Carbon fiber composite board
By using metal rivets to weld metal plates to carbon fiber composite panels, the problems of poor load transfer and high precision requirements of existing connection methods are solved, achieving efficient fixing and low-cost production suitable for appearance parts.
Patent Information
- Application Number
- CN202422824721.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-20
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-11-20
AI Technical Summary
Existing carbon fiber composite material joining methods suffer from problems such as poor load transfer, complex processes, high precision requirements, high costs, and unsuitability for appearance parts.
The structure uses metal rivets that pass through pre-drilled holes in the carbon fiber plate and are welded to the metal plate, which simplifies the connection process, avoids pre-embedding and surface treatment, and is suitable for production in ordinary welding workshops.
It achieves a firm fixation between carbon fiber plates and metal plates, is suitable for appearance parts, reduces operation and precision requirements, is suitable for industrial production, reduces protrusions, and lowers production costs.
Smart Images
Figure CN223494033U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of composite materials technology, and in particular to a carbon fiber composite plate. Background Technology
[0002] Due to limitations in materials and manufacturing processes, carbon fiber composite materials often employ traditional connection methods for their components, resulting in ineffective load transfer. Currently, commonly used connection methods include mechanical connections, blind riveting, adhesive bonding, and hybrid connections.
[0003] For adhesive bonding, the bonding surfaces require special treatment, and the process is subject to strict requirements.
[0004] Mechanical connection methods include using fasteners, which requires pre-embedding metal nuts in the carbon fiber sheet and then bolting them together through holes drilled in the metal sheet. Alternatively, holes can be pre-drilled in both the carbon fiber and metal sheets, allowing direct connection with bolts and nuts. However, the fastener connection method requires a certain thickness of carbon fiber to accommodate the metal nuts, and this process necessitates pre-assembly during carbon fiber molding, demanding high operational precision and resulting in low efficiency. Furthermore, the exposed fastener portions on both sides of the connected sheet create a noticeable protrusion, making this method unsuitable for connecting exterior parts.
[0005] Mechanical connection methods also include blind riveting, which requires pre-drilling holes in the carbon fiber and metal sheets, demanding high drilling precision. Furthermore, if the assembly precision is insufficient during use, misalignment of the upper and lower holes will prevent connection, increasing the difficulty for workers. After riveting the upper and lower plates together, the exposed rivets on both sides of the plates create a protrusion of a certain height, meaning this process is not suitable for connecting exterior parts.
[0006] Due to the unique processing and bonding characteristics of carbon fiber, it is usually difficult to perform welding production using existing welding equipment in the OEM workshop. Dedicated production lines are often required for production and assembly, which necessitates significant investment in cost, production cycle, and quality control. Utility Model Content
[0007] In view of this, the present application provides a carbon fiber composite plate to solve the problems existing in the connection methods of carbon fiber composite materials in the background art.
[0008] This application provides a carbon fiber composite plate, comprising:
[0009] A carbon fiber plate having a plurality of first pre-formed holes extending along the thickness direction of the carbon fiber plate.
[0010] A metal plate, the metal plate being located on the first side of the carbon fiber plate and being in contact with the first side of the carbon fiber plate;
[0011] A plurality of metal rivets, each rivet comprising a head and a shank; the shank is located within a first pre-drilled hole, one end of the shank is fixed to the head, and the other end is welded to the metal plate; the head presses against a second side of the carbon fiber plate, the second side being the opposite side to the first side.
[0012] In an optional embodiment, the carbon fiber composite plate further includes a gasket with a second pre-formed hole, the gasket being sleeved on the nail rod and located between the nail head and the carbon fiber plate body.
[0013] In an optional embodiment, the gasket is a glass fiber gasket.
[0014] In an optional embodiment, the nail bar includes a nail bar body and a recessed section, the recessed section being located at the end of the nail bar body near the nail head, the maximum diameter of the recessed section being equal to the diameter of the nail bar body, and the minimum diameter of the recessed section being smaller than the diameter of the nail bar body;
[0015] The gasket is fitted onto the recessed section, and the inner diameter of the second pre-drilled hole matches the diameter of the recessed section.
[0016] In an optional embodiment, the total thickness of the nail head and the washer is less than 1 mm.
[0017] In an optional embodiment, the thickness of the gasket is less than 0.2 mm.
[0018] In an optional embodiment, the thickness of the nail head is less than 0.8 mm.
[0019] In an optional embodiment, the first pre-drilled hole is interference-fitted with the nail rod.
