Sandwich composite having high thermal conductivity and manufacturing method therefor
The sandwich composite with prepreg laminates and honeycomb structure, stitched and thermally cured, addresses low thermal conductivity and mechanical degradation issues, achieving improved thermal conductivity and strength for space applications.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- INDUSTRYACADEMIC COOPERATION FOUNDATION GYEONGSANG NATIONAL UNIVERSITY
- Filing Date
- 2025-09-11
- Publication Date
- 2026-05-07
AI Technical Summary
Existing sandwich composites used in space applications face challenges with low thermal conductivity in the thickness direction while maintaining mechanical performance, and conventional methods to enhance thermal conductivity degrade mechanical properties.
A thermally conductive sandwich composite is manufactured by stacking prepreg laminates with a honeycomb structure and stitching through the laminates and honeycomb, using materials like polyacrylonitrile-based carbon fibers and adhesive films, with controlled stitching intervals and thermal curing to improve thermal conductivity and mechanical strength.
The composite achieves enhanced thermal conductivity and bending stiffness with improved mechanical strength, maintaining structural integrity and efficient heat dissipation.
Smart Images
Figure KR2025014200_07052026_PF_FP_ABST
Abstract
Description
High thermal conductivity sandwich composite and method for manufacturing the same
[0001] The present invention claims the benefit of the filing date of Korean Patent Application No. 10-2024-0151329 filed with the Korean Intellectual Property Office on October 30, 2024, the entire contents of which are incorporated into the present invention.
[0002] The present invention relates to a thermally conductive sandwich composite comprising a prepreg laminate and a honeycomb structure, and a method for manufacturing the same.
[0003]
[0004] Carbon fiber reinforced plastic (CFRP) is used in various fields ranging from transportation, construction, marine, electrical, electronic, aviation, and space industries due to its excellent specific stiffness and specific strength, as well as its excellent corrosion resistance, fatigue characteristics, and lightweight properties.
[0005] The most commonly used carbon fiber reinforced plastics are polyacrylonitrile (PAN)-based carbon fiber reinforced plastics and pitch-based carbon fiber reinforced plastics. Polyacrylonitrile (PAN)-based carbon fiber reinforced plastics are manufactured using polyacrylonitrile and exhibit excellent strength and modulus, but have the problem of low thermal conductivity. In addition, pitch-based carbon fiber reinforced plastics are manufactured using petroleum pitch and are inexpensive and exhibit excellent strength, but have the problem of difficult manufacturing process control and difficulty in ensuring uniformity.
[0006] However, due to the rapid temperature changes in the space environment, it is necessary to rapidly dissipate heat to protect the structural stability and internal electronic equipment of spacecraft and satellites, and to implement composite materials with uniform mechanical properties. To this end, sandwich composites containing honeycomb structures are widely used, and it is widely known that such structures possess excellent bending stiffness and strength. However, sandwich composites have a limitation in that their heat transfer performance in the thickness direction is low.
[0007] Conventionally, to solve this problem, techniques have been proposed to improve the thermal conductivity of sandwich composite structures by machining holes in them and using fasteners. However, this approach has the problem that the mechanical performance of the sandwich composite structure is significantly degraded.
[0008] Therefore, there is a need for a sandwich composite structure with excellent thermal conductivity while maintaining a similar level of mechanical performance to existing sandwich composite structures.
[0009]
[0010] The problem that the present invention aims to solve is to provide a thermally conductive sandwich composite material having excellent thermal conductivity, bending stiffness, and strength, and a method for manufacturing the same.
[0011] However, the problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below.
[0012]
[0013] According to one aspect of the present invention, a thermally conductive sandwich composite is provided, comprising: a first prepreg laminate; a second prepreg laminate; a honeycomb structure comprising a plurality of unit cells aligned in a vertical direction and positioned between the first prepreg laminate and the second prepreg laminate; and a stitching portion stitched through the first prepreg laminate, the second prepreg laminate and the honeycomb structure.
[0014] According to another aspect of the present invention, a method for manufacturing a thermally conductive sandwich composite is provided, comprising the steps of: stacking a plurality of prepregs to manufacture a first prepreg laminate and a second prepreg laminate, respectively; positioning a honeycomb structure containing a plurality of unit cells between the first prepreg laminate and the second prepreg laminate such that the plurality of unit cells are aligned in a vertical direction to form a sandwich laminate; stitching the sandwich laminate to form a stitched portion penetrating the first prepreg laminate, the second prepreg laminate, and the honeycomb structure; and heating and curing the sandwich laminate with the stitched portion formed therein.
