Bionic bolt and inorganic adhesive film synergistic structure, connecting method and application
By machining micron-level grooves on the bolt thread surface and combining them with a staged curing process of nano-reinforced inorganic adhesive film, the problem of insufficient strength of traditional connection technology in extreme environments is solved, achieving a connection effect with high strength, high temperature resistance and long life, which is suitable for the connection of skin and honeycomb core of hypersonic aircraft.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-31
- Publication Date
- 2026-03-31
Smart Images
Figure CN121759093A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of composite material joining technology, and in particular to a biomimetic bolt and inorganic adhesive film synergistic structure, joining method and application. Background Technology
[0002] In the manufacturing of high-end equipment such as aerospace, lightweighting and high reliability are perpetual design pursuits. Traditional joining technologies are mainly divided into two categories: mechanical joining and adhesive bonding. Mechanical joining has advantages such as high strength, good reliability, and detachability, but it also suffers from problems such as stress concentration, significant weight increase, and poor sealing, and is prone to fatigue failure under high-frequency vibration or thermal cycling environments. Adhesive bonding technology can achieve lightweighting, uniform stress distribution, and good sealing and vibration damping performance, but traditional organic adhesives have limited high-temperature resistance (usually with long-term operating temperatures below 300℃), and the adhesive interface is prone to damp heat aging, posing a challenge to long-term reliability.
[0003] For next-generation equipment such as hypersonic vehicles and reusable spacecraft, the connection points between their skin and internal honeycomb core or truss structure need to withstand extreme aerodynamic heating (local temperatures may exceed 800°C), severe thermal shock cycles, and complex aerodynamic loads and vibration environments. Traditional mechanical connections or organic adhesive bonding solutions are difficult to simultaneously meet the extreme requirements of "high strength, resistance to ultra-high temperatures, lightweight, and long lifespan".
[0004] Although there has been research on biomimetic threads or nano-reinforced adhesives, most of it focuses on improvements in a single aspect (biomimetic threads or nano-reinforced adhesives), lacking systematic collaborative innovation. Summary of the Invention
[0005] The purpose of this invention is to provide a biomimetic bolt and inorganic adhesive film synergistic structure, connection method and application. Through systematic synergistic innovation of biomimetic thread microstructure design, nano-reinforced multifunctional inorganic adhesive film and staged precision curing process, the pull-out strength, high temperature resistance, thermal shock resistance and fatigue resistance of the connection structure are significantly improved.
[0006] To achieve the above objectives, the present invention provides a connection method for a biomimetic bolt and an inorganic adhesive film synergistic structure, comprising the following steps: S1. Micron-level grooves are machined on the bolt thread surface to construct a biomimetic thread structure surface; S2. The matrix resin and the nanofiller modified with silane coupling agent are mixed at a mass ratio of 19:0.5, and then dispersed in a solvent. After uniform dispersion, the mixture is rotary evaporated and coated to obtain an inorganic film with a thickness of 0.25 mm. S3. The inorganic adhesive film is coated on the surface of the biomimetic thread structure and then cured by ultraviolet light and heat in sequence to obtain a biomimetic bolt and inorganic adhesive film synergistic structure.
[0007] Preferably, the depth of the micron-sized trench is 50μm-200μm, and the width matches the pitch of the bolt thread. The micron-sized trench is used to increase the contact area with the adhesive film and to create a mechanical interlocking structure.
[0008] Preferably, the micron-level grooves are distributed along the thread axis, and the cross-sectional shape is one of trapezoidal, arc-shaped, and sawtooth-shaped. Pull-out resistance is enhanced by increasing the contact area of the inorganic adhesive film (more than 30% higher than the contact area of traditional structures) and the mechanical interlocking effect (friction coefficient μ≥0.35).
