An apparatus and method for preparing ultrawide equiaxed fine-grained thin plates

Abstract

This invention belongs to the field of aerospace manufacturing technology and discloses an apparatus and method for preparing ultra-wide equiaxed fine-grained thin plates. The apparatus includes a worktable, a rotary table, a motor, a support arm, and a movable pressurizing mechanism fixed to the support arm. The motor drives the rotary table to rotate synchronously with the original billet. High-speed rotation, high-frequency vibration, and ball stirring, along with thickness extrusion of the rotating billet, induce a point-to-point kneading effect on both sides of the hot semi-solid, semi-viscous material, resulting in grain breakage, dynamic recrystallization, and superplastic thinning to obtain ultra-wide equiaxed fine-grained thin plate billets. This invention overcomes the technical difficulty of preparing ultra-wide plates using existing thin-plate rolling processes. Ultra-large billet preparation can be achieved with minimal equipment tonnage, making it highly applicable and versatile in engineering applications. The billet preparation process involves recrystallization and softening, eliminating the need for separate heat treatment, resulting in a simple process and low cost.

Description

Technical Field

[0001] This invention application belongs to the technical field of plastic deformation preparation of thin plates in aerospace manufacturing, specifically relating to a billet preparation method for improving the deep drawing processability of hard aluminum alloys, which is particularly suitable for the manufacture of ultra-wide thin-walled, equiaxed fine-grained billets for integral forming of large near-rotation bodies. Background Technology

[0002] It is known that rolled sheet metal exhibits anisotropy. Generally, the strength and plasticity of rolled sheet metal along the fiber direction are significantly better than those perpendicular to the fiber direction, but its shear fatigue strength is significantly lower. The fiber structure of the raw material is inherited by the finished part during subsequent forming processes, especially for near-rotational parts. After deep drawing, the fiber density along the raw material fiber direction increases again, further reducing the shear fatigue performance of the finished product. To address these issues, Chinese patent publication CN117683984A provides a method for improving the azimuth fatigue performance of annular lip parts in aircraft. Its principle involves multiple measures, including directional strengthening and forming force distribution, local thickening extrusion, circumferential bulging, and heat treatment, to sequentially reduce the anisotropy of raw materials and semi-finished products. However, the main drawbacks are as follows: First, it requires repeated deformation and heat treatment, resulting in numerous molds and processes, leading to high manufacturing costs; second, the deformation of the semi-finished product requires directional application of the raw material fibers according to the product shape; and third, due to limitations in the width of domestic sheet metal production, larger parts cannot arbitrarily select the fiber direction as needed.

[0003] Compared with iron-based alloys and titanium alloys, duralumin alloys have significant advantages such as lighter weight and superior thermal conductivity, making them the preferred material for lightweight applications in the international aerospace manufacturing industry. However, the elongation of conventional duralumin alloy sheets is only 40% of that of iron-based alloys, severely limiting the formability of complex parts. Refining the grain size of raw materials can not only reduce the inheritance of anisotropy from raw materials to finished parts and its impact on shear fatigue resistance, but also significantly improve the strength and plasticity of the material in all directions. However, the difficulty of preparing thin sheet metal increases with decreasing sheet thickness and increasing width. According to the material selection range of the national standard GJB2053A, the maximum width of 0.5mm and 4.0mm thick sheets is 1500mm and 2400mm, respectively. Domestic patent publication number CN103343303A provides a method for preparing fine-grained metal materials. The principle is to refine the metal grains by extruding the material to induce large plastic shear strain; however, this disclosed technology can only prepare sample-sized and small-sized bars. Therefore, preparing ultra-thin-walled, equiaxed fine-grained blanks for large near-rotational parts can not only solve the problems of insufficient width of integral forming blanks and poor material forming process, but also avoid defects in the directional mechanical properties of deep-drawn products caused by material fiber inheritance. Summary of the Invention

[0004] This invention addresses the technical problems of existing thin-plate rolling processes, which struggle to produce ultra-wide sheet metal, fail to meet the requirements for integral forming of ultra-large near-rotational thin-walled parts, and suffer from low shear fatigue strength due to the inheritance of inherent fibers from the rolled sheet metal to the near-rotational finished product. The invention proposes a device and method for preparing ultra-wide equiaxed fine-grained thin-plate billets. Utilizing high-speed rotation, high-frequency vibration, and ball-and-rod stirring, along with thickness-direction extrusion, the rotating original billet undergoes a point-by-point kneading effect on both sides of the hot semi-solid, semi-viscous material, resulting in grain breakage, dynamic recrystallization, and superplastic thinning to obtain ultra-wide equiaxed fine-grained thin-plate billets.

