AlCrTiXN coating for cutting titanium alloy and production process

Abstract

The present invention relates to an AlCrTiXN coating and a production process for cutting titanium alloy TC4, and belongs to the technical field of titanium alloy coatings. The preparation of the production process includes the following steps: degreasing, degreasing, and cleaning the tool, and then performing soft sandblasting treatment, immersing the tool in a mixed solution under an inert atmosphere for ultrasonic treatment, taking it out and cleaning it, and then vacuum drying it to obtain a pretreated carbide milling cutter; in an inert atmosphere, placing the pretreated carbide milling cutter into a vacuum chamber, turning on the nitrogen gas source, and simultaneously turning on the CrAl composite target arc power supply and the TiZr alloy target power supply for deposition treatment; turning off all target materials, turning off the bias power supply and gas source, performing heat preservation treatment and then cooling with the furnace, taking out the tool, and cooling it at room temperature to obtain a gradient coating. The gradient coating prepared by the present invention exhibits stronger bonding with the tool substrate, and at the same time has excellent chemical stability, anti-adhesion performance and wear resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of titanium alloy coatings and relates to an AlCrTiXN coating for cutting titanium alloys and a production process. Background Art

[0002] Titanium alloy is a high-strength, lightweight material with excellent heat and corrosion resistance. It is widely used in a variety of fields, including aviation, aerospace, automotive, chemistry, and biology. In particular, the use of titanium alloys in aerospace is increasing year by year. Using titanium alloys in aircraft parts not only extends the life of an aircraft but also reduces its weight, lowering fuel consumption and significantly improving flight performance.

[0003] However, with the advancement of high-speed cutting technology and the increasing demand for thin-walled integral parts, the difficulty of titanium alloy processing has become more prominent. Its high strength, low thermal conductivity, high chemical activity and low elastic modulus are the key factors that make titanium alloy cutting difficult. At present, although coated tools are available on the market for cutting titanium alloys, these tools still face problems such as insufficient wear resistance, easy oxidation and easy shedding. With the rapid development of the manufacturing industry, the application of titanium alloys will increase, and the requirements for quality and precision will continue to increase. Therefore, choosing more suitable titanium alloy cutting tools, improving the industry's industrial production level, and reducing titanium alloy manufacturing costs are of far-reaching significance to the continued development of mechanical processing and the improvement of the overall level of the manufacturing industry.

[0004] When carbide cutting tools used to cut titanium alloys are exposed to air or aqueous solutions, a dense oxide film forms on their surface. This film is very strong. The oxide film is even thicker on the surface of parts that have been cast and heat-treated. Once the oxide film is damaged by mechanical damage, it can quickly repair itself, making it difficult to remove. After the oxide film on the surface of the carbide tool is removed using inorganic acid etching, a new oxide film will immediately form on the fresh surface upon contact with air, water, or aqueous solutions. To achieve good coating adhesion, the oxide film on the carbide tool surface must first be thoroughly removed, and secondly, the alloy surface must be kept active to ensure stability before the deposition of the coating metal. Therefore, the pretreatment method of the carbide tool directly affects the adhesion between the subsequent metal coating and the carbide tool substrate. Summary of the Invention

[0005] The purpose of the present invention is to provide an AlCrTiXN coating and a production process for cutting titanium alloys. The gradient coating prepared by the present invention exhibits stronger bonding with the cemented carbide tool substrate and has excellent chemical stability, anti-adhesion performance and wear resistance.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A production process for cutting an AlCrTiXN coating for titanium alloy TC4 comprises the following steps:

[0008] 1) Degreasing, degreasing, and cleaning the cutting tool, followed by soft sandblasting, immersing the tool in a mixed solution under an inert atmosphere, ultrasonically treating the tool, removing the tool from the mixed solution, cleaning the tool, and vacuum drying the tool to obtain a pretreated cemented carbide cutting tool;

[0009] 2) Under an inert atmosphere, the pretreated carbide tool is placed in a vacuum chamber, and the arc power supply of the ALCr composite target and the power supply of the TiZr alloy target are turned on simultaneously for deposition treatment;

[0010] 3) Turn off all targets, bias power supply and gas source, keep the temperature at 350-380℃ for 15-30min, then cool down to below 100℃ with the furnace, take out the tool, cool at room temperature to obtain the gradient coating.

