A thin-walled cylindrical component made of quartz fiber and silicone resin composite material and its preparation method

Abstract

This invention relates to the field of aerospace technology, and discloses a thin-walled cylindrical component made of quartz fiber and silicone resin composite material and its preparation method. The preparation method includes: preparing a quartz fiber and silicone resin composite material according to a specified ratio, degassing and setting aside; installing quartz fiber preforms of different densities in a test mold; sequentially performing mold closing, sealing, airtightness testing, RTM injection molding, curing, and demolding to obtain quartz fiber and silicone resin composite material specimens of different densities; testing their performance to obtain quartz fiber and silicone resin composite material specimens that meet the requirements; determining the density of the target quartz fiber preform; preparing the target quartz fiber preform based on this density; and obtaining the thin-walled cylindrical component of the quartz fiber and silicone resin composite material through the same subsequent processes. This method solves the problems of molding processes being unable to prepare thin-walled cylindrical specimens and the high cost of winding processes, and has been applied in the combustion chamber of ramjet engines.

Description

Technical Field

[0001] This invention relates to the field of aerospace technology, and in particular to a thin-walled cylindrical component made of quartz fiber and silicone resin composite material and its preparation method. Background Technology

[0002] Currently, the aerospace field is developing rapidly, with ramjet engine upgrade cycles becoming shorter and cost control increasingly stringent. Ramjet engine afterburners operate in an oxygen-rich environment for extended periods, up to 600 seconds. Therefore, the thermal protection system for the afterburner must provide appropriate conditions based on different thermal, structural, and chemical environments. Simultaneously, the insulation materials used in ramjet engines require extremely high resistance to high-temperature ablation, but these materials are not yet adapted to the rapid upgrade speed and cost control requirements of ramjet engines, particularly the high-temperature ablation resistance requirements of the afterburner, which directly impact the ramjet engine's ability to maintain its intended flight attitude and trajectory. To meet the high-temperature erosion resistance requirements of the ramjet engine afterburner, it is necessary to improve manufacturing efficiency and reduce material costs.

[0003] Composite materials are a new type of material characterized by high specific strength, specific modulus, low density, and customizable design, and are widely used in aerospace, automotive manufacturing, medical devices, and other fields. Composite materials mainly consist of a matrix material and a reinforcement. Matrix materials are classified into resin matrices, metal matrices, and ceramic matrices. Currently, resin-matrix composite materials are widely used in the aerospace field. Silicone resin is a special type of resin material with a Q-type or T-type branched structure, and its core and skeleton are Si-O-Si molecular chain segments. In addition to excellent flowability, low density, and insulation properties, silicone resin often also possesses high-temperature resistance and low shrinkage. It has been widely used in the manufacturing and processing of high-end materials in medical devices, automobiles, additive manufacturing, and aerospace, and its application is continuously expanding to the modification of other types of non-silicon-based polymer materials. Quartz fiber is a fibrous material composed of quartz. Compared with commonly used carbon fibers, it has low thermal conductivity, high elongation at break, and good flexibility. Therefore, quartz fiber has wide applications in the field of thermal insulation.

[0004] Silicone resin as the continuous phase and quartz fiber as the reinforcing material are composite materials used in the aerospace field as special materials resistant to high-temperature ablation. Currently, silicone resin / quartz fiber composites are often produced using compression molding, which can lead to defects such as insufficient resin and porosity, resulting in significant reductions in mechanical properties, ablation resistance, and stability. Furthermore, compression molding is costly. On the other hand, winding is often used to prepare thin-walled cylindrical specimens, but this process requires expensive equipment. Therefore, porosity, insufficient resin, and high cost of silicone resin / carbon fiber composites remain pressing issues that need to be addressed, requiring solutions to product defects and molding challenges through process improvements. Summary of the Invention

[0005] Based on the above, the purpose of this invention is to provide a thin-walled cylindrical part of quartz fiber silicone resin composite material and its preparation method, which solves the problems that molding process cannot prepare thin-walled cylindrical specimens and winding process is costly, and can be applied in the combustion chamber of ramjet engine.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A method for preparing a thin-walled cylindrical component made of quartz fiber and silicone resin composite material includes the following steps:

[0008] According to the formula, add silicone resin component A and silicone resin component B to the container and stir evenly; add inhibitor and mix evenly; finally add catalyst and mix evenly to obtain quartz fiber silicone resin composite material.

