阅读说明：本技术 一种柔性防热结构 (Flexible heat-proof structure ) 是由 孙健 李正悦 冷劲松 刘彦菊 于 2020-06-04 设计创作，主要内容包括：本发明提供了一种柔性防热结构,包括基底和多个独立设置在所述基底上的防热甲片,所述基底由包括形状记忆聚合物的材料制成,所述防热甲片由防热陶瓷材料制成。本发明采用形状记忆聚合物复合材料为基底,通过改变温度进行二次赋形及形状回复,避免由于变形程度较大而不能使用的问题,从而克服了现有陶瓷瓦由于冷热结构变形不协调而无法在机身变形处使用的缺陷。(The invention provides a flexible heat-proof structure, which comprises a substrate and a plurality of heat-proof armor sheets independently arranged on the substrate, wherein the substrate is made of a material comprising a shape memory polymer, and the heat-proof armor sheets are made of a heat-proof ceramic material. The ceramic tile adopts the shape memory polymer composite material as the substrate, and secondary shaping and shape recovery are carried out by changing the temperature, so that the problem that the ceramic tile cannot be used due to large deformation degree is avoided, and the defect that the existing ceramic tile cannot be used at the deformation position of a machine body due to uncoordinated deformation of a cold and hot structure is overcome.)

1. A flexible thermal protection structure, characterized in that it comprises a substrate (1) and a plurality of thermal protection armour plates (2) independently arranged on said substrate (1), said substrate (1) being made of a material comprising a shape memory polymer and said thermal protection armour plates (2) being made of a thermal protection ceramic material.

2. The flexible thermal protection structure according to claim 1, characterized in that a plurality of said thermal protection armour plates (2) form a thermal protection surface adapted to cover the surface of the substrate (1) in its initial form and the surface of the substrate (1) after deformation.

3. The flexible thermal protection structure according to claim 2, characterized in that a plurality of said thermal protection armour layers (2) are arranged one above the other, the edge portions between two adjacent layers of said thermal protection armour layers (2) being staggered.

4. A flexible thermal protection structure according to claim 3, characterized in that said thermal protection armour plate (2) comprises a thermal insulation plate (21) and an attachment stud (22), said thermal insulation plate (21) being connected to said substrate (1) through said attachment stud (22).

5. Flexible heat protection structure according to claim 4, characterized in that a gap is formed between the insulating panel (21) and the substrate (1), said gap being adapted to provide a space for relative movement between the heat protection armour plate (2) and the substrate (1) when the substrate (1) is deformed.

6. Flexible heat protection structure according to claim 5, characterized in that the distance between the insulating panel (21) and the substrate (1) is 40-50% of the maximum thickness of the insulating panel (21).

7. Flexible heat protection structure according to claim 5, characterized in that the thickness of the insulating panel (21) tapers from a portion close to the connecting column (22) to a portion remote from the connecting column (22).

8. Flexible heat protection structure according to claim 4, characterized in that one end of the connecting stud (22) is glued to the surface of the substrate (1) or embedded inside the substrate (1).

9. The flexible thermal protection structure according to any one of claims 1 to 8, characterized in that there is a positive correlation between the rate of deformation of the substrate (1), the rate of coincidence of a plurality of said thermal protection armour plates (2) and the inclination of the thermal protection armour plates (2) with respect to the substrate (1).

10. The flexible thermal protection structure according to any one of claims 9, wherein the overlapping rate between a plurality of said thermal protection armour plates (2) is 50-75%.

11. The flexible heat protection structure of claim 1, further comprising a heating device for heating said substrate (1), said heating device comprising at least one of an externally applied heating film heating, an embedded resistance wire heating, and an externally applied conductive glue heating.

Technical Field

The invention relates to the technical field of aerospace, in particular to a flexible heat-proof structure.

