CN114752904A - High-temperature-resistant low-friction TiAlTaCN coating for cutting tool and preparation method thereof - Google Patents

High-temperature-resistant low-friction TiAlTaCN coating for cutting tool and preparation method thereof Download PDF

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CN114752904A
CN114752904A CN202210394605.8A CN202210394605A CN114752904A CN 114752904 A CN114752904 A CN 114752904A CN 202210394605 A CN202210394605 A CN 202210394605A CN 114752904 A CN114752904 A CN 114752904A
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coating
tialtacn
temperature
friction
substrate
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李国建
李显亮
吕汶璋
王凯
王强
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Northeastern University China
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Northeastern University China
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    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
    • C23C14/34—Sputtering
    • C23C14/35—Sputtering by application of a magnetic field, e.g. magnetron sputtering
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/0021—Reactive sputtering or evaporation
    • C23C14/0036—Reactive sputtering
    • C23C14/0057—Reactive sputtering using reactive gases other than O2, H2O, N2, NH3 or CH4
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/02—Pretreatment of the material to be coated
    • C23C14/021—Cleaning or etching treatments
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/02—Pretreatment of the material to be coated
    • C23C14/024—Deposition of sublayers, e.g. to promote adhesion of the coating
    • C23C14/025—Metallic sublayers
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/02—Pretreatment of the material to be coated
    • C23C14/028—Physical treatment to alter the texture of the substrate surface, e.g. grinding, polishing
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/0664—Carbonitrides
    • C—CHEMISTRY; METALLURGY
    • C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
    • C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
    • C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
    • C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
    • C23C14/14—Metallic material, boron or silicon
    • C23C14/16—Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon
    • C23C14/165—Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon by cathodic sputtering

Abstract

A high temperature resistant low friction TiAlTaCN coating for cutting tools and a preparation method thereof, the coating is composed of a priming layer and a working layer, the priming layer comprises Ti or TiAl, and the working layer comprises TiAlTaCN; the method comprises the following steps: (1) pretreatment of a substrate; (2) reverse cleaning; (3) preparing a priming coat; (4) preparing a working layer; (5) and (3) closing a sputtering power supply, stopping introducing gas, cooling the vacuum chamber along with the furnace until the temperature is less than or equal to 100 ℃, taking out the deposited substrate, naturally cooling to normal temperature, and preparing the TiAlTaCN coating on the substrate. The invention overcomes the problem that the existing coating can not simultaneously meet the requirements of low friction and high temperature resistance and oxidation resistance, and the prepared coating overcomes the problem that the multi-layer coating has complex process and high preparation cost, and has the advantages of simple process and low cost.

Description

High-temperature-resistant low-friction TiAlTaCN coating for cutting tool and preparation method thereof
Technical Field
The invention belongs to the technical field of materials, and particularly relates to a high-temperature-resistant low-friction TiAlTaCN coating for a cutting tool and a preparation method thereof.
Background
Modern machine manufacturing and cutting processing industries develop towards high speed, dry and green, increasingly higher requirements are put on surface coating materials of dies, cutters and cutting tools, and Physical Vapor Deposition (PVD) nano coatings with the characteristics of high hardness, high film-substrate binding force, high temperature resistance, oxidation resistance, low friction coefficient, high toughness and the like become one of hot spots of research in recent years. The coating applied in industry at present is mainly a binary and ternary coating of TiC, TiN, TiAlN and the like; the nitride coating cutter represented by TiAlN can obviously improve the cutting performance and prolong the service life of the cutter. However, when a material difficult to machine, such as a titanium alloy, is cut at a high speed, the coefficient of friction between the TiAlN coated tool and the titanium alloy is large (about 0.8), and a large amount of frictional heat is generated at the tip of the tool, which causes an excessively high local cutting temperature, aggravates a bonding failure, and reduces the tool life.
Amorphous C is an excellent solid lubricating material, and the element C is introduced into the TiAlN coating to form the TiAlCN coating which has the excellent wear resistance of TiAlN and can obviously reduce the friction coefficient and realize the effect of low friction coefficient; however, the hard alloy cutter is faced with high cutting force and vibration in the use process, particularly, the great friction loss and thermal shock influence (the processing temperature can reach more than 1000 ℃) exist between the cutting edge and a processed workpiece, while the oxidation resistance temperature of the TiAlCN coating is only 600 ℃, and the excessive cutting temperature can cause the failure of the cutter coating, the increase of adhesive wear and chemical wear, thereby directly influencing the quality of products and the service life of the cutter.
