Dual-oriented high silicon steel based on rolling method combined with surface energy annealing and preparation method thereof

Abstract

The present invention provides a dual-oriented high-silicon steel based on rolling combined with surface energy annealing and a preparation method thereof. The preparation method sequentially hot-rolls, pickles, warm-rolls three times, performs two intermediate anneals, and finally anneals a silicon-containing ingot to produce a dual-oriented high-silicon steel strip. The three warm-rolling steps combined with the two intermediate anneals increase the cubic texture percentage. The final annealing utilizes the low surface energy of {100} to induce abnormal growth of cubic-oriented grains, resulting in a finished dual-oriented high-silicon steel with a sharp cubic texture. The present invention utilizes the surface energy effect of the cubic orientation by hot-rolling, warm-rolling three times, and annealing the high-silicon steel to produce low-iron-loss, high-magnetic-induction non-oriented electrical steel. This method fully utilizes the "plasticization and toughening rolling technology" of high-silicon steel, optimizing the recrystallization texture of the high-silicon steel through surface energy annealing while ensuring formability, resulting in a finished dual-oriented high-silicon steel with a sharp cubic texture.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material preparation, and in particular to a dual-oriented high-silicon steel based on a rolling method combined with surface energy annealing and a preparation method thereof. Background Art

[0002] Although Fe-6.5wt% Si alloy has excellent soft magnetic properties and is an ideal material for making low iron loss and vibration-free cores, it is difficult to prepare Fe-6.5wt% Si thin strips using conventional forming methods due to its poor room temperature plasticity. Compared with ordinary silicon steel, the magnetic properties of high silicon steel are more sensitive to recrystallization texture. However, due to its high hardness and brittleness, research on high silicon steel has long focused on how to improve its processing and forming. Although there have been many studies on the texture of high silicon steel, there has been little progress, and there is still much room for improvement in the magnetic properties of high silicon steel. Research on the control of high silicon steel texture has mainly focused on two directions: one is to use the low-temperature nitriding technology of Fe-3.0%Si oriented silicon steel to overcome the unique brittleness and surface oxide layer structure of high silicon steel, so that the Gaussian oriented grains grow abnormally and prepare oriented high silicon steel with strong Gaussian texture characteristics; the other is to use ND type columnar crystals to retain the {100} texture to prepare λ( <001> / / ND) non-oriented high silicon steel with recrystallization texture characteristics. The preparation process of oriented silicon steel is complex, the alloy composition is strictly controlled, the size, distribution and quantity of inhibitor particles are accurately controlled, and especially the texture control has reached the ultimate level. The intrinsic brittleness of high silicon steel forces the use of warm rolling system in the forming process of high silicon steel. This rolling system weakens the formation of shear bands and is not conducive to the retention of Gossian oriented grains. Therefore, for high silicon steel, there are inherent disadvantages in the preparation of oriented high silicon steel with Gossian texture as the main feature. The production of non-oriented silicon steel requires strict control of γ ( <111> / / ND) fiber texture components, but the current production technology of non-oriented electrical steel is difficult to achieve γ ( <111> / / ND) effective control of recrystallization texture to obtain strong λ ( <001> / / ND) textured silicon steel sheets are even more difficult.

[0003] Double oriented high silicon steel refers to the finished product with cubic ({100} <001> Compared with the single easy magnetization direction along the rolling direction of general oriented silicon steel, the cubic texture in the bi-oriented high silicon steel can provide two most easily magnetized directions on the surface of the steel plate at the same time. <001> Crystal orientation. Therefore, a cubic texture is the ideal recrystallization texture for both non-oriented silicon steel used in rotating magnetic fields and oriented silicon steel used in directional magnetic fields. Patents CN 201710402819.4 and CN201980078053.6, respectively, utilize twin-roller thin strip casting technology and the addition of alloying elements to increase the cubic component after annealing. However, the {100} textures produced by these methods have a limited cubic content, making them difficult to use for dual-orientation applications. Surface energy-induced secondary recrystallization of cubic-oriented grains is a relatively effective method for achieving a strong cubic texture.

