Silicon-doped diamond-like carbon composite lubricating coating and its preparation method and application

Abstract

The present invention discloses a silicon-doped diamond-like composite lubricating coating, a preparation method and application thereof, and belongs to the technical field of wear-resistant coatings. The silicon-doped diamond-like composite lubricating coating includes a SiC base layer and a Si-DLC functional layer, which are sequentially arranged on the surface of a substrate; wherein the SiC base layer has a columnar structure, and the thickness of the SiC base layer is 0.3μm to 0.4μm; the Si-DLC functional layer has a dense featureless structure, and the thickness of the Si-DLC functional layer is 2.0μm to 5.0μm. The coating can simultaneously have low friction, high hardness, high toughness, high wear resistance and crack resistance. The preparation method is simple and easy to operate, and has the characteristics of low deposition temperature, uniform film formation, good repeatability and wide practicality. The obtained coating can be used for both hard substrates and flexible substrates, greatly broadening the application range of diamond-like films.

Description

Technical Field

[0001] The present invention relates to the technical field of wear-resistant coatings, and in particular to a silicon-doped diamond-like composite lubricating coating and a preparation method and application thereof. Background Art

[0002] In many situations, material surfaces are susceptible to various damages such as scratches, abrasion, and erosion, necessitating the preparation of appropriate protective coatings. Diamond-like carbon (DLC) coatings are widely used in fields such as machinery, electronics, and medicine due to their low friction coefficient, high hardness, high wear resistance, and chemical inertness. However, conventional DLC coatings suffer from problems such as poor toughness and high internal stress, which can lead to easy peeling of the coating, especially when applied to flexible substrates, leading to fracture.

[0003] Therefore, it is of great significance to prepare high-performance DLC lubricating coatings with high hardness, high toughness, high wear resistance and crack resistance.

[0004] In view of this, the present invention is proposed. Summary of the Invention

[0005] The purpose of the present invention is to provide a silicon-doped diamond-like composite lubricating coating and a preparation method and application thereof.

[0006] The present invention can be implemented like this:

[0007] In a first aspect, the present invention provides a silicon-doped diamond-like composite lubricating coating, the silicon-doped diamond-like composite lubricating coating comprising a SiC primer layer and a Si-DLC functional layer sequentially disposed on a substrate surface;

[0008] The SiC base layer has a columnar structure, and the thickness of the SiC base layer is 0.3 μm to 0.4 μm; the Si-DLC functional layer has a dense featureless structure, and the thickness of the Si-DLC functional layer is 2.0 μm to 5.0 μm.

[0009] In an optional embodiment, in the SiC base layer, the mass percentage of Si is 25% to 35%, and the mass percentage of C is 65% to 75%.

[0010] In an optional embodiment, in the Si-DLC functional layer, the mass percentage of Si is 2% to 8%, and the mass percentage of DLC is 92% to 98%.

[0011] In an optional embodiment, the silicon-doped diamond-like composite lubricating coating has at least one of the following characteristics:

[0012] Feature 1: The hardness of the silicon-doped diamond-like carbon composite lubricating coating is H, and H ranges from 18 GPa to 25 GPa; preferably, H is 18.0 GPa to 24.6 GPa;

[0013] Feature 2: The equivalent elastic modulus of the silicon-doped diamond-like carbon composite lubricating coating is E*, H / E*≥0.1; preferably, H / E* is 0.102 to 0.106;

[0014] Feature 3: The elastic recovery coefficient of the silicon-doped diamond-like carbon composite lubricating coating is We, We ≥ 60%; preferably, We is 76.5% to 82.2%;

[0015] Feature 4: The silicon-doped diamond-like carbon composite lubricating coating is in a compressive stress state as a whole; preferably, the SiC base layer is in a tensile stress state, and the Si-DLC functional layer is in a compressive stress state;

[0016] Feature 5: The microstructure of silicon-doped diamond-like carbon composite lubricating coating is dense;

[0017] Feature 6: The friction coefficient of the silicon-doped diamond-like carbon composite lubricating coating in an atmospheric environment of 25°C is 0.07 to 0.08; preferably, the friction coefficient is 0.072 to 0.079;

[0018] Feature 7: The friction coefficient of the silicon-doped diamond-like carbon composite lubricating coating in an atmospheric environment at 450°C is 0.040 to 0.065; preferably, the friction coefficient is 0.040 to 0.063;

[0019] Feature 8: The wear rate of silicon-doped diamond-like composite lubricating coating in an atmospheric environment of 25°C does not exceed 10 -7 m 3 / N·m;

[0020] Feature 9: The wear rate of silicon-doped diamond-like composite lubricating coating in 450°C atmospheric environment does not exceed 10 -6 m 3 / N·m;

[0021] Feature 10: During the friction process, the silicon-doped diamond-like carbon composite lubricating coating forms a complete amorphous carbon transfer film in situ at the friction pair.

[0022] In a second aspect, the present invention provides a method for preparing a silicon-doped diamond-like carbon composite lubricating coating as described in any of the aforementioned embodiments, comprising the following steps: sequentially providing a SiC primer layer and a Si-DLC functional layer on a substrate surface.

[0023] In an optional embodiment, the SiC base layer is prepared by DC magnetron sputtering;

[0024] The preparation conditions of SiC bottom layer include: vacuum degree in the equipment chamber is better than 1.0×10 -3 Pa, 50sccm~80sccm of argon is introduced into the equipment, and the gas pressure is maintained at 0.2Pa~0.3Pa; the substrate bias is -50V~-100V, and the bias duty cycle is 50%~60%; the target current is 1.0A~2.0A, and the deposition time is 20min~30min.

[0025] In an optional embodiment, the target material is a graphite-silicon composite target, wherein the Si content accounts for 35 wt% to 45 wt%.

[0026] In an optional embodiment, the Si-DLC functional layer is prepared by using a high-power pulsed magnetron sputtering technology assisted by an anode ion source;

[0027] The preparation conditions of the Si-DLC functional layer include: the argon gas flow rate is 50sccm~80sccm, the gas pressure is 0.2Pa~0.3Pa; the substrate bias is -50V~-100V, and the bias duty cycle is 50%~60%; a C-Si composite target is used, the Si content is 5wt%~10wt%, the HiPIMS pulse power is 5.0kW~8.0kW, and the duty cycle is 1.0%~5.0%; the anode layer ion source power corresponding to the auxiliary ionization of the sputtering gas is 0.50kW~0.75kW, and the duty cycle is 50%~60%; the deposition time is 6h~10h.

[0028] In an optional embodiment, before preparing the SiC base layer, the substrate is also pre-treated.

[0029] In an optional embodiment, the pretreatment includes grinding and polishing the substrate, then performing ultrasonic cleaning, and then placing the obtained substrate on a turntable in a vacuum chamber and performing plasma glow cleaning using an anode layer ion source.

[0030] In an optional embodiment, the ultrasonic cleaning time is 40 min to 50 min.