Therefore, in order to realize high-speed cutting of a material difficult to machine, it is necessary to develop a tool coating having high hardness, high wear resistance, good oxidation resistance, and a low friction coefficient.
Disclosure of Invention
The invention aims to provide a high-temperature-resistant low-friction TiAlTaCN coating for a cutting tool and a preparation method thereof, so that the coating has good high-temperature oxidation resistance and low friction coefficient, the performance of the cutting tool is improved, the abrasion loss of the cutting tool is reduced, the service life of the cutting tool is prolonged, the surface roughness of a workpiece is reduced, the process is simple, and the cost is low.
The high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is formed by compounding a priming layer and a working layer, wherein the priming layer comprises Ti or TiAl, and the working layer comprises TiAlTaCN.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool, the thickness of the priming layer is less than or equal to 500nm, and the thickness of the working layer is 2-4 mu m.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool, the working layer comprises 5-35% of Ti, 5-35% of Al, 2-35% of Ta, 10-60% of C and 10-60% of N in atomic percentage.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool, when the component of the priming coat is TiAl, the component of the priming coat contains 50% of Ti according to atomic percentage.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool, the priming layer and the working layer are sequentially deposited on the substrate.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool, the film-substrate binding force is more than or equal to 100N, the nano-hardness is 20-35 GPa, the friction coefficient is 0.2-0.3, and the oxidation resistance temperature is 800-1100 ℃.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool, the substrate is made of high-speed steel or hard alloy.
The high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool has the following component design principle: the binding force between the coating and the substrate is usually increased by Ti or TiAl and the like on the priming layer; al and Ta elements in the TiAlTaCN working layer can improve the high-temperature oxidation resistance of the coating, can also refine crystal grains, realize solid solution strengthening and improve the hardness of the coating, ensure the excellent wear resistance of the coating and can resist failure caused by temperature aggregation in the cutting process; the C element in the TiAlTaCN working layer can form an amorphous C lubricating phase, so that the friction coefficient of the coating is reduced, the lubricating and antifriction effects of the lubricating and antifriction effects not only reduce the cutting heat generated during cutting of the working layer of the coated cutter, but also prolong the cutting life of the cutter, and the problem that the existing nitride coating cannot have both low friction coefficient and high-temperature oxidation resistance is effectively solved; the invention can ensure the formation of the high-temperature resistant low-friction-coefficient cutter coating with high hardness, high wear resistance, good oxidation resistance and low friction coefficient through element content control.
The preparation method of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool comprises the following steps of:
(1) pretreatment of a matrix: firstly, grinding and polishing a substrate by using sand blasting equipment, and then carrying out ultrasonic cleaning on the substrate to obtain a cleaned substrate;
(2) reverse cleaning: putting the cleaning matrix into a vacuum chamber by adopting magnetron sputtering equipment; when the pressure of the vacuum chamber is less than or equal to 3 multiplied by 10-3When Pa is needed, heating to 250-550 ℃, continuously introducing high-purity argon into the vacuum chamber, and adjusting the pressure of the vacuum chamber to 0.5-2 Pa; then reversely cleaning for 10-45 min under the conditions of negative bias voltage of 500-1000V and duty ratio of 20-80%; after the reverse cleaning is finished, a reverse cleaning substrate is manufactured; stopping introducing high-purity argon, and vacuumizing until the pressure is less than or equal to 3 multiplied by 10-3Pa；
(3) Preparing a base layer: introducing high-purity argon again into the vacuum chamber to enable the pressure intensity in the vacuum chamber to be 0.3-0.9 Pa, controlling the temperature of the substrate to be 250-550 ℃, controlling the negative bias to be 20-180V, and controlling the duty ratio of the negative bias to be 20-80%; under the deposition condition, depositing for 4-6 min by adopting a pure titanium or titanium-aluminum alloy target material, and depositing on a reverse cleaning substrate to prepare a priming layer;
(4) preparing a working layer: stopping introducing high-purity argon after the bottom layer is prepared, and vacuumizing until the pressure is less than or equal to 3 multiplied by 10 -3Pa; then continuously introducing N into the vacuum chamber2And C2H2Continuously introducing high-purity argon into the mixed gas, controlling the pressure of a vacuum chamber to be 0.3-0.8 Pa, the temperature of the substrate to be 300-500 ℃, the negative bias to be 20-180V and the duty ratio of the negative bias to be 20-80 percent; under the deposition condition, a working layer is prepared on the priming layer by using a medium-frequency power sputtering TiAl alloy target and a direct-current power sputtering Ta target;
(5) and after the preparation of the working layer is finished, the sputtering power supply is closed, the gas is stopped to be introduced, the vacuum chamber is cooled along with the furnace until the temperature is less than or equal to 100 ℃, the vacuumizing is stopped, the deposited substrate is taken out and naturally cooled to the normal temperature, and the TiAlTaCN coating is prepared on the substrate.