[0004] Therefore, in view of the unparalleled magnetic properties of the dual-oriented high silicon steel, the inherent brittleness of the high silicon steel material and the use of multiple-pass recovery rolling with small deformation, the silicon steel strip product after rolling is thinner and has obvious surface effect, and the high silicon steel "gradual toughening rolling technology" is fully utilized to weaken the γ ( <111> / / ND) texture component, increasing the cubic component, and later combining surface energy annealing to induce secondary recrystallization of cubic-oriented grains, to prepare a finished product of dual-oriented high-silicon steel with a sharp cubic texture to address the shortcomings of the existing technology and solve or alleviate one or more of the above-mentioned problems. Summary of the Invention

[0005] In light of this, the present invention provides a dual-oriented high-silicon steel based on rolling combined with surface energy annealing and a method for preparing the same. The dual-oriented high-silicon steel is prepared by combining plasticizing and toughening rolling with surface energy annealing. By hot rolling, three warm rolling cycles, and annealing the high-silicon steel, the surface energy effect of cubic orientation is utilized to produce low-iron-loss, high-magnetic-induction non-oriented electrical steel. This method fully utilizes the "plasticizing and toughening rolling" technology of high-silicon steel, optimizing the recrystallization texture of the high-silicon steel through surface energy annealing while ensuring formability, resulting in a finished dual-oriented high-silicon steel with a sharp cubic texture.

[0006] On the one hand, the present invention provides a method for preparing a dual-oriented high-silicon steel based on a rolling method combined with surface energy annealing, wherein the preparation method comprises sequentially hot rolling, pickling, three warm rollings, two intermediate annealings, and a final annealing on a silicon-containing square ingot, thereby preparing a dual-oriented high-silicon steel thin strip;

[0007] Among them, three warm rolling steps combined with two intermediate annealing steps are used to increase the percentage of cubic texture;

[0008] The final annealing utilizes the low surface energy of {100} to induce the abnormal growth of cubic oriented grains, and the finished product is a dual-oriented high-silicon steel with a sharp cubic texture.

[0009] According to the above aspects and any possible implementation, there is further provided an implementation, wherein the silicon content in the silicon-containing ingot is 6.0% to 6.5%.

[0010] According to the aspects and any possible implementation methods described above, an implementation method is further provided, wherein the hot rolling adopts lubrication rolling, the hot rolling temperature is controlled at 1050℃~1150℃, multiple passes of small deformation rolling are carried out within this temperature range, the reduction of each pass is controlled at 10%~25%, and the total hot rolling reduction rate is controlled at 50%~90%.

[0011] According to the above aspects and any possible implementation, there is further provided an implementation, wherein in the three warm rolling processes, the temperature of the first warm rolling process is 700°C to 600°C.

[0012] According to the above aspects and any possible implementation, there is further provided an implementation, wherein in the three warm rolling processes, the temperature of the second warm rolling process is 600°C to 500°C.

[0013] According to the above aspects and any possible implementation, there is further provided an implementation, wherein in the three warm rolling processes, the temperature of the third warm rolling process is 500°C to 400°C.

[0014] According to the above aspects and any possible implementation, there is further provided an implementation, wherein the reduction ratio of each warm rolling pass in the three warm rolling passes is controlled within a range of 40% to 70%.

[0015] According to the above aspects and any possible implementation, there is further provided an implementation, wherein the intermediate annealing temperature is 800° C. to 850° C., and the texture of the finished plate is mainly cubic texture.

[0016] According to the above aspects and any possible implementation, a dual-oriented high-silicon steel based on a rolling method combined with surface energy annealing is further provided, which is prepared by the preparation method. The chemical composition of the dual-oriented high-silicon steel is as follows: Si: 6.3-6.5wt%, Mn: 0.05-0.8wt%, P: 0.005-0.009wt%, C: < 0.01wt%, S: < 0.01wt%, and the rest is Fe and unavoidable impurities.

[0017] According to the above aspects and any possible implementation, a further implementation is provided, wherein the dual-oriented high silicon steel P 2 / 1000 Between 0.56W / kg and 0.92W / kg, P 10 / 400 Between 3.18W / kg and 4.27W / kg.

[0018] Compared with the prior art, the present invention can achieve the following technical effects:

[0019] The high-silicon steel prepared by the present invention has soft magnetic properties of low iron loss, high magnetic permeability and low noise; as a soft magnetic alloy widely used in the power electronics industry, it is suitable for making iron cores of generators, motors, transformers and other instruments, and can meet the requirements of high efficiency, energy saving, miniaturization and high frequency of power electronic equipment.

