A method for preparing graphene carbon nanoparticle lubricating oil

Abstract

A method for preparing graphene carbon nanoparticle lubricating oil relates to a method for preparing lubricating oil. The preparation method of the invention comprises the following steps: adding graphene to a base oil containing a modifier, stirring on a constant temperature magnetic stirrer, and then placing each group of oil obtained in an ultrasonic machine for ultrasonic oscillation treatment. The prepared graphene lubricating oil is tested for lubrication performance by bearings. Within the added range of the test, the lubricating oil without graphene is better than the lubricating oil with graphene added. And when the mass fraction of the graphene additive is 0.1%, the friction reduction and anti-wear effect is the best. When the stable lubrication stage is reached, the friction coefficient is reduced by 25%, the bearing wear is reduced, and the wear surface morphology of the bearing outer ring is effectively improved.

Description

Technical Field

[0001] The invention relates to a method for preparing lubricating oil, in particular to a method for preparing graphene carbon nanoparticle lubricating oil. Background Art

[0002] With the urgent need for high-end advanced manufacturing equipment, reducing bearing friction loss and extending bearing service life have become key issues that need to be solved in the manufacturing industry. The basic method to reduce friction and wear is to use lubricants. With the continuous progress of tribology research, the research on friction pairs has gradually shifted from macro friction to micro friction. Adding a small amount of nanoparticles with lubricating properties to the original lubricant can significantly improve the anti-wear and friction reduction properties of the lubricant.

[0003] Graphene has excellent mechanical properties, and single-layer or multi-layer graphene has an ultra-thin sheet structure. Current graphene research has found that its excellent self-lubricating properties will have broad application prospects in the field of lubricating additives.

[0004] However, since graphene is a solid particle, its dispersion stability in oil is poor, so it is easy to settle and agglomerate in lubricating oil, which limits its application as a friction-reducing and anti-wear additive. Summary of the invention

[0005] The purpose of the present invention is to provide a method for preparing a graphene carbon nanoparticle lubricant. When the present invention adds lubricants with different mass fractions of graphene additives, the peak values ​​of the friction coefficients of the sample bearings are all lower than those of the base oil lubrication state, the overall value of the friction coefficient is reduced, and the fluctuation is reduced. When the mass fraction of the added graphene is 0.1%, the friction coefficient curve is the most stable and the fluctuation is the smallest. The graphene additive improves the bearing's load-bearing capacity, enters the stable lubrication stage in advance, reduces the bearing wear, and effectively improves the wear surface morphology of the bearing outer ring

[0006] The objective of the present invention is achieved through the following technical solutions:

[0007] A method for preparing graphene carbon nanoparticle lubricating oil, the method comprising the following steps:

[0008] Step S1, taking base oil and heating it in a constant temperature water bath;

[0009] Step S2, adding graphene to base oil, and adding a modifier to the oil;

[0010] Step S3, stirring on a constant temperature magnetic stirrer to obtain oil;

[0011] Step S4: Then, the obtained oil liquid is placed in an ultrasonic machine for ultrasonic vibration treatment to obtain graphene lubricating oil.

[0012] The method for preparing a graphene carbon nanoparticle lubricant oil, wherein the number of graphene layers ranges from 1 to 3 layers, and the sheet diameter is 7 to 12 μm.

[0013] The method for preparing a graphene carbon nanoparticle lubricant oil, wherein the lubricant oil is one or more of a mineral base oil, a synthetic base oil, a commercialized or homemade lubricant oil.

[0014] In the method for preparing a graphene carbon nanoparticle lubricant, the modifier is a mixture of oleic acid and stearic acid for surface modification, and the content of the modifier is 5% of the content of the lubricant.

[0015] In the method for preparing a graphene carbon nanoparticle lubricating oil, the base oil is heated in a constant temperature water bath at a heating temperature of 80°C.

[0016] In the method for preparing graphene carbon nanoparticle lubricating oil, the constant temperature magnetic stirrer has a stirring time of 20 minutes and a rotation speed of 100 npr.

[0017] In the method for preparing graphene carbon nanoparticle lubricating oil, the oil is placed in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes.

[0018] In the method for preparing graphene carbon nanoparticle lubricating oil, the mass percentage content of the single-layer or multi-layer graphene in the lubricating oil is 0.001-0.2%.

