Preparation method for rapidly forming needled and stitched quartz composite ceramic radome

Abstract

The invention belongs to the technical field of radome processing, and particularly relates to a preparation method for rapidly forming a needled and stitched quartz composite ceramic radome. Comprising the following steps: S1, pretreating a woven piece fabric, and putting the pretreated woven piece fabric into a sealable soaking container; s2, adding silica sol, soaking under a vacuum condition, taking out, and immediately putting in a supercritical CO2 environment; s3, taking out the woven piece cloth, and needling and sewing to obtain a preform; s4, after sewing is completed, the prefabricated body and the mold are put into a drying oven together to be subjected to thermocuring treatment, demolding is conducted after thermocuring treatment is completed, and an antenna housing rough blank is obtained; and S5, the antenna housing rough blank is subjected to precision machining. According to the invention, the structural characteristics of the ceramic composite material are utilized, and the radome weaving and compounding scheme is redefined, so that the composite ceramic material has good density and material uniformity after weaving is completed. The production and preparation time of the composite ceramic antenna housing is greatly shortened, and the uniformity and material performance of the composite ceramic are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of antenna cover processing, and in particular relates to a preparation method for rapid prototyping of a needle-stitched quartz composite ceramic antenna cover. Background Art

[0002] The composite ceramic radome is at the front end of the missile. It is mainly responsible for the aerodynamic shape of the missile head during flight, protecting the internal guidance system while not hindering the normal operation of the guidance system. To complete this task, the radome must have good anti-ablation, heat protection, load-bearing and wave-transmitting capabilities.

[0003] With the evolution of modern combat systems, missile requirements have shifted from high precision, high speed, and precision-guided missiles to a need for large quantities of low-cost, rapidly prototyping precision-guided missiles. The missile's nose radome also needs to meet low-cost, rapidly prototyping requirements to keep pace with military demands. Existing composite ceramic radomes are primarily manufactured and laminated through repeated densification of woven parts. However, repeated lamination has the disadvantages of slow densification, long production cycles, and high costs. Furthermore, the lengthy lamination process for composite ceramic radomes can lead to material uniformity issues, which can negatively impact the radome's wave transmission.

[0004] Based on this, we proposed a method for rapid prototyping of needle-stitched quartz composite ceramic antenna covers, hoping to solve the shortcomings of the existing technology. Summary of the Invention

[0005] The purpose of the present invention is to address the existing problems and provide a method for preparing a needle-stitched quartz composite ceramic antenna cover by rapid prototyping.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0008] S1. After pre-treating the woven fabric, place it in a sealable soaking container;

[0009] S2. Evacuate the immersion container, add silica sol, and soak the woven fabric under vacuum conditions. After completion, take it out and immediately place it in a supercritical CO2 environment for 1 to 2 hours;

[0010] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0011] S4. After the stitching is completed, the preform and the mold are placed in an oven for heat curing. After the preform is cooled to room temperature, it is demoulded to obtain a rough radome blank.

[0012] S5. Perform precision machining on the radome rough blank.

[0013] Furthermore, the woven fabric in step S1 is one of a quartz antenna cover multi-layer cloth cover, quartz fiber cloth, and quartz felt.

[0014] Furthermore, the pretreatment method described in step S1 is: the woven fabric is ultrasonically cleaned in anhydrous ethanol for 10 to 15 minutes, dried, and then placed in a low-temperature plasma device for treatment under an argon atmosphere for 30 to 60 seconds. After completion, it is taken out for use.

[0015] Furthermore, the power of the plasma treatment in step (1) is 50-60 W, the argon flow rate is 100-200 sccm, and the vacuum degree of the chamber is maintained at ≤100 Pa during the treatment process.

