A low-orbit space radiation resistant self-adapting molybdenum disulfide-based multilayer composite film and a preparation method thereof

Abstract

The application relates to the field of aerospace material solid lubricating materials, and particularly discloses a low-orbit space radiation resistant self-adaptive molybdenum disulfide-based multilayer composite film and a preparation method. The closed field non-equilibrium magnetron sputtering technology is adopted to deposit a bonding layer (Ti), a gradient transition layer (MoS2 / Ti), a functional layer (MoS2 / Ti), a transition layer (MoS2-Ti-C) and a functional layer (MoS2-C) on a metal material to form a multilayer composite lubricating film. The prepared lubricating film can reliably serve in a low-orbit space environment, can effectively reduce the mechanical wear of a space mechanical friction moving part, and can still maintain stable tribological properties under long-time radiation in the low-orbit space, and is particularly suitable for bearings, gears and other long-time moving parts of a new generation of low-orbit serving space vehicles.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of aerospace material solid lubricant material, and particularly relates to a low-orbit space radiation resistant self-adaptive molybdenum disulfide-based multilayer composite film and a preparation method. BACKGROUND

[0002] Large low-orbit constellation is a space system that has appeared in the last 10 years and gradually matured, and is composed of hundreds to tens of thousands of satellites running in space 300 km to 2000 km away from the ground.

[0003] Solid lubricant film is the key to guarantee the long-term reliable service of the moving parts of satellite structures in low-orbit environment. At present, there are various types of solid lubricants applied to satellite moving parts, among which sputtered MoS2 has a lamellar structure and has a very low friction coefficient in vacuum, and is the most widely used and most successful lubricating material for space precision sliding moving parts.

[0004] The main reason for the failure of sputtered molybdenum disulfide film in space environment is directly related to space radiation environment. Space radiation mainly includes space ultraviolet radiation, atomic oxygen erosion, high-energy particle radiation (electrons, protons), etc. With the continuous development of space exploration activities, in order to meet the long-term service requirements of space vehicles in low-orbit space, sputtered molybdenum disulfide film must meet the ability of low-orbit space radiation resistance. Research shows that a large number of vacancies in the MoS2 film agglomerate to form large-size cavities during irradiation, and the film is severely amorphized after irradiation damage greater than 5dpa. Irradiation hardening leads to a decrease in film toughness, and at the same time, the irregular transfer of disordered structure at the friction interface is worse than that of unirradiated samples, which leads to the rapid push-out of ordered transfer film from the contact surface during friction, and the wear resistance life is rapidly decreased by 1-2 orders of magnitude.

[0005] Therefore, improving the space radiation resistance of sputtered molybdenum disulfide film in low-orbit is the key to realize the application of this material system in low-orbit satellites.

