Self-lubricating plain bearing and method for producing same

Abstract

This invention proposes a method for preparing a self-lubricating sliding bearing. The method includes the following steps: adding wear-resistant fillers and reinforcing fillers to a thermosetting resin, stirring, and then vacuuming at room temperature before pouring the mixture into the gap between the inner and outer rings of the sliding bearing; placing the sliding bearing in an SPS (spark plasma) sintering furnace mold, setting the heating rate, and performing initial curing of the resin at the initial curing temperature, followed by post-curing at the post-curing temperature, to obtain a fully cured self-lubricating sliding bearing. This invention fills a technological gap and solves the problems of defects such as voids, insufficient material, and cracking that easily occur in bearing liner molding. Furthermore, the raw materials used in this method are readily available, the operation is simple and easy to control, there is no pollution, the reaction conditions are mild, and industrial production is possible, giving it significant market potential and economic value.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of self-lubricating polymer liner forming and curing of sliding bearing, in particular to a preparation method of self-lubricating sliding bearing. BACKGROUND

[0002] The self-lubricating sliding bearing includes a radial sliding bearing and an axial sliding bearing, which is composed of a metal inner and outer ring and a self-lubricating polymer liner. The self-lubricating liner can play a role of bearing and lubrication, which can convert the friction between the inner ring metal and the outer ring metal of the sliding bearing into the friction between the inner ring metal and the polymer liner, so as to reduce the friction coefficient, reduce the wear and reduce the heat generation. The preparation of the self-lubricating polymer liner generally uses a thermosetting resin as a carrier, and adds a proper amount of lubricating and reinforcing filler to improve the lubricating and bearing performance.

[0003] The thermosetting resin refers to a resin which gradually solidifies and forms after chemical cross-linking reaction under heating, and cannot be dissolved in a solvent again after heating. The thermosetting resin has a three-dimensional cross-linked network structure, is not easy to deform under pressure, and the mechanical properties are greatly affected by the type of matrix. The thermosetting resin includes phenolic, epoxy, amino, unsaturated polyester and siloxane resin, etc. Under heating, pressure or the action of curing agent and ultraviolet light, the thermosetting resin is chemically reacted and cross-linked to become a kind of synthetic resin which is insoluble and infusible. The resin is generally a solid or viscous liquid with low molecular weight before curing; it can be softened or flowed during the forming process, has plasticity, and can be formed into a certain shape, and at the same time, it is chemically cross-linked and cured; sometimes some by-products such as water are generated. The reaction is irreversible, and once cured, it cannot be softened or flowed again under pressure and heating; if the temperature is too high, it will be decomposed or carbonized.

[0004] Due to the small gap between the inner and outer rings of the sliding bearing, which is only about 0.5 mm, and the high viscosity and poor flowability of the thermosetting resin after adding fillers, the traditional resin pouring forming technology is prone to defects such as holes, underfilling and cracking after curing, which seriously affects the performance of the sliding bearing. When the content of the filler increases, the resin has almost no flowability, which greatly limits the optimization and innovation of the liner formula. The SPS plasma sintering furnace as a new type of rapid sintering technology can rapidly heat the sample and provide a certain pressure, so that the pressure and temperature can be provided in the curing process of the sliding bearing liner by using this technology, the density of the liner is improved during the curing process, and the defect problem is solved. SUMMARY

[0005] In order to overcome the product defects caused by the traditional self-lubricating liner curing technology, the present application provides a preparation method of self-lubricating sliding bearing to solve the problem of poor performance of the self-lubricating polymer liner of the sliding bearing after forming and curing, which comprises the following steps:

[0006] (1) pouring a resin composition containing a thermosetting resin, a wear-resistant filler and a reinforcing filler into the bearing inner and outer ring gap of a sliding bearing;

[0007] (2) placing the sliding bearing poured with the resin composition into an SPS discharge plasma sintering furnace mold for preliminary curing, and obtaining a self-lubricating sliding bearing with complete resin curing through post-curing.

[0008] In the preparation method, the thermosetting resin is selected from at least one of epoxy resin, phenolic resin, unsaturated polyester resin, melamine-formaldehyde resin and urea-formaldehyde resin.

