An electric vehicle axle gear oil and its production process

Abstract

The present invention relates to the technical field of lubricating oils, and particularly to an axle gear oil for electric vehicles and its production process; the gear oil is composed of the following raw materials in parts by weight: 90-110 parts of base oil, 0.5-1.2 parts of N, N-dibutylaminotolyltriazole, 9-12 parts of viscosity modifier, 10-15 parts of polyol ester, 1-3 parts of pour point depressant, 1-2 parts of compound antioxidant, 1.5-2.5 parts of demulsifier, 0.8-1.5 parts of rust inhibitor, 3-6 parts of extreme pressure and anti-wear agent, 0.2-0.6 parts of defoamer and 5-8 parts of functional additive; the gear oil produced by the present invention not only has excellent high-temperature resistance and wear-resistant and friction-reducing properties, but also has good antioxidant properties, reduces the wear degree of axle gears to a certain extent, extends the service life of the gear oil and also extends the service life of axle gears, effectively ensuring the grade and quality of the gear oil.

Description

Technical Field

[0001] The invention relates to the technical field of lubricating oil, in particular to an electric vehicle axle gear oil and a production process thereof. Background Art

[0002] Gear oil is a kind of lubricant made of petroleum lubricant base oil or synthetic lubricant, with extreme pressure anti-wear agent and oiliness agent added. It mainly plays the role of lubricating gears and bearings, preventing wear and corrosion, and helping gears to dissipate heat. It is used in various gear transmission devices to extend their service life and improve the transmission power efficiency.

[0003] Due to the vigorous development of new energy vehicles, electric motors have gradually replaced traditional fuel engines, so the demand for lubricating oil has been greatly reduced. However, due to the higher sealing requirements of the front and rear axles of new energy vehicles, the requirements for gear oil have also gradually increased. It requires not only that the gear oil has excellent wear resistance, but also that it has excellent antioxidant properties. In the patent document with application number "CN201811274622.8", a special gear oil for ultra-low temperature subway and its preparation method are disclosed, which belong to the field of motor oil. The gear oil contains the following components in mass percentage: base oil 70-80%, alkyl naphthalene 5-15%, polyol ester 10-20%, pour point depressant 0.3-2%, antioxidant 0.5-1.5%, and compounding agent 1-10%, wherein the base oil is composed of poly-α-olefin base oil and ester base oil, and the poly-α-olefin base oil accounts for 60-75% of the total base oil, and the ester base oil includes dioctyl sebacate and polymethacrylate, which account for 20-30% and 5-15% of the total base oil, respectively.

[0004] Although the gear oil prepared by the above patent document has excellent low temperature resistance and can meet the use requirements of subway vehicles in cold regions such as Northwest and Northeast my country, its wear resistance and friction reduction performance is relatively insufficient, which will aggravate the wear of the axle gear and shorten its service life. Furthermore, its antioxidant performance is also relatively insufficient, which will accelerate the oxidation and deterioration of the gear oil, produce sludge and sediment, affect the lubrication effect and shorten the service life of the axle gear. Therefore, the present invention provides an electric vehicle axle gear oil and a production process thereof to solve the above-mentioned technical problems. Summary of the invention

[0005] The purpose of the present invention is to provide an electric vehicle axle gear oil and a production process thereof. The gear oil produced not only has excellent high temperature resistance and wear resistance and friction reduction performance, but also has good antioxidant performance, which reduces the wear degree of the axle gear to a certain extent, prolongs the service life of the gear oil and also prolongs the service life of the axle gear, effectively ensuring the grade and quality of the gear oil.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] An axle gear oil for electric vehicles, the gear oil is composed of the following raw materials in parts by weight: 90-110 parts of base oil, 0.5-1.2 parts of N, N-dibutylaminotoluene triazole, 9-12 parts of viscosity modifier, 10-15 parts of polyol ester, 1-3 parts of pour point depressant, 1-2 parts of compound antioxidant, 1.5-2.5 parts of demulsifier, 0.8-1.5 parts of rust inhibitor, 3-6 parts of extreme pressure and anti-wear agent, 0.2-0.6 parts of defoamer and 5-8 parts of functional additive;

[0008] Among them, the pour point depressant is compounded by alkyl naphthalene and acrylic polymer in a mass ratio of 1:1-2; the compound antioxidant is compounded by phenolic antioxidant and amine antioxidant in a mass ratio of 1:1-1.5;