[0031] In an optional embodiment, plasma glow cleaning includes: placing the substrate into a vacuum chamber, evacuating the chamber to a vacuum better than 1.0×10 -3 Pa, then introduce 100 sccm to 150 sccm argon, and adjust the gas pressure to 0.36 Pa to 0.52 Pa; at the same time, adjust the substrate bias to -1000 V to -1200 V, and the bias duty cycle to 50% to 60%; then turn on the anode layer ion source, the anode layer ion source power is 0.8 kW to 1.0 kW, the duty cycle is 50% to 60%, and the plasma glow cleaning time is 30 min to 40 min.

[0032] In a third aspect, the present invention provides an application of a silicon-doped diamond-like composite lubricating coating according to any of the aforementioned embodiments. For example, the silicon-doped diamond-like composite lubricating coating can be used to be disposed on a hard substrate or a flexible substrate in the mechanical, electronic, or medical fields.

[0033] In alternative embodiments, the hard substrate comprises stainless steel or cemented carbide.

[0034] In alternative embodiments, the flexible substrate comprises a polymer, a metal foil, flexible thin glass, or a textile.

[0035] The beneficial effects of the present invention include:

[0036] The present invention achieves a silicon-doped diamond-like composite lubricating coating by applying a SiC primer layer and a Si-DLC functional layer of specific thickness and structure to the substrate surface. This coating exhibits low friction, high hardness, high toughness, high wear resistance, and crack resistance. The preparation method for this silicon-doped diamond-like composite lubricating coating is simple and easy to operate, and features low deposition temperature, uniform film formation, good reproducibility, and wide applicability. The resulting coating can be applied to both hard and flexible substrates, significantly expanding the application range of diamond-like films. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 This is a scanning electron microscope photograph of the cross section of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating prepared in Example 1;

[0039] Figure 2 This is a load-displacement curve of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating prepared in Example 1;

[0040] Figure 3 Actual photos of the high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating prepared in Example 1 after bending tests at different angles and corresponding optical morphology photos of the crease surface;

[0041] Figure 4 The friction coefficient curves of the high-strength, toughness, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating prepared in Example 1 at room temperature (25°C) and 450°C high temperature atmosphere. DETAILED DESCRIPTION

[0042] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer are used. Where the manufacturer of the reagents or instruments is not specified, all are conventional products that can be purchased commercially.

[0043] The silicon-doped diamond-like composite lubricating coating provided by the present invention and its preparation method and application are described in detail below.

[0044] The invention provides a silicon-doped diamond-like composite lubricating coating. The silicon-doped diamond-like composite lubricating coating comprises a SiC primer layer and a Si-DLC functional layer which are sequentially arranged on the surface of a substrate.

[0045] The SiC base layer has a columnar structure, which can be clearly observed.

[0046] In an optional embodiment, in the SiC base layer, the mass percentage of Si is 25% to 35% (such as 25%, 28%, 30%, 32% or 35%, etc.), and the mass percentage of C is 65% to 75% (such as 65%, 68%, 70%, 72% or 75%, etc.).

[0047] The thickness of the SiC base layer may be 0.3 μm to 0.4 μm, such as 0.3 μm, 0.35 μm or 0.4 μm, or other values ​​within the range of 0.3 μm to 0.4 μm.

[0048] If the SiC primer layer is too thin, it is not conducive to forming good adhesion between the Si-DLC functional layer and the SiC primer layer; if the SiC primer layer is too thick, it is not conducive to the performance of the Si-DLC functional layer.

[0049] The Si-DLC functional layer has a dense featureless structure, where "dense" may be understood as having a porosity of no more than 1%.

[0050] In an optional embodiment, in the Si-DLC functional layer, the mass percentage of Si is 2% to 8% (such as 2%, 3%, 4%, 5%, 6%, 7% or 8%, etc.), and the mass percentage of DLC is 92% to 98% (such as 92%, 93%, 94%, 95%, 96%, 97% or 98%, etc.).

[0051] The thickness of the Si-DLC functional layer may be 2.0 μm to 5.0 μm, such as 2.0 μm, 2.5 μm, 3.0 μm, 3.5 μm, 4.0 μm, 4.5 μm or 5.0 μm, or any other value within the range of 2.0 μm to 5.0 μm.

[0052] If the thickness of the Si-DLC functional layer is too thin, it is not conducive to the performance of the Si-DLC functional layer; if the thickness of the Si-DLC functional layer is too thick, it is not conducive to the use of the Si-DLC functional layer in certain specific application scenarios.

[0053] In some embodiments, the silicon-doped diamond-like composite lubricating coating has a hardness of H, which ranges from 18 GPa to 25 GPa. In some preferred embodiments, H is from 18.0 GPa to 24.6 GPa, such as 20.6 GPa, 21.3 GPa, 19.4 GPa, 18.4 GPa, 19.8 GPa, 19.4 GPa, 21.5 GPa, 23.3 GPa, 20.3 GPa, 24.1 GPa, 18.0 GPa, 24.6 GPa, 21.5 GPa, or 19.6 GPa, and may also be other values ​​within the range of 18.0 GPa to 24.6 GPa.

[0054] In some embodiments, the equivalent elastic modulus of the silicon-doped diamond-like carbon composite lubricating coating is E*, and H / E* is ≥ 0.1. In some preferred embodiments, H / E* is 0.102 to 0.106, such as 0.101, 0.102, 0.103, 0.104, 0.105, or 0.106, or other values ​​within the range of 0.102 to 0.106.

[0055] The above E*=E / (1-ν 2 ), where E is the elastic modulus and ν is the Poisson's ratio.

[0056] In some embodiments, the elastic recovery coefficient of the silicon-doped diamond-like carbon composite lubricating coating is We, where We ≥ 60%. In some preferred embodiments, We is 76.5% to 82.2%, such as 76.5%, 77.3%, 78.2%, 78.7%, 79.1%, 80.1%, 80.2%, 81.2%, or 82.2%, or other values ​​within the range of 76.5% to 82.2%.

[0057] In some embodiments, the silicon-doped diamond-like composite lubricating coating is generally compressive (σ < 0). The SiC base layer is in a tensile stress state, while the Si-DLC functional layer is in a compressive stress state. The silicon-doped diamond-like composite lubricating coating has a dense microstructure.

[0058] In some embodiments, the friction coefficient of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 25°C is 0.07-0.08. In some preferred embodiments, the friction coefficient of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 25°C is 0.072-0.079, such as 0.072, 0.073, 0.075, 0.076, 0.077, 0.078, or 0.079, or other values ​​within the range of 0.072-0.079.

[0059] In some embodiments, the friction coefficient of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 450° C. is 0.040 to 0.065. In some preferred embodiments, the friction coefficient of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 450° C. is 0.040 to 0.063, such as 0.040, 0.042, 0.047, 0.046, 0.049, 0.063, 0.058, or 0.041, or other values ​​within the range of 0.040 to 0.063.

