Extreme pressure lubricant, hard alloy cutter grinding oil and preparation method and application of extreme pressure lubricant and hard alloy cutter grinding oil

Abstract

The invention discloses an extreme pressure lubricant, hard alloy cutter grinding oil and a preparation method and application thereof, and relates to the field of metal working fluids. According to the extreme pressure additive provided by the invention, 2, 4, 6-tris (2-pyridyl) triazine (TPTZ) and ethylene glycol with the mass ratio of (1-5): 1 are compounded, the intermolecular acting force in a system is increased, the tribological performance of TPTZ is improved, meanwhile, the high electronegativity of N atoms can promote the extreme pressure lubricant to form an adsorption film on the metal surface, and therefore the strength of a friction film is further improved; after the TPTZ and the ethylene glycol are compounded, the viscosity of the grinding oil can be reduced, and then the friction of the grinding oil to metal during high-speed grinding is reduced, so that the grinding oil obtained by adding the extreme pressure lubricant provided by the invention has excellent anti-wear and lubricating properties, the wear scar diameter is less than 0.311 mm, the friction coefficient is less than 0.082, and the wear resistance of the grinding oil is greatly improved. And the grinding requirements of hard alloy cutters can be met.

Description

Technical Field

[0001] The invention relates to the field of metalworking fluids, and in particular to an extreme pressure lubricant, a cemented carbide tool grinding oil, and a preparation method and application thereof. Background Art

[0002] Cemented carbide refers to an alloy made of carbides (mainly tungsten carbide WC, titanium carbide TiC, tantalum carbide TaC and niobium carbide NbC) and bonding metals through powder metallurgy. Due to its excellent hardness, wear resistance and strength, it is widely used in the preparation of tool materials. In the cutting and forming process of cemented carbide tools, grinding oil is usually required to improve lubricity and reduce heat generation during processing. Currently, commonly used cemented carbide tool grinding oil is usually composed of cycloalkane oil, boundary lubricant and extreme pressure lubricant (also known as "extreme pressure additive", "extreme pressure agent", etc.). Among them, extreme pressure lubricants are generally chlorinated, sulfurized or phosphated additives. These additives have surface reactivity and can react with the surface of the tool to form a chemical reaction film, which plays a good lubricating role.

[0003] However, the three commonly used extreme pressure lubricants are still insufficient in improving the anti-wear and lubrication properties of grinding oils, and these three extreme pressure agents also have different disadvantages. For example, chlorinated additives release a small amount of hydrogen chloride during use, which can easily cause metal corrosion; sulfide additives may stain the workpiece, which is not conducive to processing; phosphating additives have a worse lubrication effect than chlorinated and sulfide additives, and are corrosive when used directly in the form of free acid. Therefore, it is urgent to develop a new extreme pressure lubricant to replace the three traditional lubricants. Summary of the invention

[0004] In order to solve the problem that the existing extreme pressure lubricants are insufficient in improving the anti-wear performance and lubrication performance of grinding oil, the present invention provides an extreme pressure lubricant formed by compounding 2,4,6-tri(2-pyridyl)triazine (TPTZ) and ethylene glycol in a specific ratio. Through the synergistic effect between the two, the obtained grinding oil can have excellent anti-wear performance and lubrication performance.

[0005] Another object of the present invention is to provide a cemented carbide tool grinding oil.

[0006] Another object of the present invention is to provide a method for preparing cemented carbide tool grinding oil.

[0007] Another object of the present invention is to provide an application of cemented carbide tool grinding oil.

[0008] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0009] An extreme pressure lubricant comprises 2,4,6-tri(2-pyridyl)triazine and ethylene glycol in a mass ratio of (1-5):1.

