CN118219619A - Insect exoskeleton morphology layering composite material panel, sandwich structure and preparation method - Google Patents

Abstract

The application discloses an insect exoskeleton morphological layering composite material panel, a sandwich structure and a preparation method. The sandwich structure comprises two bionic layering composite material panels and an aramid honeycomb core layer. The bionic layering composite material panel is formed by taking reference to spiral stacking microstructures of insect exoskeletons, layering design considers the symmetry and balance requirements of the composite material, introducing a fixed rotation angle between adjacent fiber layers, circularly paving a plurality of periods by taking 180 degrees as one period, and performing hot pressing and curing. The bionic layering design effectively reduces interlayer shear stress of the composite material, weakens inherent anisotropism of the composite material, and improves transverse bearing and impact resistance. The bionic layering composite material panel and the aramid fiber honeycomb core layer have the advantages of high specific strength, high specific rigidity, impact energy absorption, vibration reduction, noise reduction, electromagnetic shielding and the like, and the structural function integrated material with more excellent comprehensive performance is obtained, so that the bionic layering composite material panel and the aramid fiber honeycomb core layer are expected to be widely applied to main bearing structures of various aerospace craft.

Description

Insect exoskeleton morphology layering composite material panel, sandwich structure and preparation method

Technical Field

The application relates to the technical field of composite material structures in the aerospace field, in particular to an insect exoskeleton morphological layering composite material panel, a sandwich structure and a preparation method.

Background

As the most commonly used structural board of the current spacecraft, the carbon-skin aluminum honeycomb sandwich board cannot meet the development requirement of future lightweight design. The traditional sandwich panel consists of carbon fiber composite material panels and aluminum honeycomb sandwich layers, wherein the layering design of the composite material panels is mainly orthogonal stacking. When the sandwich plate bears external mechanical load, the composite material panel is easy to generate matrix cracking, interlayer layering and other failures, and the aluminum honeycomb core layer also has defects of cell malformation, cell wall non-uniformity and the like, so that the mechanical property of the whole structure is degraded, the strength and the rigidity are reduced, and the impact energy absorption is weakened. In order to meet the development requirement of a spacecraft on a main bearing structure, a multifunctional structural plate which is light in weight, high in strength and meanwhile compatible with the characteristics of impact energy absorption, vibration reduction, noise reduction and electromagnetic shielding is required to be developed.

Disclosure of Invention

The application provides an insect exoskeleton morphological layering composite material panel, a sandwich structure and a preparation method.

In a first aspect, there is provided an insect exoskeleton morphology layered composite panel, the panel being formed from a multi-layer unidirectional fiber prepreg hot-press, the layer-by-layer fiber directions on the panel being arranged in the order [ n x 180 °/n x 180 ° - θ/n x 180 ° -2 θ/…/2 θ/θ/0 ° ] _s if the panel is an even layer composite, and the layer-by-layer fiber directions on the panel being arranged in the order [ (n x 180 °/n x 180 ° - θ/n x 180 ° -2 θ/…/2 θ/θ/0 ° ] _s/0 ° ] if the panel is an odd layer composite.

With reference to the first aspect, in certain implementations of the first aspect, 5 ° +.θ+.ltoreq.30°, and 180 ° is an integer multiple of θ.

With reference to the first aspect, in certain implementations of the first aspect, the fiber is at least one of: carbon fiber, glass fiber, basalt fiber and natural fiber.

In a second aspect, there is provided a method of making an insect exoskeleton morphologically layered composite panel as described in any one of the implementations of the first aspect above, comprising:

Cutting unidirectional fiber prepreg according to the fiber direction of 0 DEG and gradually and linearly increasing deflection theta according to the layering sequence, cutting to obtain 2n+2 prepreg layering if the panel is an even-numbered layer composite material, and cutting to obtain 2n+3 prepreg layering if the panel is an odd-numbered layer composite material;

Stacking the cut prepregs layer by layer according to a layering sequence, performing hot press forming and cooling treatment on the stacked prepregs, wherein the layering sequence is [ n×180 degrees/n×180 degrees-theta/n×180 degrees-2 theta/…/2 theta/0 degrees ] _s for even-layer composite materials; for odd-layer composites, the ply sequence is [ (n x 180/n x 180-theta/n x 180-2 theta/…/2 theta/0 deg.) _s/0 deg. ].

