A high temperature wear resistant coated cutting tool and method of making the same

Abstract

This invention relates to the field of coated cutting tool technology, and provides a high-temperature wear-resistant coated cutting tool and its preparation method. The cutting tool includes a substrate and a high-temperature wear-resistant coating applied to the substrate; the substrate is a WC-based cemented carbide; the coating includes WC components from the inside out. a Al b Si c B2 adhesive layer and Ti x Al y Si z B2 functional layer; where Ti x Al y Si z The B2 functional layer exhibits an alternating structure of columnar and equiaxed crystal layers, with a triple gradient structure in terms of grain size, amorphous phase ratio, and Al / Si ratio along its thickness. The matrix employs a bimodal microstructure design, where coarse-grained WC forms the framework and fine-grained WC fills the gaps, synergistically enhancing both strength and toughness. Simultaneously, a microtexture array on the matrix surface creates a mechanical interlock between the coating and the matrix, significantly strengthening the film-substrate bond. This tool combines excellent wear resistance, good toughness, superior film-substrate bond 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 superalloys.

Description

Technical Field

[0001] This invention belongs to the field of coated cutting tool technology, specifically relating to a high-temperature wear-resistant coated cutting tool and its preparation method. Background Technology

[0002] The rapid development of the aerospace industry has driven the demand for high-performance materials. Among them, titanium alloys and high-temperature alloys, with their excellent specific strength, high-temperature strength, and corrosion resistance, have become key materials for extreme service environments. However, the characteristics of these materials, especially their high strength and low thermal conductivity, pose significant challenges to their machining. When machining titanium alloys or high-temperature alloys with coated tools, the high hardness of the workpiece material leads to severe tool wear. Under high-speed or heavy-load cutting conditions, extremely high frictional and thermal stresses are generated in the tool-workpiece contact area, accelerating coating wear and significantly shortening tool life. Crucially, the low thermal conductivity of titanium alloys and high-temperature alloys hinders the effective diffusion of cutting heat generated during machining, leading to a sharp increase in cutting zone temperature. High temperatures not only soften the coating material, reducing its hardness and strength and weakening cutting performance, but also easily induce workpiece material adhesion to the tool rake face (tool sticking), severely affecting the surface quality and dimensional accuracy of the machined material. Under the coupled effects of high temperature, high mechanical stress, and high cutting speed, the coating is prone to brittle spalling or microcrack propagation, further exacerbating tool failure.

[0003] Therefore, developing cutting tools with good wear resistance, good toughness, excellent film-substrate bonding strength, and good high-temperature oxidation resistance is crucial. Physical vapor deposition (PVD) technology, due to its relatively low deposition temperature and minimal impact on the mechanical properties of the tool substrate, has become one of the important methods for preparing cutting tool coatings. As one of the most widely used coatings, AlTiN is known for its good wear resistance, high-temperature stability (derived from the dense Al2O3 oxide layer formed at high temperatures), and chemical stability. However, when cutting titanium alloys, its anti-adhesion properties are insufficient, easily leading to chip accumulation on the rake face, forming a built-up edge. The unstable growth and shedding of the built-up edge can damage the machined surface and cause cutting force fluctuations, accelerating tool wear and even causing chipping. AlCrN coatings have outstanding high-temperature oxidation resistance, but under continuous high-temperature cutting environments (typically >800℃), AlCrN coatings undergo decomposition reactions, forming CrN and AlN phases with lower hardness. This phase transformation process leads to a significant decrease in the macroscopic hardness of the coating, resulting in a deterioration in wear resistance, making it difficult to meet the long-life stable cutting requirements of difficult-to-machine materials such as high-temperature alloys. TiSiN is a typical nanocomposite coating, consisting of nanocrystalline TiN particles dispersed within an amorphous Si3N4 matrix. This structure endows the coating with ultra-high hardness (typically >40 GPa) and excellent high-temperature stability (the Si3N4 matrix effectively inhibits grain coarsening and oxidation). However, the presence of the amorphous phase reduces the coating's toughness, making it susceptible to chipping under intermittent cutting or mechanical impact conditions, and prone to micro or macroscopic damage. TiB2 coatings have an extremely low coefficient of friction and a smooth surface, effectively reducing frictional heat and cutting forces during the cutting process. Its main drawback is poor oxidation resistance; in high-temperature oxygen-containing environments, it is easily oxidized to form B2O3 and TiO2, leading to coating performance degradation. Furthermore, TiB2 coatings inherently lack toughness, also facing the risk of chipping under heavy loads or intermittent cutting. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention aims to propose a high-temperature wear-resistant coated cutting tool and its preparation method.

