Large-thickness composite material multi-layer bonding tool and technology

Abstract

The invention relates to the technical field of composite material bonding, in particular to a large-thickness composite material multi-layer bonding tool and process, the large-thickness composite material multi-layer bonding tool is used for assisting bonding of composite material plates, the bonding tool comprises an upper pressing plate and a lower bottom plate which are arranged in parallel, the upper pressing plate and the lower bottom plate are connected through a stand column, and the upper pressing plate is connected with a hydraulic device and used for applying pressure; a first heating plate is arranged on the face, away from the hydraulic device, of the upper pressing plate, and a second heating plate is arranged on the face, away from the hydraulic device, of the lower bottom plate. According to the large-thickness composite material multi-layer bonding tool and process, the bonding face with the uniform roughness is manufactured through treatment of the demolding cloth, the thickness of the adhesive layer is controlled through the glass beads, the upper pressing plate and the lower pressing plate of the tool are provided with the heating plates, the bonding face is rapidly heated and cured, the heating time of a large-thickness product is shortened, and the production efficiency is improved. The problems that the composite material in the middle of the structure is heated unevenly and the curing degree is insufficient are solved, and large-thickness composite material products can be rapidly and effectively manufactured.

Description

Technical Field

[0001] The invention relates to the technical field of composite material bonding, and in particular to a multi-layer bonding tool and process for thick composite materials. Background Art

[0002] For the currently commonly used compression molding composite material process, prepreg is laid, pressurized, heated and cured to form. In theory, thick composite materials can be produced. However, under this process, the heating time of thick products is long, the composite material in the middle of the structure is heated unevenly, the degree of curing is insufficient, and the economic benefit is low. Therefore, it is difficult to manufacture thick composite materials products under this process. Thick composite materials products must be obtained through a multi-layer bonding method.

[0003] At present, composite material bonding is mainly focused on bonding of composite material plates with a small number of layers and a small thickness. The bonding product is relatively thin and the bonding surface treatment method is complicated. There is a great demand for bonding tooling and bonding processes for thick composite materials.

[0004] Publication No.: CN111624066B discloses an auxiliary bonding tool and method for testing out-of-plane tensile tests of three-dimensional woven composite materials. The proposed auxiliary bonding tool uses a sliding limit component to prevent relative slippage between two metal pull blocks and a composite test piece. The sliding limit component includes a limit frame, and the limit frame is provided with a tight limit unit for tightly limiting the two metal pull blocks and the composite test piece. The clamping component provides a clamping force to the composite test piece for the two metal pull blocks, which can prevent the metal pull blocks from being misaligned with the composite test piece and improve the bonding effect. However, the limit component of the invention is composed of a limit frame, and the limit component cannot be adjusted according to the size of the bonded composite material, and the production cost is relatively high; at the same time, the tool cannot be heated and cured, and the conventional heating method cannot meet the bonding quality requirements of thick multi-layer composite materials.

[0005] Therefore, it is urgent to develop new bonding tools and processes to realize the production of thick composite multi-layer bonding products. Summary of the invention

[0006] In view of this, the present invention aims to provide a multi-layer bonding tool and process for thick composite materials, so as to solve the problem that the prior art is difficult to achieve multi-layer bonding of thick composite materials.

[0007] The bonding of composite materials in the prior art is mostly focused on the bonding of a small number of thin-thick composite panels. The thickness of the bonded products is relatively thin, and the common thickness of the panels is as follows: the common thickness range of carbon fiber reinforced materials is 0.1-2.0mm, the common thickness range of glass fiber reinforced materials is 0.5-5.0mm, and in common use scenarios, composite panels generally use 4mm-18mm thick composite panels. In the specific steps of existing composite material bonding and curing, due to the small overall size and thin thickness of the composite panel, the surface is often treated by grinding or chemical methods and then glued, and the bonding is manually positioned. Then, the bonded composite panel is placed in a heating device for heating and curing; or a tool is used to assist in bonding and positioning. The tool is connected to a heating device to wrap the surrounding side of the composite panel for heating. The heat is transferred from the side to the center of the composite panel. The middle position of the single-layer adhesive structure is heated unevenly, which is prone to insufficient curing.

[0008] When using existing composite material board bonding tools and processes to process thick composite material boards, especially for single-layer composite material boards with a thickness range of more than 20mm and multi-layer composite material boards with a thickness of 110-1200mm, the thickness of multi-layer composite materials and the thickness of single layers far exceed the processing range of the existing technology. If manual bonding is used and placed in a heating device for curing, a heating device with a large space is required, the heating time is long, and the cost is very high; if the side limit device with a heating device is used for heating and curing, the heat is transferred from the side to the center of the composite material board. Because the thickness increases, the side heating method prolongs the heating time, and the time interval between the edge and the middle of the single-layer adhesive is prolonged when heating. The uneven heating phenomenon in the middle of the single-layer adhesive structure is more obvious, and the problem of insufficient curing is more serious.