[0011] As a preferred technical solution of the present invention, in step 1), the tool is a milling cutter specially used for titanium alloy cutting; the soft sand blasting is sand blasting at a pressure of 0.16-0.20 MPa for 24-30 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is ultrasonic treatment at a temperature of 40-50°C and a power of 400-500W for 30-40 seconds; and the vacuum drying is vacuum drying at a temperature of 80°C to constant weight.

[0012] As a preferred technical solution of the present invention, in step 1), the mixed solution is composed of hydrochloric acid, oxalic acid, an auxiliary agent and a solvent in a mass ratio of 40-42:25-28:6.2-7.0:1000; the solvent is a 20wt% ethanol aqueous solution; the auxiliary agent is a mixture of a thiophenol derivative and sodium lauryl sulfate in a mass ratio of 2.0-2.3:1.4-1.5; the preparation of the benzenethiol derivative comprises mixing protocatechuic aldehyde and anhydrous ethanol, adding m-aminothiophenol, stirring at a temperature of 50-60°C for 4-5 hours, and centrifuging to obtain the product; the mass ratio of protocatechuic aldehyde, m-aminothiophenol and anhydrous ethanol is 1.8:2.5:20.

[0013] As a preferred technical solution of the present invention, in step 2), the parameters of the ALCr composite target arc power supply are 90-120A current, the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 2-3A / min, and the tool substrate is treated for 150 minutes; the working gas pressure in the vacuum chamber is 0.8-1.2Pa, and the bias voltage is 60-100V.

[0014] As a preferred technical solution of the present invention, the thickness of the gradient coating is 120-160 nm, and the atomic percentage of each element in the gradient coating is: Al is 16.2-16.6 at.%, Cr is 9.4-10 at.%, Zr is 18.5-18.8 at.%, Ti is 10.66-10.68 at.%, and the rest is N element.

[0015] Beneficial effects of the present invention:

[0016] (1) The gradient coating prepared by the present invention exhibits stronger bonding strength with the cemented carbide tool substrate and has excellent chemical stability, anti-adhesion performance and wear resistance.

[0017] (2) The present invention can improve the etching effect of oxalic acid through hydrochloric acid, and sodium dodecyl sulfate can reduce its surface tension, improve its wettability and permeability, and promote hydrochloric acid and oxalic acid to better contact and dissolve the surface oxide layer; the benzene thiol derivative contains a thiol group, an imine structure and forms a stable complex with metal ions, which prevents the metal ions from re-depositing on the surface during the treatment process, thereby improving the removal effect of the oxide layer. It also contains a catechol structure with antioxidant properties, which can prevent the treated surface from being oxidized again and maintain the activity of the surface. The adsorption effect of the inhibitor and the metal can be enhanced through the synergistic effect of the imine structure, the thiol group and the catechol structure. It can also be adapted to the adsorption of various metals, reduce their oxidative corrosion, and provide protection for titanium alloy metals. DETAILED DESCRIPTION

[0018] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with the embodiments.

[0019] Example 1

[0020] A production process for cutting an AlCrTiXN coating for titanium alloy TC4 comprises the following steps:

[0021] 1) Degreasing, degreasing, and cleaning a hard tungsten-cobalt alloy tool YG8, followed by soft sandblasting, immersing the tool in a mixed solution under an inert atmosphere, ultrasonically treating the solution, filtering the solution, and then vacuum drying the solution at 80° C. to a constant weight to obtain a pretreated hard alloy tool;

[0022] 2) Under an inert atmosphere, place the pretreated carbide tool in a vacuum chamber, turn on the nitrogen gas source, and simultaneously turn on the ALCr composite target arc power supply and the TiZr alloy target power supply for deposition;

[0023] 3) Turn off all targets, bias power supply and gas source, keep the temperature at 350°C for 15 minutes, then cool down to below 100°C with the furnace, take out the tool, and cool it at room temperature to obtain a gradient coating.