[0006] CN 115323326 A discloses a long-life molybdenum disulfide-based composite film resistant to space atomic oxygen irradiation and its preparation method and application, belonging to the technical field of solid lubrication. The Ti layer can increase the bonding strength between the molybdenum disulfide-based composite film and the substrate. The Ti content in the MoS2-LaF3-Ti layer on the surface of the Ti layer is 6-10 at%, and the LaF3 content is 2-4 at%. Ti and LaF3 exist in the form of solid solution, greatly reducing the sensitivity of MoS2 to atomic oxygen, significantly improving the atomic oxygen irradiation resistance and wear life of the composite film, reducing the friction coefficient, and effectively solving the problem of rapid decline in wear life of the molybdenum disulfide film under the erosion of high-dose space atomic oxygen. However, the thickness of the MoS2-LaF3-Ti composite film in this technology is between 2-5 μm, which cannot meet the demand for sputtering molybdenum disulfide film with a thickness of 1 μm on space precision bearings, harmonic parts, etc. According to the adhesive wear characteristics of molybdenum disulfide, the film thickness is highly related to the film lubrication life. In addition, the MoS2-LaF3-Ti film in this invention is different from the composition in this invention. CN202311541172 discloses a wear-resistant molybdenum disulfide-based composite film and its preparation method. A molybdenum disulfide-based solid lubrication film is deposited on the surface of a 316L stainless steel substrate using a composite magnetron sputtering technology. By controlling the Ti content in the MoS2-Ti functional layer, Ti exists in the form of solid solution, greatly reducing the sensitivity of MoS2 to the environment and the friction coefficient without destroying the layered structure and lubrication properties of the MoS2 film, and significantly improving the wear life of the MoS2 composite film. The composite film includes a Ti metal ion implantation layer, a Ti metal transition layer, and a MoS2-Ti functional layer from the surface of the substrate outward. Patent CN20161103338 discloses a molybdenum disulfide-lead titanium alloy nanometer multilayer film and its preparation method. The film includes a Ti transition layer, a gradient transition layer of Ti and molybdenum disulfide, an alternating multilayer formed by alternating stacking of molybdenum disulfide and lead titanium alloy, and a molybdenum disulfide surface layer. The film has a larger dry friction coefficient in a vacuum environment, stably maintaining at 0.02-0.06. CN202010497699 discloses a preparation method for a sub-10-nanometer-level biomimetic structure molybdenum disulfide-carbon multilayer film. A high-power pulsed unbalanced magnetron sputtering method is used to prepare a molybdenum disulfide layer on a treated substrate part, and a high-pressure plasma immersion ion implantation technology is used to inject CH4 plasma with a purity of more than 99.99% into the molybdenum disulfide layer to form a carbon layer. The cycle is repeated for 40-80 cycles, and the thickness of each layer is controlled to be less than 10 nm. This scheme adopts a nanometer multilayer structure, which is not only complex in process, but also does not give specific limitations on core issues such as sublayer interface bonding. It can be predicted that the reproducibility is poor. SUMMARY

[0007] In order to solve the above problems, the present application aims to provide a low-orbit space radiation resistant self-adaptive molybdenum disulfide-based multilayer composite film and a preparation method.

[0008] In order to achieve the above-mentioned application purposes, the present application provides the following technical solutions:

[0009] The present application provides a low-orbit space radiation resistant self-adaptive molybdenum disulfide-based multilayer composite film, which comprises, in order from the base body, a deposited Ti bonding layer, a MoS2-Ti gradient transition layer, a MoS2-Ti functional layer, a MoS2-Ti-C transition layer, and a MoS2-C functional layer. The friction coefficient of the composite film of the deposited Ti bonding layer+MoS2-Ti gradient transition layer+MoS2-Ti functional layer+MoS2-Ti-C transition layer+MoS2-C functional layer is between 0.016 and 0.18, and is less than 0.2. The mechanism is that a heterojunction structure is formed between carbon and molybdenum disulfide during friction, thereby reducing the friction coefficient. Under the film layer structure, as the friction time increases, the lubricating film layer is worn and deepened, and the carbon adhered to the surface of the counterpart still forms a heterojunction structure with the underlying molybdenum disulfide at the friction interface, thereby always exhibiting a low friction coefficient. The MoS2-Ti gradient transition layer in the multilayer composite film of the present application is arranged on one side to reduce the thermal expansion coefficient between the metal and the molybdenum disulfide, and on the other side to enhance the hardness and toughness of the molybdenum disulfide film. If the MoS2-Ti gradient transition layer (Ti content: 0-40 at%) is replaced by a Ti metal transition layer (Ti content: 100 at%), the film base bonding force will be poor and the wear life will be short. If the multilayer composite film is arranged as a deposited Ti bonding layer+MoS2-Ti gradient transition layer+MoS2-Ti functional layer, the purpose of the present application cannot be achieved, and the friction coefficient of this structure is close to 0.2 and is greater than 0.2. If the film structure is designed as a deposited Ti bonding layer+MoS2-Ti-C transition layer+MoS2-C functional layer, the purpose of the present application still cannot be achieved, and the main performance is poor friction and wear life. For example, in Example 1 of the present application, the friction and wear life of the deposited Ti bonding layer+MoS2-Ti gradient transition layer+MoS2-Ti functional layer+MoS2-Ti-C transition layer+MoS2-C functional layer is 3.1x10 5 revolutions, while the friction and wear life of the deposited Ti bonding layer+MoS2-Ti-C transition layer+MoS2-C functional layer is 6x10 4 revolutions.

