High-temperature wear-resistant coated cutting tool and preparation method thereof

Abstract

The invention relates to the technical field of coated cutting tools, and provides a high-temperature wear-resistant coated cutting tool and a preparation method thereof.The high-temperature wear-resistant coated cutting tool comprises a base body and a high-temperature wear-resistant coating, and the base body is coated with the high-temperature wear-resistant coating; the matrix is a WC-based hard alloy; the coating comprises a WaAlbSicB2 bonding layer and a Ti < x > Al < y > Si < z > B2 functional layer from inside to outside, wherein the Ti < x > Al < y > Si < z > B < 2 > functional layer is of a columnar crystal layer-equiaxed crystal layer alternating structure and has a grain size, amorphous phase proportion and Al / Si element triple gradient structure in the thickness direction. A double-peak structure design is adopted in the matrix, namely coarse-grain WC constructs a framework, fine-grain WC fills gaps, and the strength and the toughness are synergistically improved through the double-peak structure design; and meanwhile, the micro-texture array is arranged on the surface of the substrate, so that the coating and the substrate form mechanical interlocking, and the film-substrate bonding strength is remarkably enhanced. The cutter has good wear resistance, good toughness, excellent film-substrate bonding strength and good high-temperature oxidation resistance, and is suitable for high-speed cutting of difficult-to-machine materials such as titanium alloy and nickel-based high-temperature alloy.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of coated cutting tools, and particularly relates to a high-temperature wear-resistant coated cutting tool and a preparation method thereof. BACKGROUND

[0002] The rapid development of the aerospace field has driven the demand for high-performance materials, among which titanium alloys and high-temperature alloys have become key materials in extreme service environments due to their excellent specific strength, high-temperature strength and corrosion resistance. However, the characteristics of these materials, especially high strength and low thermal conductivity, have brought significant challenges to their cutting processing. When a coated cutting tool is used to machine titanium alloys or high-temperature alloys, the high hardness of the workpiece material leads to severe tool wear. Under the conditions of high-speed cutting or heavy-load cutting, extremely high frictional stress and thermal stress are generated in the tool-workpiece contact area, accelerating the wear of the coating and significantly shortening the tool life. What is particularly critical is that the low thermal conductivity of titanium alloys and high-temperature alloys hinders the effective diffusion of cutting heat generated during processing, resulting in a sharp rise in temperature in the cutting zone. High temperature not only softens the coating material, reduces its hardness and strength, and weakens the cutting performance, but also easily induces the adhesion of the workpiece material to the rake face of the tool (tool sticking), which seriously affects the surface quality and dimensional accuracy of the machining. Under the coupling action of high temperature, high mechanical stress and high cutting speed, the coating is prone to brittle spalling or micro-crack propagation, further exacerbating tool failure.

[0003] Therefore, it is crucial to develop cutting tools that combine excellent wear resistance, toughness, superior film-substrate bonding strength, and high-temperature oxidation resistance. Physical vapor deposition (PVD) technology has become a key method for preparing cutting tool coatings due to its relatively low deposition temperature and minimal impact on the mechanical properties of the tool substrate. AlTiN, one of the most widely used coatings, is renowned for its excellent wear resistance, high-temperature stability (due to the dense Al2O3 oxide layer formed at high temperatures), and chemical stability. However, when cutting titanium alloys, its poor adhesion resistance can lead to chip accumulation on the rake face, forming a built-up edge (BUE). Unstable BUE growth and shedding damage the machined surface, causing cutting force fluctuations, accelerated tool wear, and even chipping. AlCrN coatings offer outstanding high-temperature oxidation resistance, but under sustained high-temperature cutting conditions (typically >800°C), they decompose, forming lower-hardness CrN and AlN phases. This phase transformation significantly reduces the coating's macroscopic hardness and, consequently, degrades its wear resistance, making it difficult to meet the requirements for long-life, stable cutting of difficult-to-cut materials such as high-temperature alloys. TiSiN is a typical nanocomposite coating, composed of nanocrystalline TiN particles dispersed within an amorphous Si3N4 matrix. This structure imparts ultrahigh hardness (typically >40 GPa) and excellent high-temperature stability to the coating (the Si3N4 matrix effectively inhibits grain coarsening and oxidation). However, the presence of the amorphous phase reduces the coating's toughness, making it less resistant to chipping under intermittent cutting or mechanical impact, and susceptible to micro- or macro-failure. TiB2 coatings offer an extremely low coefficient of friction and a smooth surface, effectively reducing frictional heat and cutting forces during cutting. However, their primary drawback is poor oxidation resistance. In high-temperature, oxygen-containing environments, they readily oxidize to form B2O3 and TiO2, leading to coating performance degradation. Furthermore, TiB2 coatings lack inherent toughness, making them susceptible to chipping under heavy loads or intermittent cutting. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention aims to provide a high-temperature wear-resistant coating tool and a preparation method thereof.