[0024] In step 1), the soft sand blasting is performed at a pressure of 0.16 MPa for 24 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is performed at a temperature of 40°C and a power of 400 W for 30 seconds; the mixed solution comprises hydrochloric acid, oxalic acid, an auxiliary agent, and a solvent in a mass ratio of 40:25:6.2:1000; the solvent is a 20wt% ethanol aqueous solution; the auxiliary agent is a mixture of a thiophenol derivative and sodium lauryl sulfate in a mass ratio of 2.0:1.4; the preparation of the benzenethiol derivative comprises mixing protocatechuic aldehyde and anhydrous ethanol, adding m-aminothiophenol, stirring at a temperature of 50°C for 4 hours, and centrifuging to obtain the obtained product; the mass ratio of protocatechuic aldehyde, m-aminothiophenol, and anhydrous ethanol is 1.8:2.5:20.

[0025] In step 2), the parameters of the ALCr composite target arc power supply are 90A current, the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 2A / min, and the tool substrate is treated for 150 minutes; the working gas pressure in the vacuum chamber is 0.8Pa and the bias voltage is 80V.

[0026] The thickness of the gradient coating is 120 nm, and the atomic percentages of the elements in the gradient coating are: Al is 16.2 at.%, Cr is 9.4 at.%, Zr is 18.5 at.%, and Ti is 10.66 at.%.

[0027] Example 2

[0028] A production process for cutting an AlCrTiXN coating for titanium alloy TC4 comprises the following steps:

[0029] 1) Degreasing, degreasing, and cleaning a YG8 hard tungsten-cobalt alloy tool, followed by soft sandblasting, immersing the tool in a mixed solution under an inert atmosphere for ultrasonic treatment, removing the tool from the mixed solution for cleaning, and vacuum drying the tool at 80° C. to a constant weight to obtain a pretreated hard alloy tool;

[0030] 2) Under an inert atmosphere, place the pretreated carbide tool in a vacuum chamber, turn on the nitrogen gas source, and simultaneously turn on the ALCr composite target arc power supply and the TiZr alloy target power supply for deposition;

[0031] 3) Turn off all targets, bias power supply and gas source, keep the temperature at 358°C for 19 minutes, then cool down to below 100°C with the furnace, take out the tool, and cool it at room temperature to obtain a gradient coating.

[0032] In step 1), the soft sand blasting is performed at a pressure of 0.17 MPa for 26 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is performed at a temperature of 42°C and a power of 425 W for 32 seconds; the mixed solution comprises hydrochloric acid, oxalic acid, an auxiliary agent, and a solvent in a mass ratio of 40.5:25.8:6.4:1000; the solvent is a 20wt% ethanol aqueous solution; the auxiliary agent is a mixture of a thiophenol derivative and sodium lauryl sulfate in a mass ratio of 2.1:1.42; the preparation of the benzenethiol derivative comprises mixing protocatechuic aldehyde and anhydrous ethanol, adding m-aminothiophenol, stirring at a temperature of 52°C for 4.2 hours, and centrifuging to obtain the obtained product; the mass ratio of protocatechuic aldehyde, m-aminothiophenol, and anhydrous ethanol is 1.8:2.5:20.

[0033] In step 2), the parameters of the AlCr composite target arc power supply are 98A current, and the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 2.2A / min, and the tool substrate is treated for 150 minutes; the working gas pressure in the vacuum chamber is 0.9Pa and the bias voltage is 90V.

[0034] The thickness of the gradient coating is 130 nm, and the atomic percentage of each element in the gradient coating is: Al is 16.3 at.%, Cr is 9.6 at.%, Zr is 18.57 at.%, Ti is 10.665 at.%, and the rest is N element.

[0035] Example 3

[0036] A production process for cutting an AlCrTiXN coating for titanium alloy TC4 comprises the following steps:

[0037] 1) Degreasing, degreasing, and cleaning a YG8 hard tungsten-cobalt alloy tool, followed by soft sandblasting, immersing the tool in a mixed solution under an inert atmosphere for ultrasonic treatment, removing the tool from the mixed solution for cleaning, and vacuum drying the tool at 80° C. to a constant weight to obtain a pretreated hard alloy tool;

[0038] 2) Under an inert atmosphere, place the pretreated carbide tool in a vacuum chamber, turn on the nitrogen gas source, and simultaneously turn on the AlCr composite target arc power supply and the TiZr alloy target power supply for deposition;

[0039] 3) Turn off all targets, bias power supply and gas source, keep the temperature at 365°C for 22 minutes, then cool down to below 100°C with the furnace, take out the tool, and cool it at room temperature to obtain a gradient coating.