[0016] Furthermore, the preparation method of the silica sol described in step S2 is: adding 6~8% of mesoporous silica nanoparticles to the basic silica sol, ultrasonically dispersing it evenly, then dropwise adding 4~5% of the weight of the basic silica sol by weight of ZIF-8 methanol solution, stirring continuously at 150~250r / min for 1~2h, then adding 2.5~3% of the weight of the basic silica sol by weight of PNIPAM aqueous solution, stirring and mixing, and adjusting the pH to 4~5 with hydrochloric acid, heating to 50°C, reacting for 2~3h, cooling to room temperature, adding 0.6~0.8% of the weight of the basic silica sol by weight of a photoinitiator, stirring in the dark until completely dissolved, and finally adding 1.5~2% of the weight of the basic silica sol by weight of Fe3O4@SiO2 particles, and ultrasonically dispersing them evenly.

[0017] Furthermore, the molar concentration of the ZIF-8 methanol solution is 0.1 mol / L;

[0018] The mass fraction of PNIPAM (poly N-isopropylacrylamide) aqueous solution is 10~12%;

[0019] The photoinitiator is benzoin dimethyl ether.

[0020] Furthermore, the vacuum condition in step S2 is -0.07 to -0.095 MPa, and the soaking time is 30 to 90 minutes.

[0021] Furthermore, the placing in the supercritical CO2 environment for 1~2 hours described in step S2 is specifically as follows: the woven fabric after the silica sol soaking treatment is placed in an autoclave, the autoclave body is sealed, the autoclave is heated to 35~40°C at 3~5°C / min, liquid CO2 is injected, and the pressure is increased to 10~15MPa at a rate of 1~2MPa / min. The temperature and pressure conditions are maintained for 1~2 hours. After the treatment is completed, the pressure is released at a rate of 0.2~0.5MPa / min, and it is taken out after being released to normal pressure.

[0022] Furthermore, the heat curing treatment described in step S4 is specifically as follows: placing the preform and the mold together in an oven, first heating to 35°C at 3-4°C / min, maintaining for 1-2 hours, and then continuing to heat to 120°C and maintaining for 4-5 hours.

[0023] Furthermore, the precision machining in step S5 is grinding and polishing.

[0024] Compared with the prior art, the present invention has the following advantages:

[0025] 1. This invention leverages the structural properties of ceramic composite materials and redefines the radome weaving and compounding scheme, resulting in excellent density and uniformity of the composite ceramic material upon completion. Furthermore, material properties can be technically adjusted to meet diverse product requirements. This significantly reduces the production time of the composite ceramic radome and improves the uniformity and material properties of the composite ceramic.

[0026] 2. The present invention performs plasma surface modification treatment before the immersion treatment. The high-energy particles in the argon plasma etch the surface of the quartz fiber to form a nano-scale rough structure, which increases the mechanical bite area between the fiber and the silica sol. At the same time, the plasma bombardment introduces active groups such as hydroxyl (-OH) and carboxyl (-COOH), which bond with the -SiOH groups in the silica sol through hydrogen bonds, thereby improving the interfacial bonding strength and effectively reducing delamination defects. The silica sol soaking treatment is performed under vacuum conditions. The base silica sol fills the micron-scale pores between the fibers, while mesoporous nano-silica fills the nano-scale pores, helping to improve density. The ZIF-8 precursor decomposes at 120°C to produce ZnO nanoparticles, which ionically bond with the quartz fibers and the silica sol to form a ceramic bridge, thereby improving interfacial bonding and shear strength. The PNIPAM polymer and photoinitiator interact with each other to adjust the curing temperature, causing a phase transition in the PNIPAM molecules and chain contraction, which dramatically increases the sol viscosity and accelerates curing. Under UV light, the photoinitiator generates active free radicals, which trigger condensation of the silica sol's hydroxyl groups, shortening the curing time and improving product processing efficiency. Following the soaking process, the supercritical CO2 treatment is performed. The supercritical fluid has extremely strong penetrating power, pushing the silica sol deep into the nano-scale pores within the fiber bundle, increasing densification efficiency by 50%. This also avoids the fiber damage caused by traditional high-temperature solvent evaporation and ensures uniform material density. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of a soaking container;