[0005] According to the first aspect of the present invention, the present invention provides the following technical solutions: A high-temperature wear-resistant coating tool, comprising: A substrate and a high-temperature wear-resistant coating applied on the substrate; The substrate is WC-based cemented carbide; the high-temperature wear-resistant coating is prepared by physical vapor deposition method, and the high-temperature wear-resistant coating includes WC from the inside to the outside. a Al b Si c B2 bonding layer and Ti x Al y Si zB2 functional layer; wherein a+b+c=1, x+y+z=1.

[0006] As a preferred scheme of the high-temperature wear-resistant coating cutter, Ti x Al y Si z B2 functional layer contains Ti x1 Al y1 Si z1 B2 columnar crystal layer and Ti x2 Al y2 Si z2 B2 equiaxed crystal layer, wherein x1+y1+z1=1, x2+y2+z2=1, and the two are alternately deposited with an alternating period of 2-4 times.

[0007] As a preferred scheme of the high-temperature wear-resistant coating cutter, Ti x2 Al y2 Si z2 B2 equiaxed crystal layer is amorphous Si wrapped (Ti, Al) B2 nano equiaxed crystal; Ti x1 Al y1 Si z1 B2 columnar crystal layer is amorphous Si wrapped (Ti, Al) B2 nanocolumnar crystal.

[0008] As a preferred scheme of the high-temperature wear-resistant coating cutter, Ti x2 Al y2 Si z2 B2 equiaxed crystal layer has a gradient structure along its thickness growth direction, including: (a) Grain size gradient: the average size of the crystal grains continuously decreases from the substrate to the surface of the coating, with a variation amplitude of 40-50 nm; (b) Amorphous phase proportion gradient: the area proportion of the amorphous phase region continuously increases from the substrate to the surface of the coating, with a variation amplitude of 30-50%; (c) Element composition gradient: the atomic percentage of Al element continuously decreases from the substrate to the surface of the coating, with a variation amplitude of 1-2 at%; at the same time, the atomic percentage of Si element continuously increases from the substrate to the surface of the coating, with a variation amplitude of 2-3 at%.

[0009] As a preferred scheme of the high-temperature wear-resistant coating cutter, Ti x1 Al y1 Si z1 B2 columnar crystal layer has a gradient structure along its thickness growth direction, including: (a) Amorphous phase proportion gradient: the area proportion of the amorphous phase region continuously increases from the substrate to the surface of the coating, with a variation amplitude of 20-40%; (b) element composition gradient: the atomic percentage of Al continuously decreases from the substrate to the surface of the coating, with a variation of 1.5-2.5 at%; meanwhile, the atomic percentage of Si continuously increases from the substrate to the surface of the coating, with a variation of 1.5-2.5 at%.

[0010] As a preferred scheme of the high-temperature wear-resistant coating tool according to the application, in the formula, Ti x2 Al y2 Si z2 In the B2 equiaxed crystal layer, the content of Si is 6-10 at%, the content of Al is 2-5 at%, and the atomic ratio of metal elements to B elements is 0.38≤(Ti+Al) / B≤0.42.

[0011] As a preferred scheme of the high-temperature wear-resistant coating tool according to the application, in the formula, Ti x1 Al y1 Si z1 In the B2 columnar crystal layer, the content of Si is 2-5.5 at%, the content of Al is 3-6 at%, and the atomic ratio of metal elements to B elements is 0.42≤(Ti+Al) / B≤0.48.

[0012] As a preferred scheme of the high-temperature wear-resistant coating tool according to the application, in the formula, W a Al b Si c The thickness of the B2 adhesive layer is 0.1-0.2 μm; Ti x Al y Si z The thickness of the B2 functional layer is 3.0-6.0 μm; Ti x2 Al y2 Si z2 The thickness of the B2 equiaxed crystal layer is 0.5-1.2 μm; Ti x1 Al y1 Si z1 The thickness of the B2 columnar crystal layer is 0.5-1.2 μm; and the total thickness of the high-temperature wear-resistant coating is 3.1-6.2 μm.

[0013] As a preferred scheme of the high-temperature wear-resistant coating tool according to the application, in the formula, W a Al b Si c The B2 adhesive layer is amorphous Si wrapped (W, Al)B2 nanometer columnar crystals.

[0014] As a preferred scheme of the high-temperature wear-resistant coating tool, the substrate comprises 7.0-10.0 wt% of Co, 1.0-2.0 wt% of Ni, and the balance of WC phase; the WC phase comprises coarse-grained WC with a grain size of 0.8-1.4 μm and fine-grained WC with a grain size of 0.3-0.6 μm, and the fine-grained WC exists in the gap between the coarse-grained WC; the volume fraction of the coarse-grained WC accounts for 70-80%, and the volume fraction of the fine-grained WC accounts for 20-30%.