In the step (1), the ultrasonic cleaning is sequentially carried out by respectively putting the raw materials into a cleaning agent, acetone and an alcohol solution, and then drying.
In the steps (2) and (3), the purity of the high-purity argon gas is 99.99%.
In the step (3), the purity of the pure titanium or the titanium-aluminum alloy is 99.9%.
In the step (3), when the titanium-aluminum alloy target material is adopted, the atomic ratio of aluminum to titanium in the titanium-aluminum alloy target material is 1: 1.
In the step (4), the purity of the high-purity argon gas is 99.99%.
In the above step (4), N 2And C2H2All the purities of (1) and (2) are 99.99%.
In the step (4), the partial pressure of acetylene is 5-10% of the total pressure, and the partial pressure of nitrogen is 20-40% of the total pressure.
In the step (4), the power for sputtering the TiAl alloy target by the medium-frequency power supply is 500-1500W, and the power for sputtering the Ta target by the direct-current power supply is 50-500W.
The invention has the following advantages and positive effects:
the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool comprises a Ti priming layer and a TiAlTaCN surface layer which are sequentially deposited on a substrate, wherein the TiAlTaCN surface layer is a tool coating with high hardness, high wear resistance, good oxidation resistance and low friction coefficient;
aiming at the defects that the existing cutter coating cannot have low friction coefficient and high-temperature oxidation resistance, the coating prepared by the invention has the characteristics of low friction coefficient, high hardness, excellent wear resistance, high-temperature oxidation resistance and the like, can realize high-speed processing of materials which are difficult to process, such as titanium alloy, stainless steel, high-temperature alloy and the like, and prolongs the service life of the cutter;
the invention overcomes the problem that the existing coating can not simultaneously meet the requirements of low friction and high temperature resistance and oxidation resistance, and the prepared coating overcomes the problem that the multi-layer coating has complex process and high preparation cost, and has the advantages of simple process and low cost; the prepared coating is suitable for cutting difficult-to-machine materials represented by titanium alloy, and has a very long service life, so that the machining requirement is met, the production cost is saved, and the production efficiency and the economic benefit are improved.
Drawings
FIG. 1 is a comparison graph of the results of the TiAlTaCN coating and TiAlCN coating bonding force tests of example 1 of the present invention; in the figure, (a)1) Indentation of TiAlCN coating, (a)2) Scratching the TiAlCN coating; (b)1) Is an indentation of the TiAlTaCN coating, (b)2) Scratching the TiAlTaCN coating;
FIG. 2 is a graph comparing the results of the coefficient of friction test and the frictional wear of a TiAlTaCN coating and a TiAlCN coating in an embodiment of the present invention; in the figure, the upper graph is the wear appearance of the TiAlCN coating, the lower graph is the wear appearance of the TiAlTaCN coating, the upper curve is the friction coefficient of the TiAlTaCN coating, and the lower curve is the friction coefficient of the TiAlCN coating;
FIG. 3 is a graph comparing hardness test results of a TiAlTaCN coating and a TiAlCN coating in an embodiment of the invention; in the figure, the hardness and elastic modulus of the TiAlCN coating are shown on the left, and the hardness and elastic modulus of the TiAlTaCN coating are shown on the right;
FIG. 4 is a graph comparing the results of 800 ℃ oxidation tests of TiAlTaCN coatings and TiAlCN coatings in an embodiment of the invention; in the figure, (a)1) Is the room temperature surface appearance of TiAlCN coating (a)2) Is the 800 ℃ surface appearance of the TiAlCN coating, (b)1) Is the surface appearance of the TiAlTaCN coating at room temperature, (b)2) Is the surface appearance of TiAlTaCN coating at 800 ℃, (c)1) Is the cross-sectional shape of the TiAlTaCN coating at room temperature, (c) 2) The TiAlTaCN coating has a section appearance at 800 ℃;
FIG. 5 is a graph comparing the results of high speed cutting length of TiAlTaCN and TiAlCN coated titanium alloys in the embodiment of the present invention; in the figure, ■ is a tool without coating, a tool with TiAlCN coating and a tool with TiAlTaCN coating.