[0010] The present invention uses 2,4,6-Tri(2-pyridyl)triazine (2,4,6-Tri(2-pyridyl)-s-triazine, TPTZ) and ethylene glycol in a mass ratio of (1 to 5): 1 as an extreme pressure additive. The synergistic effect between the two can ensure that the grinding oil has excellent lubrication and anti-wear properties, so that the grinding oil can meet the requirements of high temperature and high speed grinding of cemented carbide tools. Specifically, TPTZ has 6 coordinated N atoms, which can form coordination bonds, hydrogen bonds, π-π stacking and CH-π interactions with the hydroxyl groups of ethylene glycol. After the two are compounded, the intermolecular forces within the system can be increased, and the tribological properties of TPTZ can be improved. In addition, the high electronegativity of the N atom can promote the extreme pressure lubricant of the present invention to form an adsorption film on the metal surface, thereby further improving the strength of the friction film and achieving an improvement in the anti-wear properties of the grinding oil. At the same time, the compounding of TPTZ and ethylene glycol can also reduce the viscosity of the grinding oil, thereby reducing the friction of the grinding oil on the metal during high-speed grinding, and improving the lubrication performance of the grinding oil. However, if the viscosity of the grinding oil decreases too much, although the lubrication performance is excellent, the anti-wear performance will also decrease. Therefore, considering the improvement of the anti-wear performance and lubrication performance of the grinding oil, the mass ratio of TPTZ to ethylene glycol should be controlled within the range of (1-5):1.

[0011] It should be noted that the extreme pressure lubricant obtained by compounding TPTZ and ethylene glycol in the present invention also has higher safety and stability, can improve the open flash point of the grinding oil and reduce its evaporation loss, which may also be due to the fact that the extreme pressure agent increases the intermolecular force inside the system. In short, the extreme pressure agent provided by the present invention enables the grinding oil to be applied in more complex processing environments. At the same time, the compounding of TPTZ and ethylene glycol will not produce substances that corrode the metal, and the obtained grinding oil can also form a film on the metal surface to prevent the outside from corroding the metal, so the grinding oil provided by the present invention also has excellent corrosion resistance and rust prevention performance.

[0012] Preferably, the mass ratio of the 2,4,6-tris(2-pyridyl)triazine to ethylene glycol is (2-3):1.

[0013] The present invention also protects a cemented carbide tool grinding oil, which comprises the extreme pressure lubricant.

[0014] Preferably, the cemented carbide tool grinding oil further comprises at least one of a synthetic base oil, a boundary lubricant, a rust inhibitor, a penetrant, and an air release agent.

[0015] In the cemented carbide tool grinding oil formula of the present invention, the addition of the penetrant can reduce the surface tension of the grinding oil, increase its wettability, and enable the grinding oil to form a stronger hydrodynamic lubrication barrier film, thereby playing a better lubricating role. The addition of the air release agent can also change the surface tension of the oil film, so that it can accelerate the speed at which the air dissolved in the lubricating oil is released to the surface of the grinding oil film, and quickly reach vapor-liquid equilibrium at the surface of the oil film, thereby reducing the generation of foam and taking away heat, thereby enhancing the heat dissipation capacity of the grinding oil to a certain extent, and thereby enhancing the stability of the grinding oil.

[0016] More preferably, the cemented carbide tool grinding oil comprises the following components calculated by mass: 60-80 parts of synthetic base oil, 5-15 parts of extreme pressure lubricant, 5-10 parts of boundary lubricant, 0.2-2 parts of rust inhibitor, 1-5 parts of penetrant, and 0.5-2 parts of air release agent.

[0017] The inventors have experimentally confirmed that when the mass fractions of the components in the grinding oil of the present invention are within the above ranges, the obtained grinding oil has better performance. When the mass fractions of the components are not within the above ranges, the performance of the grinding oil decreases to a certain extent.

[0018] More preferably, the mass fraction of the boundary lubricant is 8 to 14 parts.

[0019] The inventors have experimentally confirmed that the mass fraction of the boundary lubricant in the grinding oil of the present invention is 8 to 14 parts, and the obtained grinding oil has better performance.

[0020] More preferably, the synthetic base oil is at least one of trimellitate, trimethylolpropane oleate, pentaerythritol oleate, and poly-α-olefin.

[0021] More preferably, the boundary lubricant is neopentyl polyol complex ester.

