CN113235041A

CN113235041A - AlCrTiSiWMoN high-entropy alloy nitride coating and preparation method and application thereof

Info

Publication number: CN113235041A
Application number: CN202110379890.1A
Authority: CN
Inventors: 陈汪林; 伍卫凯; 王成勇; 邓阳
Original assignee: Guangdong University of Technology
Current assignee: Guangdong University of Technology
Priority date: 2021-04-08
Filing date: 2021-04-08
Publication date: 2021-08-10

Abstract

The invention discloses an AlCrTiSiWMoN high-entropy alloy nitride coating, which is formed by compounding an AlCrTiSiN priming coat and an AlCrTiSiWMoN working layer, wherein the AlCrTiSiN priming coat increases the thermal stability, the bearing capacity and the bonding force of the coating, and W and Mo are added into the AlCrTiSiWMoN working layer, so that the overall bonding force and red hardness of the coating can be improved, and self-lubricating WO is formed on the friction surface₃And MoO₃The oxidation product reduces the friction coefficient of the coating, the lubricating and antifriction functions of the coating not only reduce the cutting heat generated during cutting of the working layer of the coated cutter, but also improve the cutting life of the cutter, and the problems of poor binding force and red hardness and overhigh friction coefficient of the existing high-entropy alloy nitride coating are effectively solved.

Description

AlCrTiSiWMoN high-entropy alloy nitride coating and preparation method and application thereof

Technical Field

The invention belongs to the field of nitride hard coatings, and particularly relates to an AlCrTiSiWMoN high-entropy alloy nitride coating as well as a preparation method and application thereof.

Background

At present, the hard alloy cutter is faced with high cutting force and vibration in the use process, and particularly, a great friction loss and a thermal shock effect (the processing temperature can reach more than 1000 ℃) exist between a cutting edge and a processed workpiece, so that the cutter matrix is softened, the adhesive wear and the chemical wear are increased, and the quality of a product and the service life of the cutter are directly influenced. Thus, modern machining imposes properties such as red hardness, thermal stability, toughness, etc. on the cutting edge of the cutting tool.

In the existing preparation technology of cutter coatings, Physical Vapor Deposition (PVD) coatings have high surface hardness, good thermal stability and wear resistance, the service life of high-speed steel cutters and the quality of processed products are obviously prolonged, and meanwhile, the production cost is reduced. The current market mainstream cutter coating is as follows: the entropy alloy nitride coatings of three or four components such as AlCrN, TiSiN, CrTiN, AlCrSiN and the like have high internal stress and large brittleness, and the thermal stability of the coatings is poor, so that the requirement of high-speed processing of typical difficult-to-process materials such as stainless steel, quenched steel and the like is difficult to meet. Even if a small amount of five-element high-entropy alloy nitride coatings such as AlCrTiSiN and the like exist, the coatings are composed of nano composite structures composed of nanocrystalline embedded amorphous matrixes, the heat resistance of the coatings is poor, the coatings cannot bear the high temperature of 800 ℃, and otherwise, the performance of the cutter coatings is obviously degraded. In addition, the coating has the defects of red hardness and high-temperature oxidation resistance, and the wear coefficient of the coating is high.

In addition, to improve the adhesion of the coating to the substrate, a primer layer and a transition layer are typically deposited between the coating and the substrate. These underlying layers may be metals (Cr or AlCr, etc.) or their nitrides (CrN, AlCrN, etc.), but CrN decomposes to brittle Cr at 700 deg.C₂N phase, whereas AlCrN decomposes into brittle Cr at 800 deg.C₂N and hcp-AlN, resulting in a significant decrease in coating adhesion. CN109881148A discloses an AlCrTiSiN high-entropy alloy nitride coating with a single-phase solid solution structure and a preparation method and application thereof, the provided technical scheme improves the thermal stability and the coating bonding force of the entropy alloy nitride coating to a certain extent, but the bonding force and the red hardness are still to be further improved, and still face high friction coefficient, so that the cutting temperature is high during cutting, the cutter is seriously bonded and abraded, and further the cutter has short service life and is processedThe surface quality and the processing precision are low, and the like.