[0020] Of course, any product implementing the present invention does not necessarily need to achieve all of the above-mentioned technical effects at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a flow chart of a method for preparing dual-oriented high silicon steel based on a rolling method combined with surface energy annealing according to the present invention;

[0023] Figure 2 This is the microstructure of the dual-oriented high silicon steel after high temperature annealing in Example 5 of the present invention;

[0024] Figure 3 This is a 45° ODF diagram of the dual-oriented high silicon steel after high temperature annealing in Example 5 of the present invention;

[0025] Figure 4 This is a grain orientation imaging diagram of the dual-oriented high silicon steel after high-temperature annealing in Example 5 of the present invention. DETAILED DESCRIPTION

[0026] In order to better understand the technical solution of the present invention, the embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0027] It should be understood that the embodiments described are only a portion of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative work are within the scope of protection of the present invention.

[0028] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "an", "the" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise.

[0029] like Figure 1As shown, the present invention provides a method for preparing dual-oriented high-silicon steel based on a rolling method combined with surface energy annealing, wherein the preparation method sequentially performs hot rolling, pickling, three warm rollings, two intermediate annealings, and final annealing on a silicon-containing square ingot, thereby preparing a dual-oriented high-silicon steel thin strip;

[0030] Among them, three warm rolling steps combined with two intermediate annealing steps are used to increase the percentage of cubic texture;

[0031] The final annealing utilizes the low surface energy of {100} to induce the abnormal growth of cubic oriented grains, and the finished product is a dual-oriented high-silicon steel with a sharp cubic texture.

[0032] The silicon content in the silicon-containing ingot is 6.0% to 6.5%.

[0033] The hot rolling adopts lubrication rolling, the hot rolling temperature is controlled at 1050℃~1150℃, multiple passes of small deformation rolling are carried out within this temperature range, the reduction of each pass is controlled at 10%~25%, and the total hot rolling reduction rate is controlled at 50%~90%.

[0034] In the three warm rolling passes, the temperature of the first warm rolling is 700°C to 600°C. In the three warm rolling passes, the temperature of the second warm rolling is 600°C to 500°C. In the three warm rolling passes, the temperature of the third warm rolling is 500°C to 400°C. The reduction ratio of each warm rolling pass in the three warm rolling passes is controlled to be 40% to 70%.

[0035] The intermediate annealing temperature is 800° C. to 850° C., and the texture of the finished plate is mainly cubic texture.

[0036] The present invention also provides a dual-oriented high silicon steel based on a rolling method combined with surface energy annealing, which is prepared by the preparation method. The chemical composition of the dual-oriented high silicon steel is as follows: Si: 6.3-6.5wt%, Mn: 0.05-0.8wt%, P: 0.005-0.009wt%, C: < 0.01wt%, S: < 0.01wt%, and the rest is Fe and unavoidable impurities. The dual-oriented high silicon steel P 2 / 1000 Between 0.47W / kg and 0.84W / kg, P 10 / 400 Between 3.16W / kg and 4.21W / kg.

[0037] The basic principles of the present invention are as follows:

[0038] (1) Hot rolling: Based on the academic idea that {100} oriented grains are stable under plane strain compression and are not easily recrystallized, the {100} texture is retained by avoiding hot rolling shear deformation. Low-temperature lubrication rolling can be used. Low-temperature lubrication rolling weakens the shear texture of the surface and subsurface layers of the hot-rolled plate, enhances the deformed near-cubic texture component, weakens the Goss component, and prevents abnormal growth of Goss during subsequent high-temperature annealing.

[0039] (2) Warm rolling: Three small deformation warm rollings combined with two intermediate annealings are used to weaken the {111} <112> Texture control increases the proportion of the cubic component, while also achieving "gradual plasticization," promoting the transition from order to disorder in high-silicon steel and preventing cracking during deformation. The concept of texture control is related to the deformation and recrystallization characteristics of cubic-oriented grains. Cubic-oriented grains are typically axisymmetric. After rolling with small deformations, the cubic orientation does not rotate excessively. Subsequent intermediate recovery annealing allows the cubic grains to undergo dynamic recovery, thereby increasing the cubic texture component.