[0009] Preferably, the matrix resin is one of a polycarbosilane precursor, an epoxy resin, and a silicon boron carbon nitride precursor; the nanofiller includes a first-class filler and a second-class filler; the first-class filler is one of aluminum nitride and silicon carbide, with a mass fraction of 3%-10% of the matrix resin mass; the second-class filler is one of reduced graphene oxide and carbon nanotubes, with a mass fraction of 3%-10% of the matrix resin mass; the solvent is one of N,N-dimethylformamide (DMF) and acetone. This invention uses a high-temperature resistant and high-strength material as a base, which, combined with functional nanoparticles, creates a synergistic effect, significantly improving interfacial toughness.
[0010] Preferably, the silane coupling agent is one of KH550, KH560, KH570, KH580, and KH590; the mass ratio of the nanofiller to the silane coupling agent is 1:0.1-0.3. After modification with the silane coupling agent, the nanofiller makes it easier for the inorganic adhesive film to connect with the bolt, thereby producing a high-strength pull-out bolt.
[0011] Preferably, the wavelength of the ultraviolet curing is 360nm-400nm, and the power density is 10mW / cm². 2 -100mW / cm 2 .
[0012] Preferably, under a pressure of 1MPa-5MPa, the temperature is first raised to 60℃-80℃ at a heating rate of 2℃ / min-5℃ / min and held for 20min-40min, then raised to 120℃-160℃ at a heating rate of 2℃ / min-5℃ / min and held for 40min-80min, and finally raised to 180℃-220℃ at a heating rate of 1℃ / min-3℃ / min and held for 60min-120min.
[0013] Preferably, the thickness of the reduced graphene oxide sheets is 0.8 nm to 1.2 nm.
[0014] This invention provides a biomimetic bolt and inorganic adhesive film synergistic structure, which is formed by the connection method of the above-mentioned biomimetic bolt and inorganic adhesive film synergistic structure.
[0015] This invention also provides an application of a biomimetic bolt and inorganic adhesive film synergistic structure in the connection between the skin and honeycomb core of hypersonic aircraft in the aerospace field.
[0016] In summary, the biomimetic bolt and inorganic adhesive film synergistic structure, connection method, and application provided by this invention offer the following advantages compared to traditional technologies: (1) The present invention uses a thread design that mimics the rough bark of plants to process micron-level grooves on the surface of bolt threads, which increases the contact area of the inorganic adhesive film and forms a mechanical interlock, significantly improving the pull-out strength. This results in a substantial increase in both the initial pull-out force and the pull-out force after thermal shock, effectively solving the problem of insufficient pull-out strength in traditional connection methods.
[0017] (2) The inorganic adhesive film prepared by the present invention has added functional nanoparticles, which optimizes the thermal conductivity of the inorganic adhesive film and has a synergistic effect with the matrix resin, significantly improving the interfacial toughness.
[0018] (3) The curing process in this invention innovatively integrates ultraviolet curing and thermal curing technologies and is implemented in stages. In the initial stage, ultraviolet curing is used to promote the rapid formation of a pre-crosslinked network structure in the adhesive film, thereby achieving high-precision positioning of the bolt. In the subsequent stage, thermal curing is used to promote deep crosslinking of the adhesive film, improve the molecular chain structure, and thus enhance the overall strength and durability of the connection part.
[0019] (4) Through multi-scale design of biomimetic structure, nanocomposite and process synergy, the present invention achieves a balance of connection structure strength, heat resistance, precision, lightweight and reliability, and provides a systematic solution to the connection problem in extreme environments such as hypersonic aircraft.
[0020] The technical method of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description
[0021] Figure 1 This is a schematic diagram of the trapezoidal micron-level groove and biomimetic thread structure surface in Embodiment 1 of the present invention; Figure 1 (a) is a schematic diagram of a trapezoidal micron-sized trench; Figure 1 (b) is a schematic diagram of the surface of the biomimetic thread structure; Figure 2 This is a schematic diagram of ultraviolet curing in Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the coating process of inorganic adhesive film on the surface of biomimetic thread structure in Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the connection between the bionic bolt and inorganic adhesive film synergistic structure and the honeycomb core in Embodiment 1 of the present invention; Figure 5This is a comparison chart of the pull-out strength and thermal shock performance of the biomimetic bolt and inorganic adhesive film synergistic structure in Example 1 and the traditional connection structure (traditional mechanical connection or ordinary adhesive bonding structure). Detailed Implementation
[0022] The technical method of the present invention will be further described below with reference to the accompanying drawings and embodiments.
