Composite stiffening plate

Abstract

The utility model relates to a composite reinforcing plate which comprises a base layer substrate, frosted line layers are arranged on the front surface and the back surface of the base layer substrate, and a metal foil layer, a metal alloy buffer layer, a fiber braid layer and an outer protective layer are sequentially stacked on each surface. Groove structures distributed at intervals are machined in the surface of the metal foil layer, and the extending direction of the groove structures and the warp direction of the fiber woven layer intersect at an acute angle. The metal alloy buffer layer is of a sheet structure, and the thickness of the metal alloy buffer layer is larger than that of the metal foil layer and smaller than that of the fiber woven layer. The metal foil layer, the metal alloy buffer layer, the fiber braid layer and the outer protective layer are compounded and fixed through an adhesive layer. The utility model provides a composite stiffening plate which has excellent interlayer binding force, anti-fatigue performance, anti-bending performance and dimensional stability through unique structural design and material selection, and can adapt to different working environments and working condition requirements at the same time.

Description

TECHNICAL FIELD

[0001] The utility model relates to a composite reinforcing plate, especially to a composite reinforcing plate with multiple functional structure layers and capable of significantly improving comprehensive performance, and belongs to the field of circuit board production. BACKGROUND

[0002] In the field of circuit board production, with the continuous development of electronic equipment towards miniaturization and high performance, more stringent requirements are put forward for the performance of reinforcing plates. Nowadays, reinforcing plates not only need to have excellent strength and rigidity to ensure the structural integrity of circuit boards under various complex working conditions, but also need to have excellent fatigue resistance to maintain stability under long-term repeated stress, good bending resistance to adapt to possible bending and folding application scenarios, high dimensional stability to ensure accurate dimensional accuracy under different environmental conditions, and even need to have self-repairing function to effectively prolong the service life and reduce maintenance costs.

[0003] However, traditional reinforcing plates gradually fail to meet these diversified and complex performance requirements in terms of structural design and material selection. For example, some equipment components in high-frequency vibration and dynamic load environments, the existing reinforcing plates are prone to interlayer peeling during long-term operation, resulting in connection failure between structure layers. At the same time, cracks are also prone to continuous expansion, eventually leading to the loss of effectiveness of the entire reinforcing plate structure, seriously affecting the normal operation of the equipment. For components that serve in harsh environments for a long time, due to the lack of effective protection mechanism for traditional reinforcing plates to resist external environmental erosion, combined with the lack of self-repairing ability, once damaged, it is difficult to recover, which greatly shortens the service life of the components and increases the maintenance and replacement cost of the equipment. SUMMARY

[0004] Therefore, the utility model provides a composite reinforcing plate, which has excellent interlayer bonding strength, fatigue resistance, bending resistance and dimensional stability through unique structural design and material selection, and can adapt to different working environments and working conditions.

[0005] The utility model realizes the purpose through the following technical scheme.

[0006] The composite reinforcing plate comprises a base substrate, the front and back surfaces of the base substrate are provided with frosted texture layers, each surface is sequentially stacked with a metal foil layer, a metal alloy buffer layer, a fiber woven layer and an outer protective layer; the surface of the metal foil layer is processed with a groove structure distributed at intervals, the extension direction of the groove structure intersects with the warp direction of the fiber woven layer at an acute angle; the metal alloy buffer layer is a sheet structure, the thickness of which is greater than that of the metal foil layer and less than that of the fiber woven layer; the metal foil layer, the metal alloy buffer layer, the fiber woven layer and the outer protective layer are fixedly combined through an adhesive layer.

[0007] The composite reinforcing plate has excellent interlayer bonding force, fatigue resistance, bending resistance and dimensional stability through unique structural design and material selection, and can adapt to different working environments and working conditions. The space staggered network formed by the acute angle intersecting groove structure and the fiber woven layer significantly enhances the interlayer interface bonding force. The acute angle arrangement of the groove and the warp direction of the fiber woven layer can induce multi-directional stress transmission, disperse the impact load on a single direction, and reduce the risk of interlayer peeling; the thickness gradient design (greater than the metal foil layer and less than the fiber layer) of the metal alloy buffer layer forms a stepped stiffness transition, which can not only absorb high-frequency vibration energy, but also realize rigid support through the fiber layer, so that the overall structure has bending resistance and fatigue resistance; the synergistic effect of the multi-layer heterogeneous materials realizes deformation self-compensation under dynamic load under the premise of light weight, and improves the dimensional stability under complex working conditions.

