High-temperature glue with adjustable temperature resistance limit as well as preparation method and application of high-temperature glue

Abstract

The invention discloses a high-temperature glue with an adjustable temperature resistance limit, and a preparation method and application thereof. The preparation method comprises the following steps: step 1, obtaining a basic component, a filler component, a cross-linking agent and water with target weights; step 2, adding the raw material components into a stirring container at intervals, uniformly mixing, and standing at room temperature to obtain high-temperature glue with a plurality of temperature-resistant limits; the temperature resistance limits of the high-temperature glue are 800 to 900 DEG C, 1000 to 1100 DEG C, 1300 to 1400 DEG C and 1500 to 1600 DEG C. The invention further discloses a preparation method of the high- The temperature resistance limit of the high-temperature glue can be regulated and controlled, and different temperature ranges of CVI-SiC deposition are met.

Description

Technical Field

[0001] The present application relates to the technical field of high temperature adhesives, and in particular to a high temperature adhesive with adjustable temperature resistance limit, and a preparation method and application thereof. Background Art

[0002] Ceramic matrix composites (CMC-SiC, including C / SiC and SiC / SiC) have excellent properties such as high temperature resistance, low density, high strength and toughness, pseudo-plastic mechanical behavior, notch insensitivity and no catastrophic damage. It is an internationally recognized new type of thermal structural material and is widely used in the aerospace field.

[0003] At present, in the field of aerospace, it is necessary to use a split graphite mold to limit the fiber preform made of ceramic matrix composite materials, and then perform multiple CVI-SiC deposition in a vacuum deposition furnace. After the deposition is completed, the graphite mold needs to be demolded. The split graphite mold is usually bonded with high-temperature glue and then the fiber preform is limited for deposition. In order to protect ceramic matrix composite products, the adhesive is usually required to fail in the temperature range of 1200℃ to 1300℃. The existing organic adhesives and inorganic adhesives have temperature resistance ranges of 150~550℃ and 1500~2000℃ respectively, and cannot fail at high temperatures during deposition at 1200~1300℃; at the same time, the highest heat resistance limit of high-temperature glue cannot meet the different deposition temperature ranges, causing the bonding effect in the graphite mold to fail too early or too late, resulting in the size and demolding difficulties of the fiber preform.

[0004] In view of this, a high temperature adhesive with adjustable temperature resistance limit and a preparation method and application thereof are proposed. Summary of the invention

[0005] The purpose of the present invention is to provide a high-temperature adhesive with adjustable temperature resistance limit and a preparation method and application thereof, so as to achieve adjustable temperature resistance limit of the high-temperature adhesive to meet different temperature ranges of CVI-SiC deposition, and solve the problem of too early or too late deposition of the high-temperature adhesive in the prior art.

[0006] In order to solve the above technical problems, the present invention adopts the following solutions:

[0007] A method for preparing a high-temperature adhesive with adjustable temperature resistance limit comprises the following steps:

[0008] Step 1, obtaining target weights of base components, filler components, crosslinking agents and water;

[0009] Step 2, adding each raw material component into a stirring container at intervals and mixing evenly, and standing at room temperature to obtain high temperature adhesives with multiple temperature resistance limits;

[0010] The temperature resistance limits of the high temperature adhesive include 800-900°C, 1000-1100°C, 1300-1400°C, and 1500-1600°C.

[0011] Furthermore, in step 1:

[0012] The basic component is composed of 4 to 10 parts of PVA polyvinyl alcohol, 4 to 5 parts of aluminum dihydrogen phosphate, 3 to 4 parts of acrylamide, and 2 to 5 parts of NN-methylenebisacrylamide by weight;

[0013] The filler component is composed of 9 to 15 parts of graphite powder and 82 to 95 parts of silicon carbide powder by weight;

[0014] The cross-linking agent is composed of 1 to 2 parts of borax by weight;

[0015] The weight portion of the water is 15 to 25 parts.

[0016] Furthermore, the particle sizes of the graphite powder and silicon carbide powder are 500-700 mesh and 600-900 mesh respectively, and the graphite powder and silicon carbide powder are tested for impurities using a carbon-sulfur analyzer to ensure that the graphite powder and silicon carbide powder used are free of impurities.