With reference to the second aspect, in certain implementations of the second aspect, the unidirectional fiber prepreg has a mass per unit area of 50 to 250g/m ² and a thickness of 0.05 to 0.25mm.

With reference to the second aspect, in some implementations of the second aspect, the hot pressing treatment is an autoclave molding process, the molding pressure is 0.1-0.8 MPa, the heating rate is 1-5 ℃/min, the molding temperature is 125-150 ℃, and the heat preservation time is 0.5-2 h.

With reference to the second aspect, in certain implementations of the second aspect, the cooling treatment is to reduce the temperature to 80 ℃ at a rate of 2-4 ℃/min, and then cool naturally to room temperature.

In a third aspect, there is provided an insect exoskeleton morphology high strength and toughness composite sandwich structure comprising an upper and a lower two-layer insect exoskeleton morphology layered composite panel as described in any one of the first to second aspects above, and a honeycomb core sandwiched between the two-layer insect exoskeleton morphology layered composite panel.

With reference to the third aspect, in some implementations of the third aspect, the honeycomb core is an aramid honeycomb, the core height T is 5-25 mm, the nominal cell side length a is 3-10 mm, the core thickness N is 0.1-0.5 mm, and the density is 30-160 kg/m ³.

In a fourth aspect, a method for preparing the high-strength and high-toughness composite sandwich structure with the insect exoskeleton morphology according to any one of the implementation manners of the third aspect is provided, where the method includes:

uniformly coating two-component epoxy resin glue on one side of an upper-layer insect exoskeleton-shaped layered composite material panel and a lower-layer insect exoskeleton-shaped layered composite material panel, and adhering the two-component epoxy resin glue on the upper side and the lower side of a honeycomb core body with the same area;

clamping the attached insect exoskeleton form high-strength and high-toughness composite material sandwich structure by using a clamp, curing at normal temperature for 8-10 h, and detaching the clamp to obtain the epoxy resin bonded insect exoskeleton form high-strength and high-toughness composite material sandwich structure.

Compared with the prior art, the scheme provided by the application at least comprises the following beneficial technical effects:

1) And (3) light weight: the composite sandwich structure is used as a main bearing structure, so that the overall weight of the spacecraft can be reduced, and the fuel efficiency and the load capacity of the spacecraft are improved; 2) High stiffness and strength: the composite sandwich structure has excellent rigidity and strength, and can bear the mechanical load faced in the running process of the spacecraft; 3) Fatigue resistance: the composite sandwich structure has excellent fatigue resistance and can prolong the service life of the spacecraft; 4) Impact resistance: the composite material sandwich structure can absorb and disperse impact energy of space debris and improve the protective performance of the spacecraft.

The insect exoskeleton shape high-strength and high-toughness composite material sandwich structure has important application prospect in the aerospace field, and can improve the safety, reliability and performance of a spacecraft. 1) The change of the orientation of the composite material fibers optimizes the overall strength and rigidity of the material; 2) Under the same load working condition, the interlayer stress of the fiber reinforced composite material of the bionic layering is smaller, layering damage is less likely to occur, and the interface performance of the fiber reinforced composite material is improved; 3) Spiral crack propagation can be formed in the bionic spiral structure, and the change of a local fracture mode at the front end of the crack leads to the reduction of the local strain energy release rate, so that the external energy release rate required by crack propagation is increased, and the toughness of the crack is improved.

