CN106282779B - One kind is orientated high silicon steel thin belt and preparation method thereof - Google Patents

Abstract

The invention relates to an oriented high-silicon steel strip and a preparation method thereof. The technical solution is: the chemical composition of the oriented high silicon steel strip is: Si is 5.5~6.8wt%; Cu is 0.3~0.6wt%; Al is 0.1~0.3wt%; S is 0.01~0.015wt%; N is 0.005 ~0.01wt%; the rest is Fe and unavoidable impurities. Smelting according to the chemical composition of oriented high-silicon steel strips, casting into slabs at 1300~1650°C, hot rolling the slabs at 1000~1200°C into hot-rolled sheets with a thickness of 0.8~1.5mm. The hot-rolled sheet is normalized, warm rolled at 150~450°C to 0.3~0.6mm, cold rolled at room temperature to 0.1~0.3mm, kept at 700~1200°C for 1~16h, and cooled with the furnace to obtain the orientation High silicon steel thin strip. The temperature of the normalization treatment is 900-1100° C., the temperature is kept for 3-15 minutes, and the cooling method is water quenching. The invention has the characteristics of simple process and short flow; the prepared oriented high-silicon steel thin strip has low iron loss and high magnetic induction.

Description

A kind of oriented high-silicon steel strip and its preparation method

technical field

The invention belongs to the technical field of high silicon steel strips. In particular, it relates to an oriented high-silicon steel strip and a preparation method thereof.

technical background

High-silicon steel generally refers to the iron-silicon alloy with a Si content of 6.5wt%. Due to its excellent magnetic properties such as high resistivity, low magnetostriction coefficient, and low iron loss at high frequencies, high-silicon steel is especially suitable for making high-speed high-frequency motors, transformers, reactors, and shielding components, which is conducive to the realization of small equipment high speed, low energy consumption and low noise. However, according to the Fe-Si phase diagram, when the Si content exceeds 4.5wt%, two ordered structures, B2 and D0 ₃ , will appear, causing the plasticity of the alloy to drop sharply, making it difficult to form by rolling, making it difficult for high-silicon steel to adopt rolling. method for industrial production.

At present, only Japan’s JFE company in the world uses chemical vapor deposition (CVD) to industrially produce high-silicon steel. Its high-silicon steel products include gradient high-silicon steel (JNHF-Core) and full-thickness high-silicon steel (JNEX-Core). All high silicon steels are non-oriented. Due to the complex process of CVD method, serious equipment corrosion and environmental pollution, and the thin plate prepared by rolling method has the advantages of uniform composition and good surface quality, and has high industrial application value, so rolling method has attracted the attention of those skilled in the art .

In recent years, the high-silicon steels prepared by the rolling method are mainly non-oriented high-silicon steels, but there are few reports on the preparation of oriented high-silicon steels. This is because the preparation process of grain-oriented silicon steel is complex, the alloy composition is strictly controlled, the size, distribution, and quantity of inhibitor particles are accurately controlled, and the texture control has reached an extreme level. Increasing the silicon content will delay or hinder the development of secondary recrystallization, and stronger inhibitors are needed to suppress the initial grain growth, which undoubtedly increases the difficulty of preparing oriented high-silicon steel, so the production process of traditional oriented silicon steel cannot be completely applied. , needs to be improved on the basis of the original process.

"A method for preparing oriented high-silicon steel sheet by rolling" (CN104120233A), by adding C element and adding various inhibitor elements at the same time, adopting smelting, hot rolling, normalization treatment, one-time rolling, decarburization annealing and intermediate annealing , to obtain oriented high-silicon steel plate. In this method, grain-oriented high-silicon steel is prepared by adding various inhibitors, but the preparation process is relatively complicated due to the various inhibitors added. Due to the high content of added C, this method must undergo decarburization annealing treatment. It is well known in the industry that if the C content in high silicon steel is too high, it is easy to segregate to form Fe ₃ C, which is extremely unfavorable to the plasticity of high silicon steel. The preparation of high silicon steel with serious brittleness problem is more difficult.

"A preparation method for oriented high-silicon steel" (CN104372238A), through strip continuous casting, hot rolling, warm rolling, cold rolling, recrystallization annealing and purification annealing to obtain oriented high-silicon steel with high magnetic induction. In this method, various alloying elements such as Mn, Al, V, Nb, S, and N are added, and the C content is controlled at 0.001-0.003%. The C content of this method is not high, so the decarburization process before high-temperature annealing is omitted. Although the difficulty of the primary recrystallization process is simplified, the C element will deteriorate the magnetic properties of high-silicon steel to a certain extent, especially the iron loss. Therefore, the iron loss value of the obtained grain-oriented high-silicon steel is relatively high, especially the iron loss P _1.0/400 of medium and high frequency is 6.75~9.5W/kg.

