Co-curing forming method for winglet of double-curvature laminated board structure

Abstract

The invention discloses a co-curing forming method for a winglet of a double-curvature laminated board structure. The co-curing forming method comprises the following steps: firstly, designing a silicone rubber soft mold matched with the inner molded surface of a product, dividing the silicone rubber soft mold into three parts, and respectively paving prepreg; after a copper net is laid on a lower die of the product metal forming die, a lower skin laying layer continues to be laid according to the laying layer design sequence; a silicone rubber soft mold is placed on the lower skin laying layer, and then an upper skin laying layer is laid on the silicone rubber soft mold; paving a copper mesh on an upper mold of a product metal forming mold, placing the product metal forming mold on the upper skin paving layer, and closing the mold; and finally, curing, molding and demolding to obtain a product. The forming method is simple in process and easy to operate, a conventional autoclave process is optimized into a low-cost curing oven forming process, and the manufacturing cost is greatly reduced; and the prepared silicone rubber soft mold can be repeatedly used, and meanwhile, the use of bonding glue and rivets is eliminated, so that a large amount of labor cost and mold cost are saved.

Description

Technical Field

[0001] The present invention relates to the technical field of composite material manufacturing, and particularly relates to a co-curing forming method for a winglet with a double-curvature laminate structure. Background Art

[0002] As an additional structure at the end of the wing of a civil aircraft, the winglet is firmly connected to the wing through its root center joint. With excellent aerodynamic performance, this design can significantly interfere with the air flow in the wing tip area, thereby effectively reducing the induced drag during the high-speed flight of the aircraft. For most transport aircraft models, the induced drag accounts for about 40% of the total drag during flight. Therefore, the application of winglets not only helps to save fuel consumption, but also shows significant economic benefits in reducing the operating costs of aircraft.

[0003] In recent years, under the background of the aviation industry's pursuit of higher performance and more efficient energy, the demand for lightweight, high-strength, and low-cost structures has become increasingly urgent. Under this premise, more and more winglets have begun to adopt a laminate structure, in which the skin, beams, and ribs cooperate with each other to effectively enhance the overall stiffness and improve the stability and anti-deformation ability of the winglet.

[0004] The common forming method for the laminated winglet is autoclave molding, including two methods: secondary bonding and co-bonding. Secondary bonding means using an adhesive to bond two or more cured composite parts together. During the bonding process, the adhesive undergoes a chemical reaction and cures, thus achieving the connection of the parts. The advantages are that it can connect parts of different shapes and sizes, with relatively high connection strength and reliability. The disadvantages are that the process is relatively complex, and precise machining and positioning of the parts are required to ensure the bonding quality. Co-bonding means bonding and curing one or more cured parts together with one or more uncured prepregs. During the curing process, the resin in the prepregs undergoes a chemical reaction to form a firm connection with the cured parts. The advantages are that it can achieve one-step forming, reduce the process and assembly time, and improve production efficiency. The disadvantages are that it has high requirements for process control, and parameters such as curing temperature, pressure, and time need to be precisely controlled to ensure the bonding quality and structural performance. In addition, during the secondary bonding and co-bonding processes, although the use of rivets simplifies the assembly process, the weight of the rivets themselves and their impact on the structural strength cannot be ignored. Therefore, although the laminated structure has significant advantages in weight reduction and stiffness improvement, there are still many challenges in its forming process, including: (1) The autoclave process is expensive to manufacture; (2) The complex assembly and positioning process leads to relatively low production efficiency; (3) Although the use of adhesives can provide good connection effects, factors such as their weight and curing time limit their application in lightweight design; (4) Although the use of rivets simplifies the assembly process, the weight of the rivets themselves and their impact on the structural strength cannot be ignored; (5) There are many molds and high-precision assembly requirements, and the mold manufacturing cost is high. Summary of the Invention

[0005] In view of the problems existing in the above background technology, the present invention designs a co-curing forming method for a double-curvature laminated winglet structure. This method is only applicable to the laminated winglet without ribs. Through the design of non-autoclave co-curing manufacturing technology and the combination of large-size, high-precision, double-curvature combined die tooling design, a co-curing forming method with low cost, lightweight manufacturing technology, simplified manufacturing process, and controllable quality is provided.