Disclosure of Invention

The invention aims to overcome the defects and defects of poor binding force and red hardness and high friction coefficient of a coating of the conventional high-entropy alloy nitride coating, and provides the AlCrTiSiWMoN high-entropy alloy nitride coating, wherein W and Mo are added into a working layer of the coating, so that the integral binding force and red hardness of the coating can be improved, and self-lubrication is formed on a friction surface₃And MoO₃The oxidation product reduces the friction coefficient of the coating, and the lubricating and antifriction effects of the coating not only reduce the cutting heat generated by the working layer of the coated cutter during cutting, but also improve the cutting life of the cutter.

The invention also aims to provide a preparation method of the AlCrTiSiWMoN high-entropy alloy nitride coating.

The invention further aims to provide application of the AlCrTiSiWMoN high-entropy alloy nitride coating in preparation of hard alloy products.

It is a further object of the present invention to provide a cemented carbide article.

In order to achieve the purpose, the invention adopts the following technical scheme:

an AlCrTiSiWMoN high-entropy alloy nitride coating is formed by compounding an AlCrTiSiN priming coat and an AlCrTiSiWMoN working layer.

The AlCrTiSiWMoN high-entropy alloy nitride coating is formed by compounding a specific priming coat and a working layer, the AlCrTiSiN increases the thermal stability, the bearing capacity and the bonding force of the coating, and the working layer of the AlCrTiSiWMoN is added with W and Mo, so that the bonding force and red hardness of the whole coating can be improved, and self-lubricating WO (tungsten oxide) is formed on the friction surface₃And MoO₃The oxidation product reduces the friction coefficient of the coating, the lubricating and antifriction functions of the coating not only reduce the cutting heat generated during cutting of the working layer of the coated cutter, but also improve the cutting life of the cutter, and the problems of poor binding force and red hardness and overhigh friction coefficient of the existing high-entropy alloy nitride coating are effectively solved.

Preferably, the AlCrTiSiN underlying layer is a single-phase solid solution with a face-centered cubic structure, and the AlCrTiSiWMoN working layer is a single-phase solid solution with a face-centered cubic structure.

The working layer is of a face-centered cubic structure, and the hardness, the wear resistance and the high-temperature oxidation resistance of the surface of the coating are improved, and the self-lubricating effect is achieved.

Preferably, the thickness of the AlCrTiSiN bottoming layer is less than or equal to 1 mu m, and the thickness of the AlCrTiSiWMoN working layer is 1-5 mu m.

In order to obtain a coating with more excellent comprehensive performance and realize the physical property matching of the working layer and the base coat layer, the thickness of the AlCrTiSiN base coat layer is preferably 50-1000 nm, and the thickness of the AlCrTiSiWMoN working layer is preferably 2-4 μm.

For example, the thickness of the AlCrTiSiN base coat is 50nm, and the thickness of the AlCrTiSiWMoN working layer is 3.2 μm; or the thickness of the AlCrTiSiN bottoming layer is 500nm, and the thickness of the AlCrTiSiWMoN working layer is 2.6 mu m; or the thickness of the AlCrTiSiN bottom layer is 1000nm, and the thickness of the AlCrTiSiWMoN working layer is 2.1 μm.

Preferably, the thickness of the AlCrTiSiN bottoming layer is 500-1000 nm, and the thickness of the AlCrTiSiWMoN working layer is 2-3 μm.

Preferably, the AlCrTiSiN primer layer comprises the following elements in atomic number percentage: 5-35% of Al, 5-25% of Cr, 5-25% of Ti, 1-5% of Si and 40-50% of N; the AlCrTiSiWMoN working layer comprises the following elements: 5-20% of Al, 5-20% of Cr, 5-20% of Ti, 1-5% of Si, 3-15% of W, 2-8% of Mo and 42-55% of N.