[0010] As an embodiment of the present application, the thickness of the film is 1-5 μm.

[0011] As an embodiment of the present application, the thickness of the Ti bonding layer is 100-500 nm.

[0012] As an embodiment of the present application, the thickness of the MoS2-Ti gradient transition layer is 100-1000 nm.

[0013] As an embodiment of the present application, the thickness of the MoS2-Ti functional layer is 200-2000 nm.

[0014] As an embodiment of the present application, the thickness of the MoS2-Ti-C transition layer is 50-500 nm.

[0015] As an embodiment of the present application, the thickness of the MoS2-C functional layer is 50-1000 nm. In practice, the thickness and number of layers of the composite film layer are determined according to specific requirements.

[0016] As an embodiment of the present application, the Ti content in the MoS2-Ti gradient transition layer is 0-40 at%.

[0017] As an embodiment of the present application, the Ti content in the MoS2-Ti functional layer ranges from 8% to 20%.

[0018] As an embodiment of the present application, the C content in the MoS2-Ti-C gradient transition layer is 10-50 at%, and the Ti content is 5-12 at%.

[0019] As an embodiment of the present application, the C content in the MoS2-C functional layer is 40-50 at%.

[0020] The present application also provides a preparation method of the self-adapting MoS2-based multilayer composite film resistant to low-orbit space irradiation according to the technical solutions described above, comprising the following steps:

[0021] S1. Plasma cleaning, laser cleaning or high-temperature drying cleaning of the metal part;

[0022] S2. Depositing a Ti bonding layer on the surface of the metal substrate by magnetron sputtering using a titanium target;

[0023] S3. Depositing a MoS2-Ti gradient transition layer by magnetron sputtering using a titanium target and a molybdenum disulfide target;

[0024] S4. Depositing a MoS2-Ti functional layer by magnetron sputtering using a titanium target and a molybdenum disulfide target;

[0025] S5. Depositing a MoS2-Ti-C gradient transition layer by magnetron sputtering using a titanium target, a molybdenum disulfide target and a graphite target;

[0026] S6, depositing a MoS2-C functional layer by using a molybdenum disulfide target and a graphite target magnetron sputtering.

[0027] In step S1, the plasma cleaning has three main purposes: a. removing the natural oxide skin and excess materials on the surface of the test piece; b. cleaning the surface of the target material; and c. activating the surface of the metal part to increase the active sites on the metal surface and the adhesion between the thin film and the substrate. From a technical point of view, laser cleaning and high-temperature drying cleaning can also be used. Compared with other technologies, the plasma cleaning process has a low temperature.

[0028] The process gas that can be used in the plasma cleaning also includes oxygen, argon, nitrogen, compressed air, carbon dioxide, hydrogen, carbon tetrafluoride, etc. As an embodiment of the present application, in step S1, the plasma cleaning is performed by introducing argon under a pressure of less than 1x10-3 Pa and using a linear ion source to clean the metal substrate.

[0029] As an embodiment of the present application, the power of the linear ion source power supply is 2-4 kW, and the cleaning time is 20-60 min.

[0030] As an embodiment of the present application, in steps S1-S6, the closed field unbalanced magnetron sputtering technology is used. In step S1, the bias voltage is 350-500 V. In step S2, the bias voltage is set to 70-110 V. In steps S3-S6, the bias voltage is set to 40-80 V, respectively.

[0031] As an embodiment of the present application, in step S2, the titanium target current is 0.5-5 A, and the deposition time is 10-60 min.

