A broad-spectrum anticorrosive, expansion-controlled, wear-resistant, heat-conductive polytetrafluoroethylene-based composite profile and a method for preparing the same

Abstract

This invention discloses a broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene (PTFE) composite profile and its preparation method. The composite profile is formed by stacking multiple PTFE wear-resistant and thermally conductive elements (3), at least one PFA welding element (5), and at least one carbon fiber expansion control element (7) along the thickness direction. The PTFE wear-resistant and thermally conductive element consists of two layers of polytetrafluoroethylene film (1) and a first wear-resistant and thermally conductive coating (2) applied alternately to the two layers of polytetrafluoroethylene film. The PFA welding element consists of two layers of PFA film (4) and a second wear-resistant and thermally conductive coating (2) applied alternately to the two layers of PFA film. The carbon fiber expansion control element consists of a layer of carbon fiber fabric (6) and a third wear-resistant and thermally conductive coating (2) applied to the carbon fiber fabric. The composite profile of this invention has good welding performance, high high-temperature strength, good wear resistance, strong thermal conductivity, and low expansion coefficient and creep. It expands the application range of PTFE-based materials to all acid and alkali corrosion resistance, wear resistance, and thermal conductivity conditions, providing a reliable material basis for complex chemical and metallurgical processes.

Description

Technical Field

[0001] This invention belongs to the technical field of corrosion-resistant, wear-resistant, and thermally conductive materials, specifically relating to a broad-spectrum corrosion-resistant, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile and its preparation method. Background Technology

[0002] In industrial production processes such as metallurgy and chemical engineering, various corrosion and wear resistance problems are frequently encountered. With the gradual depletion of non-renewable resources, engineers are facing the challenge of recycling low-grade, complex mixed resources, requiring the design of more complex production processes. This leads to more complex corrosion, wear, and heat exchange conditions, such as corrosion and wear resistance in mixed acids under high temperature and pressure, high-temperature alternating acid and alkali resistance, and indirect heating under high-temperature, high-pressure, and highly corrosive conditions. Currently available anti-corrosion materials are insufficient to meet these stringent requirements on their own.

[0003] Polytetrafluoroethylene (PTFE) and its modified materials are considered the most promising materials for solving the aforementioned problems due to their excellent corrosion resistance. However, PTFE materials also have significant drawbacks that severely limit their application areas: for example, PTFE has poor thermal conductivity, making it unsuitable as an indirect heating corrosion-resistant lining; under high-temperature conditions, PTFE's wear resistance deteriorates, making it unsuitable for prolonged use in environments with strong abrasion; its strength decreases, making it unsuitable for use under strong negative pressure; PTFE has a large coefficient of thermal expansion, and disordered expansion at high temperatures often leads to localized bulging, severely affecting its service life. Furthermore, PTFE materials have poor weldability (relying on bonding rather than fusion), and the stress generated during high-temperature expansion is mainly concentrated at the weld, making the weld the most vulnerable point for PTFE linings, severely limiting its safe operating temperature and safety. Although there are products on the market that add thermally conductive materials, wear-resistant materials or fiber materials to PTFE materials to improve their performance, there is no product that can simultaneously possess comprehensive properties such as high wear resistance, high thermal conductivity, low expansion, low creep and welding safety. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile and its preparation method, which has good weldability, high high-temperature strength, good wear resistance, strong thermal conductivity, and significantly reduced expansion coefficient and creep.

[0005] The technical solution adopted in this invention is as follows: A broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile, wherein the composite profile is composed of multiple PTFE wear-resistant and thermally conductive units, at least one PFA welding unit, and at least one carbon fiber expansion-controlled unit stacked along the thickness direction. The PTFE wear-resistant and thermally conductive unit consists of two layers of polytetrafluoroethylene film and a first wear-resistant and thermally conductive coating applied between the two layers of polytetrafluoroethylene film. The PFA welding unit consists of two layers of PFA film and a second wear-resistant and thermally conductive coating applied between the two layers of PFA film. The carbon fiber expansion control unit consists of a layer of carbon fiber fabric and a third wear-resistant and thermally conductive coating applied to the carbon fiber fabric.

[0006] Furthermore, the number and order of the stacked layers of the PTFE wear-resistant and thermally conductive unit, the PFA welding unit, and the carbon fiber expansion control unit are determined according to the operating conditions of the material; the PFA welding unit is at least located at the upper or lower part of the composite profile in the thickness direction.