Detailed Description
The cutter base body applicable to the method is made of materials which are conventional in the field, such as high-speed steel or hard alloy, or high-speed steel or hard alloy provided with polycrystalline cubic boron nitride, diamond or ceramic.
The coating preparation method is suitable for various physical vapor deposition devices including magnetron sputtering, multi-arc ion plating and the like, and is not limited to the magnetron sputtering device with the multi-target co-sputtering function.
The magnetron sputtering device adopted in the embodiment of the invention is commercially available.
In the embodiment of the invention, the standard used only for the binding force test is national standard JB/T8554-1997.
In the embodiment of the invention, reciprocating friction experimental equipment (MFT-4000, Lanzhou materialization institute) is selected for friction coefficient test and friction wear test, and reciprocating friction is carried out by applying load through a friction pair; the friction pair adopts a titanium ball with the diameter of 6mm, the load is 2N, the friction length is 5min, the friction speed is 50mm/min, and the friction time is 60 min.
In the embodiment of the invention, a nano-indenter (Agilent G200) is adopted to test the hardness and the elastic modulus of the coating, and the reference standard is JB/T12721-2016.
In the embodiment of the invention, the equipment for observing the morphology is a metallographic microscope (Olympus DSX 500).
The following detailed description is to be read with reference to the accompanying drawings and specific examples; the test methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
The cutter base body adopted in the embodiment of the invention is a hard alloy WC-10% Co cutter.
In the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool in the embodiment of the invention, the priming layer and the working layer are sequentially deposited on the substrate.
In the embodiment of the invention, the purity of the high-purity argon gas is 99.99%.
In the embodiment of the invention, the purity of the pure titanium or the titanium-aluminum alloy is 99.9%.
In the embodiment of the invention, when the titanium-aluminum alloy target material is adopted, the atomic ratio of aluminum to titanium in the titanium-aluminum alloy target material is 1: 1.
In the embodiment of the invention, N2And C2H2The purity of (A) was 99.99%.
In the embodiment of the invention, the power for sputtering the TiAl alloy target by the intermediate frequency power supply is 500-1500W, and the power for sputtering the Ta target by the direct current power supply is 50-500W.
The cleaning agent used in the examples of the present invention was a commercially available hard alloy cleaning agent (available under the trade name of anticorr plus cleaning agent (deconex, switzerland).
Example 1
The high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is formed by compounding a priming layer and a working layer, wherein the priming layer is TiAl, and the working layer is TiAlTaCN; the thickness of the bottom layer is 470nm, and the thickness of the working layer is 2 μm; the components of the working layer comprise 5 atomic percent of Ti, 35 atomic percent of Al, 18 atomic percent of Ta, 20 atomic percent of C and 22 atomic percent of N; the components of the bottom layer contain 50 percent of Ti according to atomic percentage;
the film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 130N, the nano hardness is 24GPa, the friction coefficient is 0.281, and the oxidation resistance temperature is 800 ℃;
the method comprises the following steps:
firstly, grinding and polishing a substrate by using sand blasting equipment, then sequentially putting the substrate into a cleaning agent, acetone and an alcohol solution for ultrasonic cleaning respectively, and drying the cleaned substrate to obtain a cleaned substrate;
putting the cleaning matrix into a vacuum chamber by adopting magnetron sputtering equipment; when the pressure of the vacuum chamber is less than or equal to 3 multiplied by 10-3When Pa is needed, the temperature is increased to 250 ℃, high-purity argon is continuously introduced into the vacuum chamber, and the pressure of the vacuum chamber is adjusted to be 0.5 Pa; then reversely cleaning for 10min under the conditions of negative bias voltage 500V and duty ratio of 20%; after the reverse cleaning is finished, a reverse cleaning substrate is manufactured; stopping introducing high-purity argon, and vacuumizing until the pressure is less than or equal to 3 multiplied by 10 -3Pa；
Introducing high-purity argon into the vacuum chamber again to ensure that the pressure in the vacuum chamber is 0.3Pa, controlling the temperature of the substrate to be 250 ℃, the negative bias to be 20V and the duty ratio of the negative bias to be 20 percent; under the deposition condition, depositing for 4min by adopting a titanium-aluminum alloy target material, and depositing on a reverse cleaning substrate to prepare a priming layer;