[0005] To achieve the aforementioned objectives, the technical solution adopted in this application is as follows:

[0006] An apparatus for preparing ultrawide equiaxed fine-grained thin plates, comprising:

[0007] Workbench;

[0008] A rotary table installed on the workbench is driven to rotate by a motor. A cylindrical anti-rotation insert is embedded in the center of the upper surface of the rotary table, and the anti-rotation insert is provided with a blank positioning hole.

[0009] A support arm, one end of which is fixed to the worktable and the other end is suspended above the rotary table, and a travel groove is provided on the support arm;

[0010] The pressurizing mechanism includes a threaded rod, a threaded connecting rod, a loop sleeve, and a back plate. The loop sleeve is mounted on the support arm, and the back plate is fixedly connected to one side of the loop sleeve. The threaded connecting rod is mounted in the traveling groove, and one end is fixedly connected to the back plate. The threaded rod is threadedly connected to the loop sleeve, and a ball is provided at one end of the threaded rod. By applying radial tension or thrust to the threaded rod, it can reciprocate radially.

[0011] As a further embodiment of the present invention: the threaded rod is provided with an air passage, the upper part of the air passage is a hollow polygonal column, the lower part is a hollow tube, an air inlet pipe is fixed at the top of the hollow polygonal column, a pneumatic rotor is fixed inside the hollow tube, and the rod ball is installed at the lower part of the pneumatic rotor and can rotate relative to the pneumatic rotor.

[0012] As a further aspect of the present invention: the pneumatic rotor has a certain vertical movement space within the hollow tube of the threaded rod. When the pneumatic rotor ventilates, it drives the rod ball to vibrate vertically, and simultaneously drives the rod ball to rotate in the opposite direction to the rotary table.

[0013] As a further aspect of the present invention, two annular magnets are provided above the top surface of the wind turbine, and the magnetic poles of the adjacent surfaces of the two annular magnets are the same.

[0014] As a further embodiment of the present invention: an annular positioning post is provided on the upper surface of the worktable, and a circular three-step positioning post is provided at the center of the lower surface of the rotary table, wherein the diameter of the second step is greater than the diameter of the first step and the third step, and the diameter and depth of the third step are matched with the inner circle of the annular positioning post.

[0015] As a further aspect of the present invention: the depth of the blank positioning hole of the anti-rotation insert of the rotary table is less than the thickness of the anti-rotation insert, and the distance and included angle between any two adjacent positioning holes and the central axis of the rotary table are equal.

[0016] As a further aspect of the present invention: the bottom of the inner circle of the annular positioning column of the worktable and the bottom of the third step of the rotary table are respectively provided with matching hemispherical surfaces; the upper surface of the annular positioning column of the worktable and the lower surface of the second step of the rotary table are respectively provided with a lower semicircular annular groove and an upper semicircular annular groove; the lower semicircular annular groove and the upper semicircular annular groove are connected to each other to form an annular groove; and a number of sliding balls are fixed in the annular groove.

[0017] As a further aspect of the present invention: the lower part of the motor is connected to several fixed plates, and the upper part is provided with a stepped rotating shaft. The stepped rotating shaft is wound around the first step of the rotary table by a belt. The upper surface of the worktable and the motor fixed plate are provided with matching elongated oval adjustment holes. The direction of the adjustment holes is parallel to the line connecting the center axis of the rotary table and the axis of the stepped rotating shaft of the motor.

[0018] A method for preparing an ultrawide equiaxed fine-grained thin plate, comprising the following steps, using the aforementioned thin plate preparation apparatus to prepare an ultrawide thin plate equiaxed fine-grained aluminum alloy target billet:

[0019] 1) Aluminum alloy raw material production: Select a thick plate with appropriate inner and outer diameter and thickness according to the target raw material radius and thickness to make an annular raw material. The inner circle of the raw material is provided with positioning holes that match the position of the anti-rotation insert of the rotating table.