[0005] According to a first aspect of the present invention, the present invention provides the following technical solution:

[0006] A high-temperature wear-resistant coated cutting tool, comprising:

[0007] The substrate and the high-temperature wear-resistant coating applied to the substrate;

[0008] The substrate 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 components from the inside out. a Al b Si c B2 adhesive layer and Ti x Aly Si z B2 functional layer; where a+b+c=1, x+y+z=1.

[0009] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: Ti x Al y Si z The B2 functional layer includes Ti x1 Al y1 Si z1 B2 columnar crystal layers and Ti x2 Al y2 Si z2 B2 equiaxed crystal layers, where x1+y1+z1=1 and x2+y2+z2=1, are deposited alternately, with an alternation period of 2 to 4 times.

[0010] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: Ti x2 Al y2 Si z2 The B2 equiaxed crystal layer consists of amorphous Si-encapsulated (Ti,Al)B2 nano-equiaxed crystals; Ti x1 Al y1 Si z1 The B2 columnar crystal layer is composed of amorphous Si-encapsulated (Ti,Al)B2 nanocolumnar crystals.

[0011] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: Ti x2 Al y2 Si z2 The B2 equiaxed crystal layer exhibits a gradient structure along its thickness growth direction, including:

[0012] (a) Grain size gradient: The average grain size decreases continuously from the substrate to the coating surface, with a variation range of 40~50nm;

[0013] (b) Gradient of amorphous phase proportion: The area proportion of amorphous phase region increases continuously from the substrate to the coating surface, with a variation range of 30% to 50%;

[0014] (c) Elemental composition gradient: The atomic percentage of Al decreases continuously from the matrix to the coating surface, with a variation range of 1~2 at; while the atomic percentage of Si increases continuously from the matrix to the coating surface, with a variation range of 2~3 at.

[0015] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: Ti x1 Al y1 Si z1The columnar B2 crystal layers exhibit a gradient structure along their thickness growth direction, including:

[0016] (a) Gradient of amorphous phase proportion: The area proportion of amorphous phase region increases continuously from the substrate to the coating surface, with a variation range of 20% to 40%;

[0017] (b) Elemental composition gradient: The atomic percentage of Al decreases continuously from the substrate to the coating surface, with a variation range of 1.5~2.5at; while the atomic percentage of Si increases continuously from the substrate to the coating surface, with a variation range of 1.5~2.5at.

[0018] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: 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 the metal element to the B element is 0.38≤(Ti+Al) / B≤0.42.

[0019] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: Ti x1 Al y1 Si z1 In the columnar B2 crystal layer, the Si content is 2~5.5 at%, the Al content is 3~6 at%, and the atomic ratio of the metal element to the B element is 0.42≤(Ti+Al) / B≤0.48.

[0020] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: W a Al b Si c The thickness of the B2 adhesive layer is 0.1~0.2μm; Ti x Al y Si z The thickness of the B2 functional layer is 3.0~6.0 μm, and the Ti layer... x2 Al y2 Si z2 The thickness of a single equiaxed B2 crystal layer is 0.5~1.2μm, and the thickness of a Ti layer is... x1 Al y1 Si z1 The thickness of a single columnar crystal layer of B2 is 0.5~1.2μm; the total thickness of the high-temperature wear-resistant coating is 3.1~6.2μm.