[0009] The quartz fiber silicone resin composite material is defoamed until no bubbles are generated on its surface;

[0010] Quartz fiber preforms of different densities were installed in test molds for mold closing, sealing, and airtightness testing.

[0011] The quartz fiber silicone resin composite material was vacuum-injected into the test mold using the RTM process and then cured by heating.

[0012] The test mold after glue injection was demolded to obtain quartz fiber silicone resin composite material specimens of different densities;

[0013] The performance of quartz fiber silicone resin composite material specimens with different densities was tested to obtain quartz fiber silicone resin composite material specimens that meet the requirements, and the density of the target quartz fiber preform was determined.

[0014] The target quartz fiber preform is installed in a thin-walled cylindrical mold, and mold closing, sealing and airtightness testing are performed.

[0015] The quartz fiber silicone resin composite material is vacuum-injected into the thin-walled cylindrical mold using the RTM process and then cured by heating.

[0016] After the thin-walled cylindrical mold is injected with adhesive, a demolding process is performed to obtain a thin-walled cylindrical part made of quartz fiber silicone resin composite material.

[0017] A preferred embodiment of a method for preparing a thin-walled cylindrical component made of quartz fiber silicone resin composite material includes the following components in parts by weight:

[0018] 60 parts of silicone resin component A

[0019] 40-45 parts of silicone resin component B

[0020] Inhibitor 0.08-0.12 parts

[0021] Catalyst 0.04-0.08 parts;

[0022] The silicone resin component A includes vinyl-terminated polydimethylsiloxane;

[0023] The silicone resin component B includes vinyl-terminated polydimethylsiloxane and linear methylhydropolysiloxane.

[0024] In a preferred embodiment of a method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material, the silicone resin component B is SH-VMQ silicone resin, specifically 5202N silicone oil type resin, with a resin content of 50%, a viscosity of 30,000 to 100,000 cP, an ethyl content of 0.5 to 1.5%, and an MQ ratio of 0.6 to 0.9.

[0025] In a preferred embodiment of a method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material, the inhibitor comprises an alkynyl alcohol compound; and the catalyst comprises a platinum-vinylsilane complex.

[0026] In a preferred embodiment of a method for preparing a thin-walled cylindrical component of quartz fiber-silicone resin composite material, the density of the target quartz fiber preform is 0.25 g / cm³. 3 -0.35g / cm 3 .

[0027] In a preferred embodiment of a method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material, the vacuum degree during the airtightness test is -0.70 bar to -1.0 bar.

[0028] In a preferred embodiment of a method for preparing a thin-walled cylindrical part of quartz fiber silicone resin composite material, the vacuum degree during vacuum injection is -0.70 bar to -1.0 bar.

[0029] In a preferred embodiment of a method for preparing a thin-walled cylindrical part of quartz fiber silicone resin composite material, the curing temperature is 120-160℃ and the curing time is 4-12h.

[0030] A thin-walled cylindrical component made of quartz fiber and silicone resin composite material is prepared by any of the above-described preparation methods.

[0031] An application of a thin-walled cylindrical component made of quartz fiber and silicone resin composite material, wherein the thin-walled cylindrical component made of quartz fiber and silicone resin composite material is used in the combustion chamber of a stamping engine.

[0032] The beneficial effects of this invention are as follows:

[0033] This invention provides a thin-walled cylindrical component made of quartz fiber and silicone resin composite material and its preparation method. The quartz fiber and silicone resin composite material is prepared using a vacuum-assisted RTM process, which significantly reduces porosity in the specimen and solves defects such as insufficient adhesive. It also addresses the limitations of molding processes in preparing thin-walled cylindrical specimens and the high cost of winding processes. Furthermore, it significantly enhances the material's mechanical properties, ablation resistance, and stability, while reducing production costs, making it suitable for use in the combustion chambers of ramjet engines. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0035] Figure 1 Flowchart of the preparation process of the thin-walled cylindrical part of quartz fiber silicone resin composite material of the present invention;

[0036] Figure 2 This is an image showing the apparent quality of the thin-walled cylindrical component made of quartz fiber and silicone resin composite material prepared in Example 1 of this invention.