[0028] Figure 2 Schematic diagram of soaking the fabric for a woven piece;

[0029] Figure 3 It is a structural diagram of the weaving tool and the weaving process;

[0030] In the figure: 1. Soaking container, 2. Soaking container end cover, 3. Pressure gauge, 4. Vacuum tube, 5. Feed pipe, 6. Valve, 7. Braided fabric, 8. Silica sol, 9. Silica sol sprayer, 10. Braiding mold, 11. Suture thread, 12. Suture needle, 13. Fixed insert, 14. Rotating shaft, 15. Internal suture mold, 16. Imitation mold, 17. Braided fabric after supercritical CO2 treatment. DETAILED DESCRIPTION

[0031] In order to further explain the present invention, it is described below with reference to the following specific embodiments.

[0032] Experimental reagents

[0033] Basic silica sol (DuPont (USA), Ludox CL-X), mesoporous silica nanoparticles (Hangzhou Jikang New Materials Co., Ltd.), benzoin dimethyl ether (Shanghai Sengexin Polymer Materials Co., Ltd.), Fe3O4@SiO2 particles (Jiangsu Xianfeng Nanomaterials Technology Co., Ltd.).

[0034] Note: Unless otherwise specified, the raw materials used in the present invention are all conventional products purchased from the market.

[0035] Example 1

[0036] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0037] S1. The woven fabric is ultrasonically cleaned in anhydrous ethanol for 10 minutes, dried, and then placed in a low-temperature plasma device under an argon atmosphere for 30 seconds. After completion, the woven fabric is taken out and placed in a sealable immersion container 1;

[0038] The power of the plasma treatment is 50W, the argon flow rate is 100 sccm, and the vacuum degree of the chamber is maintained at ≤100 Pa during the treatment;

[0039] S2. Evacuate the immersion container 1 to -0.07 MPa, then add silica sol and soak the woven fabric under vacuum conditions for 30 minutes. Take it out and immediately put it into the autoclave. Seal the autoclave, heat the autoclave to 35°C at 3°C / min, inject liquid CO2, and increase the pressure to 10 MPa at a rate of 1 MPa / min. Maintain this temperature and pressure condition for 1 hour. After the treatment is completed, release the pressure at a rate of 0.2 MPa / min until it returns to normal pressure and then take it out;

[0040] The silica sol preparation method comprises the following steps: adding 6% of mesoporous silica nanoparticles to a base silica sol, uniformly dispersing the particles with ultrasonic dispersion, dropwise adding a ZIF-8 methanol solution (molar concentration of 0.1 mol / L) at a concentration of 4% by mass of the base silica sol, continuously stirring at 150 r / min for 1 hour, then adding a PNIPAM aqueous solution (mass fraction of 10%) at a concentration of 2.5% by mass of the base silica sol, stirring and mixing, adjusting the pH to 4 with hydrochloric acid, heating to 50° C., reacting for 2 hours, cooling to room temperature, adding benzoin dimethyl ether at a concentration of 0.6% by mass of the base silica sol, stirring in the dark until the particles are completely dissolved, and finally adding Fe3O4@SiO2 particles at a concentration of 1.5% by mass of the base silica sol, and uniformly dispersing the particles with ultrasonic dispersion;

[0041] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0042] S4. After the stitching is completed, the preform and the mold are placed in an oven, and the temperature is first raised to 35°C at a rate of ~4°C / min, maintained for 1 hour, and then further raised to 120°C and maintained for 4 hours. After completion, the preform is cooled to room temperature and demolded to obtain the radome blank;

[0043] S5. Grind and polish the rough antenna cover.

