Galvanized metal forming lubricating oil and preparation method thereof

Abstract

The invention relates to the technical field of lubricating oil, and discloses galvanized metal forming lubricating oil and a preparation method thereof.The lubricating oil is prepared from, by mass, 10%-15% of a modified graphene lubricating agent, 8%-12% of an oiliness agent, 5%-10% of an anti-rust agent, 0.1%-0.5% of a corrosion inhibition additive, 0.1%-0.3% of an antioxidant and the balance base oil and inevitable impurities; the modified graphene lubricant is obtained by modifying graphene oxide with enamine; the preparation method comprises the following steps: adding the modified graphene lubricant, the oiliness agent, the antirust agent, the corrosion inhibition additive, the antioxidant and the base oil into a container, and uniformly stirring at 55-60 DEG C to obtain the galvanized metal forming lubricating oil. The modified graphene is obtained through enamine modified graphene oxide, the indissolvable property of graphene in an organic solvent can be improved, and the modified graphene is added into the galvanized metal forming lubricating oil, so that the stability of the lubricating oil is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of lubricating oils, and in particular relates to a galvanized metal forming lubricating oil and a preparation method thereof. Background Art

[0002] Galvanized metal forming lubricant is a specialized lubricant used in metal forming processes (such as cold rolling, hot-dip galvanizing, and stamping). Its primary function is to reduce friction between the metal and the mold, preventing adhesive wear. It also provides cooling, rust prevention, and cleaning properties. Its performance directly impacts processing efficiency, product quality, and mold life.

[0003] Galvanized metals are sensitive to sulfur-containing lubricants due to the zinc coating on their surfaces. This is primarily due to a chemical reaction between sulfur and zinc, which can lead to corrosion of the coating, mold wear, and reduced product quality. Consequently, the use of sulfur-containing lubricants in forming lubricants for galvanized metals is significantly limited. Graphene, a single-atomic-layer, two-dimensional carbon nanomaterial, possesses excellent electrical and thermal conductivity, as well as lubricity. Compared to non-metallic nanoparticles such as graphite and carbon nanotubes, graphene offers superior anti-wear and friction reduction properties. However, its inherent insolubility in common organic solvents or base oils creates numerous application challenges. Summary of the Invention

[0004] In view of this, the purpose of the present invention is to provide a galvanized metal forming lubricant and a preparation method, wherein modified graphene is obtained by modifying graphene oxide with enamine, which can improve the insolubility of graphene in organic solvents. The modified graphene is added to the galvanized metal forming lubricant to improve the stability of the lubricant.

[0005] The present invention solves the above technical problems through the following technical means:

[0006] In the first aspect, the present application discloses a galvanized metal forming lubricant, which comprises the following raw materials, by mass percentage: 10-15% modified graphene lubricant, 8-12% oiliness agent, 5-10% rust inhibitor, 0.1-0.5% corrosion inhibitor, 0.1-0.3% antioxidant, and the balance is base oil and unavoidable impurities; the modified graphene lubricant is obtained by enamine-modified graphene oxide.

[0007] Furthermore, the enamine is any one of hexadecenamine, octadecenamine, eicoseneamine, 3-methylhexadecenamine, and 1-methyloctadecenamine, or a combination thereof.

[0008] Furthermore, the oiliness agent is any one or a combination of low-erucic acid rapeseed oil, hydrogenated lard, trimethylolpropane ester, dipentaerythritol ester, isooctanoic acid diester, pentaerythritol ester, and tetrakis(3-mercaptobutyric acid)pentaerythritol ester; and the rust inhibitor is any one or a combination of barium dinonylnaphthalene sulfonate, barium petroleum sulfonate, and calcium dinonylnaphthalene sulfonate.

[0009] Furthermore, the antioxidant is any one of thiocarbamate and zinc thiocarbamate or a combination of the two; and the base oil is any one of white oil and engine oil or a combination of the two.

[0010] Furthermore, the corrosion inhibitor additive is an N,N-bis(5-methylbenzotriazole methylene) hexadecylamine metal deactivator. The preparation method of the corrosion inhibitor additive comprises: adding 5-methylbenzotriazole, hexadecylamine, and formaldehyde to a reaction solvent, stirring, and heating to 60-70°C to dissolve; after complete dissolution, raising the temperature to 80-90°C to react; and after completion of the reaction, extracting and separating the product with D60 solvent gasoline to obtain the corrosion inhibitor additive. The corrosion inhibitor additive in this technical solution has higher thermal oxidative stability and better metal deactivation.