"A method for preparing oriented high-silicon steel sheets by rolling" (CN104911322A), through hot rolling, normalization, warm rolling, cold rolling, decarburization annealing, nitriding treatment, and secondary recrystallization annealing to obtain oriented high-silicon steel sheets, In this method, oil quenching is adopted in the processes of hot rolling, normalization and warm rolling. This method adds a small amount of Mn, Al, N, S and C elements, and the composition is relatively simple, but due to the lack of alloying elements, the inhibitor's inhibitory ability is insufficient, so after the decarburization annealing is completed, it must undergo nitriding treatment to obtain high orientation. Silicon steel sheet. Although the composition of this method is relatively simple, the process is relatively complicated, and the obtained oriented high silicon steel B ₈ =1.55~1.61T, the iron loss is mainly reflected in the low frequency range, and the iron loss value in the high frequency range is not given. Compared with ordinary silicon steel, high-silicon steel has the advantage of low iron loss, especially high-frequency low iron loss, so it does not reflect the performance advantages of high-silicon steel and ordinary silicon steel.

Contents of the invention

The invention aims to overcome the defects of the prior art, and aims to provide a method for preparing a high-silicon steel thin strip with simple process and short process flow. The high-silicon steel thin strip prepared by the method has low iron loss and high magnetic induction.

In order to achieve the above object, the technical solution adopted in the present invention is: the chemical composition of the oriented high silicon steel strip is: Si is 5.5~6.8wt%; Cu is 0.3~0.6wt%; Al is 0.1~0.3wt%; S N is 0.01~0.015wt%; N is 0.005~0.01wt%; the rest is Fe and unavoidable impurities.

The preparation method of the oriented high-silicon steel strip is: smelting according to the chemical composition of the oriented high-silicon steel strip, casting it into a slab at 1300-1650°C, heating the slab at 1000-1200°C Rolled into a hot-rolled sheet with a thickness of 0.8~1.5mm. The hot-rolled sheet is subjected to normalization treatment, and the hot-rolled sheet after the normalization treatment is warm-rolled to 0.3-0.6mm at 150-450°C to obtain a warm-rolled sheet; the warm-rolled sheet is heated at room temperature Cold rolling to 0.1~0.3mm, that is, high silicon steel thin strip. The high-silicon steel strip is kept at 700-1200° C. for 1-16 hours, and cooled in a furnace to obtain an oriented high-silicon steel strip.

The temperature of the normalization treatment is 900-1100° C., and the holding time of the normalization treatment is 3-15 minutes; the cooling method of the normalization treatment is water quenching.

Owing to adopting above-mentioned technical scheme, the present invention has following positive effect compared with prior art:

The invention can obtain oriented high-silicon steel strip through simple smelting, hot rolling, normalization, warm rolling, cold rolling and finished product annealing. The composition of the present invention is simple, the smelting process is easy to control, and due to the reasonable matching of the composition, no addition of C element is required, so the decarburization annealing process is omitted, and the preparation process is greatly simplified. The preparation of oriented high-silicon steel thin strips by rolling has the characteristics of simple process, short process and low cost.

The present invention not only improves the plasticity of high-silicon steel by adding trace amounts of Cu and Al, but also the precipitation of Cu, Cu ₂ S and CuS composed of Cu and S, and the precipitation of AlN will act as inhibitors, thus promoting Goss The selective growth of texture. The normalization process is not only conducive to the fine dispersion and precipitation of inhibitors, but also the water quenching used in the normalization process is beneficial to reduce the long-range order of high silicon steel, which is beneficial to the rolling of high silicon steel in warm rolling and cold rolling. Therefore, considering the brittleness of high-silicon steel, the addition of alloy elements and normalization treatment in the present invention are not only to improve the plasticity of high-silicon steel, but also to obtain sufficient inhibitors to promote the abnormal growth of Goss grains. After the finished product is annealed, the oriented high-silicon steel strip with low iron loss and high magnetic induction can be obtained. The magnetic properties of the oriented high-silicon steel strip: P _1.0/1k =25~55W/kg, B ₈ =1.45~1.67T.

Therefore, the invention has the characteristics of simple process and short process, and the prepared oriented high-silicon steel thin strip has low iron loss and high magnetic induction.

Detailed ways

The present invention will be further described below in combination with specific embodiments, which are not intended to limit the protection scope thereof.

