High-efficiency anti-wear lubricating grease composition for heavy-load working condition and preparation method thereof

Abstract

The invention discloses a high-efficiency anti-wear lubricating grease composition for heavy-load working conditions and a preparation method thereof. The high-efficiency anti-wear lubricating grease composition comprises the following components in parts by weight: 0.5-1.5 parts of MoS2GF composite material; 15-25 parts of an anti-wear reagent at extreme pressure; 0.05 to 1 part of a metal deactivator; 1-3 parts of an antioxidant; 10 to 15 parts of a composite lithium thickening agent; 5-15 parts of mineral oil; and the balance of synthetic oil. The lubricating grease is not only suitable for high-load and high-impact heavy-duty bearings, gears and other transmission parts, but also can be used for high-temperature, high-speed and other harsh working conditions, and has good engineering applicability and reliability.

Description

Technical Field

[0001] This invention belongs to the field of lubricating grease technology, and in particular relates to a high-efficiency anti-wear lubricating grease composition for heavy-duty working conditions and its preparation method. Background Technology

[0002] Under heavy-duty operating conditions, friction pairs in mechanical equipment are subjected to extremely high contact stress and impact loads, placing higher demands on the anti-wear properties, extreme pressure properties, and mechanical stability of lubricating greases. Traditional lubricating greases often fail to maintain stable lubrication performance under extreme conditions due to insufficient oil film strength and uneven dispersion of solid additives. Therefore, developing a lubricating grease that combines a high-strength lubricating film, excellent anti-wear properties, and good high-temperature stability has significant engineering application value. Summary of the Invention

[0003] In view of this, the present invention aims to provide a high-efficiency anti-wear grease composition for heavy-duty working conditions and a method for preparing the same, in order to solve at least one technical problem in the prior art.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows: A high-efficiency anti-wear grease composition for heavy-duty working conditions, comprising, by weight: 0.5-1.5 parts of MoS2GF composite material; 15-25 parts of extreme pressure anti-wear agent; Metal deactivating agent 0.05-1 part; Antioxidant 1-3 parts; 10-15 parts of composite lithium thickener; 5-15 parts mineral oil; Synthetic oil balance.

[0005] Furthermore, the preparation method of MoS2GF composite material includes the following steps: S1: Pre-treat the glass fiber and modify the surface of the glass fiber to obtain pre-treated glass fiber; S2: Dissolve the molybdenum source and sulfur source in deionized water, add polyethylene glycol, and stir until homogeneous to obtain a precursor solution; S3: Add the pretreated glass fiber from step S1 to the precursor solution prepared in step S2, disperse it evenly, transfer it to a high-pressure reactor, carry out a solvothermal reaction, and obtain the MoS2GF composite material after post-treatment.

[0006] This self-made additive (MoS2GF) is composed of nano-sized flower-shaped molybdenum disulfide clusters and glass fibers through a special process (MoS2-GF). Its innovation lies in the excellent synergistic effect of the composite material under harsh friction conditions of heavy load and extreme pressure. Specifically, the grease can form a high-strength solid lubricating film with repair function on the surface of the friction pair. The formation and function of this film is a dynamic, phased process: First, under initial contact or medium-to-high loads, the rod-shaped glass fibers effectively disperse contact stress and provide rigid support, while the flower-shaped molybdenum disulfide acts as an auxiliary support point, jointly enhancing the oil film strength and extreme pressure bearing capacity. Subsequently, when the load rapidly increases to a critical state, the glass fibers undergo controllable micro-fracture, and the generated micro-nano particles precisely fill the micro-cracks and defects on the metal surface caused by stress concentration, playing a role in repairing and smoothing the surface. At the same time, the flower-shaped molybdenum disulfide clusters are also crushed and spread out, forming multi-layered, easily shearable MoS2 disulfide sheets. These sheets cover the friction interface, thereby playing an easily shearable role in the sliding friction process, ultimately achieving a significant reduction in the coefficient of friction and a qualitative change in anti-wear performance. In addition, the composite filler has little impact on other properties of the composite lithium-based grease; the grease still possesses excellent high-temperature resistance and colloidal stability.

[0007] Further, the pretreatment of glass fiber in step S1 includes placing the glass fiber in a solution of anhydrous ethanol and acetone, ultrasonically cleaning it, then repeatedly washing it with deionized water, and drying it at 80°C. Preferably, the volume ratio of anhydrous ethanol to acetone is 1:0.5-1.5. The modification of glass fiber in step S1 includes immersing the pretreated glass fiber in an alkaline solution, etching it at room temperature for 20-28 hours, washing it thoroughly with deionized water until neutral, and drying it to obtain the pretreated glass fiber.