[0044] Example 2

[0045] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0046] S1. The woven fabric is ultrasonically cleaned in anhydrous ethanol for 12 minutes, dried, and then placed in a low-temperature plasma device under an argon atmosphere for 45 seconds. After completion, the woven fabric is taken out and placed in a sealable immersion container 1;

[0047] The power of the plasma treatment is 55W, the argon flow rate is 150sccm, and the vacuum degree of the chamber is maintained at ≤100Pa during the treatment;

[0048] S2. Evacuate the immersion container 1 to -0.08 MPa, then add silica sol, soak the woven fabric under vacuum conditions for 60 minutes, take it out and immediately put it into the autoclave, seal the autoclave, heat the autoclave to 37°C at 4°C / min, inject liquid CO2, and increase the pressure to 12 MPa at a rate of 1.5 MPa / min. Maintain this temperature and pressure condition for 1.5 hours. After the treatment is completed, release the pressure at a rate of 0.3 MPa / min, and take it out after it is released to normal pressure.

[0049] The silica sol preparation method comprises the following steps: adding 7% of mesoporous silica nanoparticles to a base silica sol, uniformly dispersing the particles by ultrasonication, dripping a ZIF-8 methanol solution (molar concentration of 0.1 mol / L) at 4.5% by mass of the base silica sol, continuously stirring at 200 r / min for 1.5 hours, then adding a PNIPAM aqueous solution (mass fraction of 11%) at 2.7% by mass of the base silica sol, stirring and mixing, adjusting the pH to 4.5 with hydrochloric acid, heating to 50° C., reacting for 2.5 hours, cooling to room temperature, adding benzoin dimethyl ether at 0.7% by mass of the base silica sol, stirring in the dark until the particles are completely dissolved, and finally adding Fe3O4@SiO2 particles at 1.7% by mass of the base silica sol, and uniformly dispersing the particles by ultrasonication.

[0050] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0051] S4. After the stitching is completed, the preform and the mold are placed in an oven, and the temperature is first raised to 35°C at 3.5°C / min, maintained for 1.5 hours, and then further raised to 120°C and maintained for 4.5 hours. After completion, the preform is cooled to room temperature and demolded to obtain the radome blank;

[0052] S5. Grind and polish the rough antenna cover.

[0053] Example 3

[0054] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0055] S1. The woven fabric is ultrasonically cleaned in anhydrous ethanol for 15 minutes, dried, and then placed in a low-temperature plasma device under an argon atmosphere for 60 seconds. After completion, the woven fabric is taken out and placed in a sealable immersion container 1;

[0056] The power of the plasma treatment is 60W, the argon flow rate is 200sccm, and the vacuum degree of the chamber is maintained at ≤100Pa during the treatment;

[0057] S2. Evacuate the immersion container 1 to -0.095 MPa, then add silica sol, soak the woven fabric under vacuum conditions for 90 minutes, take it out and immediately put it into the autoclave, seal the autoclave, heat the autoclave to 40°C at 5°C / min, inject liquid CO2, and increase the pressure to 15 MPa at a rate of 2 MPa / min. Maintain this temperature and pressure condition for 2 hours. After the treatment is completed, release the pressure at a rate of 0.5 MPa / min, and take it out after it is released to normal pressure.

[0058] The silica sol preparation method comprises the following steps: adding 8% of mesoporous silica nanoparticles to a base silica sol, uniformly dispersing the particles with ultrasonic dispersion, dropwise adding a ZIF-8 methanol solution (molar concentration of 0.1 mol / L) at a concentration of 5% by mass of the base silica sol, continuously stirring at 250 r / min for 2 hours, then adding a PNIPAM aqueous solution (mass fraction of 12%) at a concentration of 3% by mass of the base silica sol, stirring and mixing, adjusting the pH to 5 with hydrochloric acid, heating to 50° C., reacting for 3 hours, cooling to room temperature, adding benzoin dimethyl ether at a concentration of 0.8% by mass of the base silica sol, stirring in the dark until the particles are completely dissolved, and finally adding Fe3O4@SiO2 particles at a concentration of 2% by mass of the base silica sol, and uniformly dispersing the particles with ultrasonic dispersion;

[0059] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0060] S4. After the stitching is completed, the preform and the mold are placed in an oven, and the temperature is first raised to 35°C at 4°C / min, maintained for 2 hours, and then further raised to 120°C and maintained for 5 hours. After completion, the preform is cooled to room temperature and demolded to obtain the radome blank;

[0061] S5. Grind and polish the rough antenna cover.

