A ceramic wood-replacement forming carbon fiber grid rib skin shell segment composite mold

Abstract

The application discloses a ceramic wood replacement forming carbon fiber grid rib skin shell segment composite mold, which comprises a male mold, the male mold comprises a base, a male mold body and two ceramic wood replacement units, the male mold body is fixed to the outer circumferential side of the base, the male mold body is combined by a plurality of male mold blocks, and the outer circumferential side of the male mold body comprises two opposite edge sides; the two ceramic wood replacement units are respectively fixed to the two edge sides. The principle of the mold is that external pressure is applied through a floating steel outer male mold, the uniformity of the pressure is ensured through mold floating, the shape profile of the product is ensured, the principle of high continuity ratio of longitudinal and transverse grid ribs of the internal grid ribs is ensured through the combination of the steel blocks and the two-side edge ceramic wood replacement molds, and the demolding of the two-side edge molds is facilitated, and the technical problems that the forming quality of the cabin segment is not easy to guarantee in the machining of the prior art and the demolding is not easy after the machining and forming are solved.

Description

Technical Field

[0001] This application belongs to the field of aerospace composite material molding technology, specifically relating to a molding die for a carbon fiber composite irregular mesh structure compartment. Background Technology

[0002] Carbon fiber composites possess advantages such as light weight, high strength, high stiffness, high specific strength, and high specific stiffness, leading to their widespread application in aerospace, automotive, and marine industries. Currently, some aerospace components require specialized molds for molding. However, existing mold-making methods suffer from challenges in ensuring molding quality and difficulty in demolding after molding. Utility Model Content

[0003] This application aims to at least partially address one of the technical problems in the related art.

[0004] To address the aforementioned technical issues, this application provides a composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segments. This mold improves the processing quality of the segments, ensures processing quality, and facilitates demolding after the segments are formed.

[0005] The technical solution adopted to achieve the purpose of this application is as follows:

[0006] The ceramic-wood-substitute carbon fiber mesh reinforced shell segment composite mold of this application includes a male mold, which includes:

[0007] Base;

[0008] The male mold body is fixed to the outer periphery of the base. The male mold body is assembled from multiple male mold blocks. The outer periphery of the male mold body is provided with multiple first rib grooves arranged in a cross pattern for the mesh ribs of the compartment to be embedded. The outer periphery of the male mold body includes two oppositely arranged edge sides.

[0009] Two ceramic wood substitute units are fixed to the two edge sides respectively, and the two ceramic wood substitute units are used to break after the compartment is formed to achieve demolding of the male mold.

[0010] In some technical solutions, the base is a tubular structure, and the base is provided with multiple fixing points, which are used to fix multiple male mold blocks respectively.

[0011] In some technical solutions, the cross-section of the base is triangular, and the two side edges are respectively arranged opposite to the two side edges of the triangle in the inward and outward directions;

[0012] And / or, the male mold assembly block is a steel block, and the ceramic wood substitute unit is a ceramic wood substitute.

[0013] In some technical solutions, the multiple male mold blocks are divided into multiple block rings and multiple block rows. Each block ring includes multiple male mold blocks arranged sequentially along the circumference of the base, and each block row includes multiple male mold blocks arranged sequentially along the axial direction of the base.

[0014] In some technical solutions, the first rib groove is restricted between two adjacent block rings and between two adjacent block rows.

[0015] In some technical solutions, the ceramic wood-substitute unit includes multiple ceramic wood-substitute blocks, which are arranged sequentially and connected along the axial direction of the base.

[0016] In some technical solutions, the ceramic wood substitute unit is provided with a plurality of second rib grooves for the mesh ribs to be embedded. The plurality of second rib grooves are arranged at intervals along the axial direction. The plurality of second rib grooves correspond to and communicate with the first rib grooves that extend circumferentially along the base among the plurality of first rib grooves, and at least a portion of the second rib grooves are formed between two ceramic wood substitute blocks.

[0017] In some technical solutions, the composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment also includes:

[0018] A first reinforcing frame is disposed at one end of the axial direction of the base, and one end of the base and one end of the male mold body are both connected to the first reinforcing frame;

[0019] The second reinforcing frame is located at the other end of the axial direction of the base, and the other end of the base and the other end of the male mold body are both connected to the second reinforcing frame.

[0020] In some technical solutions, a female mold is also included. The female mold has a hollow structure and is sleeved on the outer periphery of the male mold. A cavity for processing the compartment is defined between the male mold and the female mold. The female mold is connected between the first reinforcing frame and the second reinforcing frame.

[0021] In some technical solutions, the female mold includes multiple female mold segments, which are sequentially connected along the circumference of the male mold, and the female mold segments are movable in the inward and outward directions so that the female mold can float and change during the processing of the compartment.

[0022] As can be seen from the above technical solution, the composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment of this application improves the processing quality of the segment, ensures the processing quality, and facilitates demolding after the segment is formed. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a three-dimensional structural schematic diagram of the male mold in the embodiments of this application.

[0025] Figure 2 This is a schematic diagram of the base structure in an embodiment of this application.

[0026] Figure 3 This is a schematic diagram of the male mold body in the embodiments of this application.