The innovation points of the application include: 1) The sandwich structure panel of the composite material is designed by the spiral stacked microstructure of the layered fiber layers in the insect exoskeleton shape, so that the interlayer shear stress of the composite material is reduced, the inherent anisotropism of the composite material is weakened, and the mechanical property of the sandwich structure for resisting out-of-plane load is improved; 2) The spiral stacking microstructure of the insect exoskeleton is designed, and meanwhile, symmetry and balance design are combined, so that the molding quality of the composite material is improved, the prepreg is rotationally cut, corner warping and secondary processing of a plate after molding are avoided, and the preparation process flow is simplified; 3) The advantages of high specific strength, high specific rigidity, impact energy absorption, vibration reduction, noise reduction, electromagnetic shielding and the like of the bionic layering composite material panel and the aramid fiber honeycomb core layer are fully utilized, multifunctional coupling is realized, and the structural function integrated material with more excellent comprehensive performance is obtained.

In the aerospace field, weight loss and structural integrity are critical, and the engineering of the present application is of practical value: 1) The high specific strength enables the construction of light and strong components, reduces the overall weight of the spacecraft, and further improves fuel efficiency and payload capacity; 2) Has excellent toughness and damage resistance, can provide better impact resistance and fatigue resistance, ensuring the structural integrity and safety of the aircraft and spacecraft; 3) The sandwich design can effectively absorb energy during high-speed collision, such as the situation encountered during space debris collision or atmospheric reentry, so that the survivability of the spacecraft under extreme conditions is improved; 4) The aramid fiber honeycomb core layer can provide functions of thermal isolation, vibration reduction, noise reduction, electromagnetic shielding and the like, and further improves performance and comfort of the spacecraft. In general, the high-strength and high-toughness bionic composite sandwich structure with the insect exoskeleton shape has important application value in the aerospace field. These structures have the potential to reduce weight, maintain structural integrity, resist impact and absorb energy, and are expected to bring revolutionary changes to the design and performance of the spacecraft, enabling a more efficient, safe and durable spacecraft.

In conclusion, the insect exoskeleton form high-strength and high-toughness composite material sandwich structure and the preparation method thereof have excellent mechanical properties and capabilities, can meet the requirements of engineering fields on high-performance materials, and have wide application prospects.

Drawings

Fig. 1 is a schematic diagram of a sandwich structure of a high-strength and high-toughness composite material in the form of an insect exoskeleton.

The figure indicates: 1-bionic layering composite material panel, 2-aramid honeycomb core.

Fig. 2 is a schematic diagram of an insect exoskeleton morphology composite lay-up in accordance with the present application.

Fig. 3 is a schematic view of prepreg cutting according to the present application.

Fig. 4 is a schematic view of an aramid honeycomb core according to the present application.

The figure indicates: t-core height, a-nominal cell side length, N-core thickness.

Fig. 5 is a schematic diagram of a quasi-static indentation test according to the present application.

Fig. 6 is a quasi-static indentation test force displacement curve of example 1 according to the present application.

Fig. 7 shows the peak load and energy absorption results of example 1 according to the present application.

Fig. 8 is a quasi-static indentation test force displacement curve of example 2 according to the present application.

Fig. 9 shows the peak load and energy absorption results of example 2 according to the present application.

Detailed Description

The application is described in further detail below with reference to the drawings and the specific embodiments.

The application provides an insect exoskeleton morphology layering composite panel. The panel is obtained by hot press molding of a multi-layer unidirectional fiber prepreg, and if the panel is an even-layer composite, the layer-by-layer fiber directions on the panel are arranged in the order [ n×180 °/n×180 ° - θ/n×180 ° -2θ/…/2θ/θ/0 ° ] _s, and if the panel is an odd-layer composite, the layer-by-layer fiber directions on the panel are arranged in the order [ (n×180 °/n×180 ° - θ/n×180 ° -2θ/…/2θ/θ/0 ° ] _s/0 °).

The application also provides a preparation method of the insect exoskeleton morphology layering composite panel, which comprises the following steps.