[0009] At the same time, since the working conditions applicable to multi-layer bonding of thick composite materials are different from those of existing thin plate bonding products, higher bonding quality requirements are required. Conventional bonding methods cannot meet the requirements, and it is difficult to manufacture thick composite products. The method of heating the top and bottom of the multi-layer composite material plate makes the heating time between the single layers of adhesive consistent, thereby improving the bonding quality.

[0010] One object of the present invention is to disclose a thick composite material multilayer bonding tool for assisting the bonding of composite material plates, comprising an upper pressing plate, a lower bottom plate, a limiting device, a column and a hydraulic device, wherein the upper pressing plate and the lower bottom plate are arranged in parallel, the upper pressing plate and the lower bottom plate are connected via the column, the column is fixed to the lower bottom plate, the upper pressing plate is connected to the hydraulic device, the hydraulic device is used to apply pressure to the upper pressing plate, the limiting device is used to ensure that the multilayer composite material plates are aligned, the upper pressing plate is provided with a first heating plate, the lower bottom plate is provided with a second heating plate, the first heating plate and the second heating plate are used to heat the composite material plates.

[0011] Furthermore, the upper pressing plate and the first heating plate, and the lower base plate and the second heating plate are connected by screws, bonding or bolts, respectively, and the cross-sectional area of ​​the first heating plate and the second heating plate is larger than the cross-sectional area of ​​the composite material plate.

[0012] Furthermore, the upper pressing plate, the first heating plate and the second heating plate are slidably connected to the columns respectively.

[0013] Furthermore, the upper pressure plate, the first heating plate, the lower base plate and the second heating plate are respectively provided with a first connecting hole, a second connecting hole, a third connecting hole and a fourth connecting hole, the first connecting hole, the second connecting hole and the fourth connecting hole are respectively matched with the column clearance, the third connecting hole is threadedly connected or snap-connected to the column, and one or more of the upper pressure plate, the first heating plate, the lower base plate and the second heating plate are provided with a positioning device, and the positioning device is used to ensure the accurate positioning of the limit device.

[0014] Furthermore, the limiting device includes a baffle and a driving device, a middle portion of one side of the baffle is connected to the driving device, and a side of the baffle away from the driving device is in contact with the composite material plate.

[0015] Furthermore, a baffle limiting block is provided at one end of the baffle, and the baffle limiting block cooperates with the positioning device to form a sliding connection for limiting the displacement of the baffle position.

[0016] Furthermore, the four limiting devices are respectively arranged on the four sides of the composite material plate, the cross-sectional area of ​​the baffle is not larger than the side area of ​​the composite material plate after bonding, and the height difference between the baffle and the composite material plate after bonding is not larger than the thickness of a single composite material plate.

[0017] Another object of the present invention is to disclose a thick composite material multilayer bonding process, based on any thick composite material multilayer bonding tool, comprising the following specific steps:

[0018] S1: Lay release cloth on the surface of prepreg during the molding stage, and remove the release cloth from the composite material board before bonding and place it on a clean operating table;

[0019] S2: Add glass beads to the adhesive and stir evenly;

[0020] S3: Place a composite material board on the lower bottom plate of the bonding tool and align it with the baffle. Use a glue roller to evenly apply the adhesive to the entire bonding surface on its upper surface. Stack another board on the upper side. Repeat this operation until all composite material boards are bonded.

[0021] S4: Control the driving device to move the baffle inwards close to the composite material plate so that all the composite material plates are aligned on all sides;

[0022] S5: Control the upper pressing plate to press down under the action of the hydraulic device;

[0023] S6: Turn on the first heating plate and the second heating plate for heating; raise the temperature to 40-60°C and heat for 4-6 hours;

[0024] S7: After the bonding surface is cured, release the driving device and the hydraulic device to obtain a thick composite material bonding product.

[0025] Furthermore, in step S1, the sizes of the composite material plates are the same, the thickness of the single-layer composite material plate is in the range of 20-90 mm, and the thickness of the multi-layer composite material plate is in the range of 110-1200 mm.

[0026] Furthermore, in step S2, 1‰ glass beads with a diameter of 0.1mm-0.2mm are added to the adhesive and stirred evenly.

[0027] Compared with the prior art, the thick composite material multilayer bonding tool and process of the present invention has the following advantages:

[0028] 1. The present invention sets a multi-layer bonding tool for thick composite materials, adjusts the movement of the baffle and the upper pressure plate, and is suitable for bonding samples of multiple models and multiple layers. The use of a hydraulic press to apply pressure can ensure uniform and controllable pressure. The upper and lower pressure plates of the tool are equipped with heating plates, which can quickly heat up and cure the bonding surface, shorten the heating time of thick products, avoid uneven heating of the composite materials in the middle of the structure, and the problem of insufficient curing, thereby improving economic benefits.