[0020] 2) Pressurization mechanism adjustment: After fixing the thick plate annular original billet to the upper surface of the rotary table with the positioning hole, the threaded connecting rod rotates to make the loop sleeve and threaded rod move radially along the support arm to the predetermined position. Rotate the threaded rod to make the rotating rod ball apply appropriate pressure to the original billet.

[0021] 3) Spinning preparation: Start the motor to drive the rotary table to rotate synchronously with the original billet, and introduce compressed hot air through the air inlet pipe of the thread rod to preheat the original billet. Then perform a test spinning and measure the relationship between the increase in pressure of the thread rod and the thinning amount of the billet during the test spinning.

[0022] 4) First billet spinning: Gradually increase the downward pressure of the threaded rod, and rotate the threaded connecting rod to make the threaded rod move radially in a circular motion. The rotating and vibrating rod ball stirs and compresses the original billet in the thick direction, so that the hot semi-solid and semi-viscous material produces a point-by-point kneading effect on the front side, resulting in grain breaking, dynamic recrystallization, and superplastic thinning to obtain the annular first billet.

[0023] 5) Second blank spinning: Move the threaded rod to the preset starting point, flip the first blank, and spin the outer side of the starting point of the first blank to thin it to the target blank thickness to obtain a ring-shaped second blank with a larger area;

[0024] 6) Spinning of the target billet: The anti-rotation insert is flipped to press the outer edge of the second ring billet tightly, and the inner side of the starting point of the second billet is spun and thinned, so that the inner diameter of the billet is gradually reduced until it is stirred and welded to obtain a solid circular target billet.

[0025] As a further aspect of the present invention: the pressure increment control method of the pressurizing mechanism is to gradually reduce the ultra-thin plate gasket below the hollow polygonal column of the threaded rod. The gasket is made of high-strength hard alloy and its thickness is no more than 0.05mm.

[0026] As a further aspect of the present invention: the temperature of the compressed hot gas introduced into the air inlet pipe of the threaded rod is not higher than 280°C, and the compressed hot gas does not chemically react with the aluminum alloy in an environment below 400°C.

[0027] As a further aspect of the present invention: when the first blank is spun, the threaded rod applies pressure along a radial centrifugal motion from the inner circle of the original blank; when the second blank is spun, the threaded rod applies pressure along a radial centrifugal motion from the starting point; when the target blank is spun, the threaded rod applies pressure along a radial centrifugal motion from the starting point.

[0028] As a further aspect of the present invention: the formula for calculating the thickness and radius of the original billet is as follows: T = T² * R² 2 / (R 2 -r 2 When the first blank is spun, its thickness is calculated using the following formula: T1≤T2+(T-T2)*50%; When the target blank is spun, the radius of the arc corresponding to the starting point is calculated using the following formula: R1 2 =r 2 *T1 / (T1-T2); where the letters T, T1, T2, R, R1, R2, and r refer to the original billet thickness, the first billet thickness, the target billet thickness, the outer radius of the original billet, the radius of the arc at the starting point, the radius of the target billet, and the inner radius of the original billet, respectively.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] 1. This application can achieve the preparation of ultra-wide specification billets with extremely low equipment pressure, and its technology is highly versatile and applicable to engineering applications.

[0031] 2. The billet preparation process of this application is accompanied by recrystallization and softening, and no separate heat treatment is required. The process is simple and the cost is low.

[0032] 3. The billet prepared in this application has uniform planar properties and significantly refined grains, which can improve the plastic forming processability of the material and the mechanical properties of the finished product.

[0033] The present application will be further described below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0034] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the embodiments of the invention to explain the invention and do not constitute a limitation thereof.

[0035] In the attached diagram:

[0036] Figure 1 This is a schematic diagram of the overall structure and principle of the preparation device in this application;

[0037] Figure 2 This is a side-view top view of the rotating stage structure of the fabrication apparatus of this application;

[0038] Figure 3 This is a schematic diagram of the worktable structure of the preparation apparatus of this application;

[0039] Figure 4 This is a side-view, bottom-view structural diagram of the rotary table of the fabrication apparatus of this application;

[0040] Figure 5 This is a schematic cross-sectional view of the fabrication device along the support arm direction.

[0041] Figure 6 This is a schematic diagram of the pressurization mechanism of the preparation apparatus in this application;

[0042] Figure 7 This is a schematic diagram illustrating the scaled-up principle of preparing the first billet from the original billet used in this application.

[0043] Figure 8 This is a schematic diagram illustrating the scaled-up principle of preparing the target billet for the second billet in this application.