[0015] As a preferred scheme of the high-temperature wear-resistant coating tool, the substrate surface is provided with a micro-texture array with a depth of 3.5-7 μm and a characteristic size of 30-100 μm, and the distance between adjacent micro-textures is 1.5-3 times the characteristic size; the high-temperature wear-resistant coating is deposited to fill the micro-texture to form a mechanical anchoring structure, and the deposition profile is consistent with the micro-texture morphology with a degree of ≥95%, and the anchoring depth is ≥85% of the micro-texture depth.

[0016] As a preferred scheme of the high-temperature wear-resistant coating tool, the hardness of the substrate is 1300-1500 HV, and the fracture toughness is ≥18 MPa·m 1 / 2 .

[0017] According to the second aspect of the present application, the present application provides the following technical scheme: A preparation method of the above-mentioned high-temperature wear-resistant coating tool, the coating is prepared by a high-power pulse magnetron sputtering process, comprising the following steps: S1, depositing W a Al b Si c B2 binder layer, the process parameters are as follows: The temperature is 600-800 ℃, the bias voltage is -70--120 V, the sputtering power of the WB2 target is 4-6 kW, the sputtering power of the Al target is 1-2 kW, the sputtering power of the Si target is 0.5-3 kW, and the gas pressure is 0.2-1.0 Pa, wherein the gas is pure Ar; S2, depositing Ti a Al b Si c B2 on the surface of the W x Al y Si z B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, the process parameters are as follows: The temperature is 600~800℃, the sputtering power of TiB2 target is 4~6kW, the sputtering power of Al target is 0.5~2kW, the sputtering power of Si target is 0.5~2kW, the gas pressure is 0.2~1.0Pa, and the gas is pure Ar; Ti x1 Al y1 Si z1 During the deposition of the B2 columnar crystal layer, the bias voltage increased linearly from -60 V to -70~-120 V; the sputtering power of the Al target decreased linearly from 2 kW to 0.5 kW; the sputtering power of the Si target increased linearly from 0.5 kW to 2 kW. S3, in Ti x1 Al y1 Si z1 Ti is deposited on the surface of B2 columnar crystal layer x Al y Si z Ti in the B2 functional layer x2 Al y2 Si z2 B2 equiaxed crystal layer, process parameters are: The temperature is 600~800℃, the bias voltage is -70~-120V, the sputtering power of TiB2 target is 4~8kW, the sputtering power of Al target is 0.5~1.5kW, the sputtering power of Si target is 2~4kW, the gas pressure is 0.2~1.0Pa, and the gas is pure Ar; Ti x2 Al y2 Si z2 During the deposition of the B2 equiaxed crystal layer, the sputtering power of the Al target decreased linearly from 1.5kW to 0.5kW; the sputtering power of the Si target increased linearly from 2kW to 4kW. S4, steps S2 and S3 are alternately deposited, with a cycle of 2 to 4 times; S5. After the temperature drops to room temperature, take out the sample to obtain a high-temperature wear-resistant coating tool.

[0018] As a preferred embodiment of the method for preparing a high-temperature wear-resistant coating tool according to the present invention, the method further comprises: S0. Pretreatment: Using carbide cutting tools as substrates, the substrates are sandblasted, cleaned, and dried before being placed on a rotating rack. The surface of the substrates is then glow-discharge cleaned.

[0019] The beneficial effects of the present invention are as follows: The present invention provides a high-temperature wear-resistant coating tool and a preparation method thereof. The tool comprises a substrate and a high-temperature wear-resistant coating coated on the substrate; the substrate is a WC-based cemented carbide; the coating comprises WC from the inside out. a Al b Si cB2 bonding layer and Ti x Al y Si z B2 functional layer; Ti x Al y Si z The B2 functional layer exhibits an alternating structure of "columnar crystal layers and equiaxed crystal layers," and possesses a triple gradient structure of grain size, amorphous phase ratio, and Al / Si elements in the thickness direction. A bimodal microstructure design is employed within the substrate, with coarse-grained WC forming the skeleton and fine-grained WC filling the gaps. This bimodal microstructure design synergistically enhances strength and toughness. At the same time, a micro-texture array is provided on the substrate surface, mechanically interlocking the coating and substrate, significantly enhancing the film-substrate bonding strength. This tool combines good wear resistance, good toughness, excellent film-substrate bonding strength, and good resistance to high-temperature oxidation, making it suitable for high-speed cutting of difficult-to-machine materials such as titanium alloys and nickel-based high-temperature alloys. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0021] Figure 1 It is a schematic cross-sectional view of the high-temperature wear-resistant coating tool of the present invention.