[0011] Furthermore, the mass ratio of the 5-methylbenzotriazole, hexadecylamine, and formaldehyde is (1-2): (2-3): (3-4); the reaction solvent is one of a 70-80% ethanol solution, N,N-dimethylformamide, and toluene, and the mass of the reaction solvent is 3-5 times the mass of 5-methylbenzotriazole.

[0012] Furthermore, the preparation method of the modified graphene lubricant includes:

[0013] S1. Dissolve 1 part of graphene oxide in deionized water by mass and ultrasonicate for 20-30 min to form a uniform dispersion.

[0014] S2. Add an acidic substance to the dispersion to adjust the pH of the dispersion to 2-3;

[0015] S3, adding 3-5 parts of enamine dropwise with stirring at 170-190° C., and reacting for 18-30 hours to obtain a paste product;

[0016] S4, filtering the paste product and washing it with anhydrous ethanol to obtain modified graphene;

[0017] S5. Dissolving the modified graphene in 150-250 parts of a solvent ether and a poly-alpha-olefin solvent to obtain a modified graphene lubricant.

[0018] This technical solution reacts graphene oxide with enamine in a specific ratio at a specific temperature for a specific time. During this process, the graphene oxide particles absorb enamine chains of a certain length through electrostatic adsorption, resulting in a stable dispersion. The product is filtered and washed with anhydrous ethanol. The product is then dissolved in a solvent composed of ether and polyalphaolefin to produce a modified graphene lubricant. The modified graphene dispersion has a concentration of 0.15-0.21 g / mL and has been shown to be stable for 5-7 months.

[0019] Furthermore, the solvent ether is one of dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, and ethylene glycol dibutyl ether, or a mixture of several thereof; and the polyalphaolefin is any one of polydecene and polydodecene.

[0020] Furthermore, in step S3, after the enamine is added dropwise, 1 to 3 parts of 3-aminopropyltriethoxysilane is added and stirred evenly; a cathode plate and an anode plate are then placed in the reaction solution. During the reaction, an alternating current of 18 to 36 V and a current of 1 to 2 A is intermittently supplied to the cathode plate and the anode plate, with the intermittent frequency being 15 to 25 minutes on and 15 to 25 minutes off. During the electrostatic adsorption process of the graphene oxide and the enamine, the current is supplied to the reaction solution, and under the action of 3-aminopropyltriethoxysilane, the stability of the electrostatic adsorption of the enamine molecular chain on the graphene oxide particles can be further improved, thereby further improving the stability of the modified graphene, so that the stability of the modified graphene lubricant reaches 12 to 18 months, which extends the shelf life of the galvanized metal forming lubricant.

[0021] Secondly, the present application also discloses a method for preparing a galvanized metal forming lubricant, comprising adding a modified graphene lubricant, an oiliness agent, a rust inhibitor, a corrosion inhibitor additive, an antioxidant and a base oil into a container and stirring the mixture evenly at a temperature of 55 to 60°C to obtain the galvanized metal forming lubricant.

[0022] In summary, this application has the following beneficial effects:

[0023] 1. This technical solution involves reacting graphene oxide with enamine in a specific ratio at a specific temperature for a specific time. During this process, the graphene oxide particles absorb enamine chains of a certain length due to electrostatic adsorption, resulting in a stable dispersion product. The product is filtered and washed with anhydrous ethanol. The product is then dissolved in a solvent composed of ether and polyalphaolefin to produce a modified graphene lubricant, thereby improving the graphene's poor solubility in organic solvents. This modified graphene lubricant is then combined with an oiliness agent, a rust inhibitor, a corrosion inhibitor, an antioxidant, and a base oil to form a galvanized metal forming lubricant, which improves the lubricant's stability and thus its shelf life.

[0024] 2. In the present invention, during the electrostatic adsorption process of graphene oxide and enamine, an electric current is passed through the reaction solution, and under the action of 3-aminopropyltriethoxysilane, the stability of the electrostatic adsorption of the enamine molecular chain on the graphene oxide particles can be further improved, thereby further improving the stability of the modified graphene, making the modified graphene lubricant more stable and the shelf life of the galvanized metal forming lubricant longer.

