A method for forming a stainless steel plate

Abstract

The present application relates to the technical field of steel forming processing technology, and discloses a stainless steel plate forming method, comprising the following steps: Step 1: preparing a stainless steel plate with a blank thickness of not less than 30 mm, and forming the stainless steel into a curved plate by using a mold on hydraulic equipment; Step 2: inspecting the curved plate using a three-dimensional profiling detection template; Step 3: placing the curved plate that has passed the inspection in a vacuum furnace and heat-treating the curved plate to eliminate tissue stress, thereby obtaining a curved plate with low stress and low magnetic permeability; Step 4: after the curved plate is heat-treated, fine-shaping the curved plate using a mold and inspecting the curved plate using a three-dimensional profiling detection template; Step 5: using a global three-dimensional scanner to perform contour inspection on the curved plate that has passed the inspection; wherein the magnetic permeability of the curved plate after heat treatment is less than 1.03. The forming method of the present application has the advantages of simple operation, high processing accuracy, and the ability to effectively control residual stress and magnetic permeability.

Description

Technical Field

[0001] The present application relates to the technical field of steel forming processing technology, and in particular to a forming method of a stainless steel plate. Background Art

[0002] Austenitic stainless steel is widely used in fields such as nuclear energy equipment due to its corrosion resistance, high temperature resistance and high strength. Thanks to its excellent processing ductility, austenitic stainless steel is often used in the forming processing of curved surface structures of various equipment.

[0003] The austenitic stainless steel used in nuclear fusion devices must endure long periods of high temperature service, placing extremely high demands on the thickness, stress, and magnetic permeability of the stainless steel sheets used in these devices. Therefore, an efficient forming method that can control the residual stress and magnetic permeability of stainless steel sheets is urgently needed to address the compression forming issues of nuclear fusion devices and ensure the construction of fusion reactors.

[0004] At present, in the stainless steel head forming process, stainless steel is usually heated to a preset temperature (such as 950℃) and kept warm before being pressed into shape to shorten the hot forming time and reduce energy consumption. This is suitable for the forming of thin-walled and large-diameter heads. However, stainless steel plates are prone to surface oxidation during the hot pressing process, which reduces the surface corrosion resistance of the stainless steel plates and affects the forming effect of the stainless steel plates. In addition, the material is prone to deformation after pressing at high temperatures, affecting the dimensional accuracy of the final product.

[0005] Flexible roll forming is a type of cold forming technology. However, it can only be applied to materials with good shapeability and thin plate thickness, making it difficult to apply to the forming of medium and thick austenitic stainless steel plates. Furthermore, during cold forming, austenitic stainless steel can partially transform the austenite structure into martensite, which is ferromagnetic and affects the material's magnetic permeability. Furthermore, the plastic deformation of the material also introduces residual stress, reducing its strength. Summary of the Invention

[0006] The present application aims to address at least one of the technical problems existing in the prior art. To this end, one object of the present application is to provide a method for forming a stainless steel plate. The stainless steel plate produced by the method has low residual stress and low magnetic permeability, can be used in fusion reactor devices, and has high forming efficiency.

[0007] According to the forming method of the stainless steel plate of the embodiment of the present application, the forming method includes the following steps: Step 1: Prepare a stainless steel plate with a blank thickness of not less than 30 mm, and use a mold on hydraulic equipment to initially press the stainless steel plate into a curved plate; Step 2: Use a three-dimensional profiling detection template to detect the curved plate; Step 3: Place the curved plate that has passed the inspection in a vacuum furnace and heat-treat the curved plate to eliminate tissue stress, so as to obtain a curved plate with low stress and low magnetic permeability; Step 4: After the curved plate is heat-treated, use the mold to fine-shape the curved plate, and use a three-dimensional profiling detection template to detect the curved plate; Step 5: Use a global three-dimensional scanner to perform contour detection on the curved plate that has passed the inspection; wherein, the magnetic permeability of the curved plate after heat treatment is lower than 1.03.

