Self-lubricating bearing gasket modified and enhanced by Ag nanoparticles and preparation method of self-lubricating bearing gasket

Abstract

The invention discloses a preparation method of a self-lubricating bearing gasket modified and enhanced by Ag nanoparticles. The preparation method comprises the following steps: S1, modifying the surface of a fabric to form active reaction sites on the surface of the fabric to obtain a sensitized fabric; s2, metal silver ions and organic ligands are dissolved in an organic solvent, the solvent is stirred under the light-free condition so that the metal silver ions and the organic ligands can be evenly mixed to obtain a metal mixture, and the metal mixture and the sensitized fabric are transferred into a reactor with a polytetrafluoroethylene lining to be heated for several hours so as to modify the fabric; and S3, putting the modified fabric into a tubular furnace, and carrying out high-temperature reduction treatment on the modified fabric in a nitrogen atmosphere, so that a compact metal silver layer is generated on the surface of the modified fabric to obtain the nano metal particle modified fabric. The liner provided by the invention has excellent mechanical properties, wear resistance, heat resistance, corrosion resistance, self-lubricating property, uniformity, compactness and high thermal conductivity, and is suitable for being used as a self-lubricating liner of a sliding bearing.

Description

Technical Field

[0001] The invention belongs to the field of self-lubricating composite materials, and in particular relates to a self-lubricating bearing liner modified and enhanced with Ag nanoparticles and a preparation method thereof. Background Art

[0002] As a sliding bearing, spherical plain bearings have a relatively simple structural design, primarily consisting of an outer ring and an inner ring. The outer ring has a spherical inner surface, while the inner ring has a spherical outer surface. Self-lubricating spherical plain bearings offer innovative improvements on this basis, achieving significant performance improvements by embedding or bonding a self-lubricating liner between the inner and outer rings. This self-lubricating liner is a core element of spherical plain bearings, enabling their widespread use in high-tech fields such as aerospace and aviation, where they demonstrate key performance indicators such as excellent load capacity, impact resistance, and long life.

[0003] Fabric-based self-lubricating spherical plain bearings play an important role in civil aerospace and aircraft landing gear, brake pads, self-lubricating bearings, and engine high-thermal conductivity sealing systems due to their simple structure, maintenance-free operation, and the need for added lubricants. However, there is still a large gap between domestically produced fabric self-lubricating spherical plain bearings and advanced foreign technologies. The low service life of aerospace self-lubricating bearings increases replacement costs, and frequent maintenance can reduce the response speed of aircraft. With the development of high Mach numbers in my country's aviation equipment, the service conditions of self-lubricating spherical plain bearings are becoming increasingly demanding, placing higher demands on their service life and lightweighting.

[0004] Common fiber fabric pads are woven with high-performance aramid fiber and polytetrafluoroethylene fiber as raw materials, and then dipped in glue to shape them. The resin in the dipping solution is used to bond the fabric together to improve wear resistance and load-bearing capacity. Among them, polytetrafluoroethylene fiber plays a lubricating role, and high-performance aramid fiber plays a skeleton reinforcement role.

[0005] Currently, research on fabric-based self-lubricating bearing liners focuses primarily on fabric structure, fiber reinforcement properties, resin matrix, functional enhancement fillers, and fiber surface modification. Introducing highly thermally conductive fillers into the liner is the most common solution for improving thermal conductivity. However, increasing the filler loading significantly increases the liner's cost and density, and significantly reduces its mechanical properties. Summary of the Invention

[0006] In order to solve the above problems existing in the prior art, the present invention provides a self-lubricating bearing liner modified and enhanced with Ag nanoparticles and a preparation method thereof. The technical problem to be solved by the present invention is achieved through the following technical solutions: A method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles, comprising: S1. Modifying the surface of the fabric to form active reaction sites on the fabric surface to obtain a sensitized fabric; S2, dissolving metallic silver ions and organic ligands in an organic solvent, stirring the solvent in the absence of light to uniformly mix the metallic silver ions and the organic ligands to obtain a metal mixture, transferring the metal mixture and the sensitized fabric into a polytetrafluoroethylene-lined reactor and heating for several hours to modify the fabric; S3. Putting the modified fabric into a tube furnace and subjecting the modified fabric to high-temperature reduction treatment in a nitrogen atmosphere to form a dense metallic silver layer on the surface of the modified fabric to obtain nano-metal particle modified fabric.

