A carbide-based nanocomposite film, a preparation method and application thereof

Abstract

The application belongs to the technical field of protective materials, and particularly relates to a carbide-based nanocomposite film and a preparation method and application thereof. The carbide-based nanocomposite film provided by the application has a significant improvement in fracture toughness and further improvement in wear resistance on the premise of maintaining the high strength of carbide, and is a material with high hardness, high fracture toughness and high wear resistance. The carbide-based nanocomposite film is obtained by periodically introducing CrMnFeCoNi alloy nanolayers into carbide nanolayers through a magnetron sputtering technology. The carbide-based nanocomposite film provided by the application effectively combines the excellent fracture toughness of CrMnFeCoNi alloy, the high hardness and high wear resistance of carbide, and has a low and stable friction curve, good friction performance, can meet harsh service environments, and greatly improves the service life of materials and equipment.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of protective materials, and particularly relates to a carbide-based nanocomposite film and a preparation method and application thereof. BACKGROUND

[0002] The carbide coating has the characteristics of high hardness, high wear resistance and corrosion resistance, and is widely used in the fields of mechanical processing, cutting processing, welding and wear resistance. For example, on the blade of a gas turbine, the carbide coating can effectively enhance the wear resistance of the surface; on the surface of a mechanical part, the carbide coating can effectively prolong the service life of the part, etc.

[0003] However, due to the low fracture toughness of the carbide coating, cracks are easily generated and failure is caused in harsh service environments, such as the generation and expansion of micro-cracks on the surface of a tool or a bearing due to long-term mechanical load, thereby limiting the application of the carbide coating in the engineering field. SUMMARY

[0004] The application aims to provide a carbide-based nanocomposite film and a preparation method and application thereof. The carbide-based nanocomposite film provided by the application has high hardness, high wear resistance and high fracture toughness.

[0005] In order to achieve the above-mentioned purpose, the application provides the following technical scheme:

[0006] The application provides a carbide-based nanocomposite film, which comprises carbide nanolayers and CrMnFeCoNi alloy nanolayers arranged in an alternating stack; the molar ratio of Cr, Mn, Fe, Co and Ni in the CrMnFeCoNi alloy nanolayer is 18-22:18-22:18-22:18-22:18-22.

[0007] Preferably, the carbide nanolayer is a WC nanolayer.

[0008] Preferably, the number of layers of the CrMnFeCoNi alloy nanolayer is 40-95 layers; and the number of layers of the carbide nanolayer is 40-95 layers.

[0009] Preferably, the single-layer thickness of the carbide nanolayer is 15-25 nm; and the single-layer thickness of the CrMnFeCoNi alloy nanolayer is 3-20 nm.

[0010] The application further provides a preparation method of the carbide-based nanocomposite film described in the above scheme, comprising the following steps:

[0011] Carbide targets and CrMnFeCoNi targets are used as sputtering target materials, and the substrate is subjected to alternating magnetron sputtering, so as to obtain a carbide-based nanocomposite film on the surface of the substrate.

[0012] Preferably, the carbide target is a WC target, the distance between the carbide target and the substrate is 60-80mm; the distance between the CrMnFeCoNi target and the substrate is 60-80mm.

[0013] Preferably, the CrMnFeCoNi target and the carbide target use a direct current power supply; the sputtering current of the carbide target is 1.2-2.2A; the sputtering current of the CrMnFeCoNi target is 0.4-1.2A.

[0014] Preferably, the temperature of the substrate during the magnetron sputtering is 200-400℃.

[0015] Preferably, the magnetron sputtering is direct current magnetron sputtering; the magnetron sputtering is carried out in a protective atmosphere; the pressure of the magnetron sputtering is 0.6-1.2Pa; the bias power supply of the magnetron sputtering is-40--200V.

[0016] The application also provides the application of the carbide-based nanocomposite film prepared by the above preparation method as a protective coating.

[0017] The application provides a carbide-based nanocomposite film. The carbide-based nanocomposite film provided by the application comprises a CrMnFeCoNi alloy, and the content of each element in the CrMnFeCoNi alloy is the same or similar. Compared with a traditional alloy, the rich elements make the CrMnFeCoNi alloy have four unique effects, including high-entropy effect, lattice distortion effect, delayed diffusion effect and "cocktail" effect. These unique effects make the CrMnFeCoNi alloy have excellent fracture toughness, and the fracture toughness exceeds 200MPa√m.