[0015]
[0016] A thermally conductive sandwich composite according to one embodiment of the present invention may have excellent thermal conductivity in the thickness direction and in-plane direction.
[0017] A thermally conductive sandwich composite according to one embodiment of the present invention may have excellent bending stiffness and strength.
[0018] The effects of the present invention are not limited to those described above, and unmentioned effects will be clearly understood by those skilled in the art from this specification.
[0019]
[0020] FIG. 1 is a schematic perspective view of a thermally conductive sandwich composite according to one embodiment of the present invention.
[0021] FIG. 2 is a schematic side cross-sectional view of a thermally conductive sandwich composite according to one embodiment of the present invention of FIG. 1.
[0022] FIG. 3 is a side cross-sectional view schematically showing the heat transfer path of a thermally conductive sandwich composite according to one embodiment of the present invention of FIG. 1.
[0023] FIG. 4 is a perspective view schematically illustrating the manufacturing process of a thermally conductive sandwich composite according to one embodiment of the present invention.
[0024] Figure 5 shows the results of measuring the thermal conductivity in the thickness direction of the thermally conductive sandwich composites prepared in Examples 1-1 to 1-3 and Comparative Example.
[0025]
[0026] When a part of the entire specification is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.
[0027] Throughout the present specification, terms including ordinal numbers, such as “first” and “second,” are used for the purpose of distinguishing one component from another and are not limited by said ordinal numbers. For example, within the scope of the invention, the first component may also be named the second component, and similarly, the second component may be named the first component.
[0028] Throughout the entire specification, “thickness direction” and “laminar direction” indicate the direction in which prepregs are laminated to form layers, and specifically, may mean the direction from one side where one prepreg and another prepreg come into contact to the other side of the other prepreg.
[0029] Throughout this specification, "in-plane direction" refers to a direction orthogonal to the thickness direction (lamination direction).
[0030] Throughout this specification, when a component is described as being located "on" another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components.
[0031] The configuration of a specific embodiment of the present invention will be described in detail below with reference to the attached drawings. Here, it should be noted that when assigning reference numerals to the components of each drawing, identical components are denoted by the same numeral whenever possible, even if they are shown in different drawings.
[0032]
[0033] A thermally conductive sandwich composite according to one embodiment of the present invention comprises: a first prepreg laminate; a second prepreg laminate; a honeycomb structure comprising a plurality of unit cells aligned in a vertical direction located between the first prepreg laminate and the second prepreg laminate; and a stitching portion stitched through the first prepreg laminate, the second prepreg laminate and the honeycomb structure.
[0034] According to one embodiment of the present invention, the thermally conductive sandwich composite may further include an adhesive film positioned between the first prepreg laminate, the second prepreg laminate, and the honeycomb structure, respectively. By including the adhesive film, a thermally conductive sandwich composite with excellent interlayer bonding strength can be manufactured. The adhesive film may be any commonly used one and is not subject to any particular limitations. For example, the adhesive film may include one or more of an epoxy resin, a polyimide resin, and a benzocyclobutene resin. By including the above materials, a thermally conductive sandwich composite with high temperature stability can be manufactured.
[0035] According to one embodiment of the present invention, the first prepreg laminate and the second prepreg laminate of the thermally conductive sandwich composite may each comprise two or more prepregs including carbon fibers and thermosetting resins. Specifically, the carbon fibers may be polyacrylonitrile-based carbon fibers. By including polyacrylonitrile-based carbon fibers in the prepregs, a thermally conductive sandwich composite with excellent fatigue properties and environmental resistance can be manufactured. Specifically, a thermally conductive sandwich composite that is resistant to moisture and ultraviolet rays and exhibits minimal degradation of physical properties even under repeated loading can be manufactured.
[0036] According to one embodiment of the present invention, the prepreg may include a thermosetting resin. Specifically, the thermosetting resin may include one or more of epoxy resin, polyester resin, vinyl ester resin, phenolic resin, benzoxazine resin, and bismaleimide resin. By including the thermosetting resin in the prepreg, a thermally conductive sandwich composite material with uniform strength and stiffness, i.e., mechanical properties, can be manufactured.
