Method for researching corrosion resistance of non-oriented silicon steel

Abstract

The invention discloses a research method for corrosion resistance of non-oriented silicon steel, which comprises the following steps: (1) respectively controlling the content of S to be 0.35%, 0.75% and 1.25% in a steelmaking process, and carrying out hot rolling, acid continuous rolling and annealing processes on a casting blank to obtain a finished product; sampling finished products with different S contents, and detecting magnetic properties and corrosion proportions; (2) respectively setting annealing temperatures corresponding to different S contents, and researching finished product samples obtained under different annealing temperature conditions to detect magnetic properties and corrosion ratios of different salt spray times; and (3) the influence of the annealing speed is researched under the conditions that the annealing temperatures are 820 DEG C, 840 DEG C and 850 DEG C respectively. Through a control method for adjusting chemical components, the annealing temperature and the annealing production speed, the influence of the S content, the annealing temperature and the annealing speed is researched from the aspects of the corrosion proportion and the magnetic performance of a salt-spray corrosion test, and the relation between the S content and the corrosion resistance and between annealing process parameters and the corrosion resistance is determined.

Description

Technical Field

[0001] The invention belongs to the technical field of corrosion resistance of non-oriented silicon steel, and in particular relates to a method for studying the corrosion resistance of non-oriented silicon steel. Background Art

[0002] As the core material for manufacturing various types of motor cores, the performance of non-oriented silicon steel determines the energy consumption and life of the motor. With the improvement of the level of automation in life, the application fields of motors have expanded rapidly, including home appliances, wind power, new energy vehicles, industrial motors and other industries, and the application environment is very complex. At the same time, with the continuous improvement of energy-saving and consumption-reduction requirements, the comprehensive performance requirements for non-oriented silicon steel have gradually increased. Among them, corrosion resistance is very important for motors used in high temperature, humid and salty environments. Good corrosion resistance can increase the life of the motor and avoid safety accidents. Existing studies have mainly focused on the effect of coating performance on corrosion resistance, ignoring the effect of substrate corrosion resistance. Therefore, by studying and improving the overall corrosion resistance of non-oriented silicon steel, it is possible to increase the life of the motor, reduce production costs, improve the comprehensive performance of non-oriented silicon steel, and broaden its application scenarios.

[0003] At present, application number 202011372065.0 has announced a non-oriented silicon steel sheet with excellent corrosion resistance and a production method for high-efficiency motors, focusing on the composition control and production process parameter control of non-oriented silicon steel sheets for high-efficiency motors. The present invention elaborates on the role of different chemical components, and determines the content in combination with the influence on magnetic properties and corrosion resistance. By controlling the heating temperature of the ingot, the thickness of the hot-rolled plate, the final rolling temperature, the coiling temperature and the annealing process parameters, the plate surface quality and magnetic properties are guaranteed. By adding alloying elements Sn and Cu and matching appropriate production process parameters, non-oriented silicon steel with good comprehensive performance for high-efficiency motors is obtained.

[0004] Application No. 202310325599.5 discloses an ultra-thin corrosion-resistant silicon steel strip and its preparation method, and details the production process of the ultra-thin silicon steel strip and the preparation process of the insulating impregnated glue. The invention focuses on the pretreatment, activation, preparation of insulating coating by impregnation and pulling method, magnetic thermal coupling treatment, and cooling process of the silicon steel strip to obtain an ultra-thin corrosion-resistant silicon steel strip, which has the characteristics of low dislocation density, small residual stress, and good soft magnetic properties. Summary of the invention

[0005] The purpose of the present invention is to provide a method for studying the corrosion resistance of non-oriented silicon steel. By adjusting the control method of chemical composition, annealing temperature and annealing production speed, the influence of Si content, annealing temperature and annealing speed is studied from the aspects of corrosion ratio and magnetic properties in salt spray corrosion test, the relationship between Si content and annealing process parameters and corrosion resistance is determined, and guidance is provided for the industrial production of non-oriented silicon steel with excellent comprehensive performance.

[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 studying the corrosion resistance of non-oriented silicon steel, comprising:

[0008] (1) Si content

[0009] During the steelmaking process, the Si content was controlled at 0.35%, 0.75%, and 1.25%, and the finished products were obtained after the ingots were hot rolled, acid continuous rolled, and annealed. The finished products with different Si contents were sampled and tested for magnetic properties and corrosion ratio (24 hours).

[0010] (2) Annealing temperature

[0011] Corresponding to different Si contents, the annealing temperatures were set to 800-840℃, 820-860℃ and 830-870℃ respectively. The finished products obtained under different annealing temperature conditions were sampled to test the magnetic properties and the corrosion ratio of different salt spray times (24h);

[0012] (3) Annealing speed

[0013] Under the conditions of annealing temperatures of 820℃, 840℃ and 850℃, the influence of annealing speed was studied. The annealing speeds were set to 80m / min, 90m / min and 100m / min, respectively. The finished products obtained under different annealing speeds were sampled and tested for magnetic properties and corrosion ratio of different salt spray times (24h).

[0014] Furthermore, the chemical composition of the non-oriented silicon steel is as follows by mass percentage: 0.0025% C, 0.25-1.35% Si, 0.25-0.45% Mn, 0.030% P, 0.002% S, 0.30-0.45% Al s, 0.0025% N, 0.0020% O, 0.0025% Ti, and the rest is Fe and unavoidable impurities.

[0015] Furthermore, the non-oriented silicon steel has a thickness of 0.50 mm and a ferrite structure.