[0017] Furthermore, in the step 2, the stirring container is preheated to 40-60°C.

[0018] Furthermore, water is added first, and then the raw material components are added into the stirring container in the order of the base component, the filler component and the cross-linking agent, while stirring at 600 to 900 revolutions per minute.

[0019] Furthermore, the interval time is 1 to 3 minutes.

[0020] The interval time here refers to the basic components, PVA polyvinyl alcohol, aluminum dihydrogen phosphate, acrylamide, NN-methylenebisacrylamide, are added to the stirring container in the order of PVA, aluminum dihydrogen phosphate, acrylamide, and NN-methylenebisacrylamide, and then stirred for 1 to 3 minutes; then the filler components, graphite powder and silicon carbide powder, are added to the stirring container in the order of graphite powder and silicon carbide powder, and then stirred for 1 to 3 minutes; then the crosslinking agent borax is added and mixed and stirred evenly. The filler components and crosslinking agents added later can fully play the role of high-temperature modified fillers and high-temperature failure fillers in the basic components, and improve the viscosity and strength of the high-temperature glue.

[0021] Furthermore, the standing time at room temperature is 8 to 25 hours.

[0022] A high temperature adhesive with adjustable temperature resistance limit is prepared by the above-mentioned preparation method of a high temperature adhesive with adjustable temperature resistance limit. The adjustable temperature resistance limit ranges of the high temperature adhesive are 800-900°C, 1000-1100°C, 1300-1400°C, and 1500-1600°C.

[0023] By changing the ratio of different raw material components to adjust the temperature resistance limit range of the high temperature adhesive, the prepared high temperature adhesive can meet the different temperature ranges of CVI-SiC deposition, prevent the bonding effect of the graphite mold from failing prematurely, and facilitate demolding of the fiber preform.

[0024] The invention discloses an application of a high temperature adhesive with adjustable temperature resistance limit, which is applied to the bonding of graphite molds in the aerospace field and then the CVI-SiC deposition heat treatment.

[0025] Furthermore, the coating thickness of the high temperature glue in the graphite fixture is 0.8 to 1.2 mm.

[0026] The beneficial effects of the present invention are as follows: by changing the ratio of the basic component, the filler component and the cross-linking agent, the temperature resistance limit of the high-temperature adhesive can be adjusted, and the temperature resistance limit can reach up to 1500-1600°C. The bonding effect of the graphite mold is prevented from failing prematurely during the CVI-SiC deposition heat treatment, which facilitates the demoulding of the fiber preform. At the same time, when the basic component, the filler component and the cross-linking agent are added in sequence in an interval addition manner, the latter component and the former component are uniformly mixed, thereby improving the bonding effect of the high-temperature adhesive. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] The relative arrangement of components and steps, the numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

[0030] Additionally, descriptions of well-known structures, functions, and configurations may be omitted for clarity and conciseness.One of ordinary skill in the art will recognize that various changes and modifications may be made to the examples described herein without departing from the spirit and scope of the present disclosure.

[0031] Technologies, methods, and apparatus known to ordinary technicians in the relevant field may not be discussed in detail, but where appropriate, such technologies, methods, and apparatus should be considered part of the authorization specification.

[0032] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0033] The present application discloses a high temperature adhesive with adjustable temperature resistance limit and a preparation method thereof, comprising the following steps:

[0034] Step 1: Obtain target weights of base components, filler components, crosslinking agents, and water;

[0035] The basic component is composed of 4 to 10 parts of PVA polyvinyl alcohol, 4 to 5 parts of aluminum dihydrogen phosphate, 3 to 4 parts of acrylamide, and 2 to 5 parts of NN-methylenebisacrylamide by weight.

[0036] The filler component is composed of 9 to 15 parts of graphite powder and 82 to 95 parts of silicon carbide powder by weight; the particle sizes of the graphite powder and silicon carbide powder are 500 to 700 meshes and 600 to 900 meshes respectively, and the graphite powder and silicon carbide powder are tested for impurities using a carbon-sulfur analyzer to ensure that there are no impurities in the graphite powder and silicon carbide powder.