[0027] Figure 4 This is a schematic diagram of the assembly of the male mold body and the ceramic wood substitute unit in the embodiments of this application.

[0028] Figure 5 This is a schematic diagram showing the arrangement of the block ring and block row formed by multiple male mold blocks in the embodiments of this application.

[0029] Figure 6 This is a schematic diagram of the ceramic wood substitute unit in the embodiments of this application.

[0030] Figure 7 This is a schematic diagram of the assembly of the positive mold body and the ceramic wood substitute unit in the embodiments of this application.

[0031] Figure 8 This is a schematic diagram of the structure of the first and second reinforcing frames in the embodiments of this application.

[0032] Figure 9 This is a schematic diagram of the female mold being assembled on the outer periphery of the male mold in an embodiment of this application.

[0033] Figure 10 This is an exploded view of the female mold in the embodiments of this application.

[0034] Figure 11 This is a schematic diagram of the rotary bracket in the embodiments of this application.

[0035] Figure 12 This is a schematic diagram of the ceramic-wood-substitute carbon fiber mesh reinforcement shell segment composite mold assembled onto the rotary bracket in an embodiment of this application.

[0036] Figure 13 This is a schematic diagram of the processed and prepared compartment in the embodiments of this application.

[0037] Explanation of reference numerals in the attached figures:

[0038] 1-Base; 11-Fixed point;

[0039] 2-Main body of the male mold; 21-Main mold assembly block; 22-First rib groove; 23-Edge side; 24-Assembly block ring; 25-Arsembly block row;

[0040] 3-Ceramic-wood substitute unit; 31-Ceramic-wood substitute interlocking block; 32-Second rib groove;

[0041] 4-First reinforcing frame; 5-Second reinforcing frame;

[0042] 100 - Male mold; 200 - Female mold; 201 - Female mold flap; 300 - Rotary bracket; 400 - Cabin section. Detailed Implementation

[0043] To enable those skilled in the art to more clearly understand this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0044] It should be noted that this application is based on the inventor's discovery and understanding of the following facts and problems:

[0045] Currently, composite material cabins with mesh reinforcement and skin structures are widely used in key fields such as aerospace due to their significant lightweight advantages compared to aluminum alloy and titanium alloy cabins. The composite mesh structure is a mesh-like rib structure, where the ribs are made of unidirectional prepreg fibers wound together. Based on the shape of the mesh, it can be classified into orthogonal mesh structures, triangular mesh structures, and hexagonal mesh structures. Its outstanding features include high specific strength / specific modulus, low production cost, high structural efficiency, and excellent stability. Composite mesh structures are used in various cabin sections, including launch vehicle fairings, interstage sections, strategic missile nose cones, and transition sections.

[0046] The convex-concave curved surface integrated irregularly shaped compartment carbon fiber composite shell is composed of a series of axial and circumferential mesh reinforcements. The axial mesh reinforcements and skin layers with different angles of layup and flanges form the end frame. After the shell is formed, an external heat insulation layer is required to form an integrated load-bearing and heat-insulating structure. Because the mesh reinforcements and skin form an integrated end frame structure, using fabric to achieve this is costly, has low material utilization, and the mesh reinforcements are practically impossible to implement. Furthermore, using fabric for the outer skin has relatively poor overall performance compared to unidirectional tape, in terms of designability and processability. Therefore, the shell is prepared using bismaleimide resin-based carbon fiber prepreg unidirectional tape or fabric layup. The following five technical challenges are encountered during the compartment fabrication process:

[0047] First, there is the issue of demolding irregularly shaped rotating mesh rib cabins. Due to the large number of longitudinal and transverse mesh ribs on the internal shape of the irregularly shaped cabin with convex and concave curved surfaces, and the sharp angles formed on both sides of the windward and leeward transition zone, which includes circumferential and longitudinal mesh ribs and support frames, it is basically impossible to demold using traditional metal structures. Even if demolding is possible, it needs to be subdivided into many pieces, and the positioning and connection between the pieces cannot be achieved by traditional screwing and gluing. Using a gluing solution, however, causes the problem of not being able to demold.

[0048] Secondly, the cabin structure requires that the continuous ratio of longitudinal and transverse fibers at the cross-section of the mesh reinforcement exceeds 75% in one direction. The mold at the cross-section needs to be prepared with a certain radius to allow the fibers to be pre-cured in an equal volumetric manner during later laying. Because the soft mold made of silicone rubber is insufficient in hardness and compressive strength, it is impossible to achieve the goal of periodically hammering and dispersing the mesh reinforcement at the cross-section. When water-soluble resin sand or gypsum material is used to make the mold, its own strength and hardness are insufficient and it cannot withstand the high-temperature performance requirements of the 240℃ curing temperature of bismaleimide resin.