[0040] (3) Intermediate annealing: The intermediate annealing temperature should not be too high and should be matched with the holding time. This is to inhibit the dynamic recrystallization of the warm rolled plate, uniformize the warm rolled plate structure and its morphological characteristics, and thus optimize the recrystallization texture of the finished product after annealing. The intermediate annealing process improves the plastic deformation ability of the high silicon steel plate on the one hand, and regulates the texture on the other hand. Generally, γ-ray grains have higher deformation storage energy and are more likely to recrystallize at the grain boundaries during the subsequent annealing process, forming new γ-oriented grains. The γ-ray texture is weakened by intermediate annealing, and the lower γ grain boundary density cannot provide more nucleation sites for the formation of new γ grains, thereby increasing the cubic texture component.

[0041] (4) High-temperature annealing: High-temperature annealing is performed in a pure hydrogen atmosphere. The combination of annealing temperature and time, on the one hand, improves the favorable orientation environment and thermodynamic conditions for the secondary recrystallization of cubic-oriented grains, and on the other hand, regulates the grain size and microstructure uniformity, thereby producing high-performance dual-oriented high-silicon steel. The annealing heating rate needs to be increased rapidly, i.e., 50℃~100℃ / min, to control the size of the primary recrystallized grains and avoid the abnormal secondary recrystallization of cubic-oriented grains.

[0042] The chemical composition of the high silicon steel applicable to the manufacturing method of the present invention is as follows by mass percentage: Si: 6.3-6.5wt%, Mn: 0.05-0.8wt%, P: 0.005-0.009wt%, C: < 0.01wt%, S: < 0.01wt%, and the remainder is Fe and unavoidable impurities.

[0043] The reasons for the ingredient restrictions are as follows:

[0044] Si: The Si mass percentage range is 6.3~6.5wt%. Si increases the resistivity and reduces eddy current.

[0045] On the other hand, if the silicon content exceeds 6.5wt%, the coercive force increases, the saturation magnetic induction intensity and the maximum magnetic permeability decrease, and the processability deteriorates significantly.

[0046] Mn: The range of Mn mass percentage is 0.05~0.8wt%. Mn is an essential element for improving hot rolling performance. The improvement effect is insufficient when the content is less than 0.05wt%.

[0047] P: The P content ranges from 0.005 to 0.009 wt%. P is an essential element for improving punching workability. A content below 0.005 wt% will not achieve the desired effect, while a content exceeding 0.1 wt% will deteriorate cold workability.

[0048] C: The range of C mass percentage is <0.01wt%. C is an element that is harmful to magnetic properties.

[0049] 0.01wt%, decarburization annealing is required and the decarburization time is too long, which reduces production efficiency.

[0050] S: The mass percentage of S is within the range of <0.01wt%. S is a forming element of non-metallic phases such as MnS, which are detrimental to magnetic properties. Its content should be less than 0.01wt%.

[0051] Example 1

[0052] (1) Raw material preparation: The silicon content of the square steel ingot is 6.5% and the thickness is 20 mm. The steel ingot is placed in a heating furnace and heated to 1150 °C.

[0053] (2) Hot rolling: The hot rolling starting temperature is 1150℃, the final rolling temperature is 900℃, lubrication rolling is used, the final slab is rolled to 2mm, and the total hot rolling reduction is 80%;

[0054] (3) Warm rolling: the first warm rolling temperature is 700℃, the final rolling temperature is 600℃, and the thickness is 2mm and 0.8mm respectively;

[0055] The secondary warm rolling starts at 600°C, the final rolling temperature is 500°C, and the thickness is 0.8mm to 0.4mm.

[0056] The three-stage warm rolling process starts at 500°C, finishes at 400°C, and is performed from 0.4mm to 0.2mm.

[0057] (4) Intermediate annealing: 850℃ for 30min, air cooling;

[0058] (5) Final annealing: anneal the warm-rolled sheet at 1150°C in a pure hydrogen atmosphere at a heating rate of 100°C / min.

[0059] Example 2

[0060] (1) Raw material preparation: The silicon content of the square steel ingot is 6.5% and the thickness is 20 mm. The steel ingot is placed in a heating furnace and heated to 1100 °C.

[0061] (2) Hot rolling: The hot rolling starting temperature is 1100℃, the final rolling temperature is 870℃, lubrication rolling is used, the final slab is rolled to 2mm, and the total hot rolling reduction is 80%;

[0062] (3) Warm rolling: the first warm rolling temperature is 700℃, the final rolling temperature is 600℃, and the thickness is 2mm and 0.8mm respectively;

[0063] The secondary warm rolling starts at 600°C, the final rolling temperature is 500°C, and the thickness is 0.8mm to 0.4mm.

