Method for realizing solid interface lubrication based on metal surface diffusion
By constructing an amorphous metal layer with significant thermal diffusion ability on the metal surface, liquid-like deformation is achieved, and the limitation of reducing friction force of metal surfaces in the prior art is solved, especially in atmospheric environments, and at room temperature is achieved solid surface lubrication effect.
Patent Information
- Application Number
- CN202310670142.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-06-07
- Publication Date
- 2024-12-10
AI Technical Summary
The prior art has limitations in reducing the inherent friction of metal surfaces, especially in atmospheric environments, ultralubricating performance is easily lost or limited to specific contact states, and liquid-like deformation behaviors at high temperatures lack direct friction experimental testing.
By constructing an amorphous metal layer with significant thermal diffusion ability on the metal surface, liquid-like deformation is achieved, thereby reducing the friction coefficient in an atmospheric environment of -15°C to 40°C and promoting solid surface lubrication. The amorphous metal layer is obtained by mechanical pressing, metal sputtering or deposition, and is transferred to the surface of the object to be lubricated.
It effectively reduces the friction coefficient of the friction interface, realizes solid surface lubrication in room temperature and atmospheric environment, enhances flow and deformation capabilities, is similar to the deformation behavior of liquids, and is suitable for metal or non-metallic materials.
Smart Images
Figure CN119101859A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of solid interface lubrication, and in particular to a method for achieving solid interface lubrication based on metal surface diffusion. Background Art
[0002] Metal materials are widely used in various industrial equipment, but the friction and wear on the surface of metal materials during service often lead to a large amount of energy consumption, material loss and equipment failure. Therefore, the lubrication of the sliding interface of metal materials is a scientific and technological issue that people have long been concerned about. At present, most of the lubrication between metal friction pairs adopts liquid lubrication, such as adding lubricating oil, lubricating grease, etc. However, how to effectively reduce the intrinsic friction of the metal surface has great scientific and engineering significance.
[0003] In order to reduce the intrinsic friction of metal surfaces, various friction control strategies have been developed and reported.
[0004] Reference 1 found that by introducing a gradient nanostructure on the surface of metallic copper, the roughening and stratification of the metal surface during sliding can be effectively suppressed, reducing the friction coefficient of the copper surface from 0.64 in the initial state to 0.29.
[0005] Reference 2 found that after a layer of ultrafine-grained nickel-tungsten alloy was electroplated on the surface of brass, the plastic deformation of the surface alloy during sliding was dominated by the grain boundaries, and the friction coefficient could be reduced to below 0.2 under low load conditions.
[0006] Reference 3 found that by introducing a layered structure of alternating copper and nickel into the alloy, ultrafine grains will also form on the alloy surface under the action of mechanical force, the number of grain boundaries will increase significantly, and the deformation mediated by the grain boundaries will lead to lower friction.
[0007] Reference 4 found that by depositing regular crystal structured metallic silver films of different thicknesses on the surface of a silicon wafer by ion sputtering, when the film thickness was reduced to 1.5-8.4 nm, the friction coefficient could be reduced from 0.06-0.08 to 0.01-0.03 under ultra-high vacuum, but once exposed to an atmosphere containing nitrogen or oxygen, the friction force increased sharply.
[0008] Reference 5 found that by choosing a special contact state, when a nanoscale tungsten probe slides on a bulk gold surface with a certain pulling force, the gold surface will show very low friction. However, when the normal pressure is further increased, the friction of the gold surface increases sharply.
[0009] The above technical solution has the following disadvantages:
[0010] 1. References 1, 2, and 3 disclose the introduction of gradient nanostructures, nanocrystals, and layered structures on metal surfaces. Although this reduces the intrinsic friction of the metal surface, the friction coefficient of the improved metal surface is still relatively high, for example, the friction coefficient is about 0.1 to 0.3.
[0011] 2. Reference 4 prepares an ultrathin metal film with a regular crystal structure. Although the superlubricity of the metal surface can be observed in an ultra-high vacuum environment, this friction state is very sensitive to the test environment. Once the metal material is exposed to nitrogen or oxygen, the superlubricity will be lost, limiting its application in the atmosphere.
[0012] 3. Reference 5 significantly reduces the friction on the metal surface by selecting a special contact state, but it is worth noting that this special state only exists in the tensile state and is a metastable state under tension, which is of very limited help for real engineering applications (where there is a positive normal pressure).