[0006] To achieve the above invention purpose, the present invention provides the following technical solutions:

[0007] A co-curing forming method for a double-curvature laminated winglet structure, comprising the following steps:

[0008] (1) Silicone rubber soft mold design and laying design: Design a silicone rubber soft mold adapted to the inner surface of the product according to the product structure. Then, according to the requirements of the product forming cavity, it is divided into three parts, and prepregs are laid on each part respectively;

[0009] On the lower two parts of the silicone rubber soft mold, a glass fiber prepreg is used as the first layer, and several layers (≥1 layer) of carbon fiber prepregs are laid in the order of the ply design.

[0010] On the top of the silicone rubber soft mold, first lay a layer of glass fiber prepreg, which has an assembly relationship with the metal connecting rib (i.e., the connecting piece between the wing and the fuselage). Then, continue to lay several layers (≥1 layer) of carbon fiber prepregs in the order of the ply design.

[0011] The ply design order is to repeat the laying at the laying angles of ±45 and 0 / 90.

[0012] (2) Lower die paving design of the product metal forming mold: After laying a layer of copper mesh on the lower die of the product metal forming mold, continue to lay several layers of carbon fiber prepregs above it in the order of the ply design to complete the paving of the remaining lower skin ply.

[0013] The ply design order is to repeat the laying at the laying angles of ±45 and 0 / 90.

[0014] (3) Assembly of the silicone rubber soft mold and the product metal forming mold: Place the structure in step (1) with the lower part of the silicone rubber soft mold as the bottom on the ply laid in step (2), and use the large end cover plate and silicone rubber positioning screw tooling in the product metal forming mold to position and assemble the silicone rubber soft mold. Then, continue to lay the remaining upper skin ply above the silicone rubber soft mold according to the ply design.

[0015] The laying order of the upper skin ply is to repeat the laying of several layers of carbon fiber prepregs at the laying angles of 0 / 90 and ±45, and it is a symmetric design with the carbon fiber prepreg layer laid above the silicone rubber soft mold.

[0016] When the silicone rubber soft mold is placed in the middle of the product metal forming mold, its left and right ends are respectively in contact with the large end cover plate and the small end cover plate of the product metal forming mold.

[0017] (4) Upper die paving design and mold closing of the product metal forming mold: After laying a layer of copper mesh on the upper die of the product metal forming mold, place this structure on the upper skin ply in step (3) and perform mold closing.

[0018] (5) Curing and forming: Place the forming mold and the product obtained in step (4) together in a curing furnace for curing and forming; during the heating-up process of the curing furnace, the silicone rubber expands due to heat and presses the product.

[0019] The curing temperature is 120 - 180 °C, and the curing time is 1 - 3 h.

[0020] (6) Demolding: After the curing and forming is completed, first remove the front baffle of the product metal forming mold, and then directly pull out the silicone rubber soft mold. Since the silicone rubber has a certain elasticity, removing the upper metal mold can obtain the double-curvature laminate structure winglet described in the present invention; this demolding process is simple and easy to operate, saving a large amount of labor costs;

[0021] Both the silicone rubber soft mold and the product metal forming mold match the shape and structure of the product, and the outer shape of the product metal forming mold is double-curved.

[0022] Furthermore, in steps (2) and (3) of the present invention, a staggered layer design needs to be considered for the leading edge to avoid weak connections at the same location of the product. The spacing between the splicing seams is generally ≥ 25 mm. There are two splicing methods, namely lapping and butting, which can be determined according to actual requirements; the lapping width is generally 12.5 - 25.4 mm, and the splicing gap ≤ 1.5 mm.

[0023] Furthermore, the carbon fiber prepreg of the present invention has a fiber areal weight of 100 - 400 g / m 2 , and the resin content is 30% - 50%; the glass fiber prepreg has a fiber areal weight of 50 - 100 g / m 2 , and the resin content is 40% - 80%.

[0024] Furthermore, the outermost layer of the winglet of the present invention is a lightning protection surface film with a areal weight of 100 - 400 g / m 2 ; the inner layer of the assembly surface of the winglet that is connected to the metal connecting rib (i.e., the connecting part between the winglet and the wing) is a glass fiber prepreg with a relatively small areal weight.

[0025] Furthermore, the laying layers of the carbon fiber prepreg in each part and the prepreg parameters are designed according to the load-bearing, thickness, and weight requirements of the winglet. The amount of each layer of prepreg is determined according to the product area. The increase of the ±45° ply can improve the shear resistance of the product.

