Strong neutron irradiation resistant nano multilayer composite lubricating film and preparation method thereof
By depositing a Ti transition layer and a high-entropy alloy/molybdenum disulfide nano-multilayer composite film on the surface of nuclear reactor components, the failure problem of lubricating grease under strong irradiation environment was solved, and long-term stable lubrication performance and mechanical strength under high temperature and high pressure were achieved.
Patent Information
- Application Number
- CN202511622317.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-07
- Publication Date
- 2026-02-06
AI Technical Summary
Traditional lubricating greases are prone to molecular chain breakage, oxidative degradation, and volatilization under the strong radiation environment of nuclear reactors, resulting in a decline in lubrication performance and affecting the stability and safety of mechanical parts. It is difficult for a single material to simultaneously achieve radiation resistance, wear resistance, and lubrication performance.
A nano-multilayer composite film consisting of an alternating Ti transition layer, AlCoCrFeNi high-entropy alloy, and MoS2 is deposited on the substrate surface using magnetron sputtering technology to form a nano-multilayer composite lubricating film, thereby enhancing radiation resistance and lubrication performance.
It maintains stable lubrication performance under strong neutron irradiation, improves the life and reliability of mechanical parts, has a low coefficient of friction and long wear life, and is suitable for nuclear reactor control mechanisms.
Smart Images
Figure CN121472779A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of composite material preparation, and particularly relates to a nano multi-layer composite lubricating film and a preparation method thereof. BACKGROUND
[0002] In the nuclear reactor control system, a large number of movable parts (such as valves, drive mechanisms, etc.) are operated for a long time under high temperature, high pressure and strong neutron irradiation environment. The normal operation of these parts depends on a reliable lubrication system, and the traditional lubricating grease (such as mineral oil, silicon-based oil, fluorocarbon grease, etc.) is prone to molecular chain rupture, oxidative degradation and volatilization under strong irradiation environment, resulting in a sharp decrease in lubricating performance, and further causing mechanical wear, jamming and even failure, which seriously threatens the safety and stability of the nuclear reactor. Under the action of neutron irradiation, free radicals are generated in the organic molecules in the lubricating grease under the bombardment of high-energy particles, chain decomposition reaction is induced, and the release of volatile products further aggravates the failure of the lubricating film. In addition, irradiation also causes changes in the viscosity of the lubricating grease, decomposition of additives and deposition of oxidation products, forming abrasive wear and accelerating the fatigue damage of mechanical parts.
[0003] In the prior art, the research on lubricating materials for extreme environments of nuclear reactors mainly focuses on the development of solid lubricants (such as molybdenum disulfide, graphite, etc.) and solid lubricating coatings. Molybdenum disulfide (MoS2) is widely used in high temperature or vacuum environments due to its layered structure and low friction coefficient, but its structural stability under strong irradiation conditions is still controversial. In addition, high-entropy alloys (HEAs) have excellent anti-irradiation performance and high-temperature stability. However, a single material cannot simultaneously satisfy the requirements of anti-irradiation, wear resistance and lubricating performance, and the interface bonding force, thermal expansion matching and irradiation stability of multi-layer composite structures still need to be further explored.
[0004] MoS2 film has good lubricating performance and is an ideal lubricating film material for movable parts, but its anti-irradiation performance needs to be improved. SUMMARY
[0005] Therefore, the present application aims to solve the problem of the anti-irradiation performance of MoS2 film and develop a long-term lubricating film material with excellent comprehensive mechanical properties for the surface of sliding parts in nuclear reactor systems. The present application aims to provide a solid lubricating film suitable for the surface of movable parts in nuclear reactor systems and a preparation method thereof, mainly for solving the lubrication problem of related movable parts in nuclear reactor systems under long-term high temperature, strong neutron radiation and other complex working conditions. It is mainly used for movable parts in strong irradiation environment of nuclear reactors.
[0006] The technical solution of the present application is: The application discloses a nano multi-layer composite lubricating film resistant to strong neutron irradiation, and a long-life nano multi-layer composite film in a strong neutron irradiation environment. The film layer deposited on the surface of the substrate comprises a Ti transition layer 2, a high-entropy alloy (AlCoCrFeNi) 3 and a nano multi-layer functional layer in which MoS2 layers 4 are alternately arranged in the inner layer, and the outermost layer of the film layer is the MoS2 layer 4. The application further discloses a preparation method of the nano multi-layer composite lubricating film resistant to strong neutron irradiation. (1) substrate treatment; (2) ion cleaning; (3) preparing a Ti transition layer 2 on the surface of the metal substrate; (4) preparing a high-entropy alloy (AlCoCrFeNi) on the surface of the Ti transition layer 2; (5) preparing a MoS2 layer on the high-entropy alloy (AlCoCrFeNi) layer; In step (1), before preparation, the metal substrate is first ground and polished, and then cleaned in acetone solution and alcohol solution and dried.