[0018] The carbide-based nanocomposite film provided by the application adopts a nanomultilayer structure, and the CrMnFeCoNi alloy different from the carbide structure is periodically inserted in the carbide to construct a nanomultilayer film. There are different slip systems and significant lattice mismatches between the CrMnFeCoNi alloy nanolayer and the carbide nanolayer, which can introduce a large number of heterogeneous interfaces, which can hinder the sliding of dislocations, and the layer interface can also deflect or passivate cracks, so as to simultaneously improve the hardness and fracture toughness of the material. At the same time, the CrMnFeCoNi nanolayer has high fracture toughness and can provide toughness support; the carbide nanolayer has high hardness and can provide mechanical support.

[0019] The nanocomposite film constructed by the application can combine the advantages of each nanolayer, and improve the mechanical properties of the nanocomposite film through the synergistic effect of the nanolayers, so that the fracture toughness is significantly improved and the wear resistance is further improved under the premise of maintaining the high strength of the carbide, and the material has high hardness, high fracture toughness and high wear resistance, the hardness is above 18GPa, no cracks are generated around the micron indentation, has a low and stable friction curve, and has good friction performance.

[0020] The application also provides a preparation method of the carbide-based nanocomposite film. The carbide-based nanocomposite film provided by the application effectively combines the excellent fracture toughness of the CrMnFeCoNi alloy and the high hardness and high wear resistance of the carbide, no cracks are observed around the micron indentation, and the friction curve is low and stable, and the friction performance is good.

[0021] The application also provides an application of the carbide-based nanocomposite film or the carbide-based nanocomposite film prepared by the preparation method as a protective coating. The carbide-based nanocomposite film provided by the application has high hardness, high fracture toughness and high wear resistance, significantly reduces crack failure of the material under service working conditions, can meet harsh service environments, and greatly improves the service life of the material and equipment. BRIEF DESCRIPTION OF DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0023] Figure 1 The hardness column chart of the carbide-based nanocomposite film prepared in the embodiments 1-3 and the single-layer film of the comparative examples 1-2;

[0024] Figure 2 The SEM graph of the micron indentation of the carbide-based nanocomposite film prepared in the embodiments 1-3 and the single-layer film of the comparative examples 1-2;

[0025] Figure 3 The friction coefficient curve graph of the carbide-based nanocomposite film prepared in the embodiments 1-3 and the single-layer film of the comparative examples 1-2;

[0026] Figure 4 The cross-sectional SEM graph of the carbide-based nanocomposite film prepared in the embodiments 1-3;

[0027] Figure 5 A cross-sectional TEM image of the carbide-based nanocomposite film prepared for Example 1 of the present application. DETAILED DESCRIPTION

[0028] The present application provides a carbide-based nanocomposite film, comprising carbide nanolayers and CrMnFeCoNi alloy nanolayers alternately stacked; the molar ratio of Cr, Mn, Fe, Co and Ni in the CrMnFeCoNi alloy nanolayers is 18-22:18-22:18-22:18-22:18-22.

[0029] In the present application, the carbide nanolayers are preferably WC nanolayers.

[0030] In the present application, the molar ratio of Cr to Mn in the CrMnFeCoNi alloy nanolayers is preferably 18-22:18-22, and can be specifically 18:18, 18:19, 18:20, 18:21, 18:22, 19:18, 20:18, 21:18 or 22:18.

[0031] In the present application, the molar ratio of Cr to Fe in the CrMnFeCoNi alloy nanolayers is preferably 18-22:18-22, and can be specifically 18:18, 18:19, 18:20, 18:21, 18:22, 19:18, 20:18, 21:18 or 22:18.

[0032] In the present application, the molar ratio of Cr to Co in the CrMnFeCoNi alloy nanolayers is preferably 18-22:18-22, and can be specifically 18:18, 18:19, 18:20, 18:21, 18:22, 19:18, 20:18, 21:18 or 22:18.

