Self-adaptive antifriction WS2-DLC / DLC multilayer coating as well as preparation method and application thereof

Abstract

The invention relates to the technical field of material surface modification, in particular to a self-adaptive antifriction WS2-DLC / DLC multi-layer coating and a preparation method and application thereof.The preparation method comprises the following steps that a middle Cr layer is deposited on the surface of a substrate, a WS2-DLC composite layer is deposited on the middle Cr layer, a DLC layer is deposited on the WS2-DLC composite layer through direct current magnetron sputtering, and the self-adaptive antifriction WS2-DLC / DLC multi-layer coating is obtained. According to the self-adaptive antifriction WS2-DLC / DLC multilayer coating and the preparation method thereof, the self-adaptive antifriction WS2-DLC / DLC multilayer coating is obtained by alternately depositing the WS2-DLC composite layer and the DLC layer for multiple times, and the self-adaptive antifriction WS2-DLC / DLC multilayer coating has the advantages of being excellent in wide temperature range performance, high in binding force, flexible and controllable in structure and the like, an efficient, reliable and economical solution is provided for surface protection of mechanical parts, and the self-adaptive antifriction WS2-DLC / DLC multilayer coating is suitable for industrial production. The performance and the service life of mechanical parts under complex working conditions are remarkably improved, and the requirements of industrial production for high precision, high reliability and long service life of mechanical equipment are met.

Description

Technical Field

[0001] The present invention relates to the technical field of material surface modification, and particularly relates to an adaptive friction-reducing WS 2 -DLC / DLC multi-layer coating, its preparation method and application. Background Art

[0002] In the modern industrial field, the efficient and stable operation of mechanical equipment is crucial for production activities. However, during the operation of mechanical equipment, the friction and wear problems on the surfaces of components seriously affect their service life and performance, which has become one of the key challenges faced by the entire field of mechanical engineering. According to statistics, 1 / 3 - 1 / 2 of the world's energy is consumed by friction, and approximately more than 50% of all failed mechanical parts are due to wear. For example, in the automotive industry, friction between moving parts leads to energy loss and reduced fuel efficiency, and about 10% of automotive energy consumption is caused by friction and wear phenomena. Therefore, reducing the friction and wear on the surfaces of friction pairs of mechanical equipment, improving mechanical efficiency, and extending the service life of equipment are of extremely important significance.

[0003] Traditional lubrication methods mainly rely on gas, liquid, and solid lubricants. Gas or liquid lubricants are very sensitive to temperature. For example, the operating temperature of grease-based lubricating materials cannot exceed 200°C, and that of polymer-based lubricating materials cannot exceed 400°C. They will reduce their performance due to oxidation or chemical reactions in high-temperature environments and cannot meet the lubrication and friction reduction requirements of some mechanical equipment components (such as bearings, gears, pistons, etc.) in a wide temperature range. At the same time, they will also bring environmental pollution problems. And traditional lubricating coatings often show a decline in performance in high-temperature or low-temperature environments. For example, some liquid lubricants are prone to volatilization, oxidation, or decomposition at high temperatures, resulting in the loss of lubrication effect; while solid lubricants such as WS 2 、MoS 2 etc., although they can provide lubrication to a certain extent, they will also undergo oxidation or structural changes at high temperatures, thus affecting their lubrication performance. In addition, coatings with a single component often have difficulty meeting actual requirements in terms of comprehensive performance. For example, some high-hardness coatings, although having good wear resistance, may lack sufficient lubricity, resulting in large frictional forces and wear during friction.

[0004] With the successful application of hard coatings in the cutting field, surface coating technology has shown great potential in the field of tribology and has become an effective way to solve the wear problems of mechanical equipment components. By preparing solid coatings on the surfaces of components, it is possible to improve the surface load-bearing capacity of the substrate materials of the components while achieving wide-temperature-range lubrication and friction reduction without the need to stop the machine or disassemble the equipment. In recent years, the development and research of wide-temperature-range self-lubricating solid coatings have received extensive attention from domestic and foreign researchers, but it is still in its infancy and has not been widely applied in the field of mechanical equipment.

[0005] Due to its advantages such as high hardness, low friction coefficient, good chemical stability and biocompatibility, DLC coatings have been widely studied and applied in the fields of tool coatings, mechanical part protection, etc. However, the stability and lubrication performance of DLC coatings at high temperatures still need to be improved. To address this issue, researchers have attempted to modify DLC coatings by adding various elements or compounds. Sulfur-containing compounds such as WS 2 play an important role in the lubrication field, and their layered structure enables them to have good lubrication performance within a certain temperature range. However, when WS 2 coatings are used alone, there are some defects, such as weak adhesion to the substrate, easy peeling during friction, and poor oxidation resistance at high temperatures.