[0023] The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the scope of this application and its application or use.
[0024] In all the examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values.
[0025] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.
[0026] The specific implementation examples are as follows: Example 1 A method for connecting a biomimetic bolt and an inorganic adhesive film synergistic structure includes the following steps: S1, such as Figure 1 As shown, bolts made of graphite / carbon fiber composite material possess excellent high-temperature resistance and mechanical strength. Then, advanced laser micromachining technology is used to machine trapezoidal micron-sized grooves with a depth of 100 μm, a width of 150 μm on one side, and a width of 200 μm on the other side onto the bolt thread surface. Figure 1 As shown in (a), the grooves are evenly distributed along the pitch to construct a biomimetic thread structure surface, as shown in (a). Figure 1 As shown in (b).
[0027] S2. Using a silicon-boron-carbon-nitrogen precursor as the matrix resin, and aluminum nitride (AlN) and reduced graphene oxide (rGO) modified with silane coupling agent KH550 as nanofillers, 10% by mass of surface-modified AlN and 5% by mass of the matrix resin were mixed with the silicon-boron-carbon-nitrogen precursor. Then, acetone was added, and the mixture was first subjected to high-speed shearing to initially disperse the nanomaterials, followed by ultrasonic dispersion to ensure uniform dispersion of AlN and rGO in the resin. Finally, rotary evaporation and coating were performed to obtain an inorganic film with a thickness of 0.25 mm. The mass ratio of nanofillers (AlN and rGO) to silane coupling agent KH550 was 1:0.2.
[0028] S3. Apply the inorganic adhesive film to the surface of the biomimetic thread structure, ensuring complete coverage. Then, at room temperature, such as... Figure 2As shown, a wavelength of 365nm and a power density of 50mW / cm² were used. 2 After irradiating the inorganic adhesive film with ultraviolet light for 8 minutes, it was transferred to a hot press. Under a pressure of 1 MPa, the temperature was first raised to 75°C at a rate of 3°C / min and held for 30 minutes. Then, the temperature was raised to 150°C at a rate of 3°C / min and held for 60 minutes. Finally, the temperature was raised to 180°C at a rate of 3°C / min and held for 40 minutes to obtain a biomimetic bolt and inorganic adhesive film synergistic structure.
[0029] The coating process of inorganic adhesive film onto the surface of biomimetic threaded structures, such as... Figure 3 As shown. Figure 3 The key steps of coating or pre-applying inorganic adhesive film onto the surface of a biomimetic thread structure are demonstrated. The macroscopic shape of the biomimetic bolt and the micron-level trapezoidal groove structure processed on the surface of the biomimetic thread structure are clearly visible in the figure. The inorganic adhesive film is uniformly covered on the surface of the biomimetic thread structure and embedded in the grooves to form a preliminary physical bond and mechanical interlock. Figure 3 This visually demonstrates the core process step of "film pre-positioning" in this invention, which is the basis for subsequent photocuring and thermocuring, and is used to illustrate how to achieve the initial bonding between the film and the complex biomimetic surface.
[0030] A biomimetic bolt and inorganic adhesive film synergistic structure is used for connecting bolts to honeycomb core components, such as... Figure 4 As shown. Figure 4 The demonstration shows the assembly of bionic bolts coated with inorganic adhesive film with a honeycomb core. The honeycomb core material to be connected is prepared first, with pre-drilled holes on its surface. The bionic bolts coated with inorganic adhesive film are screwed into or inserted into the predetermined positions of the honeycomb core. The details of the bolt threads and the honeycomb core hole walls being bonded by the inorganic adhesive film are shown through a magnified partial view. Figure 4 This paper describes the assembly state of the bionic bolt and inorganic adhesive film synergistic structure of the present invention in a practical application scenario (such as the connection between aircraft skin and honeycomb core). It clearly conveys the spatial relationship and connection method among the three components of "bionic bolt-inorganic adhesive film-honeycomb core", demonstrating its engineering practicality as a whole solution.