[0008] According to some embodiments of the present application, the step one further includes: initially press-forming the stainless steel plate into the curved plate with a deformation rate greater than 15%.

[0009] According to some embodiments of the present application, step three also includes: performing solution heat treatment on the curved panel using a vacuum furnace, first heating the curved panel to a first preset temperature, then heating the curved panel to a second preset temperature at a first preset heating rate, then keeping the curved panel warm for a first preset time, and finally cooling the curved panel by water.

[0010] According to some embodiments of the present application, the first preset temperature is 300°C, the first preset heating rate is 55°C / h-200°C / h, the second preset temperature is 1060±15°C, and the first preset time is 45 minutes-70 minutes.

[0011] According to some embodiments of the present application, step three also includes: first heating the curved panel to a third preset temperature, then heating the curved panel to a fourth preset temperature at a second preset heating rate, then keeping the curved panel warm for a second preset time and then cooling the curved panel to a fifth preset temperature at a third preset heating rate, and finally air cooling the curved panel.

[0012] According to some embodiments of the present application, the third preset temperature is ≤200°C, the second preset heating rate is ≤60°C / h, the fourth preset temperature is 405±15°C, the second preset time is 4h-6h, the third preset heating rate is ≤60°C / h and the fifth preset temperature is 200°C.

[0013] According to some embodiments of the present application, step two also includes: determining that the curved panel has passed the initial press when the maximum gap between the three-dimensional profiling detection template and the curved panel is not higher than 8 mm; determining that the curved panel has failed the initial press when the maximum gap between the three-dimensional profiling detection template and the curved panel is higher than 8 mm, and cold pressing the curved panel again using a mold through hydraulic equipment.

[0014] According to some embodiments of the present application, step four also includes: after the curved panel is finely shaped, the maximum gap between the three-dimensional profiling detection template and the curved panel is not higher than 2.5 mm, determining that the fine-shaped curved panel is qualified; after the curved panel is finely shaped, the maximum gap between the three-dimensional profiling detection template and the curved panel is higher than 2.5 mm, determining that the fine-shaped curved panel is unqualified, and fine-shaping the curved panel again through the mold.

[0015] According to some embodiments of the present application, step five further includes: using a global three-dimensional scanner to detect that the contour deviation of the curved panel is within 2.5 mm, determining that the curved panel is qualified.

[0016] According to some embodiments of the present application, step three further includes: after placing the curved panel in the vacuum furnace, evacuating the vacuum furnace to a preset vacuum degree, and then heating the curved panel along with the furnace.

[0017] The stainless steel plate forming method according to the embodiment of the present application has at least the following advantages compared with the prior art:

[0018] This application utilizes cold forming, heat treatment, and finishing techniques to form austenitic stainless steel, offering simple operation, high machining precision, and effective control of residual stress and magnetic permeability. The three-dimensional profiling test sample is intuitive and easy to operate. The vacuum furnace heat treatment process eliminates stress accumulation caused by cold forming, restores the material's plasticity and toughness, transforms martensite into austenite, and controls the material's magnetic permeability, enabling the production of stainless steel sheets that meet the requirements for fusion reactor construction.

[0019] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become obvious from the description below, or will be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0021] Figure 1 is a flow chart of a stainless steel plate forming method according to one embodiment of the present application;

[0022] Figure 2 is a process curve diagram of the solution heat treatment according to one embodiment of the present application;

[0023] Figure 3 is a stress relief heat treatment process curve diagram according to one embodiment of the present application;

[0024] Figure 4a This is a schematic diagram of the forming of a curved panel according to an embodiment of the present application. Figure 1 ;

[0025] Figure 4b This is a schematic diagram of the forming of a curved panel according to an embodiment of the present application. Figure 2 ;

[0026] Figure 5 This is a microstructure diagram of a stainless steel plate after solution heat treatment according to one embodiment of the present application. DETAILED DESCRIPTION

[0027] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0028] refer to Figure 1-Figure 5 The forming method of the stainless steel plate according to the embodiment of the present application is described. The curved plate prepared by the forming method of the stainless steel plate in the present application can meet the construction requirements of the nuclear fusion device and can be applied to the construction of the nuclear fusion device.