[0021] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, wherein: W a Al b Si cThe B2 bonding layer consists of amorphous Si-encapsulated (W,Al)B2 nanocolumnar crystals.

[0022] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, the matrix comprises 7.0~10.0wt% Co, 1.0~2.0wt% Ni, and the balance being WC phase; wherein the WC phase comprises coarse-grained WC with a grain size of 0.8~1.4μm and fine-grained WC with a grain size of 0.3~0.6μm, and the fine-grained WC exists in the interstices of 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%.

[0023] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, the substrate surface is provided with a microtexture array with a depth of 3.5~7μm and a feature size of 30~100μm, and the spacing between adjacent microtextures is 1.5~3 times the feature size; the high-temperature wear-resistant coating is deposited to fill the microtexture to form a mechanical anchoring structure, and the deposition profile matches the microtexture morphology ≥95%, and the anchoring depth is ≥85% of the microtexture depth.

[0024] As a preferred embodiment of the high-temperature wear-resistant coated cutting tool of the present invention, the hardness of the substrate is 1300~1500HV, and the fracture toughness is ≥18MPa·m. 1 / 2 .

[0025] According to a second aspect of the present invention, the present invention provides the following technical solution:

[0026] A method for preparing the above-mentioned high-temperature wear-resistant coated cutting tool, wherein the coating is prepared by high-power pulsed magnetron sputtering process, including the following steps:

[0027] S1, Depositing W on the substrate a Al b Si c B2 adhesive layer, process parameters are:

[0028] The temperature is 600~800℃, the bias voltage is -70~-120V, the sputtering power of WB2 target is 4~6kW, the sputtering power of Al target is 1~2kW, the sputtering power of Si target is 0.5~3kW, and the gas pressure is 0.2~1.0Pa, wherein the gas is pure Ar;

[0029] S2, in W a Al b Si c Ti deposited on the surface of B2 adhesive layer x Al y Si z Ti in the B2 functional layer x1 Al y1 Si z1B2 columnar crystal layer, process parameters are:

[0030] The sputtering temperature is 600~800℃, the sputtering power of the TiB2 target is 4~6kW, the sputtering power of the Al target is 0.5~2kW, the sputtering power of the Si target is 0.5~2kW, and the gas pressure is 0.2~1.0Pa, wherein the gas is pure Ar; Ti x1 Al y1 Si z1 During the deposition of B2 columnar crystal layers, the bias voltage increases linearly from -60V to -70~-120V; the sputtering power of the Al target decreases linearly from 2kW to 0.5kW; and the sputtering power of the Si target increases linearly from 0.5kW to 2kW.

[0031] S3, in Ti x1 Al y1 Si z1 Ti deposition 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:

[0032] The sputtering power was 4-8 kW for TiB2 targets, 0.5-1.5 kW for Al targets, and 2-4 kW for Si targets, with a gas pressure of 0.2-1.0 Pa, where the gas was pure Ar; Ti x2 Al y2 Si z2 During the deposition of B2 equiaxed crystal layers, 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.

[0033] S4, steps S2 and S3 are deposited alternately, with a cycle of 2 to 4 times;

[0034] S5. After the temperature drops to room temperature, the sample is removed to obtain a high-temperature wear-resistant coated cutting tool.

[0035] In a preferred embodiment of the method for preparing a high-temperature wear-resistant coated cutting tool according to the present invention, the method further includes the following steps before step S1:

[0036] S0. Pretreatment: Using carbide cutting tools as the substrate, the substrate is sandblasted, cleaned and dried, and then placed on a rotating frame for glow discharge cleaning of the substrate surface.

