High-density ablation-resistant rudder heat shield cup and manufacturing method thereof

Abstract

This application relates to the field of high-temperature refractory composite materials technology, and provides a high-density ablation-resistant rudder heat shield cup and its manufacturing method. The manufacturing method includes: Z-direction sewing using 2.5D quartz fabric; placing the sewn fabric into a weft-forming device, which adjusts the fiber state of the fabric and increases the fiber volume content to 50-65%; the fabric after weft-forming is first impregnated and shaped with an inorganic sol, then impregnated and cured with a phenolic solution to obtain a rudder heat shield cup blank; finally, it is machined to obtain the rudder heat shield cup. The density of the rudder heat shield cup reaches 1.6 g / cm³. 3 The above-mentioned linear ablation rate on the kerosene small engine is less than 0.1 mm / s, and the rudder heat protection cup has excellent ablation performance, making it suitable for thermal protection of the air rudder shaft of ballistic missiles.

Description

Technical Field

[0001] This application belongs to the field of high-temperature refractory composite material technology, and in particular relates to a high-density ablation-resistant heat shield cup and its manufacturing method. Background Technology

[0002] Air rudders are crucial components for controlling the flight attitude of an aircraft. During flight attitude control, the air rudders need to rotate continuously, and the stiffness and strength of the rudder shaft are important technical indicators for aircraft stability control. Ballistic reentry missiles face a high-enthalpy, high-heat-flux aerodynamic environment near the air rudder shaft, with surface temperatures exceeding 2300°C. With reentry times of approximately tens of seconds, the air rudder shaft requires heat shields for thermal protection to reduce its temperature and ensure high stiffness.

[0003] Common ablation-resistant rudder heat shield cups use triaxial orthogonal quartz fabric / phenolic resin as the material, and are manufactured using transfer molding (RTM) technology. Triaxial orthogonal fabric has fibers in all three X, Y, and Z directions. The phenolic resin composite material reinforced by this structure exhibits excellent overall mechanical and ablation properties. However, triaxial orthogonal fabric is primarily hand-woven, resulting in low efficiency, long manufacturing cycles, and high costs. The RTM composite molding process requires molds for auxiliary molding, which are generally expensive. Furthermore, the production quantity of a single rudder heat shield cup is limited by the number of molds, making it unsuitable for mass production. Summary of the Invention

[0004] The purpose of this application is to provide a high-density ablation-resistant rudder heat shield and its manufacturing method. While ensuring the ablation performance of the rudder heat shield, it aims to solve the problems of low efficiency, long preparation cycle and high price of existing rudder heat shield manufacturing methods.

[0005] To achieve the above-mentioned objectives, the technical solution adopted in this application is as follows:

[0006] This application provides a method for manufacturing a high-density, ablation-resistant heat shield cup, comprising the following steps:

[0007] S1. Z-direction stitching is performed using 2.5D quartz fabric;

[0008] S2. The fabric obtained by sewing in step S1 is placed into the shaping device, and the fabric fibers are adjusted to a straight state by the shaping device, and the fiber volume content is increased to 50-65%;

[0009] S3. Impregnate and cure the fabric with an inorganic sol;

[0010] S4. Remove the shaping device, impregnate and cure the inorganic sol-reinforced fabric with phenolic liquid to obtain the rudder heatproof cup blank;

[0011] S5. Machining the rudder heat shield blank to obtain a density ≥1.6g / cm³. 3 The rudder heatproof cup.

[0012] As one possible design, the inorganic sol in step S3 is a silica sol, aluminum sol, silica-alumina sol, or zirconium oxide sol, and the content of the inorganic sol is ≥10%.

[0013] As one possible design, the phenolic liquid in step S4 is barium phenolic, high carbon phenolic, aminophenolic, magnesium phenolic, or boron phenolic, and the phenolic liquid has a gum content of 60-80% and a residual carbon content of ≥55% in nitrogen at 800°C.