[0008] Furthermore, the molybdenum source in step S2 is ammonium molybdate tetrahydrate; And / or, the sulfur source in step S2 is thiourea; And / or, the stirring speed in step S2 is 400-600 rpm, and the stirring time is 8-12 min.

[0009] Furthermore, in step S3, the temperature of the solvothermal reaction is 170-190℃, and the reaction time is maintained at a constant temperature for 14-16 h. The post-processing in step S3 includes washing several times and drying the obtained solid product under vacuum at 70-90°C to obtain the MoS2GF composite material.

[0010] Furthermore, the extreme pressure anti-wear agent is selected from one or more of the following: triphenyl thiophosphate, tricresyl phosphate, aminothiocarbamate, ammonium thiophosphate, and isobutylene sulfide.

[0011] Furthermore, the metal deactivator is selected from one or two of N,N-di-n-butylaminomethylenetriazole and benzotriazole derivatives.

[0012] Furthermore, the antioxidant is selected from one or both of 2,6-di-tert-butyl-p-methylphenol and octyl / butyl diphenylamine.

[0013] Furthermore, the composite lithium grease thickener is prepared by saponifying lithium hydroxide, dodecyl stearic acid, and sebacic acid at 90-110℃ for 3 hours, refining at 215-220℃ for 5-10 minutes, cooling from 215-220℃ to 180-190℃ in a very short time, and finally naturally cooling to room temperature, followed by grinding 3-5 times. This thickener has a stable structure and provides good mechanical stability and high-temperature adaptability. Based on this, a comprehensive and synergistic additive system is formulated, the core of which is a self-developed composite extreme pressure anti-wear agent.

[0014] Compared with the prior art, the high-efficiency anti-wear grease composition for heavy-duty working conditions and its preparation method described in this invention have the following advantages: 1. This application introduces a self-developed nanocomposite material (MoS2GF) to form a solid lubricating film on the friction surface, possessing both high-strength support and self-healing functions. Under heavy load and extreme pressure conditions, this composite material can work synergistically in stages: glass fibers first provide rigid support and stress dispersion; under extremely high loads, controllable micro-fracture occurs, filling surface micro-cracks; simultaneously, molybdenum disulfide spreads to form a shear-friendly lubricating layer, significantly reducing the coefficient of friction and improving wear resistance. Tests show that this grease exhibits a significantly reduced wear scar diameter and a more stable coefficient of friction in heavy load simulation tests.

[0015] 2. This application uses a composite lithium-based thickener (dodecyl stearic acid / sebacic acid composite system), which has a stable structure and is not easy to soften or leak at high temperatures, ensuring that the grease maintains good colloidal stability and mechanical stability under high temperature and heavy load conditions.

[0016] 3. This application uses a scientific compounding of composite extreme pressure anti-wear agent and various functional additives (antioxidants, metal deactivators, etc.) to form a synergistically enhanced lubrication protection system, which improves extreme pressure anti-wear performance without affecting other physical and chemical properties of the grease.

[0017] 4. This application uses self-made MoS2 2- The preparation process of GF composite material is simple and mild. The morphology and loading of the composite material can be controlled by adjusting the reaction parameters, making it suitable for large-scale preparation. In addition, the composite material has good dispersibility in grease and is not easy to settle. Attached Figure Description

[0018] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a microscopic schematic diagram of the MoS2-GF proposed in this invention; Figure 2 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Embodiment 1 proposed in this invention; Figure 3 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Embodiment 1 of the present invention; Figure 4 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Embodiment 2 of the present invention; Figure 5 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Embodiment 2 of the present invention; Figure 6 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Embodiment 3 of the present invention; Figure 7 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Embodiment 3 of the present invention; Figure 8 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Embodiment 4 of the present invention; Figure 9 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Embodiment 4 of the present invention; Figure 10 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Embodiment 5 of the present invention; Figure 11 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Embodiment 5 of the present invention; Figure 12 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Embodiment 6 of the present invention; Figure 13 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Embodiment 6 of the present invention; Figure 14 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Comparative Example 1 proposed in this invention. Figure 15 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Comparative Example 1 proposed in this invention. Figure 16 This is a schematic diagram of the wear scar morphology of the heavy-load simulation program in Comparative Example 2 proposed in this invention. Figure 17 This is a schematic diagram of the friction coefficient in the heavy-load simulation program of Comparative Example 2 proposed in this invention; Figure 18 This is a schematic diagram of the wear scar morphology in the heavy-load simulation program of Comparative Example 3 proposed in this invention. Figure 19 This is a schematic diagram of the friction coefficient of the heavy-load simulation program in Comparative Example 3 proposed in this invention. Detailed Implementation