[0032] As an embodiment of the present application, in step S3, the titanium target current is constant in the range of 1 A-5 A, the molybdenum disulfide target current is linearly increased from 0.1 A to 4 A, and the deposition time is 10-60 min. The constant means that the current is constant at a certain value in the range of 1 A-5 A.

[0033] As an embodiment of the present application, in step S4, the titanium target current is constant in the range of 1 A-5 A, the molybdenum disulfide target current is constant in the range of 1 A-4 A, and the deposition time is 10-120 min.

[0034] As an embodiment of the present application, in step S5, the molybdenum disulfide target current is constant in the range of 1 A-4 A, the graphite target current is linearly increased from 0.1 A to 3 A, the titanium target current is reduced to 0 A, and the deposition time is 2-60 min.

[0035] As one embodiment of the present application, in step S6, the molybdenum disulfide target current is constant in the range of 1A-4A, the graphite target current is constant in the range of 0.8-3A, and the deposition time is 5-120 min.

[0036] As one embodiment of the present application, the Ar gas in the plasma cleaning is pure, ≥99.999%; the Ti target is pure, ≥99.6%, the molybdenum disulfide target is pure, ≥99.6%, and the graphite target is pure, ≥99.6%.

[0037] The present application also provides the application of the self-adapting molybdenum disulfide-based multilayer composite film in aerospace materials as a solid lubricant material.

[0038] Compared with the prior art, the present application has the following excellent effects:

[0039] 1) The present application uses closed field unbalanced magnetron sputtering technology to prepare a lubricating film on the surface of a metal substrate, which comprises a deposition bonding layer (Ti), a gradient transition layer (MoS2-Ti), a functional layer (MoS2-Ti), a transition layer (MoS2-Ti-C), and a functional layer (MoS2-C) in sequence.

[0040] 2) The present application precisely prepares the molybdenum disulfide-based multilayer composite film by controlling the target current, argon flow and other factors during the growth of the lubricating film through process parameter regulation.

[0041] 3) The addition of a proper amount of carbon elements in the molybdenum disulfide film can promote the evolution of the friction interface into a highly ordered heterogeneous contact interface during movement, and the non-integer contact of the heterogeneous contact interface can reduce the friction coefficient by an order of magnitude, thus providing good lubrication performance in a vacuum environment; on the other hand, the addition of carbon elements can improve the toughness of the composite film and reduce the hardening effect of long-term irradiation on the composite film.

[0042] 4) The prepared composite film has a friction and wear life of greater than 3.0x10 26 r 2 , a friction coefficient of less than 0.02 under vacuum environment after being subjected to a total atomic oxygen irradiation of 7.8x10 8 rad(Si) 5 , a total ultraviolet irradiation of 8000ESH, and an ionizing irradiation of 2x10 BRIEF DESCRIPTION OF DRAWINGS

[0043] Other features, objects and advantages of the present application will become more apparent from the following detailed description of non-limiting embodiments, made with reference to the accompanying drawings:

[0044] Figure 1 A schematic diagram of a sputtered molybdenum disulfide-based multilayer composite film structure resistant to low-orbit space irradiation. DETAILED DESCRIPTION

[0045] The application provides a self-adapting molybdenum disulfide-based multilayer composite film resistant to low-orbit space irradiation, which has a structure as shown in the figure. Figure 1 The film structure sequentially comprises a bonding layer (Ti), a gradient transition layer (MoS2-Ti), a functional layer (MoS2-Ti), a gradient transition layer (MoS2-Ti-C), and a functional layer (MoS2-C) from the base body in order of distance. The Ti bonding layer has a thickness of 100-500 nm; the MoS2-Ti gradient transition layer has a thickness of 100-1000 nm, and the Ti content is 0-40 at%; the MoS2-Ti functional layer has a thickness of 200-2000 nm; the MoS2-Ti-C transition layer has a thickness of 50-500 nm, the C content is 10-50 at%, and the Ti content is 5-12 at%; and the MoS2-C functional layer has a thickness of 50-1000 nm, and the C content is 40-50 at%. The thickness and number of layers of the composite film layer are determined according to specific requirements.