[0013] It can be seen that the current technical solutions still have many limitations in achieving intrinsic superlubricity on metal surfaces.
[0014] In addition, in reference 6, Krylov et al. proposed the theory of thermal lubrication, predicting that when the temperature is high enough, thermal disturbance will cause the lateral sliding energy barrier to disappear, resulting in almost no interface friction. For metal materials, in reference 7, Frenken et al. found that a nanoscale metal wire would be pulled out during the pull-out process after the probe contacted the metal lead surface at high temperature, indicating that metals have extremely strong deformation ability at high temperatures. Furthermore, in reference 8, Merkle et al. used in situ transmission electron microscopy to observe the wire-drawing behavior of the probe during the sliding separation process on the gold surface at high temperature. Unlike traditional crystalline metal materials, metals show significantly enhanced flow and deformation ability during the wire-drawing process at high temperature, similar to the deformation behavior of liquids. This behavior is also called the liquid-like deformation behavior of metals. Merkle et al. predicted through theoretical calculations that the liquid-like state of metals at high temperatures has the potential to lubricate the metal contact interface, but there is still a lack of direct friction experimental tests. Although metals can lubricate solid sliding interfaces at high temperatures, it is still a great challenge to achieve solid surface lubrication in room temperature atmospheric environments.
[0015] References:
[0016] Reference 1: Chen X, Han Z, Li X, et al. Lowering coefficient of friction in Cu alloys with stable gradient nanostructures. Science advances, 2016, 2: e1601942.
[0017] Reference 2: Argibay N, Furnish T A, Boyce B L, et al. Stress-dependent grain size evolution of nanocrystalline Ni-W and its impact on friction behavior. Scripta Materialia, 2016, 123: 26 - 29.
[0018] Reference 3: Cihan E, Stormer H, Leiste H, et al. Low friction of metallic multilayers by formation of a shear-induced alloy. Sci Rep, 2019, 9: 9480.
[0019] Reference 4: Goto M, Honda F. Film-thickness effect of Ag lubricant layer in the nano-region. Wear, 2004, 256: 1062 - 1071.
[0020] Reference 5: He Y, She D, Liu Z, et al. Atomistic observation on diffusion-mediated friction between single-asperity contacts. Nat Mater, 2022, 21: 173 - 180.
[0021] Reference 6: Krylov S Y, Jinesh K B, Valk H, et al. Thermally induced suppression of friction at the atomic scale. Physical Review E, 2005, 71: 065101.
[0022] Reference 7: Kuipers L, Frenken JW M. Jump to contact, neck formation, and surface melting in the scanning tunneling microscope. Physical Review Letters, 1993, 70: 3907-3910.
[0023] Reference 8: Merkle AP, Marks L D. Liquid-like tribology of gold studied by in situ tem. Wear, 2008, 265: 1864-1869. Summary of the invention
[0024] In order to solve or improve at least one of the problems mentioned in the background technology, the present application provides a method for achieving solid interface lubrication based on metal thermal diffusion.
[0025] The method for achieving solid interface lubrication based on metal surface diffusion provided in the embodiment of the present application includes: constructing a metal material with significant thermal diffusion capacity sufficient to achieve liquid-like deformation in an atmospheric environment of -15°C to 40°C on at least a portion of the surface of the object to be lubricated.
[0026] In at least one embodiment, the metal material having a significant thermal diffusion capacity sufficient to achieve liquid-like deformation is obtained by amorphizing the metal.
[0027] In at least one embodiment, the metal material having a significant thermal diffusion capacity sufficient to achieve liquid-like deformation is formed into an amorphous metal layer, and the atoms in the amorphous metal layer are arranged in a disordered state.
[0028] In at least one embodiment, a method for achieving metal amorphization includes: obtaining an amorphous metal layer by mechanically pressing a metal material.
[0029] In at least one embodiment, a raw material of the amorphous metal layer includes metal.
[0030] In at least one embodiment, the raw material of the amorphous metal layer is silver and / or gold.
[0031] In at least one embodiment, the method includes: transferring the amorphous metal layer to the surface of the object to be lubricated.
[0032] In at least one embodiment, the material of the object to be lubricated is metal or non-metal.