stopping introducing high-purity argon after the bottom layer is prepared, and vacuumizing until the pressure is less than or equal to 3 multiplied by 10-3Pa; then continuously introducing N into the vacuum chamber2And C2H2Mixing the gases, continuously introducing high-purity argon, and controlling the pressure of the vacuum chamber to be0.3Pa, the substrate temperature of 300 ℃, the negative bias of 20V and the negative bias duty ratio of 20 percent; under the deposition condition, a working layer is prepared on the priming layer by using a medium-frequency power sputtering TiAl alloy target and a direct-current power sputtering Ta target; wherein N is2And C2H2The flow rate of the mixed gas is 10-50 sccm, the partial pressure of acetylene is 5% of the total pressure, the partial pressure of nitrogen is 20% of the total pressure, and the flow rate of high-purity argon is 30-60 sccm;
after the preparation of the working layer is finished, a sputtering power supply is closed, gas is stopped to be introduced, the vacuum chamber is cooled along with the furnace until the temperature is less than or equal to 100 ℃, vacuumizing is stopped, the deposited substrate is taken out and naturally cooled to normal temperature, and a TiAlTaCN hard coating is prepared on the substrate;
Preparing a TiAlCN coating on the same substrate by the same method in a mode of not depositing Ta (a Ta target is not adopted when a working layer is prepared), and carrying out a comparative test; the results of the TiAlTaCN coating and TiAlCN coating binding force test are shown in figure 1, the results of the friction coefficient test and the frictional wear test are shown in figure 2, and the results of the hardness test are shown in figure 3; the two coatings are subjected to an oxidation test at 800 ℃, and the result is shown in fig. 4, the TiAlCN coating is completely oxidized at 600 ℃, and only 20% of the TiAlTaCN coating is partially oxidized at 800 ℃;
respectively carrying out a titanium alloy high-speed cutting test on a cutter without a coating, a TiAlCN coating cutter and a TiAlTaCN coating cutter, wherein the machining material is a titanium alloy with the model number of TC4, and the machining parameters are as follows: the turning speed is 100m/min, the feed rate is 0.02mm/r, and the cutting depth is 0.5 mm; under the same cutting parameter conditions, the test results are shown in fig. 5; according to experimental results, under the same conditions, the titanium alloy of TC4 is turned, the turning length of the TiAlTaCN coating hard alloy cutter reaches 2100m, the TiAlCN coating cutter only turns 600m, and the service life of the TiAlTaCN coating cutter is greatly prolonged.
Example 2
The difference between the high temperature resistant low friction TiAlTaCN coating for the cutting tool and the example 1 is that:
(1) The thickness of the bottom layer is 420nm, and the thickness of the working layer is 3 mu m; the components of the working layer comprise 35 percent of Ti, 5 percent of Al, 35 percent of Ta, 10 percent of C and 15 percent of N in atomic percentage;
(2) the film base binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 135N, the nano hardness is 26GPa, the friction coefficient is 0.247, and the oxidation resistance temperature is 900 ℃;
the method is the same as example 1, except that:
(1) heating to 550 ℃; adjusting the pressure of the vacuum chamber to 2 Pa; reversely cleaning for 15min under the conditions of negative bias 600V and duty ratio of 30%;
(2) introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.4Pa, controlling the temperature of the substrate to be 550 ℃, controlling the negative bias to be 40V and keeping the negative bias duty ratio to be 25 percent; depositing for 5 min;
(3) controlling the pressure intensity of the vacuum chamber to be 0.4Pa, the substrate temperature to be 350 ℃, the negative bias to be 40V and the negative bias duty ratio to be 25 percent; the partial pressure of acetylene was 6% of the total pressure and the partial pressure of nitrogen was 22% of the total pressure.
Example 3
The difference between the high temperature resistant low friction TiAlTaCN coating for the cutting tool and the example 1 is that:
(1) the thickness of the bottom layer is 450nm, and the thickness of the working layer is 4 μm; the components of the working layer comprise 30 percent of Ti, 20 percent of Al, 2 percent of Ta, 38 percent of C and 10 percent of N in atomic percentage;
(2) The film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 125N, the nano hardness is 22GPa, the friction coefficient is 0.258, and the oxidation resistance temperature is 1000 ℃;
the method is the same as example 1, except that:
(1) heating to 350 ℃; adjusting the pressure of the vacuum chamber to 1 Pa; reversely washing for 20min under the conditions of negative bias voltage of 700V and duty ratio of 40%;
(2) introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.5Pa, controlling the temperature of the substrate to be 350 ℃, the negative bias to be 60V and the duty ratio of the negative bias to be 30 percent; depositing for 6 min;
(3) controlling the pressure of a vacuum chamber to be 0.5Pa, the temperature of the substrate to be 400 ℃, the negative bias to be 60V and the duty ratio of the negative bias to be 30 percent; the partial pressure of acetylene was 7% of the total pressure and the partial pressure of nitrogen was 24% of the total pressure.