[0031] When using a biomimetic bolt and inorganic adhesive film synergistic structure for connecting bolts and honeycomb core components, at room temperature, a wavelength of 365nm and a power density of 50mW / cm² are employed. 2After irradiating the inorganic adhesive film with ultraviolet light for 8 minutes, the initial cross-linking of the inorganic adhesive film was induced, and the degree of cross-linking reached about 40%. The bolt position was fixed, and the bolt offset was only 0.08 mm as detected by a laser rangefinder, which effectively ensured the connection accuracy. Then, it was moved to a hot press. Under the pressure of 1 MPa, the temperature was first raised to 75°C at a rate of 3°C / min and held for 30 min. Then, the temperature was raised to 150°C at a rate of 3°C / min and held for 60 min. Finally, the temperature was raised to 180°C at a rate of 3°C / min and held for 40 min, so that the inorganic adhesive film was completely cross-linked. The final degree of cross-linking was 96% as tested by Differential Scanning Calorimetry (DSC). The results of the pull-out strength test showed that the pull-out strength of the bionic bolt and inorganic adhesive film synergistic structure in Example 1 was 40% higher than that of the traditional connection structure. After 100 thermal shock cycles, the pull-out strength retention rate at 200℃ was 92%. At the same time, the thermal conductivity of the inorganic adhesive film reached 8.7W / m·K, which was significantly higher than that of ordinary epoxy resin.
[0032] Example 2 In Example 2, the connection method of the biomimetic bolt and inorganic adhesive film synergistic structure is to replace "processing a trapezoidal micron-level groove with a depth of 100μm, a width of 150μm on one side and a width of 200μm on the bolt thread surface" in step S1 of Example 1 with "processing a trapezoidal micron-level groove with a depth of 50μm, a width of 100μm on one side and a width of 200μm on the other side" in step S1 of Example 1. The remaining steps are the same as in Example 1.
[0033] When using a biomimetic bolt and inorganic adhesive film synergistic structure for connecting bolts and honeycomb core components, at room temperature, a wavelength of 365nm and a power density of 50mW / cm² are employed. 2 After irradiating the inorganic adhesive film with ultraviolet light for 8 minutes, initial cross-linking occurred, with a cross-linking degree of approximately 40%. The bolt position was fixed, and the bolt offset, measured with a laser rangefinder, was only 0.08 mm, effectively ensuring the connection accuracy. The film was then transferred to a hot press. Under a pressure of 1 MPa, the temperature was first raised to 75°C at a rate of 3°C / min and held for 30 minutes. Then, it was raised to 150°C at a rate of 3°C / min and held for 60 minutes. Finally, it was raised to 180°C at a rate of 3°C / min and held for 40 minutes, allowing the inorganic adhesive film to complete cross-linking. The final cross-linking degree, measured by Differential Scanning Calorimetry (DSC), reached 96%. Pull-out strength tests showed that the pull-out strength of the bionic bolt and inorganic adhesive film synergistic structure in Example 1 was 30% higher than that of the traditional connection structure.
[0034] Example 3 In Example 3, the connection method of the biomimetic bolt and inorganic adhesive film synergistic structure is to replace "processing a trapezoidal micron-level groove with a depth of 100μm, a width of 150μm on one side and a width of 200μm on the bolt thread surface" in step S1 of Example 1 with "processing a trapezoidal micron-level groove with a depth of 150μm, a width of 200μm on one side and a width of 200μm on the other side" in step S1 of Example 1. The remaining steps are the same as in Example 1.