[0029] 2. The present invention manufactures a bonding surface with high surface flatness and uniform roughness by laying a release cloth on the surface of the prepreg during the molding stage, and uses a very small amount of glass beads in the bonding surface to control the thickness of the adhesive layer, thereby achieving rapid and effective manufacturing of thick composite materials and ensuring product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the accompanying drawings:

[0031] Figure 1 It is a schematic diagram of the bonding tool structure of the present invention;

[0032] Figure 2 is a schematic diagram of a composite material plate of the present invention;

[0033] Figure 3 This is a schematic diagram of the lower base structure of the present invention;

[0034] Figure 4 This is a schematic diagram of the baffle structure of the present invention;

[0035] Figure 5 This is a schematic diagram of the structure of the first heating plate of the present invention.

[0036] Description of reference numerals:

[0037] 1. Upper pressure plate; 101. First connecting hole; 2. Lower base plate; 201. Third connecting hole; 3. Limiting device; 301. Baffle; 3012. Baffle limiting block; 302. Driving device; 4. Column; 5. Hydraulic device; 6. Composite material plate; 7. First heating plate; 701. Second connecting hole; 8. Second heating plate; 801. Fourth connecting hole; 802. Groove. DETAILED DESCRIPTION

[0038] In order to make the technical means, objectives and effects of the present invention easy to understand, the embodiments of the present invention are described in detail below with reference to specific drawings.

[0039] It should be noted that all the terms used in the present invention to indicate directionality and position, such as "upper", "lower", "left", "right", "front", "back", "vertical", "horizontal", "inside", "outside", "top", "lower", "lateral", "longitudinal", "center", etc., are only used to explain the relative positional relationship and connection status between the components in a certain state, and are only for the convenience of describing the present invention, rather than requiring the present invention to be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes, and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features.

[0040] In the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 mechanical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0042] The present invention discloses a thick composite material multilayer bonding tool, which is used to assist in the bonding of a composite material plate 6, and includes an upper pressing plate 1, a lower base plate 2, a limiting device 3, a column 4 and a hydraulic device 5. The upper pressing plate 1 and the lower base plate 2 are arranged in parallel, and the upper pressing plate 1 and the lower base plate 2 are connected via the column 4. The column 4 is fixed on the lower base plate 2. The upper pressing plate 1 is connected to the hydraulic device 5 for applying pressure; the limiting device 3 is used to ensure that the multilayer composite material plate 6 is aligned; the upper pressing plate 1 is provided with a first heating plate 7, and the lower base plate 2 is provided with a second heating plate 8. The first heating plate 7 and the second heating plate 8 are used to heat the composite material plate 6.

[0043] The first heating plate 7 and the second heating plate 8 respectively arranged on the upper pressing plate 1 and the lower base plate 2 can provide a uniform heating environment, accelerate the curing reaction of the adhesive, shorten the production cycle, improve production efficiency, avoid uneven heating of the composite material in the middle position of the structure and insufficient curing, and improve economic benefits; the setting of the limiting device 3 effectively ensures the alignment of the multi-layer composite material board 6 during the bonding process, avoiding poor bonding problems caused by misalignment or tilt; through the connection between the upper pressing plate 1 and the hydraulic device 5, the movement of the baffle 301 and the movement of the upper pressing plate 1 are adjusted, and it is suitable for the bonding of multiple models and multiple layers of samples at the same time. The use of the hydraulic device 5 to apply pressure can ensure uniform and controllable pressure; it can achieve uniform and controllable pressure on the multi-layer composite material board 6, which helps to make close contact between the composite material layers, ensure that the adhesive can fully fill the gap, and improve the bonding quality.

[0044] The design structure of the entire tooling is stable and can withstand large pressure and temperature changes, and has high stability and reliability. By applying uniform pressure and ensuring the alignment and heating curing of the multilayer composite material plate 6, the quality and durability of the bonded joint can be significantly improved, the curing time of the adhesive can be shortened, the operation is simple, and the production efficiency is improved.

[0045] Preferably, a first heating plate 7 is disposed on a surface of the upper pressing plate 1 away from the hydraulic device 5 , and a second heating plate 8 is disposed on a surface of the lower base plate 2 away from the hydraulic device 5 .

[0046] The arrangement of the first heating plate 7 and the second heating plate 8 in direct contact with the composite material plate 6 helps to improve heat transfer efficiency, reduce energy consumption, shorten heating time, and improve bonding efficiency.

[0047] Specifically, the hydraulic device 5 is a hydraulic press, and the pressurizing pressure can be adjusted by controlling the hydraulic press.

[0048] The hydraulic device 5 can adjust the pressurizing pressure according to the needs of different composite panels 6 and multilayer composite panels 6. By reasonably selecting the pressurizing pressure, sufficient penetration of the resin, interlayer bonding strength, material density and uniformity of the curing process can be ensured.

[0049] The correct pressurization pressure can not only improve the quality of the product, but also optimize production efficiency and ensure the reliability and consistency of the final product. In practical applications, it is necessary to comprehensively consider factors such as material properties, product thickness, resin type and curing conditions to select the most appropriate pressurization pressure.

[0050] Specifically, the upper pressing plate 1 is connected to the first heating plate 7 by screws, bonding or bolts, and the cross-sectional area of ​​the first heating plate 7 is larger than the cross-sectional area of ​​the composite material plate 6 .