[0037] The beneficial effects of this invention are as follows:

[0038] This invention provides a high-temperature wear-resistant coated cutting tool and its preparation method. The cutting tool includes a substrate and a high-temperature wear-resistant coating applied to the substrate; the substrate is a WC-based cemented carbide; the coating includes WC components from the inside out. a Al b Si c B2 adhesive layer and Ti x Al y Si z B2 functional layer; where Ti x Al y Si z The B2 functional layer exhibits an alternating structure of columnar and equiaxed crystal layers, with a triple gradient structure in terms of grain size, amorphous phase ratio, and Al / Si ratio along its thickness. The matrix employs a bimodal microstructure design, where coarse-grained WC forms the framework and fine-grained WC fills the gaps, synergistically enhancing both strength and toughness. Simultaneously, a microtexture array on the matrix surface creates a mechanical interlock between the coating and the matrix, significantly strengthening the film-substrate bond. This tool combines excellent wear resistance, good toughness, superior film-substrate bond 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 superalloys. Attached Figure Description

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0040] Figure 1 This is a cross-sectional schematic diagram of the high-temperature wear-resistant coated cutting tool of the present invention.

[0041] In the diagram, 100 represents the matrix; 200 represents W. a Al b Si c B2 adhesive layer; 300-Ti x Al y Si z B2 functional layer; 310-Ti x1 Al y1 Si z1 B2 columnar crystal layers; 320-Ti x2 Al y2 Si z2 B2 isometric crystal layer.

[0042] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0043] The technical solutions described below in conjunction with the embodiments will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] This invention proposes a high-temperature wear-resistant coated cutting tool and its preparation method. The cutting tool includes:

[0045] Substrate 100 and high-temperature wear-resistant coating applied to substrate 100;

[0046] 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 W from the inside out. a Al b Si c B2 adhesive layer 200 and Ti x Al y Si z B2 functional layer 300. Ti x Al y Si z B2 functional layer 300 includes Ti x1 Al y1 Si z1 B2 columnar crystal layers 310 and Ti x2 Al y2 Si z2 B2 equiaxed crystal layers 320 are deposited alternately, with an alternation cycle of 2-4 times. The high-temperature wear-resistant coated cutting tools of this invention exhibit good wear resistance, good toughness, excellent film-substrate bonding strength, and good resistance to high-temperature oxidation. Specific characteristics are as follows:

[0047] (1) In this invention, microtexturing treatment of the substrate surface can effectively improve the film-substrate adhesion and also increase the cutting tool life during the cutting process. The high-temperature wear-resistant coating contains W... a Al b Si c B2 adhesive layer, located between the substrate and Ti x Al y Si z The B2 functional layers exhibit excellent adhesion to both the functional layers and the matrix, significantly enhancing the bond strength between them. During high-temperature machining, the W element in the matrix reacts with the W... a Al b Si c In the B2 adhesive layer, W element has a strong affinity and readily undergoes interdiffusion, thus improving the film-substrate bonding force; while Wa Al b Si c In the B2 adhesive layer, Al, Si, and B elements can react with Ti. x Al y Si z In the B2 functional layer, Al, Si, and B elements have strong affinity and readily interdiffusion, thereby improving the adhesion between coating layers. a Al b Si c B2 adhesive layer can also be used as Ti x Al y Si z The epitaxial growth template of the B2 functional layer enables Ti x Al y Si z The B2 functional layer was grown into the desired structure. Furthermore, due to the compositional gradient structural design, in Ti... x Al y Si z In the B2 functional layer, there is a transition zone between columnar crystals and equiaxed crystals, so there is no obvious coating layering interface between them, resulting in better coating adhesion compared to other multilayer coatings.

[0048] (2) In this invention, Si is incorporated into the coating in an amorphous state, and the proportion of the amorphous phase increases with the increase of Si content. By controlling the Si incorporation, the Si content in the Ti coating is optimized. x Al y Si z The presence of amorphous phases throughout the B2 functional layer reduces defects within the coating and hinders gas ingress, further enhancing its mechanical properties, oxidation resistance, and high-temperature stability. Furthermore, controlling the Si content can alter the crystal structure and morphology within the coating, resulting in a complex multi-scale structure. Al incorporation can form an (Al,Ti)B2 solid solution with TiB2, improving the coating's hardness, toughness, and high-temperature oxidation resistance.