[0007] In step (2), the surface of the substrate is bombarded by using a sun-grade layer ion source under vacuum conditions, and the step comprises the following steps: the dried metal substrate is placed into a vacuum furnace cavity and vacuumized to below 5*10 -3 Pa, the vacuum furnace cavity is heated to 70-90 DEG C, the sun-grade layer ion source is started to bombard the surface of the substrate, the voltage of the sun-grade layer ion beam source is 1000-1200 V, argon is introduced into the vacuum furnace cavity, the vacuum degree of the cavity is 0.3-1 Pa, the substrate is applied with a voltage of-300 to-500 V, and the cleaning time is 20-30 min.
[0008] In step (3), the Ti transition layer is prepared by using a high-power magnetron sputtering technology, and the step comprises the following steps: argon is introduced into the vacuum furnace cavity, the gas pressure is 0.5-1 Pa, the Ti target is electrified, the voltage of the Ti target is 500-650 V, the average power of the target is 8-12 kW, the substrate bias voltage is-70 to-100 V, and the deposition time is 10-12 min.
[0009] In step (4), the high-entropy alloy (AlCoCrFeNi) layer is prepared by using a magnetron sputtering technology, and the step comprises the following steps: after the Ti transition layer is prepared, argon is introduced into the vacuum furnace cavity, the gas pressure is 0.5-1 Pa, the target power of the high-entropy alloy (AlCoCrFeNi) is 3-6 kW, the substrate bias voltage is-70 to-100 V, and the deposition time is 2-5 min.
[0010] In step (5), the MoS2 layer is prepared by using a magnetron sputtering technology, including: introducing argon into a vacuum furnace cavity, the gas pressure is 0.5-1 Pa, the Ti target is electrified, the Ti target voltage is 400-550 V, the target power is 1-3 kW, the MoS2 target voltage is 550-700 V, the target power is 2-4 kW, the substrate bias is-50--70 V, and the deposition time is 2-5 min.
[0011] Further, steps (4) and (5) are repeated, and the number of repetitions is 10-15 times. Beneficial effects The application discloses a bearing channel surface solid lubricating film for a nuclear reactor system and a preparation method thereof, and adopts a non-equilibrium magnetron sputtering technology to deposit a nano-multilayer composite solid lubricating film composed of a Ti transition layer and a high-entropy alloy / MoS2 nano-multilayer on a stainless steel, bearing steel or the like substrate. The nano-multilayer composite film can be reliably served for a long time in a strong radiation environment such as a nuclear reaction control mechanism, has strong bearing capacity and low friction coefficient, can greatly improve the service life of a control mechanism moving part exposed to a nuclear radiation environment, and improves the reliability. In addition, the preparation method has the characteristics of environmental protection, flexibility, good uniformity and compactness of film thickness, programmed control of the film layer preparation process, easy adjustment of the modulation period of the film layer, batch processing and the like, is easy to realize industrial production, and has good application prospect.
[0012] The high-entropy alloy (AlCoCrFeNi) and the MoS2 nano-multilayer composite film can maintain long-term stable lubricating performance in a strong neutron radiation environment, and have excellent mechanical strength and wear resistance. The high-entropy alloy has good anti-radiation potential due to the synergistic effect of multiple elements and high-entropy stability; and the MoS2 nano layer can provide low friction coefficient and self-lubricating properties. The combination of the two forms a nano-multilayer composite film, the interface synergistic effect improves the comprehensive performance of the material, thereby solving the lubricating failure problem of the nuclear reactor control mechanism in a strong radiation environment. The film thickness of the nano-multilayer composite film is 1000-1400 nm, the hardness is 3.5-5 GPa (the test method is GB / T 25898), and the film has an average friction coefficient of less than 0.15 and a wear life of more than 300,000 revolutions in a vacuum environment after being irradiated by a total dose of 1x10 13 (n / cm 2 ) neutrons. BRIEF DESCRIPTION OF DRAWINGS
[0013] In order to more clearly illustrate the technical solutions in the specific embodiments or the prior art of the present application, the drawings needed in the specific embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.
[0014] Figure 1 is a structural schematic diagram of a nanocomposite film prepared by the present application; Figure 2 is a friction curve diagram of a composite film prepared by the present application before and after neutron irradiation. DETAILED DESCRIPTION
[0015] The following examples are provided to better further understand the present application and are not limited to the best mode, and do not limit the content and scope of protection of the present application. Any person under the inspiration of the present application or the combination of the present application with other prior art features can obtain any product same or similar to the present application, which falls within the protection scope of the present application.
