High-toughness aramid paper honeycomb composite multi-layer board

Abstract

The utility model relates to aramid honeycomb board technical field, aims at providing a kind of high-tough aramid paper honeycomb composite multilayer board, by skin layer component-sensing interface layer-core layer-sensing interface layer-skin layer component in turn constitute, core layer, by aramid paper honeycomb constitutes, aramid paper honeycomb's honeycomb hole is filled with STF infiltration foam, the beneficial effects of the utility model are that STF as a kind of non-newtonian fluid, under low strain rate (such as vibration), it shows as soft liquid, can jointly act with foam matrix, provide excellent vibration damping performance;But under high strain rate (such as impact), STF will be instantaneous "hard", viscosity sharply increases, so that the impact resistance and puncture resistance of entire honeycomb core are greatly improved;Further provide a variety of protection capabilities, improve the toughness of the composite multilayer board.

Description

Technical Field

[0001] This utility model relates to the field of aramid honeycomb board technology, and more specifically, to a high-toughness aramid paper honeycomb composite multilayer board. Background Technology

[0002] Aramid paper honeycomb sandwich composite panels, as a typical sandwich structure, are widely used in aerospace, high-speed trains, new energy vehicles, unmanned aerial vehicles, and light ships—fields with stringent requirements for lightweighting and high performance—due to their extremely high specific strength, specific stiffness, lightweight nature, and excellent thermal and sound insulation properties. Their structure typically consists of two layers of high-strength skins (such as glass fiber, carbon fiber, or aramid fiber reinforced resin) bonded together with a lightweight aramid paper honeycomb core material.

[0003] However, existing aramid paper honeycomb composite panels still face several key technical bottlenecks in practical applications: 1. The Inherent Contradiction Between Impact Resistance and Damage Tolerance: Although the aramid fiber skin itself possesses a certain degree of toughness, the entire sandwich structure is highly sensitive to localized impacts, especially those from low-velocity hard objects (such as dropped maintenance tools or runway debris). Such impacts can easily lead to skin dents, core material crushing, and delamination at the skin-core interface. These damages, particularly internal delamination, are difficult to detect visually from the outside, forming hidden structural defects that pose a significant threat to structural safety. Existing technologies typically employ thickening the skin or using high-toughness adhesive films to improve impact resistance, but this often comes at the cost of sacrificing lightweight advantages or increasing additional costs and process complexity, with limited improvement.

[0004] 2. Passive and singular protective performance: Traditional honeycomb panels are purely passive load-bearing structures. Their mechanical properties are fixed once designed and manufactured, making them unable to adapt to the changing external environment during service. For example, they cannot simultaneously and efficiently cope with two completely different mechanical threats: high-frequency vibration (requiring damping energy dissipation) and high-speed impact (requiring instantaneous stiffness). Existing technologies that reinforce the honeycomb core with foam filling can improve crush resistance to some extent, but significantly increase structural weight and offer little improvement in vibration absorption capacity, failing to achieve adaptive protection.

[0005] Therefore, there is an urgent need in this field to develop a new type of composite honeycomb panel. Utility Model Content

[0006] In view of the problems existing in the prior art, this utility model provides a high-toughness aramid paper honeycomb composite multilayer board to solve the technical problems mentioned in the background art.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a high-toughness aramid paper honeycomb composite multilayer board, comprising: The core layer is composed of aramid paper honeycomb, with STF-impregnated foam filling the honeycomb pores. Two sensing interface layers, located on either side of the core layer, are composed of a graphene / TPU piezoresistive composite film. Two skin layer assemblies are located outside the two sensing interface layers, including a first skin layer located on the inner side and a second skin layer located on the outer side. The first skin layer is composed of aramid fiber / epoxy resin prepreg, and the second skin layer is composed of S-glass fiber / epoxy resin prepreg.

[0008] By adopting the above technical solution, STF, as a non-Newtonian fluid, behaves as a soft liquid at low strain rates (such as vibration), and can work together with the foam matrix to provide excellent vibration damping performance; however, at high strain rates (such as impact), STF will instantly "harden" and its viscosity will increase sharply, which will greatly improve the impact resistance and puncture resistance of the entire honeycomb core; thus providing multiple protective capabilities and improving the toughness of the composite multilayer board.

[0009] The present invention is further configured such that the two skin layer components, the two sensing interface layers and the core layer have a connection structure for connection.

[0010] The present invention is further configured such that the connecting structure includes a plurality of through holes and resin pins that are opened through the honeycomb wall of the sensing interface layer and the core layer. The plurality of through holes are opened through the direction perpendicular to the plate surface, and the resin pins pass through the through holes for connecting the two skin layer components.

[0011] The present invention is further configured such that the resin pin is formed by curing liquid epoxy resin in the skin layer assembly.

[0012] The present invention is further configured such that the sensing interface layer also includes electrode terminals located at the edge, for detecting the resistance change of the graphene / TPU piezoresistive composite film by applying current, thereby sensing whether the composite multilayer board is subjected to stress or deformation.

[0013] Compared with the prior art, this utility model provides a high-toughness aramid paper honeycomb composite multilayer board, which has the following beneficial effects: 1. As a non-Newtonian fluid, STF behaves as a soft liquid at low strain rates (such as vibration), and can work together with the foam matrix to provide excellent vibration damping performance. However, at high strain rates (such as impact), STF will "harden" instantly, and its viscosity will increase sharply, which will greatly improve the impact resistance and puncture resistance of the entire honeycomb core. This will provide a variety of protective capabilities and improve the toughness of the composite multilayer board.

[0014] 2. Resin pins connect the two skin layer components and penetrate the through holes opened in the honeycomb wall. The resin pins provide strong mechanical locking force in the Z direction (perpendicular to the board surface), which greatly improves the peel strength and shear strength.