The single-phase solid solution structure can be ensured to be formed through element content control, and meanwhile, the red hardness and the binding force of the final coating can be improved and the related friction coefficient can be reduced through related element content.

The Si atom number percentage in the working layer is not more than 5%, mainly because elements such as Si, W, Mo and the like can generate coupling effect, an amorphous structure is easy to obtain, the structure of the original single-phase solid solution is damaged, and therefore the content of Si is required to be accurately and reasonably controlled. The addition of W and Mo in the working layer can form self-lubricating oxide on the friction surface, so that the friction reducing effect is achieved, the friction coefficient of the coating in the using process is further reduced, the service life of the cutter is prolonged, and the cutting quality is improved. Excess amounts of W and Mo tend to result in nanocomposite structures consisting of nanocrystalline inlaid amorphous matrices with poor resistance to high temperature oxidation, while insufficient amounts of W and Mo result in lower coating hardness.

Preferably, the AlCrTiSiN priming layer further comprises O with the content of O being less than or equal to 0.1% in terms of atomic number percentage, and the AlCrTiSiWMoN working layer further comprises O with the content of O being less than or equal to 0.1%. The oxygen content can influence the performance of the material, and the AlCrTiSiWMoN high-entropy alloy nitride coating has the oxygen content of less than 0.1 percent and meets the related control requirements.

The invention also specifically protects a preparation method of the AlCrTiSiWMoN high-entropy alloy nitride coating, which comprises the following steps:

s1: depositing an AlCrTiSiN priming coat on the surface of the substrate;

s2: co-depositing an AlCrTiSiWMoN working layer on the priming layer by utilizing an AlCr target, a TiSi target and a WMo target to obtain the AlCrTiSiWMoN high-entropy alloy nitride coating, wherein the bias voltage of a sample is-70 to-120V, the nitrogen pressure is 3.0 to 5.0Pa, the temperature of the sample is kept at 400 to 600 ℃, the AlCr target adopts permanent magnetism, the TiSi target and the WMo target adopt electromagnetism, the currents of the AlCr target and the TiSi target are 100A to 160A, the current of the WMo target is 150A to 250A, and the deposition lasts for 2 to 8 hours.

And during deposition, a direct-current power supply is started simultaneously, so that the ion concentration in the furnace is improved, the ionization rate of metal atoms is improved, and the compactness and hardness of the coating are enhanced.

Among them, it should be noted that:

in the S1 process of the present invention, the substrate is cleaned by argon ions, and the following methods can be referred to for specific cleaning:

vacuum degree less than 1 × 10^-3When Pa, introducing argon gas, controlling the flow at 50-200 sccm, the gas pressure at 0-2 Pa, the sample temperature at 500-550 ℃, and the negative cleaning bias sequentially: -100V, -300V, -500V and-800V, corresponding to washing times of 2min, 5min, 15min and 2 min.

The substrate material is preferably hard alloy, more preferably a hard alloy cutter, and the cutter further comprises the steps of sand blasting and ultrasonic cleaning before argon ion cleaning.

The AlCrTiSiN priming layer deposition in S1 preferably adopts the following method:

depositing an AlCrTiSiN single-phase solid solution priming layer by using a PVD (physical vapor deposition) technology: controlling the bias voltage of a sample to be-60 to-40V, introducing nitrogen, wherein the air pressure is 1.0 to 3.0Pa, the temperature of the sample is 450 to 500 ℃, the target current is 120 to 180A, the deposition time is 20 to 60min, and the deposition method is AlCr and TiSi target codeposition.

Wherein the AlCr alloy target is Al₇₀Cr₃₀The TiSi alloy target is Ti₈₂Si₁₈A target.

Preferably, in S2, the sample bias voltage is-80V, the air pressure is 3.0Pa, the sample temperature is 450 ℃, the target current is 160A, the deposition time is 2-8h, and the deposition method is AlCr, TiSi and WMo target codeposition.

Wherein the AlCr target is Al₇₀Cr₃₀The TiSi target is Ti₈₂Si₁₈Target, WMo target being W₈₀Mo₂₀A target.