[0049] Thirdly, since the end frame of the cabin section is an important structure for load-bearing and force transmission, the end frame of the carbon fiber cabin is formed by combining the axial mesh reinforcement flange, skin, and 0° / ±45° unidirectional band flange in the end frame transition reinforcement area. This ensures that the cabin sections can effectively transmit force and connect through the end frame, while ensuring that the assembly structure of the corner fittings inside the end frame avoids interference problems. Therefore, the mold end frame part needs to provide a certain strength and hardness to ensure smooth fiber laying process and to ensure that the end frame does not produce large deformation during curing. The L-corner inside the end frame must meet the assembly requirements of the corner fitting surface clearance, avoiding the formation of excessive R-corner radius at the inner corner and the inward or outward turning of the end frame itself, which would not be able to guarantee the subsequent installation of corner fittings and excessive assembly stress.

[0050] Fourthly, the performance and contour of the negative curvature areas on both sides of the cabin's back panel need to be precisely guaranteed. This ensures that excessive mold linear expansion during curing does not cause bridging, delamination, or debonding defects in the mesh reinforcement and skin. Simultaneously, the overall contour accuracy of the cabin after curing must be controlled to ensure successful assembly of the subsequent external heat insulation layer. Since the assembly gap is 0.8-1mm, the contour accuracy must be precisely controlled within 0.5-0.6mm to ensure successful assembly while avoiding problems such as excessive assembly stress due to too small an assembly gap, or insufficient interfacial bonding strength due to too small an shape and too large an assembly gap. Therefore, aluminum alloys and silicone rubber with high coefficients of thermal expansion should not be used for the mold material. Furthermore, expensive mold materials such as titanium alloys and Invar steel should be avoided; P20-like mold steel is more suitable. In addition, the design of the female mold is also crucial. It must ensure that the fibers at the intersections of the mesh reinforcement can achieve final fiber dispersion and compression under external force during curing, while simultaneously ensuring the contour accuracy requirements of the overall shape during curing.

[0051] Based on the above facts and problems, this application provides a composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement skin shell segment.

[0052] The following describes an embodiment of the composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment of this application.

[0053] like Figure 1 As shown, the composite mold for ceramic wood substitute molding carbon fiber mesh reinforcement shell segment of this application includes a male mold, which includes a base 1, a male mold body 2 and two ceramic wood substitute units 3.

[0054] For example, such as Figure 2 As shown, the base 1 can be a tubular structure with a hollow interior. The axial direction of the base 1 can be front-to-back. The base 1 can be made of steel. The base 1 can be a stepped structure, meaning that the base 1 can include a small section with a smaller radial dimension and a large section with a larger radial dimension. The radial dimension of the large section is larger than that of the small section. Thus, the base 1 presents a structure with a larger dimension at one end and a smaller dimension at the other end.

[0055] The male mold body 2 is fixed to the outer periphery of the base 1, and the male mold body 2 is assembled from multiple male mold blocks 21. For example, as Figure 3 As shown, the male mold body 2 can be a sleeve-like structure, and the male mold assembly 21 can be a cuboid block structure. There are multiple male mold assembly 21s, and the multiple male mold assembly 21s can be arranged in a rectangular array. The male mold body 2 is formed by assembling these arranged male mold assembly 21s.

[0056] The outer periphery of the male mold body 2 is provided with multiple intersecting first rib grooves 22 for the mesh ribs of the compartment 400 to be embedded. The outer periphery of the male mold body 2 includes two opposing edge sides 23. For example, as Figure 3 As shown, the first rib groove 22 can be provided on the outer peripheral wall of the male mold body 2. The multiple first rib grooves 22 can include multiple axial rib grooves that extend along the axial direction of the male mold body 2 and multiple circumferential rib grooves that extend along the circumferential direction of the male mold body 2. The axial rib grooves and circumferential rib grooves can be arranged orthogonally.

[0057] like Figure 3 As shown, the male mold body 2 can be a structure similar to a triangular prism. One edge of the male mold body 2 can be located on the top side, and the other two edges of the male mold body 2 constitute the aforementioned edge side 23. These two edge sides 23 can be arranged opposite each other in the left and right directions, and both edge sides 23 can be arranged to extend along the axial direction of the male mold body 2.

[0058] Two ceramic wood-substitute units 3 are respectively fixed to two edge sides 23, and the two ceramic wood-substitute units 3 are used to break after the compartment 400 is formed to achieve demolding of the male mold 100. For example, as Figure 4 As shown, the ceramic wood substitute unit 3 can be a structure made of ceramic wood substitute material. The ceramic wood substitute unit 3 can be long and narrow, and both ceramic wood substitute units 3 can be arranged to extend along the front and back direction. One ceramic wood substitute unit 3 can be fixed to the left edge side 23 of the male mold body 2 by bolts, etc., and the other ceramic wood substitute unit 3 can be fixed to the right edge side 23 of the male mold body 2 by bolts, etc.

[0059] During the processing of compartment 400, the ceramic wood substitute unit 3 can be located inside compartment 400 and provide support and shaping for the inner side of compartment 400. Because the ceramic wood substitute unit 3 has a certain strength and hardness, it facilitates the forming of the smaller rounded corners of compartment 400 near the edge side 23. After compartment 400 has solidified, when removing the male mold 100 from compartment 400, the ceramic wood substitute unit 3 can be broken, thus facilitating the removal of the male mold 100.

