb composite inhibitor

Abstract

The invention discloses a method for improving magnetic induction of high-temperature oriented silicon steel by adopting a Cu-Sb composite inhibitor, which comprises the following steps: 1) a hot rolling process: hot rolling raw materials comprise the following chemical components in percentage by weight: 0.025-0.042% of C, 2.80-3.40% of S i, 0.16-0.24% of Mn, 0.012-0.024% of Al s, 0.25-0.45% of Cu, less than or equal to 0.020% of P, less than or equal to 0.020% of S, 0.0070-0.0120% of N, 0.0300-0.0450% of Sb and the balance of Fe and impurities; 2) decarburization annealing process; and 3) a high-temperature annealing process. By optimizing the proportion of Cu and Sb, compared with high-temperature oriented silicon steel produced by an existing process, the purpose of increasing the average magnetic induction by 0.02 T is achieved on the premise that heat treatment process parameters are not changed.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature oriented silicon steel production technology, and particularly relates to a method for improving the magnetic induction of high-temperature oriented silicon steel using Cu-Sb composite inhibitors. Background Technology

[0002] Grain-oriented silicon steel is an indispensable soft magnetic material widely used in industries such as power, electronics, and military. Its performance directly affects the energy efficiency and operational stability of power equipment such as transformers and motors, and is therefore considered an important indicator of a country's steel manufacturing technology level. Among the performance indicators of grain-oriented silicon steel, iron loss and magnetic induction intensity are two core parameters; improving these two factors is key to enhancing product performance.

[0003] Application number: 201410171365.0. This patent discloses an inhibitor for reducing the heating temperature of grain-oriented silicon steel slabs and its preparation method. The inhibitor contains elements such as C, Si, Mn, and Nb in specific weight proportions (the balance being Fe). By optimizing the composition of this inhibitor, problems such as short furnace life, coarse grains, severe edge cracking, and high energy consumption caused by excessively high heating temperatures in traditional grain-oriented silicon steel slabs are solved. After application, the heating temperature of continuously cast slabs can be reduced to below 1250℃, which can improve the yield, reduce production costs, and obtain low-temperature grain-oriented silicon steel.

[0004] Application number: 202410067258.7. This patent discloses a novel inhibitor (niobium trisulfide) and a corresponding method for preparing oriented silicon steel using low-temperature slab heating. The core of this method is the use of niobium trisulfide as a key inhibitor, optimizing the component ratio and preparation process. This solves problems such as high slab heating temperature, high energy consumption, easy edge cracking, and coarse grains in traditional oriented silicon steel preparation. It enables low-temperature slab heating, improving the yield and performance of oriented silicon steel while reducing production costs, thus meeting the demand for efficient and energy-saving preparation of oriented silicon steel.

[0005] Application number: 202511203805.0. This patent discloses a copper-containing high-magnetic-induction oriented silicon steel and its production method that eliminates the need for normalization. The core of this method is to optimize the copper content ratio and combine it with improved rolling and annealing processes to eliminate the cumbersome normalization process in traditional oriented silicon steel production. This solves the problems of long processing time, high energy consumption, and high production costs associated with traditional normalization processes, while ensuring the product possesses excellent magnetic properties. It simplifies the production process, improves production efficiency, and reduces energy consumption and costs, meeting the demand for efficient and low-cost production of high-magnetic-induction oriented silicon steel. It can be applied to the field of power equipment such as transformers. Summary of the Invention

[0006] The purpose of this invention is to provide a method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor. By optimizing the ratio of Cu to Sb, and without changing the heat treatment process parameters, the average magnetic induction of high-temperature oriented silicon steel produced by existing processes is increased by 0.02T. This method provides a more economical and reliable technical route for improving the magnetic induction intensity of high-temperature oriented silicon steel.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0008] This invention discloses a method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor, comprising:

[0009] 1) Hot rolling process

[0010] The chemical composition percentages of the hot-rolled raw materials are as follows: C: 0.025–0.042%, Si: 2.80–3.40%, Mn: 0.16–0.24%, Als: 0.012–0.024%, Cu: 0.25–0.45%, P≤0.020%, S≤0.020%, N: 0.0070–0.0120%, Sb: 0.0300–0.0450%, with the remainder being Fe and impurities.

