A wave-transparent composite material with high surface smoothness and low surface roughness and its molding method.

Abstract

This invention relates to a microwave-transparent composite material with high surface smoothness and low surface roughness, and a molding method thereof. The microwave-transparent composite material comprises a fiber-reinforced resin-based microwave-transparent composite material main layer, an ultra-thin fiber cloth-reinforced resin-based microwave-transparent material transition layer, and a thermoplastic film surface layer arranged sequentially. The molding method for this microwave-transparent composite material involves sequentially laying fiber-reinforced resin prepreg (prepreg A), ultra-thin fiber cloth-reinforced resin prepreg (prepreg B), and a thermoplastic polymer film onto a mold, followed by integral hot-pressing and curing. This microwave-transparent composite material exhibits a dense, uniform surface with high smoothness and low roughness.

Description

Technical Field

[0001] This invention belongs to the field of wave-transparent composite material technology, specifically relating to a wave-transparent composite material with high surface flatness and low surface roughness, and a molding method thereof. Background Technology

[0002] Fiber-reinforced resin-based microwave-transparent composites are typical structural / functional integrated materials, primarily used in the fabrication of radar radomes. On one hand, they ensure that electromagnetic signals can pass through the radome efficiently and with low loss; on the other hand, they prevent direct contact between the external environment and the radar system, providing a suitable operating environment for the radar. In the future, as radar system technical specifications continue to rise and the service environment becomes more complex, multi-functional integration requirements such as stealth, lightning protection, anti-static properties, and rain erosion resistance will be placed on TXZ (Radar Radar System). To achieve these requirements, it is generally necessary to construct different functional structures and coatings on the surface of the composite material. However, the original surface of fiber-reinforced resin-based microwave-transparent composites typically contains various defects such as micropores, broken fibers, and low resin content, making it impossible to achieve high-quality construction of functional coatings and structures. Therefore, surface modification of the composite material is necessary.

[0003] While sanding, polishing, and applying putty can improve the surface quality of composite materials, sanding can easily cause fiber breakage and damage, affecting material reliability. Applying putty improves surface smoothness, but results in high surface roughness and poor adhesion between the putty layer and the composite material surface. In summary, there is currently a lack of methods for directly molding wave-transparent composite materials with high surface quality. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention provides a wave-transparent composite material with high surface flatness and low surface roughness, and a molding method thereof.

[0005] In a first aspect, the present invention relates to a microwave-transparent composite material having high surface flatness and low surface roughness, the microwave-transparent composite material comprising a fiber-reinforced resin-based microwave-transparent composite material main layer, an ultra-thin fiber cloth-reinforced resin-based microwave-transparent material transition layer, and a thermoplastic film surface layer arranged in sequence.

[0006] The fibers in the main layer include, but are not limited to, quartz fibers, glass fibers, basalt fibers, PBO fibers, polyimide fibers, and other wave-transparent fibers. The fiber forms include, but are not limited to, chopped fibers, long fibers, and fiber cloth.

[0007] The resins in the main layer and the transition layer are the same, and the types of resins include but are not limited to epoxy resin, cyanate ester resin, phenolic resin, phthalonitrile resin, polyarylene resin, and polyimide resin.

[0008] The ultra-thin fiber cloth in the transition layer includes ultra-thin quartz fiber cloth and ultra-thin glass cloth, and the thickness of the ultra-thin fiber cloth is no more than 0.05 mm.

[0009] The surface layer of the thermoplastic film is made of thermoplastic polymer film, including polyphenolic film, polyurethane film, polystyrene film, polyaryletherketone film, polysulfone film, polyimide film, etc. The temperature resistance of the film must match the temperature resistance of the above-mentioned resin base, and the thickness of the film is not greater than 0.02mm.

[0010] Secondly, this invention discloses an integrated molding method for a wave-transparent composite material with high surface smoothness and low surface roughness. The integrated molding method for the wave-transparent composite material specifically includes the following steps:

[0011] 1) Prepreg A for the main layer of fiber-reinforced resin-based microwave-transparent composite material and prepreg B for the transition layer of ultra-thin fiber cloth-reinforced resin-based microwave-transparent material;

[0012] 2) Lay prepreg A onto the mold surface according to the product design requirements;

[0013] 3) Lay prepreg B over prepreg A;

[0014] 4) Attach the thermoplastic polymer film onto the prepreg B;

[0015] 5) The above-mentioned structure containing prepreg A, prepreg B and thermoplastic polymer film is integrally cured and molded to obtain a wave-transparent composite material with high surface flatness and low surface roughness.