[0046] The preparation method of the self-adapting molybdenum disulfide-based multilayer composite film can comprise the following steps:

[0047] Step 1, plasma cleaning: clean the metal parts and put them into a vacuum furnace, when the air pressure in the vacuum furnace is lower than 1×10 -3 Pa, argon is introduced, and the metal substrate is cleaned by using a linear ion source, the linear ion source power is 2-4 kW, and the time is 20-60 min;

[0048] Step 2, bonding layer deposition: deposit a Ti bonding layer on the surface of the metal base body by using a titanium target and magnetron sputtering, preferably, the titanium target current is 0.5-5 A, and the time is 10-60 min;

[0049] Step 3, gradient transition layer deposition: deposit a gradient transition MoS2-Ti layer by using a titanium target and a molybdenum disulfide target and magnetron sputtering, the titanium target current is constant, the molybdenum disulfide target current is linearly increased from 0.4 A to 4 A, and the time is 10-60 min;

[0050] Step 4, functional layer deposition: deposit a functional MoS2-Ti layer by using a titanium target and a molybdenum disulfide target and magnetron sputtering, the titanium target current and the molybdenum disulfide target current are constant, and the time is 10-120 min;

[0051] Step 5, transition layer deposition: deposit a transition MoS2-Ti-C layer by using a titanium target, a molybdenum disulfide target, and a graphite target and magnetron sputtering, the molybdenum disulfide target current is constant, the graphite target current is linearly increased from 0.1 A to 3 A, the titanium target current is reduced to 0 A, and the time is 2-60 min.

[0052] Step 6, functional layer deposition: MoS2-C functional layer was deposited by magnetron sputtering using MoS2 target and graphite target respectively, the MoS2 target current and the graphite target current were constant, and the time was 5-120 min.

[0053] The application will be described in detail below with reference to the examples. The following examples will help those skilled in the art to further understand the application, but do not limit the application in any form. It should be pointed out that those skilled in the art can make several adjustments and improvements without departing from the concept of the application. These all belong to the protection scope of the application.

[0054] Example 1

[0055] The preparation method of the adaptive MoS2-based multilayer composite film of the embodiment comprises the following steps:

[0056] Step 1, plasma cleaning: the titanium alloy TC4 metal part was cleaned and put into a vacuum furnace. When the air pressure in the vacuum furnace was lower than 1x10 -3 Pa, argon was introduced, and the metal substrate was cleaned by linear ion source, the linear ion source power was 3kW, the time was 20min, and the bias voltage was 400V;

[0057] Step 2, deposition of bonding layer: a bonding Ti layer was deposited on the surface of the metal substrate by magnetron sputtering using a titanium target, the titanium target current was 3A, the time was 10min, and the bias voltage was 80V;

[0058] Step 3, deposition of gradient transition layer: a gradient transition MoS2-Ti layer was deposited by magnetron sputtering using a titanium target and a MoS2 target respectively, the titanium target current was constant at 3A, the MoS2 target current was linearly increased from 0.4A to 2A, the time was 10min, and the bias voltage was 70V;

[0059] Step 4, deposition of functional layer: a functional MoS2-Ti layer was deposited by magnetron sputtering using a titanium target and a MoS2 target respectively, the titanium target current was constant at 3A and the MoS2 target current was constant at 2A, the time was 40min, and the bias voltage was 70V;

[0060] Step 5, deposition of gradient transition layer: a transition MoS2-Ti-C layer was deposited by magnetron sputtering using a titanium target, a MoS2 target and a graphite target respectively, the MoS2 target current was constant, the graphite target current was linearly increased from 0.1A to 1A, the titanium target current was linearly decreased from 3A to 0A, the time was 2min, and the bias voltage was 70V;

[0061] Step 6, deposition of functional layer: MoS2-C functional layer was deposited by magnetron sputtering using MoS2 target and graphite target respectively, the MoS2 target current was constant at 2A, the graphite target current was constant at 1A, the time was 20min, and the bias voltage was 70V.

