High-temperature self-lubricating wear-resistant coated cutting tool and method for manufacturing same

Abstract

The present application relates to the technical field of coated tools, and provides a high-temperature self-lubricating wear-resistant coated tool and a preparation method thereof. The high-temperature self-lubricating wear-resistant coated tool prepared by using a high-power pulse magnetron sputtering process comprises a substrate and a high-temperature self-lubricating wear-resistant coating deposited on the substrate, which comprises, from the surface of the substrate outward, a Ta adhesive layer, a TaN transition layer, a TaB x N y coating layer, wherein 0≤x≤2, 0≤y≤1; Ta z Cr t B2 coating layer, wherein 0≤z≤1, 0≤t≤1, and 0.9≤z+t≤1.1; Cr a Ta b V c B2 coating layer, wherein 0

Description

Technical Field

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

[0002] High-temperature alloys are special metallic materials mainly based on iron, nickel, and cobalt, formed by adding various alloying elements. They maintain high strength and resistance to oxidation and corrosion, especially under high-temperature environments, and are therefore widely used in the aerospace field. However, machining high-temperature alloys with carbide-coated tools presents several challenges: 1) Insufficient heat resistance of the coated tools: The cutting zone temperature of high-temperature alloys often exceeds 1000℃, leading to plastic deformation of the tool due to the softening of the cobalt binder phase. 2) Poor anti-adhesion properties causing built-up edge: Nickel in high-temperature alloys readily undergoes chemical affinity with carbide, forming a tool-chip bond layer (such as Ni-WC compounds), resulting in increased cutting force fluctuations and periodic chipping of the built-up edge, causing micro-chipping of the tool. 3) Insufficient wear resistance accelerating flank wear: Hard phases (such as MC carbides) in high-temperature alloys cause abrasive wear, exacerbating tool failure. 4) Insufficient toughness leading to chipping failure: Carbide tools have low bending strength, making them prone to brittle chipping in interrupted cutting of high-temperature alloys (such as blade tenoning). Therefore, the requirements for cutting tools for high-temperature alloys are excellent heat resistance and thermal stability, good hardness, and sufficient toughness. To address the problems arising in the machining of high-temperature alloys, it is essential to improve the heat resistance, thermal stability, anti-adhesion properties, wear resistance, and coating adhesion strength of the coating as quickly as possible.

[0003] Botryoid compounds are widely used in machining high-temperature alloys. For example, PVD-prepared TiB2 coatings are prone to chipping during machining of high-temperature alloys due to their high hardness, thus affecting cutting performance. Some literature reports that adding appropriate Cr elements to TiB2 coatings can improve their coating hardness and crack resistance, but their high-temperature stability is poor. Some studies have shown that TaN has excellent high-temperature thermal stability and can maintain good performance at high temperatures, but its hardness is low. The doping of V elements into AlTiN can lower the coefficient of friction of the coating, reduce the generation of built-up edge, and extend the tool life, but its hardness is also low. Summary of the Invention

[0004] To address the problems existing in the prior art, this invention aims to propose a high-temperature self-lubricating wear-resistant coated cutting tool and its preparation method, which has excellent thermal stability and bonding strength, as well as outstanding anti-sticking properties and high wear resistance.

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

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

[0007] A substrate and a high-temperature self-lubricating and wear-resistant coating deposited on the substrate;

[0008] The high-temperature self-lubricating and wear-resistant coating is prepared by physical vapor deposition method, and sequentially includes from the substrate surface outwards:

[0009] Ta bonding layer;

[0010] TaN transition layer;

[0011] The first sub-coating, and the first sub-coating is TaB x N y coating, where 0 ≤ x ≤ 2 and 0 ≤ y ≤ 1;

[0012] The second sub-coating, and the second sub-coating is Ta z Cr t B2 coating, where 0 ≤ z ≤ 1, 0 ≤ t ≤ 1, and 0.9 ≤ z + t ≤ 1.1;

[0013] The third sub-coating, and the third sub-coating is Cr a Ta b V c B2 coating, where 0 < a ≤ 1, 0 < b ≤ 0.4, 0 ≤ c ≤ 0.1, and 0.9 ≤ a + b + c ≤ 1.1; and

[0014] CrB2 coating.

[0015] As a preferred scheme of a high-temperature self-lubricating and wear-resistant coating tool according to the present invention, wherein: in the thickness direction of the first sub-coating (consistent with the direction from the substrate surface outwards), the x value increases correspondingly with the increase of the coating thickness, and at the same time the y value decreases correspondingly with the increase of the coating thickness, so as to form a compositional gradient with increasing B content and decreasing N content in the first sub-coating, and the compositional gradient tends to be constant after the coating thickness reaches a specific value.