[0064] The three-stage warm rolling process starts at 500°C, finishes at 400°C, and is performed from 0.4mm to 0.2mm.

[0065] (4) Intermediate annealing: 850℃ for 30min, air cooling;

[0066] (5) Final annealing: anneal the warm rolled sheet at 1150°C in a pure hydrogen atmosphere at a heating rate of 100°C / min.

[0067] Example 3

[0068] (1) Raw material preparation: The silicon content of the square steel ingot is 6.5% and the thickness is 20 mm. The steel ingot is placed in a heating furnace and heated to 1050 °C.

[0069] (2) Hot rolling: The hot rolling starting temperature is 1050℃, the final rolling temperature is 800℃, lubrication rolling is used, the final slab is rolled to 2mm, and the total hot rolling reduction is 60%;

[0070] (3) Warm rolling: the first warm rolling temperature is 700℃, the final rolling temperature is 600℃, and the thickness is 2mm and 0.8mm respectively;

[0071] The secondary warm rolling starts at 600°C, the final rolling temperature is 500°C, and the thickness is 0.8mm to 0.4mm.

[0072] The three-stage warm rolling process starts at 500°C, finishes at 400°C, and is performed from 0.4mm to 0.2mm.

[0073] (4) Intermediate annealing: 850℃ for 30min, air cooling;

[0074] (5) Final annealing: anneal the warm-rolled sheet at 1150°C in a pure hydrogen atmosphere at a heating rate of 100°C / min.

[0075] Among them, the above examples 1, 2, and 3 mainly study the effect of hot rolling temperature on weakening shear texture and improving {100} texture under the same hot rolling reduction rate. As the hot rolling temperature decreases, the degree of dynamic recrystallization of the surface and subsurface layers decreases significantly, the Goss shear texture is significantly weakened, and the proportion of λ texture (001∥ND) increases significantly. When the hot rolling temperature is 1050℃, the texture of the center layer of the hot rolled plate is mainly {100} <031> , {100} <021> The main texture is Goss shear texture, and there is a small amount of Goss shear texture in the subsurface. When the hot rolling temperature is 1100℃, {114} <481> The steel is significantly enhanced, and there are more brass textures in the subsurface. As the hot rolling temperature is further reduced, the texture is mainly {100} <011> ,{112} <110> The grain rotation law is as follows: In the center layer, under plane strain compression, for the initial rotated cubic orientation grains: {100} <011> Around <110> Axis steering {112} <110> ; For initial cubic oriented grains: {100} <001> Turn to {100} first <021> , then turned to {114} <481> The degree of orientation rotation is mainly affected by the hot rolling temperature.

[0076] Comparative Example 1

[0077] (1) Raw material preparation: The silicon content of the square steel ingot is 6.5% and the thickness is 5 mm. The steel ingot is placed in a heating furnace and heated to 1050 °C.

[0078] (2) Hot rolling: The hot rolling starting temperature is 1050℃, the final rolling temperature is 800℃, the final slab is rolled to 2mm, and the total hot rolling reduction is 60%;

[0079] (3) Warm rolling: the first warm rolling temperature is 700℃, the final rolling temperature is 600℃, and the thickness is 2mm and 0.8mm respectively;

[0080] The secondary warm rolling starts at 600°C, the final rolling temperature is 500°C, and the thickness is 0.8mm to 0.4mm.

[0081] The three-stage warm rolling process starts at 500°C, finishes at 400°C, and is performed from 0.4mm to 0.2mm.

[0082] (4) Intermediate annealing: 850℃ for 30min, air cooling;

[0083] (5) Final annealing: anneal the warm-rolled sheet at 1150°C in a pure hydrogen atmosphere at a heating rate of 100°C / min.

[0084] Comparative Example 1 was compared with Example 3 to investigate the effect of hot rolling reduction on the hot rolling texture. From a microscopic perspective, the proportion of {100} < 20° oriented grains within the hot-rolled plate was greater when the hot rolling reduction was low (23.5%) than when the hot rolling reduction was high (18.2%). Furthermore, the proportion of shear texture-oriented regions, represented by Gauss, brass, and copper types, was significantly lower than when the hot rolling reduction was high (3.2%) than when the hot rolling reduction was high (8.6%). These regions were present in large quantities in the subsurface layer, indicating that low reduction can suppress the formation of subsurface shear texture and facilitate the retention of the {100} texture.

