A method for evaluating cold-rolling workability of high-silicon non-oriented silicon steel, and a production method of high-silicon non-oriented silicon steel

Abstract

The application provides a method for evaluating the cold-rolling workability of high-silicon non-oriented silicon steel and a production method of high-silicon non-oriented silicon steel. The evaluation method is as follows: after normalizing, rectangular tensile samples are taken from the edge and middle of the steel coil along the plate width; the samples are processed into samples with a width of b and a length of l0; the edge and middle rectangular tensile samples are respectively placed on a material tensile testing machine for tensile testing until the samples are broken, and the actual length of the samples when broken is recorded as l 边 and l 中 , and i=(l 边 -l0) / (l 中 -l0)×100% is calculated; the cold-rolling workability of the high-silicon non-oriented silicon steel is evaluated according to the calculated i value. When i is greater than or equal to 75%, the high-silicon non-oriented silicon steel can be smoothly produced by cold rolling; when 75%>i≥60%, the cold-rolling process needs to be optimized and the auxiliary cold-rolling process is used; when i is less than 60%, the cold-rolling production cannot be directly and smoothly completed, and the edge needs to be trimmed.

Description

Technical Field

[0001] This invention belongs to the field of grain-oriented electrical steel production and manufacturing, and particularly relates to a method for evaluating the cold-rolling rollability of high-silicon non-oriented silicon steel and a method for producing high-silicon non-oriented silicon steel guided by the rollability evaluation. Background Technology

[0002] High-silicon non-oriented silicon steel typically contains 2% to 4% silicon and is an important soft magnetic material for manufacturing high-efficiency variable frequency compressors, drive motors for new energy vehicles, and servo motors. Due to its high silicon content and coarse grain structure, silicon steel exhibits higher deformation resistance but lower plasticity and toughness. This makes it prone to edge cracking and breakage during cold rolling, leading to an increase in abnormal silicon steel production and a lower product yield. Figure 1 This image shows the distribution of edge cracks in high-silicon non-oriented silicon steel after cold rolling. The edge quality of high-silicon non-oriented silicon steel strip is a significant factor leading to edge cracks and even strip breakage during cold rolling. Defects at the edge of hot-rolled raw materials and the quality of the disc shearing during the normalizing process can result in microcracks at the edge of the steel coil. These microcracks cannot be welded at high temperatures during the normalizing process. During cold rolling, the strip edge is subjected to uniaxial tensile stress, causing these microcracks to rapidly propagate and eventually fracture. To ensure the smooth operation of the cold rolling process for high-silicon non-oriented silicon steel and improve its efficiency, it is necessary to establish a method for accurately assessing the feasibility of cold rolling high-silicon non-oriented silicon steel.

[0003] A document published on December 3, 2021, with publication number CN113740144 A, discloses a method for evaluating the rollability of thin sheet electrical steel. The steps include placing a bending test sample with an acute angle between its two ends along its length between two parallel, moving plates and applying pressure, observing whether defects appear in the bent area of ​​the sample; if no defects appear, replacing it with another sample, adding an unbent sample within the bending arc, with the sample's thickness section in contact with the bending arc, placing it between the two plates and applying pressure, repeating the operation until cracks appear, and recording the number of unbent samples to assess the rollability of the thin sheet electrical steel. This invention can evaluate the cold rolling feasibility of electrical steel with a uniform microstructure throughout the coil using a bending method, but it cannot accurately evaluate the rollability of cold-rolled strip coils with edge cracks.

[0004] A document published on March 11, 2015, with publication number CN104399749A, discloses a cold rolling method to prevent edge cracking and brittle fracture of silicon steel with Si ≥ 3.5%. This invention preheats the steel sheet, uses emulsion spraying, and performs a single-pass cold rolling process, combined with low-tension coiling at the initial stage of coiling. This method can prevent edge cracking during the cold rolling process of silicon steel with Si ≥ 3.5%, and reduce brittle fracture and scrap rates. This invention effectively reduces the risk of strip breakage during the cold rolling of high-silicon non-oriented silicon steel by adjusting the production process. However, it does not address the evaluation of the rollability of high-silicon non-oriented silicon steel during cold rolling. Summary of the Invention

[0005] The purpose of this invention is to provide a method for evaluating the cold-rolling rollability of high-silicon non-oriented silicon steel. Addressing the problem that edge cracking and strip breakage are prone to occur during the cold rolling process of high-silicon non-oriented silicon steel, leading to an increase in abnormal materials and a decrease in product yield, this invention samples, tests, and classifies the non-oriented silicon steel before cold rolling to determine the impact of the steel coil edge quality on the smoothness of the cold rolling process. This allows for a graded evaluation of the cold-rolling rollability of high-silicon non-oriented silicon steel. By combining this method with appropriate production processes, the production efficiency of the silicon steel cold rolling process can be effectively improved.