[0040] In step 1), the soft sand blasting is performed at a pressure of 0.18 MPa for 27 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is performed at a temperature of 45°C and a power of 450 W for 35 seconds; the mixed solution comprises hydrochloric acid, oxalic acid, an auxiliary agent, and a solvent in a mass ratio of 41:26.5:6.6:1000; the solvent is a 20wt% ethanol aqueous solution; the auxiliary agent is a mixture of a thiophenol derivative and sodium lauryl sulfate in a mass ratio of 2.15:1.45; the preparation of the benzenethiol derivative comprises mixing protocatechuic aldehyde and anhydrous ethanol, adding m-aminothiophenol, stirring at a temperature of 55°C for 4.5 hours, and centrifuging to obtain the obtained product; the mass ratio of protocatechuic aldehyde, m-aminothiophenol, and anhydrous ethanol is 1.8:2.5:20.

[0041] In step 2), the parameters of the AlCr composite target arc power supply are 105A current, the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 2.5A / min, and the tool substrate is treated for 150 minutes; the working gas pressure in the vacuum chamber is 1Pa, and the bias voltage is 100V.

[0042] The thickness of the gradient coating is 140 nm, and the atomic percentage of each element in the gradient coating is: Al is 16.4 at.%, Cr is 9.7 at.%, Zr is 18.65 at.%, Ti is 10.67 at.%, and the rest is N element.

[0043] Example 4

[0044] A production process for cutting an AlCrTiXN coating for titanium alloy TC4 comprises the following steps:

[0045] 1) Degreasing, degreasing, and cleaning a YG8 hard tungsten-cobalt alloy tool, followed by soft sandblasting, immersing the tool in a mixed solution under an inert atmosphere for ultrasonic treatment, removing the tool from the mixed solution for cleaning, and vacuum drying the tool at 80° C. to a constant weight to obtain a pretreated hard alloy tool;

[0046] 2) Under an inert atmosphere, place the pretreated carbide tool in a vacuum chamber, turn on the nitrogen gas source, and simultaneously turn on the AlCr composite target arc power supply and the TiZr alloy target power supply for deposition;

[0047] 3) Turn off all targets, bias power supply and gas source, keep the temperature at 372°C for 26 minutes, then cool down to below 100°C with the furnace, take out the tool, and cool it at room temperature to obtain a gradient coating.

[0048] In step 1), the soft sand blasting is performed at a pressure of 0.19 MPa for 28 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is performed at a temperature of 48°C and a power of 470 W for 38 seconds; the mixed solution comprises hydrochloric acid, oxalic acid, an auxiliary agent, and a solvent in a mass ratio of 41.5:27:6.8:1000; the solvent is a 20wt% ethanol aqueous solution; the auxiliary agent is a mixture of a thiophenol derivative and sodium lauryl sulfate in a mass ratio of 2.22:1.48; the preparation of the benzenethiol derivative comprises mixing protocatechuic aldehyde and anhydrous ethanol, adding m-aminothiophenol, stirring at a temperature of 58°C for 4.8 hours, and centrifuging to obtain the obtained product; the mass ratio of protocatechuic aldehyde, m-aminothiophenol, and anhydrous ethanol is 1.8:2.5:20.

[0049] In step 2), the parameters of the AlCr composite target arc power supply are 102A current, and the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 2.8A / min, and the tool substrate is treated for 150min; the working gas pressure in the vacuum chamber is 1.1Pa, and the bias voltage is 90V.

[0050] The thickness of the gradient coating is 150 nm, and the atomic percentage of each element in the gradient coating is: Al is 16.5 at.%, Cr is 9.8 at.%, Zr is 18.7 at.%, Ti is 10.675 at.%, and the rest is N element.