[0033] In the present application, the molar ratio of Cr to Ni in the CrMnFeCoNi alloy nanolayers is preferably 18-22:18-22, and can be specifically 18:18, 18:19, 18:20, 18:21, 18:22, 19:18, 20:18, 21:18 or 22:18.

[0034] In the present application, the number of layers of the carbide nanolayer is preferably 40-95 layers, and can be specifically 40 layers, 45 layers, 48 layers, 52 layers, 55 layers, 60 layers, 65 layers, 70 layers, 75 layers, 80 layers, 85 layers, 90 layers or 95 layers; the number of layers of the CrMnFeCoNi alloy nanolayer is preferably 40-95 layers, and can be specifically 40 layers, 45 layers, 48 layers, 52 layers, 55 layers, 60 layers, 65 layers, 70 layers, 75 layers, 80 layers, 85 layers, 90 layers or 95 layers. One modulation unit is defined as one WC nanolayer and one CrMnFeCoNi alloy nanolayer arranged in an adjacent layer stack in the present application.

[0035] In the present application, the single-layer thickness of the carbide nanolayer is preferably 15-25 nm, and can be specifically 15 nm, 18 nm, 22 nm, 24 nm or 25 nm; the single-layer thickness of the CrMnFeCoNi alloy nanolayer is preferably 3-20 nm, and can be specifically 3 nm, 5 nm, 8 nm, 10 nm, 12 nm, 15 nm, 17 nm, 18 nm or 20 nm.

[0036] In the present application, the total thickness of the carbide-based nanocomposite film is preferably 1.6-2.4 μm, and can be specifically 1.6 μm, 1.7 μm, 1.8 μm, 1.9 μm, 2.0 μm, 2.1 μm, 2.2 μm, 2.3 μm or 2.4 μm.

[0037] The present application also provides a preparation method of the carbide-based nanocomposite film described in the above scheme, comprising the following steps:

[0038] The substrate is subjected to alternating magnetron sputtering with a carbide target and a CrMnFeCoNi target as sputtering target materials, so as to obtain a carbide-based nanocomposite film on the surface of the substrate.

[0039] In the present application, the carbide target and the CrMnFeCoNi target are preferably placed on a target table respectively; the carbide target is preferably a WC target; the distance between the carbide target and the substrate is preferably 60-80 mm, and can be specifically 60 mm, 65 mm, 70 mm, 75 mm or 80 mm; the distance between the CrMnFeCoNi target and the substrate is preferably 60-80 mm, and can be specifically 60 mm, 65 mm, 70 mm, 75 mm or 80 mm.

[0040] In the present application, the CrMnFeCoNi target and carbide target preferably use a direct current power supply; the sputtering current of the carbide target is preferably 1.2-2.2 A, and can be specifically 1.2 A, 1.4 A, 1.6 A, 1.7 A, 1.8 A, 1.9 A, 2.0 A or 2.2 A; the sputtering current of the CrMnFeCoNi target is preferably 0.4-1.2 A, and can be specifically 0.4 A, 0.5 A, 0.6 A, 0.7 A, 0.9 A, 1.1 A or 1.2 A.

[0041] In a specific embodiment of the present application, the purity of the WC target is preferably 99.999 wt%, and the purity of the CrMnFeCoNi target is preferably 99.999 wt%.

[0042] In the present application, the substrate is preferably a metal substrate; the metal substrate is preferably a titanium sheet; the substrate preferably undergoes pretreatment before use; the pretreatment preferably comprises sequentially performing first cleaning and drying.

[0043] In the present application, the first cleaning preferably comprises sequentially performing acetone ultrasonic cleaning and anhydrous ethanol ultrasonic cleaning; the time for the acetone ultrasonic cleaning is preferably 20-25 min, and can be specifically 20 min, 22 min or 25 min; the time for the anhydrous ethanol ultrasonic cleaning is preferably 20-25 min, and can be specifically 20 min, 22 min or 25 min.

[0044] In the present application, the drying is preferably blow drying; the gas used for the blow drying is preferably dry nitrogen.

[0045] In the present application, the substrate after the pretreatment is preferably placed on a substrate table of a magnetron sputtering system, ready for magnetron sputtering.