[0022] In the figure, 100-matrix; 200-W a Al b Si c B2 bonding layer; 300-Ti x Al y Si z B2 functional layer; 310-Ti x1 Al y1 Si z1 B2 columnar crystal layer; 320- Ti x2 Al y2 Si z2 B2 equiaxed crystal layer.

[0023] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0024] The following will be a clear and complete description of the technical solutions in the embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0025] The present invention provides a high-temperature wear-resistant coating tool and a preparation method thereof, wherein the tool comprises: A substrate 100 and a high-temperature wear-resistant coating applied on the substrate 100; The substrate 100 is a WC-based cemented carbide; the high-temperature wear-resistant coating is prepared by physical vapor deposition, and the high-temperature wear-resistant coating includes WC from the inside to the outside. a Al b Si c B2 bonding layer 200 and Ti x Al y Si z B2 functional layer 300. Ti x Al y Si z The B2 functional layer 300 includes Ti x1 Al y1 Si z1 B2 columnar crystal layer 310 and Ti x2 Al y2 Si z2 The B2 equiaxed crystal layer 320 is deposited alternately, with an alternating cycle of 2 to 4 times. The high-temperature wear-resistant coating tool of the present invention has good wear resistance, good toughness, excellent film-base bonding strength, and good resistance to high-temperature oxidation. The specific features are as follows: (1) In the present invention, micro-texturing of the substrate surface can effectively improve the film-substrate bonding strength and also improve the cutting life of the tool during the cutting process. a Al b Si c B2 bonding layer, located between the substrate and Ti x Al y Si z The B2 functional layer has good bonding properties to both, thus significantly enhancing the bonding strength between the functional layer and the substrate. During the high temperature cutting process, the W element in the substrate and the W a Al b Si c The W element in the B2 bonding layer has a strong affinity and is easy to diffuse with each other, thus improving the bonding strength between the membrane and the substrate. a Al b Si c The Al, Si, and B elements in the B2 bonding layer can react with Tix Al y Si z B2 functional layer, mutual diffusion is easy to occur, thereby improving the binding force between the coating layers. a Al b Si c B2 adhesive layer can also act as an epitaxial growth template for the Ti x Al y Si z B2 functional layer, so that the Ti x Al y Si z B2 functional layer grows into the desired structure. In addition, due to the design of the composition gradient structure, in the Ti x Al y Si z B2 functional layer, there is an over-interval between the columnar crystals and the equiaxed crystals, so there is no obvious coating delamination interface between the two, and compared with other multilayer coatings, the coating has better binding force.

[0026] (2) In the present application, the incorporation of Si exists in the coating in an amorphous state, and the proportion of the amorphous phase increases with the increase of the Si content. By controlling the incorporation of Si content, the amorphous phase exists everywhere in the Ti x Al y Si z B2 functional layer, reducing the defects in the coating, and at the same time, can hinder the gas from entering the coating, which will further improve the mechanical properties, oxidation resistance and high-temperature stability of the coating. In addition, by adjusting the content of Si, the structure and morphology of the crystals in the coating can be changed, thereby realizing the complex multi-scale structure inside the coating. The incorporation of Al element can form (Al, Ti) B2 solid solution with TiB2, thereby improving the hardness, toughness and high-temperature oxidation resistance of the coating.

[0027] (3) In the present application, for the columnar crystal layer in the Ti x Al y Si z B2 functional layer, the use of gradient bias can make the overall structure of the columnar crystal consistent, thereby improving the performance of the coating; and the introduction of Al element content gradient structure in the columnar crystal layer can strengthen the hardness of the coating while ensuring the toughness of the coating basically unchanged.

[0028] (4) In the present application, the Ti x Al y Si zThere are various structures in the B2 functional layer, which are respectively bimodal structure of nanometer equiaxed crystal / micron columnar crystal, equiaxed crystal grain size gradient structure, amorphous Si proportion composition gradient structure and Al content composition gradient structure. The multi-scale complex structure can improve the strength and toughness, oxidation resistance and high temperature stability of the coating, and can also reduce the residual stress in the coating and reduce the peeling of the coating.

[0029] (5) In the application, the bimodal structure WC with two grain sizes in the cemented carbide substrate has better strength and toughness than the cemented carbide substrate with a single grain size. A small amount of Ni element is added in the substrate, which can improve the corrosion resistance and high temperature oxidation resistance of the substrate without affecting the mechanical properties of the substrate.

[0030] (6) The Ti x Al y Si z B2 functional layer prepared by using high-power pulse magnetron sputtering process has a very smooth surface, which can generate less heat during machining of superalloy, thereby improving the tool life.

[0031] The technical solutions of the application are further described in combination with specific embodiments.

