Graphene-based electric control lubricating material and preparation method thereof
The preparation of graphene-based electro-controlled lubricating materials has solved the problem of the uncontrollable friction coefficient of existing lubricating materials in high-end mechanical systems, achieving a macroscopic super-lubricating effect. It is suitable for conventional metal friction pairs and rolling bearings, and has the characteristics of low cost and environmental friendliness.
Patent Information
- Application Number
- CN202511634632.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-10
- Publication Date
- 2026-02-03
AI Technical Summary
Existing lubricating materials have unadjustable friction coefficients in high-end mechanical systems, making them unsuitable for complex working conditions. Furthermore, their production processes are complex, costly, and pose significant environmental risks, making it difficult to achieve in-situ control of friction conditions.
Using graphene-based electro-lubricating materials, including base oil and graphene additives, a lubricating material suitable for macroscopic working conditions is prepared through simple physical mixing and ultrasonic dispersion. The friction state can be reversibly switched by applying a bias voltage.
It achieves stable super-lubricating effect on a macroscopic scale, with a friction coefficient ≤0.01. The material is simple, readily available, and inexpensive, making it suitable for conventional metal friction pairs and rolling bearings, and has industrial application value.
Smart Images
Figure CN121450375A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a graphene-based electro-lubricating material and its preparation method, belonging to the field of tribology. Background Technology
[0002] In high-end mechanical systems, such as aerospace equipment, advanced CNC machine tools, and cutting-edge medical equipment, the performance of core moving parts (such as various bearings) directly determines the precision, efficiency, and reliability of the entire machine. These bearing systems not only require extremely low coefficients of friction to improve energy efficiency and lifespan, but also urgently need stable lubrication and near-constant frictional torque to meet the stringent requirements of high-precision control and smooth operation. Achieving in-situ control of friction behavior or friction state without removing or replacing the lubricating material in the contact area is a major challenge currently facing the field of tribology. Current mainstream mineral-based or synthetic-based lubricants have significant limitations in this regard. Their production processes are complex and costly, and they pose potential environmental risks. More importantly, their lubrication performance (coefficient of friction is typically around 0.1) lacks adjustability and cannot proactively adapt to the complex and changing operating conditions of bearings in response to external commands. Therefore, developing new lubricating materials that combine environmental friendliness, ultra-low coefficient of friction, and excellent electro-friction performance is of paramount importance for developing next-generation intelligent bearing technology and improving the performance of high-end mechanical systems.
[0003] Tan et al. used two specific macrocyclic molecules (4B2A and 3B2A, macrocyclic molecules composed of benzene rings and acetylene groups / linking units) to self-assemble on a solid surface to form a regular porous structure similar to a "molecular chessboard" or "molecular fence," which constitutes the main body of the material. They also chemically modified C60 fullerene to obtain a fullerene derivative (Fluorene-C60), which constitutes the guest of the material. The molecular polarity of Fluorene-C60 is the key to the entire technology's ability to achieve electronic control.
[0004] Researchers used a scanning tunneling microscope (STM) with atomic resolution to observe how C60 molecules embed themselves within the pores of macrocyclic molecules, forming host-guest assembly structures. They induced molecular flipping and movement by changing the bias voltage (i.e., electric field) of the STM tip, thereby altering the assembly structure. The researchers found that the arrangement of Fluorene-C60 on the macrocycle was drastically different when a positive and negative bias voltage was applied to the STM tip.
[0005] Researchers used an atomic force microscope (AFM) probe to slide across the assembled molecular film, quantitatively measuring sliding friction by measuring lateral forces and calculating the coefficient of friction. Under positive bias, the coefficient of friction for this host-guest assembly system was approximately 0.0049, reaching a superlubricated state. This means that by simply switching the voltage, a reversible switch between "high friction" and "ultra-low friction" states can be achieved.