[0015] 3. The sensing interface layer uses a graphene / TPU piezoresistive composite film. By constructing a conductive graphene network within the TPU, this interface layer not only retains its original toughening function but also acquires a piezoresistive effect. When the substrate is subjected to stress or deformation, the spacing between the graphene networks changes, resulting in a measurable change in the film's resistance. By pre-embedding electrode terminals at the edges of the substrate, the entire interface layer becomes a large, distributed strain / damage sensor. Simultaneously, the conductive network also provides excellent electromagnetic shielding and electrostatic dissipation capabilities. Attached Figure Description

[0016] Figure 1 A schematic diagram of the overall structure of a high-toughness aramid paper honeycomb composite multilayer board; Figure 2 This is a schematic diagram of the core layer structure; Figure 3 This is a schematic diagram of the connection structure.

[0017] In the diagram: 1. Core layer; 2. Sensing interface layer; 201. Electrode terminal; 3. Skin layer assembly; 301. First skin layer; 302. Second skin layer; 4. Connection structure; 401. Through hole; 402. Resin pin. Detailed Implementation

[0018] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0019] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0020] In this invention, unless otherwise explicitly 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 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 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.

[0021] In this utility model, unless otherwise stated, the orientations used, such as "up" and "down", usually refer to the direction shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" usually refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not used to limit this utility model.

[0022] like Figure 1 As shown, the high-toughness aramid paper honeycomb composite multilayer board consists of, from top to bottom, a skin layer assembly 3, a sensing interface layer 2, a core layer 1, a sensing interface layer 2, and a skin layer assembly 3. The core layer 1 is composed of aramid paper honeycomb, and the honeycomb cells of the aramid paper honeycomb are filled with STF-impregnated foam.

[0023] Specifically, as a non-Newtonian fluid, STF behaves as a soft liquid under low strain rates such as vibration, and can work together with the foam matrix to provide excellent vibration damping performance; however, under high strain rates such as impact, STF will instantly "harden" and its viscosity will increase sharply, which will greatly improve the impact resistance and puncture resistance of the entire honeycomb core; thus providing a variety of protective capabilities and improving the toughness of the composite multilayer board.

[0024] like Figure 1 As shown, the sensing interface layer 2 is composed of a graphene / TPU piezoresistive composite film. Electrode terminals 201 are also installed on the edge of the sensing interface layer 2 for detecting the resistance change of the graphene / TPU piezoresistive composite film when energized, thereby sensing whether the composite multilayer board is subjected to stress or deformation.

[0025] like Figure 1 As shown, the skin layer assembly 3 includes a first skin layer 301 located on the inner side and a second skin layer 302 located on the outer side. The first skin layer 301 is made of aramid fiber / epoxy resin prepreg, and the second skin layer 302 is made of S-glass fiber / epoxy resin prepreg.

[0026] like Figure 3 As shown, there is a connection structure 4 between the two skin layer assemblies 3, the two sensing interface layers 2 and the core layer 1 for connection. The connection structure 4 includes a plurality of through holes 401 that are opened through the honeycomb wall of the sensing interface layer 2 and the core layer 1 and resin pins 402. The plurality of through holes 401 are opened through the direction perpendicular to the plate surface, and the resin pins 402 pass through the through holes 401 for connecting the two skin layer assemblies 3.

[0027] Among them, the resin pin 402 is formed by curing liquid epoxy resin in the skin layer component 3.

[0028] Specifically, during the co-curing stage of the skin layer assembly 3-sensing interface layer 2-core layer 1-sensing interface layer 2-skin layer assembly 3, driven by vacuum and hot pressing, the liquid epoxy resin of the skin layer passes through these micropores and cures on the other side of the honeycomb wall, forming countless tiny "resin pins 402". These pins provide strong mechanical locking force in the Z direction perpendicular to the board surface, greatly improving the peel strength and shear strength of the interface.

[0029] In all the solutions mentioned above, although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A high-toughness aramid paper honeycomb composite multilayer board, characterized in that it comprises: The core layer (1) is composed of aramid paper honeycomb, and the honeycomb pores of the aramid paper honeycomb are filled with STF-impregnated foam. Two sensing interface layers (2) are located on both sides of the core layer (1) and are composed of graphene / TPU piezoresistive composite films. Two skin layer assemblies (3) are located outside the two sensing interface layers (2), including a first skin layer (301) located on the inner side and a second skin layer (302) located on the outer side. The first skin layer (301) is made of aramid fiber / epoxy resin prepreg, and the second skin layer (302) is made of S-glass fiber / epoxy resin prepreg.

2. The high-toughness aramid paper honeycomb composite multilayer board according to claim 1, characterized in that, The two skin layer components (3), the two sensing interface layers (2), and the core layer (1) have a connection structure (4) for connection.

3. The high-toughness aramid paper honeycomb composite multilayer board according to claim 2, characterized in that, The connection structure (4) includes several through holes (401) and resin pins (402) that are opened through the honeycomb wall of the sensing interface layer (2) and the core layer (1). The several through holes (401) are opened through the direction perpendicular to the plate surface, and the resin pins (402) pass through the through holes (401) to connect the two skin layer components (3).

4. The high-toughness aramid paper honeycomb composite multilayer board according to claim 3, characterized in that, The resin pin (402) is formed by curing liquid epoxy resin in the skin layer assembly (3).

5. The high-toughness aramid paper honeycomb composite multilayer board according to claim 1, characterized in that, The sensing interface layer (2) also includes an electrode terminal (201) located at the edge for detecting the resistance change of the graphene / TPU piezoresistive composite film when energized.

Images