[0009] The acrylic polymer is selected from polymethyl methacrylate 1-368 or polymethyl methacrylate LZ 7749B;

[0010] The phenolic antioxidant is selected from antioxidant BHT or antioxidant 1010;

[0011] The amine antioxidant is selected from 4,4'-dioctyldiphenylamine or butyloctylated diphenylamine;

[0012] The demulsifier is demulsifier D114 or demulsifier T1001;

[0013] The rust inhibitor is benzotriazole or barium dinonylnaphthalene sulfonate;

[0014] The extreme pressure and anti-wear agent is any one of tricresyl phosphate, phenyl thionophosphate, and sulfurized isobutene;

[0015] The defoamer is dimethyl silicone oil or Degussa TEGO Foamex 830 defoamer;

[0016] Furthermore, the preparation method of the functional additive includes the following steps: uniformly disperse the pretreated carrier substrate in toluene according to a solid-liquid ratio of 10-30 g / L, add a silane coupling agent KH-580 with a mass 0.2-0.4 times that of the pretreated carrier substrate, mix and stir evenly, and then reflux and stir for reaction for 4-6 h; after the reaction is completed, cool the temperature of the product components to 50-65 °C, and then add a modifier with a mass 0.6-1.2 times that of the pretreated carrier substrate, an antioxidant GM with a mass 0.5-0.8 times that of the pretreated carrier substrate, and dibutyltin dilaurate with a mass 0.08-0.12 times that of the pretreated carrier substrate, mix and stir evenly, and then keep warm and stir for reaction at a temperature of 50-65 °C for 5-8 h; after the reaction is completed, filter and vacuum dry the product components in sequence, and the obtained product is the functional additive.

[0017] Further, the preparation method of the modifier is as follows: 5-isocyanatoisophthaloyl chloride is uniformly dispersed in acetone with a mass 3 to 5 times that of it, and then 2,6-di-tert-butyl-4-hydroxymethylphenol with a molar amount 2 to 3 times that of 5-isocyanatoisophthaloyl chloride is added under an ice-water bath environment. After mixing and stirring evenly, the mixture is stirred and reacted at a temperature of 20 to 30 °C for 5 to 8 h; the modifier is obtained after the reaction is completed.

[0018] Further, the preparation method of the pretreated carrier substrate is as follows: The carrier substrate is soaked in a hydrofluoric acid solution with a mass 10 to 15 times that of it and a concentration of 30 wt% for 20 to 25 h, and then the carrier substrate is filtered out and washed 3 to 5 times with deionized water; after washing, it is soaked in an aqueous hydrogen peroxide solution with the same mass and concentration as the hydrofluoric acid solution for 40 to 60 min, and then obtained as the pretreated carrier substrate after filtration and natural drying.

[0019] Further, the preparation method of the carrier substrate includes the following steps:

[0020] Step 1: The nano-zirconia microspheres (purchased from Beijing Beike New Materials Technology Co., Ltd., with an average particle size of 20 nm and a specific surface area of 30 to 50 m 2 / g) are uniformly dispersed in ethanol according to a solid-liquid ratio of 20 to 50 g / L, and then 3-aminopropyltrimethoxysilane with a mass 0.1 to 0.2 times that of the nano-zirconia microspheres is added. After stirring evenly, the mixture is refluxed and reacted for 3 to 5 h; after the reaction is completed, the reaction product is centrifuged, washed with water and dried in sequence; the obtained modified nano-zirconia microspheres are stored and reserved for use;

[0021] Step 2: The modified nano-zirconia microspheres are put into DMF according to a solid-liquid ratio of 50 to 80 g / L, and then carboxylated graphene with a mass 2 to 3 times that of the modified nano-zirconia, dicyclohexylcarbodiimide with a mass 5 to 10 times that of the modified nano-zirconia, and N,N-dimethyl-4-pyridinamine with a mass 1.0 to 1.5 times that of the modified nano-zirconia are added. After mixing and stirring evenly, the mixture is kept warm and stirred at a temperature of 30 to 40 °C for 30 to 50 h; after the reaction is completed, the components of the product are filtered, and the obtained filter cake is washed 2 to 3 times with distilled water and ethanol respectively, and then after drying, the obtained solid powder is mixed and stirred evenly with silicon powder with a mass 3 to 5 times that of it, and finally high-temperature treatment is carried out in an argon atmosphere, and the obtained is the carrier substrate.