[0049] (3) In this invention, for Ti x Al y Si z The columnar crystal layer in the B2 functional layer can be made to have a more uniform overall structure by using gradient bias, which improves the coating performance. The gradient structure of Al element content introduced into the columnar crystal layer can enhance the coating hardness while ensuring that its toughness remains basically unchanged.

[0050] (4) In this invention, Ti x Al y Si zThe B2 functional layer contains multiple structures, namely a bimodal structure of nano-equiaxed crystals / micron columnar crystals, a gradient structure of equiaxed crystal grain size, a compositional gradient structure of amorphous Si content, and a compositional gradient structure of Al content. This multi-scale complex structure can improve the coating's toughness, oxidation resistance, and high-temperature stability on the one hand, and reduce the residual stress inside the coating on the other hand, thus reducing coating peeling.

[0051] (5) In this invention, the cemented carbide matrix has a bimodal microstructure WC with two different grain sizes, which has better strength and toughness than a cemented carbide matrix with a single grain size. Adding a small amount of Ni to the matrix can improve the corrosion resistance and high-temperature oxidation resistance of the matrix without affecting its mechanical properties.

[0052] (6) Ti prepared using high-power pulsed magnetron sputtering process x Al y Si z The B2 functional layer has a very smooth surface, which allows it to generate less heat during the machining of high-temperature alloys, thereby improving tool life.

[0053] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0054] Example 1

[0055] A high-temperature wear-resistant coated cutting tool was prepared, using RPHT 1204M8E-MM3 carbide end mill inserts. The carbide matrix was WC-8Co-1.5Ni (meaning the alloy contains 8% Co, 1.5Ni, and the remainder WC by mass fraction, hereinafter the same), wherein the coarse-grained WC had an average grain size of 1.0 μm and accounted for 75% by volume; and the fine-grained WC had an average grain size of 0.4 μm and accounted for 25% by volume. The matrix hardness was 1400 HV, and the fracture toughness was 22 MPa·m. 1 / 2 The substrate surface exhibits a microtexture with a depth of 5 μm, a diameter of 50 μm, and a spacing of 100 μm. The coating was prepared using a high-power pulsed magnetron sputtering process, comprising the following steps:

[0056] S0, Pre-processing;

[0057] Using carbide cutting tools as the substrate, the substrate is sandblasted, cleaned, and dried before being placed on a rotating frame for glow discharge cleaning of the substrate surface.

[0058] S1, Depositing W on the substrate a Al b Si c B2 adhesive layer, process parameters are:

[0059] The temperature is 650℃, the bias voltage is -120V, the sputtering power of the WB2 target is 4kW, the sputtering power of the Al target is 1kW, the sputtering power of the Si target is 1kW, and the gas pressure is 0.5Pa, wherein the gas is pure Ar.

[0060] S2, in W a Al b Si c Ti deposited on the surface of B2 adhesive layer x Al y Si z Ti in the B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, process parameters are:

[0061] The temperature was 650℃, the sputtering power of the TiB2 target was 5kW, the sputtering power of the Al target was 1.5~2kW, the sputtering power of the Si target was 0.5~1kW, and the gas pressure was 0.5Pa, wherein the gas was pure Ar; Ti x1 Al y1 Si z1 During the deposition of B2 columnar crystal layers, the bias voltage increases linearly from -60V to -80V; the sputtering power of the Al target decreases linearly from 2kW to 1.5kW; and the sputtering power of the Si target increases linearly from 0.5kW to 1kW.

[0062] S3, in Ti x1 Al y1 Si z1 Ti deposition 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:

[0063] The temperature was 650℃, the bias voltage was -80V, the sputtering power of the TiB2 target was 5kW, the sputtering power of the Al target was 0.7~1.5kW, the sputtering power of the Si target was 2~3kW, and the gas pressure was 0.5Pa, wherein the gas was pure Ar. x2 Al y2 Si z2 During the deposition of B2 equiaxed crystal layers, 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.