[0006] In terms of multi-layer coating structures, although multi-layer coatings have advantages over single-layer coatings in certain properties, such as improving the hardness, toughness and wear resistance of coatings through the synergistic effect between different layers, there is still a lack of effective methods and theoretical guidance on how to reasonably design the structure and composition of multi-layer coatings to achieve excellent lubrication and wear resistance over a wide temperature range. Summary of the Invention

[0007] Aiming at the deficiencies of the above-mentioned existing technologies, the purpose of the present invention is to provide an adaptive friction-reducing WS 2 -DLC / DLC multi-layer coating and its preparation method and application. The WS 2 -DLC / DLC multi-layer coating of the present invention has the advantages of excellent performance over a wide temperature range and flexible structure regulation, can effectively solve the problems existing in the prior art, provides an efficient, reliable and economical solution for the surface protection of mechanical components, significantly improves the performance and service life of mechanical components under complex working conditions, and meets the requirements of industrial production for high precision, high reliability and long life of mechanical equipment.

[0008] To solve the above technical problems, the present invention adopts the following technical solutions: A preparation method of an adaptive friction-reducing WS 2 -DLC / DLC multi-layer coating, comprising the following steps: Deposit an intermediate Cr layer on the surface of the substrate by radio frequency magnetron sputtering to ensure the adhesion between the coating and the substrate and prevent the coating from peeling off.

[0009] Deposit WS 2 above the intermediate Cr layer by radio frequency magnetron sputtering, and deposit DLC by direct current magnetron sputtering. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer as an adaptive friction-reducing WS 2- The core layer of the DLC / DLC multi-layer coating, in which WS is 2 uniformly dispersed in the DLC substrate, and the layered structure of WS 2 gives the coating good lubricity, while DLC provides support and protection for it, improving the overall strength and stability of the composite layer. On top of the WS 2 -DLC composite layer, a DLC barrier layer is deposited by DC magnetron sputtering to prevent the diffusion of S element.

[0010] Multiple WS 2 -DLC composite layers and DLC barrier layers are alternately deposited to obtain an adaptive friction-reducing WS 2 -DLC / DLC multi-layer coating. Through the design of the multi-layer structure, the stability of the coating in a wide temperature range can be further enhanced.

[0011] The adaptive friction-reducing WS 2 -DLC / DLC multi-layer coating prepared by the present invention, in terms of composition, combines WS with good lubrication performance 2 with DLC with high hardness and high stability. The layered structure of WS 2 can play a friction-reducing role during the friction process, effectively reducing the friction coefficient. At low temperatures, WS 2 can maintain the integrity of its crystal structure and lubrication performance, providing good initial lubrication effect for the coating, while DLC has excellent chemical stability and thermal stability, and can resist oxidation and thermal degradation in high-temperature environments, ensuring the overall stability of the coating. By combining the two, the coating can maintain good lubrication performance in a wide temperature range, overcoming the problem of the failure of traditional lubricants at extreme temperatures. Secondly, in terms of structure design, a multi-layer structure is adopted. The design of the multi-layer structure increases the bonding force between the coating and the substrate. During the deposition process, by precisely controlling the deposition process parameters of each layer, precise control of the tissue structure and composition of each layer of the coating is achieved, so that a tight chemical bonding and good physical inlay structure are formed between the WS 2 -DLC layer and the DLC layer and between the coating and the substrate. Compared with the single-layer coating, this multi-layer structure effectively reduces the peeling risk of the coating during use, improves the adhesion and durability of the coating. Through the reasonable design of the structure and composition of the multi-layer coating of the present invention, excellent lubrication performance and wear resistance in a wide temperature range are achieved.

[0012] In the preferred embodiment of the present invention, the conditions for depositing the WS 2 -DLC composite layer are: the target-substrate distance is 50 mm to 450 mm, the sputtering pressure is 1.0 Pa to 2.0 Pa, the bias voltage is -10 V to -50 V, and the WS 2 sputtering power is 100 W to 150 W, and the DLC sputtering power is 100 W to 400 W.

[0013] Further preferably, WS 2 The sputtering power is 150 W, the DLC sputtering power is 400 W, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, and the deposition time is 0.5 hours.

[0014] In a preferred embodiment of the present invention, WS 2 -The deposition time of the DLC composite layer is 0.5 hours to 2 hours, and the thickness of the single-layer WS 2 -The DLC composite layer is 40 nm to 100 nm.