Background

When the spacecraft is loaded, the spacecraft enters the atmosphere at a high speed, the speed is rapidly reduced under the action of aerodynamic force, meanwhile, the huge kinetic energy and potential energy of the spacecraft are converted into huge heat energy, and the heat-proof structure is used for reducing the heat energy entering the interior of the spacecraft as much as possible, so that the body and internal components of the spacecraft can normally work within a reasonable temperature range. At present, the heat-proof structure of the repeatable heat protection system used by the spacecraft is mainly a ceramic tile heat-proof structure, the service temperature of the ceramic heat-proof tile reaches 1250 ℃, the heat-insulating property is good, and the flight requirement of the space plane can be basically met.

However, the thermal expansion coefficient of the heat-proof tile material is greatly different from that of the aluminum alloy, and a large temperature difference is generated between the heat-proof tile material and the aluminum alloy in the loading process of the aircraft, so a proper gap needs to be reserved between two adjacent heat-proof tiles, and the connection between the heat-proof tiles and the internal structure of the aircraft body needs to be designed with enough elasticity to coordinate the deformation between the heat-proof tiles and the structure, so that the heat-proof structure of the ceramic tile has the defects of brittleness, easiness in falling off, water absorption, no rain protection, easiness in deformation, difficulty in maintenance and replacement and the like.

Disclosure of Invention

The invention aims to solve the following problems to a certain extent: the existing ceramic heat-proof structure has the problems of inconsistent deformation in a cold-hot structure, difficult inspection and maintenance, incapability of responding to the heat-proof requirement in the deformation process and the like.

In order to solve the above problems, the present invention provides a flexible heat protection structure including a substrate made of a material including a shape memory polymer, and a plurality of heat protection armor plates independently disposed on the substrate and made of a heat protection ceramic material.

Optionally, a plurality of the heat protection armor pieces form a heat protection face adapted to cover the surface of the substrate in its original form and the surface of the substrate after deformation.

Optionally, a plurality of the heat-proof armor pieces are stacked layer by layer, and the edge parts between two adjacent layers of the heat-proof armor pieces are covered in a staggered mode.

Optionally, the heat-proof armor plate comprises a heat-proof plate and a connecting column, the heat-proof plate is connected with the substrate through the connecting column, and the heat-proof face of the heat-proof armor plate is formed by a plurality of heat-proof plates.

Optionally, a gap is formed between the heat insulation plate and the substrate, and the gap is suitable for providing a relative movement space between the heat protection armor plate and the substrate when the substrate is deformed.

Optionally, the distance between the thermal shield and the substrate is 40% to 50% of the maximum thickness of the thermal shield.

Optionally, the thickness of the insulating plate tapers from a portion near the connecting column to a portion away from the connecting column.

Optionally, one end of the connecting column is adhered to the surface of the substrate or embedded in the substrate.

Optionally, there is a positive correlation between the rate of deformation of the substrate, the rate of coincidence of the plurality of thermal armour plates and the angle of inclination of the thermal armour plates relative to the substrate.

Optionally, the overlapping rate between a plurality of the heat-proof armor pieces is 50-75%.

Optionally, the flexible heat-proof structure further comprises a heating device for heating the substrate, and the heating device comprises at least one of heating by an externally attached heating film, heating by an internally embedded resistance wire, and heating by externally coated conductive adhesive.

Compared with the prior art, the flexible heat-proof structure provided by the invention has the following advantages:

according to the invention, the shape memory polymer material is used as the substrate, and the heat-proof armor is arranged on the substrate in the fish-scale-like surface structure, so that on one hand, the heat-proof armor is favorable for being used on the surface of the deformation part of the aircraft, and the application scene of the ceramic heat-proof armor is enlarged; on the other hand, the fish scale nail plate design is adopted, the continuity of the surface heat-proof structure can be still kept when the shape memory polymer material substrate deforms, and good heat-proof capability of the deformed structure is provided; in addition, the heat-proof ceramic armor plates are arranged on the substrate independently of each other, and are easy to replace when a single heat-proof armor plate is damaged, so that the defect that the structure of the existing heat-proof device is difficult to inspect and maintain is overcome.