[0014] As one possible design, the specific method for Z-direction stitching in step S1 is as follows: using a sewing machine device and quartz fiber sewing thread, the fabric is sewn together, and the density of the Z-direction stitching along the warp and weft directions of the 2.5D quartz fabric is 1-3 threads / cm and 1-3 threads / cm, respectively.

[0015] As one possible design, during the inorganic sol impregnation in step S3, the shaping device and fabric are first placed into the impregnation tank and then a vacuum is drawn. When the vacuum degree is ≤-0.09Mpa, the inorganic sol is drawn into the impregnation tank until the fabric is submerged; then the pressure is increased to 0.5-2MPa and maintained for 2-5 hours.

[0016] As one possible design, during the phenolic liquid impregnation in step S4, multiple pieces of inorganic sol-reinforced fabric are first placed in the impregnation tank with the normal of the large surface of the fabric parallel to the ground. The multiple pieces of fabric are placed parallel to each other with a spacing of 5-15 mm. Then, the fabric and phenolic liquid are preheated to 60-90℃ and kept at that temperature for 1-2 hours. Then, the impregnation tank is evacuated. When the vacuum degree is ≤-0.09 MPa, the phenolic liquid is drawn into the container until it covers the fabric. The impregnation is completed by cyclic pressurization and vacuuming.

[0017] As one possible design, during the cyclic pressurization and vacuuming process, the phenolic liquid is first pressurized to 1-2 MPa and held for 1-2 hours. After the pressure holding period, the phenolic liquid is extracted from the container until the resin level is below the lower surface of the fabric. The impregnation tank is then evacuated to a vacuum degree of ≤-0.09 MPa to remove the solvent from the phenolic liquid inside the fabric until no obvious bubbles emerge from the fabric surface. After the vacuuming period, the phenolic liquid is drawn back into the impregnation tank until the liquid level covers the fabric. This pressurization and vacuuming operation is repeated 2-5 times. After the cycle is completed, the pressure is increased to 2-4 MPa and held for 4-8 hours.

[0018] As one possible design, the curing in step S3 is specifically: 50-100℃, 10-20h; 120-160℃, 4-8h; the curing in step S4 is specifically: sequentially at 1-4MPa at 90℃, 2-4h; 120℃, 2-4h; 140℃, 2-4h; 160℃, 4-8h.

[0019] As one possible design, the shaping device in step S2 includes a clamping plate, a positioning block, and a locking bolt; the edge of the clamping plate is provided with several threaded holes, which are used in conjunction with the locking bolt; the clamping plate is provided with several parallel grooves that penetrate the length or width of the clamping plate, the grooves are 0.1-0.5mm wide, 1-2mm deep, and the spacing between any adjacent grooves is 5-15mm.

[0020] When the fabric is loaded into the shaping device, the fabric and the positioning block are placed between two clamping plates. When the locking bolt is tightened, the spacing between the clamping plates is controlled by using positioning blocks of different thicknesses.

[0021] Additionally, a heat-resistant rudder cup with a density ≥1.6g / cm³ is provided. 3 The line ablation rate is <0.1 mm / s.

[0022] The beneficial effects of this invention are as follows:

[0023] 1. The patented fabric used in the preparation of the Rudder Heat Protection Cup employs a 2.5D structure with Z-direction stitching reinforcement. This fabric structure features fiber reinforcement in all three directions, resulting in a composite material with excellent overall mechanical and ablation properties. The ablation-resistant and oxidation-resistant inorganic nanoparticles introduced during the preparation of the Rudder Heat Protection Cup form an inorganic-organic hybrid interpenetrating network structure with phenolic resin. Compared to pure phenolic resin, the hybrid phenolic resin exhibits improved heat resistance, oxidation resistance, and ablation performance. The patented Rudder Heat Protection Cup achieves a density of 1.6 g / cm³. 3 The above-mentioned linear ablation rate on the kerosene small engine is less than 0.1 mm / s, and the rudder heat protection cup has excellent ablation performance, making it suitable for thermal protection of the air rudder shaft of ballistic missiles.