[0060] In some embodiments, the wear rate of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 25°C is no more than 10 -7 m 3 / N·m. In some preferred embodiments, the wear rate of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 25°C is 2.06×10 -7 m 3 / N·m~3.47×10 -7 m 3 / N·m, such as 2.06×10 -7 m 3 / N·m, 2.14×10 - 7 m 3 / N·m, 2.18×10 -7 m 3 / N·m, 2.33×10 -7 m 3 / N·m, 2.45×10 -7 m 3 / N·m, 2.91×10 -7 m 3 / N·m、3.21×10 -7 m 3 / N·m、3.41×10 -7 m 3 / N·m、3.46×10 -7 m 3 / N·m or 3.47×10 -7 m 3 / N·m, etc., or 2.06×10-7 m 3 / N·m~3.47×10 -7 m 3 / Other values ​​within the range of N·m.

[0061] In some embodiments, the wear rate of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 450°C is no more than 10 -6 m 3 / N·m. In some preferred embodiments, the wear rate of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 450°C is 1.33×10 -6 m 3 / N·m~4.45×10 -6 m 3 / N·m, such as 1.33×10 -6 m 3 / N·m,1.61×10 -6 m 3 / N·m,1.85×10 -6 m 3 / N·m,2.51×10 -6 m 3 / N·m,2.94×10 -6 m 3 / N·m, 3.29×10 -6 m 3 / N·m,3.51×10 -6 m 3 / N·m, 3.67×10 -6 m 3 / N·m,4.11×10 -6 m 3 / N·m, 4.45×10 -6 m 3 / N·m, etc., or 1.33×10 -6 m 3 / N·m~4.45×10 -6 m 3 / Other values ​​within the range of N·m.

[0062] The silicon-doped diamond-like composite lubricating coating provided by the present invention can form a complete amorphous carbon transfer film in situ at the friction pair during the friction process.

[0063] As mentioned above, the silicon-doped diamond-like composite lubricating coating provided by the present invention can have better hardness, toughness, wear resistance and crack resistance than traditional DLC coatings. It has lower internal stress and higher toughness, and can effectively resist external wear and impact. Moreover, when the silicon-doped diamond-like composite lubricating coating is rubbed in a high-temperature atmospheric environment, the complete amorphous carbon transfer film formed in situ at the friction pair can effectively reduce the friction coefficient to, so that it has excellent lubrication and friction reduction effect at high temperatures.

[0064] Correspondingly, the present invention also provides a method for preparing the above-mentioned silicon-doped diamond-like carbon composite lubricating coating, comprising the following steps: sequentially arranging a SiC primer layer and a Si-DLC functional layer on the surface of a substrate.

[0065] In some embodiments, the SiC base layer is prepared by DC magnetron sputtering.

[0066] The preparation conditions of SiC bottom layer may include: vacuum degree in the equipment chamber is better than 1.0×10 -3 Pa, 50 sccm to 80 sccm (such as 50 sccm, 55 sccm, 60 sccm, 65 sccm, 70 sccm, 75 sccm or 80 sccm, etc.) of argon is introduced into the equipment, and the pressure is maintained at 0.2 Pa to 0.3 Pa (such as 0.2 Pa, 0.25 Pa or 0.3 Pa, etc.); the substrate bias voltage is -50 V to -100 V (such as -50 V, -55 V, -6 0V, -65V, -70V, -75V, -80V, -85V, -90V, -95V or -100V, etc.), the bias duty cycle is 50% to 60% (such as 50%, 55% or 60%, etc.), the target current is 1.0A to 2.0A (such as 1.0A, 1.5A or 2.0A, etc.), and the deposition time is 20min to 30min (such as 20min, 25min or 30min, etc.).

[0067] The target material used in the preparation process of the above-mentioned SiC base layer is a graphite-silicon composite target, wherein the Si content can be 35wt% to 45wt%, such as 35wt%, 36wt%, 37wt%, 38wt%, 39wt%, 40wt%, 41wt%, 42wt%, 43wt%, 44wt% or 45wt%, etc., or it can be other values ​​within the range of 35wt% to 45wt%.

[0068] In some embodiments, the Si-DLC functional layer is prepared by using a high-power pulsed magnetron sputtering technique assisted by an anode ion source.

[0069] Preparation conditions of the Si-DLC functional layer may include: an argon flow rate of 50 sccm to 80 sccm (such as 50 sccm, 55 sccm, 60 sccm, 65 sccm, 70 sccm, 75 sccm or 80 sccm, etc.), a gas pressure of 0.2 Pa to 0.3 Pa (such as 0.2 Pa, 0.25 Pa or 0.3 Pa, etc.); a substrate bias of -50 V to -100 V (such as -50 V, -55 V, -60 V, -65 V, -70 V, -75 V, -80 V, -85 V, -90 V, -95 V or -100 V, etc.), a bias duty cycle of 50% to 60% (such as 50%, 55% or 60%, etc.); a C-Si composite target is used, and the Si content accounts for 5 wt% to 10 wt% (such as 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%). % or 10wt%), the HiPIMS pulse power is 5.0kW to 8.0kW (such as 5.0kW, 5.5kW, 6.0kW, 6.5kW, 7.0kW, 7.5kW or 8.0kW, etc.), the duty cycle is 1.0% to 5.0% (such as 1.0%, 1.5%, 2.0%, 2.5%, 3.0%, 3.5%, 4.0%, 4.5% or 5.0%, etc.); the anode layer The anode layer ion source power corresponding to the ion source assisting ionization of the sputtering gas is 0.50kW~0.75kW (such as 0.50kW, 0.55kW, 0.60kW, 0.65kW, 0.70kW or 0.75kW, etc.), and the duty cycle is 50%~60% (such as 50%, 55% or 60%, etc.); the deposition time is 6h~10h (such as 6h, 7h, 8h, 9h or 10h, etc.).

[0070] Compared to existing industrial coating equipment, this high-power pulsed magnetron sputtering deposition technology, assisted by an anode layer ion source, boasts a significantly higher ionization rate. Furthermore, a separate ion source is used to increase the ionization rate of the sputtering gas. This coating system boasts higher bombardment energy, making it easier to produce composite lubricating coatings with specialized properties at lower temperatures (≤100°C). Furthermore, the equipment is simple to operate, facilitating large-scale industrial production.

[0071] For reference, the equipment used in the high-power pulsed magnetron sputtering deposition technology assisted by the anode layer ion source adopted in this application mainly includes a vacuum chamber, a turntable system, a high-power pulse power supply, a DC power supply, an anode layer ion source, an air intake unit and a molecular pump, wherein the anode layer ion source, the DC power supply and the high-power pulse power supply are evenly distributed on the inner wall of the vacuum chamber, and a turntable that can revolve and rotate is provided in the vacuum chamber. The high-power pulse power supply and the DC power supply are installed in parallel on the C-Si composite target, and the substrate is installed on the turntable. Regarding the equipment and deposition principles used for high-power pulsed magnetron sputtering and DC magnetron sputtering deposition assisted by the anode layer ion source, reference can be made to the relevant content of high-power pulsed magnetron sputtering and DC magnetron sputtering, and no excessive restrictions are made here.

