Preparation method of quartz fiber reinforced cyanate ester resin-based composite material and antenna housing

Abstract

The invention discloses a preparation method of a quartz fiber reinforced cyanate ester resin matrix composite material and an antenna housing, lower layer demoulding cloth is pasted on the surface of a metal flat plate tool, and cut quartz cyanate ester prepreg is flatly laid on the metal flat plate tool to the required layer number; sequentially laying a layer of upper-layer demolding cloth and a breathable felt on the surface of the quartz cyanate ester prepreg subjected to layer laying, covering the breathable felt with a vacuum bag, tightly adhering the vacuum bag to a metal flat plate tool by using a sealing rubber strip, and then vacuumizing the vacuum bag; and curing the whole in an autoclave to obtain the quartz cyanate resin-based composite material. The prepared quartz cyanate resin-based composite material is high in rigidity, good in toughness and good in bearing performance; the advantages of broadband wave transmission, low dielectric constant and low dielectric loss are realized; the preparation method disclosed by the invention is simple, short in period, low in price, easy to form and easy to process, and can be used for preparing quartz cyanate resin-based composite materials with different shapes and sizes.

Description

Technical Field

[0001] The invention relates to the technical field of resin-based composite materials, and in particular to a preparation method of a quartz fiber reinforced cyanate resin-based composite material and a radome. Background Art

[0002] With the rapid development of radar communication technology and the increasingly harsh environment in which radar antenna covers are used, the comprehensive performance requirements of aircraft for radar antenna covers are gradually increasing, so that they must have excellent characteristics such as high temperature resistance, low dielectric, low loss, high strength, broadband wave transmission, easy molding and easy processing. At present, the wave-transmitting materials of antenna covers are mainly divided into inorganic non-metallic composite materials and organic composite materials. Among them, inorganic non-metallic composite materials are mainly ceramic-based composite materials. Organic composite materials include epoxy resin-based composite materials, phenolic resin-based composite materials, cyanate-based composite materials, etc. Epoxy resin-based composite materials have excellent mechanical properties, wear resistance, chemical corrosion resistance and molding process performance, but their heat resistance is poor, and the dielectric constant and dielectric loss are large, which cannot meet the use requirements of the new generation of radar antenna covers. Although phenolic resin-based composite materials have good heat resistance, corrosion resistance, mechanical properties and molding processing performance, they have the disadvantages of poor weather resistance, easy moisture absorption and release of harmful substances. Summary of the invention

[0003] The purpose of the present invention is to solve the above technical problems and provide a method for quickly preparing a quartz fiber reinforced cyanate resin-based composite material and a radome.

[0004] To achieve the above object, the present invention provides a method for preparing a quartz fiber reinforced cyanate ester resin-based composite material, comprising the following steps:

[0005] 1) Paste the lower layer of release cloth on the surface of the metal flat plate tooling, and lay the cut quartz cyanate prepreg evenly on the metal flat plate tooling to the required number of layers;

[0006] 2) Lay a layer of upper release cloth and breathable felt on the surface of the quartz cyanate prepreg after the layering is completed, cover the breathable felt with a vacuum bag, and use a sealing strip to tightly bond the vacuum bag to the metal flat tooling, and then evacuate the vacuum bag;

[0007] 3) placing the whole in an autoclave for curing to obtain a quartz cyanate resin-based composite material.

[0008] Furthermore, in the step 1), a metal flat plate tooling without pits, protrusions or rust is selected, and is cleaned with a solvent and dried.

[0009] Furthermore, in the step 1), the lower layer of the demoulding cloth is flat and wrinkle-free.

[0010] Furthermore, in the step 2), the vacuum is drawn to a vacuum degree of ≤-100 kPa; while drawing the vacuum, the four corners of the vacuum bag are pressed with a scraper.