[0020] In an optional embodiment, the diameter of the nail head is 16mm to 20mm.
[0021] In an alternative embodiment, the metal rivets and the metal plate are made of the same material.
[0022] The carbon fiber composite plate provided in this application uses a structure where metal rivets pass through a first pre-drilled hole in the carbon fiber plate and are welded to the metal plate to fix the carbon fiber plate and the metal plate. This eliminates the need for any pre-embedding or surface treatment, resulting in a simple structure. The only tool required is welding equipment, making it easy to manufacture and assemble in a standard welding workshop. The carbon fiber composite plate has rivet heads only on one side, with no protrusions on the other, making it suitable for exterior parts. The process does not rely on holes in the metal plate, and there is no need to align the holes during assembly; therefore, the requirements for operation and precision are not high, making it suitable for industrialization.
[0023] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description
[0024] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:
[0025] Figure 1 This is a schematic diagram of the cross-sectional structure of the carbon fiber composite plate provided in the embodiments of this application;
[0026] Figure 2 This is a schematic diagram of the preliminary assembly state of the metal rivets provided in the embodiments of this application;
[0027] Figure 3 This is a schematic diagram of the state of a metal rivet after welding, provided in an embodiment of this application.
[0028] Figure 4 This is a schematic diagram of the metal rivet and washer connection structure provided in an embodiment of this application;
[0029] Figure 5 This is a schematic diagram of the structure of the first carbon fiber composite plate in the prior art;
[0030] Figure 6 This is a schematic diagram of the structure of the second type of carbon fiber composite plate in the prior art;
[0031] Figure 7 This is a schematic diagram of the structure of the third type of carbon fiber composite plate in the prior art.
[0032] The attached figures are labeled as follows:
[0033] 1. Carbon fiber plate; 11. First pre-fabricated hole;
[0034] 2. Metal plate;
[0035] 3. Metal rivet; 31. Rivet head; 32. Rivet shank; 33. Weld nugget; 321. Rivet shank body; 322. Recessed section;
[0036] 4. Gasket; 41. Second pre-drilled hole;
[0037] 5. Screws;
[0038] 6. Protective layer;
[0039] 7. Inlays;
[0040] 8. Bolts;
[0041] 100, upper electrode; 200, lower electrode. Detailed Implementation
[0042] To make the technical solution and beneficial effects of this utility model more apparent and understandable, a detailed description is provided below by listing specific embodiments. The accompanying drawings are not necessarily drawn to scale, and local features may be enlarged or reduced to more clearly show the details of the local features; unless otherwise defined, the technical and scientific terms used herein have the same meanings as those in the technical field to which this application pertains.
[0043] In the description of this utility model, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "height", "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 only for the purpose of simplifying the description of this utility model and do not indicate that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. In other words, they should not be construed as limitations on this utility model.
[0044] In this utility model, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating the relative importance of the indicated features or the number of indicated technical features. Therefore, a feature specified as "first" or "second" can explicitly indicate that at least one of those features is included. In the description of this utility model, "multiple" means at least two, such as two, three, etc.; "several" means at least one, such as one, two, three, etc., unless otherwise explicitly specified.
[0045] In this utility model, unless otherwise explicitly defined, the terms "installation," "connection," "linking," "fixing," and "setting," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can also refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0046] In this utility model, unless otherwise explicitly defined, the terms "above," "on top of," "above," "over," "below," "below," "below," or "below" for "first feature above second feature" can refer to direct contact between the first and second features, or indirect contact between the first and second features through an intermediate medium. Furthermore, "above," "above," and "over" for "first feature above second feature" can mean the first feature is directly above or diagonally above the second feature, or simply indicates that the horizontal height of the first feature is higher than the horizontal height of the second feature. Similarly, "below," "below," and "below" for "first feature below second feature" can mean the first feature is directly below or diagonally below the second feature, or simply indicates that the horizontal height of the first feature is lower than the horizontal height of the second feature.
[0047] To fully understand this application, detailed steps and structures will be presented in the following description to illustrate the technical solution of this application. Preferred embodiments of this application are described in detail below; however, in addition to these detailed descriptions, this application may have other implementation methods.