[0062] The lubricating film deposited in this embodiment is smooth and flat with a gray-black surface. The thickness of the lubricating film is 1±0.1 μm, wherein the thickness of the Ti bonding layer is 100±10 nm; the thickness of the MoS2-Ti gradient transition layer is about 150±15 nm; the thickness of the MoS2-Ti functional layer is 550±55 nm; the thickness of the MoS2-Ti-C transition layer is 50±5 nm, the C content is 12 at%, and the Ti content is 8 at%; and the thickness of the MoS2-C functional layer is 150±15 nm, the C content is 45 at%. According to GJB2502.9-2006 1600 "Spacecraft Thermal Control Coating Test Method Part 9: Atomic Oxygen Test", the total atomic oxygen irradiation amount on the ground simulation of 15 years of in-orbit flight is 7.8×10 26 2 ; after the total ultraviolet irradiation amount of 8000 ESH, according to GJB2502.5-2006 1600 "Spacecraft Thermal Control Coating Test Method Part 5: Vacuum Ultraviolet Irradiation Test", the friction and wear life in a vacuum environment is 3.1×10 5 r, and the friction coefficient is 0.018.

[0063] Embodiment 2

[0064] The preparation method of the adaptive MoS2-based multilayer composite film of this embodiment comprises the following steps:

[0065] Step 1, plasma cleaning: the titanium alloy TC4 metal part is cleaned and placed in a vacuum furnace. When the air pressure in the vacuum furnace is lower than 1×10 -3 Pa, argon is introduced, and the metal substrate is cleaned by using a linear ion source. The power of the linear ion source power supply is 3 kW, the time is 20 min, and the bias voltage is 400 V.

[0066] Step 2, bonding layer deposition: a Ti bonding layer is deposited on the surface of the metal substrate by magnetron sputtering using a titanium target. The titanium target current is 5 A, the time is 15 min, and the bias voltage is 80 V.

[0067] Step 3, gradient transition layer deposition: a gradient transition MoS2-Ti layer is deposited by magnetron sputtering using a titanium target and a molybdenum disulfide target. The titanium target current is constant at 2 A, the molybdenum disulfide target current is linearly increased from 0.4 A to 3 A, the time is 20 min, and the bias voltage is 70 V.

[0068] Step 4, functional layer deposition: a functional MoS2-Ti layer is deposited by magnetron sputtering using a titanium target and a molybdenum disulfide target. The titanium target current is constant at 2 A, the molybdenum disulfide target current is constant at 3 A, the time is 90 min, and the bias voltage is 70 V.

[0069] ​Step 5: Gradient transition layer deposition: The transition MoS2-Ti-C layer was deposited by magnetron sputtering using a titanium target, a molybdenum disulfide target, and a graphite target, respectively. The current of the molybdenum disulfide target was constant, the current of the graphite target was linearly increased from 0.1A to 1A, and the current of the titanium target was linearly decreased from 2A to 0A. The time was 15 minutes and the bias voltage was 70V.

[0070] Step 6, functional layer deposition: using a molybdenum disulfide target and a graphite target for magnetron sputtering deposition of a functional MoS2-C layer, respectively, the molybdenum disulfide target current is constant at 2A, the graphite target current is constant at 1A, the time is 30min, and the bias voltage is 70V.