[0008] Preferably, the frosted texture layer is formed by sandblasting treatment or chemical etching treatment, and the surface roughness Ra value is greater than that of the original surface of the base substrate.

[0009] The frosted texture formed by sandblasting / chemical etching produces a mechanical anchoring effect through the micro concave-convex structure, significantly improving the interfacial bonding strength of the metal foil layer and the substrate. Compared with physical polishing, this process can precisely control the uniformity of the surface roughness, avoiding local stress concentration; the increased specific surface area allows the adhesive to fully infiltrate the substrate surface micropores, forming a three-dimensional interpenetrating structure that effectively inhibits the initiation of interface cracks; at the same time, the rough surface can reflect part of the external load energy, reducing the risk of internal damage of the substrate caused by stress wave propagation, especially suitable for long-term service in high-frequency vibration environments.

[0010] Preferably, the adhesive layer is dispersed with a microcapsule structure, and the shell of the microcapsule structure wraps a liquid adhesive material.

[0011] The microcapsule structure endows the adhesive layer with intelligent self-repairing function: when external force causes microcracks in the adhesive layer, the mechanical energy generated by crack propagation can trigger the rupture of the microcapsule shell, release the liquid adhesive to fill the defect area and solidify, achieving in-situ repair. This design breaks through the limitation of traditional adhesives which fail only once, and is particularly suitable for repeated interface damage scenarios caused by temperature difference alternation or dynamic load; the dispersed microcapsule arrangement strategy avoids the formation of a continuous weak interface, ensuring the overall strength of the adhesive layer while prolonging the service life through local repair; the chemically inert shell of the microcapsule can also block the penetration of external moisture, improving the interlayer corrosion resistance.

[0012] Preferably, the outer protective layer is composed of alternating layers of glass fiber cloth and polyimide film.

[0013] The alternating layers of glass fiber cloth and polyimide film form a multifunctional composite protection system: the high modulus characteristics of glass fiber provide rigid support to resist external scratching and compression deformation; the high temperature resistance of polyimide film (> 300℃) and excellent dielectric strength block the vertical transmission of heat and current, preventing electrochemical corrosion; the alternating arrangement of the two forms a gradient impedance interface that can dissipate impact energy and change the crack propagation path, inhibiting through damage; in addition, the combination of the flexibility of polyimide molecular chains and the rigid skeleton of glass fiber gives the outer protective layer the dual advantages of anti-creep and anti-brittle fracture.

[0014] Preferably, the cross-section of the groove structure is wavy or zigzag continuous concave.

[0015] The wavy / zigzag groove achieves multiple reinforcement through geometric optimization: the complex profile of continuous concave increases the effective contact area by about 30% compared to straight grooves, improving the mechanical interlocking strength with the upper buffer layer; the asymmetric wave peak and valley structure can guide stress waves to reflect and interfere multiple times, weakening the energy transmission efficiency; at the same time, the zigzag groove direction forces the crack propagation path to deflect, requiring more fracture energy to penetrate the interface, significantly delaying the failure process; this design also promotes the capillary penetration effect of the adhesive in the groove, forming a three-dimensional cross-linked solidification network, eliminating the weakly bonded interface area of traditional planar adhesion.

[0016] Preferably, the metal alloy buffer layer is an aluminum-magnesium alloy foil with a thickness of 1.2-1.5 times the thickness of the metal foil layer.

[0017] The aluminum-magnesium alloy buffer layer realizes performance breakthrough through dual design of composition and structure: the addition of magnesium element reduces the density while improving the damping performance of the alloy, which can efficiently absorb impact kinetic energy and convert it into heat energy for dissipation; the optimized grain orientation enables the foil to have anisotropic elastic modulus in the thickness direction, forming a progressive energy buffering mechanism; the matching design with the thickness of the metal foil layer ensures smooth transition of stress from the rigid layer to the flexible layer, avoiding stress concentration caused by sudden change between layers; in addition, the self-passivation property of the aluminum-magnesium alloy can form a dense oxide film on the surface, significantly improving the weather resistance in harsh environments such as humidity and salt spray.

[0018] Preferably, the groove structure is embedded with metal wires or carbon fiber bundles, and the extension direction of the metal wires or carbon fiber bundles is consistent with the direction of the groove structure.