[0022] Further, the high-temperature treatment process is as follows: First, heat treatment is carried out at a temperature of 800 to 1200 °C for 2 to 3 h, and then heat treatment is carried out at a temperature of 1500 to 1800 °C for 2 to 4 h; among them, when adjusting the temperature, the heating rate is set to 5 to 10 °C / min.

[0023] Furthermore, the base oil is prepared by mixing high-viscosity synthetic base oil, poly-α-olefin base oil and polyester base oil in a ratio of 8 to 10: 1: 1 to 2;

[0024] Among them, the high-viscosity synthetic base oil is Indonesian PX20 or Shell X420; the polyalphaolefin base oil is Mobil PAO4 or Mobil PAO6; the polyester base oil is Italian Ite Polyester KL115 or Italian Ite Polyester KL135.

[0025] Furthermore, the viscosity modifier is selected from any one of Afton HiTEC 5777, Afton HiTEC 3339, and Afton HiTEC 355.

[0026] Furthermore, the polyol ester is any one of TM108, TM118 and TM143.

[0027] A production process of electric vehicle axle gear oil comprises the following steps: weighing various raw materials according to the formula amount, then transferring the base oil, functional additives and defoaming agent into a blending kettle, raising the kettle temperature to 60-70°C and adding the remaining raw materials into the blending kettle while stirring at this temperature, maintaining the kettle temperature at 60-70°C, and continuing stirring at a rate of 600-800 r / min for 1-2 hours, and finally obtaining the electric vehicle axle gear oil.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] The present invention firstly performs modification treatment on nano zirconium oxide microspheres by 3-aminopropyltrimethoxysilane, so that the two are connected by chemical bonds, and the modified nano zirconium oxide microspheres are prepared. The modified nano zirconium oxide microspheres are put into DMF and carboxylated graphene, dicyclohexylcarbodiimide and N, N-dimethyl-4-pyridylamine are added respectively, and a chemical reaction occurs under the action of N, N-dimethyl-4-pyridylamine, and the obtained solid powder is mixed with silicon powder, and high-temperature treatment is performed under the protection of rare gas, and finally a layer of silicon carbide coating film is formed on the surface of the modified nano zirconium oxide. Since nano zirconium oxide itself has good wear resistance, the "ball" structure of the nano zirconium oxide microspheres makes its wear resistance better. Moreover, the existence of the silicon carbide coating film further improves the wear resistance and friction reduction performance of the carrier substrate.

[0030] The obtained carrier substrate is first soaked in a hydrofluoric acid solution and then in an aqueous hydrogen peroxide solution, so that the surface of the finally prepared pretreated carrier substrate is rich in hydroxyl groups, laying the foundation for subsequent chemical reactions. The pretreated carrier substrate is dispersed in toluene, and the silane coupling agent KH-580 is added to modify it. Then, antioxidant GM is added thereto. Under the mediating effect of the silane coupling agent KH-580, antioxidant GM is successfully "grafted" onto the surface of the pretreated carrier substrate. The modifier reacts with the active groups on the surface of the pretreated carrier substrate under the action of dibutyltin dilaurate and is bonded, so that the modifier with excellent antioxidant performance is "grafted" onto the surface of the pretreated carrier substrate. The prepared functional additive has an obvious core-shell structure, the "core" layer is the pretreated carrier substrate, and the "shell" layer is a three-dimensional antioxidant envelope layer formed by the interlacing of the modifier and antioxidant GM. The presence of the three-dimensional envelope layer makes the functional additive have excellent antioxidant performance, while the nano-zirconia microspheres and the silicon carbide coating film layer on their surfaces make the functional additive have excellent wear and friction reduction performance.