[0006] This technical solution is limited to the microscopic scale and cannot achieve macroscopic measurement and control. Furthermore, the materials used are not simple, readily available, or environmentally friendly, making it unsuitable for practical application. Summary of the Invention
[0007] One objective of this invention is to propose a graphene-based electro-lubricating material suitable for macroscopic working conditions. This lubricating material can be used in key basic components such as rolling bearings and has advantages such as low coefficient of friction, good wear resistance, good electro-friction performance, simple and readily available raw materials, low cost, and green and pollution-free properties.
[0008] The technical solution of this invention is: A graphene-based electro-lubricating material, comprising a base oil and graphene; The base oil is one of mixture 1, mixture 2, polyalphaolefin, perfluoropolyether, and polyethylene glycol; The mixture 1 comprises polyethylene glycol, polytetrafluoroethylene micro powder, and acetone; Mixture 2 comprises deionized water and polyethylene glycol; The polyalphaolefin is specifically PAO8; Graphene-based products include one of the following: graphene nanosheet powder, graphene oxide aqueous dispersion, fluorinated graphene nanosheet powder, and hydroxylated graphene nanosheet powder.
[0009] When the base oil is mixture 1, the graphene is graphene nanosheet powder; When the base oil is mixture 2, the graphene is an aqueous dispersion of graphene oxide; When the base oil is a polyalphaolefin, the graphene is in the form of graphene nanosheet powder. When the base oil is perfluoropolyether, the graphene is fluorinated graphene nanosheet powder; When the base oil is polyethylene glycol, the graphene is hydroxylated graphene nanosheet powder; When the base oil is mixture 1 and the graphene is graphene nanosheet powder, the preparation method of the graphene-based electro-lubricating material is as follows: Step 11: Heat the polyethylene glycol until it reaches the set temperature T1, then add polytetrafluoroethylene micro powder to the polyethylene glycol. After all the powder is added, add acetone reagent and mix well to obtain mixture A. Step 12: Heat the mixture A obtained in step 11 until the temperature reaches the set temperature T2 and then keep it at that temperature to evaporate the acetone and obtain mixture B. Step 13: Add the same amount of polyethylene glycol as in Step 11 to the mixture B obtained in Step 12, cool to room temperature, and then grind it three times or more using a three-roll mill to obtain the basic grease. Step 14: Add graphene nanosheet powder to the base grease obtained in step 13, and grind it three times or more using a three-roll mill to obtain polytetrafluoroethylene-0.2% graphene electronic control grease. In step 11, an oil bath is used for heating, and the temperature T1 is set to 35-45 ℃. The mass ratio of polyethylene glycol, polytetrafluoroethylene micro powder and acetone is 6:4:1. In step 12, the temperature T2 is set to be no lower than 80°C and the heat preservation time is no less than 30 minutes. In step 14, the mass ratio of the base grease to the graphene nanosheet powder is 99.8:0.2. The graphene nanosheet powder has a sheet diameter of 1-5 μm, and the graphene mass fraction in polytetrafluoroethylene-0.2% graphene electro-lubricating grease is 0.2%.
[0010] When the base oil is mixture 2, the graphene is an aqueous dispersion of graphene oxide, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 21: Add deionized water to the graphene oxide aqueous dispersion for dilution and treat with ultrasound to obtain an aqueous solution of graphene oxide. Step 22: Add polyethylene glycol to the aqueous solution of graphene oxide obtained in step 21 to obtain mixture C; Step 23: The mixture C obtained in step 22 is subjected to ultrasonic treatment at a set temperature T3 to obtain polyethylene glycol-graphene oxide electro-controlled lubricating fluid.
[0011] In step 21, the concentration of the graphene oxide aqueous dispersion is 2 mg / mL, and the mass ratio of the graphene oxide aqueous dispersion to deionized water is 1:3, 1:1, 3:1 and without deionized water, respectively. The mass fraction of graphene oxide in the obtained graphene oxide aqueous solution is 0.5‰, 1‰, 1.5‰ and 2‰, respectively. In step 22, the mass ratio of the graphene oxide aqueous solution to polyethylene glycol is 1:9; In step 23, the temperature T3 is set to 35-45 ℃, the ultrasonic treatment time is not less than 30 minutes, and the mass fraction of graphene oxide in the obtained polyethylene glycol-graphene oxide electro-controlled lubricating fluid is 0.05‰, 0.1‰, 0.15‰ and 0.2‰, respectively.