[0072] In some embodiments, the method further includes pre-treating the substrate before preparing the SiC base layer.

[0073] The pretreatment includes grinding and polishing the substrate, then ultrasonic cleaning, and then placing the obtained substrate on a rotating rack in a vacuum chamber and performing plasma glow cleaning using an anode layer ion source.

[0074] Among them, ultrasonic cleaning refers to ultrasonic cleaning in alkaline detergent and deionized water. The ultrasonic cleaning time can be 40 minutes to 50 minutes, such as 40 minutes, 45 minutes or 50 minutes, etc., and can also be other values ​​within the range of 40 minutes to 50 minutes.

[0075] Plasma glow cleaning may include placing the substrate into a vacuum chamber and evacuating the chamber to a vacuum better than 1.0×10 -3 Pa, then introduce 100 sccm to 150 sccm (such as 100 sccm, 110 sccm, 120 sccm, 130 sccm, 140 sccm or 150 sccm, etc.) of argon, and adjust the gas pressure to 0.36 Pa to 0.52 Pa (such as 0.36 Pa, 0.42 Pa, 0.48 Pa or 0.52 Pa, etc.); at the same time, adjust the substrate bias voltage to -1000 V to -1200 V (such as -1000 V, -1050 V, -1100 V, -1150 V or -1200V, etc.), the bias duty cycle is 50% to 60% (such as 50%, 55% or 60%, etc.); then the anode layer ion source is turned on, the anode layer ion source power is 0.8kW to 1.0kW (such as 0.8kW, 0.85kW, 0.9kW, 0.95kW or 1.0kW, etc.), the duty cycle is 50% to 60% (such as 50%, 55% or 60%, etc.), and the plasma glow cleaning time is 30min to 40min (such as 30min, 35min or 40min, etc.).

[0076] As mentioned above, the silicon-doped diamond-like carbon composite lubricating coating provided by the present invention has silicon doping that significantly changes the microstructure and properties of the DLC coating, which can not only reduce its internal stress but also improve its wear resistance. The coating structure is designed to be a double-layer structure including a base layer with a columnar structure and a functional layer with a dense featureless structure, wherein the base layer is in a tensile stress state and the functional layer is in a compressive stress state. When the coating is bent, the stresses of the two will compensate each other, effectively preventing the coating from cracking. In the process of realizing this structural design, DC magnetron sputtering is used to deposit the base layer and advanced anode layer ion source assisted high-power pulsed magnetron sputtering equipment is used to deposit the functional layer. High-power pulsed magnetron sputtering technology can generate high-energy plasma and significantly increase the ionization rate of the sputtering gas through the assistance of the ion source, thereby enhancing the bombardment energy during the deposition process. This series of optimizations not only improves the quality of the film, but also brings significant improvements in its key properties such as toughness, wear resistance, and bonding strength. Compared with traditional magnetron sputtering equipment, high-power pulsed magnetron sputtering technology assisted by the anode layer ion source can prepare composite lubricating coatings with special properties at temperatures below 100°C.

[0077] Through the specific preparation method and preparation conditions provided by the present invention, a silicon-doped diamond-like composite lubricating coating with excellent hardness, toughness, wear resistance and crack resistance is effectively prepared.

[0078] In addition, the present invention also provides an application of the silicon-doped diamond-like composite lubricating coating. For example, the silicon-doped diamond-like composite lubricating coating can be used to be disposed on a hard substrate or a flexible substrate in the mechanical, electronic, or medical fields.

[0079] The rigid substrate may exemplarily but not limited to stainless steel or hard alloy, and the flexible substrate may exemplarily but not limited to polymer, metal foil, thin glass or textile.

[0080] It should be emphasized that by preparing the silicon-doped diamond-like composite lubricating coating provided by the present invention on the surface of a flexible substrate, cracking or breaking of the substrate in a bent state can be effectively avoided.

[0081] The highly tough and wear-resistant silicon-doped diamond-like composite lubricating coating provided by the present invention, as well as its preparation method and application are described in detail below.

[0082] Example 1

[0083] This embodiment provides a high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating, which is prepared by the following method:

[0084] S1: substrate pretreatment.

[0085] A 5mm thick 304 stainless steel sheet substrate was ultrasonically cleaned with alkaline detergent and deionized water for 45 minutes, and then the dried substrate was mounted on a rotating rack. The vacuum was then evacuated, and the background vacuum was better than 1.0×10 -3 Pa; introduce 100 sccm argon and adjust the gas pressure to 0.36 Pa; adjust the substrate bias to -1100 V and the duty cycle to 55%; turn on the anode layer ion source, set the power to 1.0 kW and the duty cycle to 55%, and perform glow cleaning on the substrate for 40 minutes.

[0086] S2: Preparing a SiC base layer on the substrate surface.

[0087] After glow cleaning, the argon flow rate was adjusted to 70 sccm, the gas pressure was maintained at 0.26 Pa, the substrate bias was -50 V, and the duty cycle was 55%; a C-Si composite target was used, and the Si content was 40 wt%; the DC power supply was turned on, the current was set to 1.0 A, and the deposition time was 20 min to form a SiC base layer.

[0088] S3: Preparing a Si-DLC functional layer on the surface of the SiC base layer.

[0089] After the SiC base layer deposition is complete, the argon flow rate is 50 sccm, the gas pressure is maintained at 0.20 Pa, the substrate bias is -50 V, and the duty cycle is 55%. The DC power supply is turned off, and the high-power pulsed magnetron sputtering power supply is turned on for deposition. A C-Si composite target with a Si content of 6wt% is used. The HiPIMS pulse power is 7.5kW and the duty cycle is 1.0%. At the same time, the anode layer ion source is turned on for auxiliary ionization. The anode layer ion source power is 0.60kW, the duty cycle is 55%, and the deposition time is 8 hours. The rotation speed of the rotor is stable at 2rpm throughout the deposition process, and the material is cooled naturally after preparation.

[0090] Figure 1 This is a scanning electron microscope image of a cross-section of the coating sample produced in this example. From bottom to top, it shows the 304 stainless steel substrate, the SiC base layer, and the Si-DLC functional layer. The image demonstrates the excellent growth of the Si-DLC functional layer on the SiC base layer. Furthermore, the Si-DLC functional layer exhibits a dense, featureless structure, while the SiC base layer exhibits a distinct columnar structure.

[0091] Testing revealed that the total thickness of the highly tough, wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this example was 2.63 μm, of which the SiC base layer was 0.37 μm thick and the Si-DLC functional layer was 2.26 μm thick. The SiC base layer contained 29.95% Si by mass and 70.05% C by mass. The Si-DLC functional layer contained 2.95% Si by mass and 97.05% DLC by mass.

[0092] Example 2

[0093] The difference between this embodiment and embodiment 1 is that the substrate of this embodiment is a YG6 cemented carbide sheet with a thickness of 5 mm.

[0094] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.66 μm, of which the thickness of the SiC base layer is 0.38 μm and the thickness of the Si-DLC functional layer is 2.28 μm.