[0062] The present invention cuts quartz fiber cloth, woven quartz cloth cover, and quartz felt according to the shape structure and size of the required cover to obtain the woven fabric required for the antenna cover. After the woven fabric is cleaned with anhydrous ethanol, it is dried and subjected to low-temperature plasma treatment in an argon atmosphere. The high-energy particles in the plasma will etch the fiber surface to form a nano-scale rough structure, and at the same time introduce active groups such as hydroxyl (-OH) and carboxyl (-COOH) to improve the interface bonding strength between the fiber and the silica sol, effectively reducing the delamination defect. After treatment, the woven fabric 7 is added to the soaking container 1 and covered with a soaking container. The container end cap 2 and the soaking container end cap 2 together form a vacuum-sealed soaking container. A pressure gauge 3, a vacuum tube 4, a feed pipe 5, and a valve 6 are provided on the soaking container end cap 2. The soaking container 1 is evacuated through the vacuum tube 4 to remove the air in the soaking container. The silica sol 8 enters the soaking container 1 through the feed pipe 5. The soaking container 1 is connected to / closed by the valve 6 and the soaking container 1 is connected to the outside. The soaking treatment is carried out under vacuum conditions. During the soaking process, the pressure in the soaking container 1 is observed and monitored by the pressure gauge 3. The pre-soaking ensures that the cover body has a certain material strength after the weaving is completed. The soaking container end cap 2 is opened, taken out and immediately placed in an autoclave. The autoclave body is sealed and subjected to supercritical CO2 treatment. After the treatment is completed, the pressure is released to normal pressure. The supercritical fluid has extremely strong penetration ability and can push the silica sol deep into the nano-scale pores inside the fiber bundle, thereby improving the densification efficiency and avoiding the fiber damage problem caused by traditional high-temperature evaporation solvents. After supercritical CO2 treatment, the woven fabric is taken out and then woven and stitched according to the required external dimensions of the antenna cover. During the weaving process, the woven fabric 17 treated with supercritical CO2 is stitched by a weaving mold 10, a guide stitching needle 12, and a stitching thread 11, while ensuring the external contour and curve of the antenna cover, and ensuring the shape curve basic mold of the antenna cover woven part through the internal stitching mold 15 and the profiling mold 16. At the same time, it is connected to the rotating shaft 14 through a fixed insert 13. During the weaving process, it is rotated and adjusted in position as needed so that the area to be woven of the antenna cover woven part is in the working area of ​​the stitching device. During the stitching process, a silica sol sprayer 9 is used to spray silica sol intermittently through a reciprocating motion to keep the fabric moist and prevent the silica sol from solidifying, so that the woven fabric cannot be woven due to the solidification of the silica sol. After stitching and weaving, the preform and the mold are placed in an oven together for heat curing treatment. After completion, it is cooled to room temperature and demolded to obtain the rough antenna cover, which is then ground and polished to obtain the finished antenna cover.

[0063] Comparative Example 1

[0064] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0065] S1, placing the woven fabric in a sealable soaking container 1;

[0066] S2. Evacuate the immersion container 1 to -0.08 MPa, then add silica sol, soak the woven fabric under vacuum conditions for 60 minutes, take it out and immediately put it into the autoclave, seal the autoclave, heat the autoclave to 37°C at 4°C / min, inject liquid CO2, and increase the pressure to 12 MPa at a rate of 1.5 MPa / min. Maintain this temperature and pressure condition for 1.5 hours. After the treatment is completed, release the pressure at a rate of 0.3 MPa / min, and take it out after it is released to normal pressure.