[0007] Furthermore, the thickness of the polytetrafluoroethylene film and / or PFA film is greater than or equal to 0.01 mm.

[0008] Furthermore, the first wear-resistant thermal conductive coating, the second wear-resistant thermal conductive coating, and the third wear-resistant thermal conductive coating are all perfluoroalkoxy resin-based coatings or Teflon coatings containing wear-resistant thermal conductive powder; the wear-resistant thermal conductive powder is selected from one or more of diamond powder, silicon carbide powder, graphite powder, graphene powder, and coke powder.

[0009] Furthermore, the raw materials for the perfluoroalkoxy resin-based coating consist of toluene, wear-resistant and thermally conductive powder, and perfluoroalkoxy resin powder, preferably in a weight ratio of 2:2:1. Furthermore, the carbon fiber fabric is a carbon fiber cloth, carbon fiber tape, or carbon fiber filament that has been pre-impregnated with a perfluoroalkoxy resin coating or a Teflon coating.

[0010] This invention also provides a method for producing the aforementioned broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile, comprising the following steps: S1. Blank preparation: On the molding die, PTFE wear-resistant and heat-conducting elements, PFA welding elements and carbon fiber expansion control elements are laid alternately from the inside to the outside or from the bottom to the top. After reaching the predetermined thickness, a high-temperature resistant glass fiber layer is wrapped on the outermost layer to complete the blank preparation. S2. High-temperature firing: The green body obtained in step S1 is sent into a constant temperature firing furnace for firing at a temperature of 300-380℃. S3. Post-processing: After firing, allow the material to cool naturally, remove the outer layer of glass fiber, demold, and the composite profile is obtained.

[0011] Furthermore, the carbon fiber fabric described in step S1 of the present invention is first fully soaked in perfluoroalkoxy resin coating or Teflon coating before use, and then cooled to semi-dry before use.

[0012] Furthermore, the PTFE wear-resistant and thermally conductive element, PFA welding element, and carbon fiber expansion control element of the present invention are stacked on the mandrel by coating or winding to obtain a composite pipe blank.

[0013] Furthermore, the molding mold mentioned in step S1 of the present invention is a plate mold, including a bottom mold and a top mold. After the last layer of PTFE film is laid, a layer of high temperature resistant glass fiber cloth is laid first, and then the top mold is pressed on and pressed with an elastic element to obtain a composite plate blank.

[0014] The beneficial effects of this invention are: 1. This invention uses PTFE film as a substrate to give the composite profile broad-spectrum anti-corrosion properties, avoiding the problem of the anti-corrosion layer penetrating when using PTFE powder; 2. The thinner the PTFE film layer of the present invention, the more wear-resistant and thermally conductive powder is introduced, the better the wear-resistant and thermally conductive performance of the composite profile, the lower the expansion coefficient, and the smaller the creep. The PFA coating coats the powder particles, making their bonding strength with the PTFE film greater, their penetration resistance better, and their wear resistance better. 3. The uniformly arranged carbon fiber fabric of the present invention transforms the disordered expansion of PTFE into uniform and ordered expansion, restricts the expansion in each direction, and the carbon fiber fabric impregnated with PFA bonds firmly to the PTFE film, thereby improving the high-temperature strength of the composite profile. 4. The arrangement of the PFA film layer in this invention allows the PFA material of the welding rod to melt together with the PFA material in the composite profile during welding, increasing the welding strength and solving the problem of weak welds in traditional PTFE materials. 5. The composite profile of the present invention expands the application range of PTFE-based materials to all acid and alkali corrosion resistance, wear resistance and heat conduction conditions, providing a reliable material basis for complex chemical and metallurgical processes. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the PTFE wear-resistant and thermally conductive element in this invention; Figure 2 This is a schematic diagram of the structure of the PFA welding element in this invention; Figure 3 This is a schematic diagram of the structure of the carbon fiber expansion control unit in this invention; Figure 4 This is a schematic diagram illustrating the fabrication of a composite pipe structure according to Embodiment 1 of the present invention; Figure 5 This is a schematic diagram illustrating the fabrication of a composite structure of the composite board in Embodiment 2 of the present invention.