[0037] Figure 3 This is an image showing the surface quality of the thin-walled cylindrical component made of quartz fiber and silicone resin composite material prepared in Example 2 of this invention.

[0038] Figure 4 This is an image showing the apparent quality of the thin-walled cylindrical part made of quartz fiber silicone resin composite material prepared in Comparative Example 1 of this invention. Detailed Implementation

[0039] To facilitate understanding of the present invention, a more comprehensive description will be provided below. The present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention. Unless otherwise defined, all technical and scientific terms used in this invention pertain to the technical field of the invention.

[0040] This embodiment provides a method for preparing a thin-walled cylindrical component made of quartz fiber and silicone resin composite material, including the following steps:

[0041] S100: According to the formula, add silicone resin component A and silicone resin component B to the container and stir evenly; add inhibitor and mix evenly; finally add catalyst and mix evenly to obtain quartz fiber silicone resin composite material.

[0042] Specifically, the quartz fiber silicone resin composite material comprises the following components in parts by weight: 60 parts silicone resin component A, 40-45 parts silicone resin component B, 0.08-0.12 parts inhibitor, and 0.04-0.08 parts catalyst; wherein silicone resin component A includes vinyl-terminated polydimethylsiloxane; silicone resin component B includes vinyl-terminated polydimethylsiloxane and linear methylhydrogen polysiloxane, with linear methylhydrogen polysiloxane serving as a crosslinking agent; silicone resin component B is SH-VMQ silicone resin, specifically 5202N silicone oil type resin, with a resin content of 50%, a viscosity of 30,000-100,000 cP, an ethyl content of 0.5-1.5%, and an MQ ratio of 0.6-0.9.

[0043] S200: Defoaming treatment of quartz fiber silicone resin composite material until no bubbles are generated on its surface;

[0044] Specifically, the degassing process uses an oil-free vacuum pump to degas the quartz fiber silicone resin composite material until no bubbles are generated on the surface of the quartz fiber silicone resin composite material.

[0045] S300: Quartz fiber preforms of different densities are installed in a test mold for mold closing, sealing and airtightness testing;

[0046] Specifically, in this embodiment, quartz felt of different densities is used to prepare fiber preforms of different densities, each with a size of 150mm×150mm×10mm. The fiber preforms are installed in a mold, which consists of an upper mold, a middle mold, and a lower mold. The glue inlet and glue outlet are both located on the middle mold. The glue inlet is connected to the glue inlet pipe via a manual ball valve. The mold is locked in place using screws and nuts. The glue inlet ball valve is closed, and the glue outlet is connected to the vacuum pump using a pneumatic hose. The glue outlet ball valve is opened, and then the vacuum pump is started. The vacuum level is set to -0.70 bar to -1.0 bar. When the vacuum level reaches -1.0 bar, the vacuum pump stops working and a timer begins. If the vacuum pump does not work within 20 minutes (the vacuum level is maintained between -0.70 bar and -1.0 bar), it indicates that the mold has good airtightness and the next process can proceed.

[0047] S400: Using RTM process, quartz fiber silicone resin composite material is vacuum-injected into a test mold and then cured by heating;

[0048] Specifically, an injection test is conducted using a pressure tank. Pneumatic hoses are used to connect the pressure tank and the test mold, as well as the air source. All ball valves on the test mold are opened, and the pressure is adjusted to 0.15 MPa for injection. When adhesive overflows from the test mold's outlet, the corresponding ball valve is closed until all outlets overflow. Next, pressure holding and degassing are performed. When adhesive overflows from two outlets, all outlet ball valves are closed, and the injection pressure is maintained for 10-20 minutes. Then, one outlet ball valve is opened to degas until no more bubbles are expelled, and the valve with no bubbles is closed. The same operation is performed on the other outlet ball valve. After degassing, all outlet ball valves are closed, and pressure holding is performed for 10-20 minutes. Degassing is then performed again. After two rounds of pressure holding and degassing, all ball valves are closed, all pipes are disassembled, and the test mold is placed stably in an oven for heat curing. The curing temperature is 120-160℃, and the curing time is 4-12 hours. The curing temperature can be set to 120℃, 140℃, or 160℃, and the curing time is 4 to 12 hours, which can be set to 4 hours, 8 hours, or 12 hours.