[0024] 2. Before impregnation, a shaping device is used to adjust the internal fiber state of the fabric, significantly increasing the fiber volume content and improving the ablation performance of the composite material. The fabric is first impregnated and cured with inorganic sol, which improves the thermal properties of the material and sets the fabric shape. This allows for direct impregnation of the fabric with phenolic liquid without the need for a shaping device, simplifying the operation and improving production efficiency. During phenolic liquid impregnation, the fabric placement is designed, and the solvent is removed by cyclic pressurization and vacuum removal, efficiently achieving the simultaneous composite molding of multiple rudder heat shield fabrics in the same furnace. This enables the batch production of rudder heat shield blanks. Compared with the RTM process, the manufacturing time for a single rudder heat shield can be reduced by more than 90%. Fabric weaving costs account for 50-70% of the cost of the rudder heat shield. Compared with triaxial orthogonal quartz fabric, the use of mechanically woven 2.5D fabric, followed by mechanical Z-axis stitching reinforcement, can reduce weaving costs by more than 50% and the production cycle by more than 70%. Through innovation in preparation methods and material solutions, the manufacturing cost of the rudder heat shield cup was reduced by more than 70%, solving the problem of mass production, high performance, low cost, and rapid production of the rudder heat shield cup. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 A schematic diagram of the shape of a high-density, ablation-resistant rudder heat shield cup;

[0027] Figure 2 A flowchart of a method for manufacturing a high-density, ablation-resistant, heat-resistant rudder cup;

[0028] Figure 3 A schematic diagram of the assembly of a shaped device for a method of manufacturing a high-density ablation-resistant rudder heat shield cup;

[0029] Figure 4 A schematic diagram of the disassembled device for a method of manufacturing a high-density ablation-resistant rudder heat shield cup;

[0030] Figure 5 A schematic diagram showing the assembly relationship between the woven device and the fabric in a method for manufacturing a high-density ablation-resistant heat-resistant rudder cup.

[0031] Figure 6 A blank sample for a method of manufacturing a high-density, erosion-resistant, heat-resistant rudder cup;

[0032] Figure 7This is a diagram showing the positional relationship between an ablation sample and a small engine in an embodiment of a method for manufacturing a high-density ablation-resistant rudder heat shield.

[0033] In the figure: 1-Shaped device; 11-Clamping plate; 12-Positioning block; 13-Locking bolt; 14-Groove; 2-Fabric; 3-Kernel engine; 4-Ablation sample. Detailed Implementation

[0034] To make the technical problems, technical solutions, and beneficial effects of this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0035] In this application, the term "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0036] It should be understood that in the various embodiments of this application, the order of the above processes does not imply the order of execution. Some or all steps may be executed in parallel or sequentially. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0037] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0038] The weights of the relevant components mentioned in the embodiments of this application can refer not only to the specific content of each component, but also to the proportional relationship between the weights of the components. Therefore, any scaling up or down of the content of the relevant components according to the embodiments of this application is within the scope disclosed in the embodiments of this application. Specifically, the mass described in the embodiments of this application can be a well-known unit of mass in the chemical industry, such as µg, mg, g, or kg.

[0039] The following description is based on specific embodiments. Example 1

[0040] according to Figure 2 The flowchart shown illustrates the fabrication of a high-density, ablation-resistant rudder heat shield, as detailed below:

[0041] S1: Prepare 3D quartz fabric. Select 2.5D quartz fabric with dimensions of 600mm*600mm*30mm and perform Z-direction sewing. The density of the warp and weft yarns for sewing is 2 yarns / cm and 2 yarns / cm, respectively.