[0029] The forming method of the stainless steel plate according to the embodiment of the present application includes the following steps: Step 1: Prepare a stainless steel plate with a blank thickness of not less than 30 mm, and use a mold on hydraulic equipment to initially press the stainless steel plate into a curved plate; Step 2: Use a three-dimensional profiling detection template to detect the curved plate; Step 3: Place the curved plate that has passed the inspection in a vacuum furnace and heat-treat the curved plate to eliminate tissue stress, so as to obtain a curved plate with low stress and low magnetic permeability; Step 4: After the curved plate is heat-treated, use a mold to fine-shape the curved plate, and use a three-dimensional profiling detection template to detect the curved plate; Step 5: Use a global three-dimensional scanner to perform contour detection on the curved plate that has passed the inspection.

[0030] In the present application, the stainless steel plate is first subjected to an initial press forming process by hydraulic equipment to press the stainless steel plate with a blank thickness of 30 mm into a curved plate, and the shape of the stainless steel plate is changed by cold pressing.

[0031] It should be noted that, referring to Figure 4aand Figure 4b As shown, in some embodiments, the curved panel obtained by the hydraulic equipment using a mold cold pressing process can be constructed as a plate structure with a partially arc-shaped extension, that is, the stainless steel plate is constructed as a curved panel with a transition between two flat plate sections through an arc-shaped plate section; in other embodiments, the curved panel obtained by the hydraulic equipment using a mold cold pressing process can also be constructed as a plate structure with an overall arc-shaped extension.

[0032] Furthermore, after the stainless steel sheet is cold-pressed, the curved panel is tested using a three-dimensional profiling test sample to determine the qualified status of the cold-pressing treatment. Furthermore, after the curved panel is confirmed to have passed the cold-pressing treatment, it can be heat-treated in a vacuum furnace to eliminate the stress generated by the cold and hot processing, allowing the alloy to recrystallize and soften the material, resulting in a curved panel with low stress and low magnetic permeability.

[0033] It is understandable that during the heat treatment process of the curved panel, the curved panel needs to be arranged in a vacuum furnace, that is, the heat treatment process of the curved panel is carried out in a vacuum environment, which can effectively prevent the surface of the curved panel from being oxidized during the heat treatment process, reduce the risk of problems such as slagging of the curved panel during the heat treatment process, and improve the heat treatment effect of the curved panel.

[0034] The magnetic permeability of the curved plate after heat treatment is lower than 1.03, so that the curved plate after heat treatment can meet the use requirements of the fusion reactor device.

[0035] Reference Figure 1 After the curved panel is heat treated, it is fine-shaped using a mold to further reduce the forming error and improve the forming accuracy of the curved panel. After the curved panel is fine-machined, it can be further tested using a three-dimensional profiling test sample to determine its qualified state after fine-machining.

[0036] Finally, a global three-dimensional scanner is used to detect the contour of the curved plate after passing the inspection, so as to comprehensively check the contour of the curved plate, and then the above-mentioned stainless steel plate forming method is used to prepare plate materials that meet the construction and use requirements of fusion reactor devices.

[0037] In the forming method for stainless steel sheet applied in this application, the stainless steel sheet is first cold-pressed using a mold on hydraulic equipment (i.e., the aforementioned initial pressing to form a curved sheet). The curved sheet is then heat-treated in a vacuum furnace. This heat treatment is performed in a vacuum environment to prevent surface oxidation and other issues during the heat treatment process. This also reduces residual stress in the formed curved sheet and controls the material's magnetic permeability. Furthermore, after the heat treatment is completed, the curved sheet undergoes a finishing process to improve its forming accuracy.

[0038] It is understandable that since the fine shaping process is carried out after the curved panel is heat treated, that is, the fine shaping process of the curved panel can be carried out at room temperature, it can avoid deformation of the curved panel caused by shaping at high temperature, which affects the product dimensional accuracy of the curved panel.