[0025] 3. The lubricating oil of the present invention is used in high-strength metal forming processing procedures, has good lubricity and good forming properties; the product does not contain sulfur, thus avoiding damage to the zinc coating, and the corrosion inhibitor additives used have a good corrosion inhibition effect on both copper and zinc. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1

[0028] This embodiment is a method for preparing a galvanized metal forming lubricant, comprising the following steps:

[0029] S1. Preparation of modified graphene lubricant, comprising the following steps:

[0030] S101, dissolving 1 kg of graphene oxide with a particle size of 10 to 50 μm in 1000 L of deionized water, and ultrasonicating for 20 min to form a uniform dispersion;

[0031] S102, adding an acidic substance to the dispersion. In this embodiment, the acidic substance is hydrochloric acid, and adjusting the pH of the dispersion to about 2;

[0032] S103, stirring at 170 ° C and slowly adding 3 kg of enamine, after the enamine is added, adding 1 kg of 3-aminopropyltriethoxysilane, and stirring evenly; then placing a cathode plate and an anode plate in the reaction solution, and during the reaction, intermittently passing 18 V, 1 A alternating current through the cathode plate and the anode plate during the reaction, the intermittent frequency is 15 minutes on and 15 minutes off; after reacting for 18 hours, a paste product is obtained;

[0033] S104, filtering the paste product and washing it with anhydrous ethanol to obtain modified graphene;

[0034] S105, dissolving the modified graphene in 150 kg of a solvent ether and a poly-alpha olefin solvent in a mass ratio of 1:1 to obtain a modified graphene lubricant.

[0035] S2. Preparation of corrosion inhibitor additive (N,N-bis(5-methylbenzotriazolemethylene)hexadecylamine metal deactivator):

[0036] 5-Methylbenzotriazole, hexadecylamine, and formaldehyde are added to a reaction solvent, stirred, and heated to 60°C to dissolve. Once completely dissolved, the temperature is raised to 80°C for reaction. After the reaction is complete, the product is extracted and separated using D60 gasoline solvent to obtain a corrosion inhibitor. In this embodiment, the mass ratio of 5-methylbenzotriazole, hexadecylamine, and formaldehyde is 1:2:3, i.e., 1 kg of 5-methylbenzotriazole, 2 kg of hexadecylamine, and 3 kg of formaldehyde. The reaction solvent is a 70-80% ethanol solution, and the mass of the reaction solvent is three times the mass of 5-methylbenzotriazole, i.e., 3 kg. The solvent ether is dibutyl ether, and the polyalphaolefin is polydecene.

[0037] S3. Add the modified graphene lubricant, oiliness agent, rust inhibitor prepared in step S1, the corrosion inhibitor, antioxidant and base oil prepared in step S2 into a container, and stir them evenly at a temperature of 55° C. to obtain the galvanized metal forming lubricant; wherein the mass percentages of the above raw materials are: 10% modified graphene lubricant, 8% oiliness agent, 5% rust inhibitor, 0.1% corrosion inhibitor, 0.1% antioxidant, and the balance is base oil and unavoidable impurities.

[0038] In this embodiment, the enamine is hexadeceneamine; the oiliness agent is rapeseed oil; the rust inhibitor is barium dinonylnaphthalenesulfonate; the antioxidant is thiocarbamate; and the base oil is white oil.

[0039] Example 2

[0040] This embodiment is a second method for preparing a galvanized metal forming lubricant, comprising the following steps:

[0041] S1. Preparation of modified graphene lubricant, comprising the following steps:

[0042] S101, dissolving 1 kg of graphene oxide with a particle size of 10 to 50 μm in 1000 L of deionized water, and ultrasonicating for 25 min to form a uniform dispersion;

[0043] S102, adding an acidic substance to the dispersion. In this embodiment, the acidic substance is hydrochloric acid, and adjusting the pH of the dispersion to about 2.5;

[0044] S103, stirring at 180 ° C and slowly adding 4 kg of enamine, after the enamine is added, adding 2 kg of 3-aminopropyltriethoxysilane, and stirring evenly; then placing a cathode plate and an anode plate in the reaction solution, and during the reaction, intermittently passing 27 V, 1.5 A of alternating current through the cathode plate and the anode plate during the reaction, the intermittent frequency is 20 minutes on and 20 minutes off; after reacting for 24 hours, a paste product is obtained;

[0045] S104, filtering the paste product and washing it with anhydrous ethanol to obtain modified graphene;

[0046] S105, dissolving the modified graphene in 200 kg of a solvent ether and a poly-alpha-olefin solvent in a mass ratio of 1:1 to obtain a modified graphene lubricant.