[0042] S2: Reference Figure 3 , Figure 4 , Figure 5 A weaving device 1 is prepared and used to weave the fabric 2. The weaving device 1 consists of clamping plates 11, positioning blocks 12, and locking bolts 13. Several threaded holes are formed at the edges of the clamping plates 11, which cooperate with the locking bolts 13. Several parallel grooves extending through the length or width of the clamping plates 11 are provided on the clamping plates 11. The grooves are 0.1 mm wide and 1 mm deep, with a spacing of 5 mm between any adjacent grooves. The number of clamping plates 11 can be increased depending on the amount of fabric. When weaving the fabric 2, the weaving device 1 is used to weave the fabric 2 between the clamping plates 11 and locks it in place using the locking bolts 13. The locking process uses positioning blocks 12 of different thicknesses to control the spacing between adjacent clamping plates 11.

[0043] Ten pieces of the three-dimensional quartz fabric obtained in step S1 were loaded into the weft-forming device, and the fiber volume content of the three-dimensional quartz fabric reached 52%.

[0044] S3: Place the fabric in an impregnation tank for silica sol impregnation, and then cure; the silica sol content is 25%. Specific procedures are as follows:

[0045] S3-1: After placing the fabric into the impregnation tank, a vacuum is drawn. When the vacuum degree is -0.093 MPa, the silica sol is drawn into the impregnation tank until the fabric is submerged. Then, the pressure is increased to 0.8 MPa and maintained for 2.5 hours.

[0046] S3-2: Remove the silica sol from the impregnation tank, and then heat it to cure, specifically: 60℃ for 18 hours; 130℃ for 7 hours;

[0047] S4: Remove the shaping device, place the fabric treated in step S3 into the impregnation tank, impregnate it with barium phenolic resin liquid, and then cure it; the barium phenolic resin liquid has a resin content of 69%, and the residual carbon content under nitrogen atmosphere at 800℃ is 61%. Specific operations are as follows:

[0048] S4-1: When placing the fabric into the impregnation tank, the normal of the large surface of the fabric should be parallel to the ground, and the spacing between the 10 fabric pieces should be 6mm.

[0049] S4-2: Preheat the fabric and barium phenolic liquid to 70°C and keep warm for 1 hour.

[0050] S4-3: Evacuate the impregnation tank. When the vacuum degree is ≤-0.09Mpa, draw barium phenolic liquid into the impregnation tank. After the barium phenolic liquid has submerged the fabric, stop evacuating the vacuum immediately.

[0051] S4-4: Circulating pressurization-vacuum solvent removal. One cycle is as follows: During pressurization, the impregnation tank is pressurized to 1 MPa and held for 1 hour. During vacuuming, the vacuum degree is ≤-0.09 MPa, and the process stops when no obvious bubbles escape from the barium phenolic liquid on the fabric surface. The cycle is repeated twice.

[0052] S4-5: Pressurize the impregnation tank to 2MPa for 4 hours.

[0053] S4-6: Curing. After applying pressure of 1.5MPa, perform the following cycles in one step: 90℃ for 2 hours; 120℃ for 2 hours; 140℃ for 2 hours; 160℃ for 6 hours.

[0054] S5: Machining of the rudder heat shield blank; the actual appearance of the rudder heat shield blank is as follows. Figure 6 As shown, the rudder heat shield cup is obtained, with the following external structure. Figure 1 As shown. Example 2

[0055] according to Figure 2 The flowchart shown illustrates the fabrication of a high-density, ablation-resistant rudder heat shield, as detailed below:

[0056] S1: Prepare three-dimensional quartz fabric. Select 2.5D quartz fabric with dimensions of 600mm*600mm*30mm and perform Z-direction sewing. The density of the warp and weft yarns of the sewing fibers is 1 thread / cm and 1 thread / cm, respectively.

[0057] S2: Reference Figure 3 , Figure 4 , Figure 5 A weaving device 1 is prepared and used to weave the fabric 2. The weaving device 1 consists of clamping plates 11, positioning blocks 12, and locking bolts 13. Several threaded holes are formed at the edges of the clamping plates 11, which cooperate with the locking bolts 13. Several parallel grooves extending through the length or width of the clamping plates 11 are provided on the clamping plates 11. The grooves are 0.3 mm wide and 1.5 mm deep, with a spacing of 10 mm between any adjacent grooves. The number of clamping plates 11 can be increased depending on the amount of fabric. When weaving the fabric 2, the weaving device 1 is used to weave the fabric 2 between the clamping plates 11 and locks it in place using the locking bolts 13. The locking process uses positioning blocks 12 of different thicknesses to control the spacing between adjacent clamping plates 11.