[0035] When using a biomimetic bolt and inorganic adhesive film synergistic structure for connecting bolts and honeycomb core components, at room temperature, a wavelength of 365nm and a power density of 50mW / cm² are employed. 2 After irradiating the inorganic adhesive film with ultraviolet light for 8 minutes, initial cross-linking occurred, with a cross-linking degree of approximately 40%. The bolt position was fixed, and the bolt offset, measured with a laser rangefinder, was only 0.08 mm, effectively ensuring the connection accuracy. The film was then transferred to a hot press. Under a pressure of 1 MPa, the temperature was first raised to 75°C at a rate of 3°C / min and held for 30 minutes. Then, the temperature was raised to 150°C at a rate of 3°C / min and held for 60 minutes. Finally, the temperature was raised to 180°C at a rate of 3°C / min and held for 40 minutes, allowing the inorganic adhesive film to complete cross-linking. The final cross-linking degree, measured by Differential Scanning Calorimetry (DSC), reached 96%. Pull-out strength tests showed that the pull-out strength of the bionic bolt and inorganic adhesive film synergistic structure in Example 1 was 42% higher than that of the traditional connection structure.
[0036] Example 4 In Example 4, the connection method of the biomimetic bolt and inorganic adhesive film synergistic structure is to replace "processing a trapezoidal micron-level groove with a depth of 100μm, a width of 150μm on one side and a width of 200μm on the bolt thread surface" in step S1 of Example 1 with "processing a trapezoidal micron-level groove with a depth of 200μm, a width of 250μm on one side and a width of 200μm on the other side" in step S1 of Example 1. The remaining steps are the same as in Example 1.
[0037] When using a biomimetic bolt and inorganic adhesive film synergistic structure for connecting bolts and honeycomb core components, at room temperature, a wavelength of 365nm and a power density of 50mW / cm² are employed. 2After irradiating the inorganic adhesive film with ultraviolet light for 8 minutes, initial cross-linking occurred, with a cross-linking degree of approximately 40%. The bolt position was fixed, and the bolt offset, measured with a laser rangefinder, was only 0.08 mm, effectively ensuring the connection accuracy. The film was then transferred to a hot press. Under a pressure of 1 MPa, the temperature was first raised to 75°C at a rate of 3°C / min and held for 30 minutes. Then, the temperature was raised to 150°C at a rate of 3°C / min and held for 60 minutes. Finally, the temperature was raised to 180°C at a rate of 3°C / min and held for 40 minutes, allowing the inorganic adhesive film to complete cross-linking. The final cross-linking degree, measured by Differential Scanning Calorimetry (DSC), reached 96%. Pull-out strength tests showed that the pull-out strength of the bionic bolt and inorganic adhesive film synergistic structure in Example 1 was 35% higher than that of the traditional connection structure.
[0038] Example 5 In Example 5, the connection method of the bionic bolt and inorganic adhesive film synergistic structure is to replace "transfer to a hot press, and under a pressure of 1 MPa, first raise the temperature to 75°C at a heating rate of 3°C / min, hold for 30 min, then raise the temperature to 150°C at a heating rate of 3°C / min, hold for 60 min, and finally raise the temperature to 180°C at a heating rate of 3°C / min, hold for 40 min" in step S3 of Example 1 with "transfer to a hot press, and hold for 40 min under a pressure of 1 MPa and a heating rate of 180°C". The remaining steps are the same as in Example 1.
[0039] When using a biomimetic bolt and inorganic adhesive film synergistic structure for connecting bolts and honeycomb core components, at room temperature, a wavelength of 365nm and a power density of 50mW / cm² are employed. 2 After irradiating the inorganic adhesive film with ultraviolet light for 8 minutes, initial cross-linking of the inorganic adhesive film was induced, with a cross-linking degree of approximately 40%. The bolt position was fixed, and the bolt offset, measured by a laser rangefinder, was only 0.08 mm, effectively ensuring the connection accuracy. The film was then transferred to a hot press and held at 180℃ and 1 MPa for 40 minutes to achieve complete cross-linking of the inorganic adhesive film. The final cross-linking degree, measured by Differential Scanning Calorimetry (DSC), reached 96%. Pull-out strength tests showed that the pull-out strength of the bionic bolt and inorganic adhesive film synergistic structure in Example 5 was 40% higher than that of the traditional connection structure. After 100 thermal shock cycles, the pull-out strength retention rate was 85%, while the thermal conductivity of the inorganic adhesive film reached 8.5 W / m·K.
