A kind of antifriction composite material and its super-slippery system and application

Abstract

The application provides a kind of antifriction composite material and its super slippery system and application, the antifriction composite material includes polymer base plate and polyimide film pasted on polymer base plate, the polymer base plate is polyether ether ketone or polytetrafluoroethylene, the super slippery system is obtained by adding lubricant after antifriction composite material and bearing steel as friction pair.The application realizes that the friction coefficient of system sliding is to 0.001 order of magnitude, super low friction phenomenon occurs, and is applied in dynamic seal in mechanical field.

Description

Technical Field

[0001] This invention relates to the field of aerospace lubrication materials technology, specifically a friction-reducing composite material and its super-lubricating system and applications. Background Technology

[0002] Dynamic seals refer to the seals between relatively moving parts in a machine (or equipment), typically achieved through the interaction between the seal and a rotatable, movable component. Dynamic sealing technology is generally divided into two types: direct contact and indirect contact. Direct contact dynamic seals achieve high sealing performance by using friction sealing at the contact point between the seal surface and the component. Sealing technology is prevalent in the industrial field, influencing the system performance of engineering machinery. For example, aerospace seals are used in the aviation industry, primarily to prevent the leakage or entry of gases, liquids, and solid particles from or into the aircraft. Aerospace seals typically require characteristics such as high temperature, high pressure, corrosion resistance, low friction, and wear resistance to ensure their reliability and safety in extreme environments. Aerospace seals are widely used in flight components and are a crucial component ensuring the normal operation of these components. The design and quality of dynamic seals directly affect the performance of aviation equipment and flight safety; failure of dynamic seals can reduce system efficiency, causing reduced output or stroke, or even prevent the system from operating as intended, leading to serious accidents. In other areas, such as the design of seals for new energy vehicles, the requirements also need to be adapted to the specific needs of new energy vehicles. For example, seals in the motors of new energy vehicles need to withstand a wider temperature range while meeting requirements for friction reduction, insulation, noise reduction, and vibration damping. In terms of reliability, damage to seals will affect the overall vehicle's operation; in terms of safety, some seals have very specific installation locations, and a failure in these locations will compromise the safety of the entire vehicle. Regarding comfort, bearing seals are closely related to the smooth operation of the vehicle and the generation of noise.

[0003] Therefore, the design and development of novel lubrication systems for seals has always been a hot topic in the mechanical field. The performance of seals directly affects the safety and stability of machine operation, making them extremely important. With the rapid development of industry, improving the reliability of dynamic seals and reducing energy consumption have become one of the focal points in the mechanical field. Friction control in sealing systems is crucial. Once friction becomes controllable, or even super-lubrication occurs, it can better ensure the high precision, high sensitivity, and long lifespan of mechanical components. With the development of advanced manufacturing technology, precision control of mechanical equipment has become an important trend in modern industry. Precision lubrication usually requires maximizing friction control and minimizing friction. Although the unique properties of super-lubrication behavior and the important role of seals have attracted attention and led to corresponding research and applications, research on super-lubrication of novel seals is still in its infancy both domestically and internationally, and there is no work specifically on the design and application of super-lubrication systems for dynamic seals. The design and development of novel lubrication systems is one of the effective ways to solve this problem. Summary of the Invention

[0004] To address the shortcomings of the existing technologies, this invention provides a friction-reducing composite material, its super-lubricating system, and its applications, achieving a friction coefficient of up to 0.001 during system sliding, resulting in ultra-low friction, and applying it to dynamic seals in the field of mechanical manufacturing.

[0005] The technical solution provided by this invention is a friction-reducing composite material, comprising a polymer base plate used as a sealing material and a polyimide film adhered to the polymer base plate. The polymer base plate is a polymer material used as a sealing material: polyether ether ketone (PEEK) or polytetrafluoroethylene (PTFE). The surface of the material is modified based on the existing material, with the aim of improving the friction performance of the material surface while retaining the excellent mechanical properties of the original sealing material.

[0006] Furthermore, the polyimide film (PI) is a PMDA-ODA type polyimide film.

[0007] Furthermore, the polyimide film is adhered to the polymer substrate using SH-916 adhesive or acrylic AB adhesive.

[0008] Another technical solution provided by the present invention is a super-lubricating system, which uses bearing steel and the above-mentioned anti-friction composite material as a friction pair, and is obtained by adding a lubricant.

[0009] Furthermore, the lubricant is 15 # Aviation hydraulic fluid.

[0010] Furthermore, the bearing steel is GCr15 bearing steel.

[0011] An application of a friction-reducing composite material in mechanical dynamic seals.