Drawings

FIG. 1 is a schematic structural diagram of a flexible heat shielding structure according to an embodiment of the present invention;

fig. 2 is a second schematic structural view of a flexible heat-proof structure according to an embodiment of the present invention;

FIG. 3(a) is an initial configuration of the thermal protection armor plate by being adhered to the substrate, and FIG. 3(b) is an initial configuration of the thermal protection armor plate by being embedded in the substrate;

FIG. 4(a) is a solid deformation of the thermal protection armor plate by adhering to the substrate, and FIG. 4(b) is a solid deformation of the thermal protection armor plate by embedding in the substrate;

FIG. 5 shows the initial configuration of the flexible thermal shield, (a) bent 30 degrees, (b) bent 60 degrees, and (c) bent 90 degrees;

fig. 6 shows the solid-state deformation of the flexible heat shielding structure, wherein (a) is bent at 30 °, (b) is bent at 60 °, (c) is bent at 90 °.

Description of reference numerals:

1-substrate, 2-heat-proof armor plate, 21-heat-insulating plate and 22-connecting column.

Detailed Description

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

In the coordinate system XYZ provided herein, the X axis represents the right direction in the forward direction, the X axis represents the left direction in the reverse direction, the Y axis represents the rear direction in the forward direction, the Y axis represents the front direction in the reverse direction, the Z axis represents the upper direction in the forward direction, and the Z axis represents the lower direction in the reverse direction. All directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiments of the present invention are only used to explain the relative position relationship between the components, the movement, etc. in a specific posture, and if the specific posture is changed, the directional indicator is changed accordingly, and the connection may be a direct connection or an indirect connection. In addition, the terms "comprising," "including," "containing," and "having" are intended to be non-limiting, i.e., that other steps and other ingredients can be added that do not affect the results. Materials, equipment and reagents are commercially available unless otherwise specified.

In addition, although the invention has described the forms of S1, S2, S3 and the like for each step in the preparation, the description is only for the convenience of understanding, and the forms of S1, S2, S3 and the like do not represent the limitation of the sequence of each step.

Because the ceramic heat-proof tile (i.e. the heat-proof armor plate) and the machine body structure (such as an aluminum alloy or composite material structure) have very different coefficients of linear expansion, and the ceramic heat-proof tile and the machine body structure have temperature difference of hundreds or thousands of degrees when entering the machine body structure, a connecting piece with larger elastic deformation is needed between the ceramic tile and the machine body structure to coordinate the deformation between the ceramic tile and the structure, in addition, the machine body structure is not allowed to bear the deformation when the mechanical load is stressed, and the connection piece is also needed to coordinate, so that the deformation of the structure caused by heat and force is effectively prevented from being transmitted to the ceramic tile to cause damage. In the prior art, a rigid ceramic heat-proof tile and a fuselage skin are bonded together indirectly by using a strain isolation pad, and the strain isolation pad is usually made of a fiber felt with certain strength and flexibility; however, for the space expansion structure, the local deformation degree is large, and the deformation degree of the strain isolation pad cannot be completely matched with the expansion structure, so that the use scene of the ceramic heat-proof tile is limited.

In order to solve the problems, the invention provides a flexible heat-proof structure, which adopts a shape memory polymer composite material as a substrate, utilizes the characteristics of secondary shaping and shape recovery of the shape memory polymer, and arranges a ceramic tile on the substrate in a fish-scale-like shape, thereby realizing better heat-proof capability under the deformation condition.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.

Referring to fig. 1 and 2, the embodiment of the invention provides a flexible heat protection structure, which comprises a substrate 1 and a plurality of heat protection armor plates 2 independently arranged on the substrate 1, wherein the substrate 1 is made of a material comprising a shape memory polymer, and the heat protection armor plates 2 are made of a heat protection ceramic material.