[0012] When the base oil is a polyalphaolefin, the graphene is in the form of graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 31: Add graphene nanosheet powder to polyalphaolefin to obtain mixture D; Step 32: The mixture D obtained in step 31 is subjected to ultrasonic treatment at a set temperature T4 to obtain polyalphaolefin-1% graphene electro-controlled lubricant.
[0013] In step 31, the graphene nanosheet powder has a sheet diameter of 1-5 μm and the mass ratio of graphene nanosheet powder to polyalphaolefin is 1:99. In step 32, the temperature T4 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
[0014] When the base oil is a perfluoropolyether, the graphene is a fluorinated graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 41: Fluorinated graphene nanosheet powder is added to the perfluoropolyether to obtain mixture E; Step 42: The mixture E obtained in step 41 is ultrasonically treated at a set temperature T5 to obtain perfluoropolyether carboxylic acid-0.1% fluorinated graphene electro-lubricating fluid.
[0015] In step 41, the diameter of the fluorinated graphene nanosheet powder is 1-5 μm, and the mass ratio of the fluorinated graphene nanosheet powder to the perfluoropolyether is 1:999. In step 42, the temperature T5 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
[0016] When the base oil is polyethylene glycol, the graphene is hydroxylated graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 51: Add hydroxylated graphene nanosheet powder to polyethylene glycol to obtain mixture F; Step 52: The mixture F obtained in step 51 is ultrasonically treated at a set temperature T6 to obtain polyethylene glycol-0.1% hydroxylated graphene electro-lubricating fluid.
[0017] In step 51, the diameter of the hydroxylated graphene nanosheet powder is 1-5 μm, and the mass ratio of the hydroxylated graphene nanosheet powder to polyethylene glycol is 1:999. In step 52, the temperature T6 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
[0018] Beneficial effects Graphene-based electro-lubricating materials consist of base oils and graphene-based additives. Base oils include, but are not limited to, polyethylene glycol, perfluoropolyether carboxylic acid, and polyalphaolefins; graphene includes, but is not limited to, graphene, fluorinated graphene, graphene oxide, hydroxylated graphene, carboxylated graphene, and aminographene. Graphene-based electro-lubricating materials can be classified as either lubricating oils or greases, depending on the application requirements. Graphene-based electro-lubricating materials can achieve super-lubricity under macroscopic conditions. Graphene-based electro-lubricating materials can be used in rolling bearings.
[0019] Moving from the microscopic to the macroscopic, achieving macroscopic-scale electronically controlled superlubricity. Tan et al.'s technique heavily relies on precision instruments such as STM and AFM, limiting its operation and observation to extremely small contact areas at the nanometer or micrometer scale, essentially representing a laboratory-level demonstration of microscopic phenomena. This invention completely breaks through this scale limitation, achieving stable and repeatable superlubricity (friction coefficient ≤0.01) on macroscopic steel ball / disc friction pairs. This elevates the technology from the realm of basic research to a stage with practical engineering applications.
[0020] The material system is simple and inexpensive, and has great potential for industrialization. Tan et al.'s technique requires the synthesis of two macrocyclic molecules with specific structures (4B2A / 3B2A) and complex chemical modification of the fullerene (Fluorene-C60). Its raw material preparation process is cumbersome, extremely costly, and difficult to scale up. In contrast, the base oil and graphene used in this invention are commercially available, readily available industrial raw materials, inexpensive, and of stable origin. The preparation method involves only simple physical mixing and ultrasonic dispersion, making the process extremely simple and highly suitable for large-scale formulation and production, laying the foundation for practical application.