[0012] This invention utilizes an adhesive to bond a PI (polyimide) film to substrates of different polymer materials. Surface modification of polyetheretherketone (PEEK) or polytetrafluoroethylene (PTFE), originally used as sealing materials, yields a friction-reducing composite material. This composite material is then used as a friction pair with bearing steel, and 15% of the material is added... # Aviation hydraulic oil, as a lubricant, can modify the surface properties of the original PEEK or PTFE system under test conditions, so that the new friction system is in a super-lubricating state, thus achieving the purpose of designing new friction-reducing or even super-lubricating seals.

[0013] Select 15 # The main reason why aviation hydraulic oil is used as the lubricant in this system is that this type of hydraulic oil can not only be used in aircraft hydraulic systems for energy transfer, conversion, and control, playing a role in anti-wear, lubrication, corrosion prevention, and rust prevention, ensuring the normal operation of the system and extending equipment life, but also as the working fluid in other high-performance hydraulic systems, such as military transport vehicles, tanks, precision CNC machine tools, high-pressure ethylene transfer pumps, large ship cranes, radar, excavators, aircraft manufacturing machinery, high-speed railways, and ultra-high voltage electrical switches. Even due to 15... # Aviation hydraulic fluid also has an extremely low pour point, making it suitable for use in the aforementioned equipment in extremely cold regions and a substitute for cooling oil. (i.e., 15) # Aviation hydraulic fluid meets the high requirements of reliability and precision in many hydraulic systems. It is a hydraulic fluid with excellent comprehensive performance and can be widely used in various mechanical equipment. Attached Figure Description

[0014] Figure 1 The curves showing the change of friction coefficient over time between the modified polyetheretherketone and bearing steel system under different loads are shown.

[0015] Figure 2 The curves showing the change of friction coefficient over time between the modified polytetrafluoroethylene and bearing steel system under different loads according to the present invention are shown.

[0016] Figure 3 The curves showing the change of friction coefficient over time between the modified polyetheretherketone and bearing steel system at different rotational speeds are shown.

[0017] Figure 4 The curves showing the change of friction coefficient between the modified polytetrafluoroethylene and bearing steel system at different rotation speeds according to the present invention are as follows:

[0018] Figure 5 The curves showing the change of friction coefficient between the modified nitrile rubber and bearing steel system at different rotational speeds according to the present invention are as follows:

[0019] Figure 6 This is a graph showing the change in the coefficient of friction over time between the unmodified polyetheretherketone, nitrile rubber, or polytetrafluoroethylene and the bearing steel system in the comparative examples of this invention. Detailed Implementation

[0020] The technical solutions of the present invention will now be clearly and completely described in conjunction with specific embodiments and accompanying drawings.

[0021] In the following examples, a UTM-3 micro-friction testing machine (Brück, Germany) was used for micro-friction testing. During the test, the test temperature was 25°C. A GCr15 steel ball (4.76 mm in diameter) with a flat surface polished to a diameter of 2.2-2.4 mm was used as the static specimen. A PMDA-ODA type polyimide material (0.127 mm thick) was attached to a fixed disk as the rotating disk specimen, rotating clockwise at a corresponding speed. The radius of the annular friction path was 8.5 mm. The test load was applied perpendicularly through the centerline of the ball specimen, and the test was conducted in a surface-to-surface contact mode. 0.1-0.2 mL of GCr15 was dropped between the two contact surfaces. # Aviation hydraulic oil was used as the lubricant. During the test, the coefficient of friction (COF) was automatically recorded by a computer, and then the average coefficient of friction was calculated by software.

[0022] Example 1

[0023] PI films were bonded to different substrates using acrylic AB glue to obtain modified PEEK and modified PTFE systems, respectively. The friction coefficients of the modified systems under different loads and rotational speeds were then tested.

[0024] Friction tests were conducted under different loads. Each test cycle lasted 3600 seconds, with a rotation speed of 200 rpm and an initial load of 5 N. Each cycle lasted 3600 seconds, and the load was increased by 10 N for each subsequent cycle. The test was terminated when the attached PI film ruptured.

[0025] The average friction coefficient of the modified friction system is as follows: Figure 1 and Figure 2 As shown in Table 1, under the test conditions, both the modified PEEK and modified PTFE friction systems exhibited superlubricity. Furthermore, if the substrate was PEEK, the system could be loaded up to 85 N without becoming superlubricated; further loading caused the surface PI film to rupture. If the substrate was PTFE, the system could only be loaded up to 55 N, maintaining superlubricity, but further loading caused the PI film to rupture. It can be inferred that different substrates used as sealants, after similar surface modifications, will result in different frictional properties and material durability when used as sealants.