[0016] In the figure: 1. Polytetrafluoroethylene film; 2. Wear-resistant and thermally conductive coating; 3. PTFE wear-resistant and thermally conductive element; 4. PFA film; 5. PFA welding element; 6. Carbon fiber fabric; 7. Carbon fiber expansion control element; 8. Core mold; 9. Glass fiber layer; 10. Bottom mold; 11. Top mold; 12. Elastic element. Detailed Implementation

[0017] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0018] like Figures 1-3 As shown, the present invention provides a broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile, wherein the composite profile is formed by stacking multiple PTFE wear-resistant and thermally conductive units 3, at least one PFA welding unit 5, and at least one carbon fiber expansion-controlled unit 7 along the thickness direction. The PTFE wear-resistant and thermally conductive unit consists of two layers of polytetrafluoroethylene film 1 and a first wear-resistant and thermally conductive coating 2 coated on the two layers of polytetrafluoroethylene film at intervals. By introducing the wear-resistant and thermally conductive coating between the PTFE films, the corrosion-resistant and airtight properties of PTFE are ensured while introducing as much material as possible with low expansion coefficient, high hardness, and high thermal conductivity. The thinner the PTFE and the more layers there are, the more wear-resistant and thermally conductive powder is introduced, and the better the performance of the composite profile. The PFA welding unit consists of two layers of PFA film 4 and a second wear-resistant and thermally conductive coating 2 applied between the two layers of PFA film. This unit is used to enhance the welding performance of the material. The thinner the PTFE film, the easier it is to be pierced by high-hardness powder particles during the firing process, resulting in discontinuity of the PTFE material and affecting the corrosion resistance of the material. Therefore, the wear-resistant and thermally conductive powder particles are coated with PFA coating. During high-temperature firing, the PFA liquid can fill all possible PTFE film pores, ensuring the sealing of the composite profile. At the same time, PFA also makes the powder particles adhere more firmly to the PTFE film, thereby improving the wear resistance of the material. When welding the composite profile, the PFA in the material on both sides of the weld will melt into one with the PFA solder, thereby greatly improving the safety of the weld. The number and order of the stacked layers of the PTFE wear-resistant and thermally conductive unit 3, PFA welding unit 5, and carbon fiber expansion control unit 7 are determined according to the material's operating conditions. The PFA welding unit 5 is at least located at the upper or lower part of the composite profile's thickness direction. Introducing two layers of welding substrate composed of PFA film and wear-resistant and thermally conductive powder into the upper and lower parts of the composite profile can improve the material's welding performance. PTFE material welding relies on PFA solder to bond the two sides of PTFE together. Its strength is mainly positively correlated with the bonding area. The weld is the vulnerable point of a large-area PTFE anti-corrosion layer. The introduction of the PFA layer allows the PFA solder to fuse with the PFA in the material interlayer, greatly increasing the welding strength and improving the weld safety. The thickness of the polytetrafluoroethylene film 1 and / or PFA film 4 is greater than or equal to 0.01 mm, and can be a sheet, strip or other form of film.

[0019] The first, second, and third wear-resistant thermally conductive coatings are all perfluoroalkoxy resin-based coatings or Teflon coatings containing wear-resistant thermally conductive powder. The wear-resistant thermally conductive powder is selected from one or more of diamond powder, silicon carbide powder, graphite powder, graphene powder, and coke powder. The wear-resistant thermally conductive powder can be selected according to the application conditions of the material. If the main function is thermal conductivity, graphene or graphite powder can be selected; if the main function is wear resistance and alkali resistance is not required, silicon carbide powder can be selected; if acid and alkali resistance are required, and wear resistance and thermal conductivity are also required, then only diamond powder can be selected. The raw materials for the perfluoroalkoxy resin-based coating consist of toluene, wear-resistant and thermally conductive powder, and perfluoroalkoxy resin powder, with a preferred ratio of 2:2:1 by weight. This ratio enables the coating to achieve optimal coating and adhesion performance. The carbon fiber expansion control unit 7 consists of a layer of carbon fiber fabric 6 and a third wear-resistant and thermally conductive coating 2 applied to the carbon fiber fabric 6. This unit is used to control the thermal expansion of the material and improve its strength. One or more layers of carbon fiber fabric are uniformly arranged in the composite profile to control the orderly expansion of the PTFE material, preventing disordered expansion from causing local swelling and damage, and improving the high-temperature strength of the composite profile. The carbon fiber fabric is carbon fiber cloth, carbon fiber tape, or carbon fiber filament that has been fully impregnated with perfluoroalkoxy resin coating or Teflon coating. The impregnated carbon fiber fabric has greater tensile strength and better performance. The more layers of carbon fiber fabric, the better the effect. A wear-resistant and thermally conductive layer is applied to the carbon fiber to further enhance its wear resistance and thermal conductivity. This carbon fiber expansion control unit controls the uniform and orderly expansion of the PTFE material, preventing disordered expansion from causing local swelling and damage. The wear-resistant and thermally conductive coating 2 in each of the above basic components is formed by applying a PFA-based coating containing wear-resistant and thermally conductive powder. The carbon fiber fabric 6 is preferably pre-impregnated with PFA coating before use. The wear-resistant and thermally conductive powder may not be added to the PFA coating used for impregnation in order to reduce costs.