[0016] As a preferred scheme of a high-temperature self-lubricating and wear-resistant coating tool according to the present invention, wherein: the first sub-coating includes TaN nanocrystals and TaB2 nanocrystals, and at least part of the surfaces of the TaN nanocrystals and TaB2 nanocrystals are coated with an amorphous BN layer.

[0017] As a preferred scheme of a high-temperature self-lubricating and wear-resistant coating tool according to the present invention, wherein: in the thickness direction of the second sub-coating (consistent with the direction from the substrate surface outwards), the t value increases correspondingly with the increase of the coating thickness, and at the same time the z value decreases correspondingly with the increase of the coating thickness, so as to form a compositional gradient with increasing Cr content and decreasing Ta content in the second sub-coating, and the compositional gradient tends to be constant after the coating thickness reaches a specific value.

[0018] As a preferred embodiment of the high-temperature self-lubricating wear-resistant coated cutting tool of the present invention, in the thickness direction of the third sub-coating (consistent with the direction from the substrate surface outward), the value of a increases accordingly with the increase of the coating thickness, the value of b decreases accordingly with the increase of the coating thickness, and the value of c gradually increases with the increase of the coating thickness, thereby forming a composition gradient in the third sub-coating with increasing Cr content, decreasing Ta content, and increasing V content, and the composition gradient tends to be constant after the coating thickness reaches a certain value.

[0019] As a preferred embodiment of the high-temperature self-lubricating wear-resistant coated cutting tool of the present invention, the total thickness of the high-temperature self-lubricating wear-resistant coating is 1.5~6µm, wherein the thickness of the Ta bonding layer is 0.05~0.1µm, the thickness of the TaN transition layer is 0.1~0.2µm, the thickness of the first sub-coating is 0.2~1µm, the thickness of the second sub-coating is 0.2~1.5µm, the thickness of the third sub-coating is 0.2~3µm, and the thickness of the CrB2 coating is 0.5~2µm.

[0020] As a preferred embodiment of the high-temperature self-lubricating wear-resistant coated cutting tool of the present invention, the grain size of the first sub-coating is 20~200nm; the grain size of the second sub-coating is 20~100nm; the grain size of the third sub-coating is 2~50nm; and the grain size of the CrB2 coating is 2~25nm.

[0021] As a preferred embodiment of the high-temperature self-lubricating wear-resistant coated cutting tool of the present invention, the Vickers hardness of the first sub-coating is 22~30Ga; the Vickers hardness of the second sub-coating is 24~32Ga; the Vickers hardness of the third sub-coating is 26~34Ga; and the Vickers hardness of the CrB2 coating is 30~42Ga.

[0022] According to a second aspect of the present invention, the present invention provides the following technical solution:

[0023] A method for preparing a high-temperature self-lubricating wear-resistant coated cutting tool, wherein the coating is prepared by high-power pulsed magnetron sputtering process, including the following steps:

[0024] S1. Deposit a Ta binder layer on the substrate. The deposition process parameters are as follows:

[0025] Temperature: 600~750℃; Bias voltage: -150~-200V; Ta target sputtering power: 6000~8000W; Pressure: 0.4~0.8Pa.

[0026] S2. Deposit a TaN transition layer on the surface of the Ta binder layer. The deposition process parameters are as follows:

[0027] Temperature: 600~750℃, bias voltage: -100~-150V, Ta target sputtering power: 6000~8000W, N2 flow rate: 200~300sccm, pressure: 0.4~0.8Pa;

[0028] S3. Deposit the first sub-coating on the surface of the TaN transition layer. The deposition process parameters are as follows:

[0029] The temperature was 600~750℃, the bias voltage was -40~-100V, the sputtering power of the TaB2 target was 1000~4500W, the N2 flow rate was 0~300sccm, and the pressure was 0.4~0.8Pa; the N2 flow rate gradually decreased during the deposition process.

[0030] S4. Deposit a second sub-coating on the surface of the first sub-coating; the deposition process parameters are:

[0031] The temperature was 600~750℃, the bias voltage was -60~-120V, the sputtering power of TaB2 target was 1000~4500W, the sputtering power of CrB2 target was 1000~4500W, and the pressure was 0.4~0.8Pa. During the deposition process, the sputtering power of TaB2 target gradually decreased, while the sputtering power of CrB2 target gradually increased.

[0032] S5. Deposit a third sub-coating on the surface of the second sub-coating; the deposition process parameters are:

[0033] The temperature was 600~750℃, the bias voltage was -80~-120V, the sputtering power of TaB2 target was 1000~4500W, the sputtering power of CrB2 target was 1000~4500W, the sputtering power of V target was 1000~6000W, and the pressure was 0.4~0.8Pa. During the deposition process, the sputtering power of TaB2 target gradually decreased, the sputtering power of CrB2 target gradually increased, and the sputtering power of V target gradually increased.

