A method for preparing high-strength and high-density quartz fiber reinforced quartz composite material

Abstract

The invention discloses a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, which belongs to the field of quartz material technology. The preparation method includes: heat treating a quartz fiber prewoven body at 400-600 ° C for 130-240 min to obtain a pretreated body; placing the pretreated body in a mold, evacuating it to <96kPa, and then injecting a composite sol, and impregnating it for 60-120 min; keeping the sol liquid level submerged on the top of the pretreated body, applying a 0.2-0.5MPa pulsating pressure field, and drying it at 30-50 ° C for 450-900 min to form a blank; and densifying and sintering the blank. The pulsating pressure field drives the sol to migrate in a directional manner and maintains a constant liquid level, so that the process operation is simplified, the penetration depth of high components is significantly improved, and the matrix uniformity is enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of quartz materials, and particularly relates to a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material. Background Art

[0002] Quartz fiber-reinforced quartz-based composites, due to their excellent dielectric properties, thermal stability, and mechanical strength, play an irreplaceable role in the field of wave-transmitting aerospace components. The current mainstream preparation process utilizes a sol-gel method, where a quartz fiber preform is densified through repeated impregnation and drying cycles using an acid silica sol. Existing technologies, such as patent CN118026717B, have made progress in improving impregnation efficiency through a staged, descending liquid level capillary impregnation process, but significant limitations remain.

[0003] The capillary action height in this process is limited to less than 200mm. For large components exceeding 500mm in height, the sol has difficulty effectively penetrating the core area through capillary force, resulting in a sharp increase in the component's axial density, seriously affecting the uniformity of product performance. Furthermore, to maintain the capillary infiltration effect, multiple manual sol discharge operations are required, which not only prolongs the process cycle but also introduces air due to frequent system openings, forming bubble defects within the prefabricated structure and reducing the reliability of the material structure.

[0004] Therefore, existing technologies struggle to achieve both uniform impregnation of large components and ease of operation. On the one hand, the inherent height limit of capillary action restricts the upper limit of product size, while on the other hand, complex manual intervention steps increase quality risks and production costs. There is an urgent need to develop a new preparation method that can overcome the capillary height limit while simplifying the operation process. Summary of the Invention

[0005] In response to the shortcomings of the existing technology, the present invention provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, comprising: S1, heat treating a quartz fiber prewoven body at 400-600°C for 130-240 minutes to obtain a pretreated body; S2, placing the pretreated body in a mold, evacuating it to a vacuum degree of less than 96 kPa, injecting a composite sol, and impregnating it for 60-120 minutes; S3, maintaining the composite sol liquid level submerged above the top of the pretreated body, applying a pulsating pressure field of 0.2-0.5 MPa, and drying at 30-50°C for 450-900 minutes to form a blank; S4, sequentially performing a densification treatment and a sintering treatment on the blank.

[0006] In some embodiments, the pressure variation cycle of the pulsating pressure field in S3 is 30s for increasing pressure and 60s for decreasing pressure.

[0007] In some embodiments, the composite sol comprises: 40-45 parts by mass of acid silica sol and 3-8 parts by mass of ZrO 2 sol, and the viscosity of the composite sol is less than 15 mPa·s.

[0008] In some embodiments, the pressure range of the pulsating pressure field is 0.3-0.4 MPa.

[0009] In some embodiments, the ZrO2 sol is added in an amount of 5-7 parts by mass.

[0010] In some embodiments, after the S3 drying is completed, a 20-50 mm area at the bottom of the blank is cut off.

[0011] In some embodiments, the quartz fiber prewoven body has a height of 500-1500 mm and a thickness of 6-30 mm.

[0012] In some embodiments, the specific steps of S4 include: S41, vacuum impregnating the blank in 40-45% acid silica sol for 60-120 minutes, and drying at 150-200°C for 100-150 minutes; S42, vacuum impregnating the blank in 20-30% acid silica sol for 60-120 minutes; S43, sintering at 700-800°C for 200-300 minutes.

[0013] In some embodiments, the vacuum degree of S41 and S42 is both 100 kPa.

[0014] In some embodiments, in S43, the sintering further includes heat preservation, and the heat preservation time is 150-200 minutes.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. By applying a 0.2-0.5MPa pulsating pressure field and keeping the sol liquid level constant, manual discharge is eliminated, which simplifies the operation process, reduces bubble defects, increases the penetration depth, and completely fills high components.