[0051] Example 5

[0052] A production process for cutting an AlCrTiXN coating for titanium alloy TC4 comprises the following steps:

[0053] 1) Degreasing, degreasing, and cleaning a YG8 hard tungsten-cobalt alloy tool, followed by soft sandblasting, immersing the tool in a mixed solution under an inert atmosphere for ultrasonic treatment, removing the tool from the mixed solution for cleaning, and vacuum drying the tool at 80° C. to a constant weight to obtain a pretreated hard alloy tool;

[0054] 2) Under an inert atmosphere, the pretreated carbide tool was placed in a vacuum chamber, the nitrogen gas source was turned on, and the arc power supply of the AlCr composite target and the power supply of the TiZr alloy target were turned on simultaneously for deposition treatment;

[0055] 3) Turn off all targets, bias power supply and gas source, keep the temperature at 380°C for 30 minutes, then cool down to below 100°C with the furnace, take out the tool, and cool at room temperature to obtain a gradient coating.

[0056] In step 1), the soft sand blasting is performed at a pressure of 0.20 MPa for 30 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is performed at a temperature of 50°C and a power of 500 W for 40 seconds; the mixed solution comprises hydrochloric acid, oxalic acid, an auxiliary agent, and a solvent in a mass ratio of 42:28:7.0:1000; the solvent is a 20wt% ethanol aqueous solution; the auxiliary agent is a mixture of a thiophenol derivative and sodium lauryl sulfate in a mass ratio of 2.3:1.5; the preparation of the benzenethiol derivative comprises mixing protocatechuic aldehyde and anhydrous ethanol, adding m-aminothiophenol, stirring at a temperature of 60°C for 5 hours, and centrifuging to obtain the obtained product; the mass ratio of protocatechuic aldehyde, m-aminothiophenol, and anhydrous ethanol is 1.8:2.5:20.

[0057] In step 2), the parameters of the AlCr composite target arc power supply are 120A current, the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 3A / min, and the tool substrate is treated for 150 minutes; the working gas pressure in the vacuum chamber is 1.2Pa, and the bias voltage is 100V.

[0058] The thickness of the gradient coating is 160 nm, and the atomic percentages of the elements in the gradient coating are: Al is 16.6 at.%, Cr is 10 at.%, Zr is 18.8 at.%, Ti is 10.68 at.%, and the rest is N element.

[0059] Comparative Example 1

[0060] Compared with Example 3, Comparative Example 1 is different in that sodium lauryl sulfate is not used, and the remaining components, preparation steps and parameters are the same.

[0061] Comparative Example 2

[0062] Compared with Example 3, Comparative Example 2 is different in that aniline replaces m-aminothiophenol, and the other components, preparation steps and parameters are the same.

[0063] Comparative Example 3

[0064] Compared with Example 3, Comparative Example 3 is different in that thiophenol replaces m-aminothiophenol, and the other components, preparation steps and parameters are the same.

[0065] Comparative Example 4

[0066] Compared with Example 3, Comparative Example 4 is different in that benzaldehyde replaces protocatechuic aldehyde, and the other components, preparation steps and parameters are the same.

[0067] Comparative Example 5

[0068] Compared with Example 3, Comparative Example 5 is different in that no benzenethiol derivative is used, and the remaining components, preparation steps and parameters are the same.

[0069] The tool coatings prepared in Examples 1-5 and Comparative Examples 1-5 were subjected to the following performance tests, and the test results are shown in Table 1.

[0070] Coating adhesion test: Use the file method and observe the coating morphology; according to GB / T5270-2005;

[0071] Hardness test: The hardness of the coating is tested according to ASTM-E-384;

[0072] Table 1

[0073] Coating bonding strength Hardness (HV) Example 1 The coating adhesion is qualified 3759 Example 2 The coating adhesion is qualified 3763 Example 3 The coating adhesion is qualified 3712 Example 4 The coating adhesion is qualified 3766 Example 5 The coating adhesion is qualified 3698 Comparative Example 1 Edge plating is peeling off 3267 Comparative Example 2 The coating is cracked and falling off 3361 Comparative Example 3 The coating is cracked and falling off 3106 Comparative Example 4 Edge plating is peeling off 3298 Comparative Example 5 The coating cracks and falls off severely 3009

[0074] From the test results in Table 1, it can be seen that compared with Comparative Examples 1-5, the coatings prepared in Examples 1-5 have excellent bonding strength with the cemented carbide tool substrate and have significant hardness performance.