[0044] The following are the labels in the attached diagram: 1. Worktable, 2. Rotary table, 3. Motor, 4. Support arm, 5. Pressurizing mechanism, 6. Annular positioning column, 7. Anti-rotation insert, 8. Positioning hole, 9. First step, 10. Second step, 11. Third step, 12. Fixed plate, 13. Rotating shaft, 14. Belt, 15. Threaded rod, 16. Threaded connecting rod, 17. U-shaped sliding sleeve, 18. Back plate, 19. Air inlet pipe, 20. Pneumatic rotor, 21. Rod ball, 22. Adjustment hole, 23. Central shaft, 24. Hemispherical surface, 25. Annular groove, 26. Sliding ball, 27. Annular magnet, 28. Original blank, 29. First blank, 30. Second blank, 31. Target blank, 32. Starting point, 33. Shim. Detailed Implementation

[0045] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0046] First, we introduce the technical solution of the ultra-wide equiaxial fine-grained thin plate preparation device of this application.

[0047] See attached document Figure 1 To be continued Figure 8 The preparation apparatus includes a worktable 1, a rotary table 2, a motor 3, a support arm 4, and a movable pressurizing mechanism 5 fixed to the support arm. The worktable 1 is fixed to the ground by support legs, and an annular positioning post 6 is provided on the upper surface of the worktable 1. A cylindrical anti-rotation insert 7 is embedded in the center of the upper surface of the rotary table 2, and a blank positioning hole 8 is provided on the anti-rotation insert 7. A circular three-step positioning post is provided in the center of the lower surface of the rotary table 2, and the diameter of the second step 10 is larger than the diameters of the first step 9 and the third step 11. The diameter and depth of the third step 11 match the inner circle of the annular positioning post 6 of the worktable. The lower part of the motor 3 is connected to several fixing plates 12, and the upper part is provided with a stepped rotating shaft 13. The rotating shaft 13 is wound around the first step 9 of the rotary table by a belt 14. One end of the support arm 4 is fixed to the worktable 1, and the other end is suspended above the rotary table 2. The pressurizing mechanism 5 is provided with a threaded rod 15, a threaded connecting rod 16, a spiral sleeve 17, and a back plate 18. The threaded rod 15 passes through the spiral sleeve to control vertical displacement; the threaded connecting rod 16 passes through the support arm and is connected to the back plate 18, applying radial tension or thrust to the threaded rod 15 to make it reciprocate slowly and uniformly along the radial direction.

[0048] Further, refer to the appendix Figure 1 Appendix Figure 2In order to refine the microstructure of the target billet 31 by double-sided spinning of the thick plate raw billet 28, and to facilitate the anti-rotation insert 7 and billet flipping and positioning during the billet preparation process, the depth of the billet positioning hole 8 of the anti-rotation insert 7 of the rotary table 2 is less than the thickness of the anti-rotation insert 7, and the distance and included angle between any two adjacent positioning holes 8 and the central axis 23 of the rotary table are equal.

[0049] Further, refer to the appendix Figure 1 Appendix Figure 3 In order to facilitate the adjustment of the tension of the belt 14 during use, the upper surface of the worktable 1 and the motor fixing plate are provided with matching elongated adjustment holes 22. The direction of the adjustment holes 22 is parallel to the line connecting the center axis of the rotary table 23 and the axis of the motor rotation shaft 13.

[0050] Further, refer to the appendix Figure 1 Appendix Figure 5 To prevent the rotary table 2 from rotating and swinging at high speed and to reduce friction between the rotary table 2 and the annular positioning post 6 of the worktable, the bottom of the inner circle of the annular positioning post 6 of the worktable and the bottom of the third step 11 of the rotary table are respectively provided with matching hemispherical surfaces 24.

[0051] Furthermore, refer to the appendix. Figure 1 Appendix Figure 3 To be continued Figure 5 In order to further reduce the frictional resistance of the rotary table 2, the upper surface of the annular positioning column 6 of the worktable 1 and the lower surface of the second step 10 of the rotary table are respectively provided with a lower semi-circular annular groove and an upper semi-circular annular groove. The lower semi-circular annular groove and the upper semi-circular annular groove are connected to each other to form a closed annular groove 25. A number of sliding balls 26 are provided in the annular groove 25.

