Preparation method of Ta (1-x) RexS2-based solid lubricating material and lubricating coating

Abstract

The invention provides a preparation method of a Ta (1-x) RexS2-based solid lubricating material and a lubricating coating, and particularly relates to the technical field of solid lubricating materials. The preparation process of the Ta (1-x) RexS2-based solid lubricating material comprises the following steps: grinding and mixing tantalum powder, rhenium powder and sulfur powder as main raw materials, heating and sintering to prepare Ta (1-x) RexS2 polycrystalline powder, grinding and mixing the Ta (1-x) RexS2 polycrystalline powder and LiBH4 powder, carrying out heat treatment, dispersing, and carrying out ultrasonic treatment and centrifugal treatment to prepare the Ta (1-x) RexS2-based solid lubricating material, a lubricating coating is prepared on the base material in an air spraying manner; compared with the traditional MoS2-based lubricating material, the Ta (1-x) RexS2-based solid lubricating material prepared by the invention has higher bearing capacity and longer service life, and provides more selection spaces and wider application scenes for taking TMDs as the solid lubricating material.

Description

Technical Field

[0001] The present invention relates to the technical field of solid lubricating materials, and in particular to a Ta 1-x Re x The invention relates to a preparation method of an S2-based solid lubricating material and a lubricating coating. Background Art

[0002] According to statistics, energy loss caused by friction and wear accounts for about one-third of the energy consumed by mechanical equipment. Therefore, reducing friction and wear is very important and urgent. Liquid lubrication is one of the effective methods to reduce friction and wear, but it is prone to leakage, creep and other problems under harsh working conditions such as high speed, high temperature and heavy load, and its performance will be seriously affected. In comparison, solid lubricating materials have advantages such as a wide range of applications and are relatively environmentally friendly, which greatly compensates for the shortcomings of liquid lubrication. Among the many solid lubricating materials, transition metal dichalcogenides (TMDs) have attracted widespread attention due to their unique layered structure and better friction and wear performance under more extreme conditions.

[0003] Compared with other materials used as solid lubricants, TMDs have excellent low-friction properties. The strong covalent bonds within the layers provide the required structural stability, while the weak van der Waals interactions and large separation distances between the layers make them easy to slide. TMDs have been the research focus in the field of industrial tribology for decades. The wide variety of transition metals and the continuous changes in dichalcogenides have led to a very large family of transition metal dichalcogenides. However, most research efforts have focused on binary compounds, with only limited attempts to optimize the performance of materials using the vast chemical space spanned by alloys. Only a limited number of TMDs have been used in the field of solid lubrication. Current transition metal dichalcogenide solid lubricants are mainly based on Mo and W binary systems, such as MoS2.

[0004] Therefore, there is an urgent need for a new TMDs that can be used in the field of solid lubrication, so that it can meet the requirements of extremely low friction coefficient and longer service life under different loads, different speeds and different dual conditions. Summary of the Invention

[0005] The purpose of the present invention is to overcome the shortcomings of the prior art. The present invention uses tantalum powder, rhenium powder and sulfur powder as main raw materials to prepare Ta 1-x Re x S2-based lubricating material, and a lubricating coating was prepared by air spraying; Compared with the traditional MoS2-based lubricating material, the Ta 1-x Re x S2-based lubricating materials have higher load-bearing capacity and service life, providing more options and wider application scenarios for TMDs as solid lubricating materials.

[0006] According to the content of the present invention, on the one hand, there is provided a Ta 1-x Re x A method for preparing an S2-based solid lubricating material, the method comprising: Weigh Ta powder, Re powder and S powder with a molar ratio of Ta:Re:S=(1-x):x:2, grind and mix them for the first time, and then heat and sinter to obtain Ta 1-x Re x S2 polycrystalline powder, where x = 0.3~0.6; LiBH4 powder and Ta 1-x Re x The S2 polycrystalline powder was ground and mixed again in a molar ratio of 1:1. The mixed powder was placed in a tube furnace for heat treatment, dispersed in a dispersion solvent, and ultrasonically treated. After centrifugation, the supernatant obtained was Ta 1-x Re x S2-based solid lubricant.

[0007] Preferably, the particle sizes of Ta powder, Re powder and S powder are 300 mesh, 300 mesh and 325 mesh respectively.

[0008] Preferably, the heating and sintering process is to first seal the initially ground and mixed powder in a quartz tube, and then place it in a muffle furnace for heating and sintering. The heating and sintering process is to heat to 500-550°C at a rate of 5°C / min, keep warm for 3 hours, and then heat to 900-950°C at a rate of 5°C / min, and keep warm for 24 hours.