[0067] The silica sol preparation method comprises the following steps: adding 7% of mesoporous silica nanoparticles to a base silica sol, uniformly dispersing the particles by ultrasonication, dripping a ZIF-8 methanol solution (molar concentration of 0.1 mol / L) at 4.5% by mass of the base silica sol, continuously stirring at 200 r / min for 1.5 hours, then adding a PNIPAM aqueous solution (mass fraction of 11%) at 2.7% by mass of the base silica sol, stirring and mixing, adjusting the pH to 4.5 with hydrochloric acid, heating to 50° C., reacting for 2.5 hours, cooling to room temperature, adding benzoin dimethyl ether at 0.7% by mass of the base silica sol, stirring in the dark until the particles are completely dissolved, and finally adding Fe3O4@SiO2 particles at 1.7% by mass of the base silica sol, and uniformly dispersing the particles by ultrasonication.

[0068] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0069] S4. After the stitching is completed, the preform and the mold are placed in an oven, and the temperature is first raised to 35°C at 3.5°C / min, maintained for 1.5 hours, and then further raised to 120°C and maintained for 4.5 hours. After completion, the preform is cooled to room temperature and demolded to obtain the radome blank;

[0070] S5. Grind and polish the rough antenna cover.

[0071] Comparative Example 2

[0072] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0073] S1. The woven fabric is ultrasonically cleaned in anhydrous ethanol for 12 minutes, dried, and then placed in a low-temperature plasma device under an argon atmosphere for 45 seconds. After completion, the woven fabric is taken out and placed in a sealable immersion container 1;

[0074] The power of the plasma treatment is 55W, the argon flow rate is 150sccm, and the vacuum degree of the chamber is maintained at ≤100Pa during the treatment;

[0075] S2. Evacuate the immersion container 1 to -0.08 MPa, then add silica sol and soak the woven fabric in vacuum for 60 minutes. After releasing the vacuum, heat the container to evaporate the water in the silica sol and remove the woven fabric after completion.

[0076] The silica sol preparation method comprises the following steps: adding 7% of mesoporous silica nanoparticles to a base silica sol, uniformly dispersing the particles by ultrasonication, dripping a ZIF-8 methanol solution (molar concentration of 0.1 mol / L) at 4.5% by mass of the base silica sol, continuously stirring at 200 r / min for 1.5 hours, then adding a PNIPAM aqueous solution (mass fraction of 11%) at 2.7% by mass of the base silica sol, stirring and mixing, adjusting the pH to 4.5 with hydrochloric acid, heating to 50° C., reacting for 2.5 hours, cooling to room temperature, adding benzoin dimethyl ether at 0.7% by mass of the base silica sol, stirring in the dark until the particles are completely dissolved, and finally adding Fe3O4@SiO2 particles at 1.7% by mass of the base silica sol, and uniformly dispersing the particles by ultrasonication.

[0077] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0078] S4. After the stitching is completed, the preform and the mold are placed in an oven, and the temperature is first raised to 35°C at 3.5°C / min, maintained for 1.5 hours, and then further raised to 120°C and maintained for 4.5 hours. After completion, the preform is cooled to room temperature and demolded to obtain the radome blank;

[0079] S5. Grind and polish the rough antenna cover.

[0080] Comparative Example 3

[0081] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0082] S1. The woven fabric is ultrasonically cleaned in anhydrous ethanol for 12 minutes, dried, and then placed in a low-temperature plasma device under an argon atmosphere for 45 seconds. After completion, the woven fabric is taken out and placed in a sealable immersion container 1;

[0083] The power of the plasma treatment is 55W, the argon flow rate is 150sccm, and the vacuum degree of the chamber is maintained at ≤100Pa during the treatment;

[0084] S2. Evacuate the immersion container 1 to -0.08 MPa, then add silica sol, soak the woven fabric under vacuum conditions for 60 minutes, take it out and immediately put it into the autoclave, seal the autoclave, heat the autoclave to 37°C at 4°C / min, inject liquid CO2, and increase the pressure to 12 MPa at a rate of 1.5 MPa / min. Maintain this temperature and pressure condition for 1.5 hours. After the treatment is completed, release the pressure at a rate of 0.3 MPa / min, and take it out after it is released to normal pressure.