[0032] Embodiment 1 A high-temperature wear-resistant coated tool is prepared, and the cemented carbide milling blade of the tool model RPHT 1204M8E-MM3 is selected. The cemented carbide substrate is WC-8Co-1.5Ni (indicating that the alloy contains 8% Co, 1.5% Ni and the rest is WC, the same below), wherein the average grain size of coarse WC is 1.0 μm, and the volume fraction is 75%; the average grain size of fine WC is 0.4 μm, and the volume fraction is 25%. The hardness value of the substrate is 1400HV, and the fracture toughness is 22MPa·m 1 / 2 . The substrate surface has a micro-texture with a depth of 5 μm, a diameter of 50 μm and a spacing of 100 μm. The coating is prepared by high-power pulse magnetron sputtering process, including the following steps: S0, pretreatment; The cemented carbide tool is used as the substrate, and after sandblasting, cleaning and drying, the substrate is placed on the turret, and the substrate surface is cleaned by glow discharge.

[0033] S1, depositing W a Al b Si c B2 adhesive layer, the process parameters are: The temperature was 650°C, the bias voltage was -120 V, the sputtering power of the WB2 target was 4 kW, the sputtering power of the Al target was 1 kW, the sputtering power of the Si target was 1 kW, and the gas pressure was 0.5 Pa, where the gas was pure Ar. S2, in W a Al b Si c Ti is deposited on the surface of B2 bonding layer x Al y Si z Ti in the B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, process parameters are: The temperature is 650℃, the sputtering power of TiB2 target is 5kW, the sputtering power of Al target is 1.5~2kW, the sputtering power of Si target is 0.5~1kW, the gas pressure is 0.5Pa, and the gas is pure Ar; Ti x1 Al y1 Si z1 During the deposition of the B2 columnar crystal layer, the bias voltage increased linearly from -60 V to -80 V; the sputtering power of the Al target decreased linearly from 2 kW to 1.5 kW; the sputtering power of the Si target increased linearly from 0.5 kW to 1 kW. S3, in Ti x1 Al y1 Si z1 Ti is deposited on the surface of B2 columnar crystal layer x Al y Si z Ti in the B2 functional layer x2 Al y2 Si z2 B2 equiaxed crystal layer, process parameters are: The temperature is 650℃, the bias voltage is -80V, the sputtering power of TiB2 target is 5kW, the sputtering power of Al target is 0.7~1.5kW, the sputtering power of Si target is 2~3kW, the gas pressure is 0.5Pa, and the gas is pure Ar. x2 Al y2 Si z2 During the deposition of the B2 equiaxed crystal layer, the sputtering power of the Al target decreased linearly from 1.5kW to 0.7kW; the sputtering power of the Si target increased linearly from 2kW to 3kW. S4, steps S2 and S3 are alternately deposited, and the cycle is repeated 2 times; S5. After the temperature drops to room temperature, take out the sample to obtain a high-temperature wear-resistant coating tool.

[0034] The high temperature wear-resistant coating obtained by the preparation method has a bottom layer of 0.2 μm thick W0.65 Al 0.2 Si 0.15 B2 layer, Ti x Al y Si z B2 functional layer thickness of 4.4 μm, including columnar crystal layer Ti 0.8 Al 0.1 Si 0.1 B2 and equiaxed crystal layer Ti 0.7 Al 0.1 Si 0.2 B2, each single layer thickness of 1.1 μm.

[0035] Example 2 Preparation of a high-temperature wear-resistant coated tool, the tool model is selected as RPHT 1204M8E-MM3 cemented carbide milling insert. The cemented carbide substrate is WC-9Co-1Ni, wherein the average grain size of coarse-grained WC is 1.2 μm, and the volume fraction is 75%; the average grain size of fine-grained WC is 0.5 μm, and the volume fraction is 25%. The substrate hardness value is 1350 HV, and the fracture toughness is 22 MPa·m 1 / 2 . The substrate surface has a micro-texture with a depth of 5 μm, a diameter of 50 μm, and a spacing of 100 μm. The coating is prepared by high-power pulsed magnetron sputtering process, including the following steps: S0, pretreatment; Taking the cemented carbide tool as the substrate, after sandblasting, cleaning and drying, the substrate is placed on the turret, and the substrate surface is cleaned by glow discharge.