[0049] S500: Demolding treatment is performed on the test mold after glue injection to obtain quartz fiber silicone resin composite material specimens of different densities;

[0050] Specifically, the demolding process involves removing the connecting bolts on the test mold and using the reverse screw holes for demolding to obtain a quartz fiber silicone resin composite material specimen.

[0051] S600: Test the performance of quartz fiber silicone resin composite specimens with different densities, obtain quartz fiber silicone resin composite specimens that meet the requirements, and determine the density of the target quartz fiber preform.

[0052] Specifically, the hardness of the test plates was collected using a Shore D hardness tester; then, a CNC machine tool was used to process the quartz fiber silicone resin composite specimens into mechanical specimens and oxyacetylene ablation specimens, and the mechanical properties of the mechanical specimens and the oxyacetylene ablation properties of the oxyacetylene specimens were tested. The goal was to find quartz fiber silicone resin composite specimens that simultaneously possessed excellent mechanical properties and ablation resistance, thereby determining the density of the target quartz fiber preform.

[0053] Specifically, when directly measuring the oxyacetylene ablation performance of thin-walled cylindrical specimens, the cylindrical specimens require a maximum diameter of 30 mm and a maximum thickness of 10 mm. Therefore, the thin-walled cylindrical specimens prepared in this application (inner diameter 116.5 mm, thickness 4.0 mm) do not meet the requirements for measuring the oxyacetylene ablation performance. It is necessary to first prepare quartz fiber silicone resin composite specimens to measure the relevant properties, determine the density of the target quartz fiber preform, and then use the target quartz fiber preform of the density to prepare the quartz fiber silicone resin composite thin-walled cylindrical specimens.

[0054] S700: Install the target quartz fiber preform in a thin-walled cylindrical mold, and perform mold closing, sealing and airtightness testing;

[0055] Specifically, the quartz felt is prepared according to the density of the target quartz fiber preform, with an inner diameter of 116.5 mm, a thickness of 4.0 mm, and a length of 120 mm. The fiber preform is then mounted on a mandrel. The mold consists of four parts: an upper mold, a mandrel, a lower left mold, and a lower right mold. The glue inlet and outlet are both located on the upper mold. The glue inlet is connected to the glue inlet pipe via a manual ball valve. The mold is locked with screws and nuts, and the glue inlet ball valve is closed. The glue outlet is connected to the vacuum pump using a pneumatic hose, and the glue outlet ball valve is opened. Then, the vacuum pump is started, and the vacuum degree is set to -0.70 bar to -1.0 bar. When the vacuum degree reaches -1.0 bar, the vacuum pump stops working and a timer begins. If the vacuum pump does not work within 10 to 20 minutes (the vacuum degree is maintained at -0.70 bar to -1.0 bar), it indicates that the mold has good airtightness and the next process can proceed.

[0056] S800: Using RTM process, quartz fiber silicone resin composite material is vacuum-injected into a thin-walled cylindrical mold and then cured by heating;

[0057] Specifically, an injection test was conducted using a pressure tank. Pneumatic hoses were connected to the pressure tank and the thin-walled cylindrical mold, as well as the air source. All ball valves on the thin-walled cylindrical mold were opened, and the pressure was adjusted to 0.15 MPa for injection. When adhesive overflowed from the outlet of the thin-walled cylindrical mold, the corresponding ball valve was closed until all outlets overflowed. Next, pressure holding and degassing were performed. When adhesive overflowed from two outlets, all outlet ball valves were closed, and the injection pressure was maintained for 10-20 minutes. Then, one outlet ball valve was opened to degas until no more bubbles were expelled, and the valve with no bubbles was closed. The same operation was performed on the other outlet ball valve. After degassing, all outlet ball valves were closed, and pressure holding was performed for 10-20 minutes. Degassing was then performed again. After two rounds of pressure holding and degassing, all ball valves were closed, all pipes were disassembled, and the thin-walled cylindrical mold was placed stably in an oven for heating and curing. The curing temperature was 120-160℃, and the curing time was 4-12 hours. The curing temperature can be set to 120℃, 140℃, or 160℃, and the curing time is 4 to 12 hours, which can be set to 4 hours, 8 hours, or 12 hours.