[0016] Furthermore, the Si content is controlled to be 1.2-1.3%, the annealing temperature is 860-870°C, and the annealing speed is 80-100 m / min.

[0017] Furthermore, the Si content is controlled to be 1.25%.

[0018] Furthermore, the annealing temperature is controlled to be 860°C or 870°C.

[0019] Further, the annealing speed is controlled to 80 or 100 m / min;

[0020] A method for improving the corrosion resistance of non-oriented silicon steel is also provided, comprising: controlling the Si content to 1.2-1.3%, the annealing temperature to 860-870°C, and the annealing speed to 80-100 m / min;

[0021] The chemical composition of the non-oriented silicon steel is as follows: 0.0025% C, 0.25-1.35% Si, 0.25-0.45% Mn, 0.030% P, 0.002% S, 0.30-0.45% Al s, 0.0025% N, 0.0020% O, 0.0025% Ti, and the rest is Fe and unavoidable impurities.

[0022] Compared with the prior art, the beneficial technical effects of the present invention are:

[0023] The invention provides guidance for the industrial production of non-oriented silicon steel with good comprehensive performance by exploring the influence of Si content, annealing temperature and annealing speed on the corrosion resistance and magnetic properties of non-oriented silicon steel. DETAILED DESCRIPTION

[0024] In order to better explain the present invention, the main contents of the present invention are further illustrated below in conjunction with specific embodiments.

[0025] Table 1 shows the process parameters during normalization treatment of Examples 1-5 and Comparative Example 1.

[0026] Table 1 Continuous annealing process parameters of various embodiments of the present invention and comparative examples

[0027] Si content wt% Annealing temperature℃ Annealing speed m / min Comparative Example 1 0.50 810 70 Example 1 0.35 810 70 Example 2 0.35 830 100 Example 3 0.75 830 80 Example 4 0.75 860 90 Example 5 1.25 860 80 Example 6 1.25 870 100

[0028] Note: The other components of each embodiment and comparative example are the same.

[0029] The salt spray corrosion ratio and magnetic properties of the finished products prepared by the process of the above-mentioned embodiments 1-6 and comparative example 1 are shown in Table 2.

[0030] Table 2 Performance results of the products prepared in various embodiments and comparative examples of the present invention

[0031]

[0032] It can be seen from Table 2 that Si content, annealing temperature and annealing speed have an impact on the corrosion resistance and magnetic properties of non-oriented silicon steel, and there is an interactive relationship. With the increase of Si content, the corrosion resistance shows an overall improvement trend. Since Si can increase the resistivity, therefore, with the increase of Si content, the iron loss shows a downward trend. Under the condition of the same Si content, increasing the annealing speed needs to be coordinated with a high annealing temperature to ensure the formation of a complete coating and improve the corrosion resistance and magnetic properties.

[0033] The embodiments described above are only descriptions of the preferred modes 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 studying the corrosion resistance of non-oriented silicon steel, characterized in that: include: (1) Si content During the steelmaking process, the Si content was controlled at 0.35%, 0.75%, and 1.25%, and the finished products were obtained after the ingots were hot rolled, acid continuous rolled, and annealed. The finished products with different Si contents were sampled and tested for magnetic properties and corrosion ratio. (2) Annealing temperature Corresponding to different Si contents, the annealing temperatures were set to 800-840℃, 820-860℃ and 830-870℃ respectively. The finished products obtained under different annealing temperature conditions were sampled to test the magnetic properties and the corrosion ratio of different salt spray times; (3) Annealing speed Under the conditions of annealing temperatures of 820℃, 840℃ and 850℃, the influence of annealing speed was studied. The annealing speeds were set to 80m / min, 90m / min and 100m / min, respectively. The finished products obtained under different annealing speeds were sampled and tested for magnetic properties and corrosion ratios at different salt spray times.

2. The method for studying the corrosion resistance of non-oriented silicon steel according to claim 1, characterized in that: The chemical composition of the non-oriented silicon steel is as follows: 0.0025% C, 0.25-1.35% Si, 0.25-0.45% Mn, 0.030% P, 0.002% S, 0.30-0.45% Als, 0.0025% N, 0.0020% O, 0.0025% Ti, and the rest is Fe and unavoidable impurities.

3. The method for studying the corrosion resistance of non-oriented silicon steel according to claim 2, characterized in that: The non-oriented silicon steel has a thickness of 0.50 mm and a ferrite structure.

4. The method for studying the corrosion resistance of non-oriented silicon steel according to claim 1, characterized in that: The Si content is controlled to be 1.2-1.3%, the annealing temperature is 860-870°C, and the annealing speed is 80-100m / min.

5. The method for studying the corrosion resistance of non-oriented silicon steel according to claim 4, characterized in that: The Si content is controlled to be 1.25%.

6. The method for studying the corrosion resistance of non-oriented silicon steel according to claim 4, characterized in that: The annealing temperature is controlled at 860°C or 870°C.

7. The method for studying the corrosion resistance of non-oriented silicon steel according to claim 6, characterized in that: Control the annealing speed to 80 or 100 m / min.

8. A method for improving the corrosion resistance of non-oriented silicon steel, characterized in that: include: Control the Si content to 1.2-1.3%, the annealing temperature to 860-870°C, and the annealing speed to 80-100m / min; The chemical composition of the non-oriented silicon steel is as follows: 0.0025% C, 0.25-1.35% Si, 0.25-0.45% Mn, 0.030% P, 0.002% S, 0.30-0.45% Als, 0.0025% N, 0.0020% O, 0.0025% Ti, and the rest is Fe and unavoidable impurities.

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