[0006] This invention also provides a method for producing high-silicon non-oriented silicon steel. After evaluation using the above methods, the subsequent cold rolling process is determined based on the evaluation results for smooth production.

[0007] The specific technical solution of this invention is as follows:

[0008] A method for evaluating the cold-rollable properties of high-silicon non-oriented silicon steel includes the following steps:

[0009] 1) Take rectangular tensile specimens from the edge and middle of the normalized steel coil; process the rectangular tensile specimens into edge rectangular tensile specimens and middle rectangular tensile specimens with a width of b and a length of l0 respectively.

[0010] 2) Perform tensile tests on the edge rectangular tensile specimen and the middle rectangular tensile specimen respectively, and record the actual length l of the edge rectangular tensile specimen when it breaks. 边 The actual length l of the rectangular tensile specimen at break in the middle 中 Calculate the elongation ratio i = (l) of the rectangular tensile specimen at the edge and the rectangular tensile specimen at the center. 边 -l0) / (l 中 -l0)×100%;

[0011] 3) The cold rollability of high-silicon non-oriented silicon steel is evaluated based on the calculated i value.

[0012] The rectangular tensile specimen mentioned in step 1) refers to a specimen that is rectangular and used for subsequent tensile tests, hence the name rectangular tensile specimen; the rectangular tensile specimen taken from the edge is processed into an edge rectangular tensile specimen with a set length and width; the rectangular tensile specimen taken from the middle of the steel strip is processed into a middle rectangular tensile specimen with a set length and width.

[0013] In step 1), the rectangular tensile specimen taken along the edge of the steel strip is a rolling rectangular tensile specimen taken along the edge of the steel strip, that is, it is cut along the outermost part of the width direction of the steel strip. The long side of the rectangular tensile specimen is along the rolling direction of the steel strip, and one of the long sides is the edge of the steel strip.

[0014] In step 1), taking a rectangular tensile specimen from the middle of the steel strip means cutting it within ±300mm of the center of the steel strip along the rolling direction, with the long side of the rectangular tensile specimen along the rolling direction of the steel strip.

[0015] The sampling locations of the edge rectangular tensile specimen and the middle rectangular tensile specimen are shown in the schematic diagram below. Figure 2 As shown;

[0016] In step 1), the dimensions of the edge rectangular tensile specimen and the middle rectangular tensile specimen after sampling and processing are consistent, with a width b of 8 to 30 mm and a length l0 of (8 to 20) × b, where b is in mm and l0 is in mm. The longitudinal l0 deviation of different tensile specimens is controlled within ±0.5 mm, and the width b deviation is controlled within ±0.2 mm.

[0017] In step 1), the processing specifically includes:

[0018] The four edges of the central rectangular tensile specimen are machined along the thickness direction to obtain a central rectangular tensile specimen of a set size; the machining roughness Ra is ensured to be below 1.5 μm; the shearing edge is machined using a medium-speed wire EDM machine or a milling machine.

[0019] For the edge rectangular tensile specimen, the other long side is machined based on the long side of the actual edge of the steel strip, and the two short sides are also machined to obtain the edge rectangular tensile specimen of the set size; the machining roughness Ra is guaranteed to be below 1.5μm; that is, the long side of the actual edge of the steel strip of the edge rectangular tensile specimen is not machined, and the other three sides are machined along the thickness direction to ensure that the machining roughness Ra is below 1.5μm; the shearing edge is machined using a medium-speed wire EDM machine or a milling machine.

[0020] In step 2), the rectangular tensile specimens at the edges and the rectangular tensile specimens at the center are placed on a material tensile testing machine for tensile testing until the specimens break.

[0021] In step 2), the clamping area of ​​the tensile testing machine is within 25mm to 40mm from both ends of the rectangular tensile specimens at the edges and the middle rectangular tensile specimens along the long side. A schematic diagram of the specimen processing is shown below. Figure 3 As shown;

[0022] In step 2), l 边 l is the actual length of the rectangular tensile specimen at the edge when it breaks. 中 The actual length of the tensile specimen at break in the middle section; l 边 and l 中 The unit is mm.

