High-temperature annealing method of oriented silicon steel

Abstract

The invention provides a high-temperature annealing method of oriented silicon steel, and relates to the technical field of heat treatment of steel and iron materials, the method comprises the following steps: under the condition that a trolley is located at a first stage position in an annealing furnace, adjusting the volume ratios of nitrogen and hydrogen in the annealing furnace to be 50% respectively; the temperature in the annealing furnace is adjusted from low to high, and the temperature adjustment range is 700-1200 DEG C; under the condition that the trolley is located at the second-stage position in the annealing furnace, the volume ratio of hydrogen in the annealing furnace is adjusted to be 100%; the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 1200-660 DEG C; the trolley is sequentially located at the first stage position and the second stage position.

Description

Technical Field

[0001] The present invention relates to the technical field of heat treatment of steel materials, and in particular to a high-temperature annealing method for oriented silicon steel. Background Art

[0002] The dual-trolley continuous annealing process enables more precise atmosphere control. During the annealing process, as the dual trolleys operate continuously, the furnace atmosphere composition, concentration, and flow rate can be adjusted in real time according to the needs of different stages. In the early stages of annealing, a high-concentration reducing atmosphere is introduced to quickly remove the oxide layer on the surface of the silicon steel; in the later stages of annealing, the atmosphere composition is adjusted to promote the optimization of the silicon steel's crystal structure. In contrast, existing annealing processes struggle to achieve such precise atmosphere control. At the same time, the coordinated optimization of temperature control and atmosphere concentration is often overlooked, making it difficult to fully tap the performance potential of silicon steel, and creating bottlenecks in improving product qualification rates and magnetic properties.

[0003] Prior art, such as Chinese invention patent publication number CN2521566Y, discloses a single- or double-row tunnel-type, online, gas-shielded continuous annealing furnace. In the RP section, hot nitrogen is used to displace cold air from the hood to minimize oxygen and moisture content. Once the annealing train enters the heating tunnel, an online gas shielding system continuously replenishes nitrogen into each train, maintaining a slightly positive nitrogen pressure within each hood, achieving online gas shielding. The annealing train, intermittently pushed by a pusher, slowly moves forward in sequence. Within the heating tunnel, several pairs of upper and lower burners continuously heat the heat-resistant steel inner hood and the metal material therein, controlling the temperature according to process requirements through preheating, weak heating, strong heating, and uniform heating. However, the aforementioned reference document does not disclose the coordinated optimization of temperature control and atmosphere concentration. Summary of the Invention

[0004] In order to solve the technical problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a high-temperature annealing method for oriented silicon steel, which can perfectly cooperate with the existing temperature control by differentiating the atmosphere concentration in each section, and can significantly improve the product qualification rate and magnetic properties.

[0005] To achieve the above-mentioned object of the invention, the present invention provides a high-temperature annealing method for grain-oriented silicon steel, the method comprising: When the oriented silicon steel is located in the first stage of the annealing furnace, the volume ratio of nitrogen and hydrogen in the annealing furnace is adjusted to 50% each; and the temperature in the annealing furnace is adjusted from low to high, and the temperature adjustment range is 700° C. to 1200° C.; When the oriented silicon steel is located in the second stage of the annealing furnace, the volume ratio of hydrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 1200° C. to 660° C.; The oriented silicon steel is located successively at the first stage position and the second stage position.

[0006] According to a technical solution of the present invention, it also includes: When the oriented silicon steel is located at the zero stage in the annealing furnace, the volume ratio of nitrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from low to high, and the temperature adjustment range is 550° C. to 700° C.; The oriented silicon steel is located successively at the zeroth stage position and the first stage position.

[0007] According to a technical solution of the present invention, it also includes: When the oriented silicon steel is located in the third stage of the annealing furnace, the volume ratio of nitrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 570° C. to room temperature; The oriented silicon steel is located successively at the second stage position and the third stage position.

[0008] According to a technical solution of the present invention, the first stage position is parking space T3 to T16 in the annealing furnace; The parking space is where the trolley carrying the oriented silicon steel is located; When the oriented silicon steel is located at parking positions T3 to T7, adjust the temperature in the annealing furnace to 700℃±5℃; When the oriented silicon steel is located in the T8 position, adjust the temperature in the annealing furnace to 775℃±5℃; When the oriented silicon steel is located at the T9 position, adjust the temperature in the annealing furnace to 850℃±3℃; When the oriented silicon steel is located at the T10 position, adjust the temperature in the annealing furnace to 925℃±3℃; When the oriented silicon steel is located at the T11 parking position, adjust the temperature in the annealing furnace to 1000℃±3℃; When the oriented silicon steel is located at the T12 position, adjust the temperature in the annealing furnace to 1050℃±3℃; When the oriented silicon steel is located at the T13 position, adjust the temperature in the annealing furnace to 1100℃±3℃; When the oriented silicon steel is located in the T14 position, adjust the temperature in the annealing furnace to 1180℃±3℃; When the oriented silicon steel is located at parking positions T15~T16, adjust the temperature in the annealing furnace to 1200℃±3℃.