[0048] In the prior art, the first type of carbon fiber composite plate is formed by fixing a carbon fiber plate 1 and a metal plate 2, such as... Figure 5 As shown, the carbon fiber plate 1 has an embedded insert 7 before it is formed. The insert 7 has a threaded hole, and the metal plate 2 has a through hole corresponding to the threaded hole of the insert 7. Then, the carbon fiber plate 1 and the metal plate 2 are fixed together by using screws 5. The carbon fiber composite plate has certain thickness requirements, which need to be sufficient to embed the insert 7 (e.g., a metal nut). This process requires the insert 7 to be pre-installed during carbon fiber forming, which places high demands on operation and precision, resulting in low work efficiency. Moreover, after connecting with screws 5, there are protrusions of a certain height on both the top and bottom surfaces of the plate, making it unsuitable for connecting exterior parts.
[0049] like Figure 6 As shown, the second type of carbon fiber composite plate is formed by fixing a carbon fiber plate 1 and a metal plate 2. Corresponding through holes are opened on the metal plate 2 and the carbon fiber plate 1. Then, the carbon fiber plate 1 and the metal plate 2 are fixed by using bolts 8. This process has high requirements for the accuracy of the opening and assembly, and it also cannot avoid the problem of protrusions on the top and bottom surfaces of the carbon fiber composite plate.
[0050] Both types of carbon fiber composite panels require a protective layer 6 to be placed at the screw 5 or bolt 8 installation location to prevent mechanical wear.
[0051] like Figure 7 As shown, the third type of carbon fiber composite board is formed by fixing a carbon fiber plate 1 and a metal plate 2. Corresponding through holes are opened on the metal plate 2 and the carbon fiber plate 1. Then, the carbon fiber plate 1 and the metal plate 2 are fixed by using metal rivets 3, and the riveting is completed by a core-pulling riveting process. This process has high requirements for the accuracy of the opening and assembly, and it also cannot avoid the problem of protrusions on the top and bottom surfaces of the carbon fiber composite board.
[0052] This embodiment provides a carbon fiber composite plate, such as Figure 1 , Figure 2 As shown, it includes: a carbon fiber plate 1, a metal plate 2, and several metal rivets 3.
[0053] A plurality of first pre-drilled holes 11 are formed on the carbon fiber plate 1, and the first pre-drilled holes 11 extend along the thickness direction of the carbon fiber plate 1; the metal plate 2 is located on the first side of the carbon fiber plate 1 and is in contact with the first side of the carbon fiber plate 1; the metal rivet 3 includes a rivet head 31 and a rivet shank 32; the rivet shank 32 is located in the first pre-drilled holes 11, one end of the rivet shank 32 is fixed to the rivet head 31, and the other end is welded to the metal plate 2; the rivet head 31 presses against the second side of the carbon fiber plate 1, which is the opposite side of the first side. Under the pressing force of the rivet head 31, the carbon fiber plate 1 and the metal plate 2 are tightly attached and firmly fixed together.
[0054] The carbon fiber composite plate provided in this application embodiment achieves the fixation of the carbon fiber plate 1 and the metal plate 2 by means of metal rivets 3 passing through the first pre-drilled hole 11 of the carbon fiber plate 1 and welding them together. No pre-embedding or surface treatment is required, resulting in a simple structure. The only tool needed is welding tools, making it easy to produce and assemble in a standard welding workshop. The carbon fiber composite plate surface has rivet heads 31 on only one side, with no protrusions on the other side, making it suitable for use in exterior parts. The process does not rely on holes in the metal plate 2, and there is no need to align the holes during assembly; therefore, the requirements for operation and precision are not high, making it suitable for industrialization.
[0055] This embodiment provides a manufacturing process for a carbon fiber composite plate, including the following steps:
[0056] 1. The first pre-drilled hole 11 is made on the carbon fiber plate 1: The carbon fiber plate 1 is fixed and positioned offline using tooling or a robot gripper. A punching machine is used, with a punch of appropriate diameter. Different punching pressures are set according to the strength and thickness of the carbon fiber plate 1, and the hole is punched from top to bottom. Due to the special properties of carbon fiber material, a bottom support mold is required to prevent the plate from cracking.
[0057] 2. After obtaining the first pre-drilled hole 11, switch the punch to insert the corresponding metal rivet 3 into the first pre-drilled hole 11. For example... Figure 2 As shown, after punching, the head 31 of the metal rivet 3 is close to the upper side of the carbon fiber plate 1, and the lower end of the metal rivet 3 protrudes slightly. Then the carbon fiber plate 1 is transported to the welding station to contact the metal plate 2.