[0023] In step 3), when i ≥ 75%, high-silicon non-oriented silicon steel can be successfully cold-rolled.

[0024] When 75% > i ≥ 60%, high-silicon non-oriented silicon steel needs to be produced by cold rolling process with the assistance of steel coil heating, roll gap lubrication and other processes.

[0025] When i < 60%, high-silicon non-oriented silicon steel cannot be directly and smoothly produced by cold rolling. The steel strip needs to be re-trimmed to remove edge defects. After evaluation, cold rolling can be carried out after i ≥ 75%.

[0026] This invention provides a method for producing high-silicon non-oriented silicon steel. After evaluating the cold-rolling rollability of the high-silicon non-oriented silicon steel using the aforementioned method, the production method is determined based on the evaluation results. Specifically:

[0027] The production method of the high-silicon non-oriented silicon steel is as follows: molten steel is continuously cast, hot rolled, normalized, pickled, and the steel coils after pickling are sampled to evaluate their cold rolling rollability, the cold rolling process is determined, and recrystallization annealing is performed to produce the high-silicon non-oriented silicon steel finished product.

[0028] The high-silicon non-oriented silicon steel contains the following components by weight percentage: Si: 2.5%–4.50%; Als: 0.10%–1.0%; Si+Als≥3.5%; Mn: 0.1%–0.4%; C, S, N, Ti and O are all less than 0.003%; the balance is Fe and unavoidable impurities.

[0029] Si and Als are alloying elements in non-oriented silicon steel. As the total content increases, the resistivity of silicon steel increases and the iron loss decreases. However, as the content of Si and Als increases, the material strength increases and the plasticity and toughness decrease. During cold rolling, rolling defects or even strip breakage risks may occur.

[0030] Mn: It belongs to the alloying elements of electrical steel. Within a certain range, Mn can increase the proportion of favorable texture in the microstructure, improve the magnetism, and at the same time improve the ductility of high silicon electrical steel.

[0031] C, S, N, O and Ti: All four elements are harmful elements in silicon steel. An increase in their content leads to an increase in the content of non-metallic inclusions in non-oriented silicon steel and a significant increase in iron loss. In principle, the lower the content of harmful elements, the better.

[0032] The molten steel is continuously cast into a billet of 200-280 mm;

[0033] The hot rolling process specifically involves heating continuously cast slabs to 1000–1180°C and rolling them into hot-rolled coils with a thickness of 1.5 mm–2.5 mm through 4 passes of rough rolling and 7 passes of finish rolling.

[0034] Normalization: Hot-rolled coils are normalized at 850℃~950℃ for 2min~4min. For finished products with high dimensional requirements, the edges are trimmed by a disc shear before normalization, with a trimming width of 5~20mm.

[0035] After normalization, the steel coils are pickled and evaluated according to the method described above for assessing the cold rolling suitability of high-silicon non-oriented silicon steel. Based on the evaluation results, the cold rolling process is determined as follows: When i ≥ 75%, high-silicon non-oriented silicon steel can be successfully cold rolled; it is cold rolled to a thickness of 0.25 mm to 0.60 mm in one pass using a six-roll single-stand mill, and then recrystallized and annealed at 880℃ to 980℃ to form the finished high-silicon non-oriented silicon steel product; when 75% > i ≥ 60%, high-silicon non-oriented silicon steel needs to be optimized through cold rolling process optimization to assist in the cold rolling process; when i < 60%, high-silicon non-oriented silicon steel cannot be directly and successfully cold rolled, and the edges need to be trimmed.

[0036] Preferably, high-silicon non-oriented silicon steel with i≥75% can be cold-rolled to a thickness of 0.25mm~0.60mm in one pass using a six-roll single-stand rolling mill, and then recrystallized and annealed at 880℃~980℃ to form a finished high-silicon non-oriented silicon steel product; high-silicon non-oriented silicon steel with i<75% can be cold-rolled to a thickness of 0.25mm~0.60mm in one pass using a six-roll single-stand rolling mill after process optimization and edge trimming, and then recrystallized and annealed at 880℃~980℃ to form a finished high-silicon non-oriented silicon steel product.