[0009] According to a technical solution of the present invention, the second stage position is the T17 to T28 parking spaces in the annealing furnace; When the oriented silicon steel is located at parking positions T17 to T20, adjust the temperature in the annealing furnace to 1200℃±3℃; When the oriented silicon steel is located at the T21 position, adjust the temperature in the annealing furnace to 1140℃±3℃; When the oriented silicon steel is located at the T22 position, adjust the temperature in the annealing furnace to 1080℃±3℃; When the oriented silicon steel is located at the T23 position, adjust the temperature in the annealing furnace to 1020℃±3℃; When the oriented silicon steel is located in the T24 position, adjust the temperature in the annealing furnace to 960℃±3℃; When the oriented silicon steel is located at the T25 position, adjust the temperature in the annealing furnace to 900℃±3℃; When the oriented silicon steel is located at the T26 position, adjust the temperature in the annealing furnace to 840℃±3℃; When the oriented silicon steel is located at position T27, adjust the temperature in the annealing furnace to 750℃±3℃; When the oriented silicon steel is located at the T28 position, the temperature in the annealing furnace is adjusted to 660℃±3℃.

[0010] According to a technical solution of the present invention, the zeroth stage position is the T1 parking space ~ T2 parking space in the annealing furnace; When the oriented silicon steel is located in the T1 parking space, adjust the temperature in the annealing furnace to 550℃±5℃; When the oriented silicon steel is located in the T2 parking position, adjust the temperature in the annealing furnace to 700℃±5℃.

[0011] According to a technical solution of the present invention, the third stage position is parking position T29 to parking position T31 in the annealing furnace; When the oriented silicon steel is located in the T29 position, adjust the temperature in the annealing furnace to 570℃±5℃; When the oriented silicon steel is located at parking positions T30 to T31, the temperature in the annealing furnace is adjusted to room temperature.

[0012] According to a technical solution of the present invention, When the oriented silicon steel is located at parking positions T1 to T2, adjust the furnace pressure in the annealing furnace to 300 Pa; When the oriented silicon steel is located at parking positions T3 to T31, the furnace pressure in the annealing furnace is adjusted to 200Pa.

[0013] According to a technical solution of the present invention, the operation time of the oriented silicon steel in each parking space T1 to T31 is 5 to 7 hours.

[0014] According to a technical solution of the present invention, when the oriented silicon steel is located in parking spaces T1 to T2, nitrogen with a volume of 20 cubic meters under standard atmospheric pressure is introduced; When the oriented silicon steel is located in parking spaces T3 to T9, nitrogen and hydrogen with a volume of 8 cubic meters each under standard atmospheric pressure are introduced; When the oriented silicon steel is located in parking spaces T10 to T16, nitrogen and hydrogen with a volume of 6 cubic meters each under standard atmospheric pressure are introduced; When the oriented silicon steel is located in parking spaces T17 to T22, 8 cubic meters of hydrogen gas is introduced at standard atmospheric pressure; When the oriented silicon steel is located in parking spaces T23 to T28, 12 cubic meters of hydrogen gas is introduced at standard atmospheric pressure; When the oriented silicon steel is located in parking spaces T29 to T31, 20 cubic meters of nitrogen gas at standard atmospheric pressure is introduced; The volume of the annealing furnace inner cover corresponding to each parking space is 9.1m 3 .

[0015] Compared with the prior art, the present invention has the following beneficial effects: This invention provides a high-temperature annealing method for grain-oriented silicon steel. Taking into account the characteristics of grain-oriented silicon steel, this method utilizes phased atmosphere control during continuous high-temperature annealing using a tunnel-type dual-carriage system to precisely control the microstructure and properties of the steel. The method also precisely determines the optimal nitrogen and hydrogen concentration ratio range for different annealing stages.

[0016] Precisely match temperature control and atmosphere concentration. The annealing process is divided into multiple stages, with different atmosphere concentrations set according to the temperature characteristics of each stage. During the annealing preheating stage, a lower atmosphere concentration is used to prevent premature overreaction on the silicon steel surface, while slowly increasing the temperature to lay a stable foundation for subsequent processes. Entering the core high-temperature annealing stage, the atmosphere concentration is increased to allow the silicon steel to fully complete key reactions such as recrystallization in a suitable atmosphere, promoting grain growth and texture optimization. During the cooling stage, the atmosphere concentration is adjusted again to prevent oxidation of the silicon steel surface and ensure its surface quality and magnetic properties.