The principle of "deformation" of the shape memory polymer composite substrate is as follows: when the temperature reaches above the glass transition temperature Tg of the shape memory polymer, applying an external force to the material to deform the material; under the condition of keeping the shape unchanged, reducing the temperature of the glass transition temperature to a certain temperature below Tg, keeping for a period of time, removing external restraint, and keeping the given deformation unchanged (deformation shape); when the temperature is raised above the glass transition temperature Tg again, the shape memory polymer returns to its original shape (recovered state), thereby completing the deformation cycle of "original state-deformed state-recovered state".

Based on this, adopt the material of shape memory polymer to make substrate 1, this substrate 1 and space development structure after expanding shape phase-match, after reaching its glass transition temperature, become soft and take shape to the form after space development structure draws in, cool and harden under keeping the restraint condition, the rigidity and intensity when returning the normal temperature, it becomes "fixed deformation form", after substrate 1 heats again and reaches the glass transition temperature, can return to the original shape from "fixed deformation form". Therefore, the shape memory polymer composite material is used as the substrate 1, compared with the existing strain isolation pad, the shape memory polymer composite material can be better attached to the complex surface of an aircraft, the problem that the ceramic tile cannot be used due to large deformation degree is avoided, and the defect that the existing ceramic tile cannot be used at the deformation position of the aircraft body due to the fact that the cold-hot structure deforms incoordinatively is overcome.

It should be noted that the heat-proof armor plate can be adhered to the shape memory polymer substrate 1 through the solidified glue in the traditional way, meanwhile, a proper gap is left between two adjacent heat-proof armor plates, and the gap is filled with a high-temperature-resistant material, so that the damage to the heat-proof armor plate caused by the large difference of the expansion coefficients of the cold and hot structures is avoided. Of course, the heat-proof armor plate can be arranged on the substrate in other ways as long as the heat-insulating effect is achieved.

In an embodiment of the invention, the plurality of heat shield armor sheets 2 form a heat shield face adapted to cover the surface of the substrate 1 in its original form and the deformed surface of the substrate 1. Here, the initial form surface of the substrate 1 is also the form of the substrate 1 matching the shape of the expanded space expanded structure, and the deformed surface of the substrate 1 is a "fixed deformation form", that is, a form of the expanded space structure after being folded. From this, through the setting of injecing heat protection second sheet 2, realize that heat protection second sheet 2 covers to aircraft outer wall all-round around warping, effectively isolated convection heat transfer and radiation heat transfer have satisfied the heat protection demand of texturing machine.

In order to adapt to the deformation of the substrate 1 made of the shape memory polymer material, the inventor creatively utilizes the bionic principle to design the heat-proof armor pieces 2 on the substrate 1 in a fish scale-like surface structure mode.

As shown in fig. 1, the heat-proof nail plate 2 may have a plate-shaped structure with at least one end being in a circular arc shape, and the surface thereof is coated with a radiation coating, that is, the heat-proof nail plate 2 may have a structure with a transverse cross section (a plane where the XY axes are located in fig. 1) being in a circular shape or an elliptical shape, or may have a structure with one end of the transverse cross section being in a trapezoidal shape and the other end being in a circular arc shape, and may be designed into different shapes according to requirements, in short, the shape of the heat-proof nail plate 2 is favorable for being. In addition, the initial shape of the substrate 1 is the complex surface of the aircraft, the fixed deformation state of the substrate is the complex surface of the aircraft, and both the initial shape and the fixed deformation state can be designed at will according to actual requirements. For convenience of description, in the embodiment of the present invention, the substrate 1 of the heat shielding structure made of the shape memory polymer material has a rectangular cross section, a straight initial shape, and a curved or bent fixed shape after shaping.