[0033] In at least one embodiment, the pressed metal material is obtained by drying a metal dispersion, or by metal sputtering, metal deposition or metal evaporation.
[0034] In at least one embodiment, the metal material having significant thermal diffusion capacity sufficient to achieve liquid-like deformation is constructed on at least a portion of the surface of the object to be lubricated by direct epitaxial growth, chemical wet growth, or nanoparticle superlattice self-assembly.
[0035] The method for achieving solid interface lubrication by metal thermal diffusion provided in the present application effectively reduces the friction coefficient of the friction interface in an atmospheric environment of, for example, -15°C to 40°C, thereby promoting solid surface lubrication of the friction interface by constructing an amorphous metal material with strong diffusion ability sufficient to achieve liquid-like deformation on the surface of the object to be lubricated. BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Figure 1 A schematic diagram of an amorphous metal layer having significant diffusion capacity sufficient to achieve liquid-like deformation in a method for achieving solid interface lubrication based on metal thermal diffusion according to an embodiment of the present application is shown.
[0037] Figure 2 A schematic diagram of a crystalline metal layer is shown.
[0038] Description of Reference Numerals
[0039] 1 Amorphous metal layer; 2 Crystalline metal layer; 3 Object to be lubricated. DETAILED DESCRIPTION
[0040] The exemplary embodiments of the present application are described below with reference to the accompanying drawings. It should be understood that these specific descriptions are only used to teach those skilled in the art how to implement the present application, and are not intended to exhaust all possible methods of the present application, nor to limit the scope of the present application.
[0041] An embodiment of the present application provides a method for achieving solid interface lubrication based on metal surface diffusion, the method comprising: constructing a metal material with significant diffusion ability sufficient to achieve liquid-like deformation in an atmospheric environment of -15°C to 40°C on at least a portion of the surface of the material to be lubricated to achieve solid interface lubrication. It can be understood that whether there is a significant diffusion ability is determined by whether it can achieve liquid-like deformation. If the material can achieve liquid-like deformation, it can be considered that the material has a significant diffusion ability. Liquid-like deformation can be a significantly enhanced flow and deformation ability, similar to the deformation behavior of a liquid. The metal material with significant thermal diffusion ability sufficient to achieve liquid-like deformation provided in the present application is not limited to functioning only at -15°C to 40°C, and does not mean that it cannot achieve solid interface lubrication in a temperature range other than -15°C to 40°C.
[0042] The metal material with significant thermal diffusion capacity sufficient to achieve liquid-like deformation can be formed into an amorphous metal layer 1, and the amorphous metal layer 1 can be obtained by metal amorphization. The atomic arrangement inside and on the surface of the amorphous metal layer 1 is in a disordered state, such as Figure 1 In contrast, Figure 2 As shown, the atoms in the conventional crystalline metal layer 2 are arranged in an orderly state. For example, the thermal diffusion coefficient of atoms in the amorphous state of the same material is 5 times that of atoms in the crystalline state. When the thermal diffusion coefficient is high enough, liquid-like deformation behavior caused by metal thermal diffusion can also be achieved at room temperature, which can effectively reduce the interface sliding energy barrier and thus reduce the friction coefficient of the material surface.
[0043] like Figure 1 As shown, the material of the object to be lubricated 3 can be metal or non-metallic material. That is, this solution can lubricate the metal surface or the non-metallic material surface. In one embodiment of the present application, the material of the object to be lubricated 3 can be the same as the material of the amorphous metal layer 1 having significant thermal diffusion capacity sufficient to achieve liquid-like deformation.
[0044] The raw materials of the amorphous metal layer 1 with significant thermal diffusion ability include metals. For example, the types of metal materials can be materials with high atomic diffusion ability such as gold and silver. The applicant has found that when gold and silver are used as the material of the amorphous metal layer 1, when silicon, silicon nitride, nitrogen-doped diamond and other materials are used as the friction pair material, the measured friction coefficient is not higher than 0.1. Therefore, it is recommended to use a metal material with high atomic diffusion ability as the material of the amorphous metal layer 1.
[0045] The raw material of the amorphous metal layer 1 having a significant diffusion capacity sufficient to achieve liquid-like deformation can be a single metal or a mixture of various metal materials. It can be understood that for this lubricating material, the friction coefficient does not depend on the type of other materials that form a friction pair with the metal layer 1. The present application takes silicon, silicon nitride, and nitrogen-doped diamond as examples, but does not limit the specific types of other materials that form a friction pair with the amorphous metal layer 1 having a significant diffusion capacity sufficient to achieve liquid-like deformation.