[0037] According to one embodiment of the present invention, the honeycomb structure refers to a structure comprising a plurality of unit cells of a honeycomb structure having an open cell structure. By using the honeycomb structure, a thermally conductive sandwich composite having high strength relative to its weight can be realized, and excellent thermal insulation performance can be achieved.
[0038] According to one embodiment of the present invention, the material of the honeycomb structure may be selected from aluminum, aramid fiber paper, glass fiber reinforced composite material, and carbon fiber reinforced composite material. When the material of the honeycomb structure is aramid fiber paper, a product from Nomex may be used. Specifically, when the above-described material is used as the honeycomb structure, a thermally conductive sandwich composite with excellent thermal conductivity, heat resistance, and chemical resistance can be realized.
[0039] FIG. 1 is a schematic perspective view of a thermally conductive sandwich composite according to one embodiment of the present invention.
[0040] As seen in FIGS. 1a and 1b, the thermally conductive sandwich composite (1000) comprises prepreg (100), a honeycomb structure (300), and a stitching portion (200). Specifically, the thermally conductive sandwich composite (1000) comprises a first prepreg laminate (101) in which two or more prepregs (100) are stacked; a honeycomb structure (300) comprising a plurality of vertically aligned unit cells stacked on the first prepreg laminate (101); and a second prepreg laminate (102) in which two or more prepregs (100) are stacked on the honeycomb structure (300), and a stitching portion (200) that is stitched through the first prepreg laminate (101), the second prepreg laminate (102), and the honeycomb structure (300).
[0041] The stitching portion (200, 201) may include pitch-based carbon fiber or copper wire. Specifically, referring to FIG. 1a, the stitching portion (200) may be stitched in a spaced-apart manner. By stitching the stitching portion (200) in a spaced-apart manner, thermal conductivity in the thickness direction can be improved. Furthermore, a thermally conductive sandwich composite with excellent bending stiffness and strength can be realized. Alternatively, referring to FIG. 1b, the stitching portion (201) may be stitched continuously in a spaced manner. By stitching the stitching portion (201) continuously in a spaced manner, thermal conductivity in the thickness direction can be improved. Furthermore, a thermally conductive sandwich composite with excellent bending stiffness and strength can be realized.
[0042] FIG. 2 is a schematic cross-sectional view of a thermally conductive sandwich composite (1000) according to one embodiment of the present invention of FIG. 1.
[0043] Referring to FIG. 2a, the stitching portion (200) is stitched in a spaced-apart manner, and the end of the stitching portion may protrude outward from the composite material and be bent toward the outer surface of the first prepreg laminate (101) and the outer surface of the second prepreg laminate (102). The protruding end may be bent toward the outer surface of the first prepreg laminate (101) and the outer surface of the second prepreg laminate (102) to improve thermal conductivity toward the surface of the thermally conductive sandwich composite (1000).
[0044] Referring to FIG. 2b, the pitch-based carbon fibers or copper wires forming the stitching portion (201) may be in a form that is continuously connected at intervals. By continuously connecting the stitching portion (201) in the direction of the outer surface of the first prepreg laminate (101) and the outer surface of the second prepreg laminate (102), the thermal conductivity in the in-plane direction of the thermally conductive sandwich composite (1000) can be improved.
[0045] The stitching interval of the stitching portion (201) may be 1 to 3 times the unit cell diameter of the honeycomb structure (300). Specifically, the stitching interval of the stitching portion (201) may be 1 to 2 times the unit cell diameter of the honeycomb structure (300). By forming the stitching portion (201) in the thermally conductive sandwich composite (1000) within the aforementioned range, the thermal conductivity, bending stiffness, and strength in the thickness direction of the thermally conductive sandwich composite (1000) can be improved.
[0046] FIG. 3 is a side cross-sectional view schematically showing the heat transfer path of a thermally conductive sandwich composite according to one embodiment of the present invention of FIG. 1.
[0047] According to one embodiment of the present invention with reference to FIG. 3a, a thermal path can be formed along the stitching portion (200) in the in-plane direction and thickness direction of the thermally conductive sandwich composite material (1000).
[0048] According to one embodiment of the present invention with reference to FIG. 3b, a thermal path can be formed along the stitching portion (201) in the in-plane direction and thickness direction of the thermally conductive sandwich composite material (1000).