[0047] S2. Preparation of corrosion inhibitor additive (N,N-bis(5-methylbenzotriazolemethylene)hexadecylamine metal deactivator):

[0048] 5-Methylbenzotriazole, hexadecylamine and formaldehyde are added to a reaction solvent, stirred and heated to 65°C for dissolution; after complete dissolution, the temperature is raised to 85°C for reaction; after the reaction is completed, the product is extracted and separated with D60 solvent gasoline to obtain a corrosion inhibitor additive.

[0049] In this embodiment, the mass ratio of 5-methylbenzotriazole, hexadecylamine, and formaldehyde is 1.5:2.5:3.5, i.e., 1.5 kg of 5-methylbenzotriazole, 2.5 kg of hexadecylamine, and 3.5 kg of formaldehyde. The reaction solvent is N,N-dimethylformamide, and the mass of the reaction solvent is 4 times the mass of 5-methylbenzotriazole, i.e., 6 kg. The solvent ether is a mixture of equal volumes of ethylene glycol dimethyl ether, ethylene glycol dipropyl ether, and ethylene glycol dibutyl ether. The polyalphaolefin is polydodecene.

[0050] S3. Add the modified graphene lubricant, oiliness agent, rust inhibitor prepared in step S1, the corrosion inhibitor, antioxidant and base oil prepared in step S2 into a container, and stir them evenly at a temperature of 57.5° C. to obtain the galvanized metal forming lubricant; wherein the mass percentages of the above raw materials are: 12.5% modified graphene lubricant, 10% oiliness agent, 7.5% rust inhibitor, 0.3% corrosion inhibitor, 0.2% antioxidant, and the balance is base oil and unavoidable impurities.

[0051] In this embodiment, the enamine is an equal volume combination of octadecylamine, eicosylamine, 3-methylhexadecylamine, and 1-methyloctadecylamine; the oiliness agent is an equal volume combination of hydrogenated lard, trimethylolpropane ester, dipentaerythritol ester, isooctanoic acid diester, pentaerythritol ester, and tetrakis(3-mercaptobutyric acid)pentaerythritol ester; the rust inhibitor is an equal volume combination of barium petroleum sulfonate and calcium dinonylnaphthalene sulfonate; the antioxidant is zinc thiocarbamate; and the base oil is engine oil.

[0052] Example 3

[0053] This embodiment is a third method for preparing a galvanized metal forming lubricant, comprising the following steps:

[0054] S1. Preparation of modified graphene lubricant, comprising the following steps:

[0055] S101, dissolving 1 kg of graphene oxide with a particle size of 10 to 50 μm in 1000 L of deionized water, and ultrasonicating for 30 min to form a uniform dispersion;

[0056] S102, adding an acidic substance to the dispersion. In this embodiment, the acidic substance is dilute sulfuric acid, and adjusting the pH of the dispersion to 3;

[0057] S103, stirring at 190 ° C and slowly adding 5 kg of enamine, after the enamine is added, adding 3 kg of 3-aminopropyltriethoxysilane, stirring evenly; then placing a cathode plate and an anode plate in the reaction solution, and during the reaction, intermittently passing 36 V, 2 A AC power to the cathode plate and the anode plate, the intermittent frequency is 25 minutes on and 25 minutes off; after reacting for 30 hours, a paste product is obtained;

[0058] S104, filtering the paste product and washing it with anhydrous ethanol to obtain modified graphene;

[0059] S105, dissolving the modified graphene in 250 kg of a solvent ether and a poly-alpha olefin solvent in a mass ratio of 1:1 to obtain a modified graphene lubricant.

[0060] S2. Preparation of corrosion inhibitor additive (N,N-bis(5-methylbenzotriazolemethylene)hexadecylamine metal deactivator):

[0061] 5-Methylbenzotriazole, hexadecylamine and formaldehyde are added to a reaction solvent, stirred and heated to 70°C for dissolution; after complete dissolution, the temperature is raised to 90°C for reaction; after the reaction is completed, the product is extracted and separated with D60 solvent gasoline to obtain a corrosion inhibitor additive.

[0062] In this embodiment, the mass ratio of 5-methylbenzotriazole, hexadecylamine, and formaldehyde is 2:3:4, i.e., 2 kg of 5-methylbenzotriazole, 3 kg of hexadecylamine, and 4 kg of formaldehyde; the reaction solvent is toluene, and the mass of the reaction solvent is 10 kg, which is 5 times the mass of 5-methylbenzotriazole. The solvent ether is a mixture of equal volumes of dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, and ethylene glycol dibutyl ether; and the polyalphaolefin is a mixture of equal volumes of polydecene and polydodecene.