[0031] In summary, the functional additive prepared by the present invention is used as a raw material for the axle gear oil of electric vehicles, making the produced gear oil not only have excellent high-temperature resistance, wear and friction reduction performance, but also have good antioxidant performance. To a certain extent, it reduces the wear degree of the axle gears, extends the service life of the gear oil and also extends the service life of the axle gears, effectively ensuring the grade and quality of the gear oil. Specific Embodiments

[0032] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0033] Example 1

[0034] An axle gear oil for electric vehicles, the gear oil is composed of the following raw materials in parts by weight: 90 parts of base oil, 0.5 part of N,N-dibutylaminotoluene triazole, 9 parts of Afton HiTEC 5777 viscosity modifier, 10 parts of polyol ester TM108, 1 part of pour point depressant, 1 part of compound antioxidant, 1.5 parts of demulsifier D114, 0.8 part of benzotriazole, 3 parts of tricresyl phosphate, 0.2 part of dimethyl silicone oil and 5 parts of functional additive;

[0035] Among them, the pour point depressant is prepared by compounding alkyl naphthalene and polymethacrylate 1-368 in an equal mass ratio; the antioxidant is prepared by compounding antioxidant BHT and 4,4'-dioctyldiphenylamine in an equal mass ratio;

[0036] The base oil is prepared by mixing a high-viscosity synthetic base oil, a polyalphaolefin base oil, and a polyester base oil in a ratio of 8:1:1; among them, the high-viscosity synthetic base oil is PX20 from Indonesia; the polyalphaolefin base oil is Mobil PAO4; and the polyester base oil is Italian Italec KL115.

[0037] The preparation method of the functional additive includes the following steps: uniformly disperse the pretreated carrier substrate in toluene according to a solid-liquid ratio of 10 g / L, add a silane coupling agent KH-580 with a mass 0.2 times that of the pretreated carrier substrate, mix and stir evenly, and then reflux and stir for reaction for 4 h; after the reaction is completed, lower the temperature of the product components to 50 °C, then add a modifier with a mass 0.6 times that of the pretreated carrier substrate, an antioxidant GM with a mass 0.5 times that of the pretreated carrier substrate, and dibutyltin dilaurate with a mass 0.08 times that of the pretreated carrier substrate, mix and stir evenly, and then keep the temperature at 50 °C and stir for reaction for 5 h; after the reaction is completed, filter and vacuum-dry the product components in sequence, and what is obtained is the functional additive.

[0038] The preparation method of the modifier is as follows: uniformly disperse 5-isocyanatoisophthaloyl chloride in acetone with a mass 3 times that of it, then add 2,6-di-tert-butyl-4-hydroxymethylphenol with a molar amount 2 times that of 5-isocyanatoisophthaloyl chloride in an ice-water bath environment, mix and stir evenly, and then stir for reaction at a temperature of 20 °C for 5 h; after the reaction is completed, the modifier is obtained.

[0039] The preparation method of the pretreated carrier substrate is as follows: soak the carrier substrate in a hydrofluoric acid solution with a mass 10 times that of it and a concentration of 30 wt% for 20 h, then filter out the carrier substrate and wash it 3 times with deionized water; after washing, soak it in an aqueous hydrogen peroxide solution with the same mass and concentration as the hydrofluoric acid solution for 40 min, and then filter and air-dry it to obtain the pretreated carrier substrate.

[0040] The preparation method of the carrier substrate includes the following steps:

[0041] Step 1: Uniformly disperse nano-zirconia microspheres in ethanol according to a solid-liquid ratio of 20 g / L, then add 3-aminopropyltrimethoxysilane with a mass 0.1 times that of the nano-zirconia microspheres, stir evenly, and then reflux for reaction for 3 h; after the reaction is completed, perform centrifugal separation, water washing, and drying treatment on the reaction product in sequence; the obtained modified nano-zirconia microspheres are stored and reserved for use;

[0042] Step 2: Put the modified nano-zirconia microspheres into DMF according to the solid-liquid ratio of 50 g / L, then add carboxylated graphene which is 2 times the mass of the modified nano-zirconia, dicyclohexylcarbodiimide which is 5 times the mass, and N,N-dimethyl-4-pyridinamine which is 1.0 times the mass. After mixing and stirring evenly, keep the temperature at 30 °C and stir and react for 30 h while maintaining the temperature. After the reaction is completed, filter the components of the product. Wash the obtained filter cake twice with distilled water and ethanol respectively, and then after drying treatment, mix and stir evenly the obtained solid powder with silicon powder which is 3 times its mass. Finally, conduct high-temperature treatment in an argon atmosphere, and the obtained product is the carrier substrate. Among them, the high-temperature treatment process is as follows: First, conduct heat treatment at 800 °C for 3 h, and then conduct heat treatment at 1500 °C for 4 h. Among them, when adjusting the temperature, the heating rate is set at 5 °C / min.