1) Cutting unidirectional fiber prepreg according to the fiber direction of 0 DEG and gradually and linearly increasing deflection theta according to the layering sequence, cutting to obtain 2n+2 prepreg layering if the panel is an even-numbered layer composite material, and cutting to obtain 2n+3 prepreg layering if the panel is an odd-numbered layer composite material;

2) Stacking the cut prepregs layer by layer according to a layering sequence, performing hot press forming and cooling treatment on the stacked prepregs, wherein the layering sequence is [ n×180 degrees/n×180 degrees-theta/n×180 degrees-2 theta/…/2 theta/0 degrees ] _s for even-layer composite materials; for odd-layer composites, the ply sequence is [ (n x 180/n x 180-theta/n x 180-2 theta/…/2 theta/0 deg.) _s/0 deg. ].

Fig. 1 is a schematic diagram of an insect exoskeleton morphology high-strength and high-toughness composite sandwich structure provided by the application. The sandwich structure can comprise an aramid honeycomb core body 2 and an upper layer of bionic layering composite material panel 1 and a lower layer of bionic layering composite material panel 1, wherein the aramid honeycomb core body 2 is clamped between the upper layer of bionic layering composite material panel 1 and the lower layer of bionic layering composite material panel 1. The biomimetic layered composite panel 1 is an insect exoskeleton morphology layered composite panel as described above.

The application also provides a preparation method of the insect exoskeleton morphological high-strength and toughness composite material sandwich structure, which comprises the following steps.

1) First, a bionic spiral design is performed on the layering sequence of the composite material panels. Determining a spiral period n and a spiral angle theta in consideration of symmetry and balance requirements, wherein for even-numbered composite materials, the layering sequence is [ n×180 °/n×180 ° -theta/n×180 ° -2θ/…/2θ/θ/0 ° ] _s, as shown in fig. 2; for odd-layer composites, the ply sequence is [ (n x 180/n x 180-theta/n x 180-2 theta/…/2 theta/0 deg.) _s/0 deg. ].

The bionic layering design method considers the symmetry requirement, eliminates the in-plane-out-of-plane and out-of-plane-in coupling effect of the composite material laminated plate, and accordingly avoids buckling deformation of the obtained laminated plate.

The bionic layering design method considers the requirement of equilibrium, and eliminates the pull-shear coupling effect of the composite material laminated plate in a unidirectional stretching state.

In some embodiments, the helix angle in the biomimetic layup design method should satisfy 5.ltoreq.θ.ltoreq.30°, with 180 ° being an integer multiple of θ.

2) Next, the unidirectional fiber prepreg was cut in a direction of 0 ° in the fiber direction according to the ply design with gradually increasing linear deflection θ, as shown in fig. 3.

In some embodiments, the unidirectional fiber prepreg is an epoxy resin prepreg of carbon fiber, glass fiber, basalt fiber, natural fiber and the like, and the unit area mass is 50-250 g/m ², and the thickness is 0.05-0.25 mm.

3) And then, stacking the cut prepregs layer by layer according to the step layering design, and carrying out hot press molding and cooling treatment on the stacked prepregs.

In some embodiments, the hot pressing process is an autoclave molding process, the molding pressure is 0.1-0.8 MPa, the heating rate is 1-5 ℃/min, the molding temperature is 125-150 ℃, and the heat preservation time is 0.5-2 h.

In some embodiments, the cooling process is to reduce the temperature to 80 ℃ at a rate of 2-4 ℃/min, followed by natural cooling to room temperature.

4) Finally, the composite material is cut into two panels with the same area, and the two panels are coated with the uniform bi-component epoxy resin adhesive on one side and adhered to the upper side and the lower side of the core body with the same area. The composite core is shown in fig. 4. And clamping the bonded composite honeycomb sandwich plate by using a clamp, curing at normal temperature for 8-10 h, and disassembling the clamp to obtain the epoxy resin bonded full composite sandwich plate.

In some embodiments, the honeycomb core is an aramid honeycomb, the core height T is 5-25 mm, the nominal cell side length a is 3-10 mm, the core thickness N is 0.1-0.5 mm, and the density is 30-160 kg/m ³.