[0011] Furthermore, the vacuum requirements, temperature requirements, and pressure requirements of the autoclave in step 3) are as follows:

[0012] Vacuum requirements: vacuum the whole process, vacuum degree ≤-100kPa;

[0013] Temperature requirements: heat to 100℃~120℃ at a heating rate of 1℃ / min~5℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 1h~3h; continue to heat to 150℃~180℃ at a heating rate of 1℃ / min~5℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 2h~6h; continue to heat to 190℃~200℃ at a heating rate of 1℃ / min~3℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 2h~6h; continue to heat to 210℃~220℃ at a heating rate of 1℃ / min~3℃ / min, set the temperature difference at 5℃~10℃, and keep it warm for 2h~8h; after the insulation is completed, cool down to below 50℃ at a cooling rate of 3℃ / min~5℃ / min;

[0014] Pressure requirements: When the insulation temperature reaches 100℃~120℃, start pressurizing, and increase the pressure to 1MPa~1.50MPa at a pressure increase rate of 0.05MPa / min~0.1MPa / min; when the temperature inside the tank drops below 50℃, release the pressure and open the tank, and the pressure reduction rate is 0.05MPa / min~0.1MPa / min.

[0015] Furthermore, before the step 3), the bag-making area on the metal flat plate tooling is polished with coarse and fine sandpapers in sequence, and the bag-making area is cleaned with a solvent until the paper surface remains clean after being wiped with a clean dry wipe paper.

[0016] A radome is also provided, wherein the composite material of the radome is a quartz cyanate resin-based composite material prepared by the above-mentioned preparation method.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: the quartz cyanate ester resin-based composite material prepared by the present invention has high rigidity, good toughness and good load-bearing performance, which solves the technical defects of poor toughness and high brittleness of pure cyanate ester resin; it has the advantages of broadband wave transmission, low dielectric constant and low dielectric loss, and has broad application prospects; and the preparation method of the present invention is simple, short in cycle, low in price, easy to shape and process, and can prepare quartz cyanate ester resin-based composite materials of different shapes and sizes, which is suitable for industrial large-scale production. DETAILED DESCRIPTION

[0018] The present invention will be further described below in conjunction with specific embodiments.

[0019] Cyanate resin has excellent mechanical properties, heat resistance, bonding properties and molding process performance, low dielectric constant (ε = 2.8 ~ 3.2), dielectric loss (tgδ = 2 × 10 -3 ~8×10 -3 ) and moisture absorption performance (<1.5%). However, due to its strong rigidity of molecular structure and high cross-linking density, the material has poor toughness and high brittleness. Quartz fiber has low density, dielectric constant and dielectric loss, and has excellent heat resistance, chemical corrosion resistance and mechanical properties. Therefore, quartz cyanate-based resin composite materials using cyanate resin as matrix and quartz fiber as reinforcement have excellent comprehensive properties and are widely used in important fields such as aviation, aerospace, navigation, and electronic technology.

[0020] The preparation method of the quartz fiber reinforced cyanate ester resin-based composite material of the present invention comprises the following steps:

[0021] 1) Tool cleaning

[0022] Clean the metal flat plate tooling without pits, protrusions or rust with a solvent (such as anhydrous ethanol, acetone or ethyl acetate, etc.) and dry it, then paste the lower layer of mold release cloth with single-sided adhesive on the surface of the metal flat plate tooling. The lower layer of mold release cloth is required to be flat and wrinkle-free.

[0023] 2) Cutting and laying

[0024] Tear off the isolation paper and plastic film on the surface of the cut quartz cyanate prepreg, and then lay the quartz cyanate prepreg evenly on the metal flat plate tooling, lay it to the required number of layers and align it on all sides.

[0025] 3) Vacuum preloading

[0026] On the surface of the quartz cyanate prepreg, lay a layer of upper demoulding cloth and breathable felt in sequence, cover the breathable felt with a vacuum bag, and use sealing strips to tightly bond the vacuum bag to the metal flat plate tooling. Then, evacuate the vacuum bag to a vacuum degree of ≤-100kPa. While evacuating, press the four corners of the vacuum bag with a scraper to avoid bridging.

[0027] 4) Cleaning of bag making area

[0028] Use coarse and fine sandpaper to polish the bag-making area on the metal flat tooling, and clean the bag-making area with a solvent (such as anhydrous ethanol, acetone or ethyl acetate, etc.) until the paper surface remains clean after wiping with clean dry erase paper.