[0020] The number and order of the stacked layers of the PTFE wear-resistant thermally conductive unit 3, PFA welding unit 5, and carbon fiber expansion control unit 7 described in this invention are determined according to the material's operating conditions. The PFA welding unit 5 is at least disposed in the upper and lower parts of the composite profile in the thickness direction. In one embodiment, the stacking scheme is as follows: first, multiple PTFE wear-resistant thermally conductive units are stacked, then one PFA welding unit is stacked, then one or more PTFE wear-resistant thermally conductive units are stacked, then one carbon fiber expansion control unit is stacked, then 3-8 layers of PTFE wear-resistant thermally conductive units are stacked, then one carbon fiber expansion control unit is stacked, then 1-3 layers of PTFE wear-resistant thermally conductive units are stacked, then one PFA welding unit is stacked, and finally one layer of PTFE wear-resistant thermally conductive unit is stacked. Preferably, the PFA welding unit is disposed in the upper and lower parts of the composite profile in the thickness direction. When the total material thickness is less than 1 mm, the PFA welding unit may be disposed only once.

[0021] The present invention also provides a method for preparing the above-mentioned composite profile, comprising the following steps: S1. Preform preparation: On the molding die, PTFE wear-resistant and heat-conducting elements, PFA welding elements, and carbon fiber expansion control elements are alternately laid from the inside out or from the bottom up until a predetermined thickness is reached. Then, a high-temperature resistant glass fiber layer is wrapped on the outermost layer to complete the preform preparation. The carbon fiber fabric can be fully soaked in perfluoroalkoxy resin coating or Teflon coating before use and then cooled to semi-dry. S2. High-temperature firing: The green body obtained in step S1 is sent into a constant temperature firing furnace for firing at a firing temperature of 300°C to 380°C. The final firing temperature is adjusted according to the specific material of the substrate and the thickness of the green body. S3. Post-processing: After firing, allow the material to cool naturally, remove the outer layer of glass fiber, demold, and the composite profile is obtained.

[0022] Specifically, when preparing pipes, the forming mold mentioned in step S1 is a pipe core mold, and each basic element is stacked on the core mold by wrapping or winding. When preparing sheets, the forming mold mentioned in step S1 is a sheet mold, including a bottom mold and a top mold. After laying the last layer of PTFE film, a layer of high-temperature resistant glass fiber cloth is first laid, and then the top mold is pressed on and tightened with elastic elements (such as spring-loaded screws). Example 1

[0023] In this embodiment, a wear-resistant thermally conductive composite tube with a diameter of 100×2×3000mm is fabricated. I. Technical Requirements and Material Selection 1. Operating conditions: The outside of the tube contains a liquid slurry mixture of hydrochloric acid and hydrofluoric acid with a solid content of ≤50g / L and a temperature of 90°C; the inside of the tube contains a gas-liquid mixture of hydrochloric acid and hydrofluoric acid with a solid content of 10g / L and a temperature of 150°C.

[0024] 2. Material selection: Substrate: PTFE tape with a thickness of 50×0.1mm; Powder: 800 mesh silicon carbide powder, 200 mesh graphene powder; Carbon fiber: Carbon fiber tape with a thickness of 50×0.2mm; Fiberglass: 50×0.5mm high-temperature resistant fiberglass tape; Mold: Stainless steel combination core mold with a diameter of 98mm × 2 × 3500mm; Wear-resistant and thermally conductive coating: It is prepared by mixing toluene, silicon carbide powder and PFA powder in a dry weight ratio of 2:2:1.