[0026] The winglet of the present invention adopts a co-curing forming process. Three different types of molds are required in this process, namely a silicone rubber forming metal mold, a silicone rubber soft mold, and a product forming metal mold. During the curing process, after the silicone rubber mold expands due to heat, it can provide the necessary forming pressure for the product, while the product forming metal mold is responsible for ensuring the size and accuracy of the outer surface of the product.

[0027] Furthermore, the silicone rubber soft mold of the present invention is obtained by curing at room temperature using a silicone rubber forming metal mold. The structure of the silicone rubber forming metal mold includes a left mold, a right mold, two partition plates, a large end plate, a small end plate, and a support frame. Among them, the upper and lower parts of the left mold and the right mold are respectively installed and connected through the large end plate and the small end plate. The two partition plates are perpendicular to the large and small end plates and are placed between the two end plates. The left mold and the right mold are placed on the support frame. Sealing grooves are provided on the left mold, the right mold, the large end plate, and the small end plate. The partition plates are positioned with the left and right molds through positioning grooves.

[0028] Since the silicone rubber male mold is cured at room temperature, the material of the silicone rubber forming metal mold is aluminum alloy. Sealing grooves are designed on the left and right molds, the large end plate, and the small end plate to prevent the silicone rubber from flowing out of the mold before curing. The partition plates are positioned with the left and right molds through positioning grooves.

[0029] Furthermore, the structure of the product forming metal mold of the present invention includes an upper mold, a lower mold, a large end cover plate, a small end cover plate, inserts, silicone rubber positioning screws, mold clamping blocks, and guide columns. Among them, the left and right sides of the upper mold and the lower mold are respectively installed and connected through the large end cover plate and the small end cover plate. The upper mold and the lower mold are positioned and clamped through the mold clamping blocks and the guide columns. The inserts are placed between the upper and lower molds. The silicone rubber positioning screws are located on the large end cover plate. The silicone rubber positioning screws are M24 hexagon socket head cap screws.

[0030] The upper and lower half molds are used to ensure the overall external dimensions of the winglet. When the upper and lower half molds are clamped, they are mainly positioned through the mold clamping blocks and the guide columns, and are locked with M24 hexagon socket head cap screws. The winglet is relatively large in size and has a double-curved shape. To reduce the weight of the mold and ensure the strength of the mold, reinforcing ribs are designed on the back of the mold.

[0031] In the present invention, since the forming temperature of the winglet is 120 - 180 °C, in order to improve the forming accuracy of the product, the expansion deformation of the mold under high temperature conditions needs to be considered. Therefore, the mold cavity should be designed to be slightly smaller during design. The expansion size is calculated according to formula (1):

[0032]

[0033] In the formula: ΔL is the expansion size, L is the product size, and ε is the linear expansion coefficient of the metal.

[0034] Compared with the prior art, the present invention has the following beneficial effects:

[0035] (1) The forming method of the present invention optimizes the conventional autoclave process into a low-cost curing furnace forming process, greatly reducing the manufacturing cost.

[0036] (2) The forming method of the present invention has simple and easy-to-operate production processes. At the same time, the silicone rubber soft mold can be reused multiple times, saving a large amount of labor costs and mold costs.

[0037] (3) The molding method of the present invention eliminates the use of adhesive and rivets, providing a prerequisite for lightweight design.

[0038] (4) In the molding method of the present invention, the design of the soft-hard combined mold provides effective molding pressure and surface guarantee for the co-curing design of the laminated winglet. The measured porosity of the part meets the requirement of ≤2%; the profile deviation meets the requirement of ±0.75 mm; the area of a single internal defect meets the requirement of ≤100 mm 2 requirement. Description of the Drawings

[0039] Figure 1 is a schematic structural view of the winglet described in the present invention.

[0040] Figure 2 is a schematic structural view and A-A sectional view of the silicone rubber molding die described in the present invention.

[0041] Figure 3 is a schematic structural view of the formed silicone rubber soft die described in the present invention.

[0042] Figure 4 is a front view of the structural view of the product molding metal die described in the present invention.

[0043] Figure 5 is a right view of the structural view of the product molding metal die described in the present invention.

[0044] Figure 6 is a schematic structural view of the combined module and guide post in the product molding metal die described in the present invention.

[0045] Figures 1 to 6 Each label is: 1 large end plate, 2 left die, 3 support frame, 4 small end plate, 5 right die, 6 partition plate,

[0046] 7 positioning groove, 8 large end cover plate, 9 small end cover plate, 10 upper die, 11 silicone rubber positioning screw, 12 lower die,

[0047] 13 insert, 14 combined module, 15 guide post. Detailed Embodiments

[0048] For better understanding and implementation, the present invention will be described in detail below with reference to the drawings.