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0020] The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] In the following examples, MoS2-GF is prepared in the laboratory ( Figure 1 Acidic phosphate amine salts were purchased from Shenyang Hualun Lubricating Oil Additives Co., Ltd., code T308; triphenyl thiophosphate was purchased from Jinzhou Shengda Chemicals Co., Ltd., code T309; tricresyl phosphate was purchased from Zibo Huihua Petroleum Additives Co., Ltd., code T306; aminothiocarbamate was purchased from Shenyang Hualun Lubricating Oil Additives Co., Ltd., code T323; dialkyl dithiophosphate (imported product) was purchased from BASF, code IR353. N,N-Di-n-butylaminomethylenetriazole was purchased from Jinzhou Xinxing Petroleum Additives Co., Ltd., code T551; benzotriazole derivatives were purchased from Changsha Wangcheng Petrochemical Co., Ltd., code T553. 2,6-Di-tert-butyl-p-methylphenol was purchased from Jinzhou Xinxing Petroleum Additives Co., Ltd., code T501; octyl / butyl diphenylamine was purchased from Jinzhou Xinxing Petroleum Additives Co., Ltd., code T557. 150BS base oil was purchased from IRPC, Thailand; PAO base oil was purchased from Mobil. T321 is self-sulfurized isobutylene, purchased from Shenyang Hualun Lubricating Oil Additives Co., Ltd.

[0022] DPU-C is a polyurea product purchased from Shandong Yiderun International Trade Co., Ltd.

[0023] Preparation process of self-made extreme pressure anti-wear agent: 1. Pretreatment and surface modification of glass fiber (GF) First, the glass fiber is cleaned and etched to remove surface impurities and increase its reactivity: Cleaning: GF was placed in a solution of anhydrous ethanol and acetone in a 1:1 volume ratio and ultrasonically cleaned. It was then repeatedly washed with deionized water and dried at 80°C.

[0024] Alkali etching: Immerse the cleaned GF in a 20-80 g / L NaOH solution and etch for 24 h at room temperature. After the reaction is complete, wash thoroughly with deionized water until neutral, and dry to obtain pretreated GF for later use.

[0025] 2. Preparation of the reaction precursor solution Weigh 4 g of ammonium molybdate tetrahydrate (as the molybdenum source) and 8 g of thiourea (as the sulfur source) and place them in a beaker. Add 12 mL of deionized water and stir at 500 rpm for 10 min to allow them to initially dissolve. Then, slowly add polyethylene glycol-400 (PEG400) dropwise while continuing to stir until a homogeneous precursor mixture solution is formed.

[0026] 3. Synthesis of MoS2-GF The pretreated GF and 10 mL of deionized water were added to the above precursor solution. Subsequently, the mixture was treated to ensure that the GF was fully dispersed and mixed with the precursor.

[0027] The uniformly mixed slurry was transferred to a high-pressure reactor lined with polytetrafluoroethylene and subjected to a solvothermal reaction in an oven at 180°C for 15 h.

[0028] 4. Post-processing of the product After the reaction was complete, the reactor was allowed to cool naturally to room temperature. The reaction product was then removed and washed several times to remove residual ions and organic impurities. Finally, the obtained solid product was vacuum dried at 80°C to obtain the target product, MoS2-GF nanofiller.

[0029] The composite lithium grease thickener is prepared by saponifying lithium hydroxide, dodecyl stearic acid and sebacic acid at 100°C for 3 hours, refining at 215°C for 8 minutes, cooling from 215°C to 185°C in a very short time, and finally naturally cooling to room temperature and then grinding it 4 times.

[0030] Implementation Column 1: MoS2-GF 1.0%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0031] Implement Column 2: MoS2-GF 2.0%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO (PAO100 and PAO40) balance.

[0032] Implement column 3: MoS2-GF 3.0%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0033] Example 4 MoS2-GF 1.0%, T321 (sulfurized isobutylene) 2.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0034] Example 5 MoS2-GF 1.0%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 2.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0035] Example 6 MoS2-GF 1.0%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 3.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0036] Comparison Column 1: T321 (Isobutylene Sulfide) 1.0%, T309 (Triphenyl Phosphate) 1.0%, T306 (Tricresol Phosphate) 2.0%, T323 (Aminothiocarbamate) 1.0%, T551 (Benzotriazolium Derivative) 0.10%, T501 (2,6-Di-tert-butyl-p-methylphenol) 0.5%, T557 (Octo-Butyl Diphenylamine) 1.0%, Composite Lithium Grease Thickener 10%, Mineral Oil (150BS) 10%, PAO Balance.