[0060] It should be noted that if steel support mold blocks are used for the two side edges in this application, a single ceramic wood substitute needs to be disassembled into more than 5 pieces, and the connection and positioning accuracy between the 5 pieces cannot guarantee the consistency of mass production. Each of the 5 wood substitutes on both sides requires 100 small steel edges to connect them, which is very complex and has poor precision. However, this application solves this problem well by using ceramic wood substitutes.

[0061] In some embodiments, the base 1 is a tubular structure, and the base 1 is provided with a plurality of fixing points 11, which are respectively used to fix a plurality of male mold blocks 21. For example, Figure 2As shown, the base 1 is a triangular prism tubular structure. Multiple fixing points 11 can be provided on the tube wall of the base 1. These fixing points 11 can be fixing holes that penetrate the base wall along the radial direction of the base 1. In use, bolts can pass through the fixing points 11, allowing the multiple male mold blocks 21 to be fixed to the outer periphery of the base 1, facilitating the installation and fixing of the male mold blocks 21 on the base 1.

[0062] In some embodiments, the base 1 has a triangular cross-section, and the two side edges 23 are arranged opposite to the two side edges of the triangle in the inward and outward directions, respectively. For example, as... Figure 2 As shown, the cross-section of the base 1 can be an isosceles triangle, and the two side edges 23 can correspond to the two base angles of the isosceles triangle in the inner and outer directions, respectively.

[0063] In some embodiments, the male mold block 21 is a steel block, and the ceramic wood substitute unit 3 is a ceramic wood substitute.

[0064] In some embodiments, the plurality of male mold blocks 21 are divided into a plurality of block rings 24 and a plurality of block rows 25. Each block ring 24 includes a plurality of male mold blocks 21 arranged sequentially along the circumference of the base 1, and each block row 25 includes a plurality of male mold blocks 21 arranged sequentially along the axial direction of the base 1.

[0065] For example, such as Figure 5 As shown, the assembly ring 24 can be a ring structure as a whole. The assembly ring 24 can include multiple male mold assembly blocks 21 arranged sequentially in the circumferential direction of the base 1. There can be multiple assembly rings 24. The axial direction of the base 1 can be the front-back direction. Multiple assembly rings 24 can be stacked along the front-back direction, which facilitates the molding of the male mold body 2. Specifically, as shown... Figure 5 As shown in (a) to (b) to (c).

[0066] It should be noted that when multiple interlocking rings 24 are stacked in the front-to-back direction, the multiple male molded interlocking blocks 21 of the multiple interlocking rings 24 can be arranged facing each other in the front-to-back direction. At this time, these interlocking rings 24 that are facing each other in the front-to-back direction can form an interlocking row 25, as shown in the figure below. Figure 5 The portion enclosed by the rectangular dashed box in (c) is shown.

[0067] In some embodiments, a first rib groove 22 is defined between two adjacent patch rings 24 and between two adjacent patch rows 25. For example, as Figure 5As shown, multiple modular rings 24 can be arranged sequentially in the front-to-back direction. A first rib groove 22 can be provided between any two adjacent modular rings 24. This first rib groove 22 can be annular and can be arranged in a circle along the circumference of the male mold body 2. A first rib groove 22 can also be defined between any two modular rows 25, and this first rib groove 22 can extend in the front-to-back direction. In use, a corresponding mesh rib can be placed in each first rib groove 22, thereby forming a crisscrossing mesh rib arrangement, which helps ensure the structural strength of the formed compartment 400.

[0068] In some embodiments, the ceramic wood substitute unit 3 includes a plurality of ceramic wood substitute blocks 31, which are arranged sequentially and connected along the axial direction of the base 1. For example, as Figure 6 As shown, each ceramic wood substitute 31 can be a block structure, and multiple ceramic wood substitute 31 can be sequentially spliced ​​along the front-to-back direction to form a complete ceramic wood substitute unit 3. This facilitates both the processing and shaping of the ceramic wood substitute unit 3 and the adjustment of its overall length, which can be achieved by splicing different numbers of ceramic wood substitute 31.

[0069] In some embodiments, the ceramic wood substitute unit 3 is provided with a plurality of second rib grooves 32 for embedding the mesh ribs. The plurality of second rib grooves 32 are arranged at intervals along the axial direction. The plurality of second rib grooves 32 correspond to and communicate with the first rib grooves 22 that extend circumferentially along the base 1. At least a portion of the second rib grooves 32 are formed between two ceramic wood substitute blocks 31.

[0070] For example, such as Figure 6 As shown, the second rib groove 32 can be provided on the wall surface of the ceramic wood substitute unit 3 facing away from the male mold body 2. The second rib groove 32 can be a rectangular groove. After the ceramic wood substitute unit 3 is spliced ​​and fixed with the male mold body 2, the multiple second rib grooves 32 on the ceramic wood substitute unit 3 can correspond to and be connected with the multiple annular first rib grooves 22 mentioned above, thereby facilitating the formation of a ring of rib grooves on the periphery of the male mold 100, and thus facilitating the arrangement of the annular mesh ribs.

[0071] It should be noted that a portion of the second rib groove 32 can be located between two ceramic wood substitute blocks 31, while another portion of the second rib groove 32 can be located on the wall surface of the ceramic wood substitute block 31 facing away from the positive mold body 2.