[0025] II. Preparation steps are as follows Figure 4 As shown: Green body preparation: 1. Wrap a layer of PTFE film around the core mold 8, with an overlap width of 5-8mm. 2. Apply a layer of wear-resistant and thermally conductive coating, thickness: 0.04-0.06mm; 3. Wrap a 0.1 mm thick PTFE film, then apply a layer of coating, repeating three times; 4. Wrap a layer of PFA film on the fourth coating layer, with a film thickness of 0.1 mm and an overlap width of 5-8 mm; 5. Apply a coating consisting of toluene and silicon carbide powder, 0.04-0.06 mm thick, onto the PFA film; 6. Wrap a layer of PFA film, 0.1 mm thick, with an overlap of 5-8 mm, over the fifth coating layer; 7. Apply a 0.04-0.06mm thick layer of wear-resistant and thermally conductive coating, then wrap a 0.1mm thick PTFE film around it. Repeat this process twice. 8. Wrap a layer of carbon fiber tape, 0.2mm thick, with an overlap of 5-8mm, onto the ninth layer of PTFE film. The carbon fiber tape is pre-impregnated with toluene and PFA powder coating, and wound while semi-dry. 9. Apply a layer of wear-resistant and thermally conductive coating, 0.04-0.06mm thick, to the carbon fiber strip; 10. Repeat step 3 twice more; 11. Wrap a layer of PFA film around the eleventh layer of coating, using the same method as in step 4; 12. Repeat steps 5, 6, 7, 8, and 9; 13. Repeat step 3 until a thickness of 2 mm is achieved. 14. Wrap a layer of fiberglass tape 9, with an overlap width of 8-10mm; High-temperature firing: The blank is placed in a constant temperature furnace for firing, with the firing temperature controlled at 360-370℃ and held for 30-60 minutes.

[0026] Post-processing: After natural cooling to room temperature, remove the outer glass fiber tape, take out the core mold, and you will get the desired composite pipe.

[0027] Tests have shown that the pipes prepared using the above method fully meet the predetermined operating conditions and have a service life of more than 5 years. Example 2

[0028] In this embodiment, a wear-resistant and thermally conductive composite plate measuring 1000×2000×2mm is fabricated. I. Material Selection (Same as Example 1) II. Preparation steps are as follows Figure 5 As shown: Green body preparation: 1. Lay a layer of fiberglass cloth with a thickness of 0.5-1mm on the 1100x2100 mm bottom mold 10; 2. Lay a layer of PTFE film with a thickness of 0.1 mm on the fiberglass cloth; 3. Apply a layer of wear-resistant and thermally conductive coating to the PTFE film, with a thickness of 0.04~0.06mm. The wear-resistant and thermally conductive coating is composed of toluene, silicon carbide fine powder, and PFA fine powder in a weight ratio of 2:2:1. Then, lay another layer of PTFE film. Repeat this process three times. Finally, apply another layer of wear-resistant and thermally conductive coating to the fourth layer of PTFE film, using the same method and thickness. 4. Lay a PFA film with a thickness of 0.1 mm on the fourth coating layer, then brush on a coating layer with a thickness of 0.04-0.06 mm; then lay another PFA film with a thickness of 0.1 mm; then brush on another coating layer with the same thickness. 5. Lay a PTFE film on the sixth coating layer, and then brush on another coating layer, with the same thickness and method as in step 3; repeat this process twice. 6. Lay a layer of carbon fiber cloth with a thickness of 0.2 mm on the eighth layer of coating; the carbon fiber cloth is pre-impregnated with a coating composed of toluene and PFA powder, and laid after it has cooled to semi-dry; then brush on a layer of wear-resistant and thermally conductive coating, and then lay a layer of PTFE film, with the same material and thickness as before; 7. Repeat steps 3-6; 8. Repeat step 5 until a thickness of 2 mm is achieved; 9. Lay a final layer of PTFE film on the final coating layer, followed by a layer of fiberglass cloth, with the same material and thickness as above; 10. Press down the top mold 11, and use the spring-loaded screw 12 to tighten the upper and lower molds. Screw pressure: 0.25 MPa; High-temperature firing: The blank, along with the mold, is sent into a constant-temperature furnace for firing, with the firing temperature controlled at 360-370℃.