[0037] High-silicon non-oriented silicon steel, due to its high content of alloying elements such as Si and Al, has low plasticity and is prone to edge defects and strip breakage during cold rolling, affecting the production of the cold rolling process. Among these defects, edge defects of the strip are one of the important factors leading to edge cracks and even strip breakage during the cold rolling process. Edge defects of the steel coil and the quality of the disc shearing edge in the normalizing process can lead to microcracks at the edge of the steel coil. These microcracks cannot be welded at high temperature during the normalizing process. During the cold rolling process, the strip edge is subjected to uniaxial tensile stress, and the microcracks rapidly expand to form cracks and eventually break.

[0038] Compared with existing technologies, the method for evaluating the rolling feasibility of cold rolling of high-silicon non-oriented silicon steel provided by this invention, through stretching rectangular samples at the center and edges of the plate in the width direction and combining theoretical calculations, classifies the cold rolling rollability of normalized high-silicon non-oriented silicon steel coils. Based on different evaluation results, different subsequent cold rolling processes are determined, providing important support for the smooth and efficient production of the cold rolling process. Moreover, the method of this invention is simple and easy to operate, which is of great significance for the smooth operation of the cold rolling process of high-silicon non-oriented silicon steel and the improvement of production efficiency. Attached Figure Description

[0039] Figure 1 The crack is located at the edge of a cold-rolled high-silicon non-oriented silicon steel.

[0040] Figure 2 This is a schematic diagram of the sampling location in this invention;

[0041] Figure 3 This is a schematic diagram of the tensile specimen of the present invention;

[0042] Figure 4 This refers to the edge quality during the cold rolling process of high-silicon non-oriented silicon steel in Example 1.

[0043] Figure 5 The distribution of edge cracks during the cold rolling process of high-silicon non-oriented silicon steel in Example 2;

[0044] Figure 6 Example 3 shows the strip breakage during the cold rolling process of high-silicon non-oriented silicon steel. Detailed Implementation

[0045] The specific embodiments of the present invention will be further described in detail through the following examples.

[0046] Example 1

[0047] A method for producing high-silicon non-oriented silicon steel involves evaluating the cold-rolling rollability of the high-silicon non-oriented silicon steel using the method of this invention, and then determining the production method based on the evaluation results. Specifically, the method comprises:

[0048] 1) The molten steel after vacuum smelting was continuously cast into a slab with a thickness of 230 mm. The chemical composition of the slab by weight percentage was as follows: Si: 3.15%; Als: 0.46%; Si+Als: 3.61%; Mn: 0.15%; C: 0.0017%; S: 0.0009%; N: 0.0011%; Ti: 0.0022%; O: 0.0005%; with the remainder being Fe and unavoidable impurity elements.

[0049] 2) The slab is heated in a walking beam furnace to a process temperature of 1140℃ and a soaking time of 200min. It is then rolled into a hot-rolled coil with a thickness of 2.2mm through 4 passes of rough rolling and 7 passes of finish rolling.

[0050] 3) The hot-rolled coils mentioned above are normalized at 905℃ for 2.5 minutes. Before normalization, the edges are trimmed by a disc shear with a trimming width of 10 mm.

[0051] 4) After normalizing, the steel coils are pickled, and rectangular tensile samples are taken from both the edge and center of the steel strip. The rectangular tensile samples taken from the edge of the steel strip are taken along the rolling direction, i.e., cut along the outermost edge of the steel strip width, with the long side of the sample aligned with the rolling direction of the steel strip; one long side is the edge of the steel strip. The rectangular tensile samples taken from the center of the steel strip are cut within ±300mm of the center along the rolling direction, with the long side of the sample aligned with the rolling direction of the steel strip. After sampling, processing is performed: for the central rectangular tensile test... The four edges of the sample are machined along the thickness direction to obtain a central rectangular tensile specimen of a set size. For the edge rectangular tensile specimen, the other long side is machined based on the long side of the actual edge of the steel strip, and the two short sides are also machined to obtain an edge rectangular tensile specimen of a set size. The edge rectangular tensile specimen and the central rectangular tensile specimen are obtained. The shearing edge is machined using a medium-speed wire EDM machine with a surface roughness Ra of 0.8 μm. The width b of the machined specimen is 25 mm and the length l0 is 300 mm.

