High temperature resistant and infrared radiation resistant alumina fiber static sealing material and preparation method thereof

Abstract

The invention discloses a high temperature resistant and infrared radiation resistant alumina fiber static sealing material and a preparation method thereof, belonging to the fields of sealing material technology and thermal protection material technology. Alumina twisted yarn is made by twisting alumina fiber and controlling the twist; alumina twisted yarn is made by plying multiple strands; alumina ceramic powder, sunscreen component, adhesive and diluent are stirred evenly to prepare a composite impregnation liquid; the composite impregnation liquid is used to impregnate and compound the alumina twisted yarn, and then dried to make an alumina composite wire; the alumina composite wire is used to weave the alumina fiber static sealing material. The material has the functions of high temperature resistance, infrared radiation resistance, sealing filling and heat insulation and heat resistance.

Description

Technical Field

[0001] The invention relates to a flexible high-temperature-resistant and infrared-resistant alumina fiber static sealing material and a preparation method thereof, belonging to the technical fields of sealing material technology and heat protection material technology. Background Art

[0002] The high-temperature thermal protection of aerospace vehicles, high-temperature engines, high-temperature kilns and generators in the industrial field, etc., require thermal insulation protection design for the overall structure. They are facing a high-temperature and long-term use environment. Their gap sealing, thermal sealing of moving parts, thermal sealing of opening and closing devices, etc. need to solve the technical problems of high-temperature heat leakage. If heat leakage occurs, the temperature of the low-temperature area in the working area will rise, which will seriously affect the normal operation of the equipment. In the past, graphite seals, aramid / carbon fiber organic composite packings, metal bellows seals, etc. were used for high-temperature sealing treatment at 400-600℃. For high-temperature sealing above 600℃, aluminum silicate wool braided packing was used, and the temperature resistance can only meet the environmental conditions of about 1000℃. The aerospace and industrial fields continue to put forward new technical requirements for special heat sealing materials, which require functions such as resistance to 1000-1500℃, flexibility, and heat insulation sealing. Faced with the lack of such heat sealing material preparation technology, it is urgent to carry out relevant preparation technology research and development, which limits the development of related equipment technology. Therefore, high-performance high-Mach aircraft have put forward high requirements for ultra-high temperature flexible thermal sealing at 1000-1500℃, and it is necessary to solve the technical difficulties in the preparation of ultra-high temperature, flexible, and infrared radiation-resistant thermal insulation sealing materials.

[0003] In addition, patent CN108977954A discloses a method for preparing an antioxidant composite fabric, which includes the following steps: yarn production, yarn dipping, fabric weaving, preparation of post-treatment liquid, and post-treatment. After the structural design of the yarn and the subsequent post-finishing treatment, the antioxidant properties of the fabric can be improved. However, it is a two-dimensional plane woven fabric, using a through-the-core yarn process, which belongs to a fabric manufacturing process, using ordinary fibers such as terylene, wool and polyethylene, and can only be used at room temperature to 100°C, and cannot be used in the above-mentioned ultra-high temperature environment.

[0004] In view of this, a flexible high temperature resistant and infrared radiation resistant alumina fiber static sealing material and a preparation method thereof are proposed. Summary of the invention

[0005] In order to solve the problems of shortcomings in the background technology, the present invention provides a flexible, high-temperature, and infrared-resistant alumina fiber static sealing material and a preparation method thereof, which can be used for thermal insulation sealing materials for ultra-high temperature parts of high-Mach aircraft, thermal insulation sealing materials for gaps in industrial high-temperature equipment, etc. It is a high-reliability thermal sealing material component for aerospace and industrial high-temperature equipment, and has advanced high-temperature thermal sealing application value.