[0051] Whether it is screw, adhesive or bolt connection, it can ensure the firm connection between the upper pressure plate 1 and the first heating plate 7, effectively transmit pressure, maintain heating uniformity, and ensure the stability of the tooling during operation; at the same time, when the heating plate is damaged or needs to be replaced, it can be easily disassembled and replaced, reducing maintenance costs and time; a variety of connection methods can be selected according to specific working conditions and needs to adapt to different working environments and conditions.

[0052] The cross-sectional area of ​​the first heating plate 7 is larger than the cross-sectional area of ​​the composite material plate 6, which can ensure that heat can be evenly transferred to various parts of the composite material plate 6 during the heating process, avoiding local overheating or uneven temperature, and helping to evenly cure the adhesive, thereby improving the quality and durability of the bonded joint.

[0053] This setting helps to improve the overall stability and heating uniformity of the tooling, is easy to repair and replace, has strong adaptability, and can effectively improve the quality of the bonded joint.

[0054] Preferably, the cross section of the first heating plate 7 is rectangular.

[0055] This arrangement facilitates the manufacture of the first heating plate 7 , reduces production cost and time, makes it easier to position and fix during installation, and ensures accurate matching with the upper pressing plate 1 .

[0056] Specifically, the lower base plate 2 is connected to the second heating plate 8 by screws, bonding or bolts, and the cross-sectional area of ​​the second heating plate 8 is larger than the cross-sectional area of ​​the composite material plate 6 .

[0057] This setting helps to improve the overall stability and heating uniformity of the tooling, is easy to repair and replace, has strong adaptability, and can effectively improve the quality of the bonded joint.

[0058] Preferably, the cross section of the second heating plate 8 is square.

[0059] This arrangement facilitates the manufacture of the first heating plate 7 , reduces production cost and time, makes it easier to position and fix during installation, and ensures accurate matching with the upper pressing plate 1 .

[0060] Specifically, the upper pressing plate 1 , the first heating plate 7 , the lower bottom plate 2 and the second heating plate 8 are slidably connected to the pillars 4 , respectively.

[0061] The sliding connection arrangement allows the upper pressing plate 1, the first heating plate 7, the lower bottom plate 2 and the second heating plate 8 to move up and down on the column 4, so that the tooling can adapt to composite material panels 6 of different thicknesses without replacing the entire tooling, thereby improving the convenience and efficiency of use, ensuring that the upper pressing plate 1, the first heating plate 7, the lower bottom plate 2 and the second heating plate 8 are on the same axis, can better withstand pressure, achieve uniform distribution of pressure, ensure that each layer of composite material panels 6 is heated evenly, and improve the bonding quality.

[0062] Preferably, the cross-sections of the upper pressing plate 1 , the first heating plate 7 , the lower bottom plate 2 and the second heating plate 8 are rectangular, and the four corners of the upper pressing plate 1 , the first heating plate 7 , the lower bottom plate 2 and the second heating plate 8 are all slidably connected to the column 4 .

[0063] This arrangement enables the upper pressing plate 1 and the first heating plate 7 to move more stably on the pillar 4, achieves more precise positioning, avoids eccentric pressurization, and improves bonding quality.

[0064] Specifically, the cross section of the column 4 is square or circular.

[0065] The arrangement of the upright column 4 has a simple structure and is convenient and quick to manufacture, thus reducing the difficulty of manufacture and being conducive to reducing production costs.

[0066] Specifically, the upper pressing plate 1, the first heating plate 7, the lower bottom plate 2 and the second heating plate 8 are respectively provided with a first connecting hole 101, a second connecting hole 701, a third connecting hole 201 and a fourth connecting hole 801, the first connecting hole 101, the second connecting hole 701 and the fourth connecting hole 801 are respectively loosely matched with the column 4, the third connecting hole 201 is threadedly connected or snap-connected to the column 4, and a positioning device is provided on one or more of the upper pressing plate 1, the first heating plate 7, the lower bottom plate 2 and the second heating plate 8, and the positioning device is used to ensure the accurate positioning of the limiting device 3.

[0067] The first connecting hole 101, the second connecting hole 701 and the fourth connecting hole 801 are respectively clearance-matched with the column 4 to ensure the precise positioning of each component during the sliding process. The third connecting hole 201 is threadedly connected or clamped to the column 4 to ensure the stability of the column 4 and avoid the occurrence of misalignment and tilting, thereby improving the accuracy and quality of bonding; the clearance-matching design reduces the friction resistance of each component during the sliding process, making the operation smoother, while also reducing the heat and wear generated by friction, extending the service life of the tooling, and facilitating the disassembly and replacement of each component, simplifying the maintenance process of the tooling, reducing the difficulty of processing tooling parts, and reducing production and maintenance costs; the positioning device can ensure that the limit device 3 is in a fixed position, ensuring that the position of the limit device 3 does not move during product processing, avoiding the phenomenon that the upper and lower plates of the composite material plate 6 are not aligned, affecting the bonding quality.

[0068] Specifically, the positioning device is arranged on the surface of the second heating plate 8 away from the lower bottom plate 2 , and the positioning device is a groove 802 , which is used to limit the displacement of the limiting device 3 .