The AlCrTiSiWMoN high-entropy alloy nitride coating has excellent binding force and red hardness, resists high temperature of 1000 ℃, has outstanding thermal stability and low friction coefficient, not only reduces the cutting heat generated by a working layer of a coated cutter during cutting, but also improves the cutting life of the cutter, and can be widely applied to the preparation of hard alloy products, especially hard alloy cutters.

The invention also specially protects a hard alloy product, such as a hard alloy cutter, and the AlCrTiSiWMoN high-entropy alloy nitride coating is deposited on the hard alloy product.

When the AlCrTiSiWMoN high-entropy alloy nitride coating is used as a hard alloy cutter coating, the cutter not only has excellent cutting performance and service life, but also ensures the cutting quality of a processed workpiece due to the low friction coefficient

Compared with the prior art, the invention has the following beneficial effects:

the invention provides an AlCrTiSiWMoN high-entropy alloy nitride coating which is formed by compounding an AlCrTiSiN priming coat and an AlCrTiSiWMoN working layer, wherein the AlCrTiSiN priming coat increases the thermal stability of the coatingThe bearing capacity and the binding force are improved, W and Mo are added into the AlCrTiSiWMoN working layer, the integral binding force and red hardness of the coating can be improved, and self-lubricating WO is formed on the friction surface₃And MoO₃The oxidation product reduces the friction coefficient of the coating, the lubricating and antifriction functions of the coating not only reduce the cutting heat generated during cutting of the working layer of the coated cutter, but also improve the cutting life of the cutter, and the problems of poor binding force and red hardness and overhigh friction coefficient of the existing high-entropy alloy nitride coating are effectively solved.

The AlCrTiSiWMoN high-entropy alloy nitride coating has the binding force reaching F1 level, the coating annealed at the temperature of 1000 ℃ for 2 hours still maintains the high hardness of 33.2GPa, the friction coefficient of high-temperature friction at the temperature of 500 ℃ is about 0.3, and the AlCrTiSiWMoN high-entropy alloy nitride coating has excellent binding force and red hardness and low friction coefficient and can be widely applied to preparing hard alloy products.

Drawings

FIG. 1 is a diagram of AlCrTiSiWMoN high entropy alloy nitride coating film-base bonding force test results.

FIG. 2 is a transverse interface TEM image and a selected electron diffraction image of the AlCrTiSiWMoN coating high-entropy alloy nitride coating after being subjected to heat preservation at 1000 ℃ for 2 hours.

FIG. 3 is an SEM image of the coating cross section of the AlCrTiSiWMoN high-entropy alloy nitride coating after being oxidized for 2 hours at 1000 ℃.

Detailed Description

The invention is further illustrated by the following examples. These examples are intended to illustrate the invention and are not intended to limit the scope of the invention. Experimental procedures without specific conditions noted in the examples below, generally according to conditions conventional in the art or as suggested by the manufacturer; the raw materials, reagents and the like used are, unless otherwise specified, those commercially available from the conventional markets and the like. Any insubstantial changes and substitutions made by those skilled in the art based on the present invention are intended to be covered by the claims.

Example 1

The high-entropy alloy nitride coating is formed by compounding an AlCrTiSiN bottoming layer and an AlCrTiSiWMoN working layer, wherein the AlCrTiSiN bottoming layer is a single-phase solid solution with a face-centered cubic structure, and the AlCrTiSiWMoN working layer is a single-phase solid solution with a face-centered cubic structure.

The thickness of the AlCrTiSiN bottom layer is 50nm, and the thickness of the AlCrTiSiWMoN working layer is 3.2 μm.

The AlCrTiSiN priming coat comprises the following elements in atomic number percentage: al 21.5 at.%, Cr 18.3 at.%, Ti 9.1 at.%, Si 1.9 at.%, N49.2 at.%; the AlCrTiSiWMoN working layer comprises the following elements: 18.9 at.% Al, 12.6 at.% Cr, 6.7 at.% Ti, 1.8 at.% Si, 7.3 at.% W, 6.0 at.% Mo, 46.7 at.% N.