[0043] A production process of an electric vehicle axle gear oil includes the following steps: Weigh each raw material according to the formula amount, then transfer the base oil, functional additives and defoamer into a blending kettle, raise the temperature of the kettle to 60 °C, and while stirring at this temperature, add the remaining raw materials into it. Keep the temperature of the kettle at 60 °C and continue to stir at a rate of 600 r / min for 1 h. The finally obtained product is the electric vehicle axle gear oil.

[0044] Example 2

[0045] The production process of an electric vehicle axle gear oil provided in this example is basically the same as that in Example 1, except that: the specific composition of the raw materials used and the preparation method of the functional additives are not exactly the same, and the specific composition of the raw materials used and the preparation method of the functional additives in this example are as follows:

[0046] An electric vehicle axle gear oil, and the gear oil is composed of the following raw materials in parts by weight: 100 parts of base oil, 1.0 part of N,N-dibutylaminomethylbenzene triazole, 10 parts of Afton HiTEC3339 viscosity modifier, 12 parts of polyol ester TM 118, 2 parts of pour point depressant, 1.5 parts of compound antioxidant, 2.0 parts of demulsifier T1001, 1.2 parts of barium dinonylnaphthalene sulfonate, 5 parts of phenyl thionophosphate, 0.4 part of Degussa TEGO Foamex 830 defoamer and 6 parts of functional additives;

[0047] The preparation method of the functional additive includes the following steps: The pretreated carrier substrate is uniformly dispersed in toluene at a solid-liquid ratio of 20 g / L, and silane coupling agent KH-580 with a mass 0.3 times that of the pretreated carrier substrate is added. After mixing and stirring evenly, reflux stirring reaction is carried out for 5 h; After the reaction is completed, the temperature of the product components is reduced to 60 °C, and then a modifier with a mass 0.8 times that of the pretreated carrier substrate, antioxidant GM with a mass 0.6 times that of the pretreated carrier substrate, and dibutyltin dilaurate with a mass 0.1 times that of the pretreated carrier substrate are added. After mixing and stirring evenly, heat preservation stirring reaction is carried out at a temperature of 60 °C for 6 h; After the reaction is completed, the product components are filtered and vacuum dried in sequence, and the obtained product is the functional additive.

[0048] The preparation method of the modifier is as follows: 5-isocyanatoisophthaloyl chloride is uniformly dispersed in acetone with a mass 4 times that of it, and then 2,6-di-tert-butyl-4-hydroxymethylphenol with a molar amount 3 times that of 5-isocyanatoisophthaloyl chloride is added under the environment of ice-water bath. After mixing and stirring evenly, stirring reaction is carried out at a temperature of 25 °C for 6 h; After the reaction is completed, the modifier is obtained.

[0049] The preparation method of the pretreated carrier substrate is as follows: The carrier substrate is soaked in a hydrofluoric acid solution with a mass 10 times that of it and a concentration of 30 wt% for 20 h, and then the carrier substrate is filtered out and washed 4 times with deionized water; After washing, it is soaked in an aqueous hydrogen peroxide solution with the same mass and concentration as the hydrofluoric acid solution for 50 min, and then filtered and naturally dried to obtain the pretreated carrier substrate.

[0050] The preparation method of the carrier substrate includes the following steps:

[0051] Step 1: Uniformly disperse nano-zirconia microspheres in ethanol at a solid-liquid ratio of 30 g / L, and then add 3-aminopropyltrimethoxysilane with a mass 0.15 times that of the nano-zirconia microspheres. After stirring evenly, reflux reaction is carried out for 4 h; After the reaction is completed, the reaction product is centrifuged, washed with water and dried in sequence; The obtained modified nano-zirconia microspheres are stored and reserved for use;