[0015] In a preferred embodiment of the present invention, the deposition conditions for the DLC barrier layer by DC magnetron sputtering are: the target-substrate distance is 50 mm to 450 mm, the sputtering pressure is 1.0 Pa to 2.0 Pa, the sputtering power is 50 W to 400 W, and the bias voltage is -10 V to -50V.

[0016] Further preferably, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, and the sputtering power is 300 W to 400 W.

[0017] In a preferred embodiment of the present invention, the deposition time of the DLC layer is 2 minutes to 20 minutes, and the thickness of the single-layer DLC layer is 1nm to 40 nm.

[0018] Further preferably, the RF power is 100 W, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the deposition time is 5 minutes, and the thickness is 1 nm to 10 nm.

[0019] In a preferred embodiment of the present invention, the deposition conditions for RF magnetron sputtering are: the deposition power is 50 W to 200 W, the bias voltage is -80 V, the duty cycle is 70%, and the gas flow rate is 50 sccm to 200 sccm.

[0020] In a preferred embodiment of the present invention, the deposition time for RF magnetron sputtering is 30 min to 60 min, and the thickness of the Cr intermediate layer is 100 nm to 300 nm.

[0021] In a preferred embodiment of the present invention, the substrate is single-crystalline silicon or an AISI H12 hot work die steel block, the Ra of the single-crystalline silicon is <1 nm, and the roughness of the AISI H12 hot work die steel block is 0.1 μm to 0.16 μm.

[0022] Another object of the present invention is to provide an adaptive anti-friction WS prepared by the preparation method described in any one of the above 2 -DLC / DLC multi-layer coating, the WS 2- The DLC / DLC multi-layer coating is composed of alternately stacked WS 2 - DLC composite layers and DLC layers.

[0023] The third object of the present invention is to provide an application of the above-mentioned self-adaptive friction-reducing WS 2 - DLC / DLC multi-layer coating in mechanical equipment components.

[0024] Compared with the prior art, the beneficial effects of the present invention are: 1. First, an intermediate layer Cr layer is deposited on the substrate surface by radio frequency magnetron sputtering to ensure the bonding between the coating and the substrate and prevent the coating from peeling off. Then, WS 2 is deposited above the intermediate layer Cr layer by radio frequency magnetron sputtering, and DLC is deposited by direct current magnetron sputtering. WS 2 and DLC are deposited simultaneously to obtain a WS 2 - DLC composite layer, which serves as the core layer of the self-adaptive friction-reducing WS 2 - DLC / DLC multi-layer coating. A DLC barrier layer is deposited above the WS 2 - DLC composite layer by direct current magnetron sputtering to prevent the diffusion of S elements; multiple alternating depositions of WS 2 - DLC composite layers and DLC barrier layers are carried out to obtain the self-adaptive friction-reducing WS 2 - DLC / DLC multi-layer coating. The self-adaptive friction-reducing WS 2 - DLC / DLC multi-layer coating prepared by the present invention, in terms of composition, combines WS 2 with good lubricating performance and DLC with high hardness and high stability. The layered structure of WS 2 can play a friction-reducing role during the friction process and effectively reduce the friction coefficient. At low temperatures, WS 2 can maintain the integrity of its crystal structure and lubricating performance, providing a good initial lubrication effect for the coating, while DLC has excellent chemical stability and thermal stability and can resist oxidation and thermal degradation in high-temperature environments, ensuring the overall stability of the coating. By compounding the two, the coating can maintain good lubricating performance in a wide temperature range, overcoming the problem of the failure of traditional lubricants at extreme temperatures. Secondly, in terms of structural design, a multi-layer structure is adopted. The design of the multi-layer structure increases the bonding force between the coating and the substrate. During the deposition process, by precisely controlling the deposition process parameters of each layer, precise control of the tissue structure and composition of each layer of the coating is achieved, making WS 2A tight chemical bonding and a good physical interlocking structure are formed between DLC layers and between the coating and the substrate. Compared with single-layer coatings, this multi-layer structure effectively reduces the spalling risk of the coating during use, improves the adhesion and durability of the coating. Through the reasonable design of the structure and composition of the multi-layer coating, the present invention achieves excellent lubrication performance and wear resistance in a wide temperature range.

[0025] 2. The present invention deposits WS 2 -DLC composite layers by adopting a composite process of DC magnetron sputtering and RF magnetron sputtering, fully combining the advantages of the two processes, promoting the uniform mixing and good combination of WS 2 and DLC. The DLC layer ensures the hardness and load-carrying capacity of the multi-layer coating, enabling the coating to maintain good lubrication performance in a wide temperature range and overcoming the problem of traditional lubricants failing at extreme temperatures.