[0017] 2. By adding 3-8 parts by mass of ZrO2 sol to the composite formula, the wettability of the sol is enhanced, the penetration efficiency is improved, and the height direction density deviation rate is reduced.

[0018] 3. Through staged concentration impregnation, two impregnations can achieve the densification effect of traditional 5-7 cycles, and the matrix density is uniform.

[0019] 4. By cutting off the 20-50mm area at the bottom of the blank, the density gradient caused by gravity sedimentation is eliminated in a targeted manner, and the overall uniformity is improved in exchange for less material loss.

[0020] 5. Through the pulsating pressure cycle and low-temperature drying, the sol can be directional migrated in the pores and solidified simultaneously, avoiding the deformation of the fiber skeleton and ensuring the mechanical integrity of the product. DETAILED DESCRIPTION

[0021] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0022] The present invention provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, comprising:

[0023] S1. heat-treating the quartz fiber prewoven body at 400-600° C. for 130-240 min to obtain a pretreated body;

[0024] S2. Place the pretreated body in a mold, evacuate to a vacuum degree of <96 kPa, inject the composite sol, and immerse for 60-120 minutes;

[0025] S3, keeping the composite sol liquid surface submerged on the top of the pre-treated body, applying a pulsating pressure field of 0.2-0.5 MPa, and drying at 30-50° C. for 450-900 min to form a blank;

[0026] S4, performing densification treatment and sintering treatment on the blank in sequence.

[0027] In S1, the quartz fiber preform is heat-treated at 400-600°C for 130-240 minutes to remove the sizing agent and organic impurities on the fiber surface. This process activates the fiber surface, improving the interfacial bonding strength with the subsequent sol, while also eliminating capillary action caused by impurities and creating clean pore channels for sol penetration.

[0028] In S2, the pretreated body is placed in a mold and vacuum is applied. This negative pressure environment displaces trapped gas from the fiber pores, creating a low-pressure permeation path. Driven by the pressure differential, the injected composite sol rapidly fills the pores. A 60-120-minute impregnation period ensures the sol fully occupies the microscopic pore network. This step overcomes the capillary height limitations of traditional static impregnation and lays the foundation for subsequent directional migration.

[0029] In S3, a pulsating pressure field first drives directional migration. During the pressurization phase (0.2-0.5 MPa), the external pressure field applies positive pressure to the composite sol surface, forcing the sol to migrate along the capillary network within the pretreated body toward the unsaturated region at the top. The high-pressure environment overcomes the sol's inherent viscous resistance and the frictional resistance of the capillary walls, driving the sol beyond the height limit of traditional capillary action (>200 mm) and achieving deep penetration. During the depressurization phase, a sudden drop in pressure causes dissolved gases within the sol to precipitate due to supersaturation. Simultaneously, bubbles trapped in the pores of the pretreated body escape in the reverse direction along the capillaries under the pressure differential. This process removes gas obstructions and restores the capillary permeation pathway. Low-temperature drying and curing are then carried out. The solvent is slowly evaporated at 30-50°C, allowing sol particles to accumulate in an orderly manner within the capillaries, forming a dense gel skeleton. During the pressurization phase, the liquid sol is pushed into the micro-voids created by drying and shrinkage. During the depressurization phase, volatiles released during the formation of the gel skeleton are expelled, ultimately forming a dense blank matrix with uniform density. The drying process works in conjunction with the pulsating pressure to ensure that the gel is evenly distributed within the pores, eliminating core-surface density differences.

[0030] In S4, the densification treatment involves secondary impregnation of micropores and sintering to transform the gel into a continuous quartz phase, ultimately achieving a strong and tough bond between the matrix and the fiber.

[0031] By driving the sol to migrate in a directional manner through a pulsating pressure field and keeping the liquid level constant, the process operation is simplified, the penetration depth of high components is significantly improved, and the uniformity of the matrix is ​​enhanced.

[0032] In some embodiments, the pressure variation cycle of the pulsating pressure field in S3 is 30s for increasing pressure and 60s for decreasing pressure.

[0033] A 30-second pressure increase and 60-second pressure reduction cycle is repeated to create directional pressure. Each pressure increase pushes the sol toward high-resistance areas (such as fiber bundle intersections and micropore blind ends). During the pressure reduction phase, gas is expelled to clear space for the next penetration cycle. This cycle continues until drying is complete, achieving uniform sol distribution across a height range of 500-1500 mm.

