Functional gradient quartz fiber reinforced silicon dioxide ceramic-based composite material and preparation method thereof

Abstract

The invention discloses a functionally gradient quartz fiber reinforced silicon dioxide ceramic-based composite material and a preparation method thereof, and belongs to the technical field of fiber reinforced composite materials. According to the designability of the needled structure quartz fabric, the multifunctionality of the quartz fiber reinforced silicon dioxide ceramic matrix composite material is realized through the design of a fabric repeating unit.

Description

Technical Field

[0001] The present invention relates to a functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof, belonging to the technical field of fiber reinforced composite materials. Background Art

[0002] Quartz fiber reinforced silica composite materials are widely used in fields such as radomes, antenna windows, and rigid thermal insulation components due to their good high-temperature resistance, wave-transmitting performance, and mechanical properties. However, the performance of existing quartz fiber reinforced silica composite materials is often relatively single, unable to meet the applications under various working conditions, and prone to material waste. Currently, there are few reports on the preparation methods of functionally graded quartz fiber reinforced silica composite materials, and more focus on improving the performance of quartz fiber reinforced silica composite materials through density gradient methods. However, this process preparation method is relatively complex, has a long process cycle, and the manufacturing cost will increase.

[0003] In order to reduce the manufacturing cost of products, the reinforcing fabrics of quartz fiber reinforced silica composite materials are mostly prepared by needle punching process. The needle-punched structured quartz fiber fabric takes quartz fiber web felt and quartz fiber cloth layer as repeating units. The diversity of the arrangement of the web felt and cloth layer units makes the fabric have excellent designability and also provides the possibility for the functional diversity of quartz fiber reinforced silica composite materials.

[0004] In summary, it is very necessary to provide a functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof. Summary of the Invention

[0005] In order to solve the above-mentioned existing technical problems, the present invention provides a functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof.

[0006] A functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof, the method comprising the following steps:

[0007] (1) Prepare a functionally graded fabric along the thickness direction using quartz fibers, wherein the fabric repeating units are respectively one layer of cloth and one layer of web felt, two layers of cloth and one layer of web felt, and pure cloth layer;

[0008] (2) Impregnate the functionally graded fabric with silica sol, and then perform air drying;

[0009] (3) Repeat step (2) at least once to obtain a quartz fiber reinforced silica composite material blank;

[0010] (4) Subject the blank of the above material to high-temperature treatment to obtain a functionally graded quartz fiber reinforced silica ceramic matrix composite material;

[0011] Preferably, the type of the cloth layer is five - harness satin, and the areal density of the cloth layer is 270 - 320 g / m 2 , and the areal density of the mesh felt is 50 - 80 g / m 2 ;

[0012] Preferably, the volume density of the fabric is 0.5 - 0.8 g / cm 3 ;

[0013] Preferably, the solid content of the silica sol is 20 - 25%;

[0014] Preferably, the impregnation time of the silica sol on the quartz fabric is 24 - 72 h;

[0015] Preferably, the temperature of the blast drying is 200 - 250 °C, and the blast drying time is 8 - 12 h;

[0016] Preferably, the temperature of the high - temperature treatment is 500 - 800 °C, and the high - temperature treatment time is 2 - 3 h;

[0017] Preferably, the functional gradient fabric is a flat fabric, and the fabric thickness of each functional area is 5 - 10 mm;

[0018] Advantages of the present invention compared with the prior art:

[0019] (1) The functional gradient of the quartz fiber reinforced silica composite material of the present invention has strong designability, and the fabric structure is relatively simple, and the fabric structure can be flexibly designed according to specific needs;

[0020] (2) The present invention designs the fabric structure according to the actual working conditions of the application scenario, and can control the density of the quartz fiber reinforced silica composite material to the greatest extent, avoiding redundant weight;

[0021] (3) The present invention is simple to operate and low in cost, and broadens the application scenarios of the quartz fiber reinforced silica composite material. Specific embodiments

[0022] The present invention will be described in detail below with specific examples.

[0023] Example 1:

[0024] (1) A 300*300*20 mm functional gradient fabric is prepared using quartz fibers. Among them, the fabric repeating units are one layer of cloth and one layer of mesh felt and two layers of cloth and one layer of mesh felt, each with a thickness of 10 mm; the areal density of the cloth layer is 290 g / m 2 , and the areal density of the mesh felt is 60 g / m 2 ; the volume density of the fabric is 0.7 g / m 3 ;

[0025] (2) Impregnate the functional gradient fabric with silica sol for 48 h, and then conduct air drying at 200 °C for 8 h;

[0026] (3) Repeat step (2) five times to obtain a blank of quartz fiber reinforced silica composite;

[0027] (4) Heat-treat the blank of the above material at 600 °C for 2 h to obtain a functional gradient quartz fiber reinforced silica ceramic matrix composite;

[0028] (5) Cut the above functional gradient quartz fiber reinforced silica ceramic matrix composite along the central thickness direction and prepare relevant splines for performance testing. Among them, for the composite with a fabric repeat unit of one layer of cloth and one layer of mesh felt, the room temperature tensile strength is 25 - 30 MPa, the room temperature in-plane compressive strength is 80 - 110 MPa, the room temperature interlaminar shear strength is 8 - 12 MPa, and the thermal conductivity is 0.4 - 0.6 W / (m·K); for the composite with a fabric repeat unit of two layers of cloth and one layer of mesh felt, the room temperature tensile strength is 30 - 40 MPa, the room temperature in-plane compressive strength is 80 - 110 MPa, the room temperature interlaminar shear strength is 6 - 10 MPa, and the thermal conductivity is 0.4 - 0.6 W / (m·K);