[0075] The present invention can improve the etching effect of hydrofluoric acid through hydrochloric acid, and sodium dodecyl sulfate can reduce its surface tension, improve its wettability and permeability, and promote hydrofluoric acid to better contact and dissolve the surface oxide layer; the benzenethiol derivative contains a thiol group and an imine structure and forms a stable complex with metal ions, preventing the metal ions from being redeposited on the surface during the treatment process, thereby improving the removal effect of the oxide layer; it also contains a catechol structure with antioxidant properties, which can prevent the treated surface from being oxidized again and maintain the activity of the surface; the adsorption effect of the inhibitor and the metal can be enhanced through the synergistic effect of the imine structure, the thiol group and the catechol structure, and can also be adapted to the adsorption of various metals, reducing their oxidative corrosion, and providing protection for titanium alloy metals.

[0076] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A production process for AlCrTiXN coating for cutting titanium alloy TC4, characterized in that: The production process comprises the following steps: 1) Degreasing, degreasing, and cleaning the cemented carbide tool, blasting the tool with soft sand, immersing the tool in a mixed solution under an inert atmosphere, ultrasonically treating the tool, removing the tool from the mixed solution, cleaning the solution, and vacuum drying the solution to obtain a pretreated cemented carbide tool; 2) Under an inert atmosphere, place the pretreated carbide tool in a vacuum chamber, turn on the nitrogen gas source, and simultaneously turn on the ALCr composite target arc power supply and the TiZr alloy target power supply for deposition; 3) Turn off all targets, bias power supply and gas source, perform heat preservation treatment and then cool down with the furnace, take out the tool, cool at room temperature to obtain the gradient coating; Step 1) The mixed solution comprises hydrochloric acid, oxalic acid, sodium lauryl sulfate, a thiophenol derivative and a solvent, wherein the thiophenol derivative contains a sulfhydryl group, an imine structure and a catechol structure; Step 2) The parameters of the AlCr composite target arc power supply are 90-120A current, and the parameters of the TiZr alloy target power supply are 150A initial current and reduced at a rate of 2-3A / min, and the tool substrate is treated for 150 minutes.

2. The production process of an AlCrTiXN coating for cutting titanium alloy TC4 according to claim 1, characterized in that: In step 1), the carbide tool is a titanium alloy special milling cutter; the soft sand blasting is sand blasting at a pressure of 0.16-0.20 MPa for 24-30 minutes; the inert atmosphere is an Ar gas atmosphere; the ultrasonic treatment is ultrasonic treatment at a temperature of 40-50°C and a power of 400-500W for 30-40 seconds; and the vacuum drying is vacuum drying at a temperature of 80°C to constant weight.

3. The production process of an AlCrTiXN coating for cutting titanium alloy TC4 according to claim 1, characterized in that: In step 1), the mixed solution is composed of hydrochloric acid, oxalic acid, an auxiliary agent and a solvent in a mass ratio of 40-42:25-28:6.2-7.0:1000.

4. The production process of an AlCrTiXN coating for cutting titanium alloy TC4 according to claim 1, characterized in that: In step 2), the working gas pressure in the vacuum chamber is 0.8-1.2 Pa, and the bias voltage is 60-100V.

5. The production process of an AlCrTiXN coating for cutting titanium alloy TC4 according to claim 1, characterized in that: In step 3), the thickness of the gradient coating is 120-160 nm, and the atomic percentage of each element in the gradient coating is: Al is 16.2-16.6 at.%, Cr is 9.4-10 at.%, Zr is 18.5-18.8 at.%, Ti is 10.66-10.68 at.%, and the rest is N element.

6. The production process of an AlCrTiXN coating for cutting titanium alloy TC4 according to claim 1, characterized in that: In step 3), the heat preservation treatment is to keep the temperature at 350-380°C for 15-30 minutes, and the temperature reduction with the furnace is to reduce the temperature to below 100°C.