[0069] The positioning device is arranged on the second heating plate 8, which is convenient for fixing the limiting device 3 and helps to improve the overall stability and reliability of the device. Moreover, the positioning device has a simple structure and is easy to process and produce, which helps to reduce production costs and improve the stability of the device.

[0070] Specifically, the limiting device 3 is provided with a plurality of limiting plates, and the plurality of limiting plates can move simultaneously to align the composite material plates 6 .

[0071] The plurality of limit plates move simultaneously under the action of the same power source and act on the four sides of the composite material plate 6 at the same time to align them.

[0072] The setting of the limiting device 3 only requires a single power source, which reduces the equipment investment cost and is conducive to the popularization and use of the bonding device.

[0073] Specifically, the limiting device 3 includes a baffle 301 and a driving device 302 . The middle of one side of the baffle 301 is connected to the driving device 302 . One side of the baffle 301 away from the driving device 302 is in contact with the composite material plate 6 . A plurality of limiting devices 3 are provided.

[0074] The baffle 301 is a main limiting component, which contacts the side of the composite material plate 6 to prevent it from shifting or tilting during the bonding process.

[0075] The driving device 302 provides power for the limiting device 3, so that the baffle 301 moves closer to or farther from the composite material plate 6, so as to adapt to composite material plates 6 of different thicknesses and ensure that the limiting function is effectively exerted.

[0076] Providing a plurality of limiting devices 3 can limit the composite material plate 6 from multiple directions to prevent it from deflecting.

[0077] This setting ensures the precise alignment of the multilayer composite material panels 6 during the bonding process, can adapt to composite material panels 6 of different thicknesses and sizes, improves the quality and precision of the bonding joints, is simple and quick to operate and adjust, and reduces the skill requirements for the operator.

[0078] Preferably, a baffle limit block 3012 is provided at one end of the baffle 301 adjacent to the second heating plate 8 , and the baffle limit block 3012 cooperates with the groove 802 to form a sliding connection for limiting the displacement of the position of the baffle 301 .

[0079] The baffle limit block 3012 is provided to form a sliding connection with the groove 802, which not only limits the position of the baffle 301 to prevent unnecessary displacement during operation, but also ensures the accuracy and stability of the limit.

[0080] Preferably, four limiting devices 3 are provided, and the four limiting devices 3 are respectively provided on four sides of the composite material plate 6 .

[0081] Four limiting devices 3 are provided, which are respectively located on the four sides of the composite material plate 6, so as to ensure that the composite material plate 6 is limited from all directions, so that the composite material plate 6 is aligned as a whole and prevented from being offset in any direction.

[0082] Specifically, the driving device 302 may be electrically driven or hydraulically driven.

[0083] The drive device 302 is provided to provide power for the limiting device 3 and can be electrically or hydraulically driven, and a suitable power source can be selected according to different working environments and requirements.

[0084] Specifically, the limiting device 3 is arranged in the middle between the upper pressing plate 1 and the lower bottom plate 2 , and the limiting device 3 is arranged on the symmetry axis of the side surface of the lower bottom plate 2 .

[0085] This arrangement limits the installation position of the limiting device 3, so that the limiting effect can be more balanced and stable, avoiding the problem of uneven force caused by position offset.

[0086] Specifically, the cross-sectional area of ​​the baffle 301 is not greater than the side area of ​​the composite material plate 6 after bonding, and the height difference between the baffle 301 and the composite material plate 6 after bonding is not greater than the thickness of a single composite material plate.

[0087] The cross-sectional area of ​​the baffle 301 is not larger than the side area of ​​the composite material plate 6 after bonding, which ensures that the baffle 301 can fit tightly against the side of the composite material plate 6, thereby effectively preventing it from shifting or tilting during the pasting process, and avoiding interference with other parts of the tooling, which would affect the smooth progress of the bonding process.

[0088] The height difference between the baffle 301 and the composite material plate 6 after bonding is no greater than the thickness of a single composite material plate, which helps to ensure that when pressure is applied, the pressure can be evenly transmitted to all parts of the composite material, helps to improve the quality and durability of the bonded joint, and prevents excessive pressure from being applied locally when the area of ​​the baffle 301 is too small, thereby causing loss or deformation.

[0089] This arrangement enables the shape centers of the multi-layer composite panels 6 to be on the same axis, so that the multi-layer panels are simultaneously applied to the sides of all composite panels 6 under the action of the limiting device 3, ensuring that all composite panels 6 are aligned up and down, avoiding lateral slippage, resulting in differences in the bonding surface areas between layers, causing uneven distribution of glue and affecting the curing effect, improving the stability and applicability of the tooling, and ensuring the smooth progress of the bonding process and the high quality of the bonding joints.

[0090] Specifically, the upper pressing plate 1 , the lower base plate 2 , the column 4 , the first heating plate 7 , the second heating plate 8 and the baffle 301 are all made of steel.

[0091] The parts and components of this device have a wide range of sources, are relatively low in price, and are easy to process and produce, which helps to reduce the production cost of the device.