[0037] Comparison Column 2: MoS21%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0038] Comparison Column 3: Glass fiber (GF) 1%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, composite lithium grease thickener 10%, mineral oil (150BS) 10%, PAO balance.

[0039] Comparative Example 4 MoS2-GF 1.0%, T321 (sulfurized isobutylene) 1.0%, T309 (triphenyl thiophosphate) 1.0%, T306 (tricresol phosphate) 2.0%, T323 (aminothiocarbamate) 1.0%, T551 (benzotriazole derivative) 0.10%, T501 (2,6-di-tert-butyl-p-methylphenol) 0.5%, T557 (octyl / butyl diphenylamine) 1.0%, thickener (DPU-C) 10%, mineral oil (150BS) 10%, PAO balance.

[0040] Key performance comparisons of the embodiments and comparative examples The anti-wear and anti-fretting wear properties of the examples and comparative examples were investigated.

[0041] The wear resistance was assessed using a four-ball testing machine from Xiamen Tianji. Under conditions of 784 N, 60 min, 75 ℃, and 1200 r / min, the wear scar diameter was used to demonstrate the wear resistance of the grease, as shown in Table 1.

[0042] Table 1 The performance under heavy load was assessed using a self-developed method. The test was conducted at 1,500 N, 100 °C, 1 mm, with a frequency cyclic program (start-up phase: frequency linearly increases from 1 Hz to 100 Hz in 10 seconds; high-speed phase: frequency held at 100 Hz for 1 second; stop phase: frequency linearly decreases from 100 Hz to 1 Hz in 10 seconds; stationary phase: frequency held at 1 Hz for 1 second), 100 cycles. The size, morphology, wear condition, and coefficient of friction of the steel ball friction pair demonstrated the grease's performance under heavy load. Figure 2-13 As shown.

[0043] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-efficiency anti-wear grease composition for heavy-duty operating conditions, characterized in that: Included by weight: 0.5-1.5 parts of MoS2GF composite material; 15-25 parts of extreme pressure anti-wear agent; Metal deactivating agent 0.01-0.05 parts; Antioxidant 1-3 parts; 10-15 parts of composite lithium thickener; 5-15 parts mineral oil; Synthetic oil balance.

2. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: The preparation method of MoS2GF composite material includes the following steps: S1: Pre-treat the glass fiber and modify the surface of the glass fiber to obtain pre-treated glass fiber; S2: Dissolve the molybdenum source and sulfur source in deionized water, add polyethylene glycol, and stir until homogeneous to obtain a precursor solution; S3: Add the pretreated glass fiber from step S1 to the precursor solution prepared in step S2, disperse it evenly, transfer it to a high-pressure reactor, carry out a solvothermal reaction, and obtain the MoS2GF composite material after post-treatment.

3. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: The pretreatment of glass fiber in step S1 includes placing the glass fiber in a solution of anhydrous ethanol and acetone, ultrasonically cleaning it, then repeatedly washing it with deionized water, and drying it at 80°C. Preferably, the volume ratio of anhydrous ethanol to acetone is 1:0.5-1.

5. The modification of glass fiber in step S1 includes immersing the pretreated glass fiber in an alkaline solution, etching it at room temperature for 20-28 hours, washing it thoroughly with deionized water until neutral, and drying it to obtain the pretreated glass fiber.

4. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: The molybdenum source in step S2 is ammonium molybdate tetrahydrate; And / or, the sulfur source in step S2 is thiourea; And / or, the stirring speed in step S2 is 400-600 rpm, and the stirring time is 8-12 min.

5. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: In step S3, the temperature of the solvothermal reaction is 170-190℃, and the reaction time is maintained at a constant temperature for 14-16 h. The post-processing in step S3 includes washing several times and drying the obtained solid product under vacuum at 70-90°C to obtain the MoS2GF composite material.

6. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: Extreme pressure anti-wear agents are selected from one or more of the following: triphenyl thiophosphate, tricresyl phosphate, aminothiocarbamate, ammonium thiophosphate, and isobutylene sulfide.

7. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: The metal deactivator is selected from one or two of N,N-di-n-butylaminomethylenetriazole and benzotriazole derivatives.

8. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: The antioxidant is selected from one or both of 2,6-di-tert-butyl-p-methylphenol and octyl / butyl diphenylamine.

9. The high-efficiency anti-wear grease composition for heavy-duty working conditions according to claim 1, characterized in that: The composite lithium-based grease thickener is prepared by saponifying lithium hydroxide, dodecyl stearic acid and sebacic acid at 90-110℃ for 3 hours, refining at 215-220℃ for 5-10 minutes, cooling from 215-220℃ to 180-190℃ in a very short time, and finally naturally cooling to room temperature and then grinding 3-5 times.

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