[0017] By seamlessly integrating differentiated atmosphere concentrations within each section with existing temperature control, product qualification rates and magnetic properties can be significantly improved. Precise atmosphere concentration control reduces product defects caused by unsuitable atmospheres, improving product qualification rates. Furthermore, the optimized atmosphere creates favorable conditions for enhancing the magnetic properties of silicon steel, effectively improving its magnetic permeability and reducing iron losses, ultimately achieving even higher levels of product performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0019] Figure 1 A diagram schematically showing a parking area in a high-temperature annealing method for grain-oriented silicon steel according to an embodiment of the present invention; Figure 2 The flowchart schematically shows a high temperature annealing method for grain-oriented silicon steel according to one embodiment of the present invention. DETAILED DESCRIPTION

[0020] The description of the embodiments in this specification should be combined with the corresponding drawings, which should be considered a complete part of this specification. In the drawings, the shapes and thicknesses of the embodiments may be exaggerated and indicated for simplicity or convenience. Furthermore, the various structural components in the drawings will be described separately. It is worth noting that components not shown in the drawings or not described in words are known to those of ordinary skill in the art.

[0021] The description of the embodiments herein and any references to directions and orientations are for ease of description only and are not to be construed as limiting the scope of the present invention. The following description of the preferred embodiments may involve combinations of features, which may exist independently or in combination. The present invention is not specifically limited to the preferred embodiments. The scope of the present invention is defined by the claims.

[0022] like Figures 1 and 2 As shown, a high temperature annealing method for grain-oriented silicon steel of the present invention comprises: When the oriented silicon steel is located in the first stage of the annealing furnace, the volume ratio of nitrogen and hydrogen in the annealing furnace is adjusted to 50% each; and the temperature in the annealing furnace is adjusted from low to high, and the temperature adjustment range is 700℃~1200℃; When the oriented silicon steel is located in the second stage of the annealing furnace, the volume ratio of hydrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 1200℃~660℃; The oriented silicon steel is located in the first stage position and the second stage position successively.

[0023] In this embodiment, the oriented silicon steel semi-finished product is further processed by loading the oriented silicon steel semi-finished product coil on a trolley and processing it in a high-temperature annealing furnace according to the following stage procedures.

[0024] Specifically, when the trolley is in the first stage position, it is in the preheating and heating stage of high-temperature annealing of oriented silicon steel. By precisely adjusting the ratio of N2 and H2, the hydrogen concentration ratio is stabilized at 50%, ensuring that the silicon steel can be heated steadily according to the predetermined heating rate, avoiding abnormal heating or process interruption caused by inappropriate atmosphere, improving the stability and continuity of the annealing process, and thus improving the overall production efficiency.

[0025] When the trolley is in the second stage, the core stage of high-temperature annealing for grain-oriented silicon steel, the hydrogen concentration reaches 100%, creating an ideal atmosphere for recrystallization and grain growth. The pure H2 atmosphere promotes uniform grain growth and texture optimization, effectively reducing iron loss and increasing magnetic permeability, significantly enhancing the magnetic properties of grain-oriented silicon steel, meeting the high-magnetic silicon steel requirements of high-end electrical equipment.

[0026] This embodiment provides a more suitable environment for silicon steel annealing through precise atmosphere control, effectively reduces the generation of defects such as oxidation, and improves the product qualification rate and the stability of magnetic properties.

[0027] The high temperature annealing method for oriented silicon steel further comprises: When the oriented silicon steel is located at the zero stage in the annealing furnace, the volume ratio of nitrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from low to high, and the temperature adjustment range is 550℃~700℃; The oriented silicon steel is located at the zeroth stage position and the first stage position successively.

[0028] In this embodiment, the zeroth stage is the preheating stage, and N2 is used to purge and replace the air in the furnace to prevent oxidation, thereby avoiding contact between silicon steel and harmful gases such as oxygen during the annealing process, reducing the occurrence of defects such as surface oxidation and cracks, ensuring the surface quality of silicon steel, and improving the appearance quality and yield rate of the product.

[0029] The high temperature annealing method for oriented silicon steel further comprises: When the oriented silicon steel is located in the third stage of the annealing furnace, the volume ratio of nitrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 570°C to room temperature; Oriented silicon steel is located in the second stage and the third stage respectively.

[0030] In this embodiment, the third stage is the cooling stage. By re-introducing N2 to prevent oxidation, the silicon steel is avoided from coming into contact with harmful gases such as oxygen during the annealing process, reducing the occurrence of defects such as surface oxidation and cracks, ensuring the surface quality of the silicon steel, and improving the appearance quality and yield rate of the product.

[0031] In the high-temperature annealing method of oriented silicon steel, the first stage position is T3 to T16 in the annealing furnace; The parking space is where the trolley carrying the oriented silicon steel is located; When the oriented silicon steel is located at parking positions T3 to T7, adjust the temperature in the annealing furnace to 700℃±5℃; When the oriented silicon steel is located in the T8 position, adjust the temperature in the annealing furnace to 775℃±5℃; When the oriented silicon steel is located at the T9 position, adjust the temperature in the annealing furnace to 850℃±3℃; When the oriented silicon steel is located at the T10 position, adjust the temperature in the annealing furnace to 925℃±3℃; When the oriented silicon steel is located at the T11 parking position, adjust the temperature in the annealing furnace to 1000℃±3℃; When the oriented silicon steel is located at the T12 position, adjust the temperature in the annealing furnace to 1050℃±3℃; When the oriented silicon steel is located at the T13 position, adjust the temperature in the annealing furnace to 1100℃±3℃; When the oriented silicon steel is located in the T14 position, adjust the temperature in the annealing furnace to 1180℃±3℃; When the oriented silicon steel is located at parking positions T15~T16, adjust the temperature in the annealing furnace to 1200℃±3℃.