[0046] In the present application, the magnetron sputtering is preferably direct current magnetron sputtering; the equipment for the magnetron sputtering is preferably a magnetron sputtering system; the magnetron sputtering is preferably performed in a protective atmosphere; the protective atmosphere is preferably argon; the purity of the argon is preferably 99.995-99.999%.

[0047] In the present application, the temperature of the substrate during the magnetron sputtering is preferably 200-400℃, and can be specifically 200℃, 240℃, 270℃, 300℃, 330℃, 360℃ or 400℃.

[0048] In the present application, the pressure for the magnetron sputtering is preferably 0.6-1.2 Pa, and can be specifically 0.6 Pa, 0.8 Pa, 1.0 Pa or 1.2 Pa.

[0049] In the present application, the bias voltage of the magnetron sputtering is preferably -40 to -200 V, and can be specifically -40 V, -70 V, -100 V, -130 V, -160 V or -200 V.

[0050] In the specific embodiment of the present application, the magnetron sputtering is preferably performed by facing the sample holder to the carbide target for sputtering, then facing the sample holder to the CrMnFeCoNi target for sputtering, and then periodically rotating the sample holder for sputtering in the above-mentioned order.

[0051] In the present application, the magnetron sputtering preferably further comprises a second cleaning of the substrate before the magnetron sputtering; the second cleaning is preferably performed by vacuumizing the magnetron sputtering system, introducing a protective atmosphere at a flow rate of not higher than 8*10 -4 Pa, starting the ion source, and cleaning the substrate, and then adjusting the flow rate of the protective atmosphere to make the pressure in the magnetron sputtering system reach a target pressure.

[0052] In the present application, the protective atmosphere is preferably argon, and the purity of the argon is preferably 99.995% to 99.999%; the flow rate of the protective atmosphere is preferably 50 to 80 sccm, and can be specifically 50 sccm, 60 sccm, 70 sccm or 80 sccm.

[0053] In the present application, the ion source voltage of the second cleaning is preferably 700 to 900 V, and can be specifically 700 V, 750 V, 800 V, 850 V or 900 V; and the cleaning time is preferably 20 to 30 min, and can be specifically 20 min, 22 min, 25 min, 27 min or 30 min.

[0054] In the present application, the magnetron sputtering preferably further comprises taking out the product after the temperature of the magnetron sputtering system is cooled to room temperature.

[0055] The present application also provides the use of the carbide-based nanocomposite film prepared by the above-mentioned method as a protective coating.

[0056] The carbide-based nanocomposite film provided by the present application has high hardness, high fracture toughness and high wear resistance, significantly reduces the crack failure of the material under service working conditions, can meet the harsh service environment, and greatly improves the service life of the material and equipment.

[0057] In order to further illustrate the present application, the schemes of the present application are described in detail below in combination with the drawings and examples, but they should not be understood as limiting the scope of protection of the present application.

[0058] Example 1

[0059] This embodiment prepares a carbide-based nanocomposite film (denoted as WC / CrMnFeCoNi), including the following steps:

[0060] Titanium sheets were used as substrates. Before use, the titanium sheets were cleaned in an ultrasonic cleaner with acetone and anhydrous ethanol for 25 minutes each. After cleaning, the substrates were dried with dry nitrogen gas and then placed on the substrate stage of the magnetron sputtering system for magnetron sputtering.

[0061] A WC target (99.999 wt% purity) and a CrMnFeCoNi target (99.999 wt% purity, molar ratio of elements 1:1:1:1:1) were placed on the target stage. The spacing between the CrMnFeCoNi target and the substrate was 70 mm. The sputtering current used for the WC target was 1.8 A, and the sputtering current used for the CrMnFeCoNi target was 0.4 A. The vacuum level in the magnetron sputtering system did not exceed 8 × 10⁻⁶. -4 At a pressure of 0.8 Pa, argon gas (99.999% purity) was introduced and the flow rate was set to 80 sccm. The ion source was turned on to perform a second cleaning of the substrate. The ion source voltage for the second cleaning was 800 V, and the cleaning time was 20 min. Then, the substrate temperature was set to 200 °C, and the argon gas flow rate was adjusted to make the pressure in the magnetron sputtering system 0.8 Pa. The bias power supply was -100 V. The substrate was alternately magnetron sputtered using WC and CrMnFeCoNi targets, respectively. The thickness of the WC nanolayer was 22 nm, and the thickness of the CrMnFeCoNi alloy nanolayer was 5 nm. A carbide-based nanocomposite film with a total thickness of 2 μm was obtained on the substrate surface. After the temperature in the magnetron sputtering system cooled to room temperature, the carbide-based nanocomposite film was removed.