[0029] Example 2:

[0030] (1) Prepare a 300*300*20 mm functional gradient fabric using quartz fiber, where the fabric repeat units are one layer of cloth and one layer of mesh felt and a pure cloth layer respectively, each with a thickness of 10 mm; the areal density of the cloth layer is 290 g / m 2 , and the areal density of the mesh felt is 60 g / m 2 ; the bulk density of the fabric is 0.7 g / m 3 ;

[0031] (2) Impregnate the functional gradient fabric with silica sol for 48 h, and then conduct air drying at 200 °C for 8 h;

[0032] (3) Repeat step (2) five times to obtain a blank of quartz fiber reinforced silica composite;

[0033] (4) Heat-treat the blank of the above material at 600 °C for 2 h to obtain a functional gradient quartz fiber reinforced silica ceramic matrix composite;

[0034] (5) Cut the above-mentioned functionally graded quartz fiber reinforced silica ceramic matrix composite along the central thickness direction and prepare relevant splines for performance testing. Among them, for the composite material with a fabric repeating unit of one layer of cloth and one layer of felt, the room temperature tensile strength is 25 - 30 MPa, the room temperature in-plane compressive strength is 80 - 110 MPa, the room temperature interlaminar shear strength is 8 - 12 MPa, and the thermal conductivity is 0.4 - 0.6 W / (m·K); for the composite material with a fabric repeating unit of pure cloth layer, the room temperature tensile strength is 35 - 55 MPa, the room temperature in-plane compressive strength is 60 - 90 MPa, the room temperature interlaminar shear strength is 5 - 8 MPa, and the thermal conductivity is 0.4 - 0.6 W / (m·K);

[0035] Example 3:

[0036] (1) Prepare a 300*300*20 mm functionally graded fabric using quartz fibers. Among them, the fabric repeating units are two layers of cloth and one layer of felt and pure cloth layer respectively, with a thickness of 10 mm each; the areal density of the cloth layer is 290 g / m 2 , and the areal density of the felt is 60 g / m 2 ; the bulk density of the fabric is 0.7 g / m 3 ;

[0037] (2) Impregnate the functionally graded fabric with silica sol for 48 h, and then perform forced-air drying at 200 °C for 8 h;

[0038] (3) Repeat step (2) 5 times to obtain a blank of quartz fiber reinforced silica composite material;

[0039] (4) Heat-treat the blank of the above material at 600 °C for 2 h to obtain a functionally graded quartz fiber reinforced silica ceramic matrix composite material;

[0040] (5) Cut the above-mentioned functionally graded quartz fiber reinforced silica ceramic matrix composite along the central thickness direction and prepare relevant splines for performance testing. Among them, for the composite material with a fabric repeating unit of two layers of cloth and one layer of felt, the room temperature tensile strength is 30 - 40 MPa, the room temperature in-plane compressive strength is 80 - 110 MPa, the room temperature interlaminar shear strength is 6 - 10 MPa, and the thermal conductivity is 0.4 - 0.6 W / (m·K); for the composite material with a fabric repeating unit of pure cloth layer, the room temperature tensile strength is 35 - 55 MPa, the room temperature in-plane compressive strength is 60 - 90 MPa, the room temperature interlaminar shear strength is 5 - 8 MPa, and the thermal conductivity is 0.4 - 0.6 W / (m·K);

[0041] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A functionally graded quartz fiber reinforced silica ceramic matrix composite and its preparation method, characterized in that, The method comprises the following steps: Step 1: Prepare a functionally gradient fabric along the thickness direction by using quartz fibers, wherein the fabric repeating units are respectively one layer of cloth and one layer of felt, two layers of cloth and one layer of felt, and a pure cloth layer; Step 2: Impregnate the functionally gradient fabric with silica sol, and then perform air drying; Step 3: Repeat Step 2 at least once to obtain a blank of quartz fiber reinforced silica composite; Step 4: Subject the blank of the above material to high-temperature treatment to obtain a functionally gradient quartz fiber reinforced silica ceramic matrix composite.

2. A functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof according to claim 1, characterized in that, The type of the cloth layer is five - harness satin, and the areal density of the cloth layer is 270 - 320 g / m 2 , and the areal density of the net felt is 50 - 80 g / m 2 .

3. A functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof according to claim 1, characterized in that, The bulk density of the fabric is 0.5 to 0.8 g / cm 3 .

4. A functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof according to claim 1, characterized in that, The solid content of the silica sol is 20-25%.

5. A functionally graded quartz fiber reinforced silica ceramic matrix composite and a preparation method thereof according to claim 1, wherein The impregnation time of the silica sol on the quartz fabric is 24-72 h.

6. The functional gradient quartz fiber reinforced silica ceramic matrix composite material according to claim 1 and its preparation method are characterized in that, The temperature of the air drying is 200-250 °C, and the time of the air drying is 8-12 h.

7. A functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof according to claim 1, characterized in that, The temperature of the high-temperature treatment is 500-800 °C, and the time of the high-temperature treatment is 2-3 h.

8. A functionally graded quartz fiber reinforced silica ceramic matrix composite material and a preparation method thereof according to claim 1, characterized in that, The functionally gradient fabric is a flat fabric, and the fabric thickness of each functional area is 5-10 mm.