Example 1

1) Firstly, carrying out bionic spiral design on the layering sequence of a composite material panel, determining that the spiral period is 2, the spiral angle is 10 degrees, the layer number is odd, the layering sequence is [ (360 degrees/350 degrees/340 degrees/…/20 degrees/10 degrees/0 degrees ] _s/0 degrees ], and then carrying out cutting on unidirectional carbon fiber prepreg with the fiber direction being 0 degrees according to the layering design in a successive deflection way of 10 degrees;

2) Then, stacking the cut carbon fiber prepregs layer by layer according to the step layering design, performing hot press molding on the stacked prepregs, wherein the molding pressure is 0.1MPa, the heating rate is 4 ℃/min, the molding temperature is 130 ℃, the heat preservation time is 60min, then reducing the temperature to 90 ℃ at the rate of 4 ℃/min, and naturally cooling to room temperature;

3) Finally, cutting the composite material into two panels with the same area, coating the single face with uniform bi-component epoxy resin glue, taking an aramid fiber honeycomb core body, wherein the nominal cell side length is 3.2mm, the height is 10mm, the density is 48kg/m ³, adhering the panels on the upper side and the lower side of the composite material core body with the same area, clamping the adhered composite material honeycomb sandwich plate by using a clamp, curing for 9 hours at normal temperature, and detaching the clamp to obtain the epoxy resin glued full composite material sandwich plate.

The press-fit test was performed on the prepared biomimetic layered composite material sandwich structure according to ASTM D6264 standard, as shown in fig. 5, using a hemispherical press head with a diameter of 10mm and a pressing speed of 1mm/min, and the force-displacement curve results are shown in fig. 6. Peak load 1171N of the traditional orthogonal layering composite sandwich structure under the same preparation process, and energy absorption 1.054J is achieved in the process; and the peak load 1709N of the sandwich structure of the bionic layering composite material absorbs energy by 1.965J in the process, as shown in fig. 7, the peak load and the energy absorption are respectively improved by 45.9% and 86.4%, and the strengthening and toughening of the whole structure are greatly improved.

Example 2

1) Firstly, carrying out bionic spiral design on the layering sequence of a composite material panel, determining that the spiral period is 2, the spiral angle is 10 degrees, the layer number is even, the layering sequence is [360 degrees/350 degrees/340 degrees/…/20 degrees/10 degrees/0 degrees ] _s, and then carrying out cutting on unidirectional carbon fiber prepreg according to the layering design in a way that the fiber direction is 0 degree and the deflection is gradually 10 degrees;

2) Then, stacking the cut carbon fiber prepregs layer by layer according to the step layering design, performing hot press molding on the stacked prepregs, wherein the molding pressure is 0.2MPa, the heating rate is 5 ℃/min, the molding temperature is 140 ℃, the heat preservation time is 40min, then reducing the temperature to 80 ℃ at the rate of 3 ℃/min, and naturally cooling to room temperature;

3) Finally, cutting the composite material into two panels with the same area, coating the single face with uniform bi-component epoxy resin glue, taking an aramid fiber honeycomb core body, wherein the nominal cell side length is 3.2mm, the height is 20mm, the density is 72kg/m ³, adhering the panels on the upper side and the lower side of the composite material core body with the same area, clamping the adhered composite material honeycomb sandwich plate by using a clamp, curing for 8 hours at normal temperature, and detaching the clamp to obtain the epoxy resin glued full composite material sandwich plate.

Indentation test is carried out on the prepared bionic paving composite material sandwich structure according to ASTM D6264 standard, a hemispherical pressing head is adopted, the diameter is 10mm, the pressing speed is 1mm/min, the force-displacement curve result is shown in FIG. 8, and the peak load 1567N of the traditional orthogonal paving composite material sandwich structure under the same preparation process is energy-absorbed by 1.412J in the process; and the peak load 2136N of the sandwich structure of the bionic layering composite material absorbs energy by 2.323J in the process, as shown in fig. 9, the peak load and the energy absorption are respectively improved by 36.3 percent and 64.6 percent, and the strengthening and toughening of the whole structure are greatly improved.