Example 1

An oriented high-silicon steel strip and a preparation method thereof. The chemical composition of the oriented high silicon steel strip is: Si is 6.6~6.8wt%; Cu is 0.5~0.6wt%; Al is 0.1~0.2wt%; S is 0.012~0.015wt%; N is 0.005~0.007wt% %; the rest is Fe and unavoidable impurities.

The preparation method of the oriented high-silicon steel strip is: smelting according to the chemical composition of the oriented high-silicon steel strip, casting it into a slab at 1550-1650°C, and heating the slab at 1100-1200°C Rolled into a hot-rolled plate with a thickness of 1.3~1.5mm. The hot-rolled sheet is subjected to normalization treatment, and the hot-rolled sheet after the normalization treatment is warm-rolled to 0.5-0.6mm at 350-450°C to obtain a warm-rolled sheet; the warm-rolled sheet is heated at room temperature Cold rolling to 0.2~0.3mm, that is, high-silicon steel thin strip. The high-silicon steel strip is kept at 1100-1200° C. for 5-10 hours, and then cooled in a furnace to obtain an oriented high-silicon steel strip.

The temperature of the normalization treatment is 1000-1100° C., and the holding time of the normalization treatment is 3-5 minutes; the cooling method of the normalization treatment is water quenching.

The oriented high-silicon steel thin strip prepared in this example has low iron loss and high magnetic induction, and the magnetic properties are tested: P _1.0/1k =40~55W/kg, B ₈ =1.60~1.67T.

Example 2

An oriented high-silicon steel strip and a preparation method thereof. The chemical composition of the oriented high silicon steel strip is: Si is 6.3~6.6wt%; Cu is 0.5~0.6wt%; Al is 0.2~0.3wt%; S is 0.012~0.015wt%; N is 0.007~0.0099wt% %; the rest is Fe and unavoidable impurities.

The preparation method of the oriented high-silicon steel strip is: smelting according to the chemical composition of the oriented high-silicon steel strip, casting it into a slab at 1500-1650°C, heating the slab at 1000-1100°C Rolled into a hot-rolled sheet with a thickness of 1.2~1.3mm. The hot-rolled sheet is subjected to normalization treatment, and the hot-rolled sheet after the normalization treatment is warm-rolled to 0.4-0.5mm at 350-450°C to obtain a warm-rolled sheet; the warm-rolled sheet is heated at room temperature Cold rolling to 0.2~0.3mm, that is, high-silicon steel thin strip. The high-silicon steel strip is kept at 900-1100°C for 12-16 hours, and then cooled in the furnace to obtain an oriented high-silicon steel strip.

The temperature of the normalization treatment is 1000-1100° C., the holding time of the normalization treatment is 5-8 minutes; the cooling method of the normalization treatment is water quenching.

The oriented high-silicon steel thin strip prepared in this example has low iron loss and high magnetic induction, and the magnetic properties are tested: P _1.0/1k =35~40W/kg, B ₈ =1.55~1.60T.

Example 3

An oriented high-silicon steel strip and a preparation method thereof. The chemical composition of the oriented high silicon steel strip is: Si is 6.0~6.3wt%; Cu is 0.4~0.5wt%; Al is 0.1~0.2wt%; S is 0.01~0.012wt%; N is 0.007~0.009wt% %; the rest is Fe and unavoidable impurities.

The preparation method of the oriented high-silicon steel strip is: smelting according to the chemical composition of the oriented high-silicon steel strip, casting it into a slab at 1300-1400°C, heating the slab at 1000-1100°C Rolled into a hot-rolled sheet with a thickness of 1.0~1.1mm. The hot-rolled sheet is subjected to normalization treatment, and the hot-rolled sheet after the normalization treatment is warm-rolled to 0.3-0.4mm at 250-350°C to obtain a warm-rolled sheet; the warm-rolled sheet is heated at room temperature Cold rolling to 0.1~0.2mm, that is, high-silicon steel thin strip. The high-silicon steel strip is kept at 900-1100° C. for 1-5 hours, and cooled in a furnace to obtain an oriented high-silicon steel strip.

The temperature of the normalization treatment is 900-1000° C., and the holding time of the normalization treatment is 8-12 minutes; the cooling method of the normalization treatment is water quenching.

The oriented high-silicon steel thin strip prepared in this example has low iron loss and high magnetic induction, and the magnetic properties are tested: P _1.0/1k =30~35W/kg, B ₈ =1.5~1.55T.