[0009] The wear-resistant filler is selected from at least one of microcapsules, graphene, polytetrafluoroethylene powder / fiber, graphite, molybdenum disulfide, hexagonal boron nitride and zirconium oxide, and the reinforcing filler is selected from at least one of metal powder, carbon fiber, glass fiber, whisker, silicon dioxide and carbon nanotube.

[0010] In step (1), the mass percentage of the wear-resistant filler is 10-80%, preferably 30-60%.

[0011] In step (1), the mass percentage of the reinforcing filler is 2-30%, preferably 5-20%.

[0012] In step (1), the resin composition is prepared by adding the wear-resistant filler and the reinforcing filler to the thermosetting resin, stirring and vacuumizing at room temperature.

[0013] Preferably, the stirring rate is 1000-5000 r / min, preferably 2000-3000 r / min.

[0014] Preferably, the vacuum degree is 10-500 KPa, preferably 50-200 KPa.

[0015] The stirring and vacuumizing further include ultrasonic dispersion, and the ultrasonic dispersion is performed for 10 min.

[0016] In step (2), the inner diameter of the SPS discharge plasma sintering furnace mold is 50-80 mm, preferably 55-60 mm, and the outer diameter of the SPS discharge plasma sintering furnace mold is 90-130 mm, preferably 90-100 mm.

[0017] In step (2), the initial curing temperature of the SPS discharge plasma sintering furnace heating rate is 60-150℃, preferably 80-120℃.

[0018] In step (2), the time for preliminary curing is 2-4 hours, and the pressure for preliminary curing is 0.2-40 MPa, preferably 2-10 MPa.

[0019] In step (2), the heating rate of the SPS discharge plasma sintering furnace is 2-12 K / min, preferably 5-10 K / min.

[0020] In step (2), the temperature of the post-curing is 140-200℃, preferably 160-180℃; the time is 10-50h, preferably 20-30h.

[0021] In step (1), the resin composition further comprises other auxiliary agents, which are any one of curing agents, catalysts;

[0022] Preferably, the curing agent and the catalyst are selected from any one of peroxide, organic acid, diamine polyamine, and ammonium chloride, wherein the mass ratio of the curing agent is 0.1-5%, preferably 1-2%, and the mass ratio of the catalyst is 0.1-2%, preferably 0.4-0.8%.

[0023] The above raw materials in the present application can be self-made or commercially available, and the present application does not make special limitations thereon.

[0024] In another aspect of the present application, a self-lubricating sliding bearing prepared by the above method is provided.

[0025] The method of the present application fills the technical gap and solves the problems of defects such as holes, insufficient material, and cracking in the forming of bearing pads. At the same time, the raw materials of the method are easy to obtain, the operation is simple and easy to control, there is no pollution, the reaction conditions are mild, industrial production can be realized, and the method has great market prospect and economic value.

[0026] The accompanying drawings

[0027] Figure 1 Test results for Example 1;

[0028] Figure 2 Test results for Example 2;

[0029] Figure 3 Test results for Example 3;

[0030] Figure 4 Test results for Example 4;

[0031] Figure 5 Test results for Example 5;

[0032] Figure 6 Test results for Comparative Example 1. DETAILED DESCRIPTION

[0033] The following will specifically describe the present application in combination with specific examples. It is necessary to point out that the following examples are only used for further illustration of the present application and cannot be understood as a limitation to the protection scope of the present application. Some non-essential improvements and adjustments to the present application made by those skilled in the art according to the content of the present application still fall within the protection scope of the present application.

[0034] The raw materials used in the present application are commercially available.