[0007] In one embodiment, the fabric comprises a blended fabric of reinforcing phase fibers and lubricating phase fibers.

[0008] In one embodiment, the fabric has an area density of 200-500 g / m 2 , fiber fineness is 300D-1200 D, thickness is 0.25 -0.50 mm.

[0009] In a specific embodiment, the step S1 specifically includes: The fabric was ultrasonically cleaned using acetone and ethanol; The ultrasonically cleaned fabric is immersed in a sensitizer for modification to construct active reaction sites to obtain a sensitized fabric.

[0010] In a specific embodiment, the sensitizer is a tannic acid solution, which includes a tannic acid body and a mixed solvent, the mixed solvent is an ethanol aqueous solution, and the mass ratio of the tannic acid body to the ethanol aqueous solution is (0.05~0.2):1.

[0011] In a specific embodiment, the organic ligand is terephthalic acid, and the molar ratio of the metal silver ion to the organic ligand is (1-3):1.

[0012] In a specific embodiment, the step S3 further includes: S4, immersing the nano-metal particle modified fabric in a phenolic resin dilution solution, repeatedly immersing and roller-drying until the mass fraction of the phenolic resin is at least 15% to obtain a nano-metal particle modified fabric with phenolic resin; S5. Performing a hot pressing process on the nano-metal particle modified fabric with phenolic resin to obtain a nano-metal particle modified fabric pad.

[0013] The present invention also provides a self-lubricating bearing liner modified and enhanced by Ag nanoparticles, comprising: a fiber fabric and an impregnating resin loaded on the fiber fabric, wherein the surface of the fiber fabric has a dense metallic silver layer.

[0014] In one embodiment, the fabric comprises a blended fabric of reinforcing phase fibers and lubricating phase fibers, and the surface density of the fabric is 200-500 g / m 2 , fiber fineness is 300 D-1200 D, thickness is 0.25 -0.50 mm.

[0015] In a specific embodiment, the impregnating resin is a phenolic resin, and the mass ratio of the impregnating resin is 15-35%.

[0016] Beneficial effects of the present invention: 1. The present invention provides a self-lubricating bearing pad modified and reinforced with Ag nanoparticles. It utilizes the continuous mesh structure of the three-dimensional orthogonal fabric to construct a strong bearing layer. By interweaving aramid fibers and PTFE fibers between layers, the interlayer bonding force is enhanced. The Z-direction reinforcing fibers are introduced to improve the overall shear resistance and anti-delamination performance. This overcomes the shortcomings of traditional two-dimensional laminated composite materials, such as poor impact resistance, low interlayer strength, and easy delamination. The three-dimensional aramid / PTFE fabric has a continuous heat conduction channel in the thickness direction, achieving high thermal conductivity of the fabric-based self-lubricating bearing pad, thereby solving the serious heat accumulation and wear problems caused by high friction heat of the friction pair under harsh conditions of high temperature, high load, and high speed. 2. The present invention provides a self-lubricating bearing pad modified and reinforced with Ag nanoparticles. By in-situ self-assembling a metal layer on the surface of the three-dimensional aramid / PTFE fabric, a strong metal layer is constructed, providing an important fiber material for high-performance self-lubricating bearings, and achieving controllable thermal conductivity and lubrication performance of the fabric pad. In addition, resin impregnation of fiber fabrics with metal layers on their surfaces effectively ensures that the metal layer continuously and stably generates heat and cools the surface during friction. This preparation method is characterized by simplicity, low cost, and high practicality. 3. The present invention provides a self-lubricating bearing liner modified and reinforced with Ag nanoparticles, which exhibits excellent mechanical properties, wear resistance, heat resistance, corrosion resistance, self-lubrication, uniformity, compactness, and high thermal conductivity, making it suitable for use as a self-lubricating liner for sliding bearings.