[0052] Further, refer to the appendix Figure 1 Appendix Figure 7 Appendix Figure 8 In order to disrupt the fiber structure of the raw materials by stirring, the upper part of the threaded rod 15 of the pressurizing mechanism is a hollow polygonal column, and the lower part is a hollow tube; an air inlet pipe 19 is fixed at the top of the hollow polygonal column, and a pneumatic rotor 20 is installed inside the hollow tube, with a rotating ball 21 installed at the lower part of the pneumatic rotor. The pneumatic rotor 20 has a certain vertical movement space in the hollow tube of the threaded rod 15.

[0053] Furthermore, refer to the appendix. Figure 7 Appendix Figure 8 In order to increase the mixing effect of the rod ball 21 on the billet and reduce the friction of the rod ball 21 on the billet, when the pneumatic rotor 20 is ventilating, the pneumatic rotor drives the rod ball 21 to vibrate vertically and at the same time drives the rod ball 21 to rotate in the opposite direction to the rotary table 2.

[0054] Furthermore, refer to the appendix Figure 7 Appendix Figure 8The top surface of the wind-driven rotor 20 is also fixed with two ring magnets 27. The magnetic poles of the adjacent surfaces of the two ring magnets 27 are the same. The purpose is to use the magnetic repulsion force of the same pole at close range to ensure that the pressure of the rod ball 21 on the billet is sufficient, while leaving vibration space to reduce the friction of the rod ball 21 on the billet.

[0055] Next, we will introduce the method of using the thin plate preparation apparatus of this application to prepare equiaxed fine-grained thin plates.

[0056] Ultra-wide thin-plate equiaxed fine-grained aluminum alloy sheets were fabricated using the aforementioned thin-plate preparation apparatus, as shown in the attached figure. Figure 1 Appendix Figure 5 Appendix Figure 7 Appendix Figure 8 It mainly includes the following steps:

[0057] 1) Aluminum alloy raw material production: Select a thick plate ring raw material 28 with appropriate inner and outer diameters and thickness according to the radius and thickness of the target raw material 31. The inner circle of the raw material 28 is provided with positioning holes 8 that match the position of the anti-rotation insert 7 of the rotating table.

[0058] 2) Pressurization mechanism adjustment: After the thick plate annular original billet 28 is fixed on the upper surface of the rotary table 2 with the positioning hole 8, the threaded connecting rod 16 rotates to make the loop sleeve 17 and the threaded rod 15 move radially along the support arm 4 to the predetermined position. The threaded rod 15 is rotated so that the rotating rod ball 21 applies appropriate pressure to the original billet 28.

[0059] 3) Spinning preparation: Start motor 3 to drive the rotary table 2 to rotate synchronously with the original billet 28, and introduce compressed hot air through the air inlet pipe 19 of the threaded rod 15 to preheat the original billet 28 and then perform a spin test. Measure the relationship between the increase in pressure of the threaded rod 15 and the amount of thinning of the billet during the spin test.

[0060] 4) First billet spinning: Gradually increase the downward pressure of the threaded rod 15, and rotate the threaded connecting rod 16 to make the threaded rod 15 move radially in a circular motion. The rotating and vibrating rod ball 21 stirs and compresses the original billet 28 in the thick direction, so that the hot semi-solid and semi-viscous material produces a point-by-point kneading effect on the front side, resulting in grain breaking, dynamic recrystallization, and superplastic thinning to obtain the annular first billet 29.

[0061] 5) Second blank spinning: Move the threaded rod 15 to the preset starting point 32, flip the first blank 29, and spin the outer side of the first blank starting point 32 to thin it to the thickness of the target blank 31, so as to obtain a larger annular second blank 30.

[0062] 6) Spinning of target billet: Flip the anti-rotation insert 7 to press the outer edge of the annular second billet 30, and spin the inner side of the starting point 32 of the second billet to thin it, so that the inner diameter of the billet is gradually reduced until it is stirred and welded to obtain a solid circular target billet 31.

[0063] Furthermore, to reduce equipment pressure requirements and frictional resistance, the material needs to be appropriately heated, but the temperature must be controlled appropriately. During the spinning process from the original billet 28 to the target billet 31, compressed hot gas is introduced through the air inlet pipe 19 of the threaded rod. For aluminum alloys, the temperature of the compressed hot gas should not exceed 280℃. The purpose is to refine the grains through dynamic recrystallization of the metal under strong deformation. To reduce gas costs, the compressed hot gas does not chemically react with the aluminum alloy at 400℃. For aluminum alloys, this gas can be a low-cost gas with inert chemical properties, such as nitrogen or carbon dioxide. It should be emphasized that for other metals, the temperature and type of gas used should be determined according to the metal deformation recrystallization temperature and specific chemical properties.