[0039] In some embodiments of the present application, step one also includes: initially press-forming the stainless steel plate into a curved plate with a deformation rate greater than 15%, so that the stainless steel plate can be initially press-formed into a shape with a deformation amount that can meet the requirements of fusion reactor device construction.

[0040] It should be noted that the deformation of the stainless steel plate after the initial pressure treatment by the hydraulic equipment can be 20%, 50%, 54%, etc. The specific deformation of the stainless steel plate after the initial pressure treatment can be designed according to the construction and use requirements of the fusion reactor device.

[0041] In some embodiments of the present application, step three also includes: performing solution heat treatment on the curved panel using a vacuum furnace, first heating the curved panel to a first preset temperature, then heating the curved panel to a second preset temperature at a first preset heating rate, then keeping the curved panel warm for a first preset time, and finally cooling the curved panel by water.

[0042] Among them, in step three, the curved plate is stress-eliminated by solution heat treatment. The curved plate can be heated to a high-temperature austenite zone and kept warm to fully dissolve the excess phase to obtain a uniform supersaturated solid solution, thereby improving the plasticity and toughness of the curved plate and eliminating residual stress.

[0043] It can be understood that after the curved panel is placed in the vacuum furnace, the curved panel can be heated along with the furnace to increase the temperature of the curved panel to a second preset temperature, and after the insulation operation, the curved panel can be quickly cooled by water cooling, so that the curved panel after heat treatment can achieve a good stress relief effect.

[0044] like Figure 2 As shown, in a further embodiment of the present application, the first preset temperature is 300°C, the first preset heating rate is 55°C / h-200°C / h, the second preset temperature is 1060±15°C, and the first preset time is 45 minutes-70 minutes.

[0045] Reference Figure 2During the heat treatment of the curved plate in a vacuum furnace, the curved plate is first heated to 300°C, then heated to a temperature range of 1060±15°C at a heating rate of 55°C / h-200°C / h. The curved plate is then kept at 1060±15°C for 45-70 minutes, and finally cooled by water cooling. It can be understood that when the above parameters are met, the heat treatment time of the curved plate can be shortened, accelerating the forming efficiency of the stainless steel plate.

[0046] In some other embodiments of the present application, step three further includes: first heating the curved panel to a third preset temperature, then heating the curved panel to a fourth preset temperature at a second preset heating rate, then cooling the curved panel to a fifth preset temperature at the third preset heating rate after holding the curved panel at the temperature for a second preset time, and finally air cooling the curved panel. Thus, stress relief heat treatment of the curved panel is achieved.

[0047] It can be understood that after the curved panel is placed in the vacuum furnace, the curved panel can be heated along with the furnace to increase the temperature of the curved panel to a third preset temperature, and the curved panel can be cooled by air cooling during the insulation operation, so that the curved panel after heat treatment can achieve a good stress relief effect.

[0048] like Figure 3 As shown, in a further embodiment of the present application, the third preset temperature is ≤200°C, the second preset heating rate is ≤60°C / h, the fourth preset temperature is 405±15°C, the second preset time is 4h-6h, the third preset heating rate is ≤60°C / h and the fifth preset temperature is 200°C.

[0049] Reference Figure 3 During the heat treatment of the curved panel in a vacuum furnace, the curved panel is first heated to ≤200°C, then heated to a temperature within the range of 405±15°C at a heating rate of ≤60°C / h. The curved panel is then held at 405±15°C for 4-6 hours, and finally cooled by air cooling. It is understood that when the above parameters are met, heat treating the curved panel at a lower temperature can reduce the energy consumption required during the heat treatment of the curved panel.

[0050] It should be noted that the aforementioned "curved panel at a lower temperature" refers to the third preset temperature being compared to the first preset temperature, and the fourth preset temperature being compared to the second preset temperature. In the above embodiment, by lowering the temperature of the curved panel during the heat treatment process and appropriately extending the holding period, the curved panel achieves excellent stress relief while reducing energy consumption.