[0022] The inventors have experimentally confirmed that when the boundary lubricant in the grinding oil of the present invention is a neopentyl polyol complex ester, the obtained grinding oil has better performance. This is because the neopentyl polyol complex ester and the extreme pressure lubricant in the present invention have a certain interaction, because the complex ester contains some unreacted hydroxyl groups, which can interact with TPTZ. At the same time, the neopentyl polyol complex ester has a large molecular weight and a long carbon chain, and also has a certain extreme pressure lubrication effect.

[0023] In a specific embodiment of the present invention, the neopentyl polyol complex ester is prepared by polymerization of trimethylolpropane, palmitic acid and suberic acid. More specifically, the preparation method of the neopentyl polyol complex ester comprises the following steps: mixing trimethylolpropane, palmitic acid and suberic acid in a molar ratio of 5:4:1, reacting at 200°C for 36 hours under a nitrogen atmosphere, and then filtering and distilling to remove unreacted acid and monoester, thereby obtaining the neopentyl polyol complex ester.

[0024] More preferably, the rust inhibitor is at least one of calcium sulfonate, diethanolamine oleate, and sebacic acid.

[0025] More preferably, the penetrant is at least one of isomeric decanol polyoxyethylene ether, isomeric undecanol polyoxyethylene ether, and isomeric tridecanol polyoxyethylene ether.

[0026] More preferably, the air release agent is at least one of dimethylsiloxane, methylphenylsiloxane and polyacrylate.

[0027] The present invention also protects a method for preparing the above-mentioned cemented carbide tool grinding oil, comprising the following steps:

[0028] Mix all the components at room temperature to obtain cemented carbide tool grinding oil.

[0029] In a specific embodiment of the present invention, the components are mixed and dispersed at room temperature for 30 to 60 minutes to obtain cemented carbide tool grinding oil.

[0030] The present invention also protects the application of the above-mentioned cemented carbide tool grinding oil in the cutting and forming processing of cemented carbide tools.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The cemented carbide tool grinding oil prepared by the extreme pressure agent compounded with TPTZ and ethylene glycol in the present invention was tested. The wear spot diameter was less than 0.311 mm, and the friction coefficient was less than 0.082, indicating that the grinding oil has excellent lubrication and wear resistance and lubrication performance, and can meet the requirements of cemented carbide tool grinding. At the same time, the grinding oil has excellent corrosion and rust prevention capabilities on metals, and also has excellent stability and safety, and can increase the opening flash point of the grinding oil to above 220°C, and reduce the evaporation loss to below 8.5. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents. Among them, the raw material information used in each embodiment and comparative example is as follows:

[0034] Isomeric undecanol polyoxyethylene ether: LE217K was purchased from Guangzhou Xuhe New Material Technology Co., Ltd.

[0035] Dimethylsiloxane: 201-10, purchased from Foshan Huagu Silicone Co., Ltd.

[0036] Methylphenylsiloxane: IOTA-255, purchased from Anhui IOTA Silicone Oil Co., Ltd.

[0037] Neopentyl polyol complex ester: Trimethylolpropane, palmitic acid and suberic acid are mixed in a molar ratio of 5:4:1, reacted at 200°C for 36 hours under a nitrogen atmosphere, and then filtered and distilled to remove unreacted acid and monoester to obtain neopentyl polyol complex ester.

[0038] Examples 1 to 8

[0039] This embodiment provides a method for preparing a series of cemented carbide tool grinding oils having different components and different mass fractions, comprising the following steps:

[0040] Mix all the components and stir at room temperature for 45 minutes to obtain grinding oil.

[0041] The components and mass fractions of the grinding oil in Examples 1 to 8 are specifically shown in Table 1 below:

[0042] Table 1. Components and mass fractions of cemented carbide tool grinding oil in Examples 1 to 8

[0043]

[0044] Comparative Example 1

[0045] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0046] The extreme pressure lubricant is 8 parts of chlorinated paraffin and 4 parts of ethylene glycol.

[0047] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0048] Comparative Example 2

[0049] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0050] The extreme pressure lubricant is 8 parts of 2,4,6-tris(2-pyridyl)triazine and 4 parts of sulfurized lard.

[0051] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0052] Comparative Example 3

[0053] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0054] The extreme pressure lubricant is 12 parts of 2,4,6-tris(2-pyridyl)triazine.