[0016] In step 1), the prepreg A is composed of fibers and resins, wherein the fibers include, but are not limited to, quartz fibers, glass fibers, basalt fibers, PBO fibers, polyimide fibers and other wave-transparent fibers, and the form of the fibers includes, but is not limited to, chopped fibers, long fibers, fiber cloth, etc., and the types of resins include, but are not limited to, epoxy resin, cyanate ester resin, phenolic resin, phthalonitrile resin, polyarylene resin, polyimide resin, etc.

[0017] In step 1), the prepreg B is composed of ultra-thin fiber cloth and resin, wherein the ultra-thin fiber cloth includes ultra-thin quartz fiber cloth and ultra-thin glass cloth, the thickness of the ultra-thin fiber cloth is not greater than 0.05 mm, and the resin is the same as the resin used in prepreg A. In step 3), the number of layers of prepreg B is 1 to 3.

[0018] In step 4), the thermoplastic polymer film includes polyphenolic film, polyurethane film, polystyrene film, polyaryletherketone film, polysulfone film, polyimide film, etc. The temperature resistance of the film must match the temperature resistance of the above-mentioned resin base. The thickness of the film is not greater than 0.02 mm, and the number of film layers is 1.

[0019] In step 5), the curing method is vacuum bag curing, autoclave curing, molding curing, etc., and the curing conditions are matched with the resin used.

[0020] The beneficial effects of this invention are as follows:

[0021] The wave-transparent composite material of the present invention consists of a fiber-reinforced resin-based wave-transparent composite material main layer, an ultra-thin fiber cloth-reinforced resin-based wave-transparent composite material transition layer, and a thermoplastic film surface layer. The wave-transparent composite material has a dense, uniform, highly flat, and low-roughness surface. The transition layer can repair the large-pore defects caused by the fiber weave pattern of the main layer and improve the surface flatness; the surface layer can reduce the surface roughness and improve the surface uniformity. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a wave-transparent composite material with high surface flatness and low surface roughness according to the present invention.

[0023] Figure 2 This is a scanning electron microscope image of the wave-transparent composite material in Example 1.

[0024] Figure 3 This is a three-dimensional contour scan image of the wave-transparent composite material in Example 1.

[0025] Figure 4 This is a scanning electron microscope image of the wave-transparent composite material in Comparative Example 1.

[0026] Figure 5 This is a three-dimensional contour scan image of the wave-transparent composite material in Comparative Example 1. Detailed Implementation

[0027] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0028] The present invention provides a structure of a wave-transparent composite material with high surface smoothness and low surface roughness, as follows: Figure 1 As shown, the microwave-transparent composite material includes a fiber-reinforced resin-based microwave-transparent composite material main layer 1, an ultra-thin fiber cloth-reinforced resin-based microwave-transparent material transition layer 2, and a thermoplastic film surface layer 3 arranged in sequence.

[0029] Example 1:

[0030] Clean the surface of the stainless steel plate mold and apply a release agent; then, lay 10 layers of glass fiber / epoxy resin prepreg (prepreg A) on the surface of the stainless steel plate mold in sequence; then lay 1 layer of ultra-thin glass cloth / epoxy resin prepreg (prepreg B) on the prepreg A; then, apply a thermoplastic polyphenolic film to the prepreg B with a film thickness of 10 μm; finally, use vacuum bag pressing to cure and obtain the wave-transparent composite material with high surface flatness and low surface roughness. Figure 2 Here is a scanning electron microscope image of the wave-transparent composite material. Figure 3 This is a three-dimensional profile scan image of the wave-transparent composite material, which has a surface roughness of 0.4 μm.

[0031] Example 2:

[0032] The surface of the stainless steel plate mold was cleaned and a release agent was applied. Then, 10 layers of quartz fiber cyanate resin prepreg (prepreg A) were sequentially laid on the surface of the stainless steel plate mold. Next, 2 layers of ultra-thin quartz cloth / cyanate resin prepreg (prepreg B) were laid on top of prepreg A. Then, a thermoplastic polyaryletherketone film with a thickness of 15 μm was applied to prepreg B. Finally, the mixture was cured in an autoclave to obtain the high surface smoothness and low surface roughness of the wave-transparent composite material. The surface roughness of this wave-transparent composite material is 0.3 μm.