[0058] Eight pieces of the three-dimensional quartz fabric obtained in step S1 were loaded into the weft-forming device, and the fiber volume content of the three-dimensional quartz fabric reached 59%.

[0059] S3: Place the fabric preform into an impregnation tank for aluminum sol impregnation, and then cure it; the aluminum sol content is 30%. Specific procedures are as follows:

[0060] S3-1: After placing the fabric into the impregnation tank, a vacuum is drawn. When the vacuum degree is -0.095 MPa, aluminum sol is drawn into the impregnation tank until the fabric is submerged. Then, the pressure is increased to 1 MPa and maintained for 3 hours.

[0061] S3-2: Extract the aluminum sol from the impregnation tank, and then heat it to cure, specifically: 70℃, 15h; 140℃, 6h;

[0062] S4: Remove the shaping device, place the fabric treated in step S3 into the impregnation tank, impregnate it with magnesium phenolic resin liquid, and then cure it; the magnesium phenolic resin liquid has a resin content of 73%, and the residual carbon content under nitrogen atmosphere at 800℃ is 58%. Specific operations are as follows:

[0063] S4-1: When placing the fabric into the impregnation tank, the normal of the large surface of the fabric is parallel to the ground, and the spacing between the 10 fabric pieces is 7mm.

[0064] S4-2: Preheat the fabric and resin to 80°C and keep warm for 1.5 hours.

[0065] S4-3: Evacuate the impregnation tank. When the vacuum degree is ≤-0.09Mpa, pump the magnesium phenolic liquid into the impregnation tank. After the magnesium phenolic liquid has submerged the fabric, stop evacuating immediately.

[0066] S4-4: Circulating pressurization-vacuum solvent removal. One cycle is as follows: During pressurization, the impregnation tank is pressurized to 1.5 MPa and held for 1.5 hours. During vacuuming, the vacuum degree is ≤-0.09 MPa, and the process stops when no obvious bubbles escape from the magnesium phenolic liquid on the fabric surface. The cycle is repeated 3 times.

[0067] S4-5: Pressurize the impregnation tank to 3MPa for 6 hours.

[0068] S4-6: Curing. After applying pressure of 1.5MPa, perform the following cycles in one step: 90℃ for 3 hours; 120℃ for 3 hours; 140℃ for 3 hours; 160℃ for 4 hours.

[0069] S5: Machining of the rudder heat shield blank; the actual appearance of the rudder heat shield blank is as follows. Figure 6 As shown, the rudder heat shield cup is obtained, with the following external structure. Figure 1 As shown. Example 3

[0070] according to Figure 2 The flowchart shown illustrates the fabrication of a high-density, ablation-resistant rudder heat shield, as detailed below:

[0071] S1: Prepare 3D quartz fabric. Select 2.5D quartz fabric with dimensions of 1000mm*600mm*45mm and perform Z-direction sewing. The density of the warp and weft yarns of the sewing fibers is 3 threads / cm and 3 threads / cm, respectively.

[0072] S2: Reference Figure 3 , Figure 4 , Figure 5 A weaving device 1 is prepared and used to weave the fabric 2. The weaving device 1 consists of clamping plates 11, positioning blocks 12, and locking bolts 13. Several threaded holes are formed at the edges of the clamping plates 11, which cooperate with the locking bolts 13. Several parallel grooves extending through the length or width of the clamping plates 11 are provided on the clamping plates 11. The grooves are 0.5 mm wide and 2 mm deep, with a spacing of 12 mm between any adjacent grooves. The number of clamping plates 11 can be increased depending on the amount of fabric. When weaving the fabric 2, the weaving device 1 is used to weave the fabric 2 between the clamping plates 11 and locks it in place using the locking bolts 13. The locking process uses positioning blocks 12 of different thicknesses to control the spacing between adjacent clamping plates 11.