[0011] The furnace outlet temperature is <1270℃;

[0012] The time spent in the furnace in the second heating section and the soaking section should be controlled to be less than 120 min, and the total time spent in the furnace should be less than 300 min.

[0013] The finishing mill's final rolling temperature is 930-980℃;

[0014] Winding temperature 530-590℃;

[0015] 2) Decarburization annealing process

[0016] Heat spreader temperature: 800–900℃;

[0017] Furnace atmosphere: H2 + N2 mixed gas;

[0018] Control the dew point to 40–45℃;

[0019] Strip speed: 10–30 m / min;

[0020] Heat soaking time in the heat-spreading section: 3–10 min;

[0021] 3) High-temperature annealing process

[0022] High thermal insulation temperature: 1150–1250℃;

[0023] High-temperature annealing cycle: 6-8 days.

[0024] Furthermore, the H content in the gas mixture is 5–20%.

[0025] Furthermore, the chemical composition percentage of the hot-rolled raw material is as follows: C: 0.028%, Si: 2.95%, Mn: 0.21%, Als: 0.016%, Cu: 0.35%, P: 0.012%, S: 0.007%, N: 0.0092%, Sb: 0.0351%, with the remainder being Fe and impurities.

[0026] Furthermore, the chemical composition percentage of the hot-rolled raw material is as follows: C: 0.035%, Si: 3.05%, Mn: 0.21%, Als: 0.017%, Cu: 0.30%, P: 0.013%, S: 0.008%, N: 0.0089%, Sb: 0.0427%, with the remainder being Fe and impurities.

[0027] Furthermore, the chemical composition percentage of the hot-rolled raw material is as follows: C: 0.031%, Si: 3.28%, Mn: 0.20%, Als: 0.014%, Cu: 0.39%, P: 0.013%, S: 0.007%, N: 0.0102%, Sb: 0.0329%, with the remainder being Fe and impurities.

[0028] Furthermore, by employing the synergistic effect of Cu-Sb composite inhibitors, the goal of increasing magnetic induction intensity is achieved, with the average magnetic induction of high-temperature oriented silicon steel reaching over 1.88T under the same specifications.

[0029] Furthermore, iron loss P 1.7 / 50 Reduced to below 0.96w / kg.

[0030] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0031] The synergistic effect of Cu-Sb composite inhibitors: Cu-Sb composite inhibitors combine the advantages of both elements to form a synergistic enhancement effect: Cu-based inhibitors can maintain their inhibitory effect at high temperatures; Sb elements effectively optimize the secondary recrystallization texture.

[0032] 1. Significantly reduce energy consumption and production costs, and improve economic efficiency.

[0033] This invention employs a Cu-Sb composite inhibitor system, effectively reducing the slab heating temperature to a medium-low temperature range of 1250℃ to 1300℃. Compared to the traditional MnS and AlN inhibitors, which require heating temperatures above 1300℃, this significantly reduces energy consumption, lowers wear and tear on heating furnaces and other equipment, and extends equipment lifespan.

[0034] 2. Increase magnetic induction intensity

[0035] Cu and Sb elements play a synergistic role in inhibiting and optimizing texture during secondary recrystallization. Through the synergistic design of their content ratio and key hot working process parameters, a composite effect of "1+1>2" is achieved, which can increase the magnetic induction of finished grain-oriented silicon steel by an average of 0.02T, which cannot be achieved by a single inhibitor or a simple combination. Detailed Implementation

[0036] To better explain the present invention, the following is a detailed description of its implementation. Tables 1-3 show the chemical composition, hot rolling process, decarburization annealing process, high-temperature annealing process, and magnetic property statistics of Examples 1-3 and the comparative examples, respectively.