[0034] During operation, the pulsating pressure field replaces the liquid level drop function required for manual drainage. Increasing pressure simulates the osmotic drive of "liquid level rise," while decreasing pressure simulates the gas expulsion of "exposure drying," without the risk of gas intrusion. The sol is always kept submerged above the top of the pretreatment body, eliminating air-sol interface disturbances caused by a drop in the liquid level. Sol in the high-pressure area (near the liquid surface) is forced to migrate toward the low-pressure area (top), automatically balancing sol settling due to gravity and overcoming the discontinuous filling defects caused by manual drainage.

[0035] In some embodiments, the composite sol comprises: 40-45 parts by mass of acid silica sol and 3-8 parts by mass of ZrO 2 sol, and the viscosity of the composite sol is less than 15 mPa·s.

[0036] The composite sol provides a high-solid content matrix through 40-45 parts by mass of acid silica sol, and at the same time introduces 3-8 parts by mass of ZrO2 sol to reduce the contact angle of the liquid-solid interface, thereby enhancing the spreading ability of the sol on the inner wall of the capillary. This ratio, while maintaining a viscosity of less than 15mPa·s, not only exceeds the solid content of traditional acid silica sol, but also improves the efficiency of the sol's vertical migration through the wetting modification effect of ZrO2, achieving uniform filling of high components (500-1500mm) in a single impregnation, reducing the number of subsequent densification treatments.

[0037] In some embodiments, the pressure range of the pulsating pressure field is 0.3-0.4 MPa. The amount of the ZrO2 sol added is 5-7 parts by mass.

[0038] By limiting the pulsating pressure field to 0.3-0.4MPa and the ZrO2 sol to 5-7 parts by mass, the migration efficiency of the sol to break through high-resistance pores under high-pressure drive is guaranteed, and the deformation of the fiber skeleton caused by excessive pressure is avoided; at the same time, the optimized ZrO2 addition amount strikes a balance between significantly reducing the contact angle and maintaining the stability of the sol viscosity, thereby achieving complete filling of high-component pores while reducing process fluctuations, and reducing the risk of gelation caused by sol agglomeration.

[0039] In some embodiments, after the S3 drying is completed, a 20-50 mm area at the bottom of the blank is cut off. The quartz fiber prewoven body has a height of 500-1500 mm and a thickness of 6-30 mm.

[0040] In some embodiments, the quartz fiber prewoven body has a height of 1500 mm and a thickness of 18 mm.

[0041] By removing a 20-50mm area from the bottom of the blank, the uneven sol settling caused by gravity in 500-1500mm high components is eliminated, while retaining the uniform structure of the main structure formed by the pulsating pressure field. This operation only removes less than 10% of the bottom area, ensuring overall product density consistency with minimal material loss and avoiding the core surface performance degradation caused by increased height in traditional processes. It is important to note that the height of the quartz fiber prefabricated body refers to the length of the capillary channels in the quartz fiber, while the thickness is the cross-sectional dimension perpendicular to the height.

[0042] In some embodiments, the specific step S4 includes:

[0043] S41, vacuum impregnate the blank into 40-45% acid silica sol for 60-120 minutes, and dry it at 150-200°C for 100-150 minutes;

[0044] S42, vacuum impregnating the blank into 20-30% acid silica sol for 60-120 minutes;

[0045] S43. Sinter at 700-800℃ for 200-300min.

[0046] In some embodiments, the vacuum degree of S41 and S42 is both 100 kPa.

[0047] In some embodiments, in S43, the sintering further includes heat preservation, and the heat preservation time is 150-200 minutes.

[0048] In S41, the blank is first impregnated with 40-45% high-concentration acid silica sol under a vacuum of 100kPa. The high solid content is used to preferentially occupy large-sized pores and build a dense skeleton. The main structure is then dried and solidified at a medium temperature of 150-200°C while retaining the capillary channels. In S42, it is then switched to a second impregnation with 20-30% low-concentration acid silica sol. The low viscosity allows it to penetrate into the fine pores that were not filled in the early stage, and the same vacuum degree (100kPa) maintains the unobstructed penetration path. In S43, sintering is carried out at 700-800°C for 200-300 minutes, and the amorphous SiO2 is converted into a continuous quartz phase with a 150-200-minute insulation. At the same time, the ZrO2 component introduced in the early stage inhibits the cristobalite phase transformation and reduces thermal stress cracks. This process uses a step-by-step filling mechanism of high concentration to build the skeleton and low concentration to fill the micropores, replacing the traditional multiple cycles with two impregnations. The constant vacuum environment and optimized insulation time ensure the thermodynamic balance of the phase change process and eliminate local over-burning or under-burning defects.