[0049] The winglet described in the present invention adopts a co-curing molding process, and three different types of molds are required in this process, namely, a silicone rubber molding metal die, a silicone rubber soft die, and a product molding metal die. During the curing process, after the silicone rubber die expands due to heat, it can provide the necessary molding pressure for the product, while the product molding metal die is responsible for ensuring the size and precision of the external profile of the product.

[0050] The silicone rubber soft mold is obtained by curing at room temperature using a metal mold formed by silicone rubber. The structure of the metal mold formed by silicone rubber includes a left mold 2, a right mold 5, two partition plates 6, a large end plate 1, a small end plate 4, and a support frame 3. Among them, the upper and lower parts of the left mold 2 and the right mold 5 are respectively installed and connected through the large end plate 1 and the small end plate 4. The two partition plates are parallel to the large and small end plates and are placed between the two end plates. The left mold and the right mold are placed on the support frame. Sealing grooves are provided on the left mold, the right mold, the large end plate, and the small end plate. The partition plates are positioned with the left and right molds through positioning grooves 7.

[0051] Since the silicone rubber male mold is cured at room temperature, the material of the metal mold formed by silicone rubber is aluminum alloy. Sealing grooves are designed on the left and right molds, the large end plate, and the small end plate to prevent the silicone rubber from flowing out of the mold before curing. The partition plates are positioned with the left and right molds through positioning grooves.

[0052] The structure of the metal mold for product forming includes an upper mold 10, a lower mold 12, a large end cover plate 8, a small end cover plate 8, an insert 13, a silicone rubber positioning screw 11, a mold clamping block 14, and a guide post 15. Among them, the left and right sides of the upper mold and the lower mold are respectively installed and connected through the large end cover plate and the small end cover plate. The upper mold and the lower mold are positioned and clamped through the mold clamping block and the guide post. The insert is placed between the upper and lower molds. The silicone rubber positioning screw is located on the large end cover plate. The silicone rubber positioning screw is an M24 hexagon socket head cap screw.

[0053] The upper and lower half molds are used to ensure the overall external dimensions of the winglet. When the upper and lower half molds are clamped, they are mainly positioned through the mold clamping block and the guide post, and locked with M24 hexagon socket head cap screws. The winglet has a large size and a double-curved shape. To reduce the weight of the mold and ensure the strength of the mold, reinforcing ribs are designed on the back of the mold.

[0054] A co-curing forming method for a double-curved laminated structure winglet includes the following steps:

[0055] (1) Silicone rubber soft mold design and laying design: Design a silicone rubber soft mold adapted to the inner surface of the product according to the product structure. Then, according to the requirements of the product forming cavity, it is divided into three parts, and prepreg is laid on each part respectively.

[0056] On the lower two parts of the silicone rubber soft mold, 14# is used as the first layer, and it is laid in the laying design order of 13# to 8#.

[0057] On the top of the silicone rubber soft mold, a layer of 14# is first laid. This layer has an assembly relationship with the metal connecting rib (i.e., the connecting piece between the wing and the winglet). Then, it is laid in the laying design order of 13# to 8#.

[0058] The silicone rubber mold is designed with reference to the HB Z 245-1993 specification. The forming pressure is ≥0.4 MPa, meeting the usage requirements. The theoretically calculated results of the volume and stress of each mold cavity are shown in Table 1;

[0059] Table 1 The theoretically calculated results of the stress of each mold cavity

[0060]

[0061] (2) Lower die paving design of the product metal forming mold: After paving a layer of No. 1 on the lower die of the product metal forming mold, continue to pave No. 2 - No. 7 above it in the paving design order to complete the paving of the remaining lower skin layer;

[0062] (3) Assembly of the silicone rubber soft mold and the product metal forming mold: Place the structure in step (1) with the lower part of the silicone rubber soft mold as the bottom on the paving layer in step (2), and use the large end cover plate and the silicone rubber positioning screw tooling in the product metal forming mold to position and assemble the silicone rubber soft mold. Then, continue to pave the remaining upper skin layers No. 7 - No. 2 above the silicone rubber soft mold according to the paving design;