[0037] The present invention is mainly intended to compare the effects of chemical composition, hot rolling process, and synergistic effects between processes on the magnetic properties of products. Therefore, all embodiments and comparative examples use the same decarburization annealing and high-temperature annealing processes (fluctuations in process parameters within a reasonable range can be ignored).

[0038] Table 1. Chemical composition (wt%) of Examples 1-3 and Comparative Example 1

[0039]

[0040]

[0041] Table 2 Hot rolling process parameters for Examples 1-3 and comparative examples.

[0042]

[0043] Table 3. Statistical results of decarburization annealing and high-temperature annealing process parameters and magnetic properties in Examples 1-3 and the comparative examples.

[0044] As can be seen from Tables 1-3, the high-temperature copper-containing oriented silicon steel produced by the method of the present invention in the embodiments achieves the goal of increasing magnetic induction intensity by adopting the synergistic effect of Cu-Sb composite inhibitor. Under the same specifications, the average magnetic induction of the high-temperature oriented silicon steel in the embodiments can reach more than 1.88T, achieving the goal of high magnetic induction. Compared with the comparative example, the average magnetic induction can be increased by about 0.2T, and the iron loss is also better than that of the comparative example.

[0045] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor, characterized in that: include: 1) Hot rolling process The chemical composition percentages of the hot-rolled raw materials are as follows: C: 0.025–0.042%, Si: 2.80–3.40%, Mn: 0.16–0.24%, Als: 0.012–0.024%, Cu: 0.25–0.45%, P≤0.020%, S≤0.020%, N: 0.0070–0.0120%, Sb: 0.0300–0.0450%, with the remainder being Fe and impurities. The furnace outlet temperature is <1270℃; The time spent in the furnace in the second heating section and the soaking section should be controlled to be less than 120 min, and the total time spent in the furnace should be less than 300 min. The finishing mill's final rolling temperature is 930-980℃; Winding temperature 530-590℃; 2) Decarburization annealing process Heat spreader temperature: 800–900℃; Furnace atmosphere: H2 + N2 mixed gas; Control the dew point to 40–45℃; Strip speed: 10–30 m / min; Heat soaking time in the heat-spreading section: 3–10 min; 3) High-temperature annealing process High thermal insulation temperature: 1150–1250℃; High-temperature annealing cycle: 6-8 days.

2. The method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor according to claim 1, characterized in that: The H content in the mixed gas is 5–20%.

3. The method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor according to claim 1, characterized in that: The chemical composition percentages of the hot-rolled raw material are as follows: C: 0.028%, Si: 2.95%, Mn: 0.21%, Als: 0.016%, Cu: 0.35%, P: 0.012%, S: 0.007%, N: 0.0092%, Sb: 0.0351%, with the remainder being Fe and impurities.

4. The method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor according to claim 1, characterized in that: The chemical composition percentages of the hot-rolled raw material are as follows: C: 0.035%, Si: 3.05%, Mn: 0.21%, Als: 0.017%, Cu: 0.30%, P: 0.013%, S: 0.008%, N: 0.0089%, Sb: 0.0427%, with the remainder being Fe and impurities.

5. The method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor according to claim 1, characterized in that: The chemical composition percentages of the hot-rolled raw material are as follows: C: 0.031%, Si: 3.28%, Mn: 0.20%, Als: 0.014%, Cu: 0.39%, P: 0.013%, S: 0.007%, N: 0.0102%, Sb: 0.0329%, with the remainder being Fe and impurities.

6. The method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor according to claim 1, characterized in that: By employing the synergistic effect of Cu-Sb composite inhibitors, the goal of increasing magnetic induction intensity is achieved, with the average magnetic induction of high-temperature oriented silicon steel reaching over 1.88T under the same specifications.

7. The method for improving the magnetic induction of high-temperature oriented silicon steel using a Cu-Sb composite inhibitor according to claim 6, characterized in that: Iron loss P 1.7 / 50 Reduced to below 0.96w / kg.

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