[0071] The lubricating film deposited in this embodiment has a bright, smooth, gray-black surface. Three-dimensional optical profilometry tests revealed that the thickness of the lubricating film was 2±0.2μm. The Ti bonding layer was 150±15nm thick; the MoS2-Ti gradient transition layer was 150±15nm thick; the MoS2-Ti functional layer was 1400±140nm thick; the MoS2-Ti-C transition layer was 100±10nm thick, with a C content of 16at% and a Ti content of 15at%; and the MoS2-C functional layer was 200±20nm thick, with a C content of 46at%. According to GJB2502.9-2006 1600, "Test Methods for Spacecraft Thermal Control Coatings - Part 9: Atomic Oxygen Test," the total atomic oxygen exposure for 15 years of simulated ground-based on-orbit flight was 7.8×10 26 pcs / m 2 According to GJB2502.5-2006 1600 "Test Methods for Spacecraft Thermal Control Coatings Part 5: Vacuum Ultraviolet Irradiation Test", the total UV irradiation dose was 8000ESH, and a ball-on-disc friction and wear tester was used. According to GJB3032-97 "Specifications for Sputtered MoS2-Based Self-Lubricating Solid Films", the friction and wear life in a vacuum environment was 3.6×10 5 r, and the friction coefficient is 0.017.

[0072] Example 3

[0073] The method for preparing the adaptive molybdenum disulfide-based multilayer composite film of this embodiment comprises the following steps:

[0074] Step 1: Plasma cleaning: clean the titanium alloy TC4 metal parts and put them into the vacuum furnace. -3 When Pa, argon gas was introduced and the metal substrate was cleaned using a linear ion source with a power of 2.5 kW, a time of 30 min, and a bias voltage of 400 V;

[0075] Step 2, bonding layer deposition: using a titanium target to deposit a bonding Ti layer on the surface of the metal substrate by magnetron sputtering, the titanium target current is 3A, the time is 20min, and the bias voltage is 80V;

[0076] Step 3, gradient transition layer deposition: gradient transition MoS2-Ti layer was deposited by magnetron sputtering using titanium target and molybdenum disulfide target, titanium target current was 3A constant, molybdenum disulfide target current was linearly increased from 0.4A to 2A, time was 60min, bias voltage was 70V;

[0077] Step 4, functional layer deposition: functional MoS2-Ti layer was deposited by magnetron sputtering using titanium target and molybdenum disulfide target, titanium target current was 0.8A constant and molybdenum disulfide target current was 1.8A constant, time was 90min, bias voltage was 70V;

[0078] Step 5, transition layer deposition: transition MoS2-Ti-C layer was deposited by magnetron sputtering using titanium target, molybdenum disulfide target and graphite target, molybdenum disulfide target current was 2A constant, graphite target current was linearly increased from 0.1A to 2A, titanium target current was linearly decreased from 0.8A to 0A, time was 60min, bias voltage was 70V;

[0079] Step 6, functional layer deposition: functional MoS2-C layer was deposited by magnetron sputtering using molybdenum disulfide target and graphite target, molybdenum disulfide target current was 1.8A constant, graphite target current was 2A constant, time was 60min, bias voltage was 70V.

[0080] The lubricating film deposited in the embodiment is smooth and bright with gray-black color. The thickness of the lubricating film is 5±0.5μm, the thickness of the Ti bonding layer is 200±20nm, the thickness of the MoS2-Ti gradient transition layer is 600±60nm, the thickness of the MoS2-Ti functional layer is 2200±220nm, the thickness of the MoS2-Ti-C transition layer is 1100±110nm, the content of C is 30at%, the content of Ti is 6at%, the thickness of the MoS2-C functional layer is 900±90nm, and the content of C is 50at%. 26 Referring to GJB2502.9-2006 1600 "Spacecraft Thermal Control Coating Test Method Part 9: Atomic Oxygen Test", after ground simulation of 15 years of in-orbit atomic oxygen total irradiation of 7.8×10 2 Referring to GJB2502.5-2006 1600 "Spacecraft Thermal Control Coating Test Method Part 5: Vacuum Ultraviolet Irradiation Test", after ultraviolet total irradiation of 8000ESH, the friction and wear life in vacuum environment is 4.1×10 5 r according to GJB3032-97 "Molybdenum Disulfide Based Self-lubricating Solid Film Specification", and the friction coefficient is 0.016.