[0051] In some embodiments of the present application, step two also includes: determining that the initial press of the curved panel is qualified when the maximum gap between the three-dimensional profiling detection template and the curved panel is not higher than 8 mm; determining that the initial press of the curved panel is unqualified when the maximum gap between the three-dimensional profiling detection template and the curved panel is higher than 8 mm, and cold pressing the curved panel again using a mold through hydraulic equipment.

[0052] It can be understood that, in the process of inspecting the curved panel through the three-dimensional profiling detection template, when the maximum gap between the three-dimensional profiling detection template and the curved panel is within the range of 8 mm, it means that the error of the curved panel after the initial pressing treatment is within the required range, that is, the curved panel passes the initial pressing and step three can be further executed; when the maximum gap between the three-dimensional profiling detection template and the curved panel is greater than 8 mm, it means that the error of the curved panel after the initial pressing treatment exceeds the required range, that is, the curved panel fails the initial pressing and step one needs to be re-executed.

[0053] Therefore, the forming process of the curved panel can be initially inspected based on step 2 to ensure the processing accuracy of the curved panel.

[0054] In some embodiments of the present application, step four also includes: after the curved panel is finely shaped, the maximum gap between the three-dimensional profiling detection template and the curved panel is not higher than 2.5 mm, determining that the fine shaping of the curved panel is qualified; after the curved panel is finely shaped, the maximum gap between the three-dimensional profiling detection template and the curved panel is higher than 2.5 mm, determining that the fine shaping of the curved panel is unqualified, and re-processing the curved panel through the mold.

[0055] It can be understood that, in the process of inspecting the curved panel through the three-dimensional profiling detection template, when the maximum gap between the three-dimensional profiling detection template and the curved panel is within the range of 2.5 mm, it means that the error of the curved panel after fine shaping is within the required range, that is, the fine shaping of the curved panel is qualified and step five can be further performed; when the maximum gap between the three-dimensional profiling detection template and the curved panel is greater than 2.5, it means that the error of the curved panel after fine shaping exceeds the required range, that is, the fine shaping of the curved panel is unqualified and the fine shaping process needs to be re-executed.

[0056] Therefore, the curved plate after heat treatment can be precision-tested again based on step 4 to ensure the processing accuracy of the curved plate.

[0057] In some embodiments of the present application, step five also includes: using a global three-dimensional scanner to detect the contour deviation of the curved panel and determining that the curved panel is qualified within 2.5 mm, thereby fully detecting the curved panel after fine shaping to ensure the processing accuracy of the curved panel.

[0058] It is understood that when using a global 3D scanner to detect the contour of a curved panel, multiple contour points can be selected to improve the detection effect of the curved panel. The number of contour points can be 500, 1000, etc. The specific number of contour points can be set according to the shape and size of the curved panel.

[0059] It should be noted that when the deviation of the local contour of the curved panel detected by the global 3D scanner is higher than 2.5 mm, the error can be reduced by fine machining to further improve the forming accuracy of the curved panel.

[0060] In some embodiments of the present application, step three also includes: after placing the curved panel in a vacuum furnace, evacuating the vacuum furnace to a preset vacuum degree, and then heating the curved panel along with the furnace to prevent surface oxidation of the curved panel during the heat treatment process, thereby improving the heat treatment effect of the curved panel.

[0061] Among them, the preset vacuum degree can be set to be lower than 5×10 -2 Pa.

[0062] The stainless steel plate forming method according to the embodiment of the present application has at least the following advantages compared with the prior art:

[0063] First, the stainless steel plate is cold-formed using a mold using hydraulic equipment (i.e., the initial pressing treatment mentioned above), and the cold-pressed curved plate is placed in a vacuum furnace for heat treatment to eliminate residual stress and reduce the magnetic permeability of the curved plate, so that the curved plate meets the use requirements of the construction of fusion reactor devices. It can also prevent the curved plate from surface oxidation and other problems during the heat treatment process, ensuring the surface corrosion resistance of the curved plate. In addition, the cold forming method can avoid the problem of easy deformation of the material during high-temperature pressing, which helps to improve the product dimensional accuracy of the curved plate.