[0026] 3. The multi-layer structure prepared by the present invention also endows the coating with adjustability, and the thickness and composition ratio of each layer can be flexibly adjusted according to different application scenarios and working conditions. For example, under high-temperature and high-load working conditions, the thickness and proportion of the DLC layer can be appropriately increased to enhance the load-carrying capacity and wear resistance of the coating; under working conditions with higher requirements for lubrication performance, the thickness of the WS 2 -DLC layer can be increased or its structure can be optimized to further improve the lubrication effect of the coating. This adjustability not only improves the adaptability of the coating but also reduces the production cost because there is no need to develop new coating materials for different working conditions, and only adjustments need to be made on the existing structure.

[0027] 4. The multi-layer structure design enables the coating to have excellent chemical stability and corrosion resistance while having good mechanical properties, and can effectively protect the substrate material in a complex working environment and extend its service life. Therefore, the WS 2 -DLC / DLC multi-layer coatings prepared by the present invention have broad application prospects in the fields of machining, automotive manufacturing, aerospace, etc. Description of the Drawings

[0028] Figure 1 is a scanning electron microscope image of the cross-sectional morphology of the WS 2 -DLC / DLC multi-layer coating prepared by the present invention.

[0029] Figure 2 is a comparison chart of the friction coefficients of the WS 2 -DLC / DLC multi-layer coating and the WS 2 coating prepared by the present invention at room temperature.

[0030] Figure 3 is the WS 2-DLC / DLC Multilayer Coating and WS 2 Friction Coefficient Comparison Diagram of the Coating at 400 °C High Temperature Specific Embodiment

[0031] The following combines the embodiments of the present invention and uses preferred embodiments and accompanying drawings for a detailed description. The technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0032] It should be noted that all the professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present invention. Unless otherwise specifically stated, various raw materials, reagents, instruments, and equipment used in the following embodiments of the present invention can be obtained through the market or prepared by existing methods.

[0033] Example 1 A preparation method of WS 2 -DLC / DLC multilayer coating for mechanical equipment parts, comprising the following steps: (1) Pretreat the substrate. Select single crystal silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100 °C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as bias voltage -400 V, duty cycle 70%, and cleaning time 20 min.

[0034] (2) Deposit the intermediate layer Cr on the surface of the single crystal silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum degree is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering is used, the sputtering power is 100 W, the bias voltage is set to -80 V, the duty cycle is 70%, the deposition time is 30 minutes, and the target-substrate distance is 60 mm.

[0035] (3) Deposit WS 2 above the intermediate layer Cr layer by radio frequency magnetron sputtering, and use direct current magnetron sputtering for DLC. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. Set the process parameters of the WS 2 -DLC composite layer. The background vacuum degree is 1.5×10 -4Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, and RF magnetron sputtering WS is used 2 , and DC magnetron sputtering DLC is used, WS 2 The sputtering power is 150 W, the DLC sputtering power is 400 W, the bias voltage and duty cycle are not set, the deposition time is 30 minutes, and the target-substrate distance is 420 mm.

[0036] (4)On the WS 2 -DLC composite layer, DC magnetron sputtering is used to deposit a DLC barrier layer, the process parameters of the DLC layer are set, the base vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, DC magnetron sputtering DLC is used, the sputtering power is 100 W, the bias voltage and duty cycle are not set, the deposition time is 5 minutes, and the target-substrate distance is 420 mm.

[0037] (5)Alternately sputter the WS 2 -DLC composite layer and DLC layer, the total deposition time is 6 hours, and a uniform, dense WS with good friction performance is obtained 2 -DLC / DLC multi-layer coating.

[0038] The multi-layer coating prepared in Example 1 is mainly composed of WS 2 -DLC and DLC, the thickness of the WS 2 -DLC composite layer is 50 nm, the thickness of the DLC layer is 5 nm, and the total thickness of the coating is 625 nm.

[0039] Example 2 A method for preparing a WS 2 -DLC / DLC multi-layer coating for mechanical equipment parts, comprising the following steps: (1)Pretreat the substrate. Select single crystal silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, and then dry it at 100 °C for 30 min. Then perform argon plasma cleaning, and the plasma cleaning parameters are set as bias voltage -400 V, duty cycle 70%, and cleaning time 20 min.

[0040] (2)Deposit an intermediate layer Cr on the surface of the single crystal silicon substrate by RF magnetron sputtering, set the process parameters of the intermediate Cr layer, the base vacuum is 1.5×10 -4Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering is used, the sputtering power is 100 W, the bias voltage is set to -80 V, the duty cycle is 70%, the deposition time is 30 minutes, and the sputtering pressure is 2.0 pa.