[0035] Example 1

[0036] In a 250ml beaker, 100g of unsaturated polyester resin (grade 901), 10g of carbon fiber (100 mesh), 10g of glass fiber (100 mesh), 5g of silicon dioxide (1 μm), 50g of polytetrafluoroethylene powder (200 μm) (the polytetrafluoroethylene powder herein can be replaced by polytetrafluoroethylene fiber), were added, and after being fully stirred, ultrasonic dispersion was performed for 10 min. 2.3g of peroxyketone was added, and after being uniformly stirred at a stirring rate of 1000r / min, the material was placed in a vacuum environment to remove dissolved air and moisture in the material, and the vacuum degree was 10KPa. The material was poured into the gap between the inner and outer rings of a sliding bearing (bearing inner and outer ring gap 0.2-2mm). The filled bearing was placed in an SPS discharge plasma sintering furnace, and the resin liner was preliminarily cured. The heating rate was set to 12K / min, the preliminary curing temperature was 60℃, the preliminary curing time was 4h, and the pressure was set to 0.2MPa. After the preliminary curing was completed, the bearing was placed in a higher temperature environment for post-curing. The post-curing temperature was 160℃, and the post-curing time was 50h, thereby obtaining a self-lubricating sliding bearing.

[0037] The inner diameter of the SPS discharge plasma sintering furnace mold was 50mm, and the outer diameter of the SPS discharge plasma sintering furnace mold was 90mm.

[0038] The self-lubricating sliding bearing prepared was subjected to performance testing. The test load was 100KN, the frequency was 1Hz, and the swing angle was ±25°. The test results are shown in Figure 1 The bearing liner was worn by 0.2mm under this working condition for 14h.

[0039] Example 2

[0040] In a 250ml beaker, 100g epoxy resin (grade 191), 11g carbon fiber (100 mesh), 11g glass fiber (100 mesh), 5g graphite (3pm) were added, stirred thoroughly and then ultrasonic dispersed for 10min, 5g boron trifluoride ethylamine was added, stirred uniformly, stirring rate was 5000r / min; put into a vacuum environment to remove the dissolved air and moisture in the material, vacuum degree was 500KPa, poured into the bearing inner and outer ring gap of the sliding bearing. The filled bearing was placed in the SPS discharge plasma sintering furnace, the resin liner was preliminarily cured, the heating rate was set to 10K / min, the preliminary curing temperature was 80℃, the preliminary curing time was 3h, and the pressure was set to 40MPa. After the preliminary curing was completed, the bearing was placed in a higher temperature environment for post-curing, the post-curing temperature was 140℃, the post-curing time was 10h, and the self-lubricating sliding bearing was obtained.

[0041] The inner diameter of the SPS discharge plasma sintering furnace mold was 80mm, and the outer diameter of the SPS discharge plasma sintering furnace mold was 130mm.

[0042] The prepared self-lubricating sliding bearing was tested for performance, the test load was 100KN, the frequency was 1Hz, and the swing angle was ±25°, and the test results were as shown in Figure 2 The bearing liner was worn by 0.2mm under this working condition for 36h.

[0043] Example 3

[0044] In a 250ml beaker, 100g epoxy resin (grade 191), 11g carbon fiber (100 mesh), 11g glass fiber (100 mesh), 5g graphite (3pm) were added, stirred thoroughly and then ultrasonic dispersed for 10min, 5g boron trifluoride ethylamine was added, stirred uniformly, stirring rate was 5000r / min; put into a vacuum environment to remove the dissolved air and moisture in the material, vacuum degree was 500KPa, poured into the bearing inner and outer ring gap of the sliding bearing. The filled bearing was placed in the SPS discharge plasma sintering furnace, the resin liner was preliminarily cured, the heating rate was set to 10K / min, the preliminary curing temperature was 80℃, the preliminary curing time was 3h, and the pressure was set to 40MPa. After the preliminary curing was completed, the bearing was placed in a higher temperature environment for post-curing, the post-curing temperature was 140℃, the post-curing time was 10h, and the self-lubricating sliding bearing was obtained.

[0045] The inner diameter of the SPS discharge plasma sintering furnace mold was 80mm, and the outer diameter of the SPS discharge plasma sintering furnace mold was 130mm.

[0046] The prepared self-lubricating sliding bearing was tested for performance, the test load was 100KN, the frequency was 1Hz, and the swing angle was ±25°, and the test results were as shown inFigure 3 The bearing liner is shown to wear 0.2 mm under this working condition for 10 h.