[0052] Step 2: Put the modified nano-zirconia microspheres into DMF at a solid-liquid ratio of 60 g / L, and then add carboxylated graphene with a mass 3 times that of the modified nano-zirconia, dicyclohexylcarbodiimide with a mass 8 times that of the modified nano-zirconia, and N,N-dimethyl-4-pyridinamine with a mass 1.2 times that of the modified nano-zirconia. After mixing and stirring evenly, heat preservation stirring reaction is carried out at a temperature of 35 °C for 40 h; After the reaction is completed, the product components are filtered, and the obtained filter cake is washed 3 times with distilled water and ethanol respectively, and then after drying treatment, the obtained solid powder is mixed and stirred evenly with silicon powder with a mass 4 times that of it, and finally high-temperature treatment is carried out in an argon atmosphere, and the obtained product is the carrier substrate; Among them, the high-temperature treatment process is as follows: First, heat treatment is carried out at a temperature of 1000 °C for 3 h, and then heat treatment is carried out at a temperature of 1600 °C for 3 h; Among them, when adjusting the temperature, the heating rate is set at 10 °C / min.

[0053] Example 3

[0054] The production method of a high-temperature resistant gear oil with light preservation performance provided in this example is basically the same as that in Example 1, except that: the specific composition of the raw materials used and the preparation method of the functional additives are not completely the same, and the specific composition of the raw materials used and the preparation method of the functional additives in this example are as follows:

[0055] An electric vehicle axle gear oil, the gear oil is composed of the following raw materials in parts by weight: 110 parts of base oil, 1.2 parts of N, N-dibutylaminotoluene triazole, 12 parts of Afton HiTEC 355 viscosity modifier, 15 parts of polyol ester TM 143, 3 parts of pour point depressant, 2 parts of compound antioxidant, 2.5 parts of demulsifier D114, 1.5 parts of benzotriazole, 6 parts of sulfurized isobutene, 0.6 parts of dimethyl silicone oil and 8 parts of functional additive;

[0056] The preparation method of the functional additive includes the following steps: uniformly disperse the pretreated carrier substrate in toluene according to a solid-liquid ratio of 30 g / L, add a silane coupling agent KH-580 with a mass 0.4 times that of the pretreated carrier substrate, mix and stir evenly, and then reflux and stir for 6 h; after the reaction is completed, lower the temperature of the product components to 65 °C, and then add a modifier with a mass 1.2 times that of the pretreated carrier substrate, an antioxidant GM with a mass 0.8 times that of the pretreated carrier substrate, and a dibutyltin dilaurate with a mass 0.12 times that of the pretreated carrier substrate, mix and stir evenly, and then keep stirring and reacting at a temperature of 65 °C for 8 h; after the reaction is completed, filter and vacuum dry the product components in sequence, and the obtained product is the functional additive.

[0057] The preparation method of the modifier is: uniformly disperse 5-isocyanatoisophthaloyl chloride in acetone with a mass 5 times that of it, and then add 2,6-di-tert-butyl-4-hydroxymethylphenol with a molar amount 3 times that of 5-isocyanatoisophthaloyl chloride in an ice-water bath environment, mix and stir evenly, and then stir and react at a temperature of 30 °C for 8 h; after the reaction is completed, the modifier is obtained.

[0058] The preparation method of the pretreated carrier substrate is: soak the carrier substrate in a hydrofluoric acid solution with a mass 15 times that of it and a concentration of 30 wt% for 25 h, and then filter out the carrier substrate and wash it 5 times with deionized water; after washing, soak it in a hydrogen peroxide aqueous solution with the same mass and concentration as the hydrofluoric acid solution for 60 min, and then filter and naturally dry it to obtain the pretreated carrier substrate.

[0059] The preparation method of the carrier substrate includes the following steps:

[0060] Step 1: Uniformly disperse nano-zirconia microspheres in ethanol according to a solid-liquid ratio of 50 g / L, then add 3-aminopropyltrimethoxysilane with a mass 0.2 times that of the nano-zirconia microspheres, stir evenly and reflux for 5 h; after the reaction is completed, centrifuge, wash with water and dry the reaction product in sequence; store the obtained modified nano-zirconia microspheres for later use;

[0061] Step 2: Put the modified nano-zirconia microspheres into DMF according to a solid-liquid ratio of 80 g / L, then add carboxylated graphene with a mass 3 times that of the modified nano-zirconia, 10 times of dicyclohexylcarbodiimide, and 1.5 times of N,N-dimethyl-4-pyridinamine, mix and stir evenly, and keep stirring at 40 °C for 50 h; after the reaction is completed, filter the components of the product, wash the obtained filter cake with distilled water and ethanol 3 times respectively, and then after drying, mix and stir evenly the obtained solid powder with silicon powder with a mass 5 times that of it, and finally perform high-temperature treatment in an argon atmosphere, and the obtained is the carrier substrate; among them, the high-temperature treatment process is: first heat-treat at 1200 °C for 2 h, and then heat-treat at 1800 °C for 2 h; among them, the heating rate is set to 10 °C / min when adjusting the temperature.