[0021] More suitable for actual mechanical working conditions Tan et al.'s technology requires assembly on highly controllable, atomically flat surfaces, placing extremely stringent demands on the environment and substrate. The graphene-based electro-lubricating material of this invention can be directly applied to conventional metal friction pairs (such as steel / steel), maintaining excellent low-friction conditions within a certain load range (2~16 N) and speed range (12.5~250 mm / s), demonstrating stronger adaptability and robustness to actual working conditions. Furthermore, the graphene-based electro-lubricating material of this invention can be used in key basic components such as rolling bearings, possessing industrial application value.
[0022] The electronic control mechanism is simple and easy to integrate. Existing electro-control mechanisms rely on altering the polarity of individual molecules and their precise arrangement on a molecular chessboard, which is complex to implement. The electro-controlled friction effect of this invention can be achieved by applying a simple bias voltage (e.g., -0.6 V) to the friction pair, without the need to construct complex molecular assembly layers. The control logic is simple and easier to integrate into existing mechanical or electromechanical systems, enabling active, in-situ intelligent control of the friction state. Attached Figure Description
[0023] Figure 1 The test results are for Example 1; Figure 2 The test results are for Example 2; Figure 3 The test results are for Example 3; Figure 4 The test results are for Example 4; Figure 5 The results are from Example 5. Detailed Implementation
[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.
[0025] Example 1 When the base oil is mixture 1, the graphene is in the form of graphene nanosheet powder. The preparation method of the graphene-based electro-lubricating material is as follows: Step 11: Heat the polyethylene glycol until it reaches the set temperature T1, then add polytetrafluoroethylene micro powder to the polyethylene glycol. After all the powder is added, add acetone reagent and mix well to obtain mixture A. Step 12: Heat the mixture A obtained in step 11 until the temperature reaches the set temperature T2 and then keep it at that temperature to evaporate the acetone and obtain mixture B. Step 13: Add the same amount of polyethylene glycol as in Step 11 to the mixture B obtained in Step 12, cool to room temperature, and then grind it three times or more using a three-roll mill to obtain the basic grease. Step 14: Add graphene nanosheet powder to the base grease obtained in step 13, and grind it three times or more using a three-roll mill to obtain polytetrafluoroethylene-0.2% graphene electronic control grease. In step 11, an oil bath is used for heating, and the temperature T1 is set to 35-45 ℃. The mass ratio of polyethylene glycol, polytetrafluoroethylene micro powder and acetone is 6:4:1. In step 12, the temperature T2 is set to be no lower than 80°C and the heat preservation time is no less than 30 minutes. In step 14, the mass ratio of the base grease to the graphene nanosheet powder is 99.8:0.2. The graphene nanosheet powder has a sheet diameter of 1-5 μm, and the graphene mass fraction in polytetrafluoroethylene-0.2% graphene electro-lubricating grease is 0.2%.
[0026] Example 2 When the base oil is mixture 2, the graphene is an aqueous dispersion of graphene oxide. The preparation method of the graphene-based electro-lubricating material is as follows: Step 21: Add deionized water to the graphene oxide aqueous dispersion for dilution and treat with ultrasound to obtain an aqueous solution of graphene oxide. Step 22: Add polyethylene glycol to the aqueous solution of graphene oxide obtained in step 21 to obtain mixture C; Step 23: The mixture C obtained in step 22 is subjected to ultrasonic treatment at a set temperature T3 to obtain polyethylene glycol-graphene oxide electro-controlled lubricating fluid.
[0027] In step 21, the concentration of the graphene oxide aqueous dispersion is 2 mg / mL, and the mass ratio of the graphene oxide aqueous dispersion to deionized water is 1:3, 1:1, 3:1 and without deionized water, respectively. The mass fraction of graphene oxide in the obtained graphene oxide aqueous solution is 0.5‰, 1‰, 1.5‰ and 2‰, respectively. In step 22, the mass ratio of the graphene oxide aqueous solution to polyethylene glycol is 1:9; In step 23, the temperature T3 is set to 35-45 ℃, the ultrasonic treatment time is not less than 30 minutes, and the mass fraction of graphene oxide in the obtained polyethylene glycol-graphene oxide electro-controlled lubricating fluid is 0.05‰, 0.1‰, 0.15‰ and 0.2‰, respectively.