[0062] The carbide-based nanocomposite film prepared in this embodiment was subjected to micron-indentation, nano-indentation, and tribological tests, and the results are as follows: Figures 1-3 As shown. According to Figure 1 It can be seen that the hardness of the carbide-based nanocomposite film prepared in this embodiment is 23.3 GPa. According to... Figure 2 As can be seen, no cracks were observed around the micron-sized indentation, and the carbide-based nanocomposite film prepared in this embodiment exhibits high hardness and excellent fracture toughness. According to Figure 3 As can be seen, the friction curve of the carbide-based nanocomposite film prepared in this embodiment remains stable, indicating that the carbide-based nanocomposite film prepared in this embodiment has a low coefficient of friction and excellent tribological properties of low wear and wear resistance.

[0063] The cross-section of the carbide-based nanocomposite film prepared in this embodiment was measured by SEM, and the results are as follows: Figure 4 As shown. According to Figure 4It can be seen that the CrMnFeCoNi nanolayers and the WC nanolayers are alternately deposited to form a multilayer structure, and the total thickness of the carbide-based nanocomposite film is 2 μm.

[0064] TEM test was performed on the cross section of the carbide-based nanocomposite film prepared in this example, and the result is shown in FIG. 4. Figure 5 Figure 5 It can be seen that there are obvious light and dark alternating stripes in the figure, which confirms that the carbide-based nanocomposite film is grown in layers, wherein the brighter layers are the CrMnFeCoNi alloy nanolayers, and the darker layers are the WC nanolayers.

[0065] Example 2

[0066] The preparation method of this example is the same as that of Example 1, except that the sputtering current of the CrMnFeCoNi target used in the preparation process of this example is 0.68 A; in the carbide-based nanocomposite film prepared, the thickness of the WC nanolayer is 22 nm, the thickness of the CrMnFeCoNi nanolayer is 10 nm, and the total thickness is 2 μm.

[0067] Microindentation, nanoindentation and friction test were performed on the carbide-based nanocomposite film prepared in this example, and the results are shown in FIG. 5. Figures 1-3 Figure 1 It can be seen that the hardness of the carbide-based nanocomposite film prepared in this example is 21.2 GPa. According to Figure 2 It can be seen that no cracks are observed around the microindentation, and the carbide-based nanocomposite film prepared in this example exhibits high hardness and excellent fracture toughness. According to Figure 3 It can be seen that the friction curve of the carbide-based nanocomposite film prepared in this example remains stable, and the friction coefficient is low, indicating that the carbide-based nanocomposite film prepared in this example has excellent tribological properties of low wear and abrasion resistance.

[0068] SEM test was performed on the cross section of the carbide-based nanocomposite film prepared in this example, and the result is shown in FIG. 6. Figure 4 Figure 4 It can be seen that the CrMnFeCoNi nanolayers and the WC nanolayers are alternately deposited to form a multilayer structure, and the total thickness of the carbide-based nanocomposite film is 2 μm.

[0069] Example 3

[0070] The preparation method of this example is the same as that of Example 1, except that the sputtering current of the CrMnFeCoNi target used in the preparation process of this example is 1.2 A; in the carbide-based nanocomposite film prepared, the thickness of the WC nanolayer is 22 nm, the thickness of the CrMnFeCoNi nanolayer is 18 nm, and the total thickness is 2 μm.