[0036] S1, depositing W a Al b Si c B2 adhesive layer, the process parameters are: The temperature is 650℃, the bias voltage is-120V, the sputtering power of WB2 target is 4kW, the sputtering power of Al target is 1kW, the sputtering power of Si target is 1kW, and the gas pressure is 0.5Pa, wherein the gas is pure Ar; S2, depositing Ti a Al b Si c B2 on the surface of the W x Al y Si z B2 functional layer Ti x1 Al y1 Si z1 B2 columnar crystal layer, the process parameters are: The temperature is 650℃, the sputtering power of TiB2 target is 5kW, the sputtering power of Al target is 1.5~2kW, the sputtering power of Si target is 0.5~1kW, the gas pressure is 0.5Pa, and the gas is pure Ar; Ti x1 Al y1 Si z1 During the deposition of the B2 columnar crystal layer, the bias voltage increased linearly from -60 V to -80 V; the sputtering power of the Al target decreased linearly from 2 kW to 1.5 kW; the sputtering power of the Si target increased linearly from 0.5 kW to 1 kW. S3, in Ti x1 Al y1 Si z1 Ti is deposited on the surface of B2 columnar crystal layer x Al y Si z Ti in the B2 functional layer x2 Al y2 Si z2 B2 equiaxed crystal layer, process parameters are: The temperature is 650℃, the bias voltage is -80V, the sputtering power of TiB2 target is 5kW, the sputtering power of Al target is 0.7~1.5kW, the sputtering power of Si target is 2~3kW, the gas pressure is 0.5Pa, and the gas is pure Ar. x2 Al y2 Si z2 During the deposition of the B2 equiaxed crystal layer, the sputtering power of the Al target decreased linearly from 1.5kW to 0.7kW; the sputtering power of the Si target increased linearly from 2kW to 3kW. S4, steps S2 and S3 are alternately deposited, and the cycle is repeated 2 times; S5. After the temperature drops to room temperature, take out the sample to obtain a high-temperature wear-resistant coating tool.

[0037] The high temperature wear-resistant coating obtained by the preparation method has a bottom layer of 0.2 μm thick W 0.65 Al 0.2 Si 0.15 B2 layer, Ti x Al y Si z The thickness of the B2 functional layer is 4.4 μm, which includes the columnar crystal layer Ti 0.8 Al 0.1 Si 0.1 B2 and equiaxed layer Ti 0.7 Al 0.1 Si 0.2 B2, the single layer thickness is 1.1 μm.

[0038] Example 3 A high-temperature wear-resistant coating tool was prepared. The tool model used was a RPHT 1204M8E-MM3 carbide milling insert. The carbide substrate was WC-9Co-1Ni, with coarse-grained WC having an average grain size of 1.2 μm and a volume fraction of 75%; fine-grained WC having an average grain size of 0.5 μm and a volume fraction of 25%. The substrate hardness was 1350 HV, and the fracture toughness was 21 MPa·m. 1 / 2 The substrate surface has micro-textures with a depth of 5 μm, a diameter of 50 μm, and a spacing of 100 μm. The coating is prepared using a high-power pulsed magnetron sputtering process, which includes the following steps: S0, pre-processing; The carbide tool is used as the substrate. After sandblasting, cleaning and drying, the substrate is placed on a rotating rack and the surface of the substrate is glow discharge cleaned.

[0039] S1. Depositing W on the substrate a Al b Si c B2 bonding layer, process parameters are: The temperature was 650°C, the bias voltage was -120 V, the sputtering power of the WB2 target was 4 kW, the sputtering power of the Al target was 1 kW, the sputtering power of the Si target was 1 kW, and the gas pressure was 0.5 Pa, where the gas was pure Ar. S2, in W a Al b Si c Ti is deposited on the surface of B2 bonding layer x Al y Si z Ti in the B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, process parameters are: The temperature is 650℃, the sputtering power of TiB2 target is 6kW, the sputtering power of Al target is 1.5~2kW, the sputtering power of Si target is 0.5~2kW, the gas pressure is 0.5Pa, and the gas is pure Ar; Ti x1 Al y1 Si z1 During the deposition of the B2 columnar crystal layer, the bias voltage increased linearly from -60 V to -80 V; the sputtering power of the Al target decreased linearly from 2 kW to 1.5 kW; the sputtering power of the Si target increased linearly from 0.5 kW to 2 kW. S3, in Ti x1 Al y1 Si z1 Ti is deposited on the surface of B2 columnar crystal layer x Al y Si z Ti in the B2 functional layerx2 Al y2 Si z2 B2 equiaxed crystal layer, process parameters are: temperature is 650℃, bias is -80V, sputtering power of TiB2 target is 8kW, sputtering power of Al target is 0.5~1.5kW, sputtering power of Si target is 2~3.5kW, gas pressure is 0.5Pa, wherein the gas is pure Ar. x2 Al y2 Si z2 B2 equiaxed crystal layer, process parameters are: S4, steps S2 and S3 are alternately deposited, and the cycle is 4 times; S5, after the temperature is reduced to room temperature, the sample is taken out, and a high-temperature wear-resistant coated tool is obtained.

[0040] The high-temperature wear-resistant coating prepared by the preparation method has a 0.2μm thick W 0.65 Al 0.2 Si 0.15 B2 layer, Ti x Al y Si z B2 functional layer thickness is 4.4μm, which includes columnar crystal layer Ti 0.75 Al 0.1 Si 0.15 B2 and equiaxed crystal layer Ti 0.7 Al 0.06 Si 0.24 B2, the thickness of each single layer is 0.55μm.