[0095] Example 3

[0096] The difference between this embodiment and embodiment 1 is that the substrate of this embodiment is a flexible thin glass with a thickness of 0.1 mm.

[0097] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.50 μm, of which the thickness of the SiC base layer is 0.35 μm and the thickness of the Si-DLC functional layer is 2.15 μm.

[0098] Example 4

[0099] The difference between this embodiment and embodiment 1 is that the substrate of this embodiment is a metal aluminum foil with a thickness of 0.03 mm.

[0100] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.59 μm, of which the thickness of the SiC base layer is 0.34 μm and the thickness of the Si-DLC functional layer is 2.25 μm.

[0101] Example 5

[0102] The difference between this embodiment and embodiment 1 is that the substrate bias voltage during deposition of the Si-DLC functional layer in this embodiment is -80V.

[0103] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.48 μm, of which the thickness of the SiC base layer is 0.36 μm and the thickness of the Si-DLC functional layer is 2.12 μm.

[0104] Example 6

[0105] The difference between this embodiment and embodiment 1 is that the substrate bias voltage during the deposition of the Si-DLC functional layer in this embodiment is -100V.

[0106] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.42 μm, of which the thickness of the SiC base layer is 0.34 μm and the thickness of the Si-DLC functional layer is 2.08 μm.

[0107] Example 7

[0108] The difference between this embodiment and embodiment 1 is that in this embodiment, 50 sccm of argon gas is introduced during the deposition of the Si-DLC functional layer, and the gas pressure is adjusted to 0.20 Pa.

[0109] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.34 μm, of which the thickness of the SiC base layer is 0.32 μm and the thickness of the Si-DLC functional layer is 2.02 μm.

[0110] Example 8

[0111] The difference between this embodiment and embodiment 1 is that in this embodiment, 80 sccm of argon gas is introduced during the deposition of the Si-DLC functional layer, and the gas pressure is adjusted to 0.30 Pa.

[0112] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.91 μm, of which the thickness of the SiC base layer is 0.39 μm and the thickness of the Si-DLC functional layer is 2.52 μm.

[0113] Example 9

[0114] The difference between this embodiment and embodiment 1 is that the deposition time of the Si-DLC functional layer in this embodiment is 6 hours.

[0115] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.38 μm, of which the thickness of the SiC base layer is 0.37 μm and the thickness of the Si-DLC functional layer is 2.01 μm.

[0116] Example 10

[0117] The difference between this embodiment and embodiment 1 is that the deposition time of the Si-DLC functional layer in this embodiment is 10 hours.

[0118] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 4.86 μm, of which the thickness of the SiC base layer is 0.38 μm and the thickness of the Si-DLC functional layer is 4.48 μm.

[0119] Example 11

[0120] The difference between this embodiment and embodiment 1 is that the HiPIMS pulse power during the deposition of the Si-DLC functional layer in this embodiment is 5.0 kW.

[0121] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.41 μm, of which the thickness of the SiC base layer is 0.39 μm and the thickness of the Si-DLC functional layer is 2.02 μm.

[0122] Example 12

[0123] The difference between this embodiment and embodiment 1 is that the HiPIMS pulse power during the deposition of the Si-DLC functional layer in this embodiment is 8.0 kW.

[0124] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 3.06 μm, of which the thickness of the SiC base layer is 0.38 μm and the thickness of the Si-DLC functional layer is 2.68 μm.

[0125] Example 13

[0126] This embodiment is similar to the embodiment 1 except that the power of the anode layer ion source in this embodiment is 0.50 kW.

[0127] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 3.02 μm, of which the thickness of the SiC base layer is 0.40 μm and the thickness of the Si-DLC functional layer is 2.62 μm.

[0128] Example 14

[0129] The difference between this embodiment and embodiment 1 is that the power of the anode layer ion source in this embodiment is 0.75 kW.

[0130] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this embodiment is 2.56 μm, of which the thickness of the SiC base layer is 0.34 μm and the thickness of the Si-DLC functional layer is 2.22 μm.

[0131] Example 15

[0132] This embodiment provides a high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating, which is prepared by the following method:

[0133] S1: substrate pretreatment.

[0134] A 5mm thick 304 stainless steel sheet substrate was ultrasonically cleaned with alkaline detergent and deionized water for 40 minutes, and then the dried substrate was mounted on a rotating rack. The vacuum was then evacuated, and the background vacuum was better than 1.0×10 -3 Pa; introduce 120 sccm argon and adjust the gas pressure to 0.46 Pa; adjust the substrate bias to -1000 V and the duty cycle to 50%; turn on the anode layer ion source, set the power to 0.8 kW and the duty cycle to 50%, and perform glow cleaning on the substrate for 30 minutes.

[0135] S2: Preparing a SiC base layer on the substrate surface.

[0136] After glow cleaning, adjust the argon flow rate to 50sccm, maintain the gas pressure at 0.20Pa, the substrate bias to -75V, and the duty cycle to 50%; use a C-Si composite target with a Si content of 35wt%; turn on the DC power supply, set the current to 1.5A, and the deposition time to 25min to form a SiC base layer.

[0137] S3: Preparing a Si-DLC functional layer on the surface of the SiC base layer.

[0138] After the SiC base layer deposition is complete, the argon flow rate is 65sccm, the gas pressure is maintained at 0.25Pa, the substrate bias is -75V, and the duty cycle is 50%. The DC power supply is turned off, and the high-power pulsed magnetron sputtering power supply is turned on for deposition. A C-Si composite target with a Si content of 5wt% is used. The HiPIMS pulse power is 5.0kW and the duty cycle is 3.0%. At the same time, the anode layer ion source is turned on for auxiliary ionization. The anode layer ion source power is 0.50kW, the duty cycle is 50%, and the deposition time is 6 hours. The rotation speed of the rotor is stable at 2rpm throughout the deposition process, and the material is cooled naturally after preparation.

[0139] The total thickness of the silicon-doped diamond-like carbon composite lubricating coating obtained in this example was 2.35 μm, of which the SiC base layer was 0.31 μm thick and the Si-DLC functional layer was 2.04 μm thick. The SiC base layer contained 25.35% by mass of Si and 75.65% by mass of C. The Si-DLC functional layer contained 2.35% by mass of Si and 97.65% by mass of DLC.

[0140] Example 16

[0141] This embodiment provides a high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating, which is prepared by the following method:

[0142] S1: substrate pretreatment.

[0143] A 5mm thick 304 stainless steel sheet substrate was ultrasonically cleaned with alkaline detergent and deionized water for 50 minutes, and then the dried substrate was mounted on a rotating rack. The vacuum was then evacuated, and the background vacuum was better than 1.0×10 -3 Pa; introduce 150 sccm argon gas and adjust the gas pressure to 0.52 Pa; adjust the substrate bias to -1200 V and the duty cycle to 60%; turn on the anode layer ion source, set the power to 1.0 kW and the duty cycle to 60%, and perform glow cleaning on the substrate for 35 minutes.