[0026] Table 1 Average friction coefficient of the friction system

[0027]

[0028] Friction tests were conducted at different speeds. Each test cycle lasted 3600 seconds, with a load of 5 N and an initial speed of 50 rpm. The speed was increased by 50 rpm in each subsequent cycle until it reached 400 rpm.

[0029] The average friction coefficient of the modified friction system is as follows: Figure 3 and Figure 4 As shown in Table 2, under the test conditions, when the rotational speed is greater than or equal to 100 rpm, the friction system of modified PEEK is in a superlubricated state. Figure 3 When the rotational speed is greater than or equal to 150 rpm, the friction system of modified PTFE is in a superlubricated state (Table 2). Figure 4 ).

[0030] Compared with the modified nitrile rubber system, the PI film was bonded to the nitrile rubber (RUBBRER) using acrylic AB adhesive to obtain the modified nitrile rubber system. None of the modified nitrile rubber systems were in a super-lubricated state (Table 2). Figure 5 Although nitrile rubber is also a commonly used sealing material with its unique mechanical properties, compared to PEEK or PTFE, which are also used as sealing materials, it has lower hardness and higher elasticity. As a substrate for friction systems, it is not conducive to the occurrence of super-lubrication. Therefore, nitrile rubber seals are not suitable for this type of super-lubrication design.

[0031] Table 2 Average friction coefficient of the friction system

[0032]

[0033] Example 2

[0034] The PI film was bonded to different substrates using SH-916 adhesive, and the friction coefficient of the system under different loads and rotational speeds was measured.

[0035] Friction tests were conducted at different speeds. Each test cycle lasted 3600 seconds, with a load of 5 N and an initial speed of 50 rpm. The speed was increased by 50 rpm in each subsequent cycle until it reached 400 rpm.

[0036] The results are shown in Table 3. Under the test conditions, the modified PEEK system was in a superlubricated state under all test conditions except for a friction coefficient of 0.03671 at 50 rpm; the modified PTFE system was also in a superlubricated state. In contrast, the modified nitrile rubber system showed a decrease in friction coefficient at speeds greater than or equal to 150 rpm, but still did not achieve superlubricity.

[0037] Table 3 Average friction coefficient of the friction system

[0038]

[0039] Comparative Example

[0040] Friction behavior test of unmodified polyetheretherketone, nitrile rubber or polytetrafluoroethylene with bearing steel.

[0041] Surface-to-surface friction tests were conducted at a rotational speed of 200 rpm and an initial load of 5 N for 3600 s. The friction pairs were GCr15 steel / PEEK, GCr15 steel / RUBBER, and GCr15 steel / PTFE.

[0042] The test results are shown in Table 4 and Figure 6 As shown. When 15 # When aviation hydraulic oil is used as a lubricant, under the test conditions, the coefficient of friction is about 0.04 when GCr15 steel / PEEK and GCr15 steel / RUBBER are used as friction pairs, and the coefficient of friction is about 0.01 when GCr15 steel / PTFE is used as a friction pair.

[0043] Table 4 Average friction coefficient of the friction system

[0044]

[0045]

[0046] The above experiments demonstrate that polyetheretherketone (PEEK) or polytetrafluoroethylene (PTFE), originally used as sealing materials, can be surface-modified to obtain a friction-reducing composite material. When this composite material is used as a friction pair with bearing steel, 15% of the material can be added... # Aviation hydraulic oil, as a lubricant, can achieve a stable friction coefficient as low as 0.001 under test conditions, resulting in ultra-low friction. Moreover, the friction coefficient of the system is still low after long-term use, thus obtaining a new type of friction-reducing or even super-lubricating system that can be applied to the design and preparation of seals.

[0047] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A friction-reducing composite material, characterized in that, It includes a polymer substrate and a polyimide film adhered to the polymer substrate, wherein the polymer substrate is polyetheretherketone or polytetrafluoroethylene.

2. The friction-reducing composite material according to claim 1, characterized in that, The polyimide film is a PMDA-ODA type polyimide film.

3. The friction-reducing composite material according to claim 1, characterized in that, The polyimide film is adhered to the polymer substrate using SH-916 adhesive or acrylic AB adhesive.

4. A superlubricating system, characterized in that, The friction pair is obtained by using bearing steel and the anti-friction composite material as described in claim 1, and adding a lubricant.

5. A superlubricating system according to claim 4, characterized in that, The lubricant is 15 # Aviation hydraulic fluid.

6. The superlubricating system according to claim 4, characterized in that, The bearing steel is GCr15 bearing steel.

7. An application of a friction-reducing composite material according to claim 1 or 2, characterized in that: Applications in the manufacture of mechanical dynamic seals.

Images