[0019] The advantages and effects of the present invention are:

[0020] The present invention tests the friction coefficient of the friction pair before reaching the stable lubrication stage. When the lubricating oil with different mass fractions of graphene additives is added, the peak value of the friction coefficient of the sample bearing is lower than that in the base oil lubrication state, the overall value of the friction coefficient is reduced, and the fluctuation is reduced. When the mass fraction of the added graphene is 0.1%, the friction coefficient curve is the most stable and the fluctuation is the smallest. This shows that the graphene additive can improve the load-bearing capacity of the bearing and enter the stable lubrication stage ahead of time.

[0021] When the specimen bearing reaches the stable lubrication stage, the friction coefficient remains unchanged. The average friction coefficient of the specimen bearing under base oil lubrication is 0.012, which is greater than the average friction coefficient of the configured graphene lubricant. The change in the friction coefficient shows an overall trend of increasing first and then decreasing with the increase in the content of graphene additives in the lubricant. When the mass fraction of graphene is 0.1%, the average friction coefficient of the friction pair drops to the minimum value of 0.009, which is 25% lower than the friction coefficient of the friction pair under base oil lubrication. Then, with the increase in the mass fraction of graphene, the friction coefficient increases, but it is still lower than the friction coefficient under base oil lubrication.

[0022] The wear of the bearings was also compared. Compared with base oil lubrication, the wear of the five groups of bearings under the action of graphene additive lubricants was reduced. Among them, the wear was as low as 9.42 mg when the mass fraction of graphene additives was 0.1%, which was 14.52% lower than the wear of the bearings under base oil lubrication. By comparing the wear of the cage and the race, it can be seen that the wear of the cage and the race under base oil lubrication is much greater than the wear under the action of graphene additive lubricants. Among them, when the mass fraction of graphene additives was 0.1%, the wear of the cage could be reduced by up to 40.38%, and the wear of the race could be reduced by up to 24.07%. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a flow chart of an embodiment of the present invention;

[0024] Figure 2 The friction coefficient curves of the friction pairs in different groups of Examples 1-4 of the present invention before reaching the stable lubrication stage;

[0025] Figure 3 The friction coefficient curves of the friction pairs in different groups of Examples 1-4 of the present invention before reaching the stable lubrication stage;

[0026] Figure 4 The friction coefficient values ​​of the rolling bearings lubricated by each oil sample group at 1100s to 7200s in Examples 1-4 of the present invention;

[0027] Figure 5 The wear amount of the bearing shaft ring of the sample with lubricating oil additives of different components in Examples 1-4 of the present invention;

[0028] Figure 6 The wear amount of the bearing cage of the samples of Examples 1-4 of the present invention with lubricating oil additives of different components. Implementation

[0029] The present invention will be described in detail below with reference to the embodiments shown in the accompanying drawings. Example

[0030] The preparation flow chart of the graphene lubricating oil additive of the present invention is as follows Figure 1 and Figure 2 As shown, the method comprises the following steps:

[0031] Take the base oil and heat it to 80°C in a constant temperature water bath. Add graphene to the base oil and add 5% modifier to the oil. Stir for 20 minutes on a constant temperature magnetic stirrer with the speed set to 100 npr to obtain oil. Then place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil. Example

[0032] Step 1: Take the base oil and heat it to 80℃ in a constant temperature water bath;

[0033] Step 2: Add 0.02% by mass of graphene to the base oil, and add 5% of the modifier to the oil;

[0034] Step 3: Stir on a constant temperature magnetic stirrer for 20 min, with the speed set to 100 npr;

[0035] Step 4: Place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil. Example

[0036] Step 1: Take the base oil and heat it to 80℃ in a constant temperature water bath;

[0037] Step 2: Add 0.05% by mass of graphene to the base oil, and add 5% of the modifier to the oil;

[0038] Step 3: Stir on a constant temperature magnetic stirrer for 20 min, with the speed set to 100 npr;

[0039] Step 4: Place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil. Example

[0040] Step 1: Take the base oil and heat it to 80℃ in a constant temperature water bath;

[0041] Step 2: Add 0.05% by mass of graphene to the base oil, and add 5% of the modifier to the oil;

[0042] Step 3: Stir on a constant temperature magnetic stirrer for 20 min, with the speed set to 100 npr;