[0063] S3. Add the modified graphene lubricant, oiliness agent, rust inhibitor prepared in step S1, the corrosion inhibitor, antioxidant and base oil prepared in step S2 into a container, and stir them evenly at a temperature of 60°C to obtain the galvanized metal forming lubricant; wherein the mass percentages of the above raw materials are: 15% modified graphene lubricant, 12% oiliness agent, 10% rust inhibitor, 0.5% corrosion inhibitor, 0.3% antioxidant, and the balance is base oil and inevitable impurities.

[0064] In this embodiment, the enamine is a mixture of equal volumes of hexadecenamine, octadecenamine, eicoseneamine, 3-methylhexadecenamine, and 1-methyloctadecenamine; the oiliness agent is a mixture of equal volumes of low-erucic acid rapeseed oil, hydrogenated lard, trimethylolpropane ester, dipentaerythritol ester, isooctanoic acid diester, pentaerythritol ester, and tetrakis(3-mercaptobutyric acid)pentaerythritol ester; the rust inhibitor is a mixture of equal volumes of barium dinonylnaphthalenesulfonate, barium petroleum sulfonate, and calcium dinonylnaphthalenesulfonate; the antioxidant is a mixture of equal volumes of thiocarbamate and zinc thiocarbamate; and the base oil is a mixture of equal volumes of white oil and engine oil.

[0065] Example 4

[0066] Compared with Example 2, the only difference between this embodiment is that the modified graphene lubricant prepared in step S1 is not added to the galvanized metal forming lubricant in this embodiment, and 10-50 micron graphene oxide is directly used.

[0067] Example 5

[0068] Compared with Example 2, the only difference between this embodiment is that in step S103 of adding the modified graphene lubricant to the galvanized metal forming lubricant in this embodiment, no power treatment is performed, that is, 5 kg of enamine is slowly added dropwise while stirring at 190°C. After the enamine is added, the reaction is carried out for 30 hours to obtain a paste product.

[0069] Example 6

[0070] The only difference between this embodiment and embodiment 2 is that the corrosion inhibitor added to the galvanized metal forming lubricant in this embodiment is a currently commonly used sulfonate corrosion inhibitor.

[0071] The following indicators are compared for Examples 1 to 6, as well as an existing sulfur-containing lubricating oil as a comparative example. Appearance is determined by visual inspection, kinematic viscosity is determined by the method of GB / T 265, corrosion test is determined by the method of GB / T 5096, wear spot diameter is determined by the method of GB / T 3142, and precipitation is the percentage of graphene oxide per unit volume of lubricating oil after drying, as shown below:

[0072] Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example Appearance Dark yellow oil Dark yellow oil Dark yellow oil Dark yellow oil Dark yellow oil Dark yellow oil Brown oil Kinematic viscosity (40℃, mm2 / s) 121 123 123 121 124 125 116 Corrosion test (100°C, 3 h) Copper Grade A Zinc Grade A Copper Grade A Zinc Grade A Copper Grade A Zinc Grade A Copper Grade A Zinc Grade A Copper Grade A Zinc Grade A Copper Grade A Zinc Grade A Copper Grade A Zinc Grade A Wear spot diameter (392N, 1200 rpm, 75°C, 1 hour) 0.351mm 0.349mm 0.350mm 0.376mm 0.355mm 0.357mm 0.432mm 60-day sedimentation volume 0 0 0 0.40% 0 0 / 180-day sedimentation volume 0.11% 0.10% 0.12% 5.7% 0.20% 0.10% / 360-day sedimentation volume 0.33% 0.35% 0.40% 12.5% 1.40% 0.41% / 720-day sedimentation 0.83% 0.81% 0.84% 25.20% 4.30% 0.88% /

[0073] The lubricating oil product produced by the present invention exhibits superior lubricity compared to traditional sulfur-containing products. Because it does not use sulfur-containing raw materials, the reaction between the sulfur agent and zinc during processing does not damage the zinc coating, thereby preventing damage to the material coating. Furthermore, the specially formulated metal deactivating corrosion inhibitor of the present invention requires minimal addition and exhibits excellent sustained-release properties for zinc and copper. Furthermore, the above results demonstrate that the lubricating oil produced by the method of the present invention exhibits excellent stability and a longer shelf life.