[0063] When the silicone rubber soft mold is placed in the middle of the product metal forming mold, its two ends are respectively in contact with the large end cover plate and the small end cover plate of the product metal forming mold;

[0064] (4) Upper die paving design and mold closing of the product metal forming mold: After paving a layer of No. 1 on the upper die of the product metal forming mold, place this structure on the upper skin layer in step (3) and close the mold;

[0065] (5) Curing and forming: Place the forming mold and the product obtained in step (4) together in a curing furnace for curing and forming; during the heating-up process of the curing furnace, the silicone rubber expands due to heat and pressurizes the product;

[0066] The curing temperature is 120 - 180 °C, and the curing time is 1 - 3 h;

[0067] (6) Demolding: After the curing and forming is completed, first remove the front baffle of the product metal forming mold, and then directly pull out the silicone rubber soft mold. Since the silicone rubber has a certain elasticity, removing the metal upper die can obtain the double-curvature laminated structure winglet described in the present invention; this demolding process is simple and easy to operate, saving a large amount of labor costs;

[0068] The silicone rubber soft mold and the product metal forming mold both match the shape and structure of the product, and the outer shape of the product metal forming mold is double-curved;

[0069] For the structural ply design of the present invention, specific prepreg parameters and ply numbers are selected according to the load-bearing capacity, thickness, and weight requirements of the winglet. The ply generally adopts a symmetric ply. The increase of the ±45° ply can improve the shear resistance of the product. A typical overall structure paving design is shown in Table 1.

[0070] Table 2 Typical overall ply design

[0071]

[0072]

[0073] In steps (2) and (3) of the present invention, a staggered ply design needs to be considered for the leading edge to avoid weak connections at the same location of the product. The splicing seam spacing is generally ≥25 mm. There are two splicing methods: lap joint and butt joint, which can be determined according to actual requirements; the lap joint width is generally 12.5 - 25.4 mm, and the splicing gap ≤1.5 mm.

[0074] For the carbon fiber prepreg of the present invention, the fiber areal weight is 100 - 400 g / m 2 , and the resin content is 30% - 50%; for the glass fiber prepreg, the fiber areal weight is 50 - 100 g / m 2 , and the resin content is 40% - 80%.

[0075] The outermost layer of the winglet of the present invention is a lightning protection surface film with an areal weight of 100 - 400 g / m 2 ; the inner layer of the assembly surface of the winglet that is connected to the metal connecting rib (i.e., the connecting part between the winglet and the wing) is a glass fiber prepreg with a smaller areal weight.

[0076] The laying number of the carbon fiber prepreg in each part and the prepreg parameters are designed according to the load-bearing capacity, thickness, and weight requirements of the winglet. The amount of prepreg used per layer is determined according to the product area. The increase of the ±45° ply can improve the shear resistance of the product.

[0077] In the present invention, since the forming temperature of the winglet is 120 - 180 °C, in order to improve the forming accuracy of the product, the expansion deformation of the mold under high temperature conditions needs to be considered. Therefore, the mold cavity should be designed to be slightly smaller during design, and the expansion size is calculated according to formula (1):

[0078]

[0079] In the formula: ΔL is the expansion size, L is the product size, and ε is the linear expansion coefficient of the metal.

[0080] The co-curing forming method of the present invention is only applicable to the laminate winglet without ribs. Through the design of non-autoclave co-curing manufacturing technology and the combination of large-size, high-precision, double-curvature combined die tooling design, a co-curing forming method with low cost, lightweight manufacturing technology, simplified manufacturing process and controllable quality is provided.