Example 4
The difference between the high temperature resistant low friction TiAlTaCN coating for the cutting tool and the example 1 is that:
(1) the bottom layer comprises Ti, the thickness of the bottom layer is 460nm, and the thickness of the working layer is 2.5 mu m; the components of the working layer comprise 8 percent of Ti, 7 percent of Al, 5 percent of Ta, 60 percent of C and 20 percent of N in atomic percentage;
(2) the film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 140N, the nano hardness is 29GPa, the friction coefficient is 0.277, and the oxidation resistance temperature is 1100 ℃;
The method is the same as example 1, except that:
(1) heating to 450 ℃; adjusting the pressure of the vacuum chamber to 1.5 Pa; reversely cleaning for 25min under the conditions of negative bias 800V and duty ratio of 50%;
(2) adopting a pure titanium target material, introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.6Pa, controlling the temperature of the substrate to be 450 ℃, the negative bias to be 80V and the negative bias duty ratio to be 40 percent; depositing for 4.5 min;
(3) controlling the pressure intensity of the vacuum chamber to be 0.6Pa, the substrate temperature to be 450 ℃, the negative bias to be 80V and the negative bias duty ratio to be 40 percent; the partial pressure of acetylene was 8% of the total pressure and the partial pressure of nitrogen was 26% of the total pressure.
Example 5
The difference between the high temperature resistant low friction TiAlTaCN coating for the cutting tool and the example 1 is that:
(1) the thickness of the bottom layer is 430nm, and the thickness of the working layer is 3.5 mu m; the components of the working layer comprise 6 percent of Ti, 8 percent of Al, 14 percent of Ta, 12 percent of C and 60 percent of N in atomic percentage;
(2) the film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 125N, the nano hardness is 31GPa, the friction coefficient is 0.296, and the oxidation resistance temperature is 1000 ℃;
the method is the same as example 1, except that:
(1) heating to 300 ℃; adjusting the pressure of the vacuum chamber to 1 Pa; reversely cleaning for 30min under the conditions of negative bias voltage of 900V and duty ratio of 60%;
(2) Introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.7Pa, controlling the temperature of the substrate to be 300 ℃, the negative bias to be 100V and the duty ratio of the negative bias to be 50 percent; depositing for 5.5 min;
(3) controlling the pressure of a vacuum chamber to be 0.7Pa, the temperature of the substrate to be 500 ℃, the negative bias to be 100V and the duty ratio of the negative bias to be 50 percent; the partial pressure of acetylene was 10% of the total pressure and the partial pressure of nitrogen was 28% of the total pressure.
Example 6
The difference between the high temperature resistant low friction TiAlTaCN coating for the cutting tool and the example 1 is that:
(1) the thickness of the bottom layer is 410nm, and the thickness of the working layer is 2.8 mu m; the components of the working layer comprise 10 percent of Ti, 10 percent of Al, 20 percent of Ta, 15 percent of C and 45 percent of N in atomic percentage;
(2) the film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 135N, the nano hardness is 29GPa, the friction coefficient is 0.229, and the oxidation resistance temperature is 900 ℃;
the method is the same as example 1, except that:
(1) heating to 400 ℃; adjusting the pressure of the vacuum chamber to 1.5 Pa; under the conditions of negative bias 1000V and duty ratio of 70%, reversely cleaning for 35 min;
(2) introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.8Pa, controlling the temperature of the substrate to be 400 ℃, the negative bias to be 120V and the duty ratio of the negative bias to be 60 percent; depositing for 5 min;
(3) Controlling the pressure of the vacuum chamber to be 0.8Pa, the temperature of the substrate to be 450 ℃, the negative bias to be 120V and the duty ratio of the negative bias to be 60 percent; the partial pressure of acetylene was 9% of the total pressure and the partial pressure of nitrogen was 30% of the total pressure.