[0006] A method for preparing a high temperature resistant and infrared radiation resistant alumina fiber static sealing material comprises the following steps:

[0007] (1) twisting alumina fibers to control the twist and prepare alumina twisted yarns;

[0008] (2) plying a plurality of the alumina twisted yarns to prepare alumina twisted plied yarns;

[0009] (3) preparing alumina ceramic powder, a light shielding agent component, a binder and a diluent in a mass ratio of (1-5):(1-8):(0.5-10):100, stirring evenly, and preparing a composite impregnation solution;

[0010] (4) using the composite impregnation liquid to impregnate and composite the alumina twisted plied yarn, and then drying it, and after drying, an alumina composite wire is obtained;

[0011] (5) Using the alumina composite wire according to different weaving methods and weaving cross-sectional shapes, adjusting the weaving volume fraction, performing online weaving, and performing a heating treatment after weaving to prepare an alumina fiber static sealing material.

[0012] Preferably, the tex number of the alumina fiber ranges from 60 to 600 tex; the twist ranges from 10 to 180 twists / m.

[0013] Preferably, the number of the combined strands is 2 to 10 strands.

[0014] Preferably, the alumina ceramic powder is nano-scale.

[0015] Preferably, the sunscreen component is one, two or three of chromium oxide, silicon carbide, nickel oxide, iron oxide, manganese dioxide, lanthanum oxide, titanium dioxide and the like.

[0016] Preferably, the adhesive is one of silica sol and silicone resin.

[0017] Preferably, the diluent is one of ethanol and acetone.

[0018] Preferably, the impregnation composite method is a one-step production method of continuously online impregnating, drying and winding the alumina twisted plied yarn.

[0019] Preferably, the drying method is hot air circulation heating drying; the drying temperature is 60 to 150°C;

[0020] Preferably, the weaving method is one of two-dimensional three-directional, three-dimensional four-directional, and three-dimensional five-directional.

[0021] Preferably, the braided cross-sectional shape is one of circular and rectangular.

[0022] Preferably, the braiding volume fraction is 30% to 50%.

[0023] Preferably, the temperature of the heating treatment is 500-600° C., and the time of the heating treatment is 10-120 min.

[0024] A high temperature resistant and infrared radiation resistant alumina fiber static sealing material is prepared by the method.

[0025] The beneficial effects of the present invention compared with the prior art are as follows:

[0026] (1) The present invention innovatively adopts the single-strand fiber twisting of step (1), which can adjust the preload of each fiber bundle by twisting, affect the degree of contact and stacking of the fiber bundles, and make them more dense; adopts step (2) to combine multiple fiber strands, and the different number of strands can adjust the fineness of the fiber braiding structure, which has different effects on the flexibility, compressibility, and sealing of the fiber structure; adopts the composite functional component of step (4), and the addition of components can optimize the barrier effect of the fiber structure against high-temperature infrared radiation, and play a heat insulation effect; adopts the three-dimensional braiding of step (5), which is to use the processed fiber yarn bundle through three-dimensional braiding to become a rope-shaped braided body, and the cross-section can be circular or rectangular. Using fiber twisting, plying and braiding process to control the flexibility, compressibility and other properties of the fiber braiding structure is a preparation technology for ultra-high temperature static sealing materials.

[0027] (2) The present invention innovatively designs a three-dimensional fiber weaving structure of "point-line" structural units composed of fiber composite yarns and nano-functional powders. The fibers and the nano-powders with shading functions are weakly connected and composited to maintain the coordinated performance of fiber flexibility and deformation. The functional powders are evenly dispersed in the weaving structure and have the functions of resistance to high temperatures of 1500°C, resistance to infrared radiation, sealing and filling, and heat insulation.

[0028] (3) The flexible, high-temperature-resistant, infrared-resistant alumina fiber static sealing material prepared by the present invention has strong structural design, including cross-sectional dimensions, continuous length, flexibility, compression deformability, etc. It has the characteristics of ultra-high temperature resistance, flexible deformability, high-temperature infrared radiation resistance, and good structural integrity. It is an excellent high-temperature static sealing material with universal promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1A It is a schematic diagram of a single-strand alumina fiber yarn.

[0030] Figure 1B It is a schematic diagram of the structure of alumina single fiber twisted yarn.

[0031] Figure 2 It is a schematic diagram of the structure of the alumina twisted and stranded composite wire of the present invention.