[0081] The specific embodiments of the present application are described above. It should be understood that the present application is not limited to the specific embodiments described above, and various modifications or changes can be made by those skilled in the art within the scope of the claims, which do not affect the essential content of the present application.

Claims

1. An adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation, the film structure comprising, in descending order from the substrate, a deposited Ti bonding layer, a MoS2-Ti gradient transition layer, a MoS2-Ti functional layer, a MoS2-Ti-C gradient transition layer, and a MoS2-C functional layer; The adaptive molybdenum disulfide-based multilayer composite film is prepared by a method comprising the following steps: S1. Perform plasma cleaning, laser cleaning or high temperature drying cleaning on metal parts; use closed field unbalanced magnetron sputtering technology, S2, using a titanium target to deposit a Ti bonding layer on the surface of the metal substrate by magnetron sputtering; S3. Deposition of a MoS2-Ti gradient transition layer by magnetron sputtering using a titanium target and a molybdenum disulfide target. The titanium target current is kept constant in the range of 1A to 5A, and the molybdenum disulfide target current is linearly increased from 0.1A to 4A. The deposition time is 10 to 60 minutes. S4, using titanium target and molybdenum disulfide target to deposit MoS2-Ti functional layer by magnetron sputtering; S5. Deposition of a MoS2-Ti-C gradient transition layer by magnetron sputtering using titanium, molybdenum disulfide, and graphite targets. The current of the molybdenum disulfide target was kept constant in the range of 1A to 4A, the current of the graphite target was linearly increased from 0.1A to 3A, and the current of the titanium target was reduced to 0A. The deposition time was 2 to 60 minutes. S6. Depositing a MoS2-C functional layer by magnetron sputtering using a molybdenum disulfide target and a graphite target.

2. The adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to claim 1, characterized in that: The thickness of the film is 1 to 5 μm.

3. The adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to claim 1, characterized in that: The thickness of the Ti bonding layer is 100 to 500 nm; and / or, the thickness of the MoS2-Ti gradient transition layer is 100 to 1000 nm; and / or, the thickness of the MoS2-Ti functional layer is 200 to 2000 nm; and / or, the thickness of the MoS2-Ti-C gradient transition layer is 50 to 500 nm; And / or, the thickness of the MoS2-C functional layer is 50 to 1000 nm.

4. The adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to claim 1, characterized in that: The Ti content in the MoS2-Ti gradient transition layer is 0 to 40 at%; and / or, the Ti content in the MoS2-Ti functional layer ranges from 8% to 20%; And / or, the MoS2-Ti-C gradient transition layer has a C content of 10 to 50 at%, and a Ti content of 5 to 12 at%; And / or, the C content in the MoS2-C functional layer is 40 to 50 at%.

5. The adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to claim 1, characterized in that: In step S1, the plasma cleaning is carried out at a pressure lower than 1×10 -3 Argon gas was introduced under the condition of Pa, and the metal substrate was cleaned using a linear ion source.

6. The adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to claim 5, characterized in that: The power of the linear ion source is 2-4 kW, and the cleaning time is 20-60 minutes.

7. The adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to claim 1, characterized in that: In step S2, the titanium target current is 0.5 to 5 A, and the deposition time is 10 to 60 min; and / or, in step S4, the titanium target current is constant within the range of 1A to 5A, the molybdenum disulfide target current is constant within the range of 1A to 4A, and the deposition time is 10 to 120 minutes; And / or, in step S6, the current of the molybdenum disulfide target is constant in the range of 1A to 4A, the current of the graphite target is constant in the range of 0.8 to 3A, and the deposition time is 5 to 120 minutes.

8. Use of the adaptive molybdenum disulfide-based multilayer composite film resistant to low-orbit space radiation according to any one of claims 1 to 7 as a solid lubricant for aerospace materials.

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