[0064] At the same time, during the forming process of the stainless steel plate, multiple inspections can be performed through step 2, step 4, and step 5 to ensure the processing accuracy of the curved plate.

[0065] In summary, this application utilizes cold forming, heat treatment, and finishing techniques to form austenitic stainless steel, offering advantages such as ease of operation, high machining precision, and effective control of residual stress and magnetic permeability. The three-dimensional profiling test sample is intuitive and easy to operate. The vacuum furnace heat treatment process eliminates stress accumulation caused by cold forming, restores the material's plasticity and toughness, transforms martensite into austenite, and controls the material's magnetic permeability, enabling the production of stainless steel sheets that meet the requirements for fusion reactor construction.

[0066] In a specific embodiment of the present application, an austenitic stainless steel plate with a thickness of 46 mm and a size of 1200 mm × 300 mm is prepared. The austenitic stainless steel plate is initially press-formed into a curved plate by using a mold on hydraulic equipment, and the deformation rate of the curved plate after pressing reaches 54%.

[0067] Furthermore, a three-dimensional profiling detection template is used to perform dimensional inspection on the curved panel, and after the gap between the curved panel and the three-dimensional profiling detection template meets the requirements, a vacuum furnace is used to perform solution heat treatment on the curved panel.

[0068] The specific working conditions of the solution heat treatment are as follows: first, the curved plate is heated to 300°C in the furnace, then heated to 1060°C±15°C at a heating rate not higher than 200°C / h, and then kept warm for 45 minutes to 75 minutes, and finally, the curved plate is water-cooled to room temperature.

[0069] After the curved plate is heat-treated (i.e., cooled to room temperature), it is finely shaped (cold-shaped) using a mold. After fine-shaping, the curved plate is inspected using a profiling test specimen. Once the maximum gap between the curved plate and the test specimen meets the required value (e.g., no greater than 2.5 mm), the curved plate is profile-checked using a global 3D scanner, with the maximum profile deviation controlled within 2.5 mm. This results in a curved austenitic stainless steel plate with high machining accuracy, low stress, and low magnetic permeability.

[0070] Furthermore, the austenitic stainless steel plates obtained by the above-mentioned stainless steel plate forming method were subjected to room temperature tensile testing (see Table 1 below), high temperature tensile testing (see Table 2 below), room temperature impact testing (see Table 3 below), grain size testing (see Table 4 below), and magnetic permeability testing (see Table 5 below).

[0071] Table 1: Room temperature tensile test results

[0072]

[0073] Table 2: High temperature tensile test results

[0074]

[0075] Table 3: Normal temperature shock test results

[0076]

[0077] Table 4: Grain size test results

[0078]

[0079] Table 5: Magnetic permeability test results after solution heat treatment

[0080]

[0081] As shown in the above table, the room temperature tensile test yield strength of the austenitic stainless steel plate prepared by the above stainless steel plate forming method is 273MPa and the tensile strength is 602MPa. The yield strength of the stainless steel plate is required to be greater than 220MPa and the tensile strength is required to be greater than 525MPa. Therefore, the room temperature tensile test meets the requirements; the high temperature tensile test yield strength of the austenitic stainless steel plate is 203MPa and the tensile strength is 494MPa. The yield strength of the stainless steel plate is required to be greater than 135MPa and the tensile strength is required to be greater than 525MPa. The specified value requirement for tensile strength is >415MPa, so the high-temperature tensile test meets the requirement; the average value of the absorbed energy in the room temperature impact test of the austenitic stainless steel plate is 422J and the minimum value is 406J, and the specified value requirement for the impact absorbed energy of the stainless steel plate is >122J, so the room temperature impact test meets the requirement; the grain size test value of the austenitic stainless steel plate is level 5, and the specified value requirement for the grain size of the stainless steel plate is ≥level 4, so the grain size test meets the requirement; the maximum value of the magnetic permeability test of the austenitic stainless steel plate is 1.005, which is lower than the requirement of 1.03.