[0092] A thick composite material multilayer bonding process, based on any thick composite material multilayer bonding tool, comprises the following specific steps:

[0093] S1: Lay a release cloth on the surface of the prepreg during the molding stage, and remove the release cloth from the composite material plate 6 before bonding and place it on a clean operating table;

[0094] S2: Add glass beads to the adhesive and stir evenly;

[0095] S3: Place a composite material plate 6 on the lower bottom plate 2 of the bonding tool and align it with the baffle 301, use a glue roller to evenly apply the adhesive to the entire bonding surface on its upper surface, take another piece and stack it on the upper side, and repeat this operation until all composite material plates 6 are bonded;

[0096] S4: Control the driving device 302 to move the baffle 301 inwardly close to the composite material plate 6 so that all the composite material plates 6 are aligned on all sides;

[0097] S5: Control the upper pressing plate 1 to press downward under the action of the hydraulic device 5;

[0098] S6: Turn on the first heating plate 7 and the second heating plate 8 for heating;

[0099] S7: After the bonding surface is solidified, the driving device 302 and the hydraulic device 5 are released to obtain a thick composite material bonding product.

[0100] By means of demoulding cloth treatment, adhesive configuration, gluing, alignment of multi-layer composite material plates 6, pressurization and heating curing, multi-layer bonding of thick composite materials is achieved to form a stable and reliable structure; adding glass beads to the adhesive helps to enhance the peeling strength of the bonding surface and at the same time improve the roughness of the bonding surface, thereby increasing the adhesion between layers; by controlling the driving device 302, the baffle 301 is moved inwardly close to the composite material plate 6 to ensure that all composite material plates 6 are aligned on all sides during the bonding process, thereby ensuring the consistency and accuracy of the multi-layer composite material structure; applying pressure using the upper pressing plate 1 can ensure that the distance between layers and the amount of adhesive are the same, which helps to improve the curing effect; using the first heating plate 7 and the second heating plate 8 to heat the multi-layer composite material can effectively promote the curing speed, and using a plate-shaped heating device to heat the composite material plate 6 can avoid the problem of uneven heating in the middle and edges of the plate caused by side heating in the prior art, which in turn affects the curing effect.

[0101] The tooling for multi-layer bonding of thick composite materials is set up, the movement of the baffle 301 and the upper pressing plate 1 are adjusted, and it is suitable for bonding of samples of multiple models and multiple layers at the same time. The use of a hydraulic press to apply pressure can ensure that the pressure is uniform and controllable. The upper and lower pressing plates of the tooling are equipped with heating plates, which can quickly heat up and cure the bonding surface, shorten the heating time of thick products, avoid uneven heating of composite materials in the middle position of the structure, and insufficient curing, thereby improving economic benefits. A bonding surface with high surface flatness and uniform roughness is manufactured by laying a release cloth on the surface of the prepreg during the molding stage, and a very small amount of glass beads is used in the bonding surface to control the thickness of the adhesive layer, so that thick composite products can be quickly and effectively manufactured, and the bonding quality of the products can be guaranteed.

[0102] Specifically, the thickness of the single-layer composite material plate 6 is not less than 20 mm.

[0103] The setting that the thickness of the single-layer composite material plate 6 is not less than 20mm has higher requirements for the bonding quality of the multi-layer composite material plate. Because the thickness increases, the side heating method prolongs the heating time, and the time interval between the edge and the middle of the single-layer adhesive is prolonged when heating, the uneven heating is aggravated, and the degree of curing is insufficient. The method of heating the top and bottom of the multi-layer composite material plate 6 makes the heating time between the single-layer adhesive consistent, and the bonding quality can be improved regardless of whether the composite material plate 6 has the same or different thickness. The shape center of the multi-layer composite material plate 6 can be on the same axis, so that the multi-layer plate is applied to the side of all the composite material plates 6 at the same time under the action of the limiting device 3, ensuring that all the composite material plates 6 are aligned up and down, avoiding lateral slippage, resulting in differences in the bonding surface area between layers, causing uneven distribution of glue and affecting the curing effect.

[0104] Preferably, the thickness of the single-layer composite material plate 6 is not less than 100 mm.

[0105] When the thickness of the single-layer composite material plate 6 is not less than 100 mm, the side heating method prolongs the heating time significantly due to the thicker thickness. The time interval between the edge and the middle of the single-layer adhesive is prolonged during heating, the uneven heating is aggravated, and the degree of curing is insufficient. The upper and lower surfaces of the multi-layer composite material plate 6 are heated so that the heating time between the single-layer adhesives is consistent, thereby improving the bonding quality.

[0106] Preferably, in step S1 , the composite material plates 6 have the same size, the thickness of the single-layer composite material plate 6 is in the range of 20-90 mm, and the thickness of the multi-layer composite material plate 6 is in the range of 110-1200 mm.