[0058] 3. For example Figure 3 As shown, welding is performed using electric welding equipment. The upper electrode 100 of the welding gun is placed against the metal rivet 3 on the upper side of the carbon fiber composite plate. The lower electrode 200 of the welding gun is set on the lower side of the carbon fiber composite plate along the thickness direction. After energizing, the lower end of the metal rivet 3 melts under the action of the current to form a weld nugget 33, and the metal rivet 3 is welded to the metal plate 2 as a whole. Under the pressure of the rivet head 31, the carbon fiber plate 1 and the metal plate 2 are fixed to form a carbon fiber composite plate.
[0059] Understandably, depending on the specific product requirements for the carbon fiber composite panel, the number, spacing, diameter, and depth of the first pre-drilled holes 11 on the carbon fiber panel 1 can be adjusted and adapted during the process. The dimensions of the corresponding metal rivets 3 can also be adjusted arbitrarily.
[0060] In an alternative embodiment, such as Figure 1 As shown, the carbon fiber composite plate also includes a gasket 4, which has a second pre-drilled hole 41. The gasket 4 is fitted onto the rivet 32 and located between the rivet head 31 and the carbon fiber plate 1. In this embodiment, the gasket 4 isolates the metal rivet head 31 and the carbon fiber plate 1, thus preventing corrosion. The principle is that different materials have a potential difference, especially between carbon fiber and metal plates. Taking aluminum plates as an example, if aluminum and carbon fiber are in direct contact, corrosion is easily caused, leading to stress relief and plate damage. To eliminate the electrochemical corrosion caused by the potential difference between carbon fiber and aluminum plates, the carbon fiber composite plate in this embodiment has a gasket 4 under the rivet head 31 of the aluminum rivet, preventing direct contact between the aluminum rivet and the carbon fiber plate 1, thereby preventing electrochemical corrosion between the rivet head 31 and the carbon fiber plate 1.
[0061] In an optional embodiment, the gasket 4 is a fiberglass gasket. Fiberglass has excellent insulating properties against carbon fiber and metal, and also has excellent corrosion resistance, enabling long-term isolation between the nail head 31 and the carbon fiber plate 1.
[0062] In an alternative embodiment, such as Figure 4As shown, the nail shank 32 includes a nail shank body 321 and a recessed section 322. The recessed section 322 is located at the end of the nail shank body 321 near the nail head 31. The maximum diameter of the recessed section 322 is equal to the diameter of the nail shank body 321, and the minimum diameter of the recessed section 322 is smaller than the diameter of the nail shank body 321. A gasket 4 is fitted onto the recessed section 322, and the inner diameter of the second pre-drilled hole 41 matches the diameter of the recessed section 322. In this embodiment, the recessed section 322 of the nail shank 32 is designed to be concave, which facilitates the placement of the gasket 4 in the concave position. It is understood that the inner diameter of the second pre-drilled hole 41 needs to match the diameter of the recessed section 322 to facilitate the installation of the gasket 4. Therefore, the inner diameter of the second pre-drilled hole 41 needs to be sufficient for the nail shank body 321 to pass through, while also ensuring that the gasket 4, once located in the recessed section 322, is difficult to slip from the recessed section 322 onto the nail shank body 321.
[0063] This embodiment provides a reference design for the inner diameter of the second pre-drilled hole 41: the second pre-drilled hole 41 and the recessed section 322 are fitted with a tolerance of 0.05mm upper deviation and 0mm lower deviation. Under this size design, the inner diameter of the second pre-drilled hole 41 matches the diameter of the recessed section 322. The metal rivet 3 is shipped with the washer 4 pre-fitted. Due to this size design, the washer 4 is not easy to fall off the rivet shank 32. The metal rivet 3 and the washer 4 are used as a whole, which is convenient.
[0064] In an optional embodiment, the total thickness of the nail head 31 and the shim 4 is less than 1 mm. For example, the thickness of the shim 4 is less than 0.2 mm, and the thickness of the nail head 31 is less than 0.8 mm. With this size design, the thickness of the nail head 31 is sufficient to provide the compressive force for fixing the carbon fiber plate 1, while the height of the nail head 31 protruding from the surface of the carbon fiber plate 1 is within a small range, which allows for a wide range of applications, especially in the use of some appearance parts, where it can significantly reduce the impact of the protruding part on the appearance.
[0065] In an optional embodiment, the first pre-drilled hole 11 is interference-fitted with the rivet 32. In this embodiment, by designing the inner diameter of the first pre-drilled hole 11 to be slightly smaller than the diameter of the rivet 32, a large frictional force can be maintained between the metal rivet 3 and the carbon fiber plate 1 after it is inserted into the first pre-drilled hole 11. This makes it less likely for the metal rivet 3 to fall off during transportation, which helps to reduce the difficulty of component assembly or transportation.