[0047] Example 4

[0048] In a 250 ml beaker, 100 g of urea-formaldehyde resin (grade T-2), 13 g of carbon fiber (100 mesh), 10 g of glass fiber (100 mesh), 5 g of zirconium oxide (4 μm) were added, and after being fully stirred, ultrasonic dispersion was performed for 10 min, 1 g of ammonium chloride was added, and uniform stirring was performed at a stirring rate of 3000 r / min; the dissolved air and moisture in the material were removed in a vacuum environment, the vacuum degree was 200 KPa, and the material was poured into the gap between the inner and outer rings of the sliding bearing. The filled bearing was placed in an SPS discharge plasma sintering furnace, preliminary curing of the resin liner was performed, the heating rate was set to 5 K / min, the preliminary curing temperature was 120 °C, the preliminary curing time was 2 h, and the pressure was set to 2 MPa. After the preliminary curing was completed, the bearing was placed in a higher temperature environment for post-curing, the post-curing temperature was 180 °C, the post-curing time was 30 h, and a self-lubricating sliding bearing was obtained.

[0049] The inner diameter of the SPS discharge plasma sintering furnace mold was 60 mm, and the outer diameter of the SPS discharge plasma sintering furnace mold was 100 mm.

[0050] The self-lubricating sliding bearing prepared was subjected to performance testing, the test load was 100 KN, the frequency was 1 Hz, the swing angle was ± 25 °, and the test results are shown in Table 1. Figure 4 The bearing liner is shown to wear 0.2 mm under this working condition for 5 h.

[0051] Example 5

[0052] In a 250 ml beaker, 100 g of urea-formaldehyde resin (grade T-2), 13 g of carbon fiber (100 mesh), 10 g of glass fiber (100 mesh), 5 g of zirconium oxide (4 μm) were added, and after being fully stirred, ultrasonic dispersion was performed for 10 min, 1 g of ammonium chloride was added, and uniform stirring was performed at a stirring rate of 3000 r / min; the dissolved air and moisture in the material were removed in a vacuum environment, the vacuum degree was 200 KPa, and the material was poured into the gap between the inner and outer rings of the sliding bearing. The filled bearing was placed in an SPS discharge plasma sintering furnace, preliminary curing of the resin liner was performed, the heating rate was set to 5 K / min, the preliminary curing temperature was 120 °C, the preliminary curing time was 2 h, and the pressure was set to 2 MPa. After the preliminary curing was completed, the bearing was placed in a higher temperature environment for post-curing, the post-curing temperature was 180 °C, the post-curing time was 30 h, and a self-lubricating sliding bearing was obtained.

[0053] The inner diameter of the SPS discharge plasma sintering furnace mold is 60mm, and the outer diameter of the SPS discharge plasma sintering furnace mold is 100mm.

[0054] The prepared self-lubricating sliding bearing was subjected to performance testing. The test load was 100 kN, the frequency was 1 Hz, and the swing angle was ±25°. The test results are as follows: Figure 5 As shown, the bearing liner wears 0.2 mm in 6 hours under this operating condition.

[0055] Comparative Example 1

[0056] Add 100g of unsaturated polyester resin (grade 901), 10g of carbon fiber (100 mesh), and 2g of butanone peroxide to a 250ml beaker. Stir well and pour the mixture into the gap between the inner and outer rings of the sliding bearing. Place the filled bearing in an oven for initial curing at 70℃ for 4 hours. After initial curing, place the bearing in a higher temperature environment for post-curing at 150℃ for 20 hours to obtain a self-lubricating sliding bearing. Perform performance tests on the prepared self-lubricating sliding bearing. The test load is 100KN, the frequency is 1Hz, and the swing angle is ±25°. The test results are as follows: Figure 6 As shown, the bearing liner wears 0.2 mm in 0.1 hours under this operating condition.

[0057] Any numerical value mentioned in this invention, if there is only a two-unit interval between any minimum and any maximum value, includes all values ​​that increase by one unit each time from the minimum to the maximum value. For example, if the amount of a component, or the value of a process variable such as temperature, pressure, or time, is stated as 50-90, in this specification it means specifically listing values ​​such as 51-89, 52-88… and 69-71 and 70-71, etc. For non-integer values, it may be appropriately considered that a unit is 0.1, 0.01, 0.001, or 0.0001. These are merely some specifically specified examples. In this application, in a similar manner, all possible combinations of numerical values ​​between the listed minimum and maximum values ​​are considered to have been disclosed.