[0107] The thickness range of the single-layer composite material plate 6 is 20-90mm, which has higher requirements for the bonding quality of the multi-layer composite material plate. Because the thickness increases, the side heating method prolongs the heating time, the time interval between the edge and the middle of the single-layer adhesive is prolonged when heating, the uneven heating is aggravated, and the curing degree is insufficient. The method of heating the upper and lower sides of the multi-layer composite material plate 6 makes the heating time between the single-layer adhesive consistent, which improves the bonding quality. The shape center of the multi-layer composite material plate 6 can be on the same axis, so that the multi-layer plate is applied to the side of all composite material plates 6 at the same time under the action of the limit device 3, ensuring that all composite material plates 6 are aligned up and down, avoiding lateral slippage, resulting in differences in the bonding surface area between layers, causing uneven distribution of glue and affecting the curing effect; the multi-layer composite material plate has a large total thickness and can withstand large external forces and loads, so it has a high structural strength and can be used in fields that require high strength. The multi-layer design can further disperse stress and reduce stress concentration, which is convenient for flexible selection of the appropriate number of layers according to actual use conditions to meet the needs of different scenarios.

[0108] The multi-layer composite material plate 6 has strong structural strength and excellent fatigue resistance. By adjusting the number of layers and the thickness of each layer, it is convenient to design according to actual conditions. At the same time, the standardized single-layer composite plate helps to quickly process and install, reduce processing difficulty and cost, and maximize material utilization and production efficiency.

[0109] Preferably, the thickness of the single-layer composite material plate 6 is in the range of 90-100 mm.

[0110] The thickness range of the single-layer composite material plate 6 is greatly different from the thickness range of the existing multi-layer composite material plate bonding. Because the thickness increases, the side heating method prolongs the heating time, and the time interval between the edge and the middle of the single-layer adhesive is prolonged when heating, which aggravates the uneven heating and causes insufficient curing. The method of heating the upper and lower surfaces of the multi-layer composite material plate 6 makes the heating time between the single-layer adhesive consistent, thereby improving the bonding quality. At the same time, the composite material plate 6 within this range is more convenient and quick to transport and install, which is helpful for on-site production.

[0111] Specifically, in step S2, 1‰ glass beads with a diameter of 0.1mm-0.2mm are added to the adhesive and stirred evenly.

[0112] Glass beads are added to adhesives as fillers to increase the roughness of the bonding surface, help control the thickness of the adhesive layer, and improve the mechanical bite force between the adhesive and the composite surface, thereby enhancing the bonding strength; at the same time, glass beads play a role in dispersing stress in the adhesive layer, which helps to reduce stress concentration, improve the durability of the bonded joint, reduce the amount of adhesive used, and reduce costs.

[0113] This setup can achieve adhesive modification through simple mixing operations, improve production efficiency, and control the performance of the bonded joint by adjusting the addition and particle size of glass microspheres.

[0114] Specifically, in step S5, the pressing pressure of the hydraulic device 5 reaches 30 Kpa.

[0115] The downward pressure of the hydraulic device 5 reaches 30Kpa, which can ensure close contact between the layers of the composite material plate 6 and between the composite material plate 6 and the bonding tooling, discharge bubbles and gaps, and improve the bonding quality; under the action of pressure, the adhesive can better fill the tiny gaps and irregularities on the surface of the composite material to form a more uniform bonding layer; during the pressurization process, the interaction force between the layers of the composite material and between the layers and the tooling is enhanced, which helps to improve the stability and bearing capacity of the overall structure.

[0116] The arrangement uses the hydraulic device 5, which has stable pressure output, can realize precise control of the pressurization process, is easy to operate, and has good repeatability of the pressurization effect, which is conducive to ensuring the consistency of product quality.

[0117] Specifically, in step S6, the first heating plate 7 and the second heating plate 8 are heated to 40-60°C for 4-6 hours.

[0118] Preferably, the first heating plate 7 and the second heating plate 8 are heated to 50° C. for 5 hours.

[0119] Heating can accelerate the chemical reaction rate in the adhesive, shorten the curing time and improve production efficiency; appropriate heating temperature can promote the chemical bonding between the adhesive and the surface of the composite material, improve the bonding strength and durability; during the heating and curing process, the adhesive gradually changes from liquid to solid, and the volume shrinkage and stress release process are more uniform and controllable, which helps to reduce the generation of internal stress and cracks.

[0120] This setting can achieve high efficiency and energy saving while ensuring the bonding quality by precisely controlling the heating temperature and time. Precisely controlled temperature and time help to ensure the stability and consistency of product quality. It is suitable for many types of adhesives and composite materials.

[0121] Example 1

[0122] Remove the release cloth from the composite material plates 6 of the same size and place them on a clean operating table; add 1‰ glass beads with a diameter of 0.1mm-0.2mm to the adhesive and stir evenly; place a composite material plate 6 on the bonding tool and align the plate with the baffle 301, use a glue roller to evenly apply the adhesive to the entire bonding surface on its upper surface, and stack another piece on the upper side; repeat this operation until all composite material plates 6 are bonded; control the drive device 302 to move the baffle 301 inward so that all composite material plates 6 are aligned on all sides; control the hydraulic device 5 of the upper pressing plate 1 to descend until the pressure reaches 30Kpa. Turn on the first heating plate 7 and the second heating plate 8 to heat, raise the temperature to 50℃, and heat for 5 hours to accelerate the curing speed of the bonding surface; after the bonding surface is cured, release the drive device 302 and the hydraulic device 5 to obtain a thick composite material bonding product.