[0017] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic flow chart of a method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles provided by an embodiment of the present invention; Figure 2a This is the SEM image before in-situ growth of Ag nanoparticles on the fiber surface; Figure 2b This is the SEM image of the fiber surface after in-situ growth of Ag nanoparticles; Figure 3a This is the SEM image of the wear scar after the friction test of Comparative Example 1; Figure 3b This is the SEM image of the wear scar after the friction test in Example 4. DETAILED DESCRIPTION

[0019] The present invention will be further described in detail below with reference to specific examples, but the embodiments of the present invention are not limited thereto.

[0020] Example 1 See Figure 1 , Figure 1 The present invention provides a schematic flow chart of a method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles, including: S1. Modifying the surface of the fabric to form active reaction sites on the fabric surface to obtain a sensitized fabric; Specifically, the fabric may be, for example, a two-dimensional or three-dimensional mixed fiber fabric, the mixed fiber fabric comprising reinforcing fibers and lubricating fibers. The reinforcing fibers may be aramid fibers, basalt fibers, etc., and the lubricating fibers may be PTFE fibers, etc., for example, a mixed aramid / PTFE fabric. Preferably, the surface density of the mixed fiber fabric is 200-500 g / m 2 The fiber fineness is 300 D-1200 D and the thickness is 0.25-0.50 mm. When the mixed fiber fabric is a mixed aramid / PTFE fabric, it can be a three-way orthogonal, 2.5D or three-dimensional woven fabric.

[0021] In a specific embodiment, step S1 specifically includes: The fabric is ultrasonically cleaned using acetone and ethanol; preferably, the ultrasonic cleaning time for acetone and ethanol cleaning is 3-6 h, respectively.

[0022] The ultrasonically cleaned fabric is immersed in a sensitizer for modification to construct active reaction sites to obtain a sensitized fabric.

[0023] Preferably, the sensitizer is a tannic acid solution, which includes a tannic acid body and a mixed solvent, the mixed solvent is an ethanol aqueous solution, and the mass ratio of the tannic acid body to the ethanol aqueous solution is (0.05~0.2):1.

[0024] S2, dissolving the metallic silver ion and the organic ligand in an organic solvent, and stirring the solvent in the absence of light to uniformly mix the metallic silver ion and the organic ligand to obtain a metal mixture, transferring the metal mixture and the sensitized fabric to a polytetrafluoroethylene-lined reactor and heating for several hours to modify the fabric; the organic ligand is terephthalic acid, the metallic silver ion and the organic ligand molar ratio is (1-3): 1, and the immersion stirring time is 1-3 h. The no-light condition is a dark environment with light shielding. Specifically, it is necessary to heat at 140 ° C for 10 h, wash the product twice and put it into an oven and dry it at 60 ° C for 2-8 h. And sinter in a tube furnace at 280 ° C for 2 h. Preferably, the metallic silver ion and the organic ligand molar ratio is (1.8-2.2): 1.

[0025] S3. Putting the modified fabric into a tube furnace and subjecting the modified fabric to high-temperature reduction treatment in a nitrogen atmosphere to form a dense metallic silver layer on the surface of the modified fabric to obtain nano-metal particle modified fabric.

[0026] In a specific embodiment, the step S3 further includes: S4, immersing the nano-metal particle modified fabric in a phenolic resin dilution solution, repeatedly immersing and roller-drying until the mass fraction of the phenolic resin is at least 15% to obtain a nano-metal particle modified fabric with phenolic resin; Specifically, the impregnation process is: placing the nano-metal particle modified fabric in an impregnation solution containing an impregnation resin and performing ultrasonic treatment; The ultrasonically treated nano-metal particle modified fabric is rolled under a roller for several times to remove the bubbles generated during the impregnation process; The nano-metal particle modified fabric with resin and after rolling to remove bubbles is placed in an oven for drying. Preferably, the mass content of the impregnating resin is 15-35%, and the diluent is a mixture of ethanol and ethyl acetate = 1:1.