[0019] The embedded metal wires / carbon fiber bundles in the groove form a local reinforcement network: the consistent arrangement with the groove direction enables the reinforcement to extend along the principal stress direction, specifically improving the tensile strength and shear resistance in that direction; the high plasticity of the metal wires can bridge the two sides of the crack and absorb the fracture energy through plastic deformation; the carbon fiber bundles can inhibit elastic deformation in the groove area through high modulus characteristics to prevent excessive stress concentration; the embedding of both can also change the heat conduction / electricity conduction path in the groove area, realizing functional expansion of electromagnetic shielding or thermal management; the matching design of the thermal expansion coefficients of the reinforcement and the matrix further reduces the interfacial thermal stress.

[0020] Preferably, the particle size of the microcapsule structure is smaller than the thickness of the adhesive layer, and is non-uniformly distributed along the cross-section of the adhesive layer.

[0021] The non-uniform distribution strategy of the microcapsules optimizes the repair efficiency through bionics principle: increasing the microcapsule distribution density in the high stress area of the adhesive layer (such as the interlayer edge and the hole periphery) forms a key defense network to ensure that the repair mechanism is triggered as soon as the damage initiates; the design of particle size smaller than the thickness of the adhesive layer avoids the protrusion of the microcapsules affecting the interfacial adhesion, while ensuring that the liquid adhesive can fully fill the cracks of different depths after the shell is broken; the gradient particle size distribution enables small-sized capsules to preferentially repair superficial microcracks, and large-sized capsules to cope with deep penetrating damage, forming a hierarchical response system to maximize the utilization efficiency of repair resources.

[0022] The beneficial effects of the utility model compared with the prior art are:

[0023] This novel composite reinforcing plate, through its unique structural design and material selection, possesses excellent interlayer bonding, fatigue resistance, bending resistance, and dimensional stability, while also adapting to various working environments and conditions. The acute-angled groove structure, forming a spatially interwoven network with the fiber braided layer, significantly enhances the interlayer bonding. The acute-angled arrangement of the warp direction of the fiber braided layer and the grooves induces multi-directional stress transmission, dispersing the concentrated impact load in a single direction and reducing the risk of interlayer delamination. The thickness gradient design of the metal alloy buffer layer (greater than the metal foil layer, less than the fiber layer) creates a stepped stiffness transition, absorbing high-frequency vibration energy while providing rigid support through the fiber layer, giving the overall structure both bending and fatigue resistance. The synergistic effect of multiple heterogeneous materials achieves deformation self-compensation under dynamic loads while maintaining lightweight design, improving dimensional stability under complex working conditions. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a cross-sectional view of a composite reinforcing plate according to an embodiment of the present invention.

[0026] Figure 2 This is a schematic diagram of the adhesive layer structure according to an embodiment of the present invention.

[0027] Figure 3 for Figure 1 A magnified view of region A in the middle.

[0028] Label Explanation

[0029] (1) Base substrate; (2) Frosted texture layer; (3) Metal foil layer; (4) Metal alloy buffer layer; (5) Fiber braided layer; (6) Outer protective layer; (7) Groove structure; (8) Adhesive layer; (9) Microcapsule structure; (10) Glass fiber cloth; (11) Polyimide film; (12) Metal wire. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the application claimed, but merely represents selected embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the application.

[0032] It should be noted that similar reference numbers and letters represent similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. In the description of the embodiments of the application, it should be understood that the terms "upper", "lower", "left", "right", "vertical", "horizontal" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing the application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the application.

[0033] It should be noted that the embodiments in the application and the features in the embodiments can be combined with each other without conflict.

[0034] The technical solutions in the application will be described below with reference to the drawings.

[0035] The embodiment provides a composite reinforcing plate, which comprises a base substrate 1, the front and back surfaces of the base substrate 1 are provided with frosted lines 2, each surface is sequentially stacked with a metal foil layer 3, a metal alloy buffer layer 4, a fiber woven layer 5 and an outer protective layer 6; the surface of the metal foil layer 3 is processed with a groove structure 7 distributed at intervals, the extension direction of the groove structure 7 and the warp direction of the fiber woven layer 5 are crossed at an acute angle; the metal alloy buffer layer 4 is a sheet structure, the thickness of the metal alloy buffer layer 4 is greater than that of the metal foil layer 3 and less than that of the fiber woven layer 5; the metal foil layer 3, the metal alloy buffer layer 4, the fiber woven layer 5 and the outer protective layer 6 are fixedly combined through an adhesive layer 8.

