Shape and property collaborative manufacturing method of integral ribbed panel

Abstract

The invention relates to the technical field of metal plate forming, in particular to a shape collaborative manufacturing method of a ribbed integral wallboard, which comprises the following steps: manufacturing a cylindrical ribbed wallboard slab by adopting an extrusion mode, and splitting the cylindrical ribbed wallboard slab along the axial direction to obtain a large-curvature wide slab; and carrying out heat treatment forming on the large-curvature wide plate blank by utilizing a creep age forming process to obtain the integral ribbed panel. The shape collaborative manufacturing method of the ribbed integral wall plate aims to solve the problem that the structure property and the shape precision of the ribbed integral wall plate are difficult to meet the use requirements at the same time.

Description

Technical Field

[0001] The invention relates to the technical field of sheet metal forming, and in particular to a method for collaboratively manufacturing the shape of a ribbed integral wall panel. Background Art

[0002] The integral wall panel is an important component of the aircraft's aerodynamic shape, and is also the main load-bearing component of the wing, fuselage, etc. The wall panels of the aircraft are usually assembled by riveting, gluing or spot welding with skin and longitudinal and transverse reinforcement parts. The stiffness, strength and sealing of this assembled wall panel are poor. Later, the integral wall panel was gradually replaced by the assembled wall panel, that is, there is no mechanical connection between the skin, reinforcement boss, depression, ribs and other structural elements of the wall panel. Large integral ribbed wall panels are mainly used for aircraft wings and fuselage, as well as important parts such as floors and fuel tanks. Compared with the traditional riveted combined wall panel structure, the ribbed integral wall panel structure has a high integrity, which can greatly improve the structural efficiency, reduce the number of connectors and the workload of riveting assembly, and effectively reduce the weight of the structure. Compared with the riveted combined wall panel, it can achieve a weight reduction of 10% to 30%. Therefore, the ribbed integral wall panel structure has been widely used in aerodynamic shape parts of aerospace vehicles, such as wing wall panels, fuselage wall panels, engine intake and exhaust duct wall panels, and launch vehicle body wall panels. The use of lightweight, high-strength materials and large, thin-walled, integrated complex structures has become an inevitable choice. In order to meet the above requirements, under the premise of maintaining the original structural strength, the components are generally designed to be thin-walled and highly reinforced, and reinforced thin-walled components are an important and typical representative.

[0003] This overall ribbed structure is reasonably designed, not only has a light overall mass and occupies a small space, but also can withstand large loads and effectively play a supporting, protective and connecting role. Therefore, in the aerospace field, such as the integral fuselage panels of aircraft and the integral panels of the central wing and outer wing of aircraft, the structural combination of high ribs + thin webs can effectively achieve reliability and lightness.

[0004] Therefore, the inventor provides a method for collaboratively manufacturing the shape of ribbed integral wall panels. Summary of the invention

[0005] (1) Technical issues to be solved

[0006] The embodiment of the present invention provides a method for co-manufacturing a ribbed integral wall panel in terms of shape and properties, which solves the technical problem that the structural performance and shape accuracy of the ribbed integral wall panel are difficult to meet the use requirements at the same time.

[0007] (2) Technical solution

[0008] The present invention provides a method for collaboratively manufacturing a ribbed integral wall panel, comprising the following steps:

[0009] The cylindrical ribbed wall panel blank is manufactured by extrusion, and the cylindrical ribbed wall panel blank is cut axially to obtain a wide-width slab with a large curvature;

[0010] The large curvature and wide width slab is heat treated and formed by using a creep aging forming process to obtain a ribbed integral wall panel.

[0011] Furthermore, the method of manufacturing the cylindrical ribbed wall panel blank by extrusion is specifically as follows:

[0012] The blank is extruded into a cylindrical part on an extruder with the same preset rib structure size and wall thickness as the target part.

[0013] Furthermore, the cylindrical ribbed wall panel blank is cut open along the axial direction to obtain a wide-width slab with a large curvature, specifically:

[0014] According to the outer dimensions of the target part, the cylindrical part after extrusion is cut open along the axial direction to form the large curvature and wide width slab.