[0058] S900: Demolding process is performed on the thin-walled cylindrical mold after glue injection to obtain a thin-walled cylindrical part of quartz fiber silicone resin composite material.

[0059] Specifically, the demolding process involves removing the connecting bolts on the thin-walled cylindrical mold and using the reverse screw hole for demolding to obtain a thin-walled cylindrical part made of quartz fiber silicone resin composite material.

[0060] The present invention will be further described below through specific embodiments.

[0061] Example 1

[0062] Specimen 1: The components of a quartz fiber silicone resin composite specimen include:

[0063] 60 parts silicone resin component A, 42 parts silicone resin component B, 0.1 parts inhibitor, and 0.06 parts catalyst;

[0064] Component A of the silicone resin is vinyl-terminated silicone resin, and component B is a combination of vinyl-terminated silicone resin and linear methylhydropolysiloxane. The inhibitor is an alkynyl alcohol compound, and the catalyst is a platinum-vinylsilane complex. The density of the quartz fiber silicone resin composite specimen is 0.3 g / cm³. 3 .

[0065] A method for preparing quartz fiber silicone resin composite specimens:

[0066] Ingredients: Ingredients are prepared according to the formula requirements. First, add 180g of silicone resin component A and 126g of silicone resin component B to the container and use a disperser to stir until the adhesive is mixed evenly. Then, add 0.3g of inhibitor and use a disperser to mix the adhesive evenly. Finally, add 0.18g of catalyst and use a disperser to mix the adhesive evenly to obtain quartz fiber silicone resin composite material.

[0067] Degassing: Use an oil-free vacuum pump to degas the quartz fiber silicone resin composite material until no bubbles are generated on the surface of the quartz fiber silicone resin composite material.

[0068] Mold assembly and airtightness testing: The quartz felt was prepared according to a density of 0.3 g / cm³. 3 A fiber preform with dimensions of 150mm × 150mm × 10mm is prepared and installed in a mold consisting of an upper mold, a middle mold, and a lower mold. The glue inlet and outlet are both located on the middle mold. The glue inlet is connected to the glue inlet pipe via a manual ball valve. The mold is then locked in place using screws and nuts. The glue inlet ball valve is closed, and the glue outlet is connected to a vacuum pump using a pneumatic hose. The glue outlet ball valve is opened, and the vacuum pump is started. The vacuum level is set to -0.70 bar to -1.0 bar. When the vacuum level reaches -1.0 bar, the vacuum pump stops working and a timer begins. If the vacuum pump does not work within 20 minutes (the vacuum level remains between -0.70 bar and -1.0 bar), it indicates that the mold has good airtightness and the next process can proceed.

[0069] Injection: Conduct injection tests using a pressure tank. Connect the pressure tank and mold, and the pressure tank and air source using a pneumatic hose. Open all ball valves on the mold and adjust the pressure to 0.15 MPa to inject the adhesive. When adhesive overflows from the mold outlet, close the corresponding ball valve until adhesive overflows from all outlets.

[0070] Pressure holding and degassing: When glue overflows from both outlets, close all outlet ball valves and maintain injection pressure for 10-20 minutes. Then, open one outlet ball valve to degas until no more bubbles are released, and close the valve where no bubbles are released. Repeat the same operation for the other outlet ball valve. After degassing, close all outlet ball valves and maintain pressure for 10-20 minutes, then degas again. After two rounds of pressure holding and degassing, close all ball valves, disassemble all pipes, and gently place the mold into the oven for heating and curing.

[0071] Curing: The curing temperature is 120-160℃, and the curing time is 4-12 hours.

[0072] Demolding: Remove the connecting bolts on the mold and demold using the reverse screw holes to obtain the quartz fiber silicone resin composite material specimen.

[0073] Specimen 2: The preparation method of the quartz fiber silicone resin composite specimen is the same as that of specimen 1, but the density of the quartz felt is 0.4 g / cm³. 3 .