[0064] Steps S4, S2, and S3 are deposited alternately, with a cycle of 2 times;

[0065] S5. After the temperature drops to room temperature, the sample is removed to obtain a high-temperature wear-resistant coated cutting tool.

[0066] The high-temperature wear-resistant coating obtained by this preparation method has a base layer of 0.2 μm thick W. 0.65 Al 0.2 Si 0.15 B2 layer, Ti x Al y Si z The B2 functional layer has a thickness of 4.4 μm, which includes columnar Ti crystal layers. 0.8 Al 0.1 Si 0.1 B2 and equiaxed Ti 0.7 Al 0.1 Si 0.2 B2, with a single layer thickness of 1.1 μm.

[0067] Example 2

[0068] A high-temperature wear-resistant coated cutting tool was prepared, using RPHT 1204M8E-MM3 carbide end mill inserts. The carbide matrix was WC-9Co-1Ni, with coarse-grained WC having an average grain size of 1.2 μm and a volume fraction of 75%, and fine-grained WC having an average grain size of 0.5 μm and a volume fraction of 25%. The matrix hardness was 1350 HV, and the fracture toughness was 22 MPa·m. 1 / 2 The substrate surface exhibits a microtexture with a depth of 5 μm, a diameter of 50 μm, and a spacing of 100 μm. The coating was prepared using a high-power pulsed magnetron sputtering process, comprising the following steps:

[0069] S0, Pre-processing;

[0070] Using carbide cutting tools as the substrate, the substrate is sandblasted, cleaned, and dried before being placed on a rotating frame for glow discharge cleaning of the substrate surface.

[0071] S1, Depositing W on the substrate a Al b Si c B2 adhesive layer, process parameters are:

[0072] The temperature is 650℃, the bias voltage is -120V, the sputtering power of the WB2 target is 4kW, the sputtering power of the Al target is 1kW, the sputtering power of the Si target is 1kW, and the gas pressure is 0.5Pa, wherein the gas is pure Ar.

[0073] S2, in W a Al b Si c Ti deposited on the surface of B2 adhesive layer x Al y Si zTi in the B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, process parameters are:

[0074] The temperature was 650℃, the sputtering power of the TiB2 target was 5kW, the sputtering power of the Al target was 1.5~2kW, the sputtering power of the Si target was 0.5~1kW, and the gas pressure was 0.5Pa, wherein the gas was pure Ar; Ti x1 Al y1 Si z1 During the deposition of B2 columnar crystal layers, the bias voltage increases linearly from -60V to -80V; the sputtering power of the Al target decreases linearly from 2kW to 1.5kW; and the sputtering power of the Si target increases linearly from 0.5kW to 1kW.

[0075] S3, in Ti x1 Al y1 Si z1 Ti deposition 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:

[0076] The temperature was 650℃, the bias voltage was -80V, the sputtering power of the TiB2 target was 5kW, the sputtering power of the Al target was 0.7~1.5kW, the sputtering power of the Si target was 2~3kW, and the gas pressure was 0.5Pa, wherein the gas was pure Ar. x2 Al y2 Si z2 During the deposition of B2 equiaxed crystal layers, 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.

[0077] Steps S4, S2, and S3 are deposited alternately, with a cycle of 2 times;

[0078] S5. After the temperature drops to room temperature, the sample is removed to obtain a high-temperature wear-resistant coated cutting tool.

[0079] The high-temperature wear-resistant coating obtained by this preparation method has a base layer of 0.2 μm thick W. 0.65 Al 0.2 Si 0.15 B2 layer, Ti x Al y Si z The B2 functional layer has a thickness of 4.4 μm, which includes columnar Ti crystal layers. 0.8 Al0.1 Si 0.1 B2 and equiaxed Ti 0.7 Al 0.1 Si 0.2 B2, with a single layer thickness of 1.1 μm.