While the application has been described in terms of the preferred embodiment, it is not intended to limit the application, but it will be apparent to those skilled in the art that variations and modifications can be made without departing from the spirit and scope of the application, and therefore the scope of the application is defined in the appended claims.

Claims (10)

1. An insect exoskeleton morphology layered composite panel, wherein the panel is formed by hot press molding of a plurality of layers of unidirectional fiber prepregs, and if the panel is an even layer composite, the layer-by-layer fiber directions on the panel are arranged in the order [ n×180 °/n×180 ° - θ/n×180 ° -2θ/…/2θ/θ/0 ° ] _s, and if the panel is an odd layer composite, the layer-by-layer fiber directions on the panel are arranged in the order [ (n×180 °/n×180 ° - θ/n×180 ° -2θ/…/2θ/θ/0 ° ] _s/0 °.

2. The panel of claim 1, wherein 5 ° - θ is less than or equal to 30 °, and 180 ° is an integer multiple of θ.

3. The panel of claim 1, wherein the fibers are at least one of: carbon fiber, glass fiber, basalt fiber and natural fiber.

4. A method of making an insect exoskeleton morphologically layered composite panel according to any one of claims 1 to 3, comprising:

Cutting unidirectional fiber prepreg according to the fiber direction of 0 DEG and gradually and linearly increasing deflection theta according to the layering sequence, cutting to obtain 2n+2 prepreg layering if the panel is an even-numbered layer composite material, and cutting to obtain 2n+3 prepreg layering if the panel is an odd-numbered layer composite material;

Stacking the cut prepregs layer by layer according to a layering sequence, performing hot press forming and cooling treatment on the stacked prepregs, wherein the layering sequence is [ n×180 degrees/n×180 degrees-theta/n×180 degrees-2 theta/…/2 theta/0 degrees ] _s for even-layer composite materials; for odd-layer composites, the ply sequence is [ (n x 180/n x 180-theta/n x 180-2 theta/…/2 theta/0 deg.) _s/0 deg. ].

5. The method according to claim 4, wherein the unidirectional fiber prepreg has a mass per unit area of 50 to 250g/m ² and a thickness of 0.05 to 0.25mm.

6. The method according to claim 4, wherein the hot press treatment is an autoclave molding process, the molding pressure is 0.1-0.8 MPa, the heating rate is 1-5 ℃/min, the molding temperature is 125-150 ℃, and the heat preservation time is 0.5-2 h.

7. The method according to claim 4, wherein the cooling treatment is to lower the temperature to 80 ℃ at a rate of 2 to 4 ℃/min, and then naturally cool to room temperature.

8. An insect exoskeleton form high strength and toughness composite sandwich structure, characterized in that the sandwich structure comprises an upper layer and a lower layer of the insect exoskeleton form layered composite panel according to any one of claims 1 to 7, and a honeycomb core body, wherein the honeycomb core body is sandwiched between the two layers of the insect exoskeleton form layered composite panel.

9. The method according to claim 8, wherein the honeycomb core is an aramid honeycomb, the height T of the core is 5-25 mm, the nominal cell side length a is 3-10 mm, the thickness N of the core is 0.1-0.5 mm, and the density is 30-160 kg/m ³.

10. A method of making the insect exoskeleton morphology high strength and toughness composite sandwich structure of claim 8 or 9, comprising:

uniformly coating two-component epoxy resin glue on one side of an upper-layer insect exoskeleton-shaped layered composite material panel and a lower-layer insect exoskeleton-shaped layered composite material panel, and adhering the two-component epoxy resin glue on the upper side and the lower side of a honeycomb core body with the same area;

clamping the attached insect exoskeleton form high-strength and high-toughness composite material sandwich structure by using a clamp, curing at normal temperature for 8-10 h, and detaching the clamp to obtain the epoxy resin bonded insect exoskeleton form high-strength and high-toughness composite material sandwich structure.