[0085] Example 4

[0086] (1) Raw material preparation: The silicon content of the square steel ingot is 6.5% and the thickness is 20 mm. The steel ingot is placed in a heating furnace and heated to 1050 °C.

[0087] (2) Hot rolling: The hot rolling starting temperature is 1050℃, the final rolling temperature is 800℃, lubrication rolling is used, the final slab is rolled to 2mm, and the total hot rolling reduction is 60%;

[0088] (3) Warm rolling: the first warm rolling temperature is 700℃, the final rolling temperature is 600℃, and the thickness is 2mm and 0.8mm respectively;

[0089] The secondary warm rolling starts at 700°C, the final rolling temperature is 700°C, and the thickness is 0.8mm to 0.4mm.

[0090] The three-stage warm rolling process starts at 700°C, finishes at 700°C, and is performed from 0.4mm to 0.2mm.

[0091] Intermediate annealing: 950℃ for 40min, oil cooling;

[0092] (4) Intermediate annealing: 850℃ for 30min, air cooling;

[0093] (5) Final annealing: anneal the warm-rolled sheet at 1150°C in a pure hydrogen atmosphere at a heating rate of 100°C / min.

[0094] Example 4 was compared with Example 3 to investigate the effect of warm rolling temperature on the texture and plasticity of the warm-rolled plate. Higher warm rolling temperatures resulted in better plasticity, reduced deformation energy storage, lower nucleation rates within shear bands, larger primary recrystallized grain size, and unsatisfied secondary recrystallization kinetics for cubically oriented grains, leading to abnormal secondary recrystallization structure and, in turn, impacted the texture and magnetic properties of the finished plate.

[0095] Example 5

[0096] (1) Raw material preparation: The silicon content of the square steel ingot is 6.5% and the thickness is 5 mm. The steel ingot is placed in a heating furnace and heated to 1050°C.

[0097] (2) Hot rolling: The hot rolling starting temperature is 1050℃, the final rolling temperature is 800℃, lubrication rolling is used, the final slab is rolled to 2mm, and the total hot rolling reduction is 60%;

[0098] (3) Warm rolling: the first warm rolling temperature is 700℃, the final rolling temperature is 600℃, and the thickness is 2mm and 0.8mm respectively;

[0099] The secondary warm rolling starts at 600°C, the final rolling temperature is 500°C, and the thickness is 0.8mm to 0.4mm.

[0100] The three-stage warm rolling process starts at 500°C, finishes at 400°C, and is performed from 0.4mm to 0.2mm.

[0101] (4) Intermediate annealing: 850℃ for 30min, air cooling;

[0102] (5) Final annealing: anneal the warm-rolled sheet at 1150°C in a pure hydrogen atmosphere at a heating rate of 50°C / min.

[0103] The magnetic properties of the finished plate of Example 5 are shown in Table 1 below. The microstructure of the dual-oriented high silicon steel after high temperature annealing is as follows: Figure 2 As shown, the 45°ODF diagram after high temperature annealing is as follows Figure 3 As shown, the grain orientation imaging diagram after high temperature annealing is as follows Figure 4 As shown in Examples 1-5 and Comparative Example 1, a combination of low-reduction hot rolling (60%) and low-temperature lubrication rolling (1050°C) followed by three warm rolling cycles and two intermediate anneals weakens the γ texture and enhances the {100} texture. During the high-temperature annealing (1150°C), rapid heating suppresses the size of the primary recrystallized grains, creating a favorable thermodynamic and orientational environment for secondary recrystallization in the cubic orientation. The cubic-oriented grains, leveraging the low surface energy of the {100} orientation, undergo secondary recrystallization, ultimately producing a bi-oriented high-silicon steel strip with a predominantly cubic texture and excellent magnetic properties.

