A large thickness shaped quartz member and method of making

Abstract

The application discloses a large-thickness special-shaped quartz component and a preparation method, and belongs to the technical field of fiber-reinforced composite materials. The rigidity and processability of the quartz fiber-reinforced silica ceramic matrix composite material are utilized, the manufacturing process is optimized, and the manufacturing of the large-thickness special-shaped quartz component is realized.

Description

TECHNICAL FIELD

[0001] The application relates to a large-thickness special-shaped quartz component and a preparation method, and belongs to the technical field of fiber-reinforced composite materials. BACKGROUND

[0002] With the continuous increase of the flight Mach number and flight time of a hypersonic vehicle, the thermal protection problem of the vehicle becomes increasingly serious. In order to ensure that the internal temperature of a metal cabin is maintained at a low level, a large number of rigid heat insulation components need to be used on the surface of the metal cabin or the contact surface of the metal cabin and a high-temperature heat source such as an engine. In recent years, quartz components are widely used in the structure and thermal protection field of the hypersonic vehicle due to good high-temperature resistance and mechanical properties.

[0003] When the quartz component is applied to the surface of the metal cabin for heat insulation, the quartz component is often special-shaped, and the thickness direction size is large (greater than 50 mm) in many working conditions. The quartz component is machined from a regular blank of quartz fiber reinforced silica composite material. The large-thickness blank often has a hollow phenomenon due to the pulling forming process. After machining, the sample is detected by an industrial CT, and continuous hole defects are generated, and the hole size is basically greater than 1.8 mm 2 , which affects the bearing capacity of the component.

[0004] In summary, it is necessary to provide a large-thickness special-shaped quartz component and a preparation method. SUMMARY

[0005] The application provides a large-thickness special-shaped quartz component and a preparation method to solve the above technical problems.

[0006] A large-thickness special-shaped quartz component and a preparation method, the method comprising the following steps:

[0007] (1) using a cleaning agent to pretreat a quartz fiber flat fabric with a right-angle three-way structure;

[0008] (2) using high-concentration silica sol to impregnate the fabric for several hours, and then performing air blowing drying and high-temperature treatment;

[0009] (3) repeating step (2) twice to obtain a quartz component blank;

[0010] (4) performing rough machining on the quartz component blank, and machining the inner and outer cavities of the flat plate according to the component profile and leaving a 1-4 mm allowance; in addition, four circles with a diameter of 5-10 mm are opened at a distance of 5 mm from the edges of the flat plate;

[0011] (5) performing drying treatment on the rough machining blank of the material, and repeating step (3) once;

[0012] (6) the rough material is subjected to finishing treatment, and then dried after finishing;

[0013] (7) the rough material is immersed in low-concentration silica sol for several hours, and subjected to air blowing drying and high-temperature treatment;

[0014] (8) the step (7) is repeated for 1-3 times to obtain a large-thickness special-shaped quartz component;

[0015] Preferably, the cleaning agent is acetone or ethanol.

[0016] Preferably, the orthogonal three-way flat fabric XYZ has a yarn ply count of 442 or 224.

[0017] Preferably, the silica sol has a solid content of 20-25%, and the high-concentration silica sol has a density of 1.24-1.37 g / cm 3 ; the high-concentration immersion can be in the form of gradient immersion; the low-concentration silica sol has a density of 1.12-1.18 g / cm 3 ; and the silica sol immersion time of the quartz fabric is 24-72 h.

[0018] Preferably, the air blowing drying temperature is 200-250℃, and the air blowing drying time is 8-12 h.

[0019] Preferably, the high-temperature treatment temperature is 500-600℃, and the high-temperature treatment time is 2-3 h.

[0020] Compared with the prior art, the present application has the following beneficial effects:

[0021] (1) Compared with the method of improving the immersion effect by designing a density gradient fabric, the fabric structure of the present application is simple, does not need additional design, reduces the process, and reduces the manufacturing cost.

[0022] (2) The present application fully utilizes the rigidity and good processing performance of the quartz fiber reinforced silica composite material, and can be flexibly applied according to the shape and thickness of the quartz component.

[0023] (3) The present application has simple operation process and low manufacturing cost, and widens the application scenarios of large-thickness special-shaped quartz components. DETAILED DESCRIPTION

[0024] The present application will be described in detail below with reference to specific examples.

[0025] Example 1:

[0026] (1) The 442-structure orthogonal three-way flat fabric is cleaned with acetone, and the fabric size is 300*300*60 mm. After cleaning, it is placed in a fume hood for 3 days to dry.

[0027] (2) The above flat fabric was dipped in silica sol with a concentration of 1.35 g / cm 3 and 1.32 g / cm 3 for 48 h, and then air-dried at 200°C for 8 h;

[0028] (3) The blank of the above material was high-temperature treated at 600°C for 2 h to obtain a quartz component rough blank;

[0029] (4) The rough blank of the above quartz component was roughly processed, and the inner and outer cavities of the flat plate were machined according to the component profile with a 2 mm allowance. In addition, a 10 mm diameter circle was opened at a distance of 5 mm from the edge of the flat plate. After rough processing, the blank was air-dried at 250°C for 8 h;

[0030] (5) The above quartz component blank was dipped in silica sol with a concentration of 1.28 g / cm 3 and 1.25 g / cm 3 for 48 h, and then air-dried at 200°C for 8 h;

[0031] (6) The blank of the above material was high-temperature treated at 600°C for 2 h to obtain a quartz component fine blank;

[0032] (7) The blank of the above quartz component was finely processed. After fine processing, the quartz component was air-dried at 250°C for 8 h;