[0041] (3) Above the intermediate Cr layer, radio frequency magnetron sputtering of WS 2 , and direct current magnetron sputtering of DLC is used. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. The process parameters of the WS 2 -DLC composite layer are set. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the substrate is not heated, the substrate rotation speed is 15 r / min, radio frequency magnetron sputtering of WS 2 is used, and direct current magnetron sputtering of DLC is used. The sputtering power of WS 2 is 150 W, the sputtering power of DLC is 400 W, the bias voltage and duty cycle are not set, the deposition time is 30 minutes, and the sputtering pressure is 1.0 Pa.

[0042] (4) Above the WS 2 -DLC composite layer, a DLC barrier layer is deposited by direct current magnetron sputtering. The process parameters of the DLC layer are set. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering of DLC is used, the sputtering power is 100 W, the bias voltage and duty cycle are not set, the deposition time is 5 minutes, and the sputtering pressure is 1.0 pa; (5) Alternately sputter the WS 2 -DLC composite layer and the DLC layer. The total deposition time is 6 hours to obtain a uniform, dense WS 2 -DLC / DLC multi-layer coating with good friction performance.

[0043] The multi-layer coating prepared in Example 2 mainly consists of WS 2 -DLC and DLC. The thickness of the WS 2 -DLC composite layer is 30 nm, the thickness of the DLC layer is 1 nm, and the total thickness of the coating is 400 nm.

[0044] Example 3 A method for preparing a WS 2 -DLC / DLC multi-layer coating for mechanical equipment parts, comprising the following steps: (1) Pretreat the substrate. Select single-crystalline silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, and then dry it at 100 °C for 30 min. Then perform argon plasma cleaning. The plasma cleaning parameters are set as bias voltage -400 V, duty cycle 70%, and cleaning time 20 min.

[0045] (2) Deposit the intermediate layer Cr on the surface of the single-crystalline silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use DC magnetron sputtering, the sputtering power is 100 W, set the bias voltage to -80 V, the duty cycle is 70%, and the deposition time is 30 minutes. The gas flow rate is 200 sccm.

[0046] (3) Deposit WS 2 above the intermediate layer Cr layer by radio frequency magnetron sputtering, and deposit DLC by DC magnetron sputtering. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. Set the process parameters of the WS 2 -DLC composite layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use radio frequency magnetron sputtering for WS 2 and deposit DLC by DC magnetron sputtering. The sputtering power of WS 2 is 150 W, the sputtering power of DLC is 400 W, no bias voltage and duty cycle are set, the deposition time is 30 minutes, and the gas flow rate is 90 sccm; (4) Deposit a DLC barrier layer on the WS 2 -DLC composite layer by DC magnetron sputtering. Set the process parameters of the DLC layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use DC magnetron sputtering for DLC, the sputtering power is 100 W, no bias voltage and duty cycle are set, the deposition time is 5 minutes, and the gas flow rate is 90 sccm.

[0047] (5) Alternately sputter the WS 2 -DLC composite layer and the DLC layer, and the total deposition time is 6 hours to obtain a uniform, dense, and good friction performance WS 2 -DLC / DLC multi-layer coating.

[0048] The multi-layer coating prepared in Example 3 mainly consists of WS 2 -DLC and DLC. The thickness of the WS 2 -DLC composite layer is 40 nm, the thickness of the DLC layer is 4 nm, and the total thickness of the coating is 450 nm.

[0049] Example 4 A preparation method of a WS 2 -DLC / DLC multi-layer coating for mechanical equipment parts, comprising the following steps: (1) Pretreat the substrate. Select single crystal silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100 °C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as bias voltage -400 V, duty cycle 70%, and cleaning time 20 min; (2) Deposit the intermediate layer Cr on the surface of the single crystal silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use direct current magnetron sputtering, the sputtering power is 100 W, set the bias voltage to -80 V, the duty cycle is 70%, and the deposition time is 40 minutes.

[0050] (3) Deposit WS 2 above the intermediate layer Cr layer by radio frequency magnetron sputtering, and deposit DLC by direct current magnetron sputtering. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. Set the process parameters of the WS 2 -DLC composite layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use radio frequency magnetron sputtering for WS 2 and direct current magnetron sputtering for DLC. The sputtering power of WS 2 is 150 W, the sputtering power of DLC is 400 W, the bias voltage and duty cycle are not set, and the deposition time is 60 minutes.