[0037] The cross-linking agent is composed of 1 to 2 parts of borax by weight;

[0038] The weight portion of the water is 15 to 25 parts.

[0039] Step 2: Preheat the stirring container to 40-60°C, add water to the stirring container first, then add the basic components in sequence (add PVA polyvinyl alcohol, aluminum dihydrogen phosphate, acrylamide, NN-methylenebisacrylamide) after an interval of 1-3 minutes, add the filler components (add graphite powder and silicon carbide powder in this order) after an interval of 1-3 minutes, and finally add borax while stirring, mix and stir until the material is uniform in color and evenly dispersed, and then stand at room temperature for 8-25 hours to obtain the high temperature glue.

[0040] Example 1

[0041] This embodiment provides a high temperature adhesive, and the preparation method thereof is as follows:

[0042] Step 1: Weigh the following raw material components by weight: basic component, 7 parts of PVA polyvinyl alcohol, 4 parts of aluminum dihydrogen phosphate, 3 parts of acrylamide, 3 parts of NN-methylenebisacrylamide; filler component, 9 parts of graphite powder, 92 parts of silicon carbide powder; cross-linking agent, 1 part of borax and 20 parts of water; the particle sizes of the graphite powder and silicon carbide powder are 700 mesh and 600 mesh respectively, and the graphite powder and silicon carbide powder are tested for impurities using a carbon-sulfur analyzer to ensure that there are no impurities in the graphite powder and silicon carbide powder.

[0043] Step 2: Preheat the stirring container to 40°C, add water to the stirring container first, then add the basic components in sequence (add PVA polyvinyl alcohol, dihydrogen aluminum phosphate, acrylamide, NN-methylenebisacrylamide) after a 1 minute interval, add the filler components (add graphite powder and silicon carbide powder in this order) after a 1 minute interval, and finally add borax, stirring while adding, mixing and stirring until the material is uniform in color and evenly dispersed, and then stand at room temperature for 15 hours to obtain the high temperature glue.

[0044] Application of high temperature adhesive in CVI-SiC deposition:

[0045] Wipe the surface of the graphite mold to be bonded with acetone or anhydrous ethanol, leave it for 2 minutes, and wait until the surface is dry and free of oil stains; apply 1 mm thick high-temperature glue on the surface to be bonded, wipe the excess high-temperature glue on the side with acetone or anhydrous ethanol, and let it stand at 35°C for 8 hours. After assembling the graphite mold and the fiber preform, CVI-SiC deposition is performed, the set temperature is 1600°C, the heating rate is 15°C / min, the insulation time is 1.5h, the cooling rate is 50°C / min, and it is cooled to 30°C. Take out the graphite mold and the fiber preform for demolding.

[0046] The shear adhesion failure temperature of the high temperature adhesive at 1600° C. was measured by a high temperature shear adhesion test. The failure temperature of the high temperature adhesive prepared in this embodiment is 1500-1600° C.

[0047] Example 2

[0048] This embodiment provides a high temperature adhesive, and the preparation method thereof is as follows:

[0049] Step 1: Weigh the following raw material components by weight: basic component, 8 parts of PVA polyvinyl alcohol, 4 parts of aluminum dihydrogen phosphate, 3 parts of acrylamide, 3 parts of NN-methylenebisacrylamide; filler component, 10 parts of graphite powder, 90 parts of silicon carbide powder; cross-linking agent, 1 part of borax and 23 parts of water; the particle sizes of the graphite powder and silicon carbide powder are 700 mesh and 600 mesh respectively, and the graphite powder and silicon carbide powder are tested for impurities using a carbon-sulfur analyzer to ensure that there are no impurities in the graphite powder and silicon carbide powder.

[0050] Step 2: Preheat the stirring container to 50°C, add water to the stirring container first, then add the basic components in sequence (PVA polyvinyl alcohol, aluminum dihydrogen phosphate, acrylamide, NN-methylenebisacrylamide) after a 2-minute interval, add the filler components (graphite powder and silicon carbide powder) after a 1-minute interval, and finally add borax while stirring until the material is uniform in color and evenly dispersed, and then stand at room temperature for 10 hours to obtain the high-temperature glue.