Example 7
The difference between the high temperature resistant low friction TiAlTaCN coating for cutting tools and the example 1 is that:
(1) the bottom layer is made of Ti, the thickness of the bottom layer is 440nm, and the thickness of the working layer is 3.2 mu m; the components of the working layer comprise 14 atomic percent of Ti, 12 atomic percent of Al, 17 atomic percent of Ta, 35 atomic percent of C and 22 atomic percent of N;
(2) the film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 140N, the nano hardness is 35GPa, the friction coefficient is 0.267, and the oxidation resistance temperature is 1000 ℃;
the method is the same as example 1, except that:
(1) heating to 500 ℃; adjusting the pressure of the vacuum chamber to 2 Pa; reversely cleaning for 40min under the conditions of negative bias voltage of 900V and duty ratio of 80%;
(2) adopting a pure titanium target material, introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.9Pa, controlling the temperature of the substrate to be 500 ℃, controlling the negative bias to be 150V and controlling the duty ratio of the negative bias to be 70 percent; depositing for 6 min;
(3) controlling the pressure intensity of the vacuum chamber to be 0.7Pa, the substrate temperature to be 400 ℃, the negative bias to be 150V and the negative bias duty ratio to be 70 percent; the partial pressure of acetylene was 8% of the total pressure and the partial pressure of nitrogen was 35% of the total pressure.
Example 8
The difference between the high temperature resistant low friction TiAlTaCN coating for the cutting tool and the example 1 is that:
(1) the thickness of the bottom layer is 490nm, and the thickness of the working layer is 3.6 μm; the components of the working layer comprise 15 percent of Ti, 15 percent of Al, 12 percent of Ta, 40 percent of C and 18 percent of N in atomic percentage;
(2) the film-substrate binding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is 135N, the nano hardness is 28GPa, the friction coefficient is 0.256, and the oxidation resistance temperature is 1100 ℃;
the method is the same as example 1, except that:
(1) heating to 550 ℃; adjusting the pressure of the vacuum chamber to 2 Pa; reversely cleaning for 45min under the conditions of negative bias 800V and duty ratio of 50%;
(2) introducing high-purity argon again to ensure that the pressure in the vacuum chamber is 0.8Pa, controlling the temperature of the substrate to be 550 ℃, the negative bias to be 180V and the duty ratio of the negative bias to be 80 percent; depositing for 5.5 min;
(3) controlling the pressure intensity of the vacuum chamber to be 0.6Pa, the substrate temperature to be 350 ℃, the negative bias to be 180V and the negative bias duty ratio to be 80 percent; the partial pressure of acetylene was 7% of the total pressure and the partial pressure of nitrogen was 40% of the total pressure.
The present invention is not limited to the above embodiments, and various changes may be made to the present invention within the scope of the claims and their equivalents.

Claims (10)

1. A high-temperature-resistant low-friction TiAlTaCN coating for a cutting tool is formed by compounding a priming coat and a working layer, and is characterized in that: the bottom layer is made of Ti or TiAl, and the working layer is made of TiAlTaCN.
2. The high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool as claimed in claim 1, wherein the thickness of the primer layer is less than or equal to 500nm, and the thickness of the working layer is 2-4 μm.
3. The high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool as claimed in claim 1, wherein the working layer comprises 5-35% of Ti, 5-35% of Al, 2-35% of Ta, 10-60% of C and 10-60% of N by atomic percentage.
4. The high temperature resistant low friction TiAlTaCN coating for a cutting tool according to claim 1, wherein when the composition of the primer layer is TiAl, the composition of the primer layer comprises 50 atomic percent of Ti.
5. The high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool as claimed in claim 1, wherein the film-based bonding force of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool is not less than 100N, the nano hardness is 20-35 GPa, the friction coefficient is 0.2-0.3, and the oxidation resistance temperature is 800-1100 ℃.