[0015] Furthermore, the creep aging forming process is used to heat treat the large curvature and wide width slab to obtain the ribbed integral wall panel, which specifically includes the following steps:

[0016] Placing the large curvature and wide width slab on the molding die surface;

[0017] The finite element method is used to calculate the pressure required for the outer surface of the part to completely fit the molding surface of the forming die;

[0018] The large-curvature and wide-width slab and the forming mold are integrally packaged and vacuumized;

[0019] Keeping the vacuum state, placing the large curvature and wide width slab and the forming mold into the autoclave;

[0020] The autoclave is heated, and when the large curvature and wide width slab reaches a first preset temperature, the temperature is kept for a first preset time, and the large curvature and wide width slab is kept in a vacuum state; when the first preset temperature is reached, a first pressure is applied to the surface of the part;

[0021] When the first preset time is reached, the temperature is continuously raised to the second preset temperature and then kept warm for the second preset time, and a second pressure is applied to the surface of the part so that the outer surface of the large curvature and wide width slab is completely fitted with the inner surface of the forming mold;

[0022] When the second preset time is reached, the temperature starts to drop, and when the mold temperature drops to the third preset temperature, the pressure is unloaded to obtain the ribbed integral wall panel.

[0023] Furthermore, the curvature radius R of the forming die is m1=1.2R 挤压 ~1.5R 挤压 , where R 挤压 is the radius of the extrusion die during extrusion.

[0024] Furthermore, the forming die profile is a die profile calculated by a creep aging forming method to compensate for the springback amount.

[0025] Furthermore, the first pressure P1 is 0.2P-0.5P, wherein P is the pressure required for the outer surface of the large curvature and wide width slab to be completely fitted with the molding surface of the forming mold calculated by using the finite element method.

[0026] Furthermore, the second pressure P2 is P.

[0027] Furthermore, before the cylindrical ribbed wall panel blank is manufactured by extrusion, the method further comprises:

[0028] The aluminum alloy billet and the extrusion die are heated to the aluminum alloy solution heat treatment temperature and kept at this temperature for a preset time.

[0029] Furthermore, the method of manufacturing the cylindrical ribbed wall panel blank by extrusion is specifically as follows:

[0030] During extrusion, the temperature of the extrusion die and the extrusion barrel is greater than the solution heat treatment temperature of the aluminum alloy, and the extrusion speed of the extrusion barrel is 0.2-0.5 mm / s.

[0031] (3) Beneficial effects

[0032] In summary, the present invention adopts extrusion to prepare the initial ribbed structural parts, which reduces the cutting of metal streamlines at the high-ribbed structural position due to machining, resulting in a reduction in the strength of the component; the cylindrical ribbed wall panel blank is directly manufactured by extrusion, and the circumference is changed to a width, so that a large-width integral wall panel can be obtained, reducing the manufacturing cost and cycle. At the same time, creep aging forming can improve the forming limit and forming accuracy of the overall wall panel on the premise of obtaining good comprehensive performance, and can also effectively avoid defects in the thin skin area, improve the uniformity of the component's organizational performance, ensure the integrated forming / forming manufacturing of complex wall panel components, effectively improve the shape accuracy of the parts and further increase the service life of the wall panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments of the present invention are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0034] Figure 1It is a schematic flow chart of a method for collaboratively manufacturing a ribbed integral wall panel provided by an embodiment of the present invention;

[0035] Figure 2 This is a schematic diagram of a shape-coordinated manufacturing process of a ribbed integral wall panel provided in Example 1 of the present invention;

[0036] Figure 3 A creep aging forming temperature-time diagram based on an extruded wall panel is provided in an embodiment of the present invention.

[0037] In the figure:

[0038] 1-blank; 2-cylindrical part; 3-preformed wall panel part; 4-forming mold; 5-ribbed integral wall panel. DETAILED DESCRIPTION

[0039] The following is a further detailed description of the embodiments of the present invention in conjunction with the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to exemplarily illustrate the principles of the present invention, but cannot be used to limit the scope of the present invention, that is, the present invention is not limited to the described embodiments, and covers any modification, replacement and improvement of parts, components and connection modes without departing from the spirit of the present invention.

[0040] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0041] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of the present invention are conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. These are merely for the convenience of describing the present invention 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 the present invention.

[0042] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "setting" and "installation" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0043] Compared with the traditional integral wall panel component forming technology, creep aging forming technology is a technology developed for forming complex-shaped parts, especially integral wall panel parts, that is, a forming method that uses the creep characteristics of metal to perform forming and aging simultaneously. Compared with the traditional forming process, this forming method improves the material strength, reduces residual stress, enhances stress corrosion resistance, and extends the service life of parts. It is suitable for forming integral ribs of age-hardened alloys and integral wall panel components with complex shapes and structures with variable thickness and large curvature. This technology is considered to be one of the particularly important metal forming processes for the next generation of large aircraft. With the increasingly urgent demand for large high-performance aircraft in military and civil aviation, this forming process will play its unique advantages in the manufacture of large and complex integral wall panels. It has broad application prospects in the development of large aircraft projects in my country.