[0027] The ultrasonic treatment, roller pressing and drying were repeated as a cycle 4 to 6 times.

[0028] Preferably, each ultrasonic treatment lasts 10 min to 30 min.

[0029] Preferably, the number of rolling operations is 4-6 times.

[0030] Preferably, the drying temperature is 55°C-65°C and the drying time is 10 min-30 min. S5. Performing a hot pressing process on the nano-metal particle modified fabric with phenolic resin to obtain a nano-metal particle modified fabric pad.

[0031] Specifically, the modified fabric loaded with nano-metal particles impregnated with phenolic resin is cured and formed by hot pressing, wherein the pressure required to be applied during the curing process is 0.5 MPa-2 MPa, the hot pressing temperature is 160°C-200°C, and the hot pressing time is 1 h-3 h.

[0032] Preferably, the hot pressing stage can be divided into two stages: In the first stage, the temperature is raised to 80-120 °C at a heating rate of 1-3 °C / min and maintained for 50-80 min. In the second stage, the temperature is raised to 160 ℃-200 ℃ at a heating rate of 1 ℃ / min-3 ℃ / min and maintained for 50 min-80 min.

[0033] The present invention also provides a self-lubricating bearing liner modified and enhanced by Ag nanoparticles, comprising: a fiber fabric and an impregnating resin loaded on the fiber fabric, wherein the surface of the fiber fabric has a dense metallic silver layer.

[0034] In one embodiment, the fabric comprises a blended fabric of reinforcing phase fibers and lubricating phase fibers, and the surface density of the fabric is 200-500 g / m 2 , fiber fineness is 300 D-1200 D, thickness is 0.25 -0.50 mm.

[0035] In a specific embodiment, the impregnating resin is a phenolic resin, and the mass ratio of the impregnating resin is 15-35%.

[0036] Example 2 The method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles in this embodiment includes the following steps: (1) mixing anhydrous ethanol and ethyl acetate in a mass ratio of 1:1 to obtain a diluent, and mixing the diluent and phenolic resin in a mass ratio of 1:7 to obtain an impregnation solution; (2) The three-way orthogonal blended aramid / PTFE fabric was cleaned with acetone and ethanol in sequence, ultrasonicated for 2 h, and dried; (3) The dried three-dimensional orthogonal blended aramid / PTFE fabric obtained in step (2) was placed in 50 ml of anhydrous ethanol, 50 ml of deionized water, and 5 g of tannic acid buffer solution and soaked for 12 h; (4) The sensitized three-dimensional orthogonal mixed aramid / PTFE fabric obtained in step (3) was placed in a reactor for hydrothermal reaction. 2 mmol of AgNO3 solution and 2 mmol of terephthalic acid were dissolved in 40 mL of N,N-dimethylacetamide, stirred for 30 min in the dark, added to a 100 mL reactor, heated at 140°C for 10 h, washed twice, placed in an oven and dried at 60°C for 8 h; (5) The Ag-MOF modified three-dimensional orthogonal mixed aramid / PTFE fabric obtained in step (4) was placed in a tube furnace for high-temperature reduction reaction and sintered in the tube furnace at 280°C for 2 h.

[0037] (6) The three-dimensional orthogonal hybrid aramid / PTFE fabric modified with nano-Ag particles obtained in step (5) is immersed in a phenolic resin dilution solution, and the immersion is repeated, and the roller is pressed and dried until the mass fraction reaches 30%; (7) A layer of non-stick paper was placed on the upper and lower surfaces of the Ag@three-dimensional orthogonal blended aramid / PTFE with phenolic resin obtained in step (6), and then hot-pressed on a hot press at a temperature of 180°C, a pressure of 0.5 MPa, and a time of 3 h to obtain an Ag nanoparticle-modified self-lubricating fabric pad.