[0029] 5) Curing

[0030] Place the whole in an autoclave. The vacuum, temperature and pressure requirements of the autoclave are as follows:

[0031] Vacuum requirements: vacuum the whole process, vacuum degree ≤-100kPa;

[0032] Temperature requirements: heat to 100℃~120℃ at a heating rate of 1℃ / min~5℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 1h~3h; continue to heat to 150℃~180℃ at a heating rate of 1℃ / min~5℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 2h~6h; continue to heat to 190℃~200℃ at a heating rate of 1℃ / min~3℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 2h~6h; continue to heat to 210℃~220℃ at a heating rate of 1℃ / min~3℃ / min, set the temperature difference at 5℃~10℃, and keep it warm for 2h~8h; after the insulation is completed, cool down to below 50℃ at a cooling rate of 3℃ / min~5℃ / min;

[0033] Pressure requirements: When the insulation temperature reaches 100℃~120℃, start pressurizing, and increase the pressure to 1MPa~1.50MPa at a pressure increase rate of 0.05MPa / min~0.1MPa / min; when the temperature inside the tank drops below 50℃, release the pressure and open the tank, and the pressure reduction rate is 0.05MPa / min~0.1MPa / min.

[0034] 6) Quartz cyanate resin based composite materials

[0035] After curing is completed, the autoclave is taken out, and the vacuum bag, the air-permeable felt, the upper release cloth and the lower release cloth are removed to obtain a quartz cyanate resin-based composite material.

[0036] The quartz cyanate resin-based composite material prepared by the above method can be used for the preparation of radar antenna covers.

Claims

1. A method for preparing a quartz fiber reinforced cyanate ester resin-based composite material, characterized in that: The steps include: 1) Paste the lower layer of release cloth on the surface of the metal flat plate tooling, and lay the cut quartz cyanate prepreg evenly on the metal flat plate tooling to the required number of layers; 2) Lay a layer of upper release cloth and breathable felt on the surface of the quartz cyanate prepreg after the layering is completed, cover the breathable felt with a vacuum bag, and use a sealing strip to tightly bond the vacuum bag to the metal flat tooling, and then evacuate the vacuum bag; 3) placing the whole in an autoclave for curing to obtain a quartz cyanate resin-based composite material.

2. The method for preparing the quartz fiber reinforced cyanate ester resin based composite material according to claim 1, characterized in that: In the step 1), a metal flat plate tooling without pits, protrusions or rust is selected, and is cleaned with a solvent and dried.

3. The method for preparing the quartz fiber reinforced cyanate ester resin based composite material according to claim 1, characterized in that: In the step 1), the lower layer of demoulding cloth is flat and wrinkle-free.

4. The method for preparing the quartz fiber reinforced cyanate ester resin based composite material according to claim 1, characterized in that: In the step 2), the vacuum is evacuated to a vacuum degree of ≤-100 kPa; while evacuating, the four corners of the vacuum bag are pressed with a scraper.

5. The method for preparing the quartz fiber reinforced cyanate ester resin based composite material according to claim 1, characterized in that: The vacuum requirements, temperature requirements and pressure requirements of the autoclave in step 3) are as follows: Vacuum requirements: vacuum the whole process, vacuum degree ≤-100kPa; Temperature requirements: heat to 100℃~120℃ at a heating rate of 1℃ / min~5℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 1h~3h; continue to heat to 150℃~180℃ at a heating rate of 1℃ / min~5℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 2h~6h; continue to heat to 190℃~200℃ at a heating rate of 1℃ / min~3℃ / min, keep the temperature difference at 5℃~10℃, and keep it warm for 2h~6h; continue to heat to 210℃~220℃ at a heating rate of 1℃ / min~3℃ / min, set the temperature difference at 5℃~10℃, and keep it warm for 2h~8h; after the insulation is completed, cool down to below 50℃ at a cooling rate of 3℃ / min~5℃ / min; Pressure requirements: When the insulation temperature reaches 100℃~120℃, start pressurizing, and increase the pressure to 1MPa~1.50MPa at a pressure increase rate of 0.05MPa / min~0.1MPa / min; when the temperature inside the tank drops below 50℃, release the pressure and open the tank, and the pressure reduction rate is 0.05MPa / min~0.1MPa / min.

6. The method for preparing the quartz fiber reinforced cyanate ester resin based composite material according to claim 1, characterized in that: Prior to step 3), the bag-making area on the metal flat plate tooling is polished with coarse and fine sandpapers in turn, and the bag-making area is cleaned with a solvent until the paper surface remains clean after being wiped with a clean dry wipe paper.

7. A radome, characterized in that: The composite material of the antenna cover is a quartz cyanate resin-based composite material prepared by the preparation method described in claim 1.