[0066] In an optional embodiment, the diameter of the nail head 31 is 16mm to 20mm. Within this size range, the diameter of the nail head 31 is within the range of electrode cap sizes of conventional welding torches, resulting in high welding feasibility.
[0067] In an optional embodiment, the carbon fiber composite plate of this embodiment has the surface of the rivet head 31 of the rivet 3 treated with anti-corrosion to meet the requirements of the 720h salt spray test. The bottom of the metal rivet 3 is tapered to ensure more stable contact with the metal plate 2 before the welding process, thereby improving the success rate and welding completion of the electric welding process.
[0068] In an optional embodiment, the metal rivet 3 and the metal plate 2 are made of the same material. In this embodiment, the material of the metal rivet 3 is selected based on the material of the metal plate 2, so that the metal rivet 3 can fuse better with the metal plate 2 after melting during the welding process, resulting in a better welding effect. For example, when the metal plate 2 is an aluminum plate, the metal rivet 3 can be an aluminum rivet; when the metal plate 2 is a steel plate, the metal rivet 3 can be a steel rivet. The metal rivet 3 can be formed using a mold, with the mold designed according to the thickness of the carbon fiber plate 1.
[0069] The carbon fiber composite plate provided in this embodiment can be applied to vehicle body parts, such as aluminum or steel bodies, and can be used for connecting exterior parts, expanding the application range of carbon fiber and greatly reducing the limitations of carbon fiber application in aluminum and steel bodies, thus optimizing the complexity of structural design. The welding equipment uses a standard welding torch, unlike traditional cold connections (threaded connections or blind riveting), eliminating the need for production line modifications or new equipment. Existing production line welding torches can be used, and welding stations can be planned according to the process hierarchy. Based on computer-aided engineering (CAE) and vehicle body structural design requirements, metal rivets 3 of different diameters can be designed to ensure the connection strength between the carbon fiber plate 1 and the metal plate 2. Because of the minimal restrictions on structural design, this process can be used in more locations, reducing production costs.
[0070] It should be understood that the above embodiments are exemplary and are not intended to encompass all possible implementations included in the claims. Various modifications and changes can be made to the above embodiments without departing from the scope of this disclosure. Similarly, the various technical features of the above embodiments can be arbitrarily combined to form other embodiments of this application that may not be explicitly described. Therefore, the above embodiments only illustrate several implementations of this application and do not limit the scope of protection of this patent application.
Claims
1. A carbon fiber composite plate, characterized in that, include: A carbon fiber plate having a plurality of first pre-formed holes extending along the thickness direction of the carbon fiber plate. A metal plate, the metal plate being located on the first side of the carbon fiber plate and being in contact with the first side of the carbon fiber plate; A plurality of metal rivets, each rivet comprising a head and a shank; the shank is located within a first pre-drilled hole, one end of the shank is fixed to the head, and the other end is welded to the metal plate; the head presses against a second side of the carbon fiber plate, the second side being the opposite side to the first side.
2. The carbon fiber composite plate according to claim 1, characterized in that, The carbon fiber composite plate also includes a gasket with a second pre-drilled hole. The gasket is fitted onto the nail rod and is located between the nail head and the carbon fiber plate.
3. The carbon fiber composite plate according to claim 2, characterized in that, The gasket is a fiberglass gasket.
4. The carbon fiber composite plate according to claim 2, characterized in that, The nail bar includes a nail bar body and a recessed section. The recessed section is located at the end of the nail bar body near the nail head. The maximum diameter of the recessed section is equal to the diameter of the nail bar body, and the minimum diameter of the recessed section is smaller than the diameter of the nail bar body. The gasket is fitted onto the recessed section, and the inner diameter of the second pre-drilled hole matches the diameter of the recessed section.
5. The carbon fiber composite plate according to any one of claims 2-4, characterized in that, The total thickness of the nail head and the washer is less than 1 mm.
6. The carbon fiber composite plate according to claim 5, characterized in that, The thickness of the gasket is less than 0.2 mm.
7. The carbon fiber composite plate according to claim 5, characterized in that, The thickness of the nail head is less than 0.8 mm.
8. The carbon fiber composite plate according to any one of claims 1-4, characterized in that, The first pre-drilled hole is interference-fitted with the nail rod.
9. The carbon fiber composite plate according to any one of claims 1-4, characterized in that, The diameter of the nail head is 16mm~20mm.
10. The carbon fiber composite plate according to any one of claims 1-4, characterized in that, The metal rivets and the metal plate are made of the same material.