[0049] The method of the present invention will be described in detail below with reference to embodiments, comparative examples and experimental data.

[0050] Example 1

[0051] This embodiment provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, comprising the following steps:

[0052] S1. Take a quartz fiber prewoven body with a height of 1000 mm and a thickness of 18 mm, place the prewoven body in an electric furnace, heat it to 500° C. at a rate of 10° C. / min, and keep it at this temperature for 185 minutes to obtain a pretreated body.

[0053] S2. Place the pretreated body into a steel mold with a sealing cover, evacuate to 94 kPa, inject the composite sol, and soak for 90 minutes. The composite sol is 42.5 parts by mass of acid silica sol + 5.5 parts by mass of ZrO2 sol, with a viscosity of 12 mPa·s.

[0054] S3: Maintaining the sol liquid level submerged above the top of the pretreated body, connect a compressed air system to apply a pulsating pressure of 0.35 MPa, cycling the pressure increase for 30 seconds and the pressure decrease for 60 seconds. Dry at 40°C for 675 minutes to form a blank. After drying, remove a 35 mm area from the bottom of the blank.

[0055] S41, immersing the blank in 42.5% acid silica sol under 100 kPa vacuum for 90 minutes, taking it out and drying it at 175°C for 125 minutes;

[0056] S42, immersing again in 25% acid silica sol under 100 kPa vacuum for 90 min;

[0057] S43. Place the product in an electric furnace and sinter it at 750° C. for 250 minutes, then keep it warm for 175 minutes to obtain a high-strength and high-density quartz fiber reinforced quartz composite material.

[0058] Example 2

[0059] This embodiment provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, comprising the following steps:

[0060] S1. Take a quartz fiber prewoven body with a height of 1000 mm and a thickness of 18 mm, place the prewoven body in an electric furnace, heat it to 400° C. at a rate of 10° C. / min, and keep it at this temperature for 130 minutes to obtain a pretreated body.

[0061] S2. Place the pretreated body into a steel mold with a sealing cover, evacuate to 94 kPa, inject the composite sol, and immerse for 60 minutes. The composite sol is 40 parts by mass of acid silica sol + 3 parts by mass of ZrO2 sol, with a viscosity of 12 mPa·s.

[0062] S3: Maintaining the sol liquid level submerged above the top of the pretreated body, connect a compressed air system to apply a pulsating pressure of 0.2 MPa, cycling the pressure increase for 30 seconds and the pressure decrease for 60 seconds. Dry at 30°C for 450 minutes to form a blank. After drying, remove a 20 mm area from the bottom of the blank.

[0063] S41, immersing the blank in 40% acid silica sol under 100 kPa vacuum for 60 minutes, taking it out and drying it at 150°C for 100 minutes;

[0064] S42, immersing again in 20% acid silica sol under 100 kPa vacuum for 60 min;

[0065] S43. Place the product in an electric furnace and sinter it at 700° C. for 200 minutes, then keep it warm for 150 minutes to obtain a high-strength and high-density quartz fiber reinforced quartz composite material.

[0066] Example 3

[0067] This embodiment provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, comprising the following steps:

[0068] S1. Take a quartz fiber prewoven body with a height of 1000 mm and a thickness of 18 mm, place the prewoven body in an electric furnace, heat it to 600° C. at a rate of 10° C. / min, and keep it at this temperature for 240 minutes to obtain a pretreated body.

[0069] S2. Place the pretreated body into a steel mold with a sealing cover, evacuate to 94 kPa, inject the composite sol, and immerse for 120 minutes. The composite sol is 45 parts by mass of acid silica sol + 8 parts by mass of ZrO2 sol, with a viscosity of 12 mPa·s.

[0070] S3: Maintaining the sol liquid level submerged above the top of the pretreated body, connect a compressed air system to apply a pulsating pressure of 0.5 MPa, cycling the pressure increase for 30 seconds and the pressure decrease for 60 seconds. Dry at 50°C for 900 minutes to form a blank. After drying, remove a 50 mm area from the bottom of the blank.