[0123] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A thick composite material multilayer bonding tool, used for assisting the bonding of composite material plates (6), comprising an upper pressing plate (1), a lower base plate (2), a limiting device (3), a column (4) and a hydraulic device (5), wherein the upper pressing plate (1) and the lower base plate (2) are arranged in parallel, the upper pressing plate (1) and the lower base plate (2) are connected via the column (4), the column (4) is fixed on the lower base plate (2), the upper pressing plate (1) is connected to the hydraulic device (5), the hydraulic device (5) is used to apply pressure to the upper pressing plate (1), the limiting device (3) is used to ensure that the multilayer composite material plates (6) are aligned, and is characterized in that: The upper pressing plate (1) is provided with a first heating plate (7), and the lower base plate (2) is provided with a second heating plate (8), and the first heating plate (7) and the second heating plate (8) are used to heat the composite material plate (6).

2. The thick composite material multilayer bonding tool according to claim 1, characterized in that: The upper pressing plate (1) and the first heating plate (7), and the lower base plate (2) and the second heating plate (8) are connected by screws, bonding or bolts, and the cross-sectional areas of the first heating plate (7) and the second heating plate (8) are both larger than the cross-sectional area of ​​the composite material plate (6).

3. The thick composite material multilayer bonding tool according to claim 1, characterized in that: The upper pressing plate (1), the first heating plate (7) and the second heating plate (8) are respectively slidably connected to the upright column (4).

4. The thick composite material multilayer bonding tool according to claim 3, characterized in that: The upper pressing plate (1), the first heating plate (7), the lower bottom plate (2) and the second heating plate (8) are respectively provided with a first connecting hole (101), a second connecting hole (701), a third connecting hole (201) and a fourth connecting hole (801); the first connecting hole (101), the second connecting hole (701) and the fourth connecting hole (801) are respectively loosely matched with the column (4); the third connecting hole (201) is threadedly connected or snap-connected to the column (4); one or more of the upper pressing plate (1), the first heating plate (7), the lower bottom plate (2) and the second heating plate (8) are provided with a positioning device, and the positioning device is used to ensure the accurate positioning of the limiting device (3).

5. The thick composite material multilayer bonding tool according to claim 4, characterized in that: The limiting device (3) comprises a baffle (301) and a driving device (302); the middle portion of one side of the baffle (301) is connected to the driving device (302); and the side of the baffle (301) away from the driving device (302) is in contact with the composite material plate (6).

6. The thick composite material multilayer bonding tool according to claim 5, characterized in that: A baffle limiting block (3012) is provided at one end of the baffle (301), and the baffle limiting block (3012) cooperates with the positioning device to form a sliding connection, so as to limit the displacement of the position of the baffle (301).

7. The thick composite material multilayer bonding tool according to claim 5, characterized in that: The four limiting devices (3) are respectively arranged on the four sides of the composite material plate (6); the cross-sectional area of ​​the baffle (301) is not greater than the side area of ​​the composite material plate (6) after bonding; and the height difference between the baffle (301) and the multiple layers of the composite material plate (6) is not greater than the thickness of a single composite material plate.

8. A multi-layer bonding process for thick composite materials, characterized in that: The thick composite material multilayer bonding tool according to any one of claims 1 to 7 comprises the following specific steps: S1: Laying a release cloth on the surface of the prepreg during the molding stage, and before bonding, removing the release cloth from the composite material plate (6) and placing it on a clean operating table; S2: Add glass beads to the adhesive and stir evenly; S3: Place a composite material plate (6) on the lower bottom plate (2) of the bonding tool and align it with the baffle (301), use a glue roller to evenly apply adhesive to the entire bonding surface on its upper surface, take another plate and stack it on the upper side, and repeat this operation until all composite material plates (6) are bonded; S4: controlling the driving device (302) to move the baffle (301) inwardly close to the composite material plate (6) so that all the composite material plates (6) are aligned on all sides; S5: Controlling the upper pressing plate (1) to press downward under the action of the hydraulic device (5); S6: Turn on the first heating plate (7) and the second heating plate (8) for heating; raise the temperature to 40-60° C. and heat for 4-6 hours; S7: After the bonding surface is solidified, the driving device (302) and the hydraulic device (5) are released to obtain a composite material bonding product with a large thickness.

9. The multi-layer bonding process of thick composite materials according to claim 8, characterized in that: In step S1, the composite material plates (6) have the same size, the thickness of the single-layer composite material plate (6) is in the range of 20-90 mm, and the thickness of the multi-layer composite material plate (6) is in the range of 110-1200 mm.

10. The multi-layer bonding process of thick composite materials according to claim 8, characterized in that: In step S2, 1‰ glass beads with a diameter of 0.1mm-0.2mm are added to the adhesive and stirred evenly.

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