[0049] A method for manufacturing a thermally conductive sandwich composite according to another aspect of the present invention comprises the steps of: stacking a plurality of prepregs to manufacture a first prepreg laminate and a second prepreg laminate, respectively; positioning a honeycomb structure containing a plurality of unit cells between the first prepreg laminate and the second prepreg laminate such that the plurality of unit cells are aligned in a vertical direction to form a sandwich laminate; and stitching the sandwich laminate to form a stitched portion penetrating the first prepreg laminate, the second prepreg laminate, and the honeycomb structure.
[0050] According to one embodiment of the present invention, the method for manufacturing the thermally conductive sandwich composite may further include the step of positioning an adhesive film on a first prepreg laminate and a second prepreg laminate. Specifically, by positioning the adhesive film on the first prepreg laminate and the second prepreg laminate, the adhesive film can be positioned between the first prepreg laminate and the second prepreg laminate and the honeycomb structure in the formed sandwich laminate, thereby enabling the manufacture of a thermally conductive sandwich composite with excellent interlayer bonding strength.
[0051] The details regarding the prepreg, prepreg laminate, honeycomb structure, stitching part, and sandwich laminate in the manufacturing method of the present invention are as described above.
[0052] FIG. 4 is a perspective view schematically illustrating the manufacturing process of a thermally conductive sandwich composite according to one embodiment of the present invention.
[0053] Referring to FIG. 4, one embodiment of the present invention manufactures a first prepreg laminate (101) and a second prepreg laminate (102) by stacking a plurality of prepregs (100). According to one embodiment of the present invention, the first prepreg laminate (101) and the second prepreg laminate (102) may be manufactured in the same way. An adhesive film (400) is placed on each of the first prepreg laminate (101) and the second prepreg laminate (102) that are facing each other.
[0054] Then, a honeycomb structure (300) containing a plurality of unit cells is positioned between the first prepreg laminate (101) and the second prepreg laminate (102), each having an adhesive film (400) located thereon, such that the plurality of unit cells are aligned in a vertical direction to form a sandwich laminate. At this time, the honeycomb structure (300) is positioned so that the respective adhesive film (400) located on the first prepreg laminate (101) and the second prepreg laminate (102) comes into contact with each other to form a sandwich laminate.
[0055] Then, the sandwich laminate is stitched to form a stitched portion (200) that penetrates the first prepreg laminate (101), the second prepreg laminate (102), and the honeycomb structure (300).
[0056] According to one embodiment of the present invention, the method may further include a step of heating and curing the sandwich laminate having the stitching portion (200) formed therein. The thermally conductive sandwich composite can be integrated due to the thermal curing step. Specifically, through the thermal curing step, the prepreg included in the thermally conductive sandwich composite can be cured into the form of carbon fiber reinforced plastic (CFRP), thereby enabling the production of a sandwich composite with excellent mechanical performance.
[0057] According to one embodiment of the present invention, the curing may be performed by heating at a temperature of 50°C to 150°C. Specifically, the curing may be performed in a first curing step and a second curing step. The second curing step may be performed at a temperature range higher than the temperature range of the first curing step. More specifically, the first curing step may be performed at 50°C to 100°C, 50°C to 90°C, 60°C to 100°C, 60°C to 80°C, or 70°C to 90°C, and the second curing step may be performed at 100°C to 150°C, 100°C to 140°C, 100°C to 130°C, 110°C to 150°C, 110°C to 140°C, or 110°C to 130°C. The first curing step and the second curing step may be performed continuously. By performing the first curing step and the second curing step within the temperature ranges described above, the thermosetting resin contained in the prepreg can be easily cured and the thermosetting resin can be firmly cured. Through the above-mentioned thermal curing, the above-mentioned thermally conductive sandwich composite material that simultaneously exhibits thermal conductivity and load-bearing performance can be provided.
[0058] According to one embodiment of the present invention, the curing may be performed for a period of 100 to 150 minutes. By performing thermal curing within the aforementioned time range, the thermosetting resin contained in the prepreg can be easily cured and the thermosetting resin can be firmly cured. Through the thermal curing, the thermally conductive sandwich composite material that simultaneously exhibits thermal conductivity and load-bearing performance can be provided.