[0071] S41, immerse the blank in 45% acid silica sol under 100 kPa vacuum for 120 minutes, take it out and dry it at 200°C for 150 minutes;

[0072] S42, immersing again in 30% acid silica sol under 100 kPa vacuum for 120 min;

[0073] S43. Place the product in an electric furnace and sinter it at 800° C. for 300 minutes, then keep it warm for 200 minutes to obtain a high-strength and high-density quartz fiber reinforced quartz composite material.

[0074] Comparative Example 1

[0075] This comparative example provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, which differs from Example 1 in that:

[0076] The pulsating pressure field was cancelled and the sol was discharged manually in stages: the liquid level was lowered by 200 mm every 180 minutes of drying (a total of 4 discharges). The other steps were the same as those in Example 1.

[0077] Comparative Example 2

[0078] This comparative example provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, which differs from Example 1 in that:

[0079] The composite sol contains only 42.5 parts by mass of acid silica sol (excluding ZrO2 sol), and the other steps are the same as those in Example 1.

[0080] Comparative Example 3

[0081] This comparative example provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, which differs from Example 1 in that:

[0082] The pulsating pressure field is changed to a constant pressure of 0.35 MPa, that is, the pressure increase / decrease cycle is cancelled, and the other steps are the same as those in Example 1.

[0083] Comparative Example 4

[0084] This comparative example provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, which differs from Example 1 in that:

[0085] In S3, the bottom area of ​​the blank is not removed, and the other steps are the same as those in Example 1.

[0086] Comparative Example 5

[0087] This comparative example provides a method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, which differs from Example 1 in that:

[0088] S41 and S42 used the same concentration of sol (both 42.5% acid silica sol), and the other steps were the same as in Example 1.

[0089] The properties of the high-strength and high-density quartz fiber reinforced quartz composite materials prepared by the methods provided in the above embodiments and comparative examples were tested. The testing method is as follows:

[0090] 1. Density uniformity:

[0091] Measurement method: Cut the finished product into 5 samples (top / upper middle / middle / lower middle / bottom) at equal distances along the height direction. The cutting section of each sample is 20×20 mm. 3 Then boil the sample in boiling water for 2 hours and immerse it in room temperature deionized water for 24 hours until constant weight is reached. Use a 0.1mg precision electronic balance to weigh the wet weight of the saturated water sample. W w , dry the sample at 105℃ to constant weight, and weigh the dry weight W d , and then calculate its apparent density according to the following formula:

[0092] ,

[0093] in, W s for The weight of the sample suspended in water, r water Take 1g / cm 3 ;

[0094] Then, according to the apparent density of the five samples r , calculate the average density ;

[0095] Calculate the standard deviation of the five samples according to the following formula s :

[0096] ,

[0097] in, r i is the density of a single sample;

[0098] and density deviation rate d :

[0099] ,

[0100] in, r top is the density of the topmost sample, r bottom is the density of the bottom sample.

[0101] 2. Penetration depth:

[0102] Measurement method: After S3 is dried, cut the cross section along the height direction of the blank, spray 0.1% methylene blue solution for dyeing for 30 seconds, rinse with clean water and measure the height of the blue area (sol penetration area).

[0103] 3. Bubble defect density:

[0104] Measurement method: polish the finished product and count the 1cm under a 20x magnifying glass. 2 The number of bubbles in the area (diameter > 50 μm).

[0105]

[0106] Experimental results analysis

[0107] In Example 1, the density standard deviation is 0.0085 g / cm 3 The material is highly uniform inside, with a density deviation of 0.56% indicating almost no attenuation at a height of 1000mm. The material is completely filled at a penetration depth of 1000mm, with only 3 bubble defects per cm. 2 The process stability was verified.

[0108] In Example 2, the density standard deviation is 0.0092 g / cm 3 The penetration depth of 980 mm is slightly lower than that of Example 1, but the deviation rate is 0.62% and the bubbles are 4 / cm 2 Still meeting high uniformity requirements.

[0109] In Example 3, the penetration depth was 1500 mm and the concentration was 0.0078 g / cm 3 The low standard deviation and 0.51% deviation rate show the adaptability of the optimized parameters to super-large components, with 2 bubbles / cm 2 The best in the whole group.