[0034] S6. Deposit a CrB2 coating on the surface of the third sub-coating; the deposition process parameters are as follows:

[0035] Temperature: 600~750℃, bias voltage: -80~-120V, sputtering power of CrB2 target: 3000~4500W, pressure: 0.4~0.8Pa;

[0036] S7. After the temperature drops to room temperature, the sample is taken out at room temperature to obtain a high-temperature self-lubricating wear-resistant coated tool.

[0037] As a preferred embodiment of the method for preparing a high-temperature self-lubricating wear-resistant coated cutting tool according to the present invention, it further includes:

[0038] S0. Pretreatment: Using cemented carbide as the substrate for the cutting tool, the substrate is sandblasted, cleaned, and dried before being placed on a rotating frame for glow discharge cleaning of the substrate surface.

[0039] The beneficial effects of the present invention are as follows:

[0040] The present invention provides a high-temperature self-lubricating and wear-resistant coated tool and a preparation method thereof. The high-temperature self-lubricating and wear-resistant coated tool prepared by a high-power pulsed magnetron sputtering process includes a substrate and a high-temperature self-lubricating and wear-resistant coating deposited on the substrate, which sequentially includes from the substrate surface outward: a Ta bonding layer; a TaN transition layer; a first sub-layer, the first sub-layer is a TaB x N y coating, where 0 ≤ x ≤ 2, 0 ≤ y ≤ 1; a second sub-layer, the second sub-layer is a Ta z Cr t B2 coating, where 0 ≤ z ≤ 1, 0 ≤ t ≤ 1, and 0.9 ≤ z + t ≤ 1.1; a third sub-layer, the third sub-layer is a Cr a Ta b V c B2 coating, where 0 < a ≤ 1, 0 < b ≤ 0.4, 0 ≤ c ≤ 0.1, and 0.9 ≤ a + b + c ≤ 1.1; and a CrB2 coating. This high-temperature self-lubricating and wear-resistant coating not only has excellent thermal stability and bonding strength, but also has excellent anti-adhesion and high wear resistance. Through the coordinated action of multiple layers of coatings, the present invention can solve the problems of easy wear and chip adhesion when cutting superalloy materials. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on the structures shown in these drawings.

[0042] Figure 1 is a cross-sectional schematic view of the high-temperature self-lubricating and wear-resistant coated tool of the present invention.

[0043] In the figure, 1 - substrate; 2 - Ta bonding layer; 3 - TaN transition layer; 4 - first sub-layer; 5 - second sub-layer; 6 - third sub-layer; 7 - CrB2 coating.

[0044] The realization, functional characteristics, and advantages of the object of the present invention will be further described in conjunction with the embodiments and with reference to the drawings. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] The technical solutions in the embodiments will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0046] As Figure 1 shown, the present invention provides a high-temperature self-lubricating and wear-resistant coating tool, comprising:

[0047] a substrate 1 and a high-temperature self-lubricating and wear-resistant coating deposited on the substrate;

[0048] The high-temperature self-lubricating and wear-resistant coating is prepared by physical vapor deposition method, and sequentially includes from the surface of the substrate 1 to the outside:

[0049] a Ta bonding layer 2;

[0050] a TaN transition layer 3;

[0051] a first sub-coating 4, and the first sub-coating 4 is a TaB x N y coating, where 0 ≤ x ≤ 2, 0 ≤ y ≤ 1;

[0052] a second sub-coating 5, and the second sub-coating 5 is a Ta z Cr t B2 coating, where 0 ≤ z ≤ 1, 0 ≤ t ≤ 1, and 0.9 ≤ z + t ≤ 1.1;

[0053] a third sub-coating 6, and the third sub-coating 6 is a Cr a Ta b V c B2 coating, where 0 < a ≤ 1, 0 < b ≤ 0.4, 0 ≤ c ≤ 0.1, and 0.9 ≤ a + b + c ≤ 1.1; and

[0054] a CrB2 coating 7.

[0055] The present invention has the following advantages:

[0056] (1) The high-temperature self-lubricating and wear-resistant coating of the present invention is especially prepared by high-power pulsed magnetron sputtering process. The Ta metal bonding layer and TaN coating in the high-temperature wear-resistant coating have excellent bonding strength, which plays an important role in the bonding of the TaB x N y coating and the substrate.

[0057] (2) The first sub-coating (TaB x N yAs the coating thickness increases and the N2 flow rate gradually decreases, the y-value gradually decreases and the x-value gradually increases, forming TaB. x N y The gradient change of coating elements reduces stress concentration and provides extremely strong bonding strength to the TaN coating. Furthermore, TaN can maintain good coating properties even at high temperatures.