The preparation method of the AlCrTiSiWMoN high-entropy alloy nitride coating comprises the following steps:

s1: depositing an AlCrTiSiN priming coat on the surface of the substrate: opening AlCr (Al) at the same time₇₀Cr₃₀Target) and TiSi target (Ti)₈₂Si₁₈Target) and opening a nitrogen switch to deposit the AlCrTiSiN single-phase solid solution priming layer with a columnar crystal structure, wherein the conditions are as follows: regulating the vacuum to 2.0Pa, maintaining the sample bias voltage to-60V, introducing nitrogen, controlling the air pressure to 2.0Pa, maintaining the sample temperature at 450 ℃, maintaining the target current at 160A, and depositing for 45 min;

s2: co-depositing an AlCrTiSiWMoN working layer on the priming layer by a composite target to obtain an AlCrTiSiWMoN high-entropy alloy nitride coating, and continuously depositing an AlCrSiWMoN single-phase solid solution working layer with a nano multilayer structure, wherein the conditions are as follows: vacuum was adjusted to 3.0Pa, the turret was opened and the AlCr target (Al) was opened simultaneously₇₀Cr₃₀Target), TiSi target (Ti)₈₂Si₁₈Target) and WMo target (W)₈₀Mo₂₀The target) is permanent magnet, the TiSi target and the WMo target are electromagnetism, the current of the AlCr target and the TiSi target is 160A, the current of the WMo target is 180A, the bias voltage of the sample is kept to be 80V, nitrogen is introduced, the flow rate of the nitrogen is 600sccm, the air pressure is controlled to be 3.0Pa, the temperature of the sample is kept to be 450 ℃, the current of the target material is 160A, and deposition is carried out for 2.0 h.

Wherein the substrate is treated as follows:

(1) carrying out dry sand blasting treatment on the hard alloy sheet, then carrying out ultrasonic cleaning and blow drying, and then inspecting the treated alloy sheet by a metallographic microscope, wherein the sample with good surface quality is reserved unless the surface of the sample has obvious defects.

(2) And (3) putting the cleaned hard alloy cutter into a PVD furnace, and cleaning with argon ions: when the background vacuum degree of the vacuum chamber of the PVD furnace is less than 1 multiplied by 10^-3When Pa, argon is introduced, the flow is controlled at 100sccm, the gas pressure is 0.3Pa, the sample temperature is 500 ℃, the negative bias is 800V, and the bombardment time is 20 min.

Example 2

The high-entropy alloy nitride coating is formed by compounding an AlCrTiSiN priming coat and an AlCrTiSiWMoN working layer, wherein the AlCrTiSiN priming coat is a single-phase solid solution with a face-centered cubic structure, and the AlCrTiSiWMoN working layer is a single-phase solid solution with a face-centered cubic structure.

The thickness of the AlCrTiSiN bottom layer is 500nm, and the thickness of the AlCrTiSiWMoN working layer is 2.6 μm.

The AlCrTiSiN priming layer comprises the following elements: al 21.5 at.%, Cr 18.3 at.%, Ti 9.1 at.%, Si 1.9 at.%, N49.2 at.%; the AlCrTiSiWMoN working layer comprises the following elements: al 20 at.%, Cr 10.5 at.%, Ti 6.3 at.%, Si 2.3 at.%, W7.5 at.%, Mo 7.5 at.%, N45.8 at.%.

The preparation method of the AlCrTiSiWMoN high-entropy alloy nitride coating is the same as that of the embodiment 1, wherein the current of the AlCr target and the TiSi target is 145A, and the current of the WMo target is 200A.

Example 3

The thickness of the AlCrTiSiN bottom layer is 1000nm, and the thickness of the AlCrTiSiWMoN working layer is 2.1 μm.