Specifically, each heat-proof armor piece 2 is independently fixed on the substrate 1, the plurality of heat-proof armor pieces 2 are distributed in an array, for convenience of description, the heat-proof armor pieces 2 in the embodiment are arranged layer by layer from left to right, that is, when the substrate 1 deforms, the heat-proof armor pieces 2 can incline towards the upper right relative to the substrate 1, and the orientation directions of the plurality of heat-proof armor pieces 2 are the same; the edge parts between two adjacent layers of the heat-proof armor pieces 2 are covered in a staggered way, namely the heat-proof armor piece 2 of the first layer is positioned at the position above the two heat-proof armor pieces 2 of the next layer (the second layer), and the edge parts of the lower left corner and the upper left corner of the two heat-proof armor pieces 2 are respectively covered; in the same column, the heat shield deck 2 on the first layer partially covers the top edge of the heat shield deck 2 on the third layer below the second layer.

Therefore, the embodiment of the invention adopts the shape memory polymer material as the substrate 1, and the heat-proof armor sheet 2 is arranged on the substrate 1 in the fish scale-like surface structure, on one hand, the heat-proof armor sheet 2 is favorable for being used on the surface of the deformation part of the aircraft, and the application scene of the ceramic heat-proof sheet is enlarged; on the other hand, by adopting the design of the scaly nail, the continuity of the surface heat-proof structure can be still kept when the shape memory polymer material substrate 1 deforms, and good heat-proof capability of the deformed structure is provided; in addition, the heat-proof ceramic armor plates are independently arranged on the substrate 1 made of the shape memory polymer material, and are easy to replace when a single heat-proof armor plate 2 is damaged, so that the defect that the structure of the existing device is difficult to inspect and maintain is overcome.

Of course, although one embodiment of the present invention defines a plurality of heat-proof armor pieces 2 arranged in a layer-by-layer stacking manner, the edge portions between two adjacent layers of heat-proof armor pieces 2 are covered in a staggered manner; in other embodiments, a combination of layer-by-layer design and pasting design may also be adopted, such as the first and second layers of heat-proof armor being stacked one on top of another and covering the left end portion of the third layer of heat-proof armor, the third layer of heat-proof armor being directly pasted on the substrate 1, the fourth and fifth layers of heat-proof armor being stacked one on top of another and covering the right end portion of the third layer of armor. In another embodiment, the heat-proof armor plate 2 can also adopt other arrangement modes as long as the continuity of the surface heat-proof surface can be maintained when the substrate 1 deforms, and the convection heat transfer and the radiation heat transfer can be effectively isolated.

The shape memory polymer comprises a matrix material and a reinforcing material, wherein the matrix material comprises epoxy resin or cyanate ester, the lower limit of the transition temperature Tg of the matrix material is 80 ℃, and the upper limit of the transition temperature Tg of the matrix material is 500 ℃; the reinforcing material includes at least one of carbon fiber, glass fiber, aramid fiber, graphene, and carbon nanotube.

The flexible heat-shielding structure provided by the present invention further comprises a heating means (not shown in the drawings) for heating the substrate 1. The temperature of the substrate 1 can be controlled by the heating device, the substrate 1 is in a flat state in an initial state, the heating device heats the substrate 1, when the temperature of the substrate 1 rises and exceeds the glass transition temperature Tg of the shape memory polymer, the substrate 1 is converted into a flexible state, the substrate 1 is bent or folded under the action of external force, after the substrate is bent to a preset shape, the heating device stops heating, the substrate 1 is recovered to a rigid state, the external force is removed, the substrate 1 is kept bent and folded, the substrate 1 is attached to the outer surface of the deformation part of the aircraft and is in a folded state, the folded state can reduce the unfolded area of the aircraft, the aircraft is folded into a small volume, the aircraft can conveniently penetrate through the atmosphere of the earth, after the aircraft penetrates through the atmosphere, when the unfolding device is unfolded, the heating device is controlled to heat the substrate 1 again, when the substrate 1 reaches and exceeds the glass transition temperature Tg of the shape memory, the base 1 automatically returns to the initial state, thereby adapting to the unfolding deformation requirements of the aircraft.