[0044] Figure 1 is a flow chart of a method for collaboratively manufacturing a ribbed integral wall panel according to an embodiment of the present invention, see Figure 1 , the method may include the following steps:

[0045] S100, manufacturing a cylindrical ribbed wall panel blank by extrusion, and cutting the cylindrical ribbed wall panel blank axially to obtain a wide-width blank with a large curvature.

[0046] Specifically, the blank is extruded into a cylindrical part with the preset rib structure size and wall thickness of the target part on an extruder, and the cylindrical part after extrusion is cut along the axial direction according to the outer dimensions of the target part to form a large curvature and wide width blank. Figure 3 As shown, in stage A, during extrusion, the temperature of the extrusion die and the extrusion barrel on the extruder is greater than the solution heat treatment temperature T1 of the aluminum alloy, and the extrusion speed of the extrusion barrel is 0.2-0.5 mm / s.

[0047] Furthermore, before step S100, the process also includes: heating the aluminum alloy billet and the extrusion die to the aluminum alloy solid solution heat treatment temperature, and keeping the temperature for a preset time, which is 3 to 5 hours.

[0048] S200, using creep aging forming process to heat treat and form large curvature and wide width slab to obtain ribbed integral wall panel.

[0049] Specifically, step S200 may include the following steps:

[0050] S201, placing a large curvature and wide slab on a forming die surface;

[0051] S202, using the finite element method to calculate the pressure required for the outer surface of the part to fit completely with the molding die surface;

[0052] S203, integrally packaging the large curvature and wide width slab and the forming mold, and performing vacuuming;

[0053] S204, maintaining the vacuum state, placing the large curvature wide slab and the forming mold into the autoclave;

[0054] S205, the autoclave is heated, and when the large curvature and wide width slab reaches the first preset temperature T2, it is kept warm for the first preset time h1, and the large curvature and wide width slab is kept in a vacuum state; when the first preset temperature T2 is reached, a first pressure is applied to the surface of the part;

[0055] S206, when the first preset time is reached, the temperature is continuously raised to the second preset temperature T3 and then kept warm for the second preset time h2, and a second pressure is applied to the surface of the part so that the outer surface of the large curvature and wide width slab is completely fitted with the inner surface of the forming mold;

[0056] S207, when the second preset time h2 is reached, the temperature starts to be lowered, and when the mold temperature drops to the third preset temperature, the pressure is unloaded to obtain a ribbed integral wall panel.

[0057] The manufacturing process of this conformal collaborative manufacturing method is as follows Figure 2 As shown, the blank 1 is formed into a cylindrical part 2 after extrusion processing, and the cylindrical part 2 is cut along its axis to obtain a preformed wall panel part 3, and then the preformed wall panel part 3 is placed on the mold surface of the forming mold 4 and subjected to creep aging forming to finally obtain an integral ribbed wall panel 5.

[0058] In the above embodiment, creep aging forming process is adopted to shape and precisely form the shape of the extruded cylindrical wall panel, thereby reducing the forming cycle of the parts. Figure 3 As shown, in stage B, the autoclave is heated, and when the large curvature and wide width slab reaches the first preset temperature T2, it is kept warm for the first preset time h1, and the large curvature and wide width slab is kept in a vacuum state; when the first preset temperature T2 is reached, the first pressure is applied to the surface of the part; when the first preset time is reached, the temperature continues to rise to the second preset temperature T3 and then is kept warm for the second preset time h2, and the second pressure is applied to the surface of the part, so that the outer surface of the large curvature and wide width slab is completely fitted with the inner surface of the forming mold; when the second preset time h2 is reached, the temperature begins to drop. The different pressures of the segmented aging heat treatment are combined with different insulation times and insulation temperatures to achieve coordinated control of the shape of the parts. The creep aging forming adopts vacuum pressure loading, the pressure distribution is uniform, and there is no stress concentration point after forming; at the same time, the creep aging forming is used as a heat treatment process, which can improve the strength and comprehensive performance of the parts, reduce the residual stress generated by the extrusion process during the aging cycle, and make the part structure performance more uniform and stable.

[0059] In summary, the present invention adopts extrusion to prepare the initial ribbed structural parts and then performs creep aging forming, which can effectively improve the overall forming limit of the parts, reduce deformation resistance, and reduce forming defects. Through the present invention, parts with internal structure (certain rib structure size and wall thickness) and appearance can be directly obtained, without the need to first prepare a pre-stretched thick plate and then mechanically remove the material to obtain the internal structure of the wall panel (rib structure and wall thickness), and finally perform part shape forming, which greatly improves material utilization, effectively reduces costs, and shortens the preparation cycle.