[0052] 5) The rectangular tensile specimens at the edges and the rectangular tensile specimens at the center were placed on a material tensile testing machine for tensile testing. The clamping area of ​​the tensile testing machine was within 25mm to 40mm from both ends along the long side. The actual length of the specimen at the point of breakage was recorded as l. 边 346mm, l 中 It is 358mm, according to the formula i=(l 边 -l0) / (l 中 -l0)×100%, where i is 79.31%; when i≥75%, high silicon non-oriented silicon steel can be successfully cold-rolled.

[0053] 6) After normalizing, the steel coils that have been shot-peened and pickled are cold rolled to the target thickness of 0.30mm in 6 passes using a six-roll single-stand rolling mill, and then recrystallized and annealed at 880℃ to form high-silicon non-oriented silicon steel finished products.

[0054] Example 2 (as a comparison)

[0055] A method for producing high-silicon non-oriented silicon steel, specifically:

[0056] 1) The molten steel after vacuum smelting was continuously cast into a slab with a thickness of 230 mm. The chemical composition of the slab by weight percentage was as follows: Si: 3.17%; Als: 0.47%; Si+Als: 3.64%; Mn: 0.18%; C: 0.0022%; S: 0.0007%; N: 0.0013%; Ti: 0.0019%; O: 0.0007%; with the remainder being Fe and unavoidable impurity elements.

[0057] 2) The slab is heated in a walking beam furnace to a process temperature of 1140℃ and a soaking time of 200min. It is then rolled into a hot-rolled coil with a thickness of 2.2mm through 4 passes of rough rolling and 7 passes of finish rolling.

[0058] 3) The hot-rolled coils mentioned above are normalized at 905℃ for 2.5 minutes. Before normalization, the edges are trimmed by a disc shear with a trimming width of 10 mm.

[0059] 4) After normalization, the steel coil is pickled, and then rectangular tensile specimens are taken from the edge and middle of the steel strip respectively. The specimens are processed in the same way as in Example 1 to obtain tensile specimens with a width b of 25 mm and a length l0 of 300 mm.

[0060] 5) The rectangular tensile specimens at the edges and the rectangular tensile specimens at the center were placed on a material tensile testing machine for tensile testing, and the actual length of the specimens at the point of breakage was recorded as l. 边 333mm, l 中 It is 352mm, according to the formula i=(l 边 -l0) / (l 中 -l0), where i is calculated to be 63.46%;

[0061] 6) The normalized steel coils were rolled using a six-roll single-stand mill, and were planned to be cold rolled to a thickness of 0.30 mm in one pass in six passes. However, production was stopped when the third pass was rolled because a large number of cracks appeared on the edge of the steel coil.

[0062] Example 3 (as a comparison)

[0063] A method for producing high-silicon non-oriented silicon steel, specifically:

[0064] 1) The molten steel after vacuum smelting was continuously cast into a slab with a thickness of 230 mm. The chemical composition of the slab by weight percentage was as follows: Si: 3.14%; Als: 0.49%; Si+Als: 3.63%; Mn: 0.24%; C: 0.0019%; S: 0.0006%; N: 0.0008%; Ti: 0.0024%; O: 0.0006%; with the remainder being Fe and unavoidable impurity elements.

[0065] 2) The slab is heated in a walking beam furnace to a process temperature of 1140℃ and a soaking time of 190min. It is then rolled into a hot-rolled coil with a thickness of 2.2mm through 4 passes of rough rolling and 7 passes of finish rolling.

[0066] 3) The hot-rolled coils mentioned above are normalized at 905℃ for 2.5 minutes. Before normalization, the edges are trimmed by a disc shear with a trimming width of 10 mm.

[0067] 4) After normalization, the steel coil is pickled, and then rectangular tensile specimens are taken from the edge and middle of the steel strip respectively. The specimens are processed in the same way as in Example 1. The width b of the tensile specimen is 25 mm and the length l0 is 300 mm.

[0068] 5) Rectangular tensile specimens were placed on a material tensile testing machine for tensile testing, and the actual length of the specimen at the point of breakage was recorded as l. 边 320mm, l 中 It is 349mm, according to the formula i=(l 边 -l0) / (l 中 -l0), where i is calculated to be 40.82%;

[0069] 6) After normalization, the steel coil is planned to be cold rolled in six passes to the target thickness of 0.30mm. The strip breaks when the first pass of the steel coil reaches about 450 meters.

[0070] The method of this invention is used to evaluate the rollability of high-silicon non-oriented silicon steel after normalization and cold rolling. This allows for the classification and grading of the rolling feasibility of steel coils before cold rolling, effectively reducing the occurrence of edge cracking and strip breakage accidents in the cold rolling of high-silicon non-oriented silicon steel, and improving product yield and production efficiency.