The heating device comprises at least one of heating by externally pasting a heating film, heating by internally burying a resistance wire and heating by externally coating a conductive adhesive. In the embodiment of the present invention, preferably, an embedded resistance wire is used for heating, that is, the resistance wire is embedded during the pouring process of the substrate 1, so as to control the temperature of the substrate 1.

Referring to fig. 2, the heat shield armor plate 2 includes a heat shield plate 21 and a connection column 22, the heat shield plate 21 is connected to the substrate 1 through the connection column 22, and the plurality of heat shield plates 21 form a heat shield surface of the heat shield armor plate 2. Through setting up spliced pole 22, heat insulating board 21 does not directly contact basement 1, not only prevents basement 1 effectively and gives heat insulating board 21 and causes the destruction because of the deformation transmission that heat, power produced, still provides the air insulating layer simultaneously, has improved the whole heat protection effect of flexible heat protection structure.

Wherein the diameter of the connecting column 22 or the maximum width of the transverse section (the plane formed by the XY axes in fig. 1) needs to be considered in combination with the overall overlapping rate and the overall structural strength of the thermal shield nail 2, in the embodiment of the present invention, the diameter of the connecting column 22 is preferably 10% of the maximum length of the thermal shield plate 21X in the axial direction.

The connecting column 22 and the heat insulation plate 21 are integrally designed, that is, the heat insulation plate 21 and the connecting column 22 are both made of a heat-proof ceramic material by burning, wherein the heat-proof ceramic material comprises one of a full-silica fiber type material, a silica fiber and alumina fiber mixed type material, a silica fiber, an alumina fiber and a borosilicate fiber type alumina material.

Due to the connecting column 22 arranged between the heat insulation plate 21 and the substrate 1, a gap is formed between the heat insulation plate 21 and the substrate 1, and when the substrate 1 deforms, the gap is suitable for providing a relative movement space between the heat protection armor plate 2 and the substrate 1. From this, when the aircraft is out of shape to basement 1 following, the heat protection armour 2 of imitative fish scale shape structure can be in the space activity of reserving, sets up like this and has improved the deformation harmony between heat protection armour 2 and the basement 1, and then has reduced the stress effect, has strengthened the overall structure intensity and the anti-destruction ability of flexible heat protection structure.

Preferably, in the embodiment of the present invention, the distance between the thermal insulation board 21 and the substrate 1 is 40% to 50% of the maximum thickness of the thermal insulation board 21, in combination with the deformability of the substrate 1 and the efficiency of the intermediate air barrier.

Further, the thickness of the insulation panel 21 is gradually thinner from a portion near the connection column 22 to a portion far from the connection column 22. Therefore, the whole weight of the flexible heat-proof structure can be reduced under the condition of meeting the heat-proof requirement, and the light-weight requirement of the aircraft is met.

Since the shape memory polymer substrate 1 is linearly elastic, the thermal protection armor plates 2 are fixed on the substrate 1, and the change of the interlayer distance between the thermal protection armor plates 2 is linearly related to the change of the substrate 1. The following description will be made by taking the fixed form of the substrate 1 as an elongated state as an example:

referring to fig. 3 and 4, the length of the thermal protection armor plate 2 on the X axis is 1 unit length, the interval between the initial thermal protection armor plates 2 is 0.25 unit length, and the overlapping rate of the thermal protection armor plate 2 is 75% of the area of the thermal protection armor plate 2; after the solid deformation is formed, the interval between the heat-proof armor sheets 2 is 0.5 unit length, the overlapping rate of the heat-proof armor sheets 2 is 50%, and the area change rate of the substrate 1 can reach 200%. The initial inclination angle of a single heat-proof armor piece 2 is 15 degrees, when a plurality of heat-proof armor pieces 2 are stacked layer by layer and arranged, the inclination angle is changed to 20 degrees through extrusion, after the area of the substrate 1 is changed by 200 percent, the coincidence rate of the heat-proof armor pieces 2 is 50 percent, at the moment, the extrusion is eliminated, and the inclination angle is changed to 15 degrees. It can be seen that the deformation rate of the substrate, the overlapping rate of the heat-proof armor plates and the inclination angle of the heat-proof armor plates relative to the substrate are in positive correlation.