[0009] Preferably, the heat treatment process is to place the re-ground mixed powder in a quartz tube and evacuate the vacuum to 10 -1 ~10 -6 Pa, and then put the whole into a tube furnace and heat it to 350~400℃ and keep it warm for 1h.

[0010] Preferably, the dispersing solvent is deionized water.

[0011] Preferably, the ultrasonic treatment time is 30-50 min, and the ultrasonic frequency is 40 kHz.

[0012] Preferably, the centrifugal treatment time is 5-15 min, and the rotation speed is 3000-3500 rpm.

[0013] The present invention also provides a method for preparing a lubricating coating, wherein the Ta 1-x Re x S2-based solid lubricant is evenly dispersed to obtain a uniformly mixed Ta 1-x Re xThe S2-based solid lubricant dispersion was ultrasonically treated and then the lubricating coating was prepared by air spraying.

[0014] Preferably, the air spraying specifically includes spraying back and forth twice at a distance of 10 to 15 cm between the spray gun and the substrate, the air pressure of the spray gun is 0.6 to 0.7 MPa, the caliber of the spray gun is 1 to 2 mm, and the thickness of the coating is 20 to 50 μm; the substrate after spraying is placed in a vacuum drying oven for drying to obtain a lubricating coating on the substrate.

[0015] Preferably, the drying temperature of the vacuum drying oven is 60-80° C., and the drying time is 4-8 hours.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Preparation of Ta by the Present Invention 1-x Re x S2-based solid lubricant material has a good lubrication effect as a lubricating coating. It has an extremely low friction coefficient under different loads, different speeds and different dual conditions, and its lubrication performance is better than that of traditional MoS2, ReS2, etc.

[0017] 2. Ta prepared by the present invention 1-x Re x S2-based solid lubricating materials have a long service life and good economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly described below. It should be noted that the drawings described below only relate to some embodiments of the present disclosure and are not intended to limit the present disclosure. Figure 1 It is Ta provided in Example 1 of the present invention 0.5 Re 0.5 XRD pattern of S2 original powder.

[0019] Figure 2 It is Ta provided in Example 1 of the present invention 0.5 Re 0.5 AFM image of S2 dispersion.

[0020] Figure 3 This is the friction coefficient curve of the solid lubricating material provided in Example 1 of the present invention.

[0021] Figure 4 This is a friction coefficient curve of the solid lubricating material provided by Example 2 of the present invention.

[0022] Figure 5 This is the friction coefficient curve of the solid lubricating material provided by Example 3 of the present invention.

[0023] Figure 6 This is a columnar comparison chart of the friction coefficient of the solid lubricating material provided by Example 4 of the present invention under different dual spheres.

[0024] Figure 7 This is a columnar comparison chart of the friction coefficient of the solid lubricating material provided by Example 4 of the present invention under different substrates.

[0025] Figure 8 This is a columnar comparison chart of the friction coefficient of the solid lubricating material provided in Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the embodiments of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by those skilled in the art without creative work also fall within the scope of protection of the present disclosure.

[0027] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the subject matter of the present disclosure belongs. It will be further understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the specification and the relevant art, and will not be interpreted in an idealized or overly formal manner unless otherwise explicitly defined herein. As used herein, a statement that two or more parts are "connected" or "coupled" together shall mean that the parts are joined together either directly or through one or more intermediate components.

[0028] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase "embodiment" in various places in the specification does not necessarily refer to the same embodiment, nor does it necessarily refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0029] The present invention provides a Ta 1-x Re x The preparation method of S2-based solid lubricating material comprises: Ta powder, Re powder and S powder with a molar ratio of Ta:Re:S=(1-x):x:2 are weighed, wherein x is preferably 0.3-0.6, for example, 0.3, 0.4, 0.5, 0.6; after initial grinding to fully mix, the mixture is transferred to a quartz tube and sealed, and heated and sintered in a muffle furnace at a rate of 5°C / min to 500-550°C and then kept warm for 3h, and then heated to 900-950°C and kept warm for 24h to obtain Ta 1-x Re x S2 polycrystalline powder; Ta 1-x Re x S2 polycrystalline powder is taken out from the quartz tube LiBH4 powder and Ta 1-x Re x The S2 polycrystalline powder was ground again in a molar ratio of 1:1 to make it fully mixed, and the mixed powder was placed in a quartz tube and vacuumed to make the vacuum degree in the quartz tube 10 -1 ~10 -6 Pa, and then the whole is placed in a tube furnace for heat treatment at 350-400 ° C for 1 hour, and then the mixed powder is taken out, dispersed in a dispersion solvent, and ultrasonically treated for preferably 30-50 minutes, for example, 30 minutes, 40 minutes, and 50 minutes, with an ultrasonic frequency of 40kHz, and then centrifuged at 3000-3500 rpm for preferably 5-15 minutes, for example, 5 minutes, 8 minutes, 10 minutes, and 15 minutes, and the supernatant obtained is Ta 1-x Re x S2-based solid lubricant.