[0074] The above embodiments are intended only to illustrate the technical solutions of the present invention and are not intended to limit the scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art will appreciate that the technical solutions of the present invention may be modified or replaced with equivalents without departing from the spirit and scope of the technical solutions of the present invention, and such modifications or equivalents shall be encompassed by the claims of the present invention. Any techniques, shapes, and structures not described in detail herein are well known.

Claims

1. A galvanized metal forming lubricant, characterized in that: The invention comprises the following raw materials by mass percentage: 10-15% modified graphene lubricant, 8-12% oiliness agent, 5-10% rust inhibitor, 0.1-0.5% corrosion inhibitor, 0.1-0.3% antioxidant, and the balance is base oil and inevitable impurities; the modified graphene lubricant is obtained by enamine-modified graphene oxide.

2. A galvanized metal forming lubricant according to claim 1, characterized in that: The enamine is any one of hexadecenamine, octadecenamine, eicoseneamine, 3-methylhexadecenamine, and 1-methyloctadecenamine, or a combination thereof.

3. A galvanized metal forming lubricant according to claim 1, characterized in that: The oiliness agent is any one or a combination of low-erucic acid rapeseed oil, hydrogenated lard, trimethylolpropane ester, dipentaerythritol ester, isooctanoic acid diester, pentaerythritol ester, and tetrakis(3-mercaptobutyric acid)pentaerythritol ester; the rust inhibitor is any one or a combination of barium dinonylnaphthalene sulfonate, barium petroleum sulfonate, and calcium dinonylnaphthalene sulfonate.

4. A galvanized metal forming lubricant according to claim 1, characterized in that: The antioxidant is any one of thiocarbamate and zinc thiocarbamate or a combination of the two; the base oil is any one of white oil and engine oil or a combination of the two.

5. A galvanized metal forming lubricant according to any one of claims 1 to 4, characterized in that: The corrosion inhibitor additive is an N,N-bis(5-methylbenzotriazole methylene) hexadecylamine metal deactivator. The preparation method of the corrosion inhibitor additive comprises: adding 5-methylbenzotriazole, hexadecylamine and formaldehyde into a reaction solvent, stirring and heating to 60-70°C to dissolve; after complete dissolution, heating to 80-90°C to react; after the reaction is completed, extracting and separating the product with D60 solvent gasoline to obtain the corrosion inhibitor additive.

6. A galvanized metal forming lubricant according to claim 5, characterized in that: The mass ratio of the 5-methylbenzotriazole, hexadecylamine, and formaldehyde is (1-2): (2-3): (3-4); the reaction solvent is one of a 70-80% ethanol solution, N,N-dimethylformamide, and toluene, and the mass of the reaction solvent is 3-5 times the mass of 5-methylbenzotriazole.

7. A galvanized metal forming lubricant according to any one of claims 1 to 4, characterized in that: The preparation method of the modified graphene lubricant comprises: S1. Dissolve 1 part of graphene oxide in deionized water by mass and ultrasonicate for 20-30 min to form a uniform dispersion. S2. Add an acidic substance to the dispersion to adjust the pH of the dispersion to 2-3; S3, adding 3-5 parts of enamine dropwise with stirring at 170-190° C., and reacting for 18-30 hours to obtain a paste product; S4, filtering the paste product and washing it with anhydrous ethanol to obtain modified graphene; S5. Dissolving the modified graphene in 150-250 parts of a solvent ether and a poly-alpha-olefin solvent to obtain a modified graphene lubricant.

8. A galvanized metal forming lubricant according to claim 7, characterized in that: The solvent ether is one of dibutyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dipropyl ether, and ethylene glycol dibutyl ether, or a mixture of several of them; the polyalphaolefin is any one of polydecene and polydodecene.

9. The galvanized metal forming lubricant according to claim 7, characterized in that: In step S3, after the enamine is added dropwise, 1 to 3 parts of 3-aminopropyltriethoxysilane is added and stirred evenly; then, a cathode plate and an anode plate are placed in the reaction solution. During the reaction, an alternating current of 18 to 36 V and a current of 1 to 2 A is intermittently supplied to the cathode plate and the anode plate, and the intermittent frequency is 15 to 25 minutes on and 15 to 25 minutes off.

10. A method for preparing a galvanized metal forming lubricant, characterized in that: The modified graphene lubricant, oiliness agent, rust inhibitor, corrosion inhibitor, antioxidant and base oil according to any one of claims 1 to 9 are added into a container and stirred evenly at a temperature of 55 to 60° C. to obtain the galvanized metal forming lubricant.