[0032] In this embodiment, the T3-T16 parking stage is a preheating and temperature-raising stage.

[0033] The above-mentioned T3-T16 parking spaces are where the trolleys carrying the semi-finished coils of oriented silicon steel are located; including the parking spaces below, there are a total of T1 to T31 parking spaces, and the T1 to T31 parking spaces are arranged sequentially in the annealing furnace, and the trolleys are parked in different positions, where different parking spaces are used for corresponding annealing processes.

[0034] During the preheating and heating phase (parking spaces T3-T16), this embodiment precisely adjusts the ratio of N2 and H2 to stabilize the hydrogen concentration at 50%. This ensures that the silicon steel can be heated steadily at the predetermined heating rate, avoids abnormal heating or process interruption caused by an unsuitable atmosphere, improves the stability and continuity of the annealing process, and thus enhances overall production efficiency.

[0035] Specifically, starting at parking lot T3, the preheating and temperature-raising phase begins. During this phase, the N2 and hydrogen (H2) levels must be gradually adjusted to maintain a stable hydrogen concentration of 50%. The furnace pressure is reduced from 300 Pa to 200 Pa and maintained stable. At parking lot T3, the N2 level is reduced to 8%, and H2 is introduced at a rate of 8%. For subsequent parking lots, the N2 and H2 levels are gradually fine-tuned according to the table data. During operation, it is crucial to precisely control the flow rates of N2 and H2. By adjusting the flow control valves on their respective pipelines and coordinating with the real-time data feedback from the mass flow meter, ensure that the two gases are mixed in proportion. For example, when adjusting the flow rate, the valve needs to be operated slowly to avoid excessive fluctuations in the hydrogen concentration ratio due to sudden changes in the flow rate. After each flow adjustment, wait 3-5 minutes until the gases are evenly mixed and the system is stable, then recheck the hydrogen concentration ratio value and furnace pressure. If they do not meet the requirements, continue to fine-tune. At the same time, pay close attention to the temperature rise in the furnace, because changes in the atmosphere ratio will affect the heating rate. It is necessary to ensure that the heating process is smooth and meets the process requirements.

[0036] During the initial reduction stage of annealing (T3-T9 stage), the hydrogen concentration is adjusted to 50% of the total gas ratio, and the nitrogen concentration is correspondingly adjusted to 50% of the total gas ratio. The strong reducing property of hydrogen is used to effectively remove the oxide layer on the surface of the silicon steel, while inhibiting the formation of a new oxide layer to ensure the purity of the silicon steel surface.

[0037] During the crystal structure optimization phase (T9-T16) during the middle of annealing, the hydrogen and nitrogen concentrations can be fine-tuned based on the specific composition and performance requirements of the silicon steel. This provides a stable protective atmosphere for silicon steel crystal growth, promotes more regular crystal orientation, and significantly improves the magnetic permeability of the silicon steel.

[0038] This method of precisely controlling the nitrogen and hydrogen concentration ratio in stages is key to improving the performance of grain-oriented silicon steel, reducing the product's hysteresis loss by 15%-20%. It also ensures the surface quality of the silicon steel, improving both the appearance and yield rate.

[0039] In the high-temperature annealing method of oriented silicon steel, the second stage position is T17 to T28 in the annealing furnace; When the oriented silicon steel is located at parking positions T17 to T20, adjust the temperature in the annealing furnace to 1200℃±3℃; When the oriented silicon steel is located at the T21 position, adjust the temperature in the annealing furnace to 1140℃±3℃; When the oriented silicon steel is located at the T22 position, adjust the temperature in the annealing furnace to 1080℃±3℃; When the oriented silicon steel is located at the T23 position, adjust the temperature in the annealing furnace to 1020℃±3℃; When the oriented silicon steel is located in the T24 position, adjust the temperature in the annealing furnace to 960℃±3℃; When the oriented silicon steel is located at the T25 position, adjust the temperature in the annealing furnace to 900℃±3℃; When the oriented silicon steel is located at the T26 position, adjust the temperature in the annealing furnace to 840℃±3℃; When the oriented silicon steel is located at position T27, adjust the temperature in the annealing furnace to 750℃±3℃; When the oriented silicon steel is located at the T28 position, the temperature in the annealing furnace is adjusted to 660℃±3℃.

[0040] In this embodiment, the parking stage T17-T28 is the core stage of high temperature annealing.