[0030] In some embodiments of the present invention, the dispersion solvent is deionized water. Other dispersion solvents may also be used to disperse the mixed powder, which is not specifically limited herein.

[0031] The present invention also provides a method for preparing a lubricating coating, wherein the statically deposited Ta 1-x Re x The S2-based solid lubricant material is first dispersed, and the obtained dispersion is ultrasonically treated for 40 to 60 minutes, with a power of 200 W and a frequency of 40 kHz. The lubricating coating is prepared by air spraying.

[0032] Specifically, a spray gun with an air pressure of 0.6-0.7 MPa and a diameter of 1-2 mm is used to spray the substrate back and forth twice at a distance of 10-15 cm. The spraying thickness is preferably 20-50 μm, for example, 20 μm, 30 μm, 40 μm, or 50 μm. After spraying, the coating is placed in a vacuum drying oven at 60-80°C and dried for 4-8 hours.

[0033] The following is explained with reference to specific embodiments: Example 1

[0034] Take x = 0.5 and prepare a Ta 0.5 Re 0.5 S2-based solid lubricating materials; Ta powder, Re powder, and S powder were weighed according to a molar ratio of 0.5:0.5:2, ground to mix thoroughly, and then transferred to a sealed quartz tube. A muffle furnace was used to heat the tube at a rate of 5°C / min to 500°C and then kept at this temperature for 3 hours. The temperature was then raised to 900°C and kept at this temperature for 24 hours to obtain Ta. 0.5 Re 0.5 The X-ray diffraction (XRD) analysis diagram of S2 polycrystalline powder is as follows: Figure 1 As shown; The obtained polycrystalline powder was taken out from the quartz tube and 0.001 mol Ta was weighed. 0.5 Re 0.5 S2 powder; weigh 0.001 mol LiBH4 powder, grind it to make it fully mixed, and then transfer it to a quartz tube for vacuum; put the vacuumed quartz tube into a tube furnace and heat it to 350℃, keep it warm for 1 hour, then take out the powder, add 40ml deionized water, ultrasonically treat it for 30 minutes, and then centrifuge it at 3000rmp for 5 minutes. The supernatant is used as the solid lubricant material. The atomic force microscope (AFM) image of its dispersion is shown below. Figure 2 shown.

[0035] The prepared solid lubricating material is sprayed on the 718 alloy by air spraying to form a lubricating coating; Use a spray gun with an air pressure of 0.7 MPa and a diameter of 2 mm to spray the 718 alloy back and forth twice at a distance of 10 cm to a spray thickness of 30 μm. After spraying, place the coating in a vacuum drying oven at 70°C for 6 hours to obtain a lubricating coating on the 718 alloy. The friction and wear performance of the lubricating coating under different loads was evaluated by a UMT-Tribolab (Bruker) friction and wear tester. The tester had a Si3N4 ceramic ball as the dual ball, a load of 1-40 N, a frequency of 1 Hz, and a running time of 10 min. The measured friction coefficient curve is shown in the figure below. Figure 3 As shown in the figure, the measured friction coefficient of the solid lubricant material is small and the data is stable. Compared with the unlubricated condition, the lubricating coating can reduce the friction coefficient by more than 90%.

[0036] Example 2 Preparation of a Ta 0.5 Re 0.5 S2-based solid lubricant material, and the prepared solid lubricant material is sprayed on the 718 alloy by air spraying to form a lubricating coating, the process is the same as that of Example 1; The friction and wear performance of the lubricating coating at different frequencies was evaluated by a UMT-Tribolab (Bruker) friction and wear tester. The tester had a Si3N4 ceramic ball as the dual ball, a load of 2N, a frequency of 0.5-5Hz, and a running time of 10 minutes. The measured friction coefficient curve is shown in the figure below. Figure 4 As shown in the figure, the friction coefficient of the solid lubricant is small and the data is stable, and it has good lubrication performance under the condition of 0.5~5Hz.

[0037] Example 3 Preparation of a Ta 0.5 Re 0.5 S2-based solid lubricant material, and the prepared solid lubricant material is sprayed on the 718 alloy by air spraying to form a lubricating coating, the process is the same as that of Example 1; The service life of the lubricating coating was evaluated by a UMT~Tribolab (Bruker) friction and wear tester. The tester used Si3N4 ceramic balls as the dual balls, a load of 5N, and a frequency of 3Hz. The measured friction coefficient curve is shown in the figure below. Figure 5 As shown in the figure, the lubrication effect of the solid lubricant can last for more than 100,000 cycles, and the friction coefficient is always stable at around 0.05 and 1.08×10 5 After the first cycle, the friction coefficient begins to increase.