[0028] Example 3 When the base oil is a polyalphaolefin, the graphene is in the form of graphene nanosheet powder. The preparation method of the graphene-based electro-lubricating material is as follows: Step 31: Add graphene nanosheet powder to polyalphaolefin to obtain mixture D; Step 32: The mixture D obtained in step 31 is subjected to ultrasonic treatment at a set temperature T4 to obtain polyalphaolefin-1% graphene electro-controlled lubricant.
[0029] In step 31, the graphene nanosheet powder has a sheet diameter of 1-5 μm and the mass ratio of graphene nanosheet powder to polyalphaolefin is 1:99. In step 32, the temperature T4 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
[0030] Example 4 When the base oil is a perfluoropolyether, the graphene is fluorinated graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 41: Fluorinated graphene nanosheet powder is added to the perfluoropolyether to obtain mixture E; Step 42: The mixture E obtained in step 41 is ultrasonically treated at a set temperature T5 to obtain perfluoropolyether carboxylic acid-0.1% fluorinated graphene electro-lubricating fluid.
[0031] In step 41, the diameter of the fluorinated graphene nanosheet powder is 1-5 μm, and the mass ratio of the fluorinated graphene nanosheet powder to the perfluoropolyether is 1:999. In step 42, the temperature T5 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
[0032] Example 5 When the base oil is polyethylene glycol, the graphene is hydroxylated graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 51: Add hydroxylated graphene nanosheet powder to polyethylene glycol to obtain mixture F; Step 52: The mixture F obtained in step 51 is ultrasonically treated at a set temperature T6 to obtain polyethylene glycol-0.1% hydroxylated graphene electro-lubricating fluid.
[0033] In step 51, the diameter of the hydroxylated graphene nanosheet powder is 1-5 μm, and the mass ratio of the hydroxylated graphene nanosheet powder to polyethylene glycol is 1:999. In step 52, the temperature T6 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
[0034] The friction coefficient of the obtained graphene-based electro-lubricating material was tested. Friction coefficient measurement conditions and methods: The coefficient of friction and frictional torque of graphene-based electro-lubricating materials were determined using a multi-functional friction and wear testing machine (UMT-3) in ball-and-disc contact and rolling bearings, respectively. The instrument was cleaned and calibrated before measurement to ensure the accuracy of the results. Test conditions were a room temperature of approximately 25 ℃ and an ambient relative humidity of 20%–40%.
[0035] Ball-disc contact: The friction pair consists of a steel ball and a steel disc, both made of bearing steel. The steel ball has a diameter of 10 mm and a surface roughness of 10 nm, while the steel disc has a surface roughness of 25 nm. Before testing, an appropriate amount of electrically controlled lubricating material is added between the steel ball and the steel disc. The load range between the steel ball and the steel disc is 2~16 N, and the relative sliding speed between the steel ball and the steel disc is 12.5~250 mm / s.
[0036] Rolling bearing: Before testing, add an appropriate amount of electronically controlled lubricating material to the 7005 bearing, apply an axial load of 10 N to the bearing, rotate the outer ring while keeping the inner ring stationary, and rotate at a speed of 500 r / min.
[0037] The polytetrafluoroethylene-0.2% graphene electro-controlled grease obtained in Example 1: After using this grease to lubricate the steel balls and steel discs, the test results are as follows: Figure 1 As shown, according to Figure 1 It can be seen that the obtained product achieves stable lubrication at a voltage of 2 V.
[0038] The polyethylene glycol-graphene oxide electro-controlled lubricating fluid obtained in Example 2 After lubricating the steel ball and steel disc with polyethylene glycol-0.2‰ graphene oxide electro-controlled lubricant for 7200 seconds, the test results are as follows. Figure 2 As shown in (a); after changing the mass fraction of graphene oxide in the above-mentioned electro-lubricating material to 0.05‰, 0.1‰, and 0.15‰ respectively, and then lubricating the steel ball and steel disc, the test results are as follows. Figure 2 As shown in (b); after lubricating steel balls and steel discs with polyethylene glycol-0.2‰ graphene oxide electro-controlled lubricant under loads of 2~16 N, the test results are as follows. Figure 2 As shown in (c); after lubricating the steel ball and steel disc with polyethylene glycol-0.2‰ graphene oxide electro-controlled lubricant at a sliding speed of 12.5~250 mm / s, the test results are as follows. Figure 2 As shown in (d), according to Figure 2 It can be seen that the obtained product achieves stable superlubricity under the conditions of normal load of 2~4 N and sliding speed of about 100 mm / s.