[0041] Specifically, this implementation creates an ideal atmosphere for recrystallization and grain growth in silicon steel by achieving a 100% hydrogen concentration during the core high-temperature annealing phase (positions T17-T28). This pure H2 atmosphere promotes uniform grain growth and texture optimization, effectively reducing iron loss and increasing magnetic permeability, significantly enhancing the magnetic properties of grain-oriented silicon steel, meeting the high-magnetic silicon steel requirements of high-end electrical equipment.

[0042] Positions T17-T28 are in the core stage of high-temperature annealing. At this point, N2 is discontinued and H2 is introduced entirely, reaching a hydrogen concentration of 100%. The furnace pressure is maintained at 200 Pa to promote recrystallization and grain growth of the silicon steel, enhancing its magnetic properties. Starting from position T17, the H2 injection rate is gradually adjusted according to the table data. For example, the H2 injection rate for positions T17 and T18 is 8, and the H2 injection rate for positions T23-T28 is increased to 12. During this phase of operation, first ensure that the N2 valve is completely closed to prevent N2 from mixing in and affecting H2 purity. Then, slowly increase the opening of the H2 valve to allow H2 to flow smoothly into the furnace. Because a pure H2 atmosphere is flammable and explosive, extreme caution is required during operation. Open flames, static electricity, and other ignition sources are strictly prohibited in the operating area. At the same time, continuously monitor the H2 flow rate, hydrogen concentration ratio, and furnace pressure to ensure that the H2 flow rate remains stable at the set value, the hydrogen concentration ratio remains at 100%, and the furnace pressure remains stable at 200 Pa. If any abnormal fluctuations in any parameters are detected, immediately inspect the gas pipelines, valves, and instruments to eliminate potential faults and ensure a safe and efficient high-temperature annealing process.

[0043] In the high-temperature annealing method of oriented silicon steel, the zeroth stage position is the T1 parking position ~ T2 parking position in the annealing furnace; When the oriented silicon steel is located in the T1 parking space, adjust the temperature in the annealing furnace to 550℃±5℃; When the oriented silicon steel is located in the T2 parking position, adjust the temperature in the annealing furnace to 700℃±5℃.

[0044] In this embodiment, the T1-T2 parking stage is the furnace purge and replacement stage.

[0045] At the T1-T2 parking bay, the primary task during this phase is to purge the furnace with nitrogen (N2), fully replacing the air inside. This creates an oxygen-free environment for subsequent silicon steel annealing and prevents oxidation. According to the table, the N2 flow rate at bays T1 and T2 is set at 20m³, respectively. H2 is not introduced, and the furnace pressure is stabilized at 300 Pa. During the purge operation, slowly open the N2 gas pipeline valve, allowing the N2 gas to flow smoothly into the furnace at a low flow rate to avoid the impact of excessive gas flow, which could damage the silicon steel coil. Simultaneously, monitor the oxygen content in the furnace in real time. When the oxygen content drops below 1%, the air replacement in the furnace is considered nearly complete. Throughout the purge process, continuously monitor the furnace pressure and adjust the N2 inflow or exhaust valve to ensure that the furnace pressure remains stable at 300 Pa. This prevents abnormal furnace pressure from affecting the purge effect or causing safety issues.

[0046] This embodiment uses N2 to purge and replace the air in the furnace during the preheating stage (T1-T2 parking space) to prevent oxidation, thereby avoiding contact between silicon steel and harmful gases such as oxygen during the annealing process, reducing the occurrence of defects such as surface oxidation and cracks, ensuring the surface quality of silicon steel, and improving the appearance quality and yield rate of the product.

[0047] In the high-temperature annealing method of oriented silicon steel, the third stage is located at positions T29 to T31 in the annealing furnace; With the trolley at parking position T29, adjust the temperature in the annealing furnace to 570℃±5℃; When the trolley is located at parking positions T30 to T31, adjust the temperature in the annealing furnace to room temperature.

[0048] In this embodiment, the parking stage from T29 to T31 is a cooling stage. During the cooling phase at parking spaces T29-T31, the H2 valves must be gradually closed, H2 flow stopped, and N2 reintroduced to reduce the hydrogen concentration to 0%. The furnace pressure is maintained at 200 Pa to prevent oxidation of the silicon steel during the cooling process. At parking space T29, the N2 flow rate is restored to 20% and the H2 flow rate is reduced to 0%. During operation, first slowly close the H2 valve. During the closing process, pay close attention to changes in the furnace pressure to prevent fluctuations in the furnace pressure due to a sudden drop in the H2 flow rate. After the H2 valve is completely closed, slowly open the N2 valve and begin to introduce N2 at a small flow rate. After the atmosphere in the furnace stabilizes, adjust the N2 flow rate to the set value. Continuously monitor the temperature in the furnace and adjust the N2 flow rate and furnace pressure as appropriate based on the cooling rate requirements. At the same time, prepare the appearance and performance inspections of the cooled silicon steel to ensure that the quality of the silicon steel meets the standards. Throughout the cooling stage, a high level of safety awareness must be maintained to prevent residual H2 from causing safety accidents.