Claims

1. A co-curing molding method for a winglet with a double curvature laminate structure, characterized in that: The steps include: (1) Silicone rubber soft mold design and paving design: According to the product structure, a silicone rubber soft mold suitable for the inner surface of the product is designed. Then, according to the requirements of the product molding cavity, it is divided into three parts, and prepreg is laid in each part; The two lower parts of the silicone rubber soft mold are both provided with glass fiber prepreg as the first layer, and a plurality of layers or more of carbon fiber prepreg are laid according to the ply design sequence; A layer of glass fiber prepreg is first laid on the top of the silicone rubber soft mold, and the layer is in an assembly relationship with the metal connecting rib, and then several layers of carbon fiber prepreg are laid according to the layer laying design sequence. ≥1 layer; (2) Design of the lower mold pavement of the product metal forming mold: After a layer of copper mesh is laid on the lower mold of the product metal forming mold, several layers of carbon fiber prepreg are laid on it according to the ply design sequence to complete the plying of the remaining lower skin ply; The metal forming molds of the products are matched with the shape and structure of the products, and their appearance is a double curvature; they mainly include an upper mold, a lower mold, a large end cover plate and a small end cover plate, and the upper mold and the lower mold are respectively installed and connected by the large end cover plate and the small end cover plate on the left and right; The ply design sequence in step (1) and step (2) is repeated at a ply angle of ±45 and 0 / 90; (3) Assembling the silicone rubber soft mold and the product metal forming mold: placing the structure of step (1) on the layer in step (2) with the lower part of the silicone rubber soft mold as the bottom, and then continue to lay the remaining upper skin layer on top of the silicone rubber soft mold according to the layer design; When the silicone rubber soft mold is placed in the middle of the product metal forming mold, its left and right ends are respectively fitted with the large end cover plate and the small end cover plate of the product metal forming mold; The upper skin layer laying sequence is to repeatedly lay several layers of carbon fiber prepreg at laying angles of 0 / 90 and ±45, and the carbon fiber prepreg layer laid on the silicone rubber soft mold is symmetrically designed; (4) Design of upper mold paving and mold closing of product metal forming mold: After a layer of copper mesh is laid on the upper mold of the product metal forming mold, the structure is placed on the upper skin layer of step (3) and mold closing is performed; (5) Curing and molding: placing the molding mold and the product obtained in step (4) in a curing furnace for curing and molding; (6) Demolding: After the curing molding is completed, the front baffle of the product metal molding mold is first disassembled, and then the silicone rubber soft mold is directly pulled out, and the metal upper mold is removed to obtain the double-curvature laminate structure winglet.

2. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 1, characterized in that: The carbon fiber prepreg has a fiber surface weight of 100 to 400 g / m 2 , wherein the resin content is 30% to 50%; the glass fiber prepreg has a fiber surface weight of 50-100g / m 2 , wherein the resin content is 40% to 80%; the outermost layer of the winglet is a lightning protection surface film with a surface weight of 100 to 400 g / m 2 .

3. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 2, characterized in that: The curing temperature in step (5) is 120-180° C., and the curing time is 1-3 hours.

4. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 3, characterized in that: When the structure of step (1) in step (3) is placed on the ply in step (2), a staggered design is adopted, and the splicing method is overlap or butt joint, the overlap width is 12.5-25.4mm, and the splicing gap is ≤1.5mm.

5. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 3, characterized in that: The number of layers of the carbon fiber prepreg laid at each location and the prepreg parameters are designed according to the load, thickness and weight requirements of the winglet, and the amount of prepreg per layer is determined according to the product area.

6. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 3, characterized in that: The silicone rubber soft mold is obtained by curing at room temperature using a silicone rubber molding metal mold; The silicone rubber molding metal mold structure comprises a left mold (2), a right mold (5), two partition plates (6), a large end plate (1), a small end plate (4) and a support frame (3), wherein the left mold (2) and the right mold (5) are respectively connected by the large end plate (1) and the small end plate (4) at the top and bottom, and the two partition plates (6) are perpendicular to the large and small end plates and are placed between the two end plates; The left mold (2) and the right mold (5) are placed on the support frame (3); the left mold, the right mold, the large end plate and the small end plate are all provided with sealing grooves; the partition plate is positioned with the left and right molds through positioning grooves (7); The material of the silicone rubber molding metal mold is aluminum alloy.

7. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 3, characterized in that: The product forming metal mold structure specifically comprises an upper mold (10), a lower mold (12), a large end cover plate (8), a small end cover plate (9), an insert (13), a silicone rubber positioning screw (11), a closing mold block (14) and a guide column (15); The upper mold and the lower mold are installed and connected on the left and right sides through the large end cover plate and the small end cover plate respectively. The upper mold and the lower mold are positioned and clamped through the clamping module and the guide column. The insert is placed between the upper and lower molds, and the silicone rubber positioning screw is located on the large end cover plate.

8. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 7, characterized in that: When the silicone rubber soft mold is placed in the product metal forming mold, it is positioned and assembled through the large end cover plate and the silicone rubber positioning screw tooling.

9. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 7, characterized in that: The back side of the product forming metal mold is also provided with reinforcing ribs.

10. The co-curing molding method of a winglet with a double curvature laminate structure according to claim 3, characterized in that: The product molding metal mold cavity is smaller than the product size.

Images