[0046] The amorphous metal layer 1 with significant diffusion ability can be obtained in a variety of ways, including but not limited to mechanical pressing. Taking mechanical pressing as an example, a metal raw material is sandwiched between two flat materials, and pressure is applied to the two base materials to induce the metal material to change from a crystalline state to an amorphous state, thereby obtaining an amorphous metal layer 1 with significant diffusion ability sufficient to achieve liquid-like deformation.
[0047] The structure of the amorphous metal layer 1 having a significant heat diffusion capacity sufficient to achieve liquid-like deformation on at least part of the surface of the object 3 to be lubricated may refer to that after obtaining the amorphous metal layer 1 having a significant heat diffusion capacity sufficient to achieve liquid-like deformation, it is transferred to the object 3 to be lubricated by various existing auxiliary transfer methods. The transfer method includes but is not limited to the existing dry transfer and wet transfer, such as substrate etching method, etc. It can be understood that the method used for transfer is not limited to the method described above.
[0048] The amorphous metal layer 1 with significant thermal diffusion capability exhibits enhanced atomic thermal diffusion capability, which can significantly reduce the friction force on the surface of the amorphous metal layer 1 and thereby lubricate the solid sliding interface.
[0049] Furthermore, when an amorphous metal layer with liquid-like deformation ability is obtained by mechanical pressing, the initial metal material is obtained including but not limited to obtaining it by drying a metal dispersion, or by metal sputtering, metal deposition and metal evaporation, and the initial metal material can also be obtained by other preparation methods.
[0050] Furthermore, the method of constructing the amorphous metal layer 1 with significant diffusion ability on at least part of the surface of the object to be lubricated 3 is not limited to the aforementioned method of first obtaining the amorphous metal layer 1 by pressing and then transferring the amorphous metal layer 1 to the surface of the object to be lubricated 3, and can also be obtained by other mechanical or chemical means. For example, it can be obtained by direct epitaxial growth, chemical wet growth, nanoparticle superlattice self-assembly, etc.
[0051] It can be understood that the aforementioned temperature range of -15°C to 40°C includes the two endpoint values of -15°C and 40°C and any value between the two endpoint values.
[0052] The above is a preferred embodiment of the present application. It should be pointed out that for those skilled in the art, several improvements and modifications can be made without departing from the principles of the present application. These improvements and modifications should also be regarded as the scope of protection of the present application.
Claims
1. A method for achieving solid interface lubrication based on metal surface diffusion, the method comprising: At least part of the surface of the object to be lubricated (3) is constructed of a metal material having a significant heat diffusion capacity sufficient to achieve liquid-like deformation in an atmospheric environment of -15°C to 40°C.
2. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 1, characterized in that: The metal material having a significant thermal diffusion capacity sufficient to achieve liquid-like deformation is obtained by amorphizing the metal.
3. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 1, characterized in that: The metal material having a significant thermal diffusion capacity sufficient to achieve liquid-like deformation is formed into an amorphous metal layer (1), and the atomic arrangement in the amorphous metal layer (1) is in a disordered state.
4. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 2, characterized in that: The method for realizing metal amorphization comprises: obtaining an amorphous metal layer (1) by mechanically pressing a metal material.
5. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 3 or 4, characterized in that: The raw material of the amorphous metal layer (1) includes metal.
6. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 3 or 4, characterized in that: The raw material of the amorphous metal layer (1) is silver and / or gold.
7. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 3 or 4, characterized in that: include: The amorphous metal layer (1) is transferred to the surface of the object to be lubricated (3).
8. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 1, characterized in that: The material of the object to be lubricated (3) is metal or non-metal.
9. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 4, characterized in that: The pressed metal material is obtained by drying a metal dispersion, or by metal sputtering, metal deposition or metal evaporation.
10. The method for realizing solid interface lubrication based on metal surface diffusion according to claim 1, characterized in that: The metal material having a significant heat diffusion capacity sufficient to achieve liquid-like deformation is constructed on at least a portion of the surface of the object to be lubricated (3) by direct epitaxial growth, chemical wet growth or nanoparticle superlattice self-assembly.