[0055] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0056] Comparative Example 4

[0057] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0058] The extreme pressure lubricant is 12 parts of ethylene glycol.

[0059] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0060] Comparative Example 5

[0061] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0062] The extreme pressure lubricant is 10.28 parts of 2,4,6-tris(2-pyridyl)triazine and 1.72 parts of ethylene glycol.

[0063] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0064] Comparative Example 6

[0065] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0066] The extreme pressure lubricant is 4 parts of 2,4,6-tris(2-pyridyl)triazine and 8 parts of ethylene glycol.

[0067] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0068] Comparative Example 7

[0069] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0070] The extreme pressure lubricant is 2.5 parts of 2,4,6-tris(2-pyridyl)triazine and 1 part of ethylene glycol.

[0071] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0072] Comparative Example 8

[0073] A cemented carbide tool grinding oil, which is different from Example 1 only in that:

[0074] The extreme pressure lubricant is 12.5 parts of 2,4,6-tris(2-pyridyl)triazine and 5 parts of ethylene glycol.

[0075] The preparation method of the grinding oil in this comparative example is consistent with that in Example 1.

[0076] Performance Testing

[0077] Viscosity test: Test the viscosity of grinding oil at 40°C according to GB / T 265-1988.

[0078] Open cup flash point test: Test the open cup flash point of grinding oil according to GB / T 3536.

[0079] Wear spot diameter test: According to GB / T 3142, the anti-wear performance of grinding oil is tested and expressed by the wear spot diameter. The smaller the wear spot diameter, the better the anti-wear performance of the grinding oil.

[0080] Friction coefficient test: The lubrication performance of grinding oil is tested according to SH / T 0762 and expressed as friction coefficient. The smaller the friction coefficient, the better the lubrication performance of grinding oil.

[0081] Corrosion test: Test the copper corrosion performance of grinding oil according to GB / T 5096. The test temperature is 100±1℃ and the test time is 3h±5min.

[0082] Anti-rust test: The anti-rust performance of grinding oil is tested according to method A in GB / T 11143, the test temperature is 60±1℃, and the test period is 24h.

[0083] Evaporation loss test: Test the evaporation loss of grinding oil according to SH / T 0059.

[0084] The performance test data is shown in Table 2 below:

[0085] Table 2. Performance test data of cemented carbide tool grinding oil obtained in Examples and Comparative Examples

[0086]

[0087]

[0088] According to the data of the embodiment in Table 2, it can be seen that after the extreme pressure agent obtained by compounding TPTZ and ethylene glycol with other substances such as rust inhibitors to form cemented carbide tool grinding oil, the viscosity of the grinding oil is moderate, which is similar to the viscosity of general grinding oil (4-6 mm 2 / s), on this basis, the grinding oil of the present invention has excellent anti-wear and lubricating properties, the wear spot diameter is less than 0.311mm, and the friction coefficient is less than 0.082, which can meet the grinding processing requirements of cemented carbide tools. At the same time, the grinding oil has excellent corrosion and rust prevention capabilities on metals, and also has excellent stability and safety. The open flash point of the grinding oil can be increased to above 220°C (the open flash point of the grinding oil in this field is required to be higher than 150°C), and the evaporation loss is reduced to below 8.5.

[0089] According to the data of Examples 1 to 3 and 8, it can be seen that the extreme pressure lubricant provided by the present invention can be applied to different cemented carbide tool grinding oil systems, the synthetic base oil in the grinding oil can be at least one of trimellitate, trimethylolpropane oleate, pentaerythritol oleate, and poly-α-olefin, the rust inhibitor can be at least one of calcium sulfonate, diethanolamine oleate, and sebacic acid, the penetrant can be at least one of isomeric decanol polyoxyethylene ether, isomeric undecanol polyoxyethylene ether, and isomeric tridecanol polyoxyethylene ether, and the air release agent can be at least one of dimethylsiloxane, methylphenylsiloxane, and polyacrylate. According to the data of Examples 1, 4 to 7 and Comparative Examples 5 to 6, when the mass ratio between TPTZ and ethylene glycol is within the preferred range of (2 to 3): 1 (Examples 1, 4 to 5), the obtained grinding oil can have both better anti-wear performance and lubrication performance, the wear spot diameter is as low as 0.256 mm or less, and the friction coefficient is as low as 0.055 or less. When the mass ratio of TPTZ to ethylene glycol is not within the range of (1-5):1 of the present invention (Comparative Examples 5-6), the synergistic effect between TPTZ and ethylene glycol cannot be fully exerted when compounding, so the anti-wear and lubrication properties of the grinding oil are reduced; at the same time, the improper ratio leads to a decrease in the safety and stability of the grinding oil, a decrease in the open flash point of the grinding oil, and an increase in the evaporation loss. However, regardless of whether the ratio is appropriate, the two substances used in the extreme pressure agent of the present invention will not lead to the generation of corrosive substances, so the grinding oil can still have good anti-corrosion and anti-rust properties.