[0062] Comparative Example 1: The main difference between this example and Example 1 is that in the process of preparing the functional additive in this example, an equal amount of modifier is used to replace the antioxidant GM;

[0063] Comparative Example 2: The main difference between this example and Example 1 is that in the process of preparing the functional additive in this example, an equal amount of antioxidant GM is used to replace the modifier;

[0064] Comparative Example 3: The main difference between this example and Example 1 is that in this example, an equal amount of carrier substrate is used to replace the functional additive.

[0065] Comparative Example 4: The main difference between this example and Example 1 is that in this example, an equal amount of nano-zirconia microspheres is used to replace the functional additive.

[0066] Performance Test

[0067] Test the typical physical and chemical indexes of the gear oil samples produced in Examples 1-3 and Comparative Examples 1-4 respectively, and record the obtained test data in the following table:

[0068] Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Test method Copper strip corrosion (100 °C, 3 h) / grade 1a 1a 1a 1a 1a 1b 1b GB / T 5096 Rotating bomb (150 °C) / min 458 467 461 441 438 374 326 SH / T 0193 Oxidation performance (121 °C, 312 h) 100 °C kinematic viscosity increase / % sediment value / mL 1.030.00 0.9800.00 1.050.00 1.160.01 1.190.01 1.270.02 1.320.02 SH / T 0123 Friction coefficient (MTM) Friction coefficient (40 °C) 0.027 0.026 0.026 0.028 0.027 0.027 0.032 MTM micro traction testing machine <![CDATA[Four-ball machine test sintering load (P D ) / N Wear scar diameter (196 N, 60 min, 54 °C, 1800 r / min) / mm]]> 45890.26 46720.25 46830.25 45560.27 45490.26 46020.25 42780.30 GB / T 3142 SH / T 0189

[0069] By comparing and analyzing the relevant data in the table, it can be seen that the gear oil produced by the present invention not only has excellent high-temperature resistance and wear and friction reduction performance, but also has good antioxidant performance. To a certain extent, it reduces the wear degree of the axle gears, extends the service life of the gear oil and also extends the service life of the axle gears, effectively ensuring the grade and quality of the gear oil. This shows that the electric vehicle axle gear oil and its production process provided by the present invention have a broader market prospect and are more suitable for promotion.

[0070] In the description of this specification, the description with reference to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0071] The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of this specification. These embodiments are selected and specifically described in this specification in order to better explain the principles and practical applications of the present invention, so that those skilled in the relevant technical fields can understand and utilize the present invention well. The present invention is only limited by the claims and their full scope and equivalents.