[0071] ​​​The carbide-based nanocomposite film prepared in the embodiment was subjected to microindentation, nanoindentation and friction test, and the results are shown in Figures 1-3 Figure 1 It can be seen that the hardness of the carbide-based nanocomposite film prepared in the embodiment is 18.5 GPa. According to Figure 2 It can be seen that no crack is observed around the microindentation, and the carbide-based nanocomposite film prepared in the embodiment exhibits high hardness and excellent fracture toughness. According to Figure 3 It can be seen that the friction curve of the carbide-based nanocomposite film prepared in the embodiment remains stable, and the friction coefficient is low, indicating that the carbide-based nanocomposite film prepared in the embodiment has excellent tribological properties of low wear and abrasion resistance.

[0072] The cross section of the carbide-based nanocomposite film prepared in the embodiment was subjected to SEM test, and the results are shown in Figure 4 Figure 4 It can be seen that the CrMnFeCoNi nanolayer and the WC nanolayer are alternately deposited to form a multilayer structure, and the total thickness of the carbide-based composite film is 2 μm.

[0073] Example 4

[0074] The preparation method of the embodiment is the same as that of Example 1, except that the sputtering current of the CrMnFeCoNi target is 0.4 A and the sputtering current of the WC target is 1.5 A during the preparation of the embodiment; the thickness of the WC nanolayer in the prepared carbide-based nanocomposite film is 18 nm, the thickness of the CrMnFeCoNi nanolayer is 5 nm, and the total thickness is 2 μm. The test data of the embodiment is similar to that of Example 1.

[0075] Example 5

[0076] The preparation method of the embodiment is the same as that of Example 1, except that the sputtering current of the CrMnFeCoNi target is 0.68 A and the sputtering current of the WC target is 2.1 A during the preparation of the embodiment; the thickness of the WC nanolayer in the prepared carbide-based nanocomposite film is 25 nm, the thickness of the CrMnFeCoNi nanolayer is 10 nm, and the total thickness is 2 μm. The test data of the embodiment is similar to that of Example 2.

[0077] Comparative Example 1

[0078] The CrMnFeCoNi single-layer film was prepared in the comparative example, including the following steps:

[0079] Titanium sheets were used as substrates, and the titanium sheets were cleaned in an ultrasonic cleaner with acetone and anhydrous ethanol respectively before use, each for 25 min. After cleaning, the substrates were blown dry with dry nitrogen, and then placed on the substrate table of the magnetron sputtering system for magnetron sputtering.​​

[0080] A CrMnFeCoNi target (purity of 99.999wt%, molar ratio of each element of 1:1:1:1:1) was placed on a target table, the distance between the CrMnFeCoNi target and the substrate was 70 mm, the sputtering current of the CrMnFeCoNi target was 1.2 A, the vacuum degree in the magnetron sputtering system was not higher than 8x10 -4 When the temperature of the substrate reached 200 ℃, the flow rate of argon gas (purity of 99.999%) was set to 80 sccm, the ion source was turned on, and the substrate was subjected to a second cleaning. The ion source voltage of the second cleaning was 800 V, and the cleaning time was 20 min. Then, the temperature of the substrate was set to 200 ℃, the flow rate of argon gas was adjusted to make the pressure in the magnetron sputtering system 0.8 Pa, the bias power was -100 V, and the CrMnFeCoNi target was used for magnetron sputtering. A CrMnFeCoNi monolayer film was obtained on the surface of the substrate, and the total thickness was 2 μm. After the temperature in the magnetron sputtering system cooled to room temperature, the CrMnFeCoNi monolayer film was taken out.

[0081] The CrMnFeCoNi monolayer film prepared in the present comparative example was subjected to micro indentation, nano indentation and friction test, and the results are shown in Figures 1-3 As can be seen from Figure 1 , the hardness of the CrMnFeCoNi monolayer film prepared in the present comparative example was 7.3 GPa. As can be seen from Figure 2 , no cracks were observed around the micro indentation. As can be seen from Figure 3 , the friction curve of the CrMnFeCoNi monolayer film prepared in the present comparative example had a higher friction coefficient, and the friction performance was poor.

[0082] Comparative Example 2

[0083] A WC monolayer film was prepared in the present comparative example, including the following steps:

[0084] Titanium sheets were used as substrates, and before use, the titanium sheets were cleaned in an ultrasonic cleaner with acetone and anhydrous ethanol respectively for 25 min. After cleaning, the substrates were dried with dry nitrogen, and then placed on the substrate table of the magnetron sputtering system for magnetron sputtering.