The AlCrTiSiN priming layer comprises the following elements: al 21.5 at.%, Cr 18.3 at.%, Ti 9.1 at.%, Si 1.9 at.%, N49.2 at.%; the AlCrTiSiWMoN working layer comprises the following elements: al 16.9 at.%, Cr 16.7 at.%, Ti 10.2 at.%, Si 2.1 at.%, W4.4 at.%, Mo 7.5 at.%, N46.1 at.%.

The preparation method of the AlCrTiSiWMoN high-entropy alloy nitride coating is the same as that of the embodiment 1, wherein the current of the AlCr target and the TiSi target is 160A, and the current of the WMo target is 150A.

Comparative example 1

The AlCrTiSiN high-entropy alloy nitride coating is formed by compounding an AlCrTiSiN priming coat and an AlCrTiSiN working layer, wherein the AlCrTiSiN priming coat is a single-phase solid solution with a face-centered cubic structure, and the AlCrTiSiN working layer is a single-phase solid solution with a face-centered cubic structure.

The thickness of the AlCrTiSiN priming layer is 50nm, and the thickness of the AlCrTiSiN working layer is 3.2 mu m.

Result detection

(1) Film-based bonding force

The high-entropy alloy nitride coatings of examples and comparative examples were subjected to a film-based bonding force test, and the test results are shown in table 1 below:

TABLE 1 Membrane-based binding force

Fig. 1 shows the film-based bonding force of the alcrtiisiwmon high entropy alloy nitride coating provided in example 1. The bonding force adopts a Rockwell indentation method, the test load is 150kg, and the figure shows that the periphery of the indentation has no obvious coating peeling and only a few cracks, which indicates that the coating has excellent bonding force reaching F1 grade and is excellent.

(2) Thermal stability

Fig. 2 is a TEM image of a cross-section of the alcrtiisiwmon coating high-entropy alloy nitride coating after being kept at 1000 ℃ for 2 hours and selected electron diffraction, provided in example 1. As can be seen from the figure, the coating still maintains a columnar crystal structure and no equiaxed crystal exists, which indicates that the AlCrTiSiWMoN coating does not recrystallize after being kept at 1000 ℃ for 2h and has excellent thermal stability. The selective electron diffraction pattern and high resolution phase further illustrate that the annealed coating still maintains a single phase solid solution structure. These show that the coatings have excellent thermal stability.

(3) Red hardness

And testing the hardness of the annealed coating by using an imported CSM nanoindenter, wherein the test load is 5 mN. The test result shows that the coating annealed at the temperature of 1000 ℃ for 2h still maintains high hardness, which indicates that the coating has excellent red hardness.

The results of the red hardness test of the high entropy alloy nitride coatings of examples and comparative examples are shown in table 2 below.

TABLE 2 Red hardness test results

Serial number	Red hardness/GPa
		Example 1	33.2GPa
Example 2	34.8GPa
		Example 3	32.9GPa
Comparative example 1	30.1GPa

The data in table 2 show that the alcrtiiswmon high entropy alloy nitride coating of the present invention has a very good red hardness, which can reach 34.8GPa, which is significantly higher than that of the alcrtiisn high entropy alloy nitride coating of comparative example 1.

(3) High temperature oxidation resistance

Fig. 3 is an SEM image of the coating cross-section of the alcrtiisiwmon high entropy alloy nitride coating provided in example 1 after oxidation at 1000 ℃ for 2 h. As can be seen, the coating structure after oxidation is compact, and only an oxidation layer with the thickness of 0.41 μm on the superficial layer exists. These show that the coating has excellent high temperature oxidation resistance. The thickness of the AlCrTiSiN high-entropy coating oxide layer of the comparative example 1 under the same oxidation condition is about 0.54 mu m, and the high-temperature oxidation resistance of the AlCrTiSiWMoN high-entropy alloy nitride coating is obviously inferior to that of the AlCrTiSiWMoN high-entropy alloy nitride coating.