Claims

1. An electric vehicle axle gear oil, characterized in that: The gear oil is composed of the following raw materials in parts by weight: 90-110 parts of base oil, 0.5-1.2 parts of N,N-di-n-butylaminotoluene triazole, 9-12 parts of viscosity modifier, 10-15 parts of polyol ester, 1-3 parts of pour point depressant, 1-2 parts of compound antioxidant, 1.5-2.5 parts of anti-emulsifier, 0.8-1.5 parts of rust inhibitor, 3-6 parts of extreme pressure anti-wear agent, 0.2-0.6 parts of defoamer and 5-8 parts of functional additives; The pour point depressant is prepared by compounding alkyl naphthalene and acrylic acid polymer in a mass ratio of 1:1 to 2; the compound antioxidant is prepared by compounding phenolic antioxidant and amine antioxidant in a mass ratio of 1:1 to 1.5; The preparation method of the functional additive comprises the following steps: uniformly dispersing a pre-treated carrier substrate in toluene at a solid-liquid ratio of 10 to 30 g / L, adding a silane coupling agent KH-580 whose mass is 0.2 to 0.4 times of the pre-treated carrier substrate, mixing and stirring evenly, and then reflux stirring and reacting for 4 to 6 hours; after the reaction is completed, lowering the temperature of the resultant components to 50 to 65° C., and then adding a modifier whose mass is 0.6 to 1.2 times of the pre-treated carrier substrate, an antioxidant GM whose mass is 0.5 to 0.8 times, and dibutyltin dilaurate whose mass is 0.08 to 0.12 times, respectively, mixing and stirring evenly, and then heat-insulating and stirring and reacting at a temperature of 50 to 65° C. for 5 to 8 hours; after the reaction is completed, filtering and vacuum drying the resultant components in turn, and the obtained functional additive is obtained; The preparation method of the modifier is as follows: 5-isocyanate isophthaloyl chloride is uniformly dispersed in acetone with a mass of 3 to 5 times that of acetone, and then 2,6-di-tert-butyl-4-hydroxymethylphenol with a molar amount of 2 to 3 times that of 5-isocyanate isophthaloyl chloride is added in an ice water bath environment, and the mixture is stirred evenly and then reacted at a temperature of 20 to 30° C. for 5 to 8 hours; after the reaction is completed, the modifier is obtained; The preparation method of the pre-treated carrier substrate is as follows: immersing the carrier substrate in a hydrofluoric acid solution with a mass of 10 to 15 times and a concentration of 30 wt% for 20 to 25 hours, then filtering out the carrier substrate and washing it with deionized water for 3 to 5 times; after washing, immersing it in a hydrogen peroxide aqueous solution with a mass and a concentration equal to that of the hydrofluoric acid solution for 40 to 60 minutes, then filtering and naturally drying to obtain the pre-treated carrier substrate; The method for preparing the carrier substrate comprises the following steps: Step 1, uniformly dispersing nano zirconium oxide microspheres in ethanol at a solid-liquid ratio of 20 to 50 g / L, then adding 3-aminopropyltrimethoxysilane in an amount of 0.1 to 0.2 times the mass of the nano zirconium oxide microspheres, stirring evenly and then reflux reacting for 3 to 5 hours; after the reaction is completed, centrifuging, washing and drying the reaction products in sequence; the obtained modified nano zirconium oxide microspheres are stored and reserved; Step 2: Add the modified nano-zirconia microspheres into DMF at a solid-liquid ratio of 50 to 80 g / L, then add carboxylated graphene 2 to 3 times the mass of the modified nano-zirconium oxide, 5 to 10 times the mass of dicyclohexylcarbodiimide, and 1.0 to 1.5 times the mass of N, N-dimethyl-4-pyridinamine, mix and stir evenly, and then keep stirring and react at a temperature of 30 to 40° C. for 30 to 50 hours; after the reaction is completed, filter the resultant components, wash the obtained filter cake with distilled water and ethanol for 2 to 3 times, and then dry the obtained solid powder and mix and stir the obtained solid powder with silicon powder 3 to 5 times the mass of the solid powder, and finally perform high-temperature treatment in an argon atmosphere to obtain a carrier substrate; The high temperature treatment process is: first heat treatment at a temperature of 800-1200°C for 2-3 hours, and then heat treatment at a temperature of 1500-1800°C for 2-4 hours; wherein, when adjusting the temperature, the heating rate is set to 5-10°C / min.

2. The electric vehicle axle gear oil according to claim 1, characterized in that: The base oil is prepared by mixing high-viscosity synthetic base oil, poly-α-olefin base oil and polyester base oil in a ratio of 8 to 10:1:1 to 2; Among them, the high-viscosity synthetic base oil is Indonesian PX20 or Shell X420; the polyalphaolefin base oil is Mobil PAO4 or Mobil PAO6; the polyester base oil is Italian Ite Polyester KL115 or Italian Ite Polyester KL135.

3. The electric vehicle axle gear oil according to claim 1, characterized in that: The viscosity modifier is selected from any one of Afton HiTEC 5777, Afton HiTEC 3339 and Afton HiTEC 355.

4. The electric vehicle axle gear oil according to claim 1, characterized in that: The polyol ester is any one of TM108, TM118 and TM143.

5. The production process of an electric vehicle axle gear oil according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: weighing various raw materials according to the formula amount, and then transferring the base oil, functional additives and defoaming agent into a blending kettle, raising the kettle temperature to 60-70°C and adding the remaining raw materials into the blending kettle while stirring at this temperature, maintaining the kettle temperature at 60-70°C, and continuing to stir at a rate of 600-800r / min for 1-2h, and finally obtaining electric vehicle axle gear oil.