[0085] A WC target (purity of 99.999wt%) was placed on a target table, the distance between the WC target and the substrate was 70 mm, the sputtering current of the WC target was 1.8 A, the vacuum degree in the magnetron sputtering system was not higher than 8x10 -4Pa, argon (purity 99.999%) was introduced, the flow rate of argon was set to 80sccm, the ion source was turned on, the substrate was subjected to a second cleaning, the ion source voltage of the second cleaning was 800V, the cleaning time was 20min, then the temperature of the substrate was set to 200℃, the flow rate of argon was adjusted to make the pressure in the magnetron sputtering system 0.8Pa, the bias power was -100V, the substrate was subjected to magnetron sputtering using a WC target, a WC monolayer film was obtained on the surface of the substrate, the total thickness was 2μm, after the temperature in the magnetron sputtering system cooled to room temperature, the WC monolayer film was taken out.

[0086] The WC monolayer film prepared in the present comparative example was subjected to microindentation, nanoindentation and friction test, and the results are shown in Figures 1-3 Figure 1 It can be seen that the hardness of the WC monolayer film prepared in the present comparative example is 25.6GPa. Figure 2 It can be seen that cracks appeared around the microindentation, and the fracture toughness is poor. Figure 3 It can be seen that the friction coefficient of the WC monolayer film prepared in the present comparative example is low, and the friction performance is good.

[0087] From the above examples, it can be seen that the carbide-based nanocomposite film provided by the present application has high hardness, high fracture toughness and high wear resistance, the hardness is above 18GPa, no cracks appear around the microindentation, has a stable friction curve, the friction coefficient is low, the friction performance is good, and can meet the harsh service environment.

[0088] Although the above examples have made a detailed description of the present application, it is only a part of the embodiments of the present application, but not all the embodiments, and other embodiments can be obtained according to the present embodiments without creativity, and these embodiments all belong to the protection scope of the present application.​

Claims

1. A carbide-based nanocomposite film, characterized by, The CrMnFeCoNi alloy nanolayer comprises Cr, Mn, Fe, Co and Ni in a molar ratio of 18-22:18-22:18-22:18-22:18-22. The CrMnFeCoNi alloy nanolayer comprises Cr, Mn, Fe, Co and Ni in a molar ratio of 18-22:18-22:18-22:18-22:18-22. The number of layers of the CrMnFeCoNi alloy nanolayer is 40-95 layers; the number of layers of the carbide nanolayer is 40-95 layers; the carbide nanolayer is a WC nanolayer; the single-layer thickness of the carbide nanolayer is 15-25 nm. The single-layer thickness of the CrMnFeCoNi alloy nanolayer is 3-20 nm.

2. The method of claim 1, wherein the carbide-based nanocomposite film is prepared by a process comprising: The method comprises the following steps: The substrate is subjected to alternating magnetron sputtering using a carbide target and a CrMnFeCoNi target as sputtering targets to obtain a carbide-based nanocomposite film on the surface of the substrate.

3. The production method according to claim 2, characterized by, The carbide target is a WC target, the distance between the carbide target and the substrate is 60-80 mm, and the distance between the CrMnFeCoNi target and the substrate is 60-80 mm.

4. The production method according to claim 2 or 3, characterized by, The CrMnFeCoNi target and the carbide target use a direct current power supply; the sputtering current of the carbide target is 1.2-2.2 A; and the sputtering current of the CrMnFeCoNi target is 0.4-1.2 A.

5. The preparation method according to claim 2, characterized in that, The temperature of the substrate during the magnetron sputtering is 200-400°C.

6. The production method according to claim 2 or 5, characterized by, The magnetron sputtering is direct current magnetron sputtering; the magnetron sputtering is carried out in a protective atmosphere; the pressure of the magnetron sputtering is 0.6-1.2 Pa; and the bias voltage of the magnetron sputtering is -40--200 V.

7. Use of the carbide-based nanocomposite film of claim 1 or the carbide-based nanocomposite film obtained by the preparation method of any one of claims 2-6 as a protective coating.

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