[0059] According to one embodiment of the present invention, the thermal curing process may be a co-curing method. By adopting the method described above, a thermally conductive sandwich composite with excellent mechanical and thermal properties can be produced. Specifically, by simultaneously curing the heat-dissipating multifunctional composite without a separate individual curing process, the manufacturing process steps can be shortened, thereby providing superior efficiency in composite manufacturing compared to the conventional secondary bonding method. The secondary bonding method may refer to curing a first prepreg laminate and a second prepreg laminate, then laminating the cured first prepreg laminate, an adhesive film, a honeycomb structure, and the cured second prepreg laminate, and undergoing a curing process again. Furthermore, by utilizing the co-curing method, the heat transfer path and the composite structure can be manufactured as a single unit, thereby providing the heat-dissipating multifunctional composite with excellent bending stiffness and strength.
[0060]
[0061] Hereinafter, the present invention will be described in detail through examples and experimental examples to specifically explain the invention. However, the examples and experimental examples according to the present invention may be modified in various different forms, and the scope of the present invention is not to be interpreted as being limited to the examples and experimental examples described below. The examples and experimental examples of this specification are provided to more completely explain the present invention to those with average knowledge in the art.
[0062]
[0063] Example 1-1. Preparation of a thermally conductive sandwich composite
[0064]
[0065] Manufacture of prepreg laminates
[0066] Polyacrylonitrile-based carbon fiber / epoxy prepreg (WSN-3K, SK Chemical) was prepared with dimensions of 140 mm x 140 mm x 0.19 mm in width x thickness.
[0067] The above-described prepregs were each repeatedly stacked eight sheets to manufacture a first prepreg laminate and a second prepreg laminate with a thickness of 1.52 mm.
[0068]
[0069] Manufacture of sandwich laminates
[0070] An adhesive film (FM® 94-1M Adhesive Film, Solvay) was laminated onto one side of each of the first prepreg laminate and the second prepreg laminate prepared above. A sandwich composite was manufactured by laminating and bonding the surfaces of the first prepreg laminate and the second prepreg laminate, on which the adhesive film was laminated, with a plurality of unit cells of an aluminum honeycomb structure (density 6.1 lb / ft³, cell diameter 1 / 8 inch, cell height 1 inch, Texas Almet) in a vertical direction.
[0071]
[0072] Manufacturing of sandwich composites
[0073] The prepared sandwich laminate was stitched with pitch-based carbon fiber (XN-90-60S, Nippon Graphite Fiber) to form intermittently spaced stitching sections. The stitching spacing was 1 / 8 inch, which is the cell diameter of the aluminum honeycomb structure, and the stitching was performed so that the pitch-based carbon fiber penetrated the interior of the unit cell of the aluminum honeycomb structure.
[0074]
[0075] A thermally conductive sandwich composite was manufactured by performing a first curing of the above-mentioned stitched sandwich laminate at 80°C for 15 minutes using an autoclave, followed by a second curing at 120°C for 120 minutes. Additionally, during the thermal curing process, the two ends of the stitched pitch-based carbon fibers protruding outside the sandwich composite through the open cells of the honeycomb structure of the sandwich composite were compressed under a vacuum with a pressure of 3 atmospheres to bend and fix them toward the outer surface direction of the thermally conductive sandwich composite, that is, toward the outer surface of the first prepreg laminate and the outer surface direction of the second prepreg laminate. At this time, the ends of the pitch-based carbon fibers were bent in a radial shape.
[0076]
[0077] Examples 1-2 to 1-3, Comparative Example 1
[0078] The thermally conductive sandwich composites of Examples 1-2 to 1-3 and Comparative Example 1 were manufactured using the same method as the method for manufacturing the thermally conductive sandwich composite of Example 1, except that the presence or absence of stitching and the stitching spacing were adjusted as shown in Table 1 below.
[0079]
[0080] Stitching Performed (Presence / Absence) Stitching Spacing (inch) Example 1-1 ○ 1 / 8 Example 1-2 ○ 2 / 8 Example 1-3 ○ 3 / 8 Comparative Example 1 Х-
[0081]
[0082] Experimental Example 1: Measurement of Thermal Conductivity in the Thickness Direction of a Thermally Conductive Sandwich Composite
[0083] To measure the thickness-direction thermal conductivity of the thermally conductive sandwich composites prepared in Examples 1-1 to 1-3 and Comparative Example 1, a heat source of 100°C was connected to the thermally conductive sandwich composites, and the time taken until the temperature converged and the convergence temperature were measured. The results are shown in Table 2 and Figure 5 below.
[0084] Figure 5 shows the results of measuring the thermal conductivity in the thickness direction of the thermally conductive sandwich composites prepared in Examples 1-1 to 1-3 and Comparative Example.