[0016] A method for preparing a nuclear radiation resistant nanomultilayer MoS2-based lubricating film, comprising the following steps: a) depositing a titanium (Ti) intermediate transition layer on the surface of a metal substrate; b) using a periodic layer structure, alternately depositing high-entropy alloy (AlCoCrFeNi) and molybdenum disulfide (MoS2) lubricating layers above the transition layer to form a nanomultilayer composite film.
[0017] The thickness of the titanium (Ti) transition layer is 0.3-0.5 μm; in each group of periodic layer structure, the thickness ratio of the high-entropy alloy layer to the MoS2 lubricating layer is (2:1)~(1:2), and the overall composite coating contains 10~15 groups or more periodic units.
[0018] In step a), the purity of the sputtering Ti target material is ≥99.9%, the working environment is an argon atmosphere (pressure 0.5~1 Pa), and the sputtering power is 8~12 kW.
[0019] In step b), the high-entropy alloy (AlCoCrFeNi) and molybdenum disulfide (MoS2) layers use a magnetron sputtering technology, the periodic layer structure is plated by alternately switching (AlCoCrFeNi) / MoS2 targets, the working environment is an argon atmosphere (pressure 0.5~1 Pa), the high-entropy alloy (AlCoCrFeNi) target sputtering power is 3~6 kW, and the MoS2 target sputtering power is 2~4 kW.
[0020] The metal substrate is first ground and polished, then cleaned in acetone solution and alcohol solution in sequence and dried, and finally the surface of the substrate is bombarded by a positive stage layer ion source under vacuum conditions to remove impurities.
[0021] The step of bombarding the surface of the substrate by the positive stage layer ion source under vacuum conditions comprises: placing the dried metal substrate into a vacuum furnace chamber and vacuumizing to 5×10 -3 Pa, heating the vacuum furnace chamber to 70-90℃, opening the positive stage layer ion source to bombard the surface of the substrate, the voltage of the positive stage layer ion beam source being 1000-1200 V, introducing argon into the vacuum furnace chamber, the vacuum degree of the chamber being 0.3-1 Pa, the substrate being applied with -500--1200 V, and the cleaning time being 20-30 min.
[0022] The preparation of the multilayer composite film is carried out in a vacuum furnace chamber, the vacuum furnace chamber is provided with a workpiece table, and the side of the vacuum furnace chamber is respectively provided with a magnetron sputtering Ti target, a magnetron sputtering high-entropy alloy (AlCoCrFeNi) target, a magnetron sputtering MoS2 target and an anode layer ion source; The prepared lubricating film, after being subjected to neutron irradiation and gamma ray irradiation, meets at least one of the following technical indexes when sliding with a counterpart material: i) friction coefficient <0.15; ii) wear life ≥3×10 5 r Embodiment As Figure 1 shown, a strong neutron irradiation resistant nano multilayer composite lubricating film, the long-life nano multilayer composite film in a strong neutron irradiation environment, comprises a substrate and a film layer deposited on the surface of the substrate; The film layer deposited on the surface of the substrate 1 comprises a Ti transition layer 2 in the inner layer, a high-entropy alloy (AlCoCrFeNi) 3 and a MoS2 layer 4 arranged alternately in the nano multilayer functional layer, and the outermost layer of the film layer is the MoS2 layer 4; This embodiment is to prepare a nano composite film on the surface of a 9Cr18 stainless steel substrate, and the specific steps are as follows: (1) Select a 9Cr18 stainless steel substrate, first polish the stainless steel substrate to make the surface roughness less than Ra0.8, then place it in an acetone solution for ultrasonic cleaning for 10 min, then clean it in an alcohol solution for 10 min, and then dry it in a drying oven at a temperature of 70℃ for 20 min; (2) Place the cleaned and dried substrate into a vacuum furnace chamber and fix it on a workpiece rack, then vacuumize the vacuum furnace chamber to a vacuum degree better than 1×10 -3 Pa, and heat the vacuum furnace chamber to 80℃; (3) Turn on the positive ion beam source to bombard the surface of the substrate to remove impurities, the positive ion beam source voltage is 1000 V, the argon gas is introduced into the vacuum furnace chamber, the chamber vacuum degree is 0.5 Pa, the substrate is applied with-500 V, and the cleaning time is 30 min; (4) The argon gas is introduced into the vacuum furnace chamber, the gas pressure is 0.8 Pa, the high-power pulsed magnetron sputtering is carried out by applying power to the high-power magnetron sputtering Ti target, the average power of the Ti target is 10 kW, the substrate bias is-100 V, the deposition time is 10 min, and the Ti target is turned off; (5) The argon gas flow remains unchanged, the high-entropy alloy (AlCoCrFeNi) target is turned on by magnetron sputtering, the target power is 5 kW, the substrate bias is-50 V, the deposition time is 3 min, and the high-entropy alloy target is turned off; (6) The argon gas flow remains unchanged, the MoS2 target and the Ti target are turned on by magnetron sputtering, the MoS2 target power is 4 kW, the Ti target power is 1.5 kW, the substrate bias is-50 V, the deposition time is 3 min, and the MoS2 target and the Ti target are turned off; (7) The steps 5 and 6 are repeated 10 times through the coating program control.