[0041] Comparative Example 1 The difference from Example 1 is that the cemented carbide substrate is a conventional WC-9.5Co, the WC grain size is 0.8~1.4μm, and there is no bimodal structure in the substrate.

[0042] Comparative Example 2 The difference from Example 1 is that there is no micro-texture on the surface of the substrate.

[0043] Comparative Example 3 The difference from Example 1 is that S2, only Ti a Al b Si c B2 adhesive layer surface is deposited. x1 Al y1 Si z1B2 columnar crystal layer, process parameters are: temperature is 650 DEG C, bias is -80V, TiB2 target sputtering power is 6kW, Al target sputtering power is 1.5kW, Si target sputtering power is 2kW, gas pressure is 0.5Pa, wherein the gas is pure Ar.

[0044] Comparative example 4 Different from example 1, the coating is a single layer TiB2 coating prepared by conventional high power magnetron pulse sputtering technology, and the coating thickness is 4.6μm.

[0045] Comparative example 5 Different from example 1, the coating is a single layer Al 0.67 Ti 0.33 N coating prepared by conventional high power magnetron pulse sputtering technology, and the coating thickness is 4.6μm.

[0046] The high temperature wear-resistant coated cutting tools prepared by the examples and comparative examples of the present application are subjected to performance test and milling experiment test, and the cutting experiment parameters are as follows: Material: nickel-based alloy GH4169 Cutting condition: cutting speed 75m / min, feed 0.4mm / z, cutting depth 1.2mm The wear amount VB(unit: mm) of the tool flank surface after cutting for different time is measured, and the tool flank surface wear amount is measured by OLYMPUS-SZ61 optical super depth microscope with a scale ruler.

[0047] Table 1: tool flank surface condition record after cutting for different time As can be seen from table 1, under the same cutting condition, the cutting performance of the high temperature wear-resistant coated cutting tool of the present application is better than that of the comparative examples.

[0048] The above description is only the preferred embodiments of the present application, and does not limit the patent scope of the present application, and any equivalent structural transformation or direct / indirect application in other related technical fields made by using the content of the present application is included in the patent protection scope of the present application.

Claims

1. A high temperature wear-resistant coating tool, characterized in that: include: A substrate and a high-temperature wear-resistant coating applied on the substrate; The substrate is WC-based cemented carbide; the high-temperature wear-resistant coating is prepared by physical vapor deposition method, and the high-temperature wear-resistant coating includes WC from the inside to the outside. a Al b Si c B2 bonding layer and Ti x Al y Si z B2 functional layer; where a+b+c=1, x+y+z=1; Ti x Al y Si z The B2 functional layer contains Ti x1 Al y1 Si z1 B2 columnar crystal layer and Ti x2 Al y2 Si z2 B2 equiaxed crystal layer, in which x1+y1+z1=1, x2+y2+z2=1, and the two are deposited alternately with an alternating cycle of 2 to 4 times.

2. The high temperature wear-resistant coating tool according to claim 1, characterized in that: Ti x2 Al y2 Si z2 The B2 equiaxed crystal layer is composed of amorphous Si wrapped (Ti, Al) B2 nano-equiaxed crystals; Ti x1 Al y1 Si z1 The B2 columnar crystal layer is composed of amorphous Si wrapped (Ti, Al) B2 nano-columnar crystals.

3. The high temperature wear-resistant coating tool according to claim 1, characterized in that: Ti x2 Al y2 Si z2 The B2 equiaxed crystal layer has a gradient structure along its thickness growth direction, including: (a) Grain size gradient: The average grain size decreases continuously from the substrate to the coating surface, with a variation range of 40~50nm; (b) Amorphous phase ratio gradient: The area ratio of the amorphous phase region increases continuously from the substrate to the coating surface, with a variation range of 30~50%; (c) Elemental composition gradient: The atomic percentage of Al element decreases continuously from the substrate to the coating surface, with a variation range of 1~2at%; at the same time, the atomic percentage of Si element increases continuously from the substrate to the coating surface, with a variation range of 2~3at%.

4. The high temperature wear-resistant coating tool according to claim 1, characterized in that: Ti x1 Al y1 Si z1 The B2 columnar crystal layer has a gradient structure along its thickness growth direction, including: (a) Amorphous phase ratio gradient: The area ratio of the amorphous phase region increases continuously from the substrate to the coating surface, with a variation range of 20~40%; (b) Elemental composition gradient: The atomic percentage of Al element continuously decreases from the substrate to the coating surface, with a variation range of 1.5~2.5at%; at the same time, the atomic percentage of Si element continuously increases from the substrate to the coating surface, with a variation range of 1.5~2.5at%.