[0032] Figure 3 It is a schematic diagram of the cross-sectional structure of the alumina fiber static sealing material of the present invention. DETAILED DESCRIPTION

[0033] In order to make the above features and advantages of the present invention more obvious and easy to understand, embodiments are given below and described in detail with reference to the accompanying drawings.

[0034] Example 1

[0035] This embodiment provides a method for preparing a flexible, high temperature resistant and infrared radiation resistant alumina fiber static sealing material, which is prepared according to the following method:

[0036] (1) 60 tex alumina fiber was twisted with a twist of 90 twists / m to produce alumina twisted yarn.

[0037] (2) Ten strands of twisted yarn are plied together to produce an alumina twisted plied yarn.

[0038] (3) preparing a composite impregnation liquid, wherein the mass ratio of nano-alumina ceramic powder, sunscreen component, adhesive and diluent is 1:3:2:100 respectively, the sunscreen is chromium trioxide, silicon carbide, nickel oxide, the adhesive is silica sol, and the diluent is ethanol, stirring evenly and setting aside.

[0039] (4) The alumina twisted plied yarn is impregnated and composited with a composite impregnation liquid. The specific method is a one-step preparation method of the yarn continuous online impregnation, drying, and winding. The hot air circulation heating drying is adopted. The drying temperature is 100°C. After the drying is completed, the alumina composite wire is prepared.

[0040] (5) Alumina composite wire is used in a rectangular cross-section shape according to a three-dimensional four-way weaving method, and the weaving volume fraction is designed to be 35%. Online weaving is performed, and after the weaving is completed, a temperature treatment is performed at 500°C for 30 minutes to prepare an alumina fiber static sealing material, thereby obtaining a flexible, high-temperature, and infrared-resistant alumina fiber static sealing material.

[0041] Product performance test: The static sealing material prepared by the above method has a cross-sectional size of 8mm*12mm, a dimensional shrinkage rate of ≤2% after treatment at 1500℃ for 30min, a minimum flexible bending radius of 2cm, and a room temperature thermal conductivity of 0.035W / (Km).

[0042] Example 2

[0043] This embodiment provides a method for preparing a flexible, high temperature resistant and infrared radiation resistant alumina fiber static sealing material, which is prepared according to the following method:

[0044] (1) 350 tex alumina fiber was twisted with a twist of 180 twists / m to produce alumina twisted yarn.

[0045] (2) Five twisted yarns are plied together to produce alumina twisted plied yarns.

[0046] (3) preparing a composite impregnation liquid, wherein the mass ratio of nano-alumina ceramic powder, sunscreen component, adhesive and diluent is 3:1:0.5:100 respectively, the sunscreen is chromium trioxide, the adhesive is silica sol, and the diluent is ethanol. Stir well and set aside.

[0047] (4) The alumina twisted plied yarn is impregnated and composited with a composite impregnation liquid. The specific method is a one-step preparation method of the yarn continuous online impregnation, drying, and winding. The hot air circulation heating drying is adopted. The drying temperature is 60°C. After the drying is completed, the alumina composite wire is prepared.

[0048] (5) Alumina composite wire is used in a circular cross-sectional shape according to a three-dimensional five-way weaving method, and the weaving volume fraction is designed to be 30%. Online weaving is performed, and after the weaving is completed, a temperature treatment is performed at 600°C for 10 minutes to prepare an alumina fiber static sealing material, thereby obtaining a flexible, high-temperature, and infrared-resistant alumina fiber static sealing material.

[0049] Product performance test: The static sealing material prepared by the above method has a cross-sectional size of 6mm*10mm. After being treated at 1500℃ for 30min, the dimensional shrinkage rate is ≤2%, the minimum flexible bending radius can reach 1cm, and the room temperature thermal conductivity is 0.031W / (Km).

[0050] Example 3

[0051] This embodiment provides a method for preparing a flexible, high temperature resistant and infrared radiation resistant alumina fiber static sealing material, which is prepared according to the following method:

[0052] (1) 600 tex alumina fiber was twisted with a twist of 10 twists / m to produce alumina twisted yarn.