[0085] The silica sol preparation method comprises the following steps: adding 7% of mesoporous silica nanoparticles to a base silica sol, uniformly dispersing the particles by ultrasonication, dripping a ZIF-8 methanol solution (molar concentration of 0.1 mol / L) at 4.5% by mass of the base silica sol, continuously stirring at 200 r / min for 1.5 hours, then adding a PNIPAM aqueous solution (mass fraction of 11%) at 2.7% by mass of the base silica sol, stirring and mixing, adjusting the pH to 4.5 with hydrochloric acid, heating to 50° C., reacting for 2.5 hours, cooling to room temperature, adding benzoin dimethyl ether at 0.7% by mass of the base silica sol, stirring in the dark until the particles are completely dissolved, and finally adding Fe3O4@SiO2 particles at 1.7% by mass of the base silica sol, and uniformly dispersing the particles by ultrasonication.

[0086] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0087] S4. After the stitching is completed, the preform and the mold are placed in an oven and baked at 120° C. for 5 hours. After the preform is cooled to room temperature, it is demoulded to obtain a rough radome blank;

[0088] S5. Grind and polish the rough antenna cover.

[0089] Comparative Example 4

[0090] A method for rapidly prototyping a needle-stitched quartz composite ceramic radome comprises the following steps:

[0091] S1. The woven fabric is ultrasonically cleaned in anhydrous ethanol for 12 minutes, dried, and then placed in a low-temperature plasma device under an argon atmosphere for 45 seconds. After completion, the woven fabric is taken out and placed in a sealable immersion container 1;

[0092] The power of the plasma treatment is 55W, the argon flow rate is 150sccm, and the vacuum degree of the chamber is maintained at ≤100Pa during the treatment;

[0093] S2. Evacuate the immersion container 1 to -0.08 MPa, then add silica sol, soak the woven fabric under vacuum conditions for 60 minutes, take it out and immediately put it into the autoclave, seal the autoclave, heat the autoclave to 37°C at 4°C / min, inject liquid CO2, and increase the pressure to 12 MPa at a rate of 1.5 MPa / min. Maintain this temperature and pressure condition for 1.5 hours. After the treatment is completed, release the pressure at a rate of 0.3 MPa / min, and take it out after it is released to normal pressure.

[0094] The silica sol is a base silica sol;

[0095] S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform;

[0096] S4. After the stitching is completed, the preform and the mold are placed in an oven, and the temperature is first raised to 35°C at 3.5°C / min, maintained for 1.5 hours, and then further raised to 120°C and maintained for 4.5 hours. After completion, the preform is cooled to room temperature and demolded to obtain the radome blank;

[0097] S5. Grind and polish the rough antenna cover.

[0098] Performance Testing

[0099] Radomes were prepared using the methods of Examples 1 to 3 and Comparative Examples 1 to 3, respectively, and then subjected to mechanical property tests. The test results are shown in Table 1 below.

[0100] Table 1

[0101] Grouping Compression strength (MPa) Interlaminar shear strength (MPa) Ablation rate (mm / min) Example 1 158±5 14±2 0.12±0.02 Example 2 160±6 14±2 0.10±0.01 Example 3 159±6 14±2 0.11±0.01 Comparative Example 1 153±5 13±1 0.16±0.04 Comparative Example 2 150±4 12±2 0.19±0.05 Comparative Example 3 155±5 12±2 0.23±0.02 Comparative Example 4 140±4 12±1 0.21±0.06

[0102] As can be seen from Table 1 above, the compressive strength and interlaminar shear strength of the antenna covers of Examples 1 to 3 are better than those of the comparative example, indicating that the antenna cover of the present invention has excellent mechanical properties, and the ablation rate is only (0.10±0.01)~(0.12±0.02) mm / min, which has good ablation resistance.