[0144] S2: Preparing a SiC base layer on the substrate surface.

[0145] After glow cleaning, the argon flow rate was adjusted to 80 sccm, the gas pressure was maintained at 0.30 Pa, the substrate bias was -100 V, and the duty cycle was 60%; a C-Si composite target was used, and the Si content was 32 wt%; the DC power supply was turned on, the current was set to 2.0 A, and the deposition time was 30 min to form a SiC base layer.

[0146] S3: Preparing a Si-DLC functional layer on the surface of the SiC base layer.

[0147] After the SiC base layer deposition is complete, the argon flow rate is 80 sccm, the gas pressure is maintained at 0.30 Pa, the substrate bias is -100 V, and the duty cycle is 60%. The DC power supply is turned off, and the high-power pulsed magnetron sputtering power supply is turned on for deposition. A C-Si composite target with a Si content of 7wt% is used. The HiPIMS pulse power is 8.0kW and the duty cycle is 5.0%. At the same time, the anode layer ion source is turned on for auxiliary ionization. The anode layer ion source power is 0.75kW, the duty cycle is 60%, and the deposition time is 10 hours. The rotation speed of the rotor is stable at 2rpm throughout the deposition process, and the substrate is cooled naturally after preparation.

[0148] The total thickness of the silicon-doped diamond-like carbon composite lubricating coating obtained in this example was 4.91 μm, of which the SiC base layer was 0.39 μm thick and the Si-DLC functional layer was 4.52 μm thick. The SiC base layer contained 31.46% Si by mass and 68.54% C by mass. The Si-DLC functional layer contained 3.55% Si by mass and 96.45% DLC by mass.

[0149] Comparative Example 1

[0150] This comparative example differs from Example 1 in that the Si-DLC functional layer is deposited by DC magnetron sputtering. The DC magnetron sputtering conditions include: an argon flow rate of 50 sccm, a gas pressure maintained at 0.20 Pa, a substrate bias of -50 V, a duty cycle of 55%, a DC power supply for deposition, a C-Si composite target with a Si content of 6 wt%, a DC target current of 1.5 A, and a DC target voltage of 500 V. Simultaneously, an anode layer ion source is activated for auxiliary ionization, with an anode layer ion source power of 0.60 kW, a duty cycle of 55%, and a deposition time of 8 hours. The rotating frame speed is maintained at 2 rpm throughout the deposition process, and the material is cooled naturally after the preparation is completed.

[0151] The total thickness of the high-toughness and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.94 μm, of which the thickness of the SiC base layer is 0.38 μm and the thickness of the Si-DLC functional layer is 2.56 μm.

[0152] Comparative Example 2

[0153] The difference between this comparative example and Example 1 is that the Ar flow rate during the preparation of the Si-DLC functional layer is 150 sccm and the gas pressure is maintained at 0.6 Pa.

[0154] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.82 μm, of which the thickness of the SiC base layer is 0.43 μm and the thickness of the Si-DLC functional layer is 2.39 μm.

[0155] Comparative Example 3

[0156] The difference between this comparative example and Example 1 is that the substrate bias voltage during the preparation of the Si-DLC functional layer is 0V.

[0157] The total thickness of the high-toughness and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.72 μm, of which the thickness of the SiC base layer is 0.46 μm and the thickness of the Si-DLC functional layer is 2.26 μm.

[0158] Comparative Example 4

[0159] The difference between this comparative example and Example 1 is that the ion source power of the anode layer during the preparation of the Si-DLC functional layer is 0 W.

[0160] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.65 μm, wherein the thickness of the SiC base layer is 0.39 μm, and the thickness of the Si-DLC functional layer is 2.26 μm.

[0161] Comparative Example 5

[0162] The difference between this comparative example and Example 1 is that the power of the anode layer ion source during the preparation of the Si-DLC functional layer is 1.0 kW.

[0163] The total thickness of the high-toughness and wear-resistant silicon-doped diamond-like carbon composite lubricating coating of this comparative example is 1.92 μm, of which the thickness of the SiC base layer is 0.34 μm and the thickness of the Si-DLC functional layer is 1.58 μm.

[0164] Comparative Example 6

[0165] The difference between this comparative example and Example 1 is that no SiC base layer is deposited in this comparative example.

[0166] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.26 μm, wherein the thickness of the SiC primer layer is 0 μm, and the thickness of the Si-DLC functional layer is 2.26 μm.

[0167] Comparative Example 7

[0168] The difference between this comparative example and Example 1 is that the substrate of this comparative example is carbon steel.

[0169] The total thickness of the high-toughness and wear-resistant silicon-doped diamond-like carbon composite lubricating coating of this comparative example is 2.63 μm, of which the thickness of the SiC primer layer is 0.37 μm and the thickness of the Si-DLC functional layer is 2.26 μm.

[0170] Comparative Example 8

[0171] The difference between this comparative example and Example 1 is that an undoped DLC coating is prepared in this comparative example.

[0172] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.63 μm, wherein the thickness of the SiC base layer is 0.37 μm, and the thickness of the Si-DLC functional layer is 2.26 μm.

[0173] Comparative Example 9

[0174] The difference between this comparative example and Example 1 is that the tungsten-doped diamond-like carbon coating in this comparative example is prepared by the same process.

[0175] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.72 μm, wherein the thickness of the SiC base layer is 0.37 μm, and the thickness of the W-DLC functional layer is 2.35 μm.

[0176] Comparative Example 10

[0177] The difference between this comparative example and Example 1 is that the boron-doped diamond-like carbon coating in this comparative example is prepared by the same process.

[0178] The total thickness of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in this comparative example is 2.63 μm, of which the thickness of the SiC base layer is 0.37 μm and the thickness of the B-DLC functional layer is 2.26 μm.

[0179] Comparative Example 11

[0180] The difference between this comparative example and Example 1 is that the preparation parameter range of the SiC base layer is adjusted so that the thickness of the SiC base layer is 0.18 μm.

[0181] Comparative Example 12

[0182] The difference between this comparative example and Example 1 is that the preparation parameter range of the SiC base layer is adjusted so that the thickness of the SiC base layer is 0.50 μm.

[0183] Comparative Example 13

[0184] The difference between this comparative example and Example 1 is that the preparation parameter range of the Si-DLC functional layer is adjusted so that the thickness of the Si-DLC functional layer is 1.20 μm.

[0185] Comparative Example 12

[0186] The difference between this comparative example and Example 1 is that the preparation parameter range of the Si-DLC functional layer is adjusted so that the thickness of the Si-DLC functional layer is 6.0 μm.

[0187] Comparative Example 13

[0188] The difference between this comparative example and Example 1 is that the preparation parameter range of the SiC base layer is adjusted so that the mass percentage of Si in the SiC base layer is 20.05% and the mass percentage of C is 79.95%.

[0189] Comparative Example 14

[0190] The difference between this comparative example and Example 1 is that the preparation parameter range of the SiC base layer is adjusted so that the mass percentage of Si in the SiC base layer is 50.25% and the mass percentage of C is 49.75%.