[0080] Example 3

[0081] A high-temperature wear-resistant coated cutting tool was prepared, using RPHT 1204M8E-MM3 carbide end mill inserts. The carbide matrix was WC-9Co-1Ni, with coarse-grained WC having an average grain size of 1.2 μm and a volume fraction of 75%, and fine-grained WC having an average grain size of 0.5 μm and a volume fraction of 25%. The matrix hardness was 1350 HV, and the fracture toughness was 21 MPa·m. 1 / 2 The substrate surface exhibits a microtexture with a depth of 5 μm, a diameter of 50 μm, and a spacing of 100 μm. The coating was prepared using a high-power pulsed magnetron sputtering process, comprising the following steps:

[0082] S0, Pre-processing;

[0083] Using carbide cutting tools as the substrate, the substrate is sandblasted, cleaned, and dried before being placed on a rotating frame for glow discharge cleaning of the substrate surface.

[0084] S1, Depositing W on the substrate a Al b Si c B2 adhesive layer, process parameters are:

[0085] The temperature is 650℃, the bias voltage is -120V, the sputtering power of the WB2 target is 4kW, the sputtering power of the Al target is 1kW, the sputtering power of the Si target is 1kW, and the gas pressure is 0.5Pa, wherein the gas is pure Ar.

[0086] S2, in W a Al b Si c Ti deposited on the surface of B2 adhesive layer x Al y Si z Ti in the B2 functional layer x1 Al y1 Si z1 B2 columnar crystal layer, process parameters are:

[0087] The temperature was 650℃, the sputtering power of the TiB2 target was 6kW, the sputtering power of the Al target was 1.5~2kW, the sputtering power of the Si target was 0.5~2kW, and the gas pressure was 0.5Pa, wherein the gas was pure Ar; Ti x1 Al y1 Si z1During the deposition of B2 columnar crystal layers, the bias voltage increases linearly from -60V to -80V; the sputtering power of the Al target decreases linearly from 2kW to 1.5kW; and the sputtering power of the Si target increases linearly from 0.5kW to 2kW.

[0088] S3, in Ti x1 Al y1 Si z1 Ti deposition 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:

[0089] The temperature was 650℃, the bias voltage was -80V, the sputtering power of the TiB2 target was 8kW, the sputtering power of the Al target was 0.5~1.5kW, the sputtering power of the Si target was 2~3.5kW, and the gas pressure was 0.5Pa, wherein the gas was pure Ar. x2 Al y2 Si z2 During the deposition of B2 equiaxed crystal layers, 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 3.5kW.

[0090] S4, steps S2 and S3 are deposited alternately, with a cycle of 4 times;

[0091] S5. After the temperature drops to room temperature, the sample is removed to obtain a high-temperature wear-resistant coated cutting tool.

[0092] The high-temperature wear-resistant coating obtained by this preparation method has a base layer of 0.2 μm thick W. 0.65 Al 0.2 Si 0.15 B2 layer, Ti x Al y Si z The B2 functional layer has a thickness of 4.4 μm, which includes a columnar Ti layer. 0.75 Al 0.1 Si 0.15 B2 and equiaxed Ti 0.7 Al 0.06 Si 0.24 B2, with a single layer thickness of 0.55μm.

[0093] Comparative Example 1

[0094] The difference from Example 1 is that the cemented carbide matrix is ​​conventional WC-9.5Co, the WC grain size is 0.8~1.4μm, and there is no bimodal microstructure inside the matrix.

[0095] Comparative Example 2

[0096] The difference from Example 1 is that there is no microtexture on the substrate surface.

[0097] Comparative Example 3

[0098] The difference from Example 1 is that, in S2, in W a Al b Si c Only Ti is deposited on the surface of the B2 adhesive layer. x1 Al y1 Si z1 The process parameters for the B2 columnar crystal layer are as follows: temperature 650℃, bias voltage -80V, sputtering power of TiB2 target 6kW, sputtering power of Al target 1.5kW, sputtering power of Si target 2kW, and gas pressure 0.5Pa, wherein the gas is pure Ar.