[0029] Post-processing: After natural cooling, remove the upper and lower templates and remove the fiberglass cloth to obtain the desired composite board.

[0030] Tests have shown that the composite board prepared by the above method has more than twice the thermal conductivity and wear resistance of a pure PTFE board of the same thickness.

[0031] The above embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A broad-spectrum, corrosion-resistant, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile, characterized in that, The composite profile is formed by stacking multiple PTFE wear-resistant and thermally conductive elements (3), at least one PFA welding element (5), and at least one carbon fiber expansion control element (7) along the thickness direction. The PTFE wear-resistant and thermally conductive unit consists of two layers of polytetrafluoroethylene film (1) and a first wear-resistant and thermally conductive coating (2) applied between the two layers of polytetrafluoroethylene film; The PFA welding unit consists of two layers of PFA film (4) and a second wear-resistant and thermally conductive coating (2) applied between the two layers of PFA film; The carbon fiber expansion control unit consists of a layer of carbon fiber fabric (6) and a third wear-resistant and thermally conductive coating (2) applied to the carbon fiber fabric.

2. The broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile according to claim 1, characterized in that, The number and order of the stacked layers of the PTFE wear-resistant and thermally conductive unit, the PFA welding unit, and the carbon fiber expansion control unit are determined according to the operating conditions of the material; the PFA welding unit is at least located at the upper or lower part of the composite profile in the thickness direction.

3. The broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile according to claim 1, characterized in that, The thickness of the polytetrafluoroethylene film and / or PFA film is greater than or equal to 0.01 mm.

4. The broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile according to claim 1, characterized in that, The first wear-resistant thermal conductive coating, the second wear-resistant thermal conductive coating, and the third wear-resistant thermal conductive coating are all perfluoroalkoxy resin-based coatings or Teflon coatings containing wear-resistant thermal conductive powder; the wear-resistant thermal conductive powder is selected from one or more of diamond powder, silicon carbide powder, graphite powder, graphene powder, and coke powder.

5. The broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile according to claim 4, characterized in that, The raw materials for the perfluoroalkoxy resin-based coating consist of toluene, wear-resistant and thermally conductive powder, and perfluoroalkoxy resin powder, with a preferred weight ratio of 2:2:

1.

6. The broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile according to claim 1, characterized in that, The carbon fiber fabric is a carbon fiber cloth, carbon fiber tape, or carbon fiber filament that has been pre-impregnated with a perfluoroalkoxy resin coating or a Teflon coating.

7. A method for preparing the broad-spectrum anti-corrosion, expansion-controlled, wear-resistant, and thermally conductive polytetrafluoroethylene composite profile as described in any one of claims 1-6, characterized in that, Includes the following steps: S1. Blank preparation: On the molding die, PTFE wear-resistant and heat-conducting elements, PFA welding elements and carbon fiber expansion control elements are laid alternately from the inside to the outside or from the bottom to the top. After reaching the predetermined thickness, a high-temperature resistant glass fiber layer is wrapped on the outermost layer to complete the blank preparation. S2. High-temperature firing: The green body obtained in step S1 is sent into a constant temperature firing furnace for firing at a temperature of 300-380℃. S3. Post-processing: After firing, allow the material to cool naturally, remove the outer layer of glass fiber, demold, and the composite profile is obtained.

8. The preparation method according to claim 7, characterized in that, The carbon fiber fabric described in step S1 should be fully soaked in perfluoroalkoxy resin coating or Teflon coating before use, and then cooled to semi-dry before use.

9. The preparation method according to claim 7, characterized in that, The molding die mentioned in step S1 is a pipe core mold. The PTFE wear-resistant and heat-conducting unit, PFA welding unit and carbon fiber expansion control unit are stacked on the core mold by wrapping or winding to obtain a composite pipe blank.

10. The preparation method according to claim 7, characterized in that, The molding mold mentioned in step S1 is a sheet mold, including a bottom mold and a top mold. After laying the last layer of PTFE film, a layer of high-temperature resistant glass fiber cloth is laid first, and then the top mold is pressed on and pressed with elastic elements to obtain a composite sheet blank.

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