[0039] The polyalphaolefin-1% graphene electro-controlled lubricant obtained in Example 3 After lubricating a steel ball and a steel disc with this lubricant for 3600 seconds under electrical stimulation at 0 V, -5 V, and -25 V respectively, the test results are as follows. Figure 3 As shown, according to Figure 3 It can be seen that the obtained product achieves stable lubrication when a load of 3 A is applied.
[0040] The perfluoropolyether carboxylic acid-0.1% fluorinated graphene electro-lubricating fluid obtained in Example 4 After lubricating a steel ball and a steel disc with this lubricant for 9000 seconds under electrical stimulation at 0 V and -25 V respectively, the test results are as follows. Figure 4 As shown, according to Figure 4 It can be seen that the obtained product achieves stable lubrication when a load of 3 A is applied.
[0041] The polyethylene glycol-0.1% hydroxylated graphene electro-lubricating fluid obtained in Example 5 After lubricating a steel ball and a steel disc with this lubricant for 9000 seconds under electrical stimulation at 0 V and -25 V respectively, the test results are as follows. Figure 5 As shown, according to Figure 5 It can be seen that the obtained product achieves stable lubrication when a load of 3 A is applied.
[0042] Finally, it is necessary to note that the above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited thereto. Any modifications or substitutions made by those skilled in the art based on the technical content disclosed in the present invention to achieve equivalent functions and effects should be covered within the scope of protection of the present invention. These modifications include, but are not limited to: the types of materials such as base oil, graphene, and lubricating grease; working conditions such as electrical signals, loads, speed, temperature, humidity, types of metal friction pairs, and types of rolling bearings; and process conditions such as solution ratio, preparation method, dosage, and application method.
[0043] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A graphene-based electro-lubricating material, characterized in that: The lubricating material includes base oils and graphene-based materials; The base oil is one of mixture 1, mixture 2, polyalphaolefin, perfluoropolyether, and polyethylene glycol; The mixture 1 comprises polyethylene glycol, polytetrafluoroethylene micro powder, and acetone; Mixture 2 comprises deionized water and polyethylene glycol; The polyalphaolefin is specifically PAO8; Graphene-based products include one of the following: graphene nanosheet powder, graphene oxide aqueous dispersion, fluorinated graphene nanosheet powder, and hydroxylated graphene nanosheet powder.
2. The graphene-based electro-lubricating material according to claim 1, characterized in that: When the base oil is mixture 1, the graphene is in the form of graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 11: Heat the polyethylene glycol until it reaches the set temperature T1, then add polytetrafluoroethylene micro powder to the polyethylene glycol. After all the powder is added, add acetone reagent and mix well to obtain mixture A. Step 12: Heat the mixture A obtained in step 11 until the temperature reaches the set temperature T2 and then keep it at that temperature to evaporate the acetone and obtain mixture B. Step 13: Add the same amount of polyethylene glycol as in Step 11 to the mixture B obtained in Step 12, cool to room temperature, and then grind it three times or more using a three-roll mill to obtain the basic grease. Step 14: Add graphene nanosheet powder to the base grease obtained in step 13, and grind it three times or more using a three-roll mill to obtain polytetrafluoroethylene-0.2% graphene electronic control grease. In step 11, an oil bath is used for heating, and the temperature T1 is set to 35-45 ℃. The mass ratio of polyethylene glycol, polytetrafluoroethylene micro powder and acetone is 6:4:
1. In step 12, the temperature T2 is set to be no lower than 80°C and the heat preservation time is no less than 30 minutes. In step 14, the mass ratio of the base grease to the graphene nanosheet powder is 99.8:0.