[0053] (2) Two twisted yarns are plied together to produce an alumina twisted plied yarn.

[0054] (3) Prepare a composite impregnation liquid, wherein the mass ratio of nano-alumina ceramic powder, sunscreen component, adhesive and diluent is 5:8:10:100 respectively, the sunscreen is silicon carbide and nickel oxide, the adhesive is silicone resin, and the diluent is acetone. Stir well and set aside.

[0055] (4) The alumina twisted plied yarn is impregnated and composited with a composite impregnation liquid. The specific method is a one-step preparation method of the yarn continuous online impregnation, drying, and winding. The hot air circulation heating drying is adopted. The drying temperature is 150° C. After the drying is completed, the alumina composite wire is prepared.

[0056] (5) Alumina composite wire is used in a rectangular cross-section shape according to a two-dimensional three-way weaving method, and the weaving volume fraction is designed to be 50%. Online weaving is performed, and after the weaving is completed, a temperature treatment is performed at 550°C for 120 minutes to prepare an alumina fiber static sealing material, thereby obtaining a flexible, high-temperature, and infrared-resistant alumina fiber static sealing material.

[0057] Product performance test: The static sealing material prepared by the above method has a cross-sectional size of 10mm*14mm. After being treated at 1500℃ for 30min, the dimensional shrinkage rate is ≤2%, the minimum flexible bending radius can reach 3cm, and the room temperature thermal conductivity is 0.039W / (Km).

[0058] Parts of the present invention that are not described in detail are well known to those skilled in the art.

[0059] Although the present invention has been disclosed as above by way of embodiments, it is not intended to limit the present invention. Appropriate modifications or equivalent substitutions of the technical solutions of the present invention made by ordinary technicians in the field should all be included in the protection scope of the present invention. The protection scope of the present invention shall be based on what is defined in the claims.

Claims

1. A method for preparing a high temperature resistant and infrared radiation resistant alumina fiber static sealing material, characterized in that: The steps include: (1) twisting alumina fibers to control the twist and prepare alumina twisted yarns; (2) plying a plurality of the alumina twisted yarns to prepare alumina twisted plied yarns; (3) preparing nano-alumina ceramic powder, a light shielding agent component, a binder and a diluent in a mass ratio of (1-5):(1-8):(0.5-10):100, stirring evenly, and preparing a composite impregnation solution; (4) using the composite impregnation liquid to impregnate and composite the alumina twisted plied yarn, and then drying it, and after drying, an alumina composite wire is obtained; (5) Using the alumina composite wire according to different weaving methods and weaving cross-sectional shapes, adjusting the weaving volume fraction, performing online weaving, and performing a heating treatment after weaving to prepare an alumina fiber static sealing material.

2. The method according to claim 1, characterized in that The tex number of the alumina fiber ranges from 60 to 600 tex; the twist ranges from 10 to 180 twists / m.

3. The method according to claim 1, characterized in that The number of the combined shares is 2 to 10.

4. The method according to claim 1, characterized in that The sunscreen component is one, two or three of chromium oxide, silicon carbide, nickel oxide, iron oxide, manganese dioxide, lanthanum oxide and titanium dioxide; the adhesive is one of silica sol and silicone resin; the diluent is one of ethanol and acetone.

5. The method according to claim 1, characterized in that The impregnation composite method is a one-step production method of the alumina twisted plied yarn by continuous online impregnation, drying and winding.

6. The method according to claim 1, characterized in that The drying method is hot air circulation heating drying; the drying temperature is 60-150°C.

7. The method according to claim 1, characterized in that The weaving method is one of two-dimensional three-directional, three-dimensional four-directional, and three-dimensional five-directional; the weaving cross-sectional shape is one of circular and rectangular.

8. The method according to claim 1, characterized in that The braiding volume fraction is 30% to 50%.

9. The method according to claim 1, characterized in that The temperature of the heating treatment is 500-600° C., and the time of the heating treatment is 10-120 minutes.

10. A high temperature resistant and infrared radiation resistant alumina fiber static sealing material, characterized in that: The method is prepared by any one of claims 1 to 9.

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