[0072] In some embodiments, such as Figure 7 As shown, when the ceramic wood substitute unit 3 is set separately, a portion of the ceramic wood substitute piece 31 is first fixed on the corresponding piece ring 24, and then when multiple piece rings 24 are stacked and fixed, multiple ceramic wood substitute pieces 31 can be assembled into the above-mentioned ceramic wood substitute unit 3.

[0073] In some embodiments, the composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment further includes a first reinforcing frame 4 and a second reinforcing frame 5. The first reinforcing frame 4 is located at one end of the axial direction of the base 1, and one end of the base 1 and one end of the male mold body 2 are both connected to the first reinforcing frame 4. The second reinforcing frame 5 is located at the other end of the axial direction of the base 1, and the other end of the base 1 and the other end of the male mold body 2 are both connected to the second reinforcing frame 5.

[0074] For example, such as Figure 8 As shown, both the first reinforcing frame 4 and the second reinforcing frame 5 can be triangular frames. The first reinforcing frame 4 can be located at the rear end of the base 1, and the second reinforcing frame 5 can be located at the front end of the base 1. The rear end of the male mold body 2 can be connected and fixed to the first reinforcing frame 4 by bolts or the like, and the front end of the male mold body 2 can also be connected and fixed to the second reinforcing frame 5 by bolts or the like. Thus, the connection and fixing strength of the male mold assembly 21 can be strengthened by the first reinforcing frame 4 and the second reinforcing frame 5.

[0075] In some embodiments, the composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment further includes a female mold 200, which is a hollow structure. The female mold 200 is sleeved on the outer periphery of the male mold 100, and a cavity for processing the compartment segment 400 is defined between the male mold 100 and the female mold 200. The female mold 200 is connected between the first reinforcing frame 4 and the second reinforcing frame 5.

[0076] For example, such as Figure 9 As shown, the female mold 200 can be a sleeve structure. In use, the female mold 200 can be fitted onto the outer periphery of the male mold 100, and the annular space between the male mold 100 and the female mold 200 can form a cavity. The front and rear ends of the female mold 200 can be connected and fixed to the corresponding second reinforcing frame 5 and first reinforcing frame 4 respectively by bolts, so that the front and rear sides of the cavity can be sealed by the two reinforcing frames respectively.

[0077] In some embodiments, the female mold 200 includes a plurality of female mold segments 201, which are sequentially connected along the circumference of the male mold 100, and the female mold segments 201 are movable in the inward and outward directions to allow the female mold 200 to float and change during the processing of the chamber 400.

[0078] For example, such as Figure 10 As shown, the female mold 200 may include four or more female mold segments 201. Each female mold segment 201 may be in the shape of a long plate. Each female mold segment 201 may extend along the front-back direction, and multiple female mold segments 201 may be spliced ​​together in the circumferential direction, thereby facilitating the molding of the female mold 200.

[0079] When processing section 400, the male mold 100 can be assembled first. The assembled male mold 100 can be placed in a position such as... Figure 11 and Figure 12 On the rotating bracket 300 shown, multiple mesh ribs can be placed into the corresponding first rib groove 22 and second rib groove 32 of the male mold 100. Then, a skin can be wrapped around the outer periphery of the male mold 100. After the skin is wrapped to the required thickness, the female mold 200 can be placed over the outer periphery of the male mold 100.

[0080] After the material has cured in the furnace, the female mold 200 can be removed first, followed by the removal of the first reinforcing frame 4 or the second reinforcing frame 5. After the base 1 is lifted out, some or all of the male mold pieces 21 can be removed. Finally, the ceramic wood substitute unit 3 can be broken to obtain the desired result. Figure 13 The shown compartment is 400.

[0081] It should be noted that during the heating and curing process, the bolts on the female mold and the two reinforcing frames can be removed, and each female mold segment 201 of the female mold 200 can be guided along the normal direction of the outer contour of the female mold 200 through the corresponding pin. Furthermore, a vacuum pressure is applied to the outside of the female mold 200, thereby enabling the floating and changing position of the female mold 200.

[0082] In some embodiments, two reinforcing frames may be provided on the outer periphery of the middle of the male mold. The two reinforcing frames need to be prepared separately in advance by another mold and semi-cured before being embedded into the male mold of the main body. Subsequently, the mesh ribs and skin are laid on the basis and co-cured. The reinforcing frame is both part of the product and part of the main mold.

[0083] The following describes a specific example of the composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment of this application.

[0084] First, based on the structural characteristics of the irregularly shaped cabin and the required longitudinal and transverse continuity ratio of the mesh reinforcement, P20 thermoplastic mold steel was selected as the primary material for the main body of the male mold, while ceramic-coated wood was chosen as the primary material for the side edges. This avoids the bridging problem caused by the excessive expansion coefficient of aluminum alloy during curing, the inability of silicone rubber to achieve the high longitudinal and transverse continuity ratio of the mesh reinforcement, and the material strength and hardness requirements for the end frame flanges. It also avoids the problem of excessive compression and large radius corners formed by silicone rubber after the mesh reinforcement, transition zone, and skin flanges, which could affect subsequent assembly.