[0038] Example 3 The method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles in this embodiment includes the following steps: (1) mixing anhydrous ethanol and ethyl acetate in a mass ratio of 1:1 to obtain a diluent, and mixing the diluent and phenolic resin in a mass ratio of 1:7 to obtain an impregnation solution; (2) The 2.5D blended aramid / PTFE fabric was washed with acetone and ethanol, ultrasonicated for 2 h, and dried; (3) The dried 2.5D mixed aramid / PTFE fabric obtained in step (2) was placed in 50 ml of anhydrous ethanol, 50 ml of deionized water, and 5 g of tannic acid buffer solution and soaked for 12 h; (4) The sensitized 2.5D mixed aramid / PTFE fabric obtained in step (3) was placed in a reactor for hydrothermal reaction. 2 mmol of AgNO3 solution and 2 mmol of terephthalic acid were dissolved in 40 mL of N,N-dimethylacetamide, stirred for 30 min in the dark, added to a 100 mL reactor, heated at 140°C for 10 h, washed twice, placed in an oven and dried at 60°C for 8 h; (5) The Ag-MOF modified 2.5D mixed aramid / PTFE fabric obtained in step (4) was placed in a tube furnace for high-temperature reduction reaction and sintered in the tube furnace at 280°C for 2 h.

[0039] (6) The 2.5D mixed aramid / PTFE fabric modified with nano-Ag particles obtained in step (5) was immersed in a phenolic resin dilution solution, and the immersion was repeated and roller-pressed and dried until the mass fraction reached 30%; (7) A layer of non-stick paper was placed on the upper and lower surfaces of the Ag@2.5D mixed aramid / PTFE with phenolic resin obtained in step (6), and then hot-pressed on a hot press at a temperature of 180°C, a pressure of 0.5 MPa, and a time of 3 h to obtain an Ag nanoparticle-modified self-lubricating fabric pad.

[0040] Example 4 The method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles in this embodiment includes the following steps: (1) mixing anhydrous ethanol and ethyl acetate in a mass ratio of 1:1 to obtain a diluent, and mixing the diluent and phenolic resin in a mass ratio of 1:7 to obtain an impregnation solution; (2) The three-dimensional orthogonal mixed basalt / PTFE fabric was washed with acetone and ethanol in sequence, ultrasonicated for 2 h and dried; (3) The dried three-dimensional orthogonal mixed basalt / PTFE fabric obtained in step (2) was placed in 50 ml of anhydrous ethanol, 50 ml of deionized water, and 5 g of tannic acid buffer solution and soaked for 12 h; (4) The sensitized three-dimensional orthogonal mixed basalt / PTFE fabric obtained in step (3) was placed in a reactor for hydrothermal reaction. 4 mmol of AgNO3 solution and 2 mmol of terephthalic acid were dissolved in 40 mL of N,N-dimethylacetamide, stirred for 30 min in the dark, added to a 100 mL reactor, heated at 140°C for 10 h, washed twice, placed in an oven and dried at 60°C for 8 h; (5) The Ag-MOF modified three-dimensional orthogonal mixed basalt / PTFE fabric obtained in step (4) was placed in a tube furnace for high-temperature reduction reaction and sintered in the tube furnace at 280°C for 2 h.

[0041] (6) The three-dimensional orthogonal mixed basalt / PTFE fabric modified with nano-Ag particles obtained in step (5) is immersed in a phenolic resin dilution solution, and the immersion is repeated, and the roller is pressed and dried until the mass fraction reaches 30%; (7) A layer of non-stick paper was placed on the upper and lower surfaces of the Ag@three-dimensional orthogonal mixed basalt / PTFE with phenolic resin obtained in step (6), and then hot-pressed on a hot press at a temperature of 180°C, a pressure of 0.5 MPa, and a time of 3 h to obtain an Ag nanoparticle-modified self-lubricating fabric pad.