[0104] Table 1

[0105]

[0106] This invention uses silicon steel ingots containing 6.0% to 6.5% Si, with the balance being Fe and unavoidable impurities. The steel undergoes hot rolling, followed by three warm rolling steps and two intermediate annealing steps to enhance the cubic texture. After high-temperature annealing, the low surface energy of the {100} orientation is exploited to induce secondary recrystallization of the cubic grains. This results in a dual-oriented high-silicon steel with excellent magnetic properties in both the rolling and transverse directions. This dual-oriented high-silicon steel sheet has a wide range of applications, including as cores for electrical equipment such as motors, generators, small transformers, voltage stabilizers, and inductors.

[0107] The above is a detailed introduction to a dual-oriented high-silicon steel based on a rolling method combined with surface energy annealing and its preparation method provided in the embodiments of this application. The description of the above embodiments is only intended to help understand the method and core concept of this application; at the same time, for those skilled in the art, based on the concept of this application, there may be changes in the specific implementation method and application scope. In summary, the content of this specification should not be understood as limiting this application.

[0108] For example, certain words are used in the specification and claims to refer to specific components. Those skilled in the art should understand that hardware manufacturers may use different nouns to refer to the same component. This specification and claims do not use differences in names as a way to distinguish components, but use differences in the functions of components as the criteria for distinction. For example, "including" and "comprising" mentioned throughout the specification and claims are open-ended terms, so they should be interpreted as "including / including but not limited to". "Approximately" means that within an acceptable error range, those skilled in the art can solve the technical problems within a certain error range and basically achieve the technical effects. The subsequent description in the specification is a preferred embodiment of the present application, but the description is for the purpose of illustrating the general principles of the present application, and is not used to limit the scope of the present application. The scope of protection of the present application shall be as defined in the attached claims.

[0109] It should also be noted that the terms "include," "comprises," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a product or system comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such product or system. In the absence of further limitations, an element defined by the phrase "comprises a..." does not exclude the presence of other identical elements in the product or system comprising the element.

[0110] It should be understood that the term "and / or" as used herein is merely a description of the relationship between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0111] The above description shows and describes several preferred embodiments of the present application. However, as previously mentioned, it should be understood that the present application is not limited to the form disclosed herein and should not be construed as excluding other embodiments. Instead, the present application can be used in various other combinations, modifications, and environments and can be modified within the scope of the application concept described herein through the above teachings or technology or knowledge in the relevant field. Modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present application should be protected by the claims appended hereto.

Claims

1. A method for preparing dual-oriented high silicon steel based on rolling combined with surface energy annealing, characterized in that: The preparation method prepares a bi-oriented high silicon steel thin strip by sequentially performing hot rolling, pickling, three warm rollings, two intermediate annealings and final annealing on a silicon-containing square ingot; Among them, three warm rolling steps combined with two intermediate annealing steps are used to increase the percentage of cubic texture; The final annealing utilizes the low surface energy of {100} to induce abnormal growth of cubic oriented grains, and the finished product is a dual-oriented high-silicon steel with a sharp cubic texture. The silicon content in the silicon-containing ingot is 6.0% to 6.5%; The hot rolling adopts lubrication rolling, the hot rolling temperature is controlled at 1050℃~1150℃, and multiple passes of small deformation rolling are carried out within this temperature range, the reduction of each pass is controlled at 10%~25%, and the total reduction rate of hot rolling is controlled at 50%~90%; In the three warm rolling processes, the temperature of the first warm rolling process is 700°C to 600°C; In the three warm rolling processes, the temperature of the second warm rolling process is 600°C to 500°C; In the three warm rolling processes, the temperature of the third warm rolling process is 500° C. to 400° C. The reduction rate of each warm rolling in the three warm rolling passes is controlled at 40% to 70%.

2. The preparation method according to claim 1, characterized in that The intermediate annealing temperature is 800° C. to 850° C., and the texture of the finished plate is mainly cubic texture.

3. A dual-oriented high silicon steel based on rolling combined with surface energy annealing, prepared by the preparation method according to any one of claims 1-2, characterized in that: The chemical composition of the dual-oriented high-silicon steel is as follows: Si: 6.3-6.5wt%, Mn: 0.05-0.8wt%, P: 0.005-0.009wt%, C: < 0.01wt%, S: < 0.01wt%, and the rest is Fe and unavoidable impurities.

4. The dual-oriented high silicon steel according to claim 3, characterized in that: The core loss of the dual-oriented high silicon steel P 2 / 1000 Between 0.47W / kg and 0.84W / kg, P 10 / 400 Between 3.16W / kg and 4.21W / kg.

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