[0043] Step 4: Place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil. Example

[0044] Step 1: Take the base oil and heat it to 80℃ in a constant temperature water bath;

[0045] Step 2: Add 0.1% by mass of graphene to the base oil, and add 5% of the modifier to the oil;

[0046] Step 3: Stir on a constant temperature magnetic stirrer for 20 min, with the speed set to 100 npr;

[0047] Step 4: Place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil. Example

[0048] Step 1: Take the base oil and heat it to 80℃ in a constant temperature water bath;

[0049] Step 2: Add 0.15% by mass of graphene to the base oil, and add 5% of the modifier to the oil;

[0050] Step 3: Stir on a constant temperature magnetic stirrer for 20 min, with the speed set to 100 npr;

[0051] Step 4: Place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil. Example

[0052] Step 1: Take the base oil and heat it to 80℃ in a constant temperature water bath;

[0053] Step 2: Add 0.2% by mass of graphene to the base oil, and add 5% of the modifier to the oil;

[0054] Step 3: Stir on a constant temperature magnetic stirrer for 20 min, with the speed set to 100 npr;

[0055] Step 4: Place the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes to obtain graphene lubricating oil.

[0056] The graphene lubricants with different mass fractions prepared are as follows: Figure 3 Please refer to Figure 2-Figure 6 This scheme tests the friction coefficient of the friction pair before reaching the stable lubrication stage. When the lubricating oil with different mass fractions of graphene additives is added, the peak value of the friction coefficient of the sample bearing is lower than that of the base oil lubrication state. The overall value of the friction coefficient is reduced and the fluctuation is reduced. When the mass fraction of the added graphene is 0.1%, the friction coefficient curve is the most stable and the fluctuation is the smallest. This shows that the graphene additive can improve the bearing's load-bearing capacity and enter the stable lubrication stage ahead of time.

[0057] When the specimen bearing reaches the stable lubrication stage, the friction coefficient remains unchanged. The average friction coefficient of the specimen bearing under base oil lubrication is 0.012, which is greater than the average friction coefficient of the configured graphene lubricant. The change in the friction coefficient shows an overall trend of increasing first and then decreasing with the increase in the content of graphene additives in the lubricant. When the mass fraction of graphene is 0.1%, the average friction coefficient of the friction pair drops to the minimum value of 0.009, which is 25% lower than the friction coefficient of the friction pair under base oil lubrication. Then, with the increase in the mass fraction of graphene, the friction coefficient increases, but it is still lower than the friction coefficient under base oil lubrication.

[0058] The wear of the bearings was also compared. Compared with base oil lubrication, the wear of the five groups of bearings under the action of graphene additive lubricants was reduced. Among them, the wear was as low as 9.42 mg when the mass fraction of graphene additives was 0.1%, which was 14.52% lower than the wear of the bearings under base oil lubrication. By comparing the wear of the cage and the race, it can be seen that the wear of the cage and the race under base oil lubrication is much greater than the wear under the action of graphene additive lubricants. Among them, when the mass fraction of graphene additives was 0.1%, the wear of the cage could be reduced by up to 40.38%, and the wear of the race could be reduced by up to 24.07%.

Claims

1. A method for preparing graphene carbon nanoparticle lubricating oil, characterized in that: The method comprises the following steps: Step S1, taking base oil and heating it in a constant temperature water bath; Step S2, adding graphene to base oil, and adding a modifier to the oil; the number of graphene layers ranges from 1 to 3 layers, and the sheet diameter is 7 to 12 μm; the mass percentage content of the single-layer or multi-layer graphene in the lubricating oil is 0.001 to 0.2%; Step S3, stirring on a constant temperature magnetic stirrer to obtain oil; Step S4, then placing the obtained oil in an ultrasonic machine for ultrasonic oscillation treatment to obtain graphene lubricating oil; The lubricating oil is one or more of mineral base oil, synthetic base oil, commercial or homemade lubricating oil; The modifier is a mixture of oleic acid and stearic acid for surface modification, and the content of the modifier is 5% of the lubricating oil content; The base oil is heated in a constant temperature water bath at a temperature of 80°C; The constant temperature magnetic stirrer is stirred for 20 minutes and the speed is set to 100 npr; The oil is placed in an ultrasonic machine for ultrasonic oscillation treatment for 30 minutes.

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