[0103] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A method for rapid prototyping of a needle-stitched quartz composite ceramic radome, characterized in that: The steps include: S1. After pre-treating the woven fabric, place it in a sealable soaking container; S2. Evacuate the immersion container, add silica sol, and soak the woven fabric under vacuum conditions. After completion, take it out and immediately place it in a supercritical CO2 environment for 1 to 2 hours; S3, taking out the woven fabric and sewing it by needle punching according to the shape of the mask to obtain a preform; S4. After the stitching is completed, the preform and the mold are placed in an oven for heat curing. After the preform is cooled to room temperature, it is demoulded to obtain a rough radome blank. S5. Perform precision machining on the radome rough blank.

2. The method for rapid prototyping of a needle-stitched quartz composite ceramic antenna cover according to claim 1, characterized in that: The braided fabric in step S1 is one of a quartz antenna cover multi-layer cloth cover, a quartz fiber cloth, and a quartz felt.

3. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The pretreatment method described in step S1 is: the woven fabric is ultrasonically cleaned in anhydrous ethanol for 10 to 15 minutes, dried, and then placed in a low-temperature plasma device for treatment under an argon atmosphere for 30 to 60 seconds. After completion, it is taken out for use.

4. The method for rapid prototyping of a needle-stitched quartz composite ceramic antenna cover according to claim 3, characterized in that: The power of the plasma treatment described in step (1) is 50~60W, the argon gas flow rate is 100~200sccm, and the vacuum degree of the chamber is maintained at ≤100Pa during the treatment process.

5. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The preparation method of the silica sol described in step S2 is as follows: 6~8% of mesoporous silica nanoparticles are added to the basic silica sol, and after ultrasonic dispersion, 4~5% of the weight of the basic silica sol ZIF-8 methanol solution is added dropwise, and stirring is continued at 150~250r / min for 1~2h, and then 2.5~3% of the weight of the basic silica sol PNIPAM aqueous solution is added. After stirring and mixing, the pH is adjusted to 4~5 with hydrochloric acid, the temperature is raised to 50°C, and the reaction is carried out for 2~3h. Then, the mixture is cooled to room temperature, 0.6~0.8% of the weight of the basic silica sol photoinitiator is added, and the mixture is stirred in the dark until completely dissolved. Finally, 1.5~2% of the weight of the basic silica sol Fe3O4@SiO2 particles are added and ultrasonic dispersion is performed.

6. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The molar concentration of the ZIF-8 methanol solution is 0.1 mol / L; The mass fraction of PNIPAM aqueous solution is 10~12%; The photoinitiator is benzoin dimethyl ether.

7. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The vacuum condition described in step S2 is -0.07 to -0.095 MPa, and the soaking time is 30 to 90 minutes.

8. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The step S2 of placing the woven fabric in a supercritical CO2 environment for 1 to 2 hours is as follows: placing the woven fabric soaked in silica sol into an autoclave, sealing the autoclave, heating the autoclave to 35 to 40°C at a rate of 3 to 5°C / min, injecting liquid CO2, and increasing the pressure to 10 to 15 MPa at a rate of 1 to 2 MPa / min. Maintaining the pressure under these temperature and pressure conditions for 1 to 2 hours, after the treatment is completed, releasing the pressure at a rate of 0.2 to 0.5 MPa / min, and taking it out after releasing it to normal pressure.

9. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The heat curing treatment in step S4 is as follows: placing the preform and the mold together in an oven, first heating to 35°C at a rate of 3-4°C / min, maintaining for 1-2 hours, then continuing to heat to 120°C, and maintaining for 4-5 hours.

10. The method for rapid prototyping of a needle-stitched quartz composite ceramic radome according to claim 1, characterized in that: The precision machining in step S5 is grinding and polishing.

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