[0099] Comparative Example 4

[0100] The difference from Example 1 is that the coating is a single-layer TiB2 coating prepared by conventional high-power magnetron pulse sputtering technology, with a coating thickness of 4.6 μm.

[0101] Comparative Example 5

[0102] The difference from Example 1 is that the coating is a single layer of Al prepared by conventional high-power magnetron pulse sputtering technology. 0.67 Ti 0.33 The coating is N-coated with a thickness of 4.6 μm.

[0103] The following tests the performance and milling experiments of the high-temperature wear-resistant coated cutting tools prepared according to the embodiments and comparative examples of the present invention. The cutting experiment parameters are as follows:

[0104] Material: Nickel-based alloy GH4169

[0105] Cutting conditions: Cutting speed 75 m / min, feed rate 0.4 mm / z, depth of cut 1.2 mm

[0106] The wear amount VB (in mm) of the tool flank face after different cutting times is shown in Table 1. The wear amount of the tool flank face was measured using an OLYMPUS-SZ61 optical ultra-depth-of-field microscope with a graduated scale.

[0107] Table 1. Record of tool flank face condition after different cutting times.

[0108]

[0109] As can be seen from Table 1, under the same cutting conditions, the cutting performance of the high-temperature wear-resistant coated tool of the present invention is better than that of the comparative example.

[0110] The above description is merely a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention under the inventive concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A high-temperature wear-resistant coated cutting tool, characterized in that, include: The substrate and the high-temperature wear-resistant coating applied to the substrate; The substrate 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 components from the inside out. a Al b Si c B2 adhesive 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 includes Ti x1 Al y1 Si z1 B2 columnar crystal layers and Ti x2 Al y2 Si z2 B2 equiaxed crystal layers, where x1+y1+z1=1 and x2+y2+z2=1, are deposited alternately, with an alternation period of 2 to 4 times.

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

3. The high-temperature wear-resistant coated cutting tool according to claim 1, characterized in that, Ti x2 Al y2 Si z2 The B2 equiaxed crystal layer exhibits 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) Gradient of amorphous phase proportion: The area proportion of amorphous phase region increases continuously from the substrate to the coating surface, with a variation range of 30% to 50%; (c) Elemental composition gradient: The atomic percentage of Al decreases continuously from the matrix to the coating surface, with a variation range of 1~2 at; while the atomic percentage of Si increases continuously from the matrix to the coating surface, with a variation range of 2~3 at.

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

5. The high-temperature wear-resistant coated cutting 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 the metal element to the B element is 0.38≤(Ti+Al) / B≤0.42; Ti x1 Al y1 Si z1 In the columnar B2 crystal layer, the Si content is 2~5.5 at%, the Al content is 3~6 at%, and the atomic ratio of the metal element to the B element is 0.42≤(Ti+Al) / B≤0.

48.

6. The high-temperature wear-resistant coated cutting tool according to claim 1, characterized in that, W a Al b Si c The thickness of the B2 adhesive layer is 0.1~0.2μm; Ti x Al y Si z The thickness of the B2 functional layer is 3.0~6.0 μm, and the Ti layer... x2 Al y2 Si z2 The thickness of a single equiaxed B2 crystal layer is 0.5~1.2μm, and the thickness of a Ti layer is... x1 Al y1 Si z1 The thickness of a single columnar crystal layer of B2 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 coated cutting tool according to claim 1, characterized in that, W a Al b Si c The B2 bonding layer consists of amorphous Si-encapsulated (W,Al)B2 nanocolumnar crystals.

8. The high-temperature wear-resistant coated cutting tool according to claim 1, characterized in that, The matrix comprises 7.0–10.0 wt% Co, 1.0–2.0 wt% Ni, and the balance being WC phase; the WC phase consists of 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, with the fine-grained WC existing in the interstices of 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 matrix has a hardness of 1300–1500 HV and a fracture toughness ≥18 MPa·m. 1 / 2 .

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

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

Images