[0085]
[0086] Convergence Temperature (°C) Time Required (s) Example 1-186.8343 Example 1-279.5300 Example 1-377.5297 Comparative Example 174.3325
[0087]
[0088] Looking at Table 2 and Figure 5, it was confirmed that Examples 1-1, 1-2, and 1-3, which were stitched with pitch-based carbon fibers, had excellent thermal conductivity in the thickness direction compared to Comparative Example 1, which was not stitched.
[0089] Specifically, Examples 1-2 and 1-3, which were stitched with pitch-based carbon fibers, were superior to Comparative Example 1, which was not stitched, in terms of both time required and convergence temperature, indicating that they have excellent thermal conductivity.
[0090] In the case of Example 1-1, the time required to reach the convergence temperature is somewhat longer than that of Comparative Example 1, which did not perform stitching; however, considering that the convergence temperature is significantly higher, it can be concluded that Example 1-1, which performed stitching, has superior thermal conductivity compared to Comparative Example 1, which did not perform stitching.
[0091] In addition, by comparing Examples 1-1 to 1-3, it can be seen that the thermal conductivity in the thickness direction increases as the stitching interval becomes shorter.
[0092] Specifically, it can be observed that the convergence temperature increases as the stitching spacing becomes narrower. In this case, considering that the heat transfer rate does not change when stitching is performed using the same material, the fact that the time required to reach the convergence temperature increases can be concluded to mean that the thermal conductivity is superior as the stitching spacing becomes narrower.
[0093] Although the present invention has been described above by limited embodiments, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs.
[0094]
[0095] [Explanation of the symbol]
[0096] 1000: Thermally conductive sandwich composite
[0097] 100: Prepreg
[0098] 101: First prepreg laminate
[0099] 102: Second prepreg laminate
[0100] 200: Stitching section
[0101] 201: Stitching section
[0102] 300: Honeycomb structure
[0103] 400: Adhesive film
[0104] 500: Heat transfer path
Claims
1. First prepreg laminate; 2nd prepreg laminate; A honeycomb structure comprising a plurality of unit cells aligned in a vertical direction, located between the first prepreg laminate and the second prepreg laminate; and A thermally conductive sandwich composite comprising: a stitching portion stitched through the first prepreg laminate, the second prepreg laminate, and the honeycomb structure.
2. In Paragraph 1, A thermally conductive sandwich composite further comprising an adhesive film positioned between the first prepreg laminate, the second prepreg laminate, and the honeycomb structure, respectively.
3. In Paragraph 1, A thermally conductive sandwich composite, wherein the first prepreg laminate and the second prepreg laminate each comprise one or more laminated prepregs including polyacrylonitrile-based carbon fibers and thermosetting resins.
4. In Paragraph 1, A thermally conductive sandwich composite, wherein the material of the above honeycomb structure is selected from aluminum, aramid fiber paper, glass fiber reinforced composite material and carbon fiber reinforced composite material.
5. In Paragraph 1, The above-mentioned stitching portion comprises a pitch-based carbon fiber or copper wire, and is a thermally conductive sandwich composite.
6. In Paragraph 1, The above stitching portion is stitched in segments with gaps, and A thermally conductive sandwich composite, wherein the end of the stitching portion protrudes to the outside of the composite and is bent in the direction of the outer surface of the first prepreg laminate and the outer surface of the second prepreg laminate.
7. In Paragraph 1, A thermally conductive sandwich composite having a stitching spacing of the above-mentioned stitching portion that is 1 to 3 times the unit cell diameter of the above-mentioned honeycomb structure.
8. A step of manufacturing a first prepreg laminate and a second prepreg laminate, respectively, by stacking a plurality of prepregs; A step of forming a sandwich laminate by positioning a honeycomb structure comprising a plurality of unit cells between the first prepreg laminate and the second prepreg laminate such that the plurality of unit cells are aligned in a vertical direction; and A method for manufacturing a thermally conductive sandwich composite according to claim 1, comprising the step of stitching the sandwich laminate to form a stitched portion penetrating the first prepreg laminate, the second prepreg laminate, and the honeycomb structure.
9. In Paragraph 8, A method for manufacturing a thermally conductive sandwich composite material, further comprising the step of heating and curing the sandwich laminate in which the stitching portion is formed.
10. In Paragraph 9, A method for manufacturing a thermally conductive sandwich composite, wherein the curing is performed at a temperature of 50°C to 150°C for a time of 100 minutes to 150 minutes.