[0060] Furthermore, in step S201, the curvature radius R of the forming mold m1 =1.2R 挤压 ~1.5R 挤压 , where R 挤压 is the radius of the extrusion die during extrusion. The first pressure P1 is 0.2P-0.5P, and the second pressure P2 is P, where P is the pressure required for the outer surface of the large curvature and wide width slab to completely fit the forming die surface calculated by the finite element method. The third preset temperature can be 50°C.

[0061] As an optional embodiment, the forming die profile is a die profile calculated by a creep aging forming method to compensate for the springback amount.

[0062] Example 1

[0063] In this embodiment 1, an aluminum alloy 7050 wall panel structure is used as a manufacturing object. The part is an integral wall panel. The manufacturing method of the present invention is used to form the part. The specific steps are as follows:

[0064] (1) Heat the 7050 aluminum alloy billet and the extrusion die to a heat treatment temperature of 480°C and keep it at that temperature for 3 hours;

[0065] (2) Extrusion forming: The blank in step (1) is extruded into a cylindrical part with a certain rib structure size and wall thickness required by the target part (rib height is 30 mm, skin thickness is 8 mm, wall panel length is 1500 mm) on an extruder; during extrusion, the die temperature is 487°C ± 5°C, the extrusion barrel temperature is 485°C ± 5°C, and the extrusion barrel extrusion speed is 0.3 mm / s; during extrusion, the die radius R 挤压 =800mm;

[0066] (3) Cutting the cylindrical part after extrusion along the axis according to the outer dimensions of the target part to form a preformed wall panel part, wherein the curvature radius of the target part is 3000 mm;

[0067] (4) Place the preformed panel part on a forming die with a curvature radius R m1 =1200mm;

[0068] (5) The preformed wall panel parts and the forming mold are packaged as a whole with breathable felt and vacuum bags, and then placed in an autoclave as a whole. The autoclave is heated up. When the preformed wall panel parts reach a temperature of 120°C ± 5°C, they are kept warm for 8 hours. At this time, the pressurization system is turned on to apply a pressure P1 = 0.1 MPa to the surface of the parts;

[0069] (6) When the wall panel parts reach the holding time of 8h, continue to heat up to 160℃±5℃ and then keep warm for 20h; at this time, start the pressurization system to apply pressure P2=0.3MPa to the surface of the parts, so that the outer surface of the preformed wall panel parts and the inner surface of the forming mold are completely fitted; when the holding time is reached, start to cool down;

[0070] (7) When the temperature of the forming mold drops below 50°C, unload the pressure, open the furnace door and take out the ribbed integral wall panel;

[0071] (8) The gap between the outer film and the film of the formed ribbed integral wall panel is ≤1mm, and the straightness deviation is ≤±1mm; the specimens are cut along the axial direction to measure the room temperature tensile mechanical properties: tensile strength R m =530MPa, yield strength R p0.2 =450MPa, elongation after break A=10%, meeting the design requirements.

[0072] Example 2

[0073] In this embodiment 2, an aluminum alloy 6061 wall panel structure is used as a manufacturing object. The part is an integral wall panel. The manufacturing method of the present invention is used to form the part. The specific steps are as follows:

[0074] (1) Heat the 6061 aluminum alloy billet and the extrusion die to a heat treatment temperature of 510°C to 530°C and keep it for 4 hours;

[0075] (2) Extrusion forming: The blank in step (1) is extruded into a cylindrical part with a certain rib structure size and wall thickness required by the target part (rib height is 15 mm, skin thickness is 5 mm, wall length is 1000 mm); during extrusion, the die temperature is 520°C ± 5°C, the extrusion barrel temperature is 525°C ± 5°C, and the extrusion barrel extrusion speed is 0.25 mm / s; during extrusion, the die radius R 挤压 =600mm;

[0076] (3) Cutting the cylindrical part after extrusion along the axis according to the outer dimensions of the target part to form a preformed wall panel part, wherein the curvature radius of the target part is 2000 mm;

[0077] (4) Place the preformed panel part on a forming die with a curvature radius R m1=900mm;

[0078] (5) The preformed wall panel parts and the forming mold are packaged as a whole with breathable felt and vacuum bags, and then placed in an autoclave as a whole. The autoclave is heated up. When the preformed wall panel parts reach a temperature of 110°C ± 5°C, they are kept warm for 6 hours. At this time, the pressurization system is turned on to apply a pressure P1 = 0.1 MPa to the surface of the parts;