[0191] Comparative Example 15

[0192] The difference between this comparative example and Example 1 is that the preparation parameter range of the Si-DLC functional layer is adjusted so that the mass percentage of Si in the Si-DLC functional layer is 1.20% and the mass percentage of DLC is 98.8%.

[0193] Comparative Example 16

[0194] The difference between this comparative example and Example 1 is that the preparation parameter range of the Si-DLC functional layer is adjusted so that the mass percentage of Si in the Si-DLC functional layer is 14.0% and the mass percentage of DLC is 86.0%.

[0195] Test example

[0196] ①. Structural testing was performed on the silicon-doped diamond-like composite lubricating coatings prepared in Examples 2 to 16. The results showed that the Si-DLC functional layers of the silicon-doped diamond-like composite lubricating coatings prepared in the above examples all had a dense featureless structure, and the SiC base layers all had a distinct columnar structure.

[0197] ②. A. The high-toughness and wear-resistant silicon-doped diamond-like composite lubricating coating prepared in Example 1 was partially tested for performance. The results are shown in Table 1 and Figure 2 shown. Figure 2 This is a load-displacement curve of the high-strength, tough, and wear-resistant silicon-doped diamond-like carbon composite lubricating coating obtained in Example 1, where Ee is the area between the loading curve and the unloading curve, representing the energy dissipated in the coating due to plastic deformation; Ep is the area under the unloading curve, representing the elastic energy of the deformation.

[0198] The hardness in Table 1 was measured according to GB / T 33051-2016 Determination of Thickness of Hardened Layer of Surface Hardened Films for Optical Functional Films; the equivalent elastic modulus E* was calculated according to the following formula: E* = E / (1-ν 2 ), where E refers to the elastic modulus and ν refers to the Poisson's ratio; the hardness modulus ratio data is rounded off; the elastic recovery coefficient is measured with reference to "GB / T 43602-2023 Physical Vapor Deposition Multilayer Hard Coatings - Composition, Structure and Performance Evaluation"; the internal stress is measured with reference to the laser curvature method and the Stony formula calculation method.

[0199] In addition, the same performance tests were performed on the coatings obtained in Examples 2 to 16 and Comparative Examples 1 to 16, and the results are also shown in Table 1.

[0200] B. The high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating obtained in Example 1 was subjected to bending tests at different angles at 30°, 60°, 90°, and 120°. The photos after the test and the optical morphology photos of the corresponding folds are shown in FIG. Figure 3 shown.

[0201] As can be seen from the figure, the silicon-doped diamond-like composite lubricating coating prepared on the 304 stainless steel substrate provided in Example 1 did not crack or peel off after bending and flattening tests at different angles of 0° (corresponding to column a), 30° (corresponding to column b), 60° (corresponding to column c), 90° (corresponding to column d), and 120° (corresponding to column e), and the coating has very excellent anti-cracking performance.

[0202] It should be noted that, taking column a as an example, a1 is the result of the object at the first viewing angle, a2 is the result of the object at the second viewing angle, and a3 is the optical morphology result of the surface of the object corresponding to the fold.

[0203] In the same manner, the silicon-doped diamond-like composite lubricating coatings prepared in Examples 2 to 16 did not crack or peel off after being bent and flattened at different angles of 30°, 60°, 90°, and 120°.

[0204] In the same manner, the silicon-doped diamond-like composite lubricating coatings prepared in Comparative Examples 1 to 16 also cracked and peeled off after bending and flattening tests at different angles of 30°, 60°, 90°, and 120°.

[0205] C. Friction tests were conducted on the high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating prepared in Example 1 and the Al2O3 friction pair at a room temperature of 25°C and a high temperature of 450°C. The friction time of the friction test at 25°C was 3600s, and the friction time of the friction test at 450°C was 900s. The results are shown in FIG. Figure 4 (a) and (b) and Table 2. In addition, the above experiments also show that after high temperature friction, the wear debris generated at the wear scar is transferred to the surface of the grinding ball to form a complete friction transfer film, resulting in its excellent lubrication and friction reduction effect.

[0206] Furthermore, the same performance tests were performed on the coatings obtained in Examples 2 to 16 and Comparative Examples 1 to 16, and the results are also shown in Table 2.

[0207] Table 1 Performance results

[0208]

[0209]

[0210] Table 2 Performance results

[0211]

[0212]

[0213] It can be seen from this that the high-toughness and wear-resistant silicon-doped diamond-like carbon composite lubricating coating provided by the embodiment of the present invention has excellent anti-cracking performance and a low friction coefficient in a high-temperature atmospheric environment.

[0214] In summary, the solution provided by the present invention has at least the following advantages:

[0215] (1) The high-strength, toughness, and wear-resistant silicon-doped diamond-like composite lubricating coating provided by the present invention can simultaneously have high hardness, toughness, wear resistance, and crack resistance, and the silicon-doped diamond-like composite lubricating coating has a dense structure. Compared with traditional DLC coatings, the silicon-doped diamond-like composite lubricating coating provided by the present invention has lower internal stress and higher toughness, and can effectively resist external wear and impact.

[0216] (2) The high-strength, tough, and wear-resistant silicon-doped diamond-like composite lubricating coating provided by the present invention can form a complete amorphous carbon transfer film in situ at the friction pair during friction, effectively reducing the friction coefficient and having excellent lubrication and friction reduction effects even at high temperatures.

[0217] (3) The highly tough and wear-resistant silicon-doped diamond-like carbon composite lubricating coating provided by the present invention is prepared using an ion-source-assisted high-power pulsed magnetron sputtering coating system. Compared with conventional magnetron sputtering equipment used in existing industrial production, the use of an ion-source-assisted high-power pulsed magnetron sputtering coating system increases the bombardment energy during the thin film deposition process, making it easier to prepare a hard nanocomposite lubricating coating with special properties.

[0218] (4) The present invention provides a preparation method using high-power pulsed magnetron sputtering technology assisted by an ion source. The coating deposited in a low-temperature environment (≤100°C) makes it suitable for flexible substrates such as polymer foils, thin glass, and textiles. It can also be applied to flexible electronic devices, flat panel displays, and flexible moving parts such as micro-electromechanical devices in a high-temperature environment, broadening its application range.