[0051] Application of high temperature adhesive in CVI-SiC deposition:

[0052] Wipe the surface of the graphite mold to be bonded with acetone or anhydrous ethanol, leave it for 3 minutes, and wait until the surface is dry and free of oil stains; apply 0.8 mm thick high-temperature glue on the surface to be bonded, wipe the excess high-temperature glue on the side with acetone or anhydrous ethanol, and let it stand at 50°C for 6 hours. After assembling the graphite mold and the fiber preform, CVI-SiC deposition is performed, the set temperature is 1400°C, the heating rate is 20°C / min, the insulation time is 2h, the cooling rate is 60°C / min, and it is cooled to 40°C. Take out the graphite mold and the fiber preform for demolding.

[0053] The shear adhesion failure temperature of the high temperature adhesive at 1400° C. was measured by a high temperature shear adhesion test. The failure temperature of the high temperature adhesive prepared in this embodiment is 1300-1400° C.

[0054] Example 3

[0055] This embodiment provides a high temperature adhesive, and the preparation method thereof is as follows:

[0056] Step 1: Weigh the following raw material components by weight: basic component, 8 parts of PVA polyvinyl alcohol, 5 parts of aluminum dihydrogen phosphate, 3 parts of acrylamide, 3 parts of NN-methylenebisacrylamide; filler component, 10 parts of graphite powder, 90 parts of silicon carbide powder; cross-linking agent, 1 part of borax and 23 parts of water; the particle sizes of the graphite powder and silicon carbide powder are 700 mesh and 600 mesh respectively, and the graphite powder and silicon carbide powder are tested for impurities using a carbon-sulfur analyzer to ensure that there are no impurities in the graphite powder and silicon carbide powder.

[0057] Step 2: Preheat the stirring container to 60°C, add water to the stirring container first, then add the basic components in sequence (add PVA polyvinyl alcohol, aluminum dihydrogen phosphate, acrylamide, NN-methylenebisacrylamide) after an interval of 3 minutes, add the filler components (add graphite powder and silicon carbide powder in this order) after an interval of 3 minutes, and finally add borax, stirring while adding, mixing and stirring until the material is uniform in color and evenly dispersed, and then stand at room temperature for 20 hours to obtain the high temperature glue.

[0058] Application of high temperature adhesive in CVI-SiC deposition:

[0059] Wipe the surface of the graphite mold to be bonded with acetone or anhydrous ethanol, leave it for 2 minutes, and wait until the surface is dry and free of oil stains; apply 1.2 mm thick high-temperature glue on the surface to be bonded, wipe the excess high-temperature glue on the side with acetone or anhydrous ethanol, and let it stand at 40°C for 10 hours. After assembling the graphite mold and the fiber preform, CVI-SiC deposition is performed, the set temperature is 1100°C, the heating rate is 20°C / min, the insulation time is 2h, the cooling rate is 60°C / min, and it is cooled to 50°C. Take out the graphite mold and the fiber preform for demolding.

[0060] The shear adhesion failure temperature of the high temperature adhesive at 1100° C. was measured by a high temperature shear adhesion test. The failure temperature of the high temperature adhesive prepared in this embodiment is 1000-1100° C.

[0061] Example 4

[0062] This embodiment provides a high temperature adhesive, and the preparation method thereof is as follows:

[0063] Step 1: Weigh the following raw material components by weight: basic component, 10 parts of PVA polyvinyl alcohol, 5 parts of aluminum dihydrogen phosphate, 4 parts of acrylamide, 4 parts of NN-methylenebisacrylamide; filler component, 15 parts of graphite powder, 83 parts of silicon carbide powder; cross-linking agent, 2 parts of borax and 18 parts of water; the particle sizes of the graphite powder and silicon carbide powder are 700 mesh and 600 mesh respectively, and the graphite powder and silicon carbide powder are tested for impurities using a carbon-sulfur analyzer to ensure that there are no impurities in the graphite powder and silicon carbide powder.