[0074] Specimen 3: The preparation method of the quartz fiber silicone resin composite specimen is the same as that of specimen 1, but the density of the quartz felt is 0.5 g / cm³. 3 .

[0075] Specimen 4: The preparation method of the quartz fiber silicone resin composite specimen is the same as that of specimen 1, but the density of the quartz felt is 0.6 g / cm³. 3 .

[0076] The hardness of the silica fiber silicone resin composite specimens prepared by specimens 1-4 was collected using a Shore D hardness tester. Then, the silica fiber silicone resin composite specimens were processed into mechanical specimens and oxyacetylene ablation specimens using a CNC machine tool. The mechanical properties of the mechanical specimens (GB / T528) and the oxyacetylene ablation properties of the oxyacetylene specimens (GJB323A) were tested. The results of the mechanical property test and the oxyacetylene property test are shown in Tables 1 and 2, respectively.

[0077] Table 1. Results of Mechanical Property Testing of Quartz Fiber Silicone Resin Composite Specimens

[0078]

[0079] Table 2. Oxyacetylene ablation performance parameters of quartz fiber-silicone composite specimens

[0080]

[0081]

[0082] Tables 1 and 2 show that with increasing density of quartz felt, tensile strength first increases and then decreases, while elongation at break generally increases. Simultaneously, with increasing density of quartz felt, the material density gradually increases, and the linear ablation rate gradually increases. When the density of quartz felt is too low, the specimen strength is low. Therefore, when the density of quartz felt is 0.3 g / cm³... 3 Density error ±0.05 g / cm³ 3 The density is specifically 0.25 g / cm³. 3 -0.35g / cm 3 The prepared quartz fiber-silicone resin composite material specimens have the highest density and the lowest linear ablation rate, exhibiting the best ablation resistance and excellent mechanical properties. They are used to prepare thin-walled cylindrical parts made of quartz fiber-silicone resin composite materials, meeting the application requirements in the combustion chamber of ramjet engines.

[0083] A method for preparing a thin-walled cylindrical component made of quartz fiber and silicone resin composite material:

[0084] The composition is the same as that of the quartz fiber silicone resin composite material specimen 1, but the preparation process conditions are different. The main purpose is to prepare a thin-walled cylindrical part of quartz fiber silicone resin composite material.

[0085] Ingredients: Ingredients are prepared according to the formula requirements. First, add 360g of silicone resin component A and 252g of silicone resin component B to the container and use a disperser to stir until the adhesive is mixed evenly. Then, add 0.6g of inhibitor and use a disperser to mix the adhesive evenly. Finally, add 0.36g of catalyst and use a disperser to mix the adhesive evenly to obtain quartz fiber silicone resin composite material.

[0086] Degassing: Use an oil-free vacuum pump to degas the quartz fiber silicone resin composite material until no bubbles are generated on the surface of the quartz fiber silicone resin composite material;

[0087] Mold assembly and airtightness testing: The quartz felt was prepared according to a density of 0.3 g / cm³. 3A fiber preform with an inner diameter of 116.5 mm, a thickness of 4.0 mm, and a length of 120 mm is prepared. The fiber preform is then fitted onto a mandrel. The mold consists of four parts: an upper mold, a mandrel, a lower left mold, and a lower right mold. Both the glue inlet and outlet are located on the upper mold. The glue inlet is connected to the glue inlet pipe via a manual ball valve. The mold is locked in place using screws and nuts. The glue inlet ball valve is closed. The glue outlet is connected to a vacuum pump using a pneumatic hose. The glue outlet ball valve is opened, and then the vacuum pump is started. The vacuum level is set to -0.70 bar to -1.0 bar. When the vacuum level reaches -1.0 bar, the vacuum pump stops working and a timer begins. If the vacuum pump does not work within 10 to 20 minutes (the vacuum level is maintained at -0.70 bar to -1.0 bar), it indicates that the mold has good airtightness and the next process can proceed.

[0088] Injection: Conduct injection tests using a pressure tank. Connect the pressure tank and mold using pneumatic hoses, connecting the pressure tank to the air source, and the mold to the vacuum pump. Open all ball valves on the mold and adjust the pressure to 0.15 MPa. Inject the adhesive, maintaining the vacuum level inside the mold cavity between -0.70 bar and -1.0 bar. When adhesive overflows from the mold outlets, close the corresponding ball valve and remove the vacuum assist until adhesive overflows from all outlets.