[0079] (6) When the wall panel parts reach the holding time of 6h, continue to heat up to 150℃±5℃ and then keep warm for 10h; at this time, start the pressurization system to apply pressure P2=0.2MPa to the surface of the parts, so that the outer surface of the preformed wall panel parts and the inner surface of the forming mold are completely fitted; when the holding time is reached, start to cool down;

[0080] (7) When the temperature of the forming mold drops below 50°C, unload the pressure, open the furnace door and take out the ribbed integral wall panel;

[0081] (8) The gap between the outer film and the film of the formed ribbed integral wall panel is ≤1mm, and the straightness deviation is ≤±1mm; the specimens are cut along the axial direction to measure the room temperature tensile mechanical properties: tensile strength R m =325MPa, yield strength R p0.2 =256MPa, elongation after break A=8%, meeting the design requirements.

[0082] It should be clear that the various embodiments in this specification are described in a progressive manner, and the same or similar parts between the various embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. The present invention is not limited to the specific steps and structures described above and shown in the figures. In addition, for the sake of brevity, a detailed description of known methods and technologies is omitted here.

[0083] The above are only embodiments of the present application and are not limited to the present application. For those skilled in the art, the present application may have various changes and variations without departing from the scope of the present invention. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A method for collaboratively manufacturing a ribbed integral wall panel, characterized in that: The method comprises the following steps: The cylindrical ribbed wall panel blank is manufactured by extrusion, and the cylindrical ribbed wall panel blank is cut axially to obtain a wide-width slab with a large curvature; The large curvature and wide width slab is heat treated and formed by using a creep aging forming process to obtain a ribbed integral wall panel.

2. The method for collaboratively manufacturing the ribbed integral wall panel according to claim 1, characterized in that: The method of manufacturing the cylindrical ribbed wall panel blank by extrusion is specifically as follows: The blank is extruded into a cylindrical part on an extruder with the same preset rib structure size and wall thickness as the target part.

3. The method for collaboratively manufacturing the ribbed integral wall panel according to claim 2, characterized in that: The step of axially splitting the cylindrical ribbed wall panel blank to obtain a wide-width slab with a large curvature is specifically as follows: According to the outer dimensions of the target part, the cylindrical part after extrusion is cut open along the axial direction to form the large curvature and wide width slab.

4. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 1, characterized in that: The method of heat treating and forming the large curvature and wide width slab by using a creep aging forming process to obtain a ribbed integral wall panel specifically includes the following steps: Placing the large curvature and wide width slab on the molding die surface; The finite element method is used to calculate the pressure required for the outer surface of the part to completely fit the molding surface of the forming die; The large-curvature and wide-width slab and the forming mold are integrally packaged and vacuumized; Keeping the vacuum state, placing the large curvature and wide width slab and the forming mold into the autoclave; The autoclave is heated, and when the large curvature and wide width slab reaches a first preset temperature, the temperature is kept for a first preset time, and the large curvature and wide width slab is kept in a vacuum state; when the first preset temperature is reached, a first pressure is applied to the surface of the part; When the first preset time is reached, the temperature is continuously raised to the second preset temperature and then kept warm for the second preset time, and a second pressure is applied to the surface of the part so that the outer surface of the large curvature and wide width slab is completely fitted with the inner surface of the forming mold; When the second preset time is reached, the temperature starts to drop, and when the mold temperature drops to the third preset temperature, the pressure is unloaded to obtain the ribbed integral wall panel.

5. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 4, characterized in that: The curvature radius R of the forming die m1 =1.2R 挤压 ~1.5R 挤压 , where R 挤压 is the radius of the extrusion die during extrusion.

6. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 4, characterized in that: The forming die profile is a die profile calculated by a creep aging forming method to compensate for the springback amount.

7. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 4, characterized in that: The first pressure P1 is 0.2P-0.5P, wherein P is the pressure required for the outer surface of the large curvature and wide width slab to fully fit with the molding surface of the forming mold calculated by the finite element method.

8. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 7, characterized in that: The second pressure P2 is P.

9. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 1, characterized in that: Before the cylindrical ribbed wall panel blank is manufactured by extrusion, the method also includes: The aluminum alloy billet and the extrusion die are heated to the aluminum alloy solution heat treatment temperature and kept at this temperature for a preset time.

10. The method for coordinating the shape and properties of the ribbed integral wall panel according to claim 9, characterized in that: The method of manufacturing the cylindrical ribbed wall panel blank by extrusion is specifically as follows: During extrusion, the temperature of the extrusion die and the extrusion barrel is greater than the solution heat treatment temperature of the aluminum alloy, and the extrusion speed of the extrusion barrel is 0.2-0.5 mm / s.

Images