[0033] Example 3:

[0034] The surface of the stainless steel plate mold was cleaned and a release agent was applied. Ten layers of quartz fiber / polyimide resin prepreg (prepreg A) were then sequentially laid on the surface of the stainless steel plate mold. Next, three layers of ultra-thin quartz cloth / polyimide resin prepreg (prepreg B) were laid on top of prepreg A. Then, a thermoplastic polyimide film with a thickness of 20 μm was applied to prepreg B. Finally, the microwave-transparent composite material with high surface smoothness and low surface roughness was obtained by hot molding and curing. The surface roughness of this microwave-transparent composite material is 0.3 μm.

[0035] Example 4:

[0036] The surface of the stainless steel plate mold was cleaned and a release agent was applied. Then, 10 layers of PBO fiber / cyanate ester resin prepreg (prepreg A) were sequentially laid on the surface of the stainless steel plate mold. Next, 3 layers of ultra-thin quartz cloth / cyanate ester resin prepreg (prepreg B) were laid on top of prepreg A. Finally, a thermoplastic polyaryletherketone film with a thickness of 10 μm was applied to prepreg B. Finally, the mixture was cured in an autoclave to obtain the high surface smoothness and low surface roughness of the wave-transparent composite material. The surface roughness of this wave-transparent composite material is 0.5 μm.

[0037] Comparative Example 1:

[0038] Clean the surface of the stainless steel plate mold and apply a release agent; then lay 10 layers of glass fiber / epoxy resin prepreg (prepreg A) on the surface of the stainless steel plate mold in sequence; finally, use vacuum bag pressing to cure and obtain the wave-transparent composite material. Figure 4 Here is a scanning electron microscope image of the wave-transparent composite material. Figure 5 This is a three-dimensional profile scan image of the wave-transparent composite material, which has a surface roughness of 2.9 μm.

[0039] Comparative Example 2:

[0040] The surface of the stainless steel plate mold was cleaned and a release agent was applied. Then, 10 layers of quartz fiber cyanate resin prepreg (prepreg A) were sequentially laid on the surface of the stainless steel plate mold. Finally, the high surface smoothness and low surface roughness of the wave-transparent composite material were obtained by autoclaving. The surface roughness of the wave-transparent composite material is 3.2 μm.

[0041] Comparative Example 3:

[0042] The surface of the stainless steel plate mold was cleaned and a release agent was applied. Then, 10 layers of quartz fiber / polyimide resin prepreg (prepreg A) were sequentially laid on the surface of the stainless steel plate mold. Finally, the high surface smoothness and low surface roughness of the wave-transparent composite material were obtained by hot molding and curing. The surface roughness of the wave-transparent composite material is 4.5 μm.

[0043] Comparative Example 4:

[0044] The surface of the stainless steel plate mold was cleaned and a release agent was applied. Then, 10 layers of PBO fiber / cyanate ester resin prepreg (prepreg A) were sequentially laid on the surface of the stainless steel plate mold. Finally, the high surface smoothness and low surface roughness of the wave-transparent composite material were obtained by autoclaving. The surface roughness of the wave-transparent composite material is 2.3 μm.

[0045] The specific embodiments of the present invention disclosed above are intended to help understand the content of the present invention and to implement it accordingly. Those skilled in the art will understand that various substitutions, changes, and modifications are possible without departing from the spirit and scope of the present invention. The present invention should not be limited to the content disclosed in the embodiments of this specification; the scope of protection of the present invention is defined by the claims.