[0089] Pressure holding and degassing: When glue overflows from both outlets, close all outlet ball valves and maintain injection pressure for 15 minutes. Then, open one outlet ball valve to degas until no more bubbles are released, and close the valve where no bubbles are released. Repeat the same operation for the other outlet ball valve. After degassing, close all outlet ball valves and maintain pressure for 15 minutes, then degas again. After two rounds of pressure holding and degassing, close all ball valves, disassemble all pipes, and gently place the mold into the oven for heating and curing.

[0090] Curing: The curing temperature is 150℃, and the curing time is 6 hours;

[0091] Demolding: Remove the connecting bolts on the mold and demold using the reverse screw hole to obtain a thin-walled cylindrical part of quartz fiber silicone resin composite material.

[0092] Example 2

[0093] A method for preparing a thin-walled cylindrical component made of quartz fiber and silicone resin composite material:

[0094] The testing procedure was the same as in Example 1, using specimens with a density of 0.3 g / cm³. 3 The quartz felt is prepared using the same process as the thin-walled cylindrical part of quartz fiber silicone resin composite material prepared in Example 1, but the raw material composition is different from that of the specimen prepared in Example 1.

[0095] The components of a quartz fiber silicone resin composite specimen include:

[0096] 60 parts silicone resin component A, 40 parts silicone resin component B, 0.08 parts inhibitor, and 0.08 parts catalyst;

[0097] The preparation of quartz fiber silicone resin composite material involves: first, adding 360g of silicone resin component A and 240g of silicone resin component B to a container, and stirring with a disperser to ensure uniform mixing; then, adding 0.48g of inhibitor and stirring with a disperser to ensure uniform mixing; finally, adding 0.48g of catalyst and stirring with a disperser to ensure uniform mixing, thus obtaining the quartz fiber silicone resin composite material.

[0098] Example 3

[0099] A method for preparing a thin-walled cylindrical component made of quartz fiber and silicone resin composite material:

[0100] The testing procedure was the same as in Example 1, using specimens with a density of 0.3 g / cm³. 3 The quartz felt is prepared using the same process as the thin-walled cylindrical part of quartz fiber silicone resin composite material prepared in Example 1, but the raw material composition is different from that of the specimen prepared in Example 1.

[0101] The components of a quartz fiber silicone resin composite specimen include:

[0102] 60 parts silicone resin component A, 45 parts silicone resin component B, 0.12 parts inhibitor, and 0.04 parts catalyst;

[0103] The preparation of quartz fiber silicone resin composite material involves: first, adding 360g of silicone resin component A and 270g of silicone resin component B to a container, and stirring with a disperser to ensure uniform mixing; then, adding 0.72g of inhibitor and stirring with a disperser to ensure uniform mixing; finally, adding 0.24g of catalyst and stirring with a disperser to ensure uniform mixing, thus obtaining the quartz fiber silicone resin composite material.

[0104] To further illustrate the key aspects of this patent, comparative examples are included.

[0105] Comparative Example 1

[0106] The preparation process and raw material composition were consistent with those in Example 1. During the preparation of the thin-walled cylindrical part of quartz fiber silicone resin composite material, the mold cavity was connected to the atmosphere during the glue injection process and was not carried out in a vacuum environment.

[0107] The apparent quality of the thin-walled cylindrical specimens made of quartz fiber-silicone resin composite material prepared in Examples 1-3 and Comparative Example 1 was collected using a digital camera. The apparent quality of the thin-walled cylindrical specimens prepared in the examples is as follows: Figure 2 and Figure 3As shown, the apparent quality of the thin-walled cylindrical part prepared in Comparative Example 1 is as follows: Figure 4 As shown in the figure, Figure 2 and Figure 3 The surface of the thin-walled cylindrical part is smooth and clean, with no defects such as missing glue. Figure 3 The surface of the thin-walled cylindrical part exhibits dry spots and insufficient glue, which may be caused by air trapping. Therefore, a vacuum environment needs to be provided within the mold cavity (during the injection process) to prevent insufficient glue defects from forming in the sample.