Example 4

An oriented high-silicon steel strip and a preparation method thereof. The chemical composition of the oriented high silicon steel strip is: Si is 5.5~6.0wt%; Cu is 0.3~0.4wt%; Al is 0.2~0.3wt%; S is 0.01~0.012wt%; N is 0.008~0.01wt% %; the rest is Fe and unavoidable impurities.

The preparation method of the oriented high-silicon steel strip is: smelting according to the chemical composition of the oriented high-silicon steel strip, casting it into a slab at 1400-1500°C, heating the slab at 1100-1200°C Rolled into a hot-rolled sheet with a thickness of 0.8~1.0mm. The hot-rolled sheet is subjected to normalization treatment, and the hot-rolled sheet after the normalization treatment is warm-rolled to 0.3-0.4mm at 150-250°C to obtain a warm-rolled sheet; the warm-rolled sheet is heated at room temperature Cold rolling to 0.1~0.2mm, that is, high-silicon steel thin strip. The high-silicon steel strip is kept at 700-900°C for 8-12 hours, and cooled in the furnace to obtain an oriented high-silicon steel strip.

The temperature of the normalization treatment is 900-1000° C., and the holding time of the normalization treatment is 12-15 minutes; the cooling method of the normalization treatment is water quenching.

The oriented high-silicon steel thin strip prepared in this example has low iron loss and high magnetic induction, and the magnetic properties are tested: P _1.0/1k =25~30W/kg, B ₈ =1.45~1.507T.

Compared with the prior art, this specific embodiment has the following positive effects:

This specific implementation mode can obtain oriented high-silicon steel strips through simple smelting, hot rolling, normalization, warm rolling, cold rolling, and finished product annealing. . The composition of this specific embodiment is simple, the smelting process is easy to control, and due to the reasonable combination of the composition, no addition of C element is required, so the decarburization annealing process is omitted, and the preparation process is greatly simplified. The preparation of oriented high-silicon steel thin strips by rolling has the characteristics of simple process, short process and low cost.

In this specific embodiment, by adding trace amounts of Cu and Al, not only the plasticity of high-silicon steel is improved, but also Cu elemental precipitation, Cu ₂ S, CuS precipitation composed of Cu and S, and AlN precipitation will act as inhibitors, thereby promoting The merit-based growth of the Goss texture. The normalization process is not only conducive to the fine dispersion and precipitation of inhibitors, but also the water quenching used in the normalization process is beneficial to reduce the long-range order of high silicon steel, which is beneficial to the rolling of high silicon steel in warm rolling and cold rolling. Therefore, considering the brittleness of high-silicon steel, the addition of alloying elements and normalization treatment in this specific embodiment are not only to improve the plasticity of high-silicon steel, but also to obtain sufficient inhibitors to promote the abnormal growth of Goss grains. After the finished product is annealed, the oriented high-silicon steel strip with low iron loss and high magnetic induction can be obtained. The magnetic properties of the oriented high-silicon steel strip are: P _1.0/1k =25~55W/kg, B ₈ =1.45~1.67T.

Therefore, this specific embodiment has the characteristics of simple process and short flow; the oriented high silicon steel thin strip prepared by this method has low iron loss and high magnetic induction.

Claims (2)

1. A preparation method for an orientation high-silicon steel strip, characterized in that the chemical composition of the orientation high-silicon steel strip is: Si is 5.5 to 6.8wt%, Cu is 0.3 to 0.6wt%, and Al is 0.1 to 0.3wt% %, S is 0.01-0.015wt%, N is 0.005-0.01wt%, and the rest is Fe and unavoidable impurities; The preparation method of the oriented high-silicon steel strip is: smelting according to the chemical composition of the oriented high-silicon steel strip, casting it into a slab at 1300-1650°C, heating the slab at 1000-1200°C Rolling into a hot-rolled sheet with a thickness of 0.8-1.5 mm; carrying out normalization treatment on the hot-rolled sheet, and warm-rolling the normalized hot-rolled sheet to 0.3-0.6 mm under the condition of 150-450° C. Rolling the plate; cold rolling the warm rolled plate to 0.1-0.3 mm at room temperature to obtain a high-silicon steel strip; keeping the high-silicon steel strip at 700-1200°C for 1-16 hours, and cooling in the furnace , that is, oriented high-silicon steel strip; The temperature of the normalization treatment is 900-1100° C., and the holding time of the normalization treatment is 3-15 minutes; the cooling method of the normalization treatment is water quenching. 2. An orientation high silicon steel strip, characterized in that the orientation high silicon steel strip is an orientation high silicon steel strip prepared according to the preparation method of the orientation high silicon steel strip according to claim 1.