[0038] Example 4 Preparation of a Ta 0.5 Re 0.5 S2-based solid lubricant material, and the prepared solid lubricant material is sprayed on 718 alloy and 316 stainless steel by air spraying to form a lubricating coating, the process is the same as that of Example 1; The influence of substrate and ball type on lubrication performance was evaluated by a UMT-Tribolab (Bruker) friction and wear tester. The balls were Si3N4 ceramic and GCr15 steel, with a load of 1-10 N and a frequency of 1 Hz. The friction coefficient bar graph is shown in Figure 2. Figure 6 and Figure 7 As shown, Figure 6 This is a columnar comparison chart of the friction coefficients of solid lubricating materials measured under different dual balls. Figure 7 This is a bar chart comparing the friction coefficients of solid lubricants measured on different substrates, indicating that the lubricating effect of the lubricant is only related to the material itself.

[0039] Comparative Example 1 MoS2 coating was prepared on 718 alloy by air spraying. The lubricating effect of MoS2 coating was then evaluated using UMT-Tribolab (Bruker) under different loads. The dual ball of the test machine was Si3N4, the load was 1-40 N, and the frequency was 1 Hz. The friction coefficient test results are as follows Figure 8 As shown, under 1~20 N load, MoS2 and Ta 0.5 Re 0.5 S2 has a very low friction coefficient; when the load rises to 40N, Ta 0.5 Re 0.5 S2 still has a good lubricating effect, while the friction coefficient of MoS2 rises to about 0.3.

[0040] Therefore, 0.5 Re 0.5 Compared with traditional MoS2-based lubricating materials, S2 solid lubricating materials have higher load-bearing capacity and service life, providing more options and wider application scenarios for TMDs as solid lubricating materials.

[0041] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A Ta 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The preparation method comprises: Weigh Ta powder, Re powder and S powder with a molar ratio of Ta:Re:S=(1-x):x:2, grind and mix them for the first time, and then heat and sinter to obtain Ta 1-x Re x S2 polycrystalline powder, where x = 0.3~0.6; LiBH4 powder and Ta 1-x Re x The S2 polycrystalline powder was ground and mixed again in a molar ratio of 1:

1. The mixed powder was placed in a tube furnace for heat treatment, dispersed in a dispersion solvent, and ultrasonically treated. After centrifugation, the supernatant obtained was Ta 1- x Re x S2-based solid lubricant.

2. A Ta according to claim 1 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The particle sizes of the Ta powder, the Re powder and the S powder are 300 mesh, 300 mesh and 325 mesh respectively.

3. A Ta according to claim 1 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The heating and sintering process is as follows: the powder obtained by primary grinding and mixing is first sealed in a quartz tube, and then placed in a muffle furnace for heating and sintering, heating to 500-550°C at a rate of 5°C / min, keeping the temperature for 3 hours, and then heating to 900-950°C at a rate of 5°C / min, keeping the temperature for 24 hours.

4. A Ta according to claim 1 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The heat treatment process is to place the re-ground mixed powder in a quartz tube and evacuate the vacuum to 10 -1 ~10 -6 Pa, and then put the whole into a tube furnace and heat it to 350~400℃ and keep it warm for 1h.

5. A Ta according to claim 1 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The dispersing solvent is deionized water.

6. A Ta according to claim 1 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The ultrasonic treatment time is 30-50 min, and the ultrasonic frequency is 40 kHz.

7. The Ta according to claim 1 1-x Re x The preparation method of S2-based solid lubricating material is characterized in that: The centrifugal treatment time is 5-15 minutes, and the rotation speed is 3000-3500 rpm.

8. A method for preparing a lubricating coating, characterized in that: The Ta prepared by the preparation method according to any one of claims 1 to 7 1-x Re x S2-based solid lubricant is evenly dispersed to obtain a uniformly mixed Ta 1-x Re x The S2-based solid lubricant dispersion was ultrasonically treated and then the lubricating coating was prepared by air spraying.

9. The method for preparing a lubricating coating according to claim 8, characterized in that: The air spraying specifically includes spraying the substrate with a spray gun at a distance of 10 to 15 cm and back and forth twice, with an air pressure of 0.6 to 0.7 MPa, a caliber of 1 to 2 mm, and a coating thickness of 20 to 50 μm; the substrate after spraying is placed in a vacuum drying oven for drying to obtain a lubricating coating on the substrate.

10. The method for preparing a lubricating coating according to claim 9, characterized in that: The drying temperature of the vacuum drying oven is 60-80° C., and the drying time is 4-8 hours.

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