[0040] Example 6 In Example 6, a method for connecting a biomimetic bolt and inorganic adhesive film synergistic structure is to adjust the step S2 in Example 1, which involves mixing "10% by mass of surface-modified AlN and 5% by mass of matrix resin with silicon boron carbon nitride precursor", to "3% by mass of surface-modified AlN and 3% by mass of matrix resin with silicon boron carbon nitride precursor". The remaining steps are the same, resulting in a biomimetic bolt and inorganic adhesive film synergistic structure.
[0041] Example 7 In Example 7, the connection method of the biomimetic bolt and inorganic adhesive film synergistic structure is to adjust the step S2 of Example 1, which is "mixing AlN with a surface-modified mass fraction of 10% of the matrix resin and rGO with a mass fraction of 5% of the matrix resin with the silicon boron carbon nitride precursor", to "mixing AlN with a surface-modified mass fraction of 5% of the matrix resin and rGO with a mass fraction of 5% of the matrix resin with the silicon boron carbon nitride precursor". The remaining steps are the same, and the biomimetic bolt and inorganic adhesive film synergistic structure is obtained.
[0042] Example 8 In Example 8, a method for connecting a biomimetic bolt and inorganic adhesive film synergistic structure is to adjust the step S2 in Example 1, which involves mixing "10% by mass of surface-modified AlN and 5% by mass of matrix resin with silicon boron carbon nitride precursor", to "7% by mass of surface-modified AlN and 7% by mass of matrix resin with silicon boron carbon nitride precursor". The remaining steps are the same, resulting in a biomimetic bolt and inorganic adhesive film synergistic structure.
[0043] Comparing Examples 1, 2, 3, and 4, it is evident that the biomimetic bolt and inorganic adhesive film synergistic structure with a micron-level groove depth of 150 μm exhibits the best contact area and mechanical interlocking effect, resulting in the optimal overall performance. Furthermore, fatigue performance testing shows that the biomimetic bolt and inorganic adhesive film synergistic structure with a micron-level groove depth of 150 μm has the longest fatigue life, reaching 10... 6 After several cycles, the fatigue life of the biomimetic bolt and inorganic adhesive film synergistic structure with micron-level trench depths of 50μm and 200μm is approximately 8×10⁻⁶. 5 The sum of 7 × 10 5 Second-rate.
[0044] Comparing the pull-out strength test results of Examples 1 and 5, it can be seen that the pull-out strength retention rate of the bionic bolt and inorganic adhesive film synergistic structure after gradient temperature curing in Example 1 is 92% at 200℃, which is higher than the retention rate of the bionic bolt and inorganic adhesive film synergistic structure directly cured at 180℃ in Example 5. Furthermore, the thermal conductivity of the inorganic adhesive film in the bionic bolt and inorganic adhesive film synergistic structure after gradient temperature curing in Example 1 is also slightly higher than 8.5 W / m·K in Example 5. This indicates that gradient temperature curing helps to improve the thermal stability of the bionic bolt and inorganic adhesive film synergistic structure and the thermal conductivity of the inorganic adhesive film.
[0045] Comparing Examples 6, 7, and 8, it can be seen that when AlN with a surface-modified mass fraction of 5% of the matrix resin and rGO with a mass fraction of 5% of the matrix resin are mixed with silicon boron carbon nitride precursors, the thermal conductivity of the inorganic adhesive film reaches 8.8 W / m·K, the elongation at break reaches 28%, and the pull-out strength of the bionic bolt and inorganic adhesive film synergistic structure is 45% higher than that of the traditional structure. After 50 thermal shock cycles, the pull-out strength can still be maintained at more than 88% of the initial value, indicating that the inorganic adhesive film has the best comprehensive performance under this ratio.