[0085] Secondly, the overall mold structure adopts an assembled steel male mold + floating steel female mold, and achieves heating and pressurization molding through a vacuum autoclave molding process. The mold structure features: the main body of the male mold consists of a carbon steel assembled grid mold + a side-ribbed ceramic substitute wood assembled grid mold, with the forming grid ribs and end frames simultaneously ensuring the inner surface shape; the central part of the male mold uses a traditional modular assembly structure + a side-ribbed ceramic substitute wood mold (disposable), reducing the traditional 60-piece steel mold split structure on each side to 5 ceramic substitute wood molds on each side, solving the problems of excessive steel mold components, inaccurate positioning and connection, and inability to disassemble and demold; facilitating disassembly while avoiding scratches on the product during disassembly. The female mold uses steel blocks to form a floating concave mold, combined with a 2mm carbon fiber process skin plate, and is then vacuum-sealed before pre-pressurization and final curing in an autoclave.

[0086] Thirdly, details of key product components and demolding processes are addressed: The draft angle design for the mesh reinforcement and the radius (R) radius at the cross intersections are treated. Mesh reinforcement demolding follows a 6° angle on one side and a 12° angle on both sides, with a minimum 3° angle on one side based on the reinforcement height. Because it's a cross-shaped mesh reinforcement, the draft angle needs to be slightly larger than a typical single-sided draft angle to ensure reliable demolding. Secondly, the radius (R) radius at the root of the cross intersection is designed according to the requirement of continuous longitudinal and transverse fiber ratio using an equal volume algorithm (specific formula below). Finally, the transition radius between the mesh reinforcement root and the skin area is treated to R2-R3. On the right, the bonding area and bonding force between the mesh reinforcement and the skin are increased to achieve better integrated load-bearing and force transmission of the mesh reinforcement and skin. During the curing process, the axial longitudinal mesh reinforcement and the 0° / ±45° fiber are turned over to the end frame. The metal male mold will expand after heating and the fiber will be affected by tension. Therefore, the end frame part is under tension and turns outward to form an angle greater than the theoretical model. Therefore, in order to ensure the flatness of the end frame and the angle with the skin, it is necessary to prevent the end frame from turning over. The angle deformation of 0.5°-0.8° is compensated in advance by the reverse deformation method, so as to achieve the expected theoretical angle after curing.

[0087] Fourth, thermal expansion matching calculations and verifications of the mold are performed: Due to the high requirements for the product's shape and contour, and its complex irregular structure, the product's expansion in each direction during heating and curing will exhibit non-isotropic proportional elongation due to the asymmetry of the structure. Therefore, thermal expansion and contraction simulations of the product and mold are necessary to accurately calculate the appropriate shrinkage ratio, ensuring that the product achieves the required theoretical shape and dimensional accuracy after curing and demolding. Furthermore, it is necessary to coordinate the matching issue of inconsistent expansion between the ceramic substitute and the steel mold. Because the shell is irregularly shaped, the product's thermal expansion will result in the major axis lengthening and the minor axis shortening due to differences in structural rigidity; therefore, reasonable compensation and shrinkage design are required.

[0088] Fifth, verify the rationality of the mold structure and perform disassembly verification: After the male mold is prepared, assemble the steel mold blocks and ceramic wood substitute blocks, then perform a 3D inspection scan of the mold and compare it with the 3D model of the mold to ensure that the accuracy of the mold meets the theoretical requirements; at the same time, assemble the female mold blocks with the male mold body, and use materials such as clay or feeler gauges to measure whether the gap between the male and female molds is uniform and make timely adjustments. After removing the ceramic wood substitute, lay epoxy resin mesh and then install a reasonable floating female mold (this stage is very critical). Due to the irregular shape of the product, the installation and positioning of the female mold must prevent over-positioning, and issues such as the inability to disassemble the female mold or achieve floating pressure. This is especially critical for the installation of concave curved female mold blocks and side edge female mold blocks. After heating in an oven at 180°C, the male mold blocks are disassembled to verify smooth demolding, the draft angle of the steel mold blocks is set appropriately, the mold seal is reliable to ensure no glue leakage, the contact transition area between the mesh ribs and the skin is reasonable, the mesh rib R at the cross intersections is properly formed, and defects such as insufficient glue, poor glue content, or excessive resin are detected. After verification, the ceramic-wood substitute mold is assembled for preparation before formal laying.

[0089] Based on the rheological properties of the resin, exploring a reasonable curing regime through testing different heating rates is also a key step in ensuring the curing performance of the product. In addition, pre-pressing and adhesive absorption measures before curing are also crucial measures to ensure the interlayer mechanical properties and the expected content ratio of fiber and resin. At the same time, after the first pre-curing before final mold closing, the female mold needs to be removed, and the semi-cured adhesive is pre-treated and a layer of mesh cloth is added to improve the overall appearance quality. This also helps to remove delamination and burrs during subsequent drilling and milling, and prevents stringing, resulting in a higher surface quality.