[0051] (4) Deposit a DLC barrier layer on the WS 2 -DLC composite layer by direct current magnetron sputtering. Set the process parameters of the DLC layer. The background vacuum is 1.5×10 -4Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, DC magnetron sputtering DLC is used, the sputtering power is 100 W, the bias voltage and duty cycle are not set, and the deposition time is 5 minutes.

[0052] (5)Alternately sputter WS 2 -DLC composite layer and DLC layer, the total deposition time is 6 hours, and a uniform, dense WS with good friction performance is obtained 2 -DLC / DLC multi-layer coating.

[0053] The multi-layer coating prepared in Example 4 is mainly composed of WS 2 -DLC and DLC, the thickness of the WS 2 -DLC composite layer is 60 nm, the thickness of the DLC layer is 1 nm, and the total thickness of the coating is 800 nm.

[0054] Example 5 A method for preparing a WS 2 -DLC / DLC multi-layer coating for mechanical equipment parts, comprising the following steps: (1)Pretreat the substrate. Select single crystal silicon as the substrate. Put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100 °C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as bias voltage -400 V, duty cycle 70%, and cleaning time 20 min.

[0055] (2)Deposit the intermediate layer Cr on the surface of the single crystal silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, DC magnetron sputtering is used, the bias voltage is set to -80V, the duty cycle is 70%, the deposition time is 30 minutes, and the sputtering power is 150 W.

[0056] (3)Deposit WS on the upper layer of the intermediate layer Cr layer by radio frequency magnetron sputtering 2 , and use DC magnetron sputtering DLC. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. Set the process parameters of the WS 2 -DLC composite layer. The background vacuum is 1.5×10 -4Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, and RF magnetron sputtering is used for WS 2 , and DC magnetron sputtering is used for DLC, no bias voltage and duty ratio are set, the deposition time is 30 minutes, and the WS 2 sputtering power is 150 W, and the DLC sputtering power is 200 W; (4)On the WS 2 -DLC composite layer, DC magnetron sputtering is used to deposit a DLC barrier layer, the process parameters of the DLC layer are set, the base vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, and DC magnetron sputtering is used for DLC, no bias voltage and duty ratio are set, the deposition time is 5 minutes, and the sputtering power is 200 W.

[0057] (5)Alternately sputter the WS 2 -DLC composite layer and the DLC layer, the total deposition time is 6 hours, and a uniform, dense WS 2 -DLC / DLC multi-layer coating with good friction performance is obtained.

[0058] The multi-layer coating prepared in Example 5 is mainly composed of WS 2 -DLC and DLC, and is prepared by a specific deposition process. The WS 2 -DLC composite layer has a thickness of 40 nm, the DLC layer has a thickness of 1 nm, and the total thickness of the coating is 500 nm.

[0059] Example 6 A method for preparing a WS 2 -DLC / DLC multi-layer coating for mechanical equipment parts, comprising the following steps: (1)Pretreat the substrate. Select single crystal silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100°C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as bias voltage -400 V, duty ratio 70%, and cleaning time 20 min.

[0060] (2)Deposit an intermediate layer of Cr on the surface of the single crystal silicon substrate by RF magnetron sputtering. Set the process parameters of the intermediate Cr layer. The base vacuum is 1.5×10 -4Pa, the protective gas is argon, the gas flow rate is 100 sccm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering is used, the sputtering power is 50 W, the bias voltage is set to -80 V, the duty cycle is 98%, the deposition time is 30 minutes, and the target-substrate distance is 60 mm.

[0061] (3) Above the intermediate Cr layer, radio frequency magnetron sputtering of WS 2 is carried out, and direct current magnetron sputtering of DLC is used. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. The process parameters of the WS 2 -DLC composite layer are set. The background vacuum degree is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 1.5 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, radio frequency magnetron sputtering of WS 2 is carried out, and direct current magnetron sputtering of DLC is used. The sputtering power of WS 2 is 100 W, the sputtering power of DLC is 100 W, the bias voltage and the duty cycle are not set, the deposition time is 120 minutes, and the target-substrate distance is 50 mm.

[0062] (4) Above the WS 2 -DLC composite layer, a DLC barrier layer is deposited by direct current magnetron sputtering. The process parameters of the DLC layer are set. The background vacuum degree is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 1.5 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering of DLC is used, the sputtering power is 50 W, the bias voltage and the duty cycle are not set, the deposition time is 2 minutes, and the target-substrate distance is 450 mm.

[0063] (5) The WS 2 -DLC composite layer and the DLC layer are sputtered alternately, and the total deposition time is 6 hours to obtain a uniform, dense WS 2 -DLC / DLC multi-layer coating with good friction performance.