[0042] Example 5 The method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles in this embodiment includes the following steps: (1) mixing anhydrous ethanol and ethyl acetate in a mass ratio of 1:1 to obtain a diluent, and mixing the diluent and phenolic resin in a mass ratio of 1:7 to obtain an impregnation solution; (2) The three-way orthogonal blended aramid / PTFE fabric was cleaned with acetone and ethanol in sequence, ultrasonicated for 2 h, and dried; (3) The dried three-dimensional orthogonal blended aramid / PTFE fabric obtained in step (2) was placed in 50 ml of anhydrous ethanol, 50 ml of deionized water, and 5 g of tannic acid buffer solution and soaked for 12 h; (4) The sensitized three-dimensional orthogonal mixed aramid / PTFE fabric obtained in step (3) was placed in a reactor for hydrothermal reaction. 6 mmol of AgNO3 solution and 2 mmol of terephthalic acid were dissolved in 40 mL of N,N-dimethylacetamide, stirred for 30 min in the dark, added to a 100 mL reactor, heated at 140°C for 10 h, washed twice, placed in an oven and dried at 60°C for 8 h; (5) The Ag-MOF modified three-dimensional orthogonal mixed aramid / PTFE fabric obtained in step (4) was placed in a tube furnace for high-temperature reduction reaction and sintered in the tube furnace at 280°C for 2 h.

[0043] (6) The three-dimensional orthogonal hybrid aramid / PTFE fabric modified with nano-Ag particles obtained in step (5) is immersed in a phenolic resin dilution solution, and the immersion is repeated, and the roller is pressed and dried until the mass fraction reaches 30%; (7) A layer of non-stick paper was placed on the upper and lower surfaces of the Ag@three-dimensional orthogonal blended aramid / PTFE with phenolic resin obtained in step (6), and then hot-pressed on a hot press at a temperature of 180°C, a pressure of 0.5 MPa, and a time of 3 h to obtain an Ag nanoparticle-modified self-lubricating fabric pad.

[0044] Comparative Example 1 (1) mixing anhydrous ethanol and ethyl acetate in a mass ratio of 1:1 to obtain a diluent, and mixing the diluent and phenolic resin in a mass ratio of 1:7 to obtain a phenolic resin impregnation solution; (2) The three-dimensional aramid / PTFE fabric, which had been washed with acetone / ethanol in sequence, was immersed in the impregnation solution. Ultrasonic vibration was used during the impregnation process for 30 min. After impregnation and roller pressing, the fabric was dried in an oven at 60°C. The impregnation, roller pressing, and drying process were repeated until the mass fraction reached 30%. (3) After step (2), a layer of non-stick paper is placed on the upper and lower surfaces of the fiber fabric, and then hot-pressed on a hot press at a temperature of 180° C., a pressure of 0.5 MPa, and a time of 3 h to obtain a self-lubricating fabric liner; Comparative Example 2 A self-lubricating fabric liner was prepared according to the method of Comparative Example 1, except that the mixed fiber fabric structure was changed from a three-way orthogonal fabric to a twill.

[0045] Comparative Example 3 A self-lubricating fabric liner was prepared according to the method of Comparative Example 1, except that the three-dimensional aramid / PTFE fabric was modified with Ag nanoparticles.

[0046] Comparative Example 4 A self-lubricating fabric liner was prepared according to the method of Comparative Example 1, except that the mixed fiber fabric structure was changed from a three-dimensional orthogonal fabric to a 2.5D fabric structure.

[0047] For specific experimental results, please refer to Table 1, which shows the average friction coefficient and average wear rate of the friction tests of each embodiment and each comparative example. It can be clearly seen that the friction coefficient and wear rate of Examples 2-5 of the present application are generally better than those of Comparative Examples 1-4, and the effect of Example 4 is the best. This is because when the silver ion concentration is too low (for example, 1:1), the nanoparticles on the fiber surface are uneven and there is insufficient coverage. When the silver ion concentration is too high (for example, 3:1), the silver ions will form agglomerates on the fiber surface, thereby affecting performance. At a moderate silver ion concentration (for example, 2:1), the silver ions can be evenly covered on the fiber surface and will not agglomerate, thus reflecting the optimal friction coefficient and average wear rate.

[0048] Table 1 Specifically, from Figure 2a It can be seen that the surface of the unmodified fiber is smooth and its high-temperature lubrication performance is low; Figure 2b In the process, there is a continuous and dense Ag nanoparticle layer on the fiber surface, which realizes continuous thermal conduction and constructs a three-dimensional continuous thermal conductive composite material system, thereby improving its thermal conductivity and high-temperature lubrication performance. Figure 3a In the friction test, severe fiber breakage and resin delamination can be observed for the unmodified fibers, accompanied by a thick and weakly adhered transfer film. Figure 3b The fibers modified with Ag nanoparticles exhibited excellent wear resistance, with only slight wear marks on the surface.