[0219] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A silicon-doped diamond-like composite lubricating coating, characterized in that: The silicon-doped diamond-like carbon composite lubricating coating comprises a SiC primer layer and a Si-DLC functional layer sequentially arranged on the surface of a substrate; The SiC base layer has a columnar structure, and the thickness of the SiC base layer is 0.3 μm to 0.4 μm; the Si-DLC functional layer has a dense featureless structure, and the thickness of the Si-DLC functional layer is 2.0 μm to 5.0 μm; In the SiC base layer, the mass percentage of Si is 25% to 35%, and the mass percentage of C is 65% to 75%; In the Si-DLC functional layer, the mass percentage of Si is 2% to 8%, and the mass percentage of DLC is 92% to 98%; The method for preparing the silicon-doped diamond-like carbon composite lubricating coating comprises the following steps: sequentially providing the SiC primer layer and the Si-DLC functional layer on the surface of a substrate; The SiC bottom layer is prepared by a DC magnetron sputtering method; The preparation conditions of the SiC bottom layer include: the vacuum degree in the equipment chamber is better than 1.0×10 -3 Pa, 50 sccm~80 sccm of argon gas is introduced into the equipment, and the gas pressure is maintained at 0.2Pa~0.3Pa; the substrate bias voltage is -50V~-100V, and the bias duty cycle is 50%~60%; the target current is 1.0A~2.0A, and the deposition time is 20min~30min; The target material is a graphite-silicon composite target, in which the Si content accounts for 35wt%~45wt%; The Si-DLC functional layer is prepared by adopting a high-power pulsed magnetron sputtering technology assisted by an anode ion source; The preparation conditions of the Si-DLC functional layer include: an argon gas flow rate of 50 sccm~80 sccm, a gas pressure of 0.2 Pa~0.3 Pa; a substrate bias voltage of -50 V~-100 V, and a bias duty cycle of 50%~60%; a C-Si composite target with a Si content of 5wt%~10wt%; a HiPIMS pulse power of 5.0 kW~8.0 kW, and a duty cycle of 1.0%~5.0%; an anode layer ion source power of 0.50 kW~0.75 kW corresponding to auxiliary ionization of the sputtering gas, and a duty cycle of 50%~60%; and a deposition time of 6 h~10 h.

2. The silicon-doped diamond-like composite lubricating coating according to claim 1, characterized in that: The silicon-doped diamond-like composite lubricating coating has at least one of the following characteristics: Feature 1: The hardness of the silicon-doped diamond-like composite lubricating coating is H , H The range is 18GPa~25GPa; Feature 2: The equivalent elastic modulus of the silicon-doped diamond-like composite lubricating coating is E* , H / E* ≥0.1; Feature 3: The elastic recovery coefficient of the silicon-doped diamond-like composite lubricating coating is We , We ≥60%; Feature 4: The silicon-doped diamond-like composite lubricating coating is in compressive stress as a whole; Feature 5: The silicon-doped diamond-like composite lubricating coating has a dense microstructure; Feature 6: The friction coefficient of the silicon-doped diamond-like carbon composite lubricating coating is 0.07-0.08 in an atmospheric environment at 25°C; Feature 7: The friction coefficient of the silicon-doped diamond-like carbon composite lubricating coating is 0.040-0.065 in an atmospheric environment at 450°C; Feature 8: The wear rate of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment of 25°C is no more than 10 -7 m 3 / N·m; Feature 9: The wear rate of the silicon-doped diamond-like composite lubricating coating in an atmospheric environment at 450°C is no more than 10 -6 m 3 / N·m; Feature 10: During the friction process, the silicon-doped diamond-like composite lubricating coating forms a complete amorphous carbon transfer film in situ at the friction pair.

3. The silicon-doped diamond-like composite lubricating coating according to claim 2, characterized in that: H is 18.0GPa~24.6GPa.

4. The silicon-doped diamond-like composite lubricating coating according to claim 2, characterized in that: H / E* is 0.102~0.

106.

5. The silicon-doped diamond-like composite lubricating coating according to claim 2, characterized in that: We is 76.5%~82.2%.

6. The silicon-doped diamond-like composite lubricating coating according to claim 2, characterized in that: The SiC base layer is in a tensile stress state, and the Si-DLC functional layer is in a compressive stress state.

7. The silicon-doped diamond-like composite lubricating coating according to claim 2, characterized in that: The friction coefficient of the silicon-doped diamond-like carbon composite lubricating coating in an atmospheric environment of 25° C. is 0.072-0.

079.

8. The silicon-doped diamond-like composite lubricating coating according to claim 2, characterized in that: The friction coefficient of the silicon-doped diamond-like carbon composite lubricating coating in an atmospheric environment at 450° C. is 0.040-0.

063.

9. A method for preparing a silicon-doped diamond-like composite lubricating coating according to any one of claims 1 to 8, characterized in that: The following steps are involved: sequentially disposing the SiC base layer and the Si-DLC functional layer on the surface of the substrate; The SiC bottom layer is prepared by a DC magnetron sputtering method; The preparation conditions of the SiC bottom layer include: the vacuum degree in the equipment chamber is better than 1.0×10 -3 Pa, 50 sccm~80 sccm of argon gas is introduced into the equipment, and the gas pressure is maintained at 0.2Pa~0.3Pa; the substrate bias voltage is -50V~-100V, and the bias duty cycle is 50%~60%; the target current is 1.0A~2.0A, and the deposition time is 20min~30min; The target material is a graphite-silicon composite target, in which the Si content accounts for 35wt%~45wt%; The Si-DLC functional layer is prepared by adopting a high-power pulsed magnetron sputtering technology assisted by an anode ion source; The preparation conditions of the Si-DLC functional layer include: an argon gas flow rate of 50 sccm~80 sccm, a gas pressure of 0.2 Pa~0.3 Pa; a substrate bias voltage of -50 V~-100 V, and a bias duty cycle of 50%~60%; a C-Si composite target with a Si content of 5wt%~10wt%; a HiPIMS pulse power of 5.0 kW~8.0 kW, and a duty cycle of 1.0%~5.0%; an anode layer ion source power of 0.50 kW~0.75 kW corresponding to auxiliary ionization of the sputtering gas, and a duty cycle of 50%~60%; and a deposition time of 6 h~10 h.

10. The preparation method according to claim 9, characterized in that Before preparing the SiC base layer, the substrate is pre-treated; The pretreatment includes grinding and polishing the substrate, then ultrasonic cleaning, and then placing the obtained substrate on a rotating rack in a vacuum chamber and performing plasma glow cleaning using an anode layer ion source.

11. The preparation method according to claim 10, characterized in that: Ultrasonic cleaning time is 40min~50min; And / or, plasma glow cleaning includes: placing the substrate into a vacuum chamber, and evacuating the vacuum to a value better than 1.0×10 -3 Pa, then introduce 100 sccm~150 sccm argon gas, and adjust the gas pressure to 0.36Pa~0.52Pa; at the same time, adjust the substrate bias to -1000V~-1200V, and the bias duty cycle to 50%~60%; then turn on the anode layer ion source, the anode layer ion source power is 0.8kW~1.0kW, the duty cycle is 50%~60%, and the plasma glow cleaning time is 30min~40min.

12. A use of the silicon-doped diamond-like composite lubricating coating according to any one of claims 1 to 8, characterized in that: The silicon-doped diamond-like composite lubricating coating is used to be arranged on a hard substrate or a flexible substrate in the fields of machinery, electronics, or medicine.

13. The use according to claim 12, characterized in that The hard substrate includes stainless steel or hard alloy.

14. The use according to claim 12, characterized in that The flexible substrate includes polymers, metal foils, flexible thin glass or textiles.

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