[0090] The measures taken to address the fifth problem mentioned above are: applying thin adhesive tape between mold blocks to prevent resin loss, and using 0.1-0.2mm mesh fabric as a base layer before layering, which helps to form a better shape during curing and also helps to prevent delamination and burrs during subsequent processing; and using 0.15-0.2mm thick and 30-40mm wide stainless steel skin overlapping between the outer female mold blocks, which helps to prevent resin from entering the gaps between the blocks during curing and causing insufficient resin content and performance degradation in the product. It has been proven that using 0.1mm aluminum alloy or copper alloy between mold blocks is unreasonable. At high temperatures, thin aluminum alloy and copper alloy, due to their low elastic modulus and excessive linear expansion coefficient, will expand first and then shrink, forming wrinkles. The use of 0.1mm stainless steel skin has been verified to be ineffective; even 0.1mm stainless steel itself wrinkles at high temperatures. Finally, using 0.2mm stainless steel skin is feasible, and carbon fiber thin layers should not be used as they are prone to cross-linking with the product during curing, forming unnecessary structures.

[0091] The process of manufacturing the compartments also includes the following three stages: the first stage, the second stage, and the third stage.

[0092] Phase 1: Product 3D Processing

[0093] 1) For the radius rounded corners at the cross intersections of the mesh reinforcement, the fiber longitudinal and transverse continuity ratios should be maintained according to the design requirements, using an equal volume calculation method:

[0094] The formula for calculating the mesh reinforcement R follows the equal volume method: R = C * [L1XL2 / (4-π)]1 / 2;

[0095] Where L1 and L2 are the widths of the longitudinal and transverse mesh reinforcements, respectively, and C is the continuity ratio; when the continuity ratio is 50%, C is 0; when the continuity ratio is 100%, C is 1; when the continuity ratio is 75%, C is 0.75. However, in practice, due to the compression of fibers and resin, the value of C needs to be slightly increased by 10%-20% based on the theoretical calculation of the continuity ratio, making it easier to achieve a better continuity ratio in the process, ensuring fiber continuity and slight bending, thereby preventing fiber breakage. This shell is calculated based on a continuity ratio of 75%.

[0096] The draft angle of the mesh reinforcement is processed, and the draft angle is designed to be 6° on one side;

[0097] The transition radius between the root of the mesh reinforcement and the hull skin is treated with R3 to increase the bonding area and bonding force between the mesh reinforcement and the skin.

[0098] The end frame angle anti-deformation control is designed with an anti-deformation compensation of 0.6° for the shell, which is between 0.5° and 0.8°.

[0099] The root of the inner end face of the end frame and the skin are treated with R3, so as to facilitate the subsequent implementation of 0° / ±45° flanging of the axial mesh reinforcement and skin;

[0100] It ensures that the fibers do not break while providing effective force transmission and load-bearing capacity;

[0101] Phase Two: Mold Design and Expansion Compensation, Non-Proportional Shrinkage Settings in Three Directions

[0102] Perform thermal deformation analysis on the product, compare the expansion of the product before and after heating, and check the temperature at 200°.

[0103] The male mold insert mounting base is integrally cast using Q345 steel. The metal mold insert material is P20 thermoplastic mold steel, and the ceramic substitute material is DM350 (DM450 has been verified to have high hardness and be difficult to break). All female mold inserts are made of P20 steel. The process skin is made of ordinary T300 epoxy resin and 0.2-0.3mm thick carbon fiber fabric, which is laid and cured through the female mold to form a 2mm plate. This plate is used in conjunction with the female mold for pre-pressing the mesh reinforcement and skin. 0.2mm thick, 50mm wide stainless steel plates are used to overlap and seal the gaps between the female mold blocks. The end frames of the female and male molds on both sides are made of P20 material. Thermal deformation analysis of the mold is performed, and the analysis is compared with that of the product.

[0104] The properties of ceramic wood substitutes are as follows: MBT300 ceramic wood substitute: density 0.3, compressive strength 2.5 MPa, linear expansion coefficient 1 x 10⁻⁶. MBT850 ceramic wood substitute: density 0.85, compressive strength 20 MPa, linear expansion coefficient 0.66 x 10⁻⁶.

[0105] To determine the thermal deformation compensation for the mold, the final values ​​for this shell are: height: major axis: minor axis, and the product model of stage one is scaled according to 0.994:0.995:0.996 in the directions of height: major axis: minor axis, respectively.

[0106] The main body of the mold's male mold is designed and then divided into sections; the middle area is divided into sections using metal inserts.

[0107] The two sides are treated as ceramic substitutes for wood, and at the same time, they are used as effective ceramic substitutes for wood inlays. The diameter of the inlays is 5-8mm to reduce the honeycomb holes, and the depth reaches 80% of the thickness of the ceramic substitutes for wood. The hole spacing is controlled at 10-16mm.

[0108] 5) Design the female mold: The female mold is composed of ten ring-shaped pieces joined together; it is connected to the mold end frame by a floating method; the pieces are connected and bridged by stainless steel skin.

[0109] Phase 3: Mold manufacturing, assembly, and testing: (Preparatory treatment before crushing ceramic substitute wood)

[0110] 1) Prepare the male mold insert mounting base, which is precision machined after casting using Q345; manufacture the male mold metal insert, manufacture the ceramic wood substitute insert, make the end frame clamping support frame, and make the female mold insert.