[0064] Further, refer to the appendix Figure 8 To improve the wall thickness accuracy of the target blank 31, the pressure increment control method of the pressurizing mechanism 5 is as follows: gradually reduce the ultra-thin plate shim 33 below the hollow polygonal column of the threaded rod 15. The shim 33 is made of high-strength hard alloy and its thickness is no more than 0.05mm. It should be noted that the wall thickness accuracy mainly depends on the pressure increment of the rod ball 21 during the final spinning process. As long as it does not affect factors such as friction, the pressure of the rod ball 21 can be appropriately increased before the final spinning process to improve efficiency.

[0065] Further, refer to the appendix Figure 5 Appendix Figure 7 Appendix Figure 8 To ensure proper operation, the thinning and spinning process essentially involves gradually rolling the thicker inner material outwards to increase the surface area. However, the ultimate goal of this application is to prepare a solid target blank 31. When spinning the first blank 29, the threaded rod 15 applies pressure along a radial centrifugal trajectory from the inner circle of the original blank 28. When spinning the second blank 30, the threaded rod 15 applies pressure along a radial centrifugal trajectory from the starting point 32. When spinning the target blank 31, the threaded rod 15 applies pressure along a radial centripetal trajectory from the starting point 32.

[0066] Furthermore, in order to minimize raw material waste, the formula for calculating the thickness and radius of the original blank 28 is as follows: T=T2*R2 2 / (R 2 -r 2The limit size of the target billet 31 can be calculated based on the known specifications of the raw materials. Conversely, the original billet 28 specifications can be calculated based on the actual requirements of the target billet 31 size. The principle is based on the principle that the volume or weight remains unchanged before and after forming. To ensure uniform microstructure and properties on both sides of the target billet 31, the thickness calculation formula for the first billet 29 during spinning is as follows: T1≤T2+(T-T2)*50%. The purpose is to refine the grains by increasing the kneading effect of the material through double-sided stirring and extrusion. To achieve the purpose of central stirring and welding of the target billet 31, and to avoid excessive material accumulation, the radius calculation formula for the arc corresponding to the starting point 32 during spinning of the target billet 31 is as follows: R1 2 =r 2 *T1 / (T1-T2); where the letters T, T1, T2, R, R1, R2, and r refer to the thickness of the original billet 28, the thickness of the first billet 29, the thickness of the target billet 31, the outer radius of the original billet 28, the radius of the arc of the starting point 32, the radius of the target billet 31, and the inner radius of the original billet 28, respectively.

[0067] Thus, the objective of this invention has been achieved.

[0068] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An apparatus for preparing ultrawide equiaxed fine-grained thin plates, characterized in that, include: Workbench; A rotary table installed on the workbench is driven to rotate by a motor. A cylindrical anti-rotation insert is embedded in the center of the upper surface of the rotary table, and the anti-rotation insert is provided with a blank positioning hole. A support arm, one end of which is fixed to the worktable and the other end is suspended above the rotary table, and a travel groove is provided on the support arm; The pressurizing mechanism includes a threaded rod, a threaded connecting rod, a U-shaped sliding sleeve, and a back plate. The U-shaped sliding sleeve is mounted on the support arm, and the back plate is fixedly connected to one side of the U-shaped sliding sleeve. The threaded connecting rod is mounted in the traveling groove, and one end is fixedly connected to the back plate. The threaded rod is threadedly connected to the U-shaped sliding sleeve. A ball is provided at one end of the threaded rod. By applying radial tension or thrust to the threaded rod, it can reciprocate radially. An air passage is provided inside the threaded rod. The upper part of the air passage is a hollow polygonal column, and the lower part is a hollow tube. An air inlet pipe is fixed at the top of the hollow polygonal column, and a pneumatic rotor is fixed inside the hollow tube. The ball is mounted below the pneumatic rotor and can rotate relative to the pneumatic rotor. The pneumatic rotor has a certain vertical movement space in the hollow tube of the threaded rod.