Claims

1. A wave-transparent composite material having high surface flatness and low surface roughness, characterized in that, The wave-transparent composite material comprises a main layer of fiber-reinforced resin-based wave-transparent composite material, a transition layer of ultra-thin fiber cloth-reinforced resin-based wave-transparent material, and a surface layer of thermoplastic film arranged in sequence; the resin of the main layer of fiber-reinforced resin-based wave-transparent composite material is the same as that of the transition layer of ultra-thin fiber cloth-reinforced resin-based wave-transparent material; The wave-transparent composite material with high surface flatness and low surface roughness is prepared by the following steps: Prepreg A of the main layer of fiber-reinforced resin-based wave-transparent composite material and prepreg B of the transition layer of ultra-thin fiber cloth-reinforced resin-based wave-transparent material are prepared; The prepreg A is laid on the surface of a mold; The prepreg B is laid on the prepreg A; The thermoplastic polymer film is attached to the prepreg B; The prepreg A, the prepreg B, and the thermoplastic polymer film are integrally cured and formed to obtain the wave-transparent composite material with high surface flatness and low surface roughness; The prepreg B is composed of ultra-thin fiber cloth and resin, the thickness of the ultra-thin fiber cloth is not greater than 0.05 mm, the resin is the same as that used in the prepreg A, and the number of layers of the prepreg B is 1-3.

2. The wave-transparent composite material according to claim 1, characterized in that, The fibers in the main layer of fiber-reinforced resin-based wave-transparent composite material include at least one of the following: quartz fiber, glass fiber, basalt fiber, PBO fiber, and polyimide fiber; the form of the fibers includes at least one of the following: chopped fiber, long fiber, and fiber cloth.

3. The wave-transparent composite material according to claim 1, characterized in that, The resin types of the main layer of fiber-reinforced resin-based wave-transparent composite material and the transition layer of ultra-thin fiber cloth-reinforced resin-based wave-transparent material include at least one of the following: epoxy resin, cyanate ester resin, phenolic resin, phthalonitrile resin, polyarylacetylene resin, and polyimide resin.

4. The wave-transparent composite material according to claim 1, characterized in that, The ultra-thin fiber cloth in the transition layer of ultra-thin fiber cloth-reinforced resin-based wave-transparent material is ultra-thin quartz fiber cloth or ultra-thin glass cloth.

5. The wave-transparent composite material according to claim 1, characterized in that, The surface layer of thermoplastic film uses a thermoplastic polymer film, which includes at least one of the following: polyphenyl oxide film, polyurethane film, polystyrene film, polyaryletherketone film, polysulfone film, and polyimide film; the temperature resistance of the thermoplastic polymer film matches that of the resin base, and the thickness of the thermoplastic polymer film is not greater than 0.02 mm.

6. A method of forming the wave-transparent composite material having high surface flatness and low surface roughness according to claim 1, characterized in that, The following steps are included: Prepreg A of the main layer of fiber-reinforced resin-based wave-transparent composite material and prepreg B of the transition layer of ultra-thin fiber cloth-reinforced resin-based wave-transparent material are prepared; The prepreg A is laid on the surface of a mold; The prepreg B is laid on the prepreg A; The thermoplastic polymer film is attached to the prepreg B; The prepreg A, the prepreg B, and the thermoplastic polymer film are integrally cured and formed to obtain the wave-transparent composite material with high surface flatness and low surface roughness; The prepreg B is composed of ultra-thin fiber cloth and resin, the thickness of the ultra-thin fiber cloth is not greater than 0.05 mm, the resin is the same as that used in the prepreg A, and the number of layers of the prepreg B is 1-3.

7. The molding method according to claim 6, characterized by The prepreg A is composed of fibers and resins, wherein the fibers include at least one of the following: quartz fiber, glass fiber, basalt fiber, PBO fiber, polyimide fiber, and the form of the fibers includes at least one of the following: chopped fiber, long fiber, fiber cloth; the type of the resins includes at least one of the following: epoxy resin, cyanate ester resin, phenolic resin, phthalonitrile resin, polyarylene resin, polyimide resin.

8. The molding method according to claim 6, characterized by The ultra-thin fiber cloth in the prepreg B is an ultra-thin quartz fiber cloth or an ultra-thin glass cloth.

9. The molding method according to claim 6, characterized by, The thermoplastic polymer film includes at least one of the following: polyphenyl ether film, polyurethane film, polystyrene film, polyaryletherketone film, polysulfone film, polyimide film, the temperature resistance of the thermoplastic polymer film matches the temperature resistance of the resin base, the thickness of the thermoplastic polymer film is not more than 0.02mm, and the number of layers of the thermoplastic polymer film is 1 layer.

10. The molding method according to claim 6, characterized by, The curing is at least one of the following: vacuum bag curing, autoclave curing, and mold pressing curing.

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