Claims

1. A method for evaluating the cold-rollable properties of high-silicon non-oriented silicon steel, characterized in that, The method includes the following steps: 1) Take rectangular tensile specimens from the edge and middle of the normalized steel coil; process the rectangular tensile specimens into edge rectangular tensile specimens and middle rectangular tensile specimens with a width of b and a length of l0 respectively. 2) Perform tensile tests on the edge rectangular tensile specimen and the middle rectangular tensile specimen respectively, and record the actual length l of the edge rectangular tensile specimen when it breaks. 边 The actual length l of the rectangular tensile specimen at break in the middle 中 Calculate the elongation ratio i = (l) of the rectangular tensile specimen at the edge and the rectangular tensile specimen at the center. 边 -l0) / (l 中 -l0)×100%; 3) Evaluate the cold rollability of high-silicon non-oriented silicon steel based on the calculated i value; In step 3), when i ≥ 75%, high-silicon non-oriented silicon steel can be successfully cold-rolled. When 75% > i ≥ 60%, high-silicon non-oriented silicon steel needs to be produced by using steel coil heating and roll gap lubrication processes to assist the cold rolling process. When i < 60%, high-silicon non-oriented silicon steel cannot be directly and smoothly produced by cold rolling. The strip needs to be re-trimmed. After trimming, cold rolling can be carried out after i ≥ 75% is evaluated.

2. The method according to claim 1, characterized in that, In step 1), the rectangular tensile specimen taken along the edge of the steel strip is a rolling direction rectangular tensile specimen taken along the edge of the steel strip, where one long side is the edge of the steel strip; the rectangular tensile specimen taken in the middle of the steel strip means that it is cut along the rolling direction within ±300mm of the center of the steel strip, and the long side of the rectangular tensile specimen is along the rolling direction of the steel strip.

3. The method according to claim 1, characterized in that, In step 1), the width b is 8~30mm and the length l0 is (8~20)×b, where b is in mm and l0 is in mm.

4. The method according to claim 1, characterized in that, The processing described in step 1) is as follows: the four sides of the central rectangular tensile specimen are processed along the thickness direction to obtain a central rectangular tensile specimen of a set size; for the edge rectangular tensile specimen, the other long side is processed based on the long side of the actual edge of the steel strip, and the two short sides are also processed to obtain an edge rectangular tensile specimen of a set size.

5. A method for producing high-silicon non-oriented silicon steel, characterized in that, After evaluating the cold-rollability of high-silicon non-oriented silicon steel using the method described in any one of claims 1-4, the production method is determined based on the evaluation results. Specifically, the process involves continuous casting, hot rolling, normalizing, pickling, evaluating the cold-rollability of high-silicon non-oriented silicon steel, determining the cold rolling process, and recrystallization annealing to produce the finished high-silicon non-oriented silicon steel product.

6. The production method according to claim 5, characterized in that, The high-silicon non-oriented silicon steel contains the following components by weight percentage: Si: 2.5%~4.50%; Als: 0.10%~1.0%; Si+Als≥3.5%; Mn: 0.1%~0.4%; C, S, N, Ti and O are all less than 0.003%; the balance is Fe and unavoidable impurities.

7. The production method according to claim 5, characterized in that, The hot rolling process specifically involves heating continuously cast slabs to 1000~1180℃ and then rolling them into hot-rolled coils with a thickness of 1.5mm~2.5mm through rough rolling and finish rolling.

8. The production method according to claim 5, characterized in that, Normalization: 850℃~950℃, 2min~4min normalization treatment.

9. The production method according to claim 5, characterized in that, After normalization, when i ≥ 75%, high-silicon non-oriented silicon steel can be successfully cold-rolled to a thickness of 0.25 mm to 0.60 mm in one cold rolling process, and then recrystallized and annealed at 880℃ to 980℃ to form the finished high-silicon non-oriented silicon steel product. When 75% > i ≥ 60%, high-silicon non-oriented silicon steel needs to be produced by cold rolling process assisted by steel coil heating and roll gap lubrication. When i < 60%, high-silicon non-oriented silicon steel cannot be directly and successfully cold-rolled. The strip steel needs to be re-trimmed, and after trimming, cold rolling can be carried out after i ≥ 75%.

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