[0064] Step 2: Preheat the stirring container to 40°C, add water to the stirring container first, then add the basic components in sequence (add PVA polyvinyl alcohol, dihydrogen aluminum phosphate, acrylamide, NN-methylenebisacrylamide) after a 1 minute interval, add the filler components (add graphite powder and silicon carbide powder in this order) after a 1 minute interval, and finally add borax, stirring while adding, mixing and stirring until the material is uniform in color and evenly dispersed, and then stand at room temperature for 15 hours to obtain the high temperature glue.

[0065] Application of high temperature adhesive in CVI-SiC deposition:

[0066] Wipe the surface of the graphite mold to be bonded with acetone or anhydrous ethanol, leave it for 2 minutes, and wait until the surface is dry and free of oil stains; apply 1 mm thick high-temperature glue on the surface to be bonded, wipe the excess high-temperature glue on the side with acetone or anhydrous ethanol, and let it stand at 50°C for 10 hours. After assembling the graphite mold and the fiber preform, CVI-SiC deposition is performed, the set temperature is 900°C, the heating rate is 15°C / min, the insulation time is 1.5h, the cooling rate is 50°C / min, and it is cooled to 30°C. Take out the graphite mold and the fiber preform for demolding.

[0067] The shear adhesion failure temperature of the high temperature adhesive at 900° C. was measured by a high temperature shear adhesion test. The failure temperature of the high temperature adhesive prepared in this embodiment is 800-900° C.

[0068] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a high temperature adhesive with adjustable temperature resistance limit, characterized in that: The following steps are involved: Step 1, obtaining target weights of base components, filler components, crosslinking agents and water; Step 2, adding each raw material component into a stirring container at intervals and mixing evenly, and standing at room temperature to obtain high temperature adhesives with multiple temperature resistance limits; The temperature resistance limits of the high temperature adhesive include 800-900°C, 1000-1100°C, 1300-1400°C, and 1500-1600°C.

2. The method for preparing a high temperature adhesive with adjustable temperature resistance limit according to claim 1, characterized in that: In the step 1: The basic component is composed of 4 to 10 parts of PVA polyvinyl alcohol, 4 to 5 parts of aluminum dihydrogen phosphate, 3 to 4 parts of acrylamide, and 2 to 5 parts of NN-methylenebisacrylamide by weight; The filler component is composed of 9 to 15 parts of graphite powder and 82 to 95 parts of silicon carbide powder by weight; The cross-linking agent is composed of 1 to 2 parts of borax by weight; The weight portion of the water is 15 to 25 parts.

3. The method for preparing a high temperature adhesive with adjustable temperature resistance limit according to claim 2, characterized in that: The particle sizes of the graphite powder and silicon carbide powder are 500-700 meshes and 600-900 meshes respectively, and a carbon-sulfur analyzer is used to detect impurities in the graphite powder and silicon carbide powder.

4. The method for preparing a high temperature adhesive with adjustable temperature resistance limit according to claim 2, characterized in that: In the step 2, the stirring container is preheated to 40-60°C.

5. The method for preparing a high temperature adhesive with adjustable temperature resistance limit according to claim 2, characterized in that: First add water, then add each raw material component into the stirring container in the order of base component, filler component and cross-linking agent, stirring while adding, 600-900 rpm.

6. The method for preparing a high temperature adhesive with adjustable temperature resistance limit according to claim 5, characterized in that: The interval time is 1 to 3 minutes.

7. The method for preparing a high temperature adhesive with adjustable temperature resistance limit according to claim 5, characterized in that: The standing time at room temperature is 8 to 25 hours.

8. A high temperature adhesive with adjustable temperature resistance limit, characterized in that: The high temperature adhesive is prepared by the method for preparing a high temperature adhesive with adjustable temperature resistance limit as described in any one of claims 1 to 7, wherein the temperature resistance limit adjustment range of the high temperature adhesive is 800-900°C, 1000-1100°C, 1300-1400°C, and 1500-1600°C.

9. Application of a high temperature adhesive with adjustable temperature resistance limit, characterized in that: It is used in the aerospace field for bonding graphite molds and then undergoing CVI-SiC deposition heat treatment.

10. The use of a high temperature adhesive with adjustable temperature resistance limit according to claim 9, characterized in that: The coating thickness of the high temperature glue in the graphite mold is 0.8 to 1.2 mm.