[0110] In Comparative Example 1, the number of bubble defects increased to 18 / cm 2 (500% higher than Example 1), standard deviation 0.032 g / cm 3 This indicates that multiple mold openings introduce structural disturbances, and although the penetration depth reaches 1000 mm, the uniformity is severely deteriorated.

[0111] In Comparative Example 2, the lack of zirconia resulted in insufficient sol wettability, resulting in full filling at the top and significant underfilling at the bottom. The penetration depth was only 720 mm. However, due to the absence of bubble interference, the density within the same height layer was relatively uniform. The 3.2% deviation rate indicated significant density decay with height, demonstrating the key role of zirconia in the vertical migration of the sol. In contrast, in Comparative Example 1, artificial drainage resulted in discontinuous sol filling and random bubble distribution. These random bubbles caused significant local fluctuations, resulting in a higher σ value than in Comparative Example 2.

[0112] In Comparative Example 3, the penetration depth of 800 mm was insufficient and the number of bubbles was 15 / cm. 2 , explaining the necessity of periodic pressure changes for gas discharge and complete permeation.

[0113] In Comparative Example 4, the standard deviation is 0.021 g / cm 3 It is 2.5 times that of Example 1, and the deviation rate is 1.9%, which confirms the negative impact of the bottom sedimentation area on the overall uniformity.

[0114] In Comparative Example 5, the standard deviation is 0.019 g / cm 3 It increases significantly, indicating that a single concentration cannot take into account both macropore filling and micropore penetration, resulting in a decrease in matrix density.

[0115] In summary, the pulsating pressure field (0.2-0.5 MPa) combined with zirconia-modified sol (3-8 parts by mass) can stably achieve complete penetration of 500-1500 mm high components (penetration depth = component height), with a density standard deviation of ≤0.0092 g / cm 3 20-50mm bottom cut-off compensates for gravity sedimentation effect, making the height density deviation rate ≤0.62%; staged concentration impregnation (40-45%→20-30%) controls bubble defects to ≤4 / cm 2 The whole process is 24 times more efficient than manual discharge technology.

[0116] The applicant declares that the present invention uses the above-described embodiments to illustrate the detailed process flow of the present invention, but the present invention is not limited to the above-described detailed process flow, that is, it does not mean that the present invention must rely on the above-described detailed process flow to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent replacements for various raw materials in the products of the present invention, addition of auxiliary ingredients, and selection of specific methods, etc., are all within the scope of protection and disclosure of the present invention.

Claims

1. A method for preparing a high-strength and high-density quartz fiber reinforced quartz composite material, characterized in that: include: S1. heat-treating the quartz fiber prewoven body at 400-600° C. for 130-240 min to obtain a pretreated body; S2. Place the pretreated body in a mold, evacuate to a vacuum degree of <96 kPa, inject the composite sol, and immerse for 60-120 minutes; S3, maintaining the composite sol liquid surface submerged on the top of the pretreated body, applying a pulsating pressure field of 0.2-0.5 MPa, drying at 30-50° C. for 450-900 min to form a blank, and then cutting off a 20-50 mm area at the bottom of the blank; the composite sol comprises: 40-45 parts by mass of acid silica sol and 3-8 parts by mass of ZrO2 sol, and the composite sol has a viscosity of less than 15 mPa·s; S4, performing densification treatment and sintering treatment on the blank in sequence; The specific steps of S4 include: S41, vacuum impregnate the blank into 40-45% acid silica sol for 60-120 minutes, and dry it at 150-200°C for 100-150 minutes; S42. Vacuum impregnate the blank into 20-30% acid silica sol for 60-120 minutes.

2. The method according to claim 1, characterized in that The pressure variation cycle of the pulsating pressure field in S3 is 30s for increasing pressure and 60s for decreasing pressure.

3. The method according to claim 1, characterized in that The pressure range of the pulsating pressure field is 0.3-0.4 MPa.

4. The method according to claim 1, wherein The amount of the ZrO2 sol added is 5-7 parts by mass.

5. The method according to claim 1, wherein The quartz fiber prewoven body has a height of 500-1500 mm and a thickness of 6-30 mm.

6. The method according to claim 1, characterized in that Said S4 further comprises: S43. Sinter at 700-800℃ for 200-300min.

7. The method according to claim 1, characterized in that The vacuum degrees of S41 and S42 are both 100 kPa.

8. The method according to claim 6, characterized in that In the S43, the sintering step further includes heat preservation, and the heat preservation time is 150-200 minutes.

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