[0082] Therefore, the stainless steel plate forming method of the embodiment of the present application can produce austenitic stainless steel press-formed products with a thickness of 46 mm and a material deformation rate of 54%, and has the advantages of high processing precision, reducing residual stress after forming, and controlling the magnetic permeability of the material. Moreover, the process flow is simple and the forming processing of austenitic stainless steel can be completed quickly and efficiently.

[0083] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on this application.

[0084] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0085] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0086] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and intent of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A method for forming an austenitic stainless steel plate, characterized in that: The forming method comprises the following steps: Step 1: Prepare an austenitic stainless steel plate with a thickness of not less than 30 mm, and use a mold on a hydraulic device to initially press the austenitic stainless steel plate into a curved plate; Step 2: Using a three-dimensional profiling test sample to test the curved panel; Step 3: placing the curved panel after the inspection into a vacuum furnace and performing heat treatment on the curved panel to eliminate tissue stress to obtain the curved panel with low stress and low magnetic permeability, and performing solution heat treatment on the curved panel using a vacuum furnace, first heating the curved panel to a first preset temperature, then heating the curved panel to a second preset temperature at a first preset heating rate, then keeping the curved panel warm for a first preset time, and finally cooling the curved panel with water, wherein the first preset temperature is 300°C, the first preset heating rate is 55°C / h-200°C / h, the second preset temperature is 1060±15°C, and the first preset time is 45 minutes-70 minutes; Step 4: After the curved panel is heat treated, the mold is used to fine-tune the curved panel, and the curved panel is tested using a three-dimensional profiling test sample; Step 5: Using a global 3D scanner to perform contour detection on the curved panel that has passed the inspection; Wherein, the magnetic permeability of the curved plate after heat treatment is lower than 1.

03.

2. The forming method of austenitic stainless steel sheet according to claim 1, characterized in that: The step 1 further includes: initially pressing the austenitic stainless steel plate into the curved plate with a deformation rate greater than 15%.

3. The forming method of austenitic stainless steel sheet according to claim 1, characterized in that: The step three also includes: first heating the curved panel to a third preset temperature, then heating the curved panel to a fourth preset temperature at a second preset heating rate, then keeping the curved panel warm for a second preset time, then cooling the curved panel to a fifth preset temperature at a third preset heating rate, and finally air cooling the curved panel.

4. The forming method of austenitic stainless steel sheet according to claim 3, characterized in that: The third preset temperature is ≤200°C, the second preset heating rate is ≤60°C / h, the fourth preset temperature is 405±15°C, the second preset time is 4h-6h, the third preset heating rate is ≤60°C / h and the fifth preset temperature is 200°C.

5. The forming method of austenitic stainless steel sheet according to claim 1, characterized in that: The step 2 further includes: determining that the curved panel has passed the initial pressure test when the maximum gap between the three-dimensional profiling detection sample and the curved panel is no greater than 8 mm; When the maximum gap between the three-dimensional profiling detection template and the curved panel is higher than 8 mm, it is determined that the curved panel has failed the initial pressing, and the curved panel is cold-pressed again using a mold through hydraulic equipment.

6. The forming method of austenitic stainless steel sheet according to claim 1, characterized in that: The step 4 further includes: after the curved panel is finely shaped, determining that the curved panel is qualified when the maximum gap between the three-dimensional profiling detection template and the curved panel is not greater than 2.5 mm; After the curved panel is finely shaped, if the maximum gap between the three-dimensional profiling detection template and the curved panel is higher than 2.5 mm, it is determined that the curved panel is unqualified, and the curved panel is finely shaped again using the mold.

7. The forming method of an austenitic stainless steel plate according to claim 1, characterized in that: The step five also includes: using a global three-dimensional scanner to detect the contour deviation of the curved panel and determining that the curved panel is qualified if it is within 2.5 mm.

8. The forming method of austenitic stainless steel sheet according to claim 1, characterized in that: The step three also includes: after placing the curved panel in the vacuum furnace, evacuating the vacuum furnace to a preset vacuum degree, and then heating the curved panel along with the furnace.

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