[0111] 2) Install the metal inlays onto the base, install the ceramic substitute wood to form the main structure of the positive mold, and perform three-dimensional scanning and detection;

[0112] 3) Install the end frame clamping support frame on the male mold body;

[0113] 4) Install the female mold inserts one by one, and use a feeler gauge to check the gap between the female mold and the male mold. Check the gap between each female mold and the male mold at no less than 3 points on one side and record the gap data.

[0114] 5) Using female mold inserts, prepare T300 carbon fiber process skin panels;

[0115] 6) After assembling the male and female molds, put them into the autoclave for a mold temperature baseline test. The specific number of sensors should be distributed as follows: no less than 8 points on the windward side and no less than 4 points on each end frame. Perform one heating cycle according to the preset curing regime, and test the mold temperature for subsequent heating regime revision.

[0116] 7) Remove the mold and conduct a demolding test. After cooling, disassemble the female mold pieces, remove the ceramic wood-substitute inlay, and retain the metal inlay male mold main structure. Use epoxy resin fiberglass cloth or high silica cloth to lay the filling mesh and skin, and prepare the skin according to 2mm. After curing in the oven, verify the smoothness of demolding.

[0117] 8) Clean and sanitize the mold. Clean and sanitize the mold inserts, female mold, etc. after the demolding test.

[0118] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0119] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0120] It should be noted that all directional indications in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indications will also change accordingly.

[0121] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0122] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0123] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0124] Furthermore, the technical solutions of the various embodiments can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0125] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A composite mold for ceramic-wood-substitute carbon fiber mesh reinforced shell segment, characterized in that, Includes a male mold, the male mold comprising: Base; The male mold body is fixed to the outer periphery of the base. The male mold body is assembled from multiple male mold blocks. The outer periphery of the male mold body is provided with multiple first rib grooves arranged in a cross pattern for the mesh ribs of the compartment to be embedded. The outer periphery of the male mold body includes two oppositely arranged edge sides. Two ceramic wood substitute units are fixed to the two edge sides respectively, and the two ceramic wood substitute units are used to break after the compartment is formed to achieve demolding of the male mold.

2. The composite mold for ceramic-wood-substitute molding with carbon fiber mesh reinforcement and shell segment according to claim 1, characterized in that, The base is a tubular structure, and multiple fixing points are provided on the base. The multiple fixing points are used to fix multiple male mold blocks respectively.

3. The composite mold for ceramic-wood-substitute molding with carbon fiber mesh reinforcement and shell segment according to claim 1, characterized in that, The base has a triangular cross-section, and the two side edges are respectively arranged opposite to the two side edges of the triangle in the inward and outward directions; And / or, the male mold assembly block is a steel block, and the ceramic wood substitute unit is a ceramic wood substitute.

4. The composite mold for ceramic-wood-substitute molding with carbon fiber mesh reinforcement and shell segment according to claim 1, characterized in that, The plurality of male mold blocks are divided into a plurality of block rings and a plurality of block rows. Each block ring includes a plurality of male mold blocks arranged sequentially along the circumference of the base, and each block row includes a plurality of male mold blocks arranged sequentially along the axial direction of the base.

5. The composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment according to claim 4, characterized in that, The first rib groove is restricted between two adjacent block rings and between two adjacent block rows.

6. The composite mold for ceramic-wood-substitute molding with carbon fiber mesh reinforcement and shell segment according to claim 1, characterized in that, The ceramic wood-substitute unit includes multiple ceramic wood-substitute blocks, which are arranged sequentially and connected along the axial direction of the base.

7. The composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment according to claim 6, characterized in that, The ceramic wood substitute unit is provided with a plurality of second rib grooves for the mesh ribs to be embedded. The plurality of second rib grooves are arranged at intervals along the axial direction. The plurality of second rib grooves correspond to and communicate with the first rib grooves that extend circumferentially along the base among the plurality of first rib grooves, and at least a portion of the second rib grooves are formed between two ceramic wood substitute blocks.

8. The composite mold for ceramic-wood-substitute molding with carbon fiber mesh reinforcement and shell segment according to any one of claims 1-7, characterized in that, Also includes: A first reinforcing frame is disposed at one end of the axial direction of the base, and one end of the base and one end of the male mold body are both connected to the first reinforcing frame; The second reinforcing frame is located at the other end of the axial direction of the base, and the other end of the base and the other end of the male mold body are both connected to the second reinforcing frame.

9. The composite mold for ceramic-wood-substitute molding with carbon fiber mesh reinforcement and shell segment according to claim 8, characterized in that, It also includes a female mold, which is a hollow structure and is fitted around the outer periphery of the male mold. A cavity for processing the compartment is defined between the male mold and the female mold. The female mold is connected between the first reinforcing frame and the second reinforcing frame.

10. The composite mold for ceramic-wood-substitute carbon fiber mesh reinforcement shell segment according to claim 9, characterized in that, The female mold includes multiple female mold segments, which are sequentially connected along the circumference of the male mold, and the female mold segments are movable in the inward and outward directions to allow the female mold to float and change during the processing of the compartment.

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