[0108] The thin-walled cylindrical part of quartz fiber silicone resin composite material prepared in Example 1 was machined into the required dimensions using a CNC machine tool.

[0109] After processing, the specimens were inspected using vernier calipers to measure their length, inner diameter, thickness, and step dimensions. Specifically, the length was measured at four points evenly distributed along the circumference in all four quadrants; the inner diameter was measured at four points at each of the two openings (evenly distributed across the four quadrants); the thickness was measured at the same points as the inner diameter (a total of eight points); the step height was measured at four points evenly distributed along the circumference in all four quadrants; and the outer diameter of the step was measured at the same points as the step height (a total of four points). The specific design requirements for the specimen dimensions and test values ​​are shown in Table 3. All measurements conformed to the standards.

[0110] Table 3. Dimensional Data of Thin-Walled Cylindrical Parts Made of Quartz Fiber and Silicone Resin Composite Materials

[0111]

[0112]

[0113] The above description is merely a preferred embodiment of the present invention and the technical principles employed. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions can be made without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. More other equivalent embodiments may be included without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for preparing a thin-walled cylindrical component made of quartz fiber and silicone resin composite material, characterized in that, Includes the following steps: According to the formula, add silicone resin component A and silicone resin component B to the container and stir evenly; add inhibitor and mix evenly; finally add catalyst and mix evenly to obtain quartz fiber silicone resin composite material. The quartz fiber silicone resin composite material is defoamed until no bubbles are generated on its surface; Quartz fiber preforms of different densities were installed in test molds for mold closing, sealing, and airtightness testing. The quartz fiber silicone resin composite material was vacuum-injected into the test mold using the RTM process and then cured by heating. The test mold after glue injection was demolded to obtain quartz fiber silicone resin composite material specimens of different densities; The performance of quartz fiber silicone resin composite material specimens with different densities was tested to obtain quartz fiber silicone resin composite material specimens that meet the requirements, and the density of the target quartz fiber preform was determined. The target quartz fiber preform is installed in a thin-walled cylindrical mold, and mold closing, sealing and airtightness testing are performed. The quartz fiber silicone resin composite material is vacuum-injected into the thin-walled cylindrical mold using the RTM process and then cured by heating. After the thin-walled cylindrical mold is injected with adhesive, a demolding process is performed to obtain a thin-walled cylindrical part made of quartz fiber silicone resin composite material.

2. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 1, characterized in that, The quartz fiber silicone resin composite material comprises the following components in parts by weight: 60 parts of silicone resin component A The silicone resin component A includes vinyl-terminated polydimethylsiloxane; The silicone resin component B includes vinyl-terminated polydimethylsiloxane and linear methylhydropolysiloxane.

3. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 2, characterized in that, The silicone resin component B is SH-VMQ silicone resin, specifically 5202N silicone oil type resin, with a resin content of 50%, a viscosity of 30,000 to 100,000 cP, an ethyl content of 0.5 to 1.5%, and an MQ ratio of 0.6 to 0.

9.

4. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 1, characterized in that, The inhibitors include alkynols; the catalysts include platinum-vinylsilane complexes.

5. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 1, characterized in that, The density of the target quartz fiber preform is 0.25 g / cm³. 3 -0.35g / cm 3 .

6. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 1, characterized in that, During the airtightness test, the vacuum level is -0.70 bar to -1.0 bar.

7. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 1, characterized in that, During the vacuum dispensing process, the vacuum level is -0.70 bar to -1.0 bar.

8. The method for preparing a thin-walled cylindrical component of quartz fiber silicone resin composite material according to claim 1, characterized in that, The curing temperature is 120–160℃, and the curing time is 4–12 hours.

9. A thin-walled cylindrical component made of quartz fiber and silicone resin composite material, characterized in that, It is prepared by the preparation method according to any one of claims 1-8.

10. An application of a thin-walled cylindrical component made of quartz fiber and silicone resin composite material, based on the thin-walled cylindrical component made of quartz fiber and silicone resin composite material as described in claim 9, characterized in that, The thin-walled cylindrical component made of quartz fiber and silicone resin composite material is used in the combustion chamber of a stamping engine.

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