[0073] Twelve pieces of the three-dimensional quartz fabric obtained in step S1 are loaded into the weft-forming device. Eight layers of flow guide nets are laid between the three-dimensional quartz fabric and the weft-forming device. The fiber volume content of the three-dimensional quartz fabric reaches 62%.

[0074] S3: Place the fabric in an impregnation tank for zirconia sol impregnation, then cure; the zirconia sol has a sol content of 15%. Specific procedures are as follows:

[0075] S3-1: After placing the fabric into the impregnation tank, a vacuum is drawn. When the vacuum degree is -0.098 MPa, the zirconium oxide sol is drawn into the impregnation tank until the fabric is submerged. Then, the pressure is increased to 2 MPa and maintained for 5 hours.

[0076] S3-2: Remove the zirconium oxide sol from the container and then heat it to cure, specifically: 90℃ for 10 hours; 160℃ for 4 hours.

[0077] S4: Remove the shaping device, place the fabric treated in step S3 into the impregnation tank, impregnate it with high-carbon phenolic liquid, and then cure it; the high-carbon phenolic liquid has a resin content of 73%, and the residual carbon content under nitrogen atmosphere at 800℃ is 65%. Specific operations are as follows:

[0078] S4-1: When placing the fabric into the impregnation tank, the normal of the large surface of the fabric is parallel to the ground, and the spacing between the 10 fabric pieces is 12mm.

[0079] S4-2: Preheat the fabric and high-carbon phenolic liquid to 90°C and keep warm for 2 hours.

[0080] S4-3: Evacuate the impregnation tank. When the vacuum degree is ≤-0.09Mpa, draw the high-carbon phenolic liquid into the impregnation tank. After the high-carbon phenolic liquid has submerged the fabric, stop evacuating immediately.

[0081] S4-4: Cyclic pressurization-vacuum solvent removal. One cycle is as follows: During pressurization, the impregnation tank is pressurized to 2 MPa and held for 2 hours. During vacuuming, the vacuum degree is ≤ -0.09 MPa, and the process stops when no obvious bubbles escape from the high-carbon phenolic liquid on the fabric surface. The cycle is repeated 4 times.

[0082] S4-5: Pressurize the impregnation tank to 34MPa for 7 hours.

[0083] S4-6: Curing. After applying pressure of 3MPa, perform the following cycles in one step: 90℃ for 4 hours; 120℃ for 4 hours; 140℃ for 4 hours; 160℃ for 8 hours.

[0084] S5: Machining of the rudder heat shield blank; the actual appearance of the rudder heat shield blank is as follows. Figure 6 As shown, the rudder heat shield cup is obtained, with the following external structure. Figure 1 As shown.

[0085] Comparative Example 1

[0086] The shaping operation in step S2 was omitted, and the fabric was directly placed into the impregnation tank for impregnation and curing. The other steps were exactly the same as in Example 1.

[0087] Comparative Example 2

[0088] When the S4 fabric is placed in the impregnation tank, the normal of the large surface of the fabric is perpendicular to the ground, and the large surface of the fabric is parallel to the ground. The other steps are exactly the same as in Example 1.

[0089] Comparative Example 3

[0090] The cyclic pressurization-vacuum solvent removal operation in S4 is omitted. All other steps are identical to those in Example 1.

[0091] Comparative Example 4

[0092] The silica sol with a 25% adhesive content used for S3 impregnation was adjusted to a barium phenolic liquid with a 25% adhesive content, and the other steps were exactly the same as in Example 1.