2. The graphene nanosheet powder has a sheet diameter of 1-5 μm, and the graphene mass fraction in polytetrafluoroethylene-0.2% graphene electro-lubricating grease is 0.2%.
3. The graphene-based electro-lubricating material according to claim 1, characterized in that: When the base oil is mixture 2, the graphene is an aqueous dispersion of graphene oxide. The preparation method of the graphene-based electro-lubricating material is as follows: Step 21: Add deionized water to the graphene oxide aqueous dispersion for dilution and treat with ultrasound to obtain an aqueous solution of graphene oxide. Step 22: Add polyethylene glycol to the aqueous solution of graphene oxide obtained in step 21 to obtain mixture C; Step 23: The mixture C obtained in step 22 is subjected to ultrasonic treatment at a set temperature T3 to obtain polyethylene glycol-graphene oxide electro-controlled lubricating fluid. In step 21, the concentration of the graphene oxide aqueous dispersion is 2 mg / mL, and the mass ratio of the graphene oxide aqueous dispersion to deionized water is 1:3, 1:1, 3:1 and without deionized water, respectively. The mass fraction of graphene oxide in the obtained graphene oxide aqueous solution is 0.5‰, 1‰, 1.5‰ and 2‰, respectively. In step 22, the mass ratio of the graphene oxide aqueous solution to polyethylene glycol is 1:9; In step 23, the temperature T3 is set to 35-45 ℃, the ultrasonic treatment time is not less than 30 minutes, and the mass fraction of graphene oxide in the obtained polyethylene glycol-graphene oxide electro-controlled lubricating fluid is 0.05‰, 0.1‰, 0.15‰ and 0.2‰, respectively.
4. The graphene-based electro-lubricating material according to claim 1, characterized in that: When the base oil is polyalphaolefin, the graphene is in the form of graphene nanosheet powder. The preparation method of graphene-based electro-lubricating materials is as follows: Step 31: Add graphene nanosheet powder to polyalphaolefin to obtain mixture D; Step 32: The mixture D obtained in step 31 is subjected to ultrasonic treatment at a set temperature T4 to obtain polyalphaolefin-1% graphene electro-controlled lubricant. In step 31, the graphene nanosheet powder has a sheet diameter of 1-5 μm and the mass ratio of graphene nanosheet powder to polyalphaolefin is 1:
99. In step 32, the temperature T4 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
5. The graphene-based electro-lubricating material according to claim 1, characterized in that: When the base oil is perfluoropolyether, the graphene is fluorinated graphene nanosheet powder, and the preparation method of graphene-based electro-lubricating materials is as follows: Step 41: Fluorinated graphene nanosheet powder is added to the perfluoropolyether to obtain mixture E; Step 42: The mixture E obtained in step 41 is ultrasonically treated at a set temperature T5 to obtain perfluoropolyether carboxylic acid-0.1% fluorinated graphene electro-lubricating fluid. In step 41, the diameter of the fluorinated graphene nanosheet powder is 1-5 μm, and the mass ratio of the fluorinated graphene nanosheet powder to the perfluoropolyether is 1:
999. In step 42, the temperature T5 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.
6. The graphene-based electro-lubricating material according to claim 1, characterized in that: When the base oil is polyethylene glycol, the graphene is hydroxylated graphene nanosheet powder, and the preparation method of the graphene-based electro-lubricating material is as follows: Step 51: Add hydroxylated graphene nanosheet powder to polyethylene glycol to obtain mixture F; Step 52: The mixture F obtained in step 51 is ultrasonically treated at a set temperature T6 to obtain polyethylene glycol-0.1% hydroxylated graphene electro-lubricating fluid. In step 51, the diameter of the hydroxylated graphene nanosheet powder is 1-5 μm, and the mass ratio of the hydroxylated graphene nanosheet powder to polyethylene glycol is 1:
999. In step 52, the temperature T6 is set to 35-45 ℃, and the ultrasonic treatment time is not less than 30 minutes.