[0090] According to the data of Comparative Examples 1 to 4 in Table 2, it can be seen that the use of other similar substances to replace TPTZ or ethylene glycol in the extreme pressure agent of the present invention (Comparative Examples 1 to 2) will lead to a decrease in the various properties of cemented carbide tool grinding oil, because there is no synergistic effect between other similar substances and TPTZ or ethylene glycol. At the same time, it can be seen from Comparative Examples 1 to 2 that the use of common chlorinated or sulfided extreme pressure agents will cause corrosion to metals. According to Comparative Examples 3 to 4, TPTZ and ethylene glycol are indispensable in the extreme pressure lubricant of the present invention. Among them, when the extreme pressure agent is only TPTZ (Comparative Example 3), the anti-wear and lubrication properties of the grinding oil are reduced, and the open flash point is further reduced, but TPTZ will not cause metal corrosion. At the same time, TPTZ can form a film on the metal surface and delay the rust of the metal. When TPTZ is missing from the system (Comparative Example 4), the film-forming property of the grinding oil on the metal surface decreases, and the improvement of the metal rust prevention ability is greatly reduced. According to Comparative Examples 7 to 8, the addition amount of the extreme pressure agent in the present invention will also affect the various properties of the grinding oil.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. An extreme pressure lubricant, characterized in that: The invention comprises 2,4,6-tri(2-pyridyl)triazine and ethylene glycol in a mass ratio of (1-5):

1.

2. The extreme pressure lubricant according to claim 1, characterized in that: The mass ratio of the 2,4,6-tri(2-pyridyl)triazine to ethylene glycol is (2-3):

1.

3. A cemented carbide tool grinding oil, characterized in that: The components of the cemented carbide tool grinding oil include the extreme pressure lubricant according to claim 1 or 2.

4. The cemented carbide tool grinding oil according to claim 3, characterized in that: The components of the cemented carbide tool grinding oil also include at least one of a synthetic base oil, a boundary lubricant, a rust inhibitor, a penetrant, and an air release agent.

5. The cemented carbide tool grinding oil according to claim 4, characterized in that: It includes the following components calculated by mass: 60-80 parts of synthetic base oil, 5-15 parts of extreme pressure lubricant, 5-10 parts of boundary lubricant, 0.2-2 parts of rust inhibitor, 1-5 parts of penetrant, and 0.5-2 parts of air release agent.

6. The cemented carbide tool grinding oil according to claim 4 or 5, characterized in that: The synthetic base oil includes at least one of trimellitate, trimethylolpropane oleate, pentaerythritol oleate and poly-α-olefin.

7. The cemented carbide tool grinding oil according to claim 4 or 5, characterized in that: The boundary lubricant includes neopentyl polyol complex ester.

8. The cemented carbide tool grinding oil according to claim 4 or 5, characterized in that: The rust inhibitor includes at least one of calcium sulfonate, diethanolamine oleate, and sebacic acid.

9. The method for preparing cemented carbide tool grinding oil according to any one of claims 4 to 8, characterized in that: The steps include: Mix all the components at room temperature to obtain cemented carbide tool grinding oil.

10. Use of the cemented carbide tool grinding oil according to any one of claims 3 to 8 in the cutting and forming processing of cemented carbide tools.

Images