6. The preparation method of the high-temperature-resistant low-friction TiAlTaCN coating for the cutting tool as claimed in claim 1, which is characterized by comprising the following steps:
(1) Pretreatment of a matrix: firstly, grinding and polishing a substrate by adopting sand blasting equipment, and then carrying out ultrasonic cleaning on the substrate to obtain a cleaned substrate;
(2) reverse cleaning: putting the cleaning matrix into a vacuum chamber by adopting magnetron sputtering equipment; when the pressure of the vacuum chamber is less than or equal to 3 multiplied by 10- 3When Pa is needed, the temperature is increased to 250-550 ℃, and the vacuum is turned to vacuumContinuously introducing high-purity argon into the chamber, and adjusting the pressure of the vacuum chamber to be 0.5-2 Pa; then reversely cleaning for 10-45 min under the conditions of negative bias voltage of 500-1000V and duty ratio of 20-80%; after the reverse cleaning is finished, a reverse cleaning substrate is manufactured; stopping introducing high-purity argon, and vacuumizing until the pressure is less than or equal to 3 multiplied by 10-3Pa；
(3) Preparing a base layer: introducing high-purity argon again into the vacuum chamber to enable the pressure intensity in the vacuum chamber to be 0.3-0.9 Pa, controlling the temperature of the substrate to be 250-550 ℃, controlling the negative bias to be 20-180V, and controlling the duty ratio of the negative bias to be 20-80%; under the deposition condition, depositing for 4-6 min by adopting a pure titanium or titanium-aluminum alloy target material, and depositing on a reverse cleaning substrate to prepare a priming layer;
(4) preparing a working layer: stopping introducing high-purity argon after the bottom layer is prepared, and vacuumizing until the pressure is less than or equal to 3 multiplied by 10-3Pa; then continuously introducing N into the vacuum chamber2And C2H2Continuously introducing high-purity argon into the mixed gas, controlling the pressure of a vacuum chamber to be 0.3-0.8 Pa, the temperature of the substrate to be 300-500 ℃, the negative bias to be 20-180V and the duty ratio of the negative bias to be 20-80 percent; under the deposition condition, a working layer is prepared on the priming layer by using a medium-frequency power sputtering TiAl alloy target and a direct-current power sputtering Ta target;
(5) And after the preparation of the working layer is finished, the sputtering power supply is closed, the gas is stopped to be introduced, the vacuum chamber is cooled along with the furnace until the temperature is less than or equal to 100 ℃, the vacuumizing is stopped, the substrate after the deposition is finished is taken out and naturally cooled to the normal temperature, and the TiAlTaCN coating is prepared on the substrate.
7. The method for preparing the TiAlTaCN coating with high temperature resistance and low friction for the cutting tool according to claim 6, wherein in the step (4), N is2And C2H2All the purities of (1) and (2) are 99.99%.
8. The method for preparing the high temperature resistant low friction TiAlTaCN coating for the cutting tool according to claim 6, wherein in the step (4), the partial pressure of acetylene is 5-10% of the total pressure, and the partial pressure of nitrogen is 20-40% of the total pressure.
9. The method for preparing the high temperature resistant low friction TiAlTaCN coating for the cutting tool according to claim 6, wherein in the step (4), the purity of the high purity argon gas is 99.99%.
10. The method for preparing the high temperature resistant low friction TiAlTaCN coating for the cutting tool according to claim 6, wherein in the step (4), the power for sputtering the TiAl alloy target by the medium frequency power supply is 500-1500W, and the power for sputtering the Ta target by the direct current power supply is 50-500W.
CN202210394605.8A 2022-04-15 2022-04-15 High-temperature-resistant low-friction TiAlTaCN coating for cutting tool and preparation method thereof Pending CN114752904A (en)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020081161A1 (en) * 2000-10-31 2002-06-27 Mmc Kobelco Tool Co., Ltd. High-speed tool steel gear cutting tool and manufacturing method therefor
US20090269614A1 (en) * 2008-04-24 2009-10-29 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) Hard coating film and target for formation thereof
CN107201499A (en) * 2017-05-26 2017-09-26 东北大学 A kind of titanium alloy cutting component gradient TiAlXN coated cutting tools and preparation method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20020081161A1 (en) * 2000-10-31 2002-06-27 Mmc Kobelco Tool Co., Ltd. High-speed tool steel gear cutting tool and manufacturing method therefor
US20090269614A1 (en) * 2008-04-24 2009-10-29 Kabushiki Kaisha Kobe Seiko Sho (Kobe Steel, Ltd.) Hard coating film and target for formation thereof
CN107201499A (en) * 2017-05-26 2017-09-26 东北大学 A kind of titanium alloy cutting component gradient TiAlXN coated cutting tools and preparation method thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
XUDONG SUI ET AL.: "Effect of Ta content on microstructure, hardness and oxidation resistance of TiAlTaN coatings", 《INTERNATIONAL JOURNAL OF REFRACTORY METALS AND HARD MATERIALS》 *
XUHAI ZHANG ET AL.: "Effect of carbon on TiAlCN coatings deposited by reactive magnetron sputtering", 《SURFACE & COATINGS TECHNOLOGY》 *

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