5. The high temperature wear-resistant coating tool according to claim 1, characterized in that: Ti x2 Al y2 Si z2 In the B2 equiaxed crystal layer, the Si content is 6~10at%, the Al content is 2~5at%, and the atomic ratio of metal elements to B elements is 0.38≤(Ti+Al) / B≤0.42; Ti x1 Al y1 Si z1 In the B2 columnar crystal layer, the Si content is 2~5.5at%, the Al content is 3~6at%, and the atomic ratio of metal elements to B elements is 0.42≤(Ti+Al) / B≤0.

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6. The high temperature wear-resistant coating tool according to claim 1, characterized in that: W a Al b Si c The thickness of the B2 bonding layer is 0.1~0.2μm; Ti x Al y Si z The thickness of the B2 functional layer is 3.0~6.0μm, and the Ti x2 Al y2 Si z2 The thickness of the B2 equiaxed crystal layer is 0.5~1.2μm, and the Ti x1 Al y1 Si z1 The thickness of a single layer of the B2 columnar crystal layer is 0.5~1.2μm; the total thickness of the high-temperature wear-resistant coating is 3.1~6.2μm.

7. The high temperature wear-resistant coating tool according to claim 1, characterized in that: W a Al b Si c The B2 bonding layer is composed of amorphous Si wrapped with (W,Al)B2 nano-columnar crystals.

8. The high temperature wear-resistant coating tool according to claim 1, characterized in that: The matrix contains 7.0-10.0 wt% Co, 1.0-2.0 wt% Ni, and the balance is WC phase. The WC phase includes coarse-grained WC with a grain size of 0.8-1.4 μm and fine-grained WC with a grain size of 0.3-0.6 μm. The fine-grained WC exists in the gaps between the coarse-grained WC. The volume fraction of coarse-grained WC is 70-80%, and the volume fraction of fine-grained WC is 20-30%. The hardness of the matrix is ​​1300-1500 HV, and the fracture toughness is ≥18 MPa·m 1 / 2 .

9. The high temperature wear-resistant coating tool according to claim 1, characterized in that: The substrate surface is provided with a micro-texture array with a depth of 3.5~7μm and a characteristic size of 30~100μm, and the spacing between adjacent micro-textures is 1.5~3 times the characteristic size; the high-temperature wear-resistant coating is deposited to fill the micro-texture to form a mechanical anchoring structure, and the deposition profile is consistent with the micro-texture morphology by ≥95%, and the anchoring depth is ≥85% of the micro-texture depth.

10. A method for preparing a high-temperature wear-resistant coating tool according to any one of claims 1 to 9, characterized in that: The coating is prepared using a high-power pulsed magnetron sputtering process, which includes the following steps: S1. Depositing W on the substrate a Al b Si c B2 bonding layer, process parameters are: The temperature is 600~800℃, the bias voltage is -70~-120V, the sputtering power of the WB2 target is 4~6kW, the sputtering power of the Al target is 1~2kW, the sputtering power of the Si target is 0.5~3kW, and the gas pressure is 0.2~1.0Pa, where the gas is pure Ar; S2, in W a Al b Si c Ti is deposited on the surface of B2 bonding layer x Al y Si z Ti in the B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, process parameters are: The temperature is 600~800℃, the sputtering power of TiB2 target is 4~6kW, the sputtering power of Al target is 0.5~2kW, the sputtering power of Si target is 0.5~2kW, the gas pressure is 0.2~1.0Pa, and the gas is pure Ar; Ti x1 Al y1 Si z1 During the deposition of the B2 columnar crystal layer, the bias voltage increased linearly from -60 V to -70~-120 V; the sputtering power of the Al target decreased linearly from 2 kW to 0.5 kW; the sputtering power of the Si target increased linearly from 0.5 kW to 2 kW. S3, in Ti x1 Al y1 Si z1 Ti is deposited on the surface of B2 columnar crystal layer x Al y Si z Ti in the B2 functional layer x2 Al y2 Si z2 B2 equiaxed crystal layer, process parameters are: The temperature is 600~800℃, the bias voltage is -70~-120V, the sputtering power of TiB2 target is 4~8kW, the sputtering power of Al target is 0.5~1.5kW, the sputtering power of Si target is 2~4kW, the gas pressure is 0.2~1.0Pa, and the gas is pure Ar; Ti x2 Al y2 Si z2 During the deposition of the B2 equiaxed crystal layer, the sputtering power of the Al target decreased linearly from 1.5kW to 0.5kW; the sputtering power of the Si target increased linearly from 2kW to 4kW. S4, steps S2 and S3 are alternately deposited, with a cycle of 2 to 4 times; S5. After the temperature drops to room temperature, take out the sample to obtain a high-temperature wear-resistant coating tool.

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