[0064] Example 7 A preparation method of a WS 2 -DLC / DLC multi-layer coating for mechanical equipment parts, comprising the following steps: (1) Pretreat the substrate. Select single-crystalline silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100 °C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as bias voltage -400 V, duty cycle 70%, and cleaning time 20 min.

[0065] (2) Deposit the intermediate layer Cr on the surface of the single-crystalline silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 200 sccm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use direct current magnetron sputtering, the sputtering power is 200 W, set the bias voltage to -80 V, the duty cycle is 80%, the deposition time is 30 minutes, and the target-substrate distance is 60 mm.

[0066] (3) Deposit WS 2 above the intermediate layer Cr layer by radio frequency magnetron sputtering, and use direct current magnetron sputtering to deposit DLC. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. Set the process parameters of the WS 2 -DLC composite layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 1.5 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use radio frequency magnetron sputtering to deposit WS 2 and use direct current magnetron sputtering to deposit DLC. The sputtering power of WS 2 is 120 W, the sputtering power of DLC is 300 W, the bias voltage and duty cycle are not set, the deposition time is 30 minutes, and the target-substrate distance is 450 mm.

[0067] (4) Deposit a DLC barrier layer on the WS 2 -DLC composite layer by direct current magnetron sputtering. Set the process parameters of the DLC layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the sputtering pressure is 1.5 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, use direct current magnetron sputtering to deposit DLC, the sputtering power is 400 W, the bias voltage and duty cycle are not set, the deposition time is 20 minutes, and the target-substrate distance is 50 mm.

[0068] (5) Alternately sputter the WS 2 -DLC composite layer and the DLC layer, with a total deposition time of 6 hours, to obtain a uniform, dense WS 2 -DLC / DLC multi-layer coating with good friction performance.

[0069] Comparative Example 1 A method for preparing a DLC coating, comprising the following steps: (1) Pretreat the substrate. Select single-crystalline silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100 °C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as a bias voltage of -400 V, a duty cycle of 70%, and a cleaning time of 20 min; (2) Deposit an intermediate layer of Cr on the surface of the single-crystalline silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering is used, the sputtering power is 100 W, the bias voltage is set to -80 V, the duty cycle is 70%, and the deposition time is 30 min.

[0070] (3) Deposit a DLC layer on the Cr intermediate layer. Set the process parameters of the DLC layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering of DLC is used, the sputtering power is 100 W, the bias voltage and duty cycle are not set, and the deposition time is 6 hours to obtain a DLC coating.

[0071] Comparative Example 2 A method for preparing a WS 2 -DLC coating, comprising the following steps: (1) Pretreat the substrate. Select single-crystalline silicon as the substrate, put the substrate into acetone and alcohol for ultrasonic cleaning for 30 min to remove surface oil stains and impurities, then dry it at 100 °C for 30 min, and then perform argon plasma cleaning. The plasma cleaning parameters are set as a bias voltage of -400 V, a duty cycle of 70%, and a cleaning time of 20 min; (2) Deposit an intermediate layer of Cr on the surface of the single-crystalline silicon substrate by radio frequency magnetron sputtering. Set the process parameters of the intermediate Cr layer. The background vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min, direct current magnetron sputtering is used, the sputtering power is 100 W, the bias voltage is set to -80 V, the duty cycle is 70%, and the deposition time is 30 minutes.

[0072] (3) Above the intermediate Cr layer, WS is deposited by radio frequency magnetron sputtering 2 , and DLC is deposited by direct current magnetron sputtering. WS 2 and DLC are deposited simultaneously to obtain a WS 2 -DLC composite layer. Set the process parameters of the WS 2 -DLC composite layer. The base vacuum is 1.5×10 -4 Pa, the protective gas is argon, the gas flow rate is 50 sccm, the target-substrate distance is 60 mm, the sputtering pressure is 2.0 Pa, the substrate is not heated, the substrate rotation speed is 15 r / min. WS is deposited by radio frequency magnetron sputtering 2 , and DLC is deposited by direct current magnetron sputtering. The sputtering power of WS 2 is 150 W, the sputtering power of DLC is 400 W, the bias voltage and duty ratio are not set, and the deposition time is 6 hours to obtain a WS 2 -DLC coating.

[0073] Performance Test and Characterization The cross-section of the prepared WS 2 -DLC / DLC multi-layer coating is characterized by a scanning electron microscope equipped with an X-ray energy spectrometer to characterize the coating thickness and structure. The characterized results are as follows: The cross-sectional morphology of the WS 2 -DLC / DLC multi-layer coating is as shown in Figure 1 , which consists of a thicker WS 2 -DLC composite coating and a thinner pure DLC coating, showing an obvious multi-layer alternating microstructure.