[0093] The rudder heat shield blanks from the bottom of the impregnation tanks in Examples 1-3 and Comparative Examples 1-4 were used to test density, tensile strength, and small engine ablation rate. Density was tested according to GB / T1463. Tensile strength was tested according to GB / T1447-2005. The specific method for testing the small engine ablation rate was as follows: a 120mm*200*10mm ablation-resistant plate was machined from the blank. A kerosene engine was used to subject the ablation sample to high-temperature combustion gas flow erosion. The combustion chamber pressure was 1.4MPa, the combustion gas temperature was 2600-3000℃, and the ablation time was 10s. The linear ablation rate was calculated as: linear ablation amount / ablation time. The positional relationship between the ablation sample and the engine was as follows: Figure 7 As shown.

[0094] The performance test results of the rudder heat shield blanks prepared in Examples 1-3 and Comparative Examples 1-4 are shown in Table 1 below. The densities of the materials in Examples 1-3 and Comparative Examples 1-4 are 1.65 g / cm³. 3 1.68g / cm 3 1.73g / cm 3 1.60g / cm 3 1.52g / cm 3 1.49 g / cm 3 1.63g / cm 3 The ablation rates of the small engine were 0.08 mm / s, 0.06 mm / s, 0.05 mm / s, 0.14 mm / s, 0.17 mm / s, 0.20 mm / s, and 0.11 mm / s, respectively. The radial tensile strengths of the materials in Example 1 and Comparative Example 1 were 230 MPa and 160 MPa, respectively, and the weft tensile strengths were 300 MPa and 220 MPa, respectively.

[0095] Table 1 Summary of Performance Test Results of the Rudder Heat Protection Cup Blank

[0096]

[0097] The performance test results of the rudder heat shield blanks prepared in Examples 1-3 and Comparative Examples 1-4 show that the rudder heat shield material prepared in Examples 1-3 has high density, low ablation rate of small engines, and good ablation performance, making it suitable for use as a rudder heat shield. In Comparative Example 1, the shaping operation in step S2 was omitted, and the fabric was directly immersed in the impregnation tank for impregnation and curing. This resulted in a slight decrease in the fiber volume content of the heat shield fabric, and the fibers inside the fabric were in a twisted state, leading to a significant decrease in the density, tensile strength, and ablation performance of the rudder heat shield material. Furthermore, the omission of the shaping operation resulted in severe deformation of the fabric during impregnation, leading to significant material waste during the processing of the rudder heat shield. In Comparative Example 2, during step S4, the normal direction of the fabric's large surface was perpendicular to the phenolic liquid impregnation surface, while the fabric's large surface was parallel to the impregnation liquid surface. This resulted in poor solvent removal from the lower surface of the fabric during the solvent removal operation, leading to a significant increase in the porosity of the rudder heat shield material, a significant decrease in density, and a significant increase in the linear ablation rate. In Comparative Example 3, the cyclic pressurization-vacuum solvent removal operation in S4 was omitted, resulting in the highest porosity, lowest density, and highest linear ablation rate of the rudder heat shield material. Compared to Example 1, Comparative Example 4 changed the silica sol to barium phenolic liquid, and the prepared material lacked ablation-resistant inorganic particle reinforcement, leading to a decrease in the material's ablation performance.

[0098] Through the above experiments and analyses, it was found that the innovative process measures adopted in this application, such as inorganic ablation-resistant sol reinforcement, fabric state adjustment by shaping device, fabric placement state design, and circulating pressurization-vacuum solvent removal, have efficiently achieved the composite molding of multiple rudder heat protection cup fabrics in the same furnace. This is the key to the mass production, high performance, low cost, and rapid production of rudder heat protection cups.