(4) Coefficient of friction test

The coefficient of friction of alcrtiisiwmon high entropy alloy nitrides prepared in examples and comparative examples was measured by the following method:

500 ℃ high temperature frictional wear test

Specific detection results are shown in Table 3 below

TABLE 3 Friction coefficient test results

Serial number	Coefficient of friction
		Example 1	0.29
Example 2	0.27
		Example 3	0.31
Comparative example 1	0.39

The above data show that the coefficient of friction of the alcrtiisiwmon high entropy alloy nitride coating of the present invention can be controlled to about 0.3, while the coefficient of friction of the AlCrTiSiN high entropy alloy nitride coating without W and Mo added to reference 1 is 0.39, which shows that the alcrtiisiwmon high entropy alloy nitride coating of the present invention significantly reduces the coefficient of friction of the coating, and the lubricating and wear reducing effects thereof not only reduce the cutting heat generated during cutting of the coated tool working layer, but also improve the cutting life of the tool.

It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. The AlCrTiSiWMoN high-entropy alloy nitride coating is characterized by being formed by compounding an AlCrTiSiN base layer and an AlCrTiSiWMoN working layer.

2. The alcrtiisiimwmon high entropy alloy nitride coating of claim 1, wherein the alcrtiisin underlying layer is a single phase solid solution of face centered cubic structure and the alcrtiimwmon working layer is a single phase solid solution of face centered cubic structure.

3. The AlCrTiSiWMoN high-entropy alloy nitride coating of claim 1, wherein the thickness of the AlCrTiSiN priming layer is less than or equal to 1 μm, and the thickness of the AlCrTiSiWMoN working layer is 1-5 μm.

4. The AlCrTiSiWMoN high entropy alloy nitride coating of claim 3, wherein the thickness of the AlCrTiSiN base layer is 50-1000 nm, and the thickness of the AlCrTiSiWMoN working layer is 2-4 μm.

5. The AlCrTiSiWMoN high entropy alloy nitride coating of claim 4, wherein the thickness of the AlCrTiSiN base layer is 500-1000 nm, and the thickness of the AlCrTiSiWMoN working layer is 2-3 μm.

6. The alcrtiisiimpn high entropy alloy nitride coating of claim 1, wherein the AlCrTiSiN primer layer comprises the following elements in atomic number percent: 5-35% of Al, 5-25% of Cr, 5-25% of Ti, 1-5% of Si and 40-50% of N; the AlCrTiSiWMoN working layer comprises the following elements: 5-20% of Al, 5-20% of Cr, 5-20% of Ti, 1-5% of Si, 3-15% of W, 2-8% of Mo and 42-55% of N.

7. A preparation method of the AlCrTiSiWMoN high-entropy alloy nitride coating is characterized by comprising the following steps of:

s1: depositing an AlCrTiSiN priming coat on the surface of the substrate;

s2: co-depositing an AlCrTiSiWMoN working layer on the priming layer by utilizing an AlCr target, a TiSi target and a WMo target to obtain the AlCrSiWMoN high-entropy alloy nitride coating, wherein the bias voltage of a sample is-70 to-120V, the nitrogen pressure is 3.0 to 5.0Pa, the temperature of the sample is kept at 400 to 600 ℃, the AlCr target adopts permanent magnetism, the TiSi target and the WMo target adopt electromagnetism, the current of the AlCr target and the TiSi target is 100A to 160A, the current of the WMo target is 150A to 250A, and the deposition lasts for 2 to 8 hours.

8. The method for preparing the AlCrTiSiWMoN high-entropy alloy nitride coating as claimed in claim 7, wherein in S2, the sample bias voltage is-80V, the air pressure is 3.0Pa, the sample temperature is 450 ℃, the currents of the AlCr target and the TiSi target are 160A, the WMo target current is 200A, and the deposition time is 2-8 h.

9. Use of an alcrtiisiwmon high entropy alloy nitride coating according to any of claims 1 to 6 for the preparation of cemented carbide articles.

10. A hard alloy product, wherein the AlCrTiSiWMoN high-entropy alloy nitride coating is deposited on the hard alloy product according to any one of claims 1 to 6.