[0074] The WS 2 -DLC / DLC multi-layer coating and the pure WS 2 coating are tested for friction with a friction and wear tester. Figure 2 This is a comparison chart of the friction coefficients of the WS 2 -DLC / DLC multi-layer coating and the WS 2 coating prepared by the present invention at room temperature. Under the same test conditions (the counter ball is Si 3 N 4 , the load is 5 N, the sliding speed is 0.1 m / s, and the test time is 10 min), the average friction coefficient of the pure WS 2 coating is about 0.294, and after 400 s of sliding friction, the friction coefficient rises to above 0.4; in contrast, the average friction coefficient of the WS 2 -DLC / DLC multi-layer coating is only 0.192 and is very stable during the entire sliding process. Figure 3 This is the WS 2 -DLC / DLC multi-layer coating and the WS 2Comparison chart of the friction coefficients of the coatings at 400 °C. It can be seen that at a high temperature of 400 °C, pure WS 2 The average friction coefficient of the coating is about 0.683. For WS 2 -DLC / DLC multi-layer coatings, after sliding for 350 s, the friction coefficient decreases to 0.05. In summary, WS 2 -DLC / DLC multi-layer coatings can significantly improve the tribological properties of the specimens and reduce the friction coefficient.

[0075] Through the comparative analysis of the above examples and comparative examples, it is fully proved that the WS 2 -DLC / DLC multi-layer coating preparation method of the present invention can be effectively implemented under different process parameters, and the prepared coatings have significant advantages in adaptive friction reduction, can effectively solve related technical problems, and meet the actual application requirements.

[0076] It should be noted that when the present invention involves a numerical range, it should be understood that both endpoints of each numerical range and any value between the two endpoints can be selected. Since the adopted step methods are the same as those in the examples, in order to prevent repetition, the present invention describes the preferred embodiments. Although the preferred embodiments of the present invention have been described, those skilled in the art can make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted to include the preferred embodiments and all changes and modifications falling within the scope of the present invention.

[0077] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these changes and modifications.

Claims

1. A method for preparing an adaptive friction reducing WS2-DLC / DLC multilayer coating, characterized in that: The following steps are involved: An intermediate Cr layer is deposited on the substrate surface by radio frequency magnetron sputtering; WS2 is deposited on the middle Cr layer by radio frequency magnetron sputtering, and DLC is deposited by direct current magnetron sputtering. WS2 and DLC are deposited simultaneously to obtain a WS2-DLC composite layer, which serves as the core layer of the adaptive friction-reducing WS2-DLC / DLC multilayer coating. A DLC barrier layer is deposited on the WS2-DLC composite layer by direct current magnetron sputtering to prevent the diffusion of S elements. The WS2-DLC composite layer and the DLC barrier layer are alternately deposited multiple times to obtain an adaptive friction-reducing WS2-DLC / DLC multilayer coating.

2. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: The conditions for depositing the WS2-DLC composite layer are: target-substrate distance of 50 mm~450 mm, sputtering pressure of 1.0 Pa~2.0 Pa, WS2 sputtering power of 100 W~150 W, and DLC sputtering power of 100 W~400 W.

3. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: The deposition time of the WS2-DLC composite layer is 0.5 hours to 2 hours, and the thickness is 40 nm to 100 nm.

4. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: The deposition conditions of the DLC barrier layer deposited by DC magnetron sputtering are: target-substrate distance of 50 mm~450 mm, sputtering pressure of 1.0 Pa~2.0 Pa, and sputtering power of 50 W~400 W.

5. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: The DLC barrier layer deposition time is 2 minutes to 20 minutes, and the thickness is 1 nm to 40 nm.

6. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: When the intermediate Cr layer is deposited by RF magnetron sputtering: the sputtering rate is 50 W~200 W, and the gas flow rate is 50 sccm~200 sccm.

7. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: When the intermediate Cr layer is deposited by radio frequency magnetron sputtering, the deposition time is 30 min~60 min, and the thickness of the Cr intermediate layer is 100 nm~300 nm.

8. The method for preparing the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 1, characterized in that: The substrate is single crystal silicon or AISI H12 hot working die steel block.

9. An adaptive friction-reducing WS2-DLC / DLC multilayer coating obtained by the preparation method according to any one of claims 1 to 8, wherein the WS2-DLC / DLC multilayer coating consists of alternately stacked WS2-DLC composite layers and DLC barrier layers.

10. Use of the adaptive friction reducing WS2-DLC / DLC multilayer coating according to claim 9 in mechanical equipment parts.

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