[0049] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0050] Although the present application is described herein in conjunction with various embodiments, in the process of implementing the claimed application, those skilled in the art can understand and implement other changes to the disclosed embodiments by reviewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple situations. A single processor or other unit can implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0051] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A method for preparing a self-lubricating bearing liner modified and enhanced with Ag nanoparticles, characterized in that: include: S1. Modifying the surface of the fabric to form active reaction sites on the fabric surface to obtain a sensitized fabric; S2, dissolving metallic silver ions and organic ligands in an organic solvent, stirring the solvent in the absence of light to uniformly mix the metallic silver ions and the organic ligands to obtain a metal mixture, transferring the metal mixture and the sensitized fabric into a polytetrafluoroethylene-lined reactor and heating for several hours to modify the fabric; S3. Putting the modified fabric into a tube furnace and subjecting the modified fabric to high-temperature reduction treatment in a nitrogen atmosphere to form a dense metallic silver layer on the surface of the modified fabric to obtain nano-metal particle modified fabric.

2. The method for preparing a self-lubricating bearing liner modified and enhanced by Ag nanoparticles according to claim 1, characterized in that: The fabric comprises a mixed fabric of reinforcing phase fibers and lubricating phase fibers.

3. The method for preparing a self-lubricating bearing liner modified and enhanced by Ag nanoparticles according to claim 2, characterized in that: The surface density of the fabric is 200-500 g / m 2 , fiber fineness is 300 D-1200 D, thickness is 0.25 -0.50mm.

4. The method for preparing a self-lubricating bearing liner modified and enhanced by Ag nanoparticles according to claim 1, characterized in that: The step S1 specifically includes: The fabric was ultrasonically cleaned using acetone and ethanol; The ultrasonically cleaned fabric is immersed in a sensitizer for modification to construct active reaction sites to obtain a sensitized fabric.

5. The method for preparing a self-lubricating bearing liner modified and enhanced by Ag nanoparticles according to claim 4, characterized in that: The sensitizer is a tannic acid solution, which includes a tannic acid body and a mixed solvent. The mixed solvent is an ethanol aqueous solution, and the mass ratio of the tannic acid body to the ethanol aqueous solution is (0.05-0.2):

1.

6. The method for preparing a self-lubricating bearing liner modified and enhanced by Ag nanoparticles according to claim 1, characterized in that: The organic ligand is terephthalic acid, and the molar ratio of the metal silver ion to the organic ligand is (1-3):

1.

7. The method for preparing a self-lubricating bearing liner modified and enhanced by Ag nanoparticles according to claim 1, characterized in that: The S3 step further includes: S4, immersing the nano-metal particle modified fabric in a phenolic resin dilution solution, repeatedly immersing and roller-drying until the mass fraction of the phenolic resin is at least 15% to obtain a nano-metal particle modified fabric with phenolic resin; S5. Performing a hot pressing process on the nano-metal particle modified fabric with phenolic resin to obtain a nano-metal particle modified fabric pad.

8. A self-lubricating bearing liner modified and enhanced with Ag nanoparticles, characterized in that: include: The invention relates to a fiber fabric and an impregnating resin supported on the fiber fabric, wherein the surface of the fiber fabric is provided with a dense metallic silver layer.

9. The Ag nanoparticle modified and enhanced self-lubricating bearing liner according to claim 8, characterized in that: The fabric comprises a blended fabric of reinforcing phase fibers and lubricating phase fibers, and the surface density of the fabric is 200-500 g / m 2 , fiber fineness is 300 D-1200 D, thickness is 0.25 -0.50 mm.

10. The Ag nanoparticle modified and enhanced self-lubricating bearing liner according to claim 8, characterized in that: The impregnating resin is phenolic resin, and the mass ratio of the impregnating resin is 15-35%.

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