[0023] (8) Stop coating until the temperature of the vacuum furnace chamber is below 50℃, take out the substrate, and obtain the nano multi-layer film.
[0024] As shown in Figure 2 , the prepared composite multi-layer film is tested and characterized, the total thickness of the composite multi-layer film is 1.37μm, the hardness tested by nano indentation is 4.2 GPa, the film-substrate adhesion tested by nano scratch is 24 N, and the average friction coefficient of the film in a vacuum environment after neutron irradiation with a total dose of 1×10 13 (n / cm 2 ) is 0.09, and the wear life exceeds 300,000 revolutions.
[0025] Obviously, the above embodiments are only examples for clearly illustrating, but not limiting the embodiments. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the embodiments are not required to be exhausted, and the obvious changes or variations derived therefrom are still within the protection scope of the present application.
Claims
1. A nano-multilayer composite lubricating film resistant to strong neutron irradiation, characterized in that: The composite lubricating film includes a substrate and a film layer deposited on the surface of the substrate; The film deposited on the substrate surface includes a Ti transition layer and a nano-multilayer functional layer; The nano-multilayer functional layer is formed by alternating high-entropy alloy layers and molybdenum disulfide layers; The outermost layer of the film deposited on the substrate surface is a molybdenum disulfide layer.
2. A method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film, characterized in that... Includes the following steps: The first step is to pretreat the substrate surface; The second step is to prepare a Ti transition layer on the surface of the pretreated substrate; The third step is to prepare a high-entropy alloy layer on the surface of the prepared Ti transition layer; The fourth step is to prepare a molybdenum disulfide layer on the surface of the prepared high-entropy alloy layer; The fifth step is to prepare a high-entropy alloy layer on the surface of the prepared molybdenum disulfide layer; Repeat steps four and five to obtain a nano-multilayer composite lubricating film resistant to strong neutron irradiation.
3. The method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film according to claim 2, characterized in that: The method for pretreating the substrate surface in the first step includes: First, the substrate surface is ground and polished, then washed and dried in acetone and ethanol solutions in sequence, and finally bombarded.
4. The method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film according to claim 3, characterized in that: The bombardment is performed under vacuum conditions using an anode layer ion source to bombard the substrate surface. The specific steps are as follows: the dried substrate is placed into a vacuum furnace chamber and the vacuum is evacuated to 5 × 10⁻⁶. -3 Below Pa, heat the vacuum furnace cavity to 70~90℃, turn on the anode layer ion source to bombard the substrate surface, the anode layer ion beam source voltage is 1000~1200 V, argon gas is introduced into the vacuum furnace cavity, the vacuum degree of the cavity is 0.3~1 Pa, the substrate is subjected to -300~-500V, and the cleaning time is 20~30 min.
5. The method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film according to claim 2, characterized in that: In the second step, high-power magnetron sputtering technology is used to prepare the Ti transition layer. The specific method is as follows: Argon gas is introduced into the vacuum furnace chamber at a pressure of 0.5-1 Pa. The Ti target is energized with a voltage of 500-650 V, an average target power of 8-12 kW, a substrate bias voltage of -70 to -100 V, and a deposition time of 10-12 min.
6. The method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film according to claim 2, characterized in that: In the third step, magnetron sputtering technology is used to prepare the high-entropy alloy layer. The specific method is as follows: After the Ti transition layer is prepared, argon gas is introduced into the vacuum furnace chamber at a pressure of 0.5~1 Pa, the high-entropy alloy target power is 3~6 kW, the substrate bias voltage is -70~-100 V, and the deposition time is 2~5 min.
7. The method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film according to claim 2, characterized in that: In the fourth step, magnetron sputtering technology is used to prepare the molybdenum disulfide layer. The specific method is as follows: Argon gas is introduced into the vacuum furnace chamber at a pressure of 0.5~1 Pa. The MoS2 and Ti targets are energized with a voltage of 400~550V and a power of 1~3kW for the Ti target, and a voltage of 550~700V and a power of 2~4kW for the MoS2 target. The substrate bias voltage is -50~-70V, and the deposition time is 2~5 min.
8. The method for preparing a strong neutron irradiation resistant nano-multilayer composite lubricating film according to claim 2, characterized in that: Repeat steps four and five 10 to 15 times.