[0099] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for manufacturing a high-density, ablation-resistant, heat-resistant rudder cup, characterized in that, The manufacturing method includes the following steps: S1. Z-direction stitching is performed using 2.5D quartz fabric; S2. The fabric obtained by sewing in step S1 is placed into the shaping device, and the fabric fibers are adjusted to a straight state by the shaping device, and the fiber volume content is increased to 50-65%; S3. Impregnate and cure the fabric with an inorganic sol; S4. Remove the shaping device, and impregnate and cure the inorganic sol-reinforced fabric with phenolic liquid to obtain the rudder heatproof cup blank; During phenolic liquid impregnation, multiple pieces of inorganic sol-reinforced fabric are first placed in the impregnation tank with the normal of the large surface of the fabric parallel to the ground. The multiple pieces of fabric are placed parallel to each other with a spacing of 5-15 mm. Then, the fabric and phenolic liquid are preheated to 60-90℃ and kept at this temperature for 1-2 hours. Next, the impregnation tank is evacuated to a vacuum degree of ≤-0.09MPa. Then, the phenolic liquid is drawn into the container until it covers the fabric. The impregnation is completed by cyclic pressurization and vacuuming. S5. Machining the rudder heat shield blank to obtain a density ≥1.6g / cm³. 3 The rudder heatproof cup; The curing process in step S3 is as follows: 50-100℃, 10-20h; 120-160℃, 4-8h; the curing process in step S4 is as follows: under 1-4MPa, sequentially 90℃, 2-4h; 120℃, 2-4h; 140℃, 2-4h; 160℃, 4-8h. The shaping device in step S2 includes a clamping plate, a positioning block, and a locking bolt. Several threaded holes are provided on the edge of the clamping plate, which are used in conjunction with the locking bolt. Several parallel grooves are provided on the clamping plate and extend through the length or width of the clamping plate. The grooves are 0.1-0.5 mm wide and 1-2 mm deep, and the distance between any two adjacent grooves is 5-15 mm. When the fabric is loaded into the shaping device, the fabric and the positioning block are placed between two clamping plates. When the locking bolt is tightened, the distance between the clamping plates is controlled by using positioning blocks of different thicknesses.

2. The method for manufacturing the high-density ablation-resistant heat shield cup according to claim 1, characterized in that, The inorganic sol mentioned in step S3 is silica sol, aluminum sol, silica-alumina sol or zirconium oxide sol, and the content of the inorganic sol is ≥10%.

3. The method for manufacturing the high-density ablation-resistant heat shield cup according to claim 1, characterized in that, The phenolic liquid mentioned in step S4 is barium phenolic, high carbon phenolic, aminophenolic, magnesium phenolic or boron phenolic, and the phenolic liquid has a gum content of 60-80% and a residual carbon content of ≥55% in nitrogen at 800℃.

4. The method for manufacturing the high-density ablation-resistant heat shield cup according to claim 1, characterized in that, The specific method for Z-direction sewing in step S1 is as follows: using a sewing machine device and quartz fiber sewing thread, the fabric is sewn. The density of the Z-direction sewing thread along the warp and weft directions of the 2.5D quartz fabric is 1-3 threads / cm and 1-3 threads / cm, respectively.

5. The method for manufacturing the high-density ablation-resistant heat shield cup according to claim 1, characterized in that, In step S3, during the inorganic sol impregnation, the shaping device and fabric are first placed into the impregnation tank and then a vacuum is drawn. When the vacuum degree is ≤-0.09MPa, the inorganic sol is drawn into the impregnation tank until the fabric is submerged. Then, the pressure is increased to 0.5-2MPa and maintained for 2-5 hours.

6. The method for manufacturing the high-density ablation-resistant heat shield cup according to claim 1, characterized in that, During the cyclic pressurization and vacuuming process, first pressurize the phenolic liquid to 1-2 MPa and hold it for 1-2 hours. After holding the pressure, extract the phenolic liquid from the container until the resin level is below the lower surface of the fabric. Vacuum the impregnation tank to a vacuum degree of ≤-0.09 MPa to remove the solvent from the phenolic liquid inside the fabric until no obvious bubbles emerge from the fabric surface. After vacuuming, pump the phenolic liquid back into the impregnation tank until the liquid level covers the fabric. Repeat the pressurization and vacuuming operation 2-5 times. After the cycle is complete, pressurize to 2-4 MPa and hold it for 4-8 hours.

7. The rudder heat shield cup obtained by the manufacturing method according to any one of claims 1-6, characterized in that, The density of the rudder heat shield cup is ≥1.6g / cm³. 3 The line ablation rate is <0.1 mm / s.

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