[0036] The space interlaced network is formed by the groove structure 7 intersecting at acute angles with the fiber woven layer 5, which significantly enhances the interlaminar interface bonding force. The acute angle arrangement of the grooves 7 and the warp direction of the fiber woven layer 5 can induce stress multi-directional transmission, disperse the impact load on a single direction, and reduce the risk of interlaminar peeling; the thickness gradient design of the metal alloy buffer layer 4 forms a stepped stiffness transition, which can not only absorb high-frequency vibration energy but also provide rigid support through the fiber layer 5, so that the overall structure has both bending resistance and fatigue resistance; the synergistic effect of the multi-layer heterogeneous materials realizes deformation self-compensation under dynamic load under the premise of lightweight, and improves the dimensional stability under complex working conditions.

[0037] In this embodiment, the frosted texture layer 2 is formed by sandblasting or chemical etching treatment, and the surface roughness Ra value is greater than the original surface of the base substrate 1.

[0038] The frosted texture 2 formed by sandblasting / chemical etching produces a mechanical anchoring effect through the micro concave-convex structure, significantly improving the interfacial bonding strength between the metal foil layer 3 and the substrate 1. Compared with physical polishing, this process can precisely control the uniformity of the surface roughness distribution, avoiding local stress concentration; the increased specific surface area allows the adhesive to fully infiltrate the surface micropores of the substrate 1, forming a three-dimensional interpenetrating structure that effectively inhibits the initiation of interfacial cracks; at the same time, the rough surface can reflect part of the external load energy, reducing the risk of internal damage to the substrate 1 caused by stress wave propagation, especially suitable for long-term service in high-frequency vibration environments.

[0039] In this embodiment, the adhesive layer 8 is dispersed with microcapsule structures 9, and the shell of the microcapsule structure 9 encapsulates a liquid adhesive material.

[0040] The microcapsule structure 9 endows the adhesive layer 8 with intelligent self-repairing function: when external force causes microcracks in the adhesive layer 8, the mechanical energy generated by crack propagation can trigger the rupture of the microcapsule 9 shell, release the liquid adhesive to fill the defect area and solidify, achieving in-situ repair. This design breaks through the limitation of traditional adhesives that fail only once, and is particularly suitable for repeated interface damage scenarios caused by temperature difference alternation or dynamic load; the dispersed microcapsule 9 arrangement strategy avoids the formation of continuous weak interfaces, while ensuring the overall strength of the adhesive layer 8, prolonging the service life through local repair; the chemically inert shell of the microcapsule 9 also blocks the penetration of external moisture, improving the interlayer corrosion resistance. The distribution mode of the microcapsules is gradient distribution or random distribution.

[0041] In this embodiment, the outer protective layer 6 is composed of alternating layers of glass fiber cloth 10 and polyimide film 11.

[0042] The alternating layers of glass fiber cloth 10 and polyimide film 11 form a multifunctional composite protection system: the high modulus characteristics of glass fiber cloth 10 provide rigid support to resist external scratches and compression deformation; the high temperature resistance of polyimide film 11 > 300℃ and excellent dielectric strength block the vertical transmission of heat and current, preventing electrochemical corrosion; the alternating arrangement of the two forms a gradient impedance interface that can dissipate impact energy and change the crack propagation path to inhibit through damage; in addition, the combination of the flexible molecular chain of polyimide 11 and the rigid skeleton of glass fiber 10 gives the outer protective layer 6 the dual advantages of anti-creep and anti-brittle fracture.

[0043] In this embodiment, the cross section of the groove structure 7 is wavy or zigzag continuous concave.

[0044] The wavy / zigzag groove 7 realizes multiple reinforcement through geometric optimization: the complex profile of the continuous concave increases the effective contact area by about 30% compared to straight grooves, improving the mechanical engagement strength with the upper buffer layer; the asymmetric wave peak and valley structure can guide stress waves to reflect and interfere multiple times, weakening the energy transmission efficiency; at the same time, the zigzag groove 7 forces the crack propagation path to deflect, requiring more fracture energy to penetrate the interface and significantly delaying the failure process; this design also promotes the capillary penetration effect of the adhesive in the groove 7, forming a three-dimensional cross-linked solidification network and eliminating the weakly bonded interface area of traditional planar bonding.

[0045] In this embodiment, the metal alloy buffer layer 4 is an aluminum-magnesium alloy foil, which is 1.2-1.5 times the thickness of the metal foil layer 3.

[0046] The aluminum-magnesium alloy buffer layer 4 realizes performance breakthrough through dual design of composition and structure: the addition of magnesium elements reduces density while improving alloy damping performance, which can efficiently absorb impact kinetic energy and convert it into heat energy dissipation; optimized grain orientation makes the foil have anisotropic elastic modulus in the thickness direction, forming a progressive energy buffering mechanism; the matching design with the thickness of the metal foil layer 3 ensures smooth transition of stress from the rigid layer to the flexible layer, avoiding stress concentration caused by sudden changes between layers; in addition, the self-passivation characteristics of aluminum-magnesium alloy 4 can form a dense oxide film on the surface, significantly improving the weather resistance in harsh environments such as humidity and salt spray.