[0058] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

Claims

1. A method for preparing a self-lubricating sliding bearing, comprising the following steps: (1) pouring a resin composition comprising a thermosetting resin, a wear-resistant filler and a reinforcing filler into the gap between the inner and outer rings of the sliding bearing; (2) placing the sliding bearing with the poured resin composition into an SPS discharge plasma sintering furnace mold for preliminary curing, and obtaining a self-lubricating sliding bearing with complete resin curing through post-curing; in step (2), the temperature of the preliminary curing of the SPS discharge plasma sintering furnace is 60-150℃, and the time of the preliminary curing is 2-4 hours; in step (2), the temperature of the post-curing is 140-200℃, and the time of the post-curing is 10-50 hours; the thermosetting resin is at least one selected from the group consisting of epoxy resin, phenolic resin, unsaturated polyester resin, melamine-formaldehyde resin and urea-formaldehyde resin; the wear-resistant filler is at least one selected from the group consisting of microcapsule, graphene, polytetrafluoroethylene powder, polytetrafluoroethylene fiber, graphite, molybdenum disulfide, hexagonal boron nitride and zirconium oxide; and / or the reinforcing filler is at least one selected from the group consisting of metal powder, carbon fiber, glass fiber, whisker, silicon dioxide and carbon nanotube; in step (1), the mass percentage of the wear-resistant filler is 10-80wt%; in step (1), the mass percentage of the reinforcing filler is 2-30%; in step (1), the mass percentage of the wear-resistant filler is 30-60wt%; in step (1), the mass percentage of the reinforcing filler is 5-20%; in step (1), the resin composition is prepared by adding the wear-resistant filler and the reinforcing filler to the thermosetting resin, stirring and vacuumizing at room temperature; in step (1), the stirring rate is 1000-5000r / min; and / or the vacuum degree is 10-500KPa; in step (1), the stirring rate is 2000-3000r / min; and / or the vacuum degree is 50-200KPa; the stirring and vacuumizing further comprise ultrasonic dispersion for 10min; in step (2), the inner diameter of the SPS discharge plasma sintering furnace mold is 50-80mm, and the outer diameter of the SPS discharge plasma sintering furnace mold is 90-130mm; and / or in step (2), the pressure of the preliminary curing is 0.2-40MPa; in step (2), the inner diameter of the SPS discharge plasma sintering furnace mold is 55-60mm, and the outer diameter of the SPS discharge plasma sintering furnace mold is 90-100mm; and / or in step (2), the temperature of the preliminary curing of the SPS discharge plasma sintering furnace is 80-120℃; and / or in step (2), the pressure of the preliminary curing is 2-10MPa; in step (2), the heating rate of the SPS discharge plasma sintering furnace is 2-12K / min; in step (2), the temperature of the post-curing is 160-180℃, and the time of the post-curing is 20-30h; and in step (1), the resin composition further comprises other auxiliaries, which are any one of a curing agent and a catalyst. ​ ​ ​ ​ ​ 2. The method of claim 1, wherein: ​ ​ 3. The method of claim 1, wherein: ​ ​ 4. The method of claim 3, wherein: ​ ​ 5. The method of any one of claims 1-4, wherein: ​ 6. The method of claim 5, wherein: ​ ​ 7. The method of claim 6, wherein: ​ ​ 8. The method of claim 5, wherein: ​ 9. The method of any one of claims 1-4, wherein: ​ ​ 10. The method of any one of claims 1-4, wherein: ​ ​ ​ 11. The method of claim 10, wherein: ​ 12. The method of claim 10, wherein: ​ 13. The method of making according to any one of claims 1-4, wherein: ​ 14. The method of claim 13, wherein: The curing agent and the catalyst are selected from any one of peroxide, organic acid, diamine polyamine and ammonium chloride, wherein the mass percentage of the curing agent is 0.1-5%, and the mass percentage of the catalyst is 0.1-2%.

15. The method of claim 13, wherein: The mass percentage of the curing agent is 1-2%, and the mass percentage of the catalyst is 0.4-0.8%.

16. A self-lubricating plain bearing obtainable by the production method according to any one of claims 1 to 15.

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