[0049] This embodiment re-introduces N2 during the cooling stage (parking spaces T29-T31) to prevent oxidation, thereby avoiding contact of silicon steel with harmful gases such as oxygen during the annealing process, reducing the occurrence of defects such as surface oxidation and cracks, ensuring the surface quality of the silicon steel, and improving the appearance quality and yield rate of the product.

[0050] In the high temperature annealing method of oriented silicon steel, when the oriented silicon steel is located in the T1-T2 parking position, the furnace pressure in the annealing furnace is adjusted to 300 Pa; When the oriented silicon steel is located at parking positions T3 to T31, the furnace pressure in the annealing furnace is adjusted to 200Pa.

[0051] In the high-temperature annealing method of oriented silicon steel, the operation time of oriented silicon steel in each parking space from T1 to T31 is 5 to 7 hours.

[0052] In this embodiment, the operation time for each parking space is 5 to 7 hours, or 6 hours, and the total operation time is 31*6=186 hours.

[0053] In the high temperature annealing method of the oriented silicon steel, when the oriented silicon steel is located in parking spaces T1 to T2, nitrogen gas with a volume of 20 cubic meters at standard atmospheric pressure is introduced; When the oriented silicon steel is located in parking spaces T3 to T9, nitrogen and hydrogen with a volume of 8 cubic meters each under standard atmospheric pressure are introduced; When the oriented silicon steel is located in parking spaces T10 to T16, nitrogen and hydrogen with a volume of 6 cubic meters each under standard atmospheric pressure are introduced; When the oriented silicon steel is located in parking spaces T17 to T22, 8 cubic meters of hydrogen gas is introduced at standard atmospheric pressure; When the oriented silicon steel is located in parking spaces T23 to T28, 12 cubic meters of hydrogen gas is introduced at standard atmospheric pressure; When the oriented silicon steel is located in parking spaces T29 to T31, 20 cubic meters of nitrogen gas at standard atmospheric pressure is introduced; The volume of the annealing furnace inner cover corresponding to each parking space is 9.1m 3 .

[0054] In summary, the atmosphere and furnace pressure settings for each stage of the present invention are shown in Table 1: Table 1

[0055] And, the temperature control range of each parking space is shown in Table 2: Table 2

[0056] The high-temperature annealing method for grain-oriented silicon steel of the present invention can: 1. Optimizing Magnetic Properties: By precisely controlling the ratio of hydrogen (H2) and nitrogen (N2) during different annealing stages, such as achieving 100% hydrogen concentration during the core high-temperature annealing stage (positions T17-T28), an ideal atmosphere is created for recrystallization and grain growth in silicon steel. A pure H2 atmosphere promotes uniform grain growth and texture optimization, effectively reducing iron loss and increasing magnetic permeability, significantly enhancing the magnetic properties of grain-oriented silicon steel, meeting the high-magnetic silicon steel requirements of high-end electrical equipment. 2. Ensure surface quality: Reasonably set atmosphere parameters at different stages of annealing. For example, use N2 to purge and replace the air in the furnace during the preheating stage (T1-T2 parking spaces), and re-introduce N2 during the cooling stage (T29-T31 parking spaces) to prevent oxidation. This avoids contact of silicon steel with harmful gases such as oxygen during the annealing process, reduces the occurrence of defects such as surface oxidation and cracks, ensures the surface quality of silicon steel, and improves the appearance quality and yield rate of the product.

[0057] 3. Precise Process Matching: Differentiated atmosphere solutions are designed based on the characteristics of each silicon steel annealing stage, closely coordinating with process steps such as temperature control. For example, during the preheating and temperature-raising stages (parking spaces T3-T16), the ratio of N2 and H2 is precisely adjusted to maintain a stable hydrogen concentration of 50%. This ensures that the silicon steel heats up smoothly at the predetermined rate, avoiding abnormal temperature rises or process interruptions caused by an unsuitable atmosphere. This improves the stability and continuity of the annealing process, thereby enhancing overall production efficiency. 4. Reduce process adjustment time: The atmosphere design scheme has been optimized, and the atmosphere parameters at each stage are clear and reasonable. In actual production, operators can quickly and accurately perform atmosphere introduction operations according to the scheme, reducing the time wasted on exploring atmosphere parameters, shortening the production preparation cycle, enabling equipment to operate more efficiently, and increasing output per unit time.

[0058] 5. Conserving Gas Resources: The use of N2 and H2 has been meticulously designed, with gases introduced as needed at different stages. For example, H2 is not introduced during the period when it is not needed (between parking spaces T1 and T2), and N2 is reused during the cooling phase. This avoids unnecessary gas consumption and reduces gas procurement costs. Furthermore, rational gas usage reduces the amount of waste gas treated, lowering waste gas treatment costs. 6. Reduced defective product rates: This atmosphere design effectively improves product performance and surface quality, reducing the number of defective and scrapped products due to quality issues, reducing raw material waste, and saving production costs. At the same time, improved product quality also reduces rework and repair costs during subsequent processing, further reducing the overall cost of production.