2. The apparatus for preparing ultra-wide equiaxed fine-grained thin plates according to claim 1, characterized in that, Two annular magnets are also provided above the top surface of the wind turbine, and the magnetic poles of the adjacent surfaces of the two annular magnets are the same.

3. The apparatus for preparing ultra-wide equiaxed fine-grained thin plates according to claim 1 or 2, characterized in that, An annular positioning post is provided on the upper surface of the worktable, and a circular three-step positioning post is provided at the center of the lower surface of the rotary table. The diameter of the second step is larger than the diameters of the first and third steps, and the diameter and depth of the third step match the inner circle of the annular positioning post.

4. The apparatus for preparing ultra-wide equiaxed fine-grained thin plates according to claim 3, characterized in that, The blank positioning hole depth of the anti-rotation insert of the rotary table is less than the thickness of the anti-rotation insert, and the distance and included angle between any two adjacent positioning holes and the central axis of the rotary table are equal.

5. The apparatus for preparing ultra-wide equiaxed fine-grained thin plates according to claim 4, characterized in that, The bottom of the inner circle of the worktable's annular positioning column and the bottom of the third step of the rotary table are respectively provided with matching hemispherical surfaces. The upper surface of the worktable's annular positioning column and the lower surface of the second step of the rotary table are respectively provided with a lower semicircular annular groove and an upper semicircular annular groove. The lower semicircular annular groove and the upper semicircular annular groove are connected to each other to form an annular groove. Several sliding balls are fixed in the annular groove.

6. The apparatus for preparing ultra-wide equiaxed fine-grained thin plates according to claim 5, characterized in that, The motor has several fixed plates connected to its lower part and a stepped rotating shaft on its upper part. The stepped rotating shaft is wound around the first step of the rotary table by a belt. The upper surface of the worktable and the motor fixed plate are provided with matching elongated oval adjustment holes. The direction of the adjustment holes is parallel to the line connecting the center axis of the rotary table and the axis of the motor stepped rotating shaft.

7. A method for preparing an ultra-wide equiaxed fine-grained thin plate, comprising using the ultra-wide equiaxed fine-grained thin plate preparation apparatus according to any one of claims 1 to 6 to prepare an ultra-wide thin plate equiaxed fine-grained aluminum alloy target billet, characterized in that, Includes the following steps: 1) Aluminum alloy raw material production: Select a thick plate with appropriate inner and outer diameter and thickness according to the target raw material radius and thickness to make an annular raw material. The inner circle of the raw material is provided with positioning holes that match the position of the anti-rotation insert of the rotating table. 2) Pressurization mechanism adjustment: After fixing the thick plate annular original billet to the upper surface of the rotary table with the positioning hole, the threaded connecting rod rotates to make the loop sleeve and threaded rod move radially along the support arm to the predetermined position. Rotate the threaded rod to make the rotating rod ball apply appropriate pressure to the original billet. 3) Spinning preparation: Start the motor to drive the rotary table to rotate synchronously with the original billet, and introduce compressed hot air through the air inlet pipe of the thread rod to preheat the original billet. Then perform a test spinning and measure the relationship between the increase in pressure of the thread rod and the thinning amount of the billet during the test spinning. 4) First billet spinning: Gradually increase the downward pressure of the threaded rod, and rotate the threaded connecting rod to make the threaded rod move radially in a circular motion. The rotating and vibrating rod ball stirs and compresses the original billet in the thick direction, so that the hot semi-solid and semi-viscous material produces a point-by-point kneading effect on the front side, resulting in grain breaking, dynamic recrystallization, and superplastic thinning to obtain the annular first billet. 5) Second blank spinning: Move the threaded rod to the preset starting point, flip the first blank, and spin the outer side of the starting point of the first blank to thin it to the target blank thickness to obtain a ring-shaped second blank with a larger area; 6) Spinning of the target billet: The anti-rotation insert is flipped to press the outer edge of the second ring billet tightly, and the inner side of the starting point of the second billet is spun and thinned, so that the inner diameter of the billet is gradually reduced until it is stirred and welded to obtain a solid circular target billet.

8. The method for preparing an ultrawide equiaxed fine-grained thin plate according to claim 7, characterized in that, The pressure increment control method of the pressurization mechanism is as follows: gradually reduce the ultra-thin plate gasket below the hollow polygonal column of the threaded rod. The gasket is made of high-strength hard alloy and its thickness is no more than 0.05mm.

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