[0047] In this embodiment, a metal wire 12 is embedded in the groove structure 7, and the extension direction of the metal wire 12 is consistent with the direction of the groove structure 7. In other embodiments, carbon fiber bundles can be used instead of metal wires.

[0048] The metal wire 12 / carbon fiber bundle embedded in the groove forms a local reinforcement network: the arrangement consistent with the direction of the groove 7 makes the reinforcement extend along the principal stress direction, and improves the tensile strength and shear resistance in this direction; the high plasticity of the metal wire 12 can bridge the two sides of the crack, and absorb the fracture energy through plastic deformation; the carbon fiber bundle can inhibit the elastic deformation of the groove area through the high modulus characteristics, and prevent excessive stress concentration; the embedding of the two can also change the heat conduction / electricity conduction path of the groove area, realize the functional expansion of electromagnetic shielding or heat management; and the matching design of the thermal expansion coefficient of the reinforcement and the matrix further reduces the interface thermal stress.

[0049] In the embodiment, the particle size of the microcapsule structure 9 is smaller than the thickness of the adhesive layer 8, and is non-uniformly distributed along the cross section of the adhesive layer 8.

[0050] The non-uniform distribution strategy of the microcapsule 9 optimizes the repair efficiency through the principle of bionics: the distribution density of the microcapsule 9 is increased in the high stress area of the adhesive layer 8, such as the interlayer edge and the hole periphery, to form a key defense network, so that the repair mechanism can be triggered as soon as the damage is initiated; the design that the particle size is smaller than the thickness of the adhesive layer 8 avoids the influence of the microcapsule 9 protruding the interface on the interlayer adhesion, while ensuring that the liquid adhesive can fully fill the cracks of different depths after the shell is broken; the gradient distribution of the particle size makes the small-size capsules repair the superficial microcracks preferentially, and the large-size capsules cope with deep penetrating damage, forming a hierarchical response system to maximize the utilization efficiency of repair resources.

[0051] Although the embodiments of the utility model have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to these embodiments without departing from the principles and spirits of the utility model, and the scope of the utility model is defined by the appended claims and their equivalents.

Claims

1. A composite reinforcement sheet comprising a base substrate (1), characterized in that, The base substrate (1) is provided with a frosted pattern layer (2) on its front and back surfaces, and each surface is sequentially stacked with a metal foil layer (3), a metal alloy buffer layer (4), a fiber woven layer (5) and an outer protective layer (6); The metal foil layer (3) is provided with a groove structure (7) distributed at intervals on its surface, and the extension direction of the groove structure (7) is intersected with the warp direction of the fiber woven layer (5) at an acute angle; The metal alloy buffer layer (4) is a sheet structure, and its thickness is greater than that of the metal foil layer (3) and less than that of the fiber woven layer (5); The metal foil layer (3), the metal alloy buffer layer (4), the fiber woven layer (5) and the outer protective layer (6) are fixed by an adhesive layer (8).

2. The composite reinforcement plate according to claim 1, characterized by The frosted pattern layer (2) is formed by sandblasting treatment or chemical etching treatment, and its surface roughness Ra value is greater than that of the original surface of the base substrate (1).

3. The composite reinforcement plate according to claim 1, characterized by The adhesive layer (8) is dispersed with a microcapsule structure (9), and the shell of the microcapsule structure (9) is wrapped with a liquid adhesive material.

4. The composite reinforcement plate according to claim 1, wherein The outer protective layer (6) is composed of glass fiber cloth (10) and polyimide film (11) alternately stacked.

5. The composite reinforcement plate according to claim 1, wherein The cross section of the groove structure (7) is wavy or polyline continuous concave.

6. The composite reinforcement plate according to claim 1, wherein The metal alloy buffer layer (4) is an aluminum magnesium alloy foil.

7. The composite reinforcement plate according to claim 5, wherein The groove structure (7) is embedded with a metal wire (12) or a carbon fiber bundle, and the extension direction of the metal wire (12) or the carbon fiber bundle is consistent with the direction of the groove structure (7).

8. The composite reinforcement plate according to claim 3, wherein The particle size of the microcapsule structure (9) is smaller than the thickness of the adhesive layer (8), and is non-uniformly distributed along the cross section of the adhesive layer (8).

Images