[0046] The temperature distribution of the bionic bolt and inorganic film synergistic structure in Example 1 during thermal shock was monitored in real time using a FLIR A8500sc infrared thermal imaging device. The results showed that when the bionic thread and nano-reinforced inorganic film structure underwent a thermal shock of 800℃, the interface temperature rapidly and uniformly distributed without obvious heat accumulation areas. In contrast, the traditional structure experienced a rapid increase in interface temperature under the same conditions, resulting in localized hot spots. The thermal physical properties of the inorganic film and epoxy resin, such as diffusivity and specific heat capacity, were precisely measured using a Hot Disk TPS2500 transient planar heat source method instrument. The test results showed that the thermal diffusivity of the inorganic film in Example 1 was 0.12 cm⁻¹. 2 With a specific heat capacity of 1.2 J / g·K, it is 60% and 30% higher than that of ordinary epoxy resin, respectively, and has a better thermal management capability.
[0047] Figure 5 The diagram shows a comparison of the pull-out strength and thermal shock performance of the bionic bolt and inorganic adhesive film synergistic structure in Example 1 with traditional connection structures (traditional mechanical connections or ordinary adhesive bonding structures). It intuitively demonstrates the quantitative differences in key mechanical properties between the bionic bolt and inorganic adhesive film synergistic structure of the present invention and traditional bolts in traditional connection structures.
[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical methods of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical methods of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical methods to deviate from the spirit and scope of the technical methods of the present invention.
Claims
1. A method for connecting a biomimetic bolt and an inorganic glue film synergistic structure, characterized in that, It comprises the following steps: S1, processing micron grooves on the bolt thread surface to construct a bionic thread structure surface; S2, mixing the base resin and the nano filler modified by the silane coupling agent, adding a solvent for dispersion treatment, uniformly rotating and evaporating, and coating a film with a thickness of 0.2mm-0.3mm to obtain an inorganic glue film; S3, covering the inorganic glue film on the bionic thread structure surface, and sequentially curing by ultraviolet light and heat to obtain a bionic bolt and inorganic glue film cooperative structure.
2. The method according to claim 1, wherein the method is characterized by, The depth of the micron grooves is 50μm-200μm, and the width matches the pitch of the bolt thread.
3. The method according to claim 1, wherein the method is characterized by: The micron grooves are distributed along the axial direction of the thread, and the cross-sectional shape is one of trapezoidal, arc-shaped and sawtooth-shaped.
4. The method according to claim 1, wherein the method is characterized by, The base resin is one of polycarbosilane precursor, epoxy resin and silicon-boron-carbon-nitrogen precursor; the nano filler comprises a first filler and a second filler; the first filler is one of aluminum nitride and silicon carbide, and the mass fraction is 3%-10% of the mass of the base resin; the second filler is one of reduced graphene oxide and carbon nanotube, and the mass fraction is 3%-10% of the mass of the base resin; and the solvent is one of N,N-dimethylformamide and acetone.
5. The method according to claim 1, wherein the method is characterized by: The silane coupling agent is one of KH550, KH560, KH570, KH580 and KH590; and the mass ratio of the nano filler to the silane coupling agent is 1:0.1-0.
3.
6. The method according to claim 1, wherein the method is characterized by: The wavelength of the ultraviolet light is 360-400 nm, and the power density is 10 mW / cm 2 - 100 mW / cm 2 .
7. The method according to claim 1, wherein the method is characterized by, The heat curing adopts gradient temperature curing, and the specific steps are as follows: under the pressure of 1MPa-5MPa, first, the temperature is raised to 60℃-80℃ at a rate of 2℃ / min-5℃ / min, and then the temperature is raised to 120℃-160℃ at a rate of 2℃ / min-5℃ / min, and finally, the temperature is raised to 180℃-220℃ at a rate of 1℃ / min-3℃ / min, and the temperature is kept for 60min-120min.
8. The method according to claim 4, wherein the method is characterized by, The sheet thickness of the reduced graphene oxide is 0.8nm-1.2nm.
9. A synergistic structure of a biomimetic bolt and inorganic glue film, characterized in that, A bionic bolt and inorganic glue film cooperative structure connected by the connecting method of any one of claims 1-8.
10. A bionic bolt and inorganic glue film cooperative structure in the aerospace field of high-speed aircraft skin and honeycomb core connection according to claim 9.