[0059] Table 3 shows the average product pass rate and product defects for HG27 products at different hydrogen concentrations (pH 2%), with the trolley in the first stage position. Significant differences were observed across different hydrogen concentrations. The average pass rate at 50% reached 73%, far exceeding the other concentrations (17% at 40%, 45% at 60%, and 38% at 75%), achieving the highest quality performance among all production parameters. This data clearly demonstrates the decisive influence of hydrogen concentration on product quality and provides a clear parameter benchmark for production process optimization.

[0060] Table 3

[0061] According to one aspect of the present invention, an electronic device is provided, comprising: one or more processors, one or more memories, and one or more computer programs; wherein the processor is connected to the memory, and the one or more computer programs are stored in the memory; when the electronic device is running, the processor executes the one or more computer programs stored in the memory, so that the electronic device performs the high-temperature annealing method for grain-oriented silicon steel as described in the above technical solution.

[0062] According to one aspect of the present invention, a computer-readable storage medium is provided for storing computer instructions. When the computer instructions are executed by a processor, the high-temperature annealing method of grain-oriented silicon steel in the above technical solution is implemented.

[0063] Computer-readable storage media may include any medium capable of storing or transmitting information. Examples of computer-readable storage media include electronic circuits, semiconductor memory devices, ROM, flash memory, erasable ROM (EROM), floppy disks, CD-ROMs, optical disks, hard disks, fiber optic media, radio frequency (RF) links, and the like. The code segments may be downloaded via a computer network such as the Internet, an intranet, and the like.

[0064] The high-temperature annealing method of the present invention for oriented silicon steel comprises: The present invention provides a high-temperature annealing method for oriented silicon steel, which relates to the field of information retrieval, and the method is as follows: based on multiple telemetry parameters and operation symbols, a satellite telemetry parameter logical operation expression is constructed; according to the screening conditions of each telemetry parameter, a single-parameter valid time period set corresponding to each telemetry parameter is obtained; the single-parameter valid time period set is: a set of time periods when the telemetry parameter meets the corresponding screening conditions; the single-parameter valid time period set corresponding to the telemetry parameter is substituted into the satellite telemetry parameter logical operation expression and solved to obtain the effective time of multiple telemetry parameters.

[0065] Furthermore, it should be noted that the present invention may be provided as a method, apparatus, or computer program product. Thus, embodiments of the present invention may take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of the present invention may take the form of a computer program product embodied on one or more computer-usable storage media containing computer-usable program code.

[0066] The embodiments of the present invention are described with reference to the flowcharts and / or block diagrams of the methods, terminal devices (systems), and computer program products according to the embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of the processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, an embedded processor, or other programmable data processing terminal device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing terminal device generate instructions for implementing the process in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0067] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing terminal device to operate in a specific manner, so that the instructions stored in the computer readable memory produce a manufactured product including an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 These computer program instructions can also be loaded onto a computer or other programmable data processing terminal device, so that a series of operation steps are executed on the computer or other programmable terminal device to produce a computer-implemented process, thereby providing instructions for implementing the process in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0068] It should also be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or terminal device comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or terminal device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or terminal device comprising the element.

[0069] Finally, it should be noted that the above is a preferred embodiment of the present invention. It should be noted that although the preferred embodiment of the present invention has been described, it is clear that those skilled in the art, once they understand the basic inventive concept of the present invention, can make various improvements and modifications without departing from the principles of the present invention. Such improvements and modifications should also be considered as within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including the preferred embodiment and all changes and modifications that fall within the scope of the embodiments of the present invention.

Claims

1. A high temperature annealing method for oriented silicon steel, characterized in that: The method comprises: When the oriented silicon steel is located in the first stage of the annealing furnace, the volume ratio of nitrogen and hydrogen in the annealing furnace is adjusted to 50% each; and the temperature in the annealing furnace is adjusted from low to high, and the temperature adjustment range is 700° C. to 1200° C.; When the oriented silicon steel is located in the second stage of the annealing furnace, the volume ratio of hydrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 1200° C. to 660° C.; The oriented silicon steel is located successively at the first stage position and the second stage position.

2. The high temperature annealing method for grain-oriented silicon steel according to claim 1, characterized in that: Also includes: When the oriented silicon steel is located at the zero stage in the annealing furnace, the volume proportion of nitrogen in the annealing furnace is adjusted to 100%; and adjusting the temperature in the annealing furnace from low to high, wherein the temperature adjustment range is 550° C. to 700° C.; The oriented silicon steel is located successively at the zeroth stage position and the first stage position.

3. The high temperature annealing method for grain-oriented silicon steel according to claim 1, characterized in that: Also includes: When the oriented silicon steel is located in the third stage of the annealing furnace, the volume ratio of nitrogen in the annealing furnace is adjusted to 100%; and the temperature in the annealing furnace is adjusted from high to low, and the temperature adjustment range is 570° C. to room temperature; The oriented silicon steel is located successively at the second stage position and the third stage position.