Of course, the substrate 1 may be bent at any position, and as shown in fig. 5 and 6, fig. 5 shows an initial deformation form of the flexible heat shielding structure with a coverage rate of 50%, in which the overlapping rate of the heat shielding armor plates 2 is 75%, and fig. 6 shows a solid deformation form of the flexible heat shielding structure, in which the overlapping rate of the heat shielding armor plates 2 is 50%, it can be seen that the substrate 1 may be deformed at any position and has uniformity as a whole.

According to the flexible heat-proof structure provided by the embodiment of the invention, the shape memory characteristic of the substrate 1 and the fish scale-like design of the heat-proof armor sheet 2 are utilized, the heat-proof tile can cover the outer wall of the aircraft in an all-around manner, the convection heat transfer and the radiation heat transfer are effectively isolated, and the heat-proof requirement of a deformed structure is met.

Preferably, the coincidence rate of the plurality of heat-proof armor plates 2 is 50% -75%, so that the phenomenon that gaps occur among the plurality of heat-proof armor plates 2 in the deformation process of the substrate 1 to cause the metal surface of the aircraft to be exposed, heat flow directly enters the body structure to melt the body structure, and finally the aircraft is disassembled due to the serious damage of the structure can be avoided; meanwhile, the condition that the plurality of heat-proof armor pieces 2 are stacked too densely is avoided, and the deformation coordination is reduced.

The heat insulation board 21 is fixed on the substrate 1 through the connection column 22, and one end of the connection column 22 is fixedly connected with the heat insulation board 21, and the other end is stuck on the surface of the substrate 1 through an adhesive, or fixed on the surface of the substrate 1 through a curing glue (as shown in fig. 3a and fig. 4 a), or embedded inside the substrate 1 in the forming stage of the substrate 1 (as shown in fig. 3b and fig. 4 b).

Wherein, the step of curing and connecting through silica gel comprises the following steps: 1) fixing the relative position of the heat-proof armor sheet 2 and the substrate 1, 2) gluing at the joint, and 3) waiting for curing; the curing speed depends on the thickness of the curing system, the temperature and the humidity of the silicone rubber layer, and the curing process can be accelerated by increasing the temperature and the humidity of the environment. Usually, at 25 ℃ and a relative humidity of 50% RH, the surface drying time is generally 3-20 minutes, more than 15 hours are needed for the rubber to become elastic, and various performances of the rubber can reach the best state after seven days. The silica gel curing connection has the advantages of convenience in molding and convenience in design.

And the step of inline connection includes: 1) fixing the preset relative position of the heat-proof armor sheet 2, and 2) pouring the base 1 for molding, so that one end of the connecting column 22 of the heat-proof armor sheet 2 is embedded into the base 1. The embedded connection has the advantages that the strength of the joint is better than that of the silica gel curing, the process steps are simplified, meanwhile, stress generated by the contact part of the substrate 1 and the silica gel during deformation is avoided, and the overall strength of the flexible heat-proof structure is increased to a certain extent.

The flexible heat-proof structure provided by the embodiment of the invention has the advantages of simple and convenient preparation method and simple structure, utilizes the shape memory effect of the shape memory polymer and the characteristics of high specific strength and specific rigidity thereof, combines the shape memory polymer with the rigid heat-proof ceramic, adopts the shape memory polymer composite material as the substrate 1, and provides the heat-proof requirement of a deformed structure by changing the temperature to carry out secondary shaping and shape recovery; meanwhile, the fish scale-shaped heat-proof armor pieces 2 are adopted, so that the continuity of the surface heat-proof structure can be still kept when the substrate 1 deforms, good heat-proof capability of the deformation structure is provided, and a new thought and method are provided for the design of the future heat-proof structure of the aircraft.

Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.