[0033] (8) The above quartz component was dipped in silica sol with a concentration of 1.14 g / cm 3 for 48 h, and then air-dried at 200°C for 8 h;

[0034] (9) The above quartz component was high-temperature treated at 600°C for 2 h to obtain a large-thickness special-shaped quartz component;

[0035] Example 2:

[0036] (1) The 442 structure orthogonal three-way flat fabric was cleaned with acetone, and the fabric size was 300*300*65 mm. After cleaning, it was placed in a fume hood to dry for 3 days;

[0037] (2) The above flat fabric was dipped in silica sol with a concentration of 1.36 g / cm 3 and 1.33 g / cm 3 for 48 h, and then air-dried at 200°C for 8 h;

[0038] (3) The rough blank of the above material is treated at 600°C for 2h to obtain a quartz component rough blank;

[0039] (4) The rough blank of the above quartz component is roughly processed, and the inner and outer cavities of the flat plate are shaped according to the component and with a 2mm allowance. In addition, a 10mm diameter circle is opened at a distance of 5mm from the edge of the four sides of the flat plate. After rough processing, the blank is air dried at 250°C for 8h;

[0040] (5) The above quartz component blank is immersed in silica sol with a concentration of 1.29g / cm 3 and 1.26g / cm 3 respectively for 48h, and then air dried at 200°C for 8h;

[0041] (6) The rough blank of the above material is treated at 600°C for 2h to obtain a quartz component rough blank;

[0042] (7) The rough blank of the above quartz component is roughly processed; after rough processing, the quartz component is air dried at 250°C for 8h;

[0043] (8) The above quartz component is immersed in silica sol with a concentration of 1.14g / cm 3 twice for 48h, and then air dried at 200°C for 8h;

[0044] (9) The above quartz component is treated at 600°C for 2h to obtain a large-thickness special-shaped quartz component;

[0045] Example 3:

[0046] (1) The 442 structure orthogonal three-way flat plate fabric is cleaned with acetone, and the fabric size is 300*300*70mm. After cleaning, it is placed in a fume hood to dry for 3 days;

[0047] (2) The above flat plate fabric is immersed in silica sol with a concentration of 1.37g / cm 3 and 1.34g / cm 3 respectively for 48h, and then air dried at 200°C for 8h;

[0048] (3) The rough blank of the above material is treated at 600°C for 2h to obtain a quartz component rough blank;

[0049] (4) Rough machining is performed on the blank of the quartz component, and the inner and outer cavities of the flat plate are machined according to the component profile with a 2mm allowance; in addition, a 10mm diameter circle is opened at a distance of 5mm from the edge of the four sides of the flat plate; after rough machining, the blank is air-dried at 250°C for 8h;

[0050] (5) The quartz component blank is immersed in silica sol with a concentration of 1.30g / cm 3 and 1.27g / cm 3 for 48h, and then air-dried at 200°C for 8h;

[0051] (6) The blank of the above material is high-temperature treated at 600°C for 2h to obtain a fine blank of the quartz component;

[0052] (7) The blank of the quartz component is fine machined; after fine machining, the quartz component is air-dried at 250°C for 8h;

[0053] (8) The quartz component is immersed in silica sol with a concentration of 1.14g / cm 3 for 48h twice, and then air-dried at 200°C for 8h;

[0054] (9) The quartz component is high-temperature treated at 600°C for 2h to obtain a large-thickness special-shaped quartz component;

[0055] The above merely describes preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement and improvement within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A thick, irregularly shaped quartz component and its preparation method, characterized in that, The method includes the following steps: Step 1: Pre-treat the orthogonal triaxial structure quartz fiber flat fabric with a cleaning agent; Step 2: The fabric is impregnated with a high-concentration silica sol for several hours, followed by forced-air drying and high-temperature treatment; Step 3: Repeat step 2 twice to obtain a quartz component blank; Step 4: Roughly machine the blank of the above-mentioned quartz component. The inner and outer cavities of the plate are machined according to the shape of the component, leaving a margin of 1 to 4 mm. In addition, a circle with a diameter of 5 to 10 mm is cut on each side of the plate, 5 mm away from the edge. Step 5: Dry the rough-machined blank of the above materials, and repeat step 3 once; Step 6: Perform finishing processing on the above-mentioned material blanks, followed by drying. Step 7: Impregnate the above materials with low-concentration silica sol for several hours, and then perform forced-air drying and high-temperature treatment; Step 8: Repeat step 7 one to three times to obtain a thick, irregularly shaped quartz component.

2. The thick, irregularly shaped quartz component and its preparation method according to claim 1, characterized in that, The cleaning agent is acetone or ethanol.

3. The thick, irregularly shaped quartz component and its preparation method according to claim 1, characterized in that, The orthogonal triaxial flat fabric has a ply count of 442 or 224 in the XYZ directions.

4. The thick, irregularly shaped quartz component and its preparation method according to claim 1, characterized in that, The silica sol has a solid content of 20-25%, and the density of the high-concentration silica sol is 1.24-1.37 g / cm³. 3 For high-concentration impregnation, a gradient impregnation method can be adopted; the density of low-concentration silica sol is 1.12–1.18 g / cm³. 3 The silica sol impregnation time of the quartz fabric is 24-72 hours.

5. The thick, irregularly shaped quartz component and its preparation method according to claim 1, characterized in that, The temperature of the blower drying is 200-250℃, and the time of the blower drying is 8-12 hours.

6. The thick, irregularly shaped quartz component and its preparation method according to claim 1, characterized in that, The high-temperature treatment is performed at a temperature of 500–600°C for 2–3 hours.