4. The high temperature annealing method for grain-oriented silicon steel according to any one of claims 1 to 3, characterized in that: The first stage is located at parking spaces T3 to T16 in the annealing furnace; The parking space is where the trolley carrying the oriented silicon steel is located; When the oriented silicon steel is located at parking positions T3 to T7, adjust the temperature in the annealing furnace to 700℃±5℃; When the oriented silicon steel is located in the T8 position, adjust the temperature in the annealing furnace to 775℃±5℃; When the oriented silicon steel is located at the T9 position, adjust the temperature in the annealing furnace to 850℃±3℃; When the oriented silicon steel is located at the T10 position, adjust the temperature in the annealing furnace to 925℃±3℃; When the oriented silicon steel is located at the T11 parking position, adjust the temperature in the annealing furnace to 1000℃±3℃; When the oriented silicon steel is located at the T12 position, adjust the temperature in the annealing furnace to 1050℃±3℃; When the oriented silicon steel is located at the T13 position, adjust the temperature in the annealing furnace to 1100℃±3℃; When the oriented silicon steel is located in the T14 position, adjust the temperature in the annealing furnace to 1180℃±3℃; When the oriented silicon steel is located at parking positions T15~T16, adjust the temperature in the annealing furnace to 1200℃±3℃.

5. The high temperature annealing method for grain-oriented silicon steel according to claim 4, characterized in that: The second stage is located at parking spaces T17 to T28 in the annealing furnace; When the oriented silicon steel is located at parking positions T17 to T20, adjust the temperature in the annealing furnace to 1200℃±3℃; When the oriented silicon steel is located at the T21 position, adjust the temperature in the annealing furnace to 1140℃±3℃; When the oriented silicon steel is located at the T22 position, adjust the temperature in the annealing furnace to 1080℃±3℃; When the oriented silicon steel is located at the T23 position, adjust the temperature in the annealing furnace to 1020℃±3℃; When the oriented silicon steel is located in the T24 position, adjust the temperature in the annealing furnace to 960℃±3℃; When the oriented silicon steel is located at the T25 position, adjust the temperature in the annealing furnace to 900℃±3℃; When the oriented silicon steel is located at the T26 position, adjust the temperature in the annealing furnace to 840℃±3℃; When the oriented silicon steel is located at position T27, adjust the temperature in the annealing furnace to 750℃±3℃; When the oriented silicon steel is located at the T28 position, the temperature in the annealing furnace is adjusted to 660℃±3℃.

6. The high temperature annealing method for grain-oriented silicon steel according to claim 5, characterized in that: The zeroth stage position is the T1~T2 parking space in the annealing furnace; When the oriented silicon steel is located in the T1 parking space, adjust the temperature in the annealing furnace to 550℃±5℃; When the oriented silicon steel is located in the T2 parking position, adjust the temperature in the annealing furnace to 700℃±5℃.

7. The high temperature annealing method for grain-oriented silicon steel according to claim 6, characterized in that: The third stage is located at parking spaces T29 to T31 in the annealing furnace; When the oriented silicon steel is located in the T29 position, adjust the temperature in the annealing furnace to 570℃±5℃; When the oriented silicon steel is located at parking positions T30 to T31, the temperature in the annealing furnace is adjusted to room temperature.

8. The high temperature annealing method for grain-oriented silicon steel according to claim 7, characterized in that: When the oriented silicon steel is located at parking positions T1 to T2, adjust the furnace pressure in the annealing furnace to 300 Pa; When the oriented silicon steel is located at parking positions T3 to T31, the furnace pressure in the annealing furnace is adjusted to 200Pa.

9. The high temperature annealing method for grain-oriented silicon steel according to claim 7 or 8, characterized in that: The operation time of the oriented silicon steel in each parking space from T1 to T31 is 5 to 7 hours.

10. The high temperature annealing method for grain-oriented silicon steel according to claim 9, characterized in that: When the oriented silicon steel is located in parking spaces T1 to T2, nitrogen with a volume of 20 cubic meters under standard atmospheric pressure is introduced; When the oriented silicon steel is located in parking spaces T3 to T9, nitrogen and hydrogen with a volume of 8 cubic meters each under standard atmospheric pressure are introduced; When the oriented silicon steel is located in parking spaces T10 to T16, nitrogen and hydrogen with a volume of 6 cubic meters each under standard atmospheric pressure are introduced; When the oriented silicon steel is located in parking spaces T17 to T22, 8 cubic meters of hydrogen gas is introduced at standard atmospheric pressure; When the oriented silicon steel is located in parking spaces T23 to T28, 12 cubic meters of hydrogen gas is introduced at standard atmospheric pressure; When the oriented silicon steel is located in parking spaces T29 to T31, 20 cubic meters of nitrogen gas at standard atmospheric pressure is introduced; The volume of the annealing furnace inner cover corresponding to each parking space is 9.1m 3 .

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