[0058] (3) The second sub-coating (Ta) in the high-temperature self-lubricating wear-resistant coating of the present invention z Cr t Similarly, with increasing coating thickness, the power value of the CrB2 target gradually increases until it becomes constant, while the power of the TaB2 target gradually decreases until it becomes constant, forming the Ta... z Cr t The elemental gradient of the B2 coating, when varied until constant, helps reduce the internal stress of the coating itself and improves its compatibility with TaB. x N y The bonding strength between coatings and Ta z Cr t The solid solution strengthening of Ta and Cr in the B2 coating improves the wear resistance of the coating.

[0059] (4) The third sub-coating (Cr) in the high-temperature self-lubricating wear-resistant coating of the present invention a Ta b V c In the B2 coating, the content of a increases with increasing coating thickness until it becomes constant, the content of b decreases with increasing thickness until it becomes constant, and the content of c increases with increasing thickness until it becomes constant. The content of V increases gradually until it stabilizes, which can improve its properties compared to Ta. z Cr t The bonding strength of the B2 coating. During cutting, V can generate V2O5, which has an extremely low coefficient of friction, significantly reducing built-up edge residue and improving tool life.

[0060] (5) The CrB2 coating in the high-temperature self-lubricating wear-resistant coating of the present invention has high hardness and low friction coefficient, which helps to improve the wear resistance of the tool and the surface quality of the workpiece.

[0061] (6) The high-temperature self-lubricating wear-resistant coating of the present invention does not easily form an affinity with high-temperature alloy materials, thus reducing the phenomenon of coating adhesion and peeling.

[0062] The technical solution of the present invention will be further described below with reference to specific embodiments.

[0063] Example 1

[0064] A high-temperature self-lubricating wear-resistant coated cutting tool, wherein the high-temperature self-lubricating wear-resistant coating is prepared by a high-power pulsed magnetron sputtering process, including the following steps:

[0065] S0. 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.

[0066] S1. Deposit a Ta binder layer on the substrate. The deposition process parameters are as follows:

[0067] The temperature was 650℃, the bias voltage was -200V, the Ta target sputtering power was 8000W, the pressure was 0.6Pa, and the deposition time was 480s.

[0068] S2. Deposit a TaN transition layer on the surface of the Ta binder layer. The deposition process parameters are as follows:

[0069] The temperature was 650℃, the bias voltage was -150V, the Ta target sputtering power was 8000W, the N2 flow rate was 300sccm, the pressure was 0.6Pa, and the deposition time was 960s.

[0070] S3. Deposit the first sub-coating (TaBN coating) on ​​the surface of the TaN transition layer. The deposition process parameters are as follows:

[0071] The temperature was 650℃, the bias voltage was -40V, the sputtering power of the TaB2 target was 4500W, the N2 flow rate gradually changed from 300sccm to 200sccm and remained constant, the pressure was 0.6Pa, and the deposition time was 3500s.

[0072] S4. Deposit a second sub-coating (Ta) on the surface of the first sub-coating. 0.5 Cr 0.5 B2 coating), deposition process parameters are:

[0073] The temperature was 650℃, the bias voltage was -60V, the sputtering power of the TaB2 target was gradually reduced from 4500W to 3000W and then kept constant, the sputtering power of the CrB2 target was gradually increased from 1000W to 3000W and then kept constant, the pressure was 0.6Pa, and the deposition time was 2000s.

[0074] S5, Deposit a third sub-coating (Cr) on the surface of the second sub-coating. 0.6 Ta 0.3 V 0.1 B2 coating), deposition process parameters are:

[0075] The temperature was 650℃, the bias voltage was -80V, the sputtering power of TaB2 target was gradually reduced from 3000W to 2000W and then kept constant, the sputtering power of CrB2 target was gradually increased from 3000W to 4500W and then kept constant, the sputtering power of V target was gradually increased from 1000W to 1800W and then kept constant, the pressure was 0.6Pa, and the deposition time was 16500s.

[0076] S6. Deposit a CrB2 coating on the surface of the third sub-coating; the deposition process parameters are as follows:

[0077] The temperature was 650℃, the bias voltage was -90V, the sputtering power of the CrB2 target was 4500W, the pressure was 0.6Pa, and the deposition time was 10000s.

[0078] S7. After the temperature drops to room temperature, the sample is taken out at room temperature to obtain the composite coated tool.

[0079] Example 2

[0080] A high-temperature self-lubricating wear-resistant coated cutting tool, wherein the high-temperature self-lubricating wear-resistant coating is prepared by a high-power pulsed magnetron sputtering process, including the following steps:

[0081] S0. 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.

[0082] S1. Deposit a Ta binder layer on the substrate. The deposition process parameters are as follows:

[0083] The temperature was 650℃, the bias voltage was -200V, the Ta target sputtering power was 8000W, the pressure was 0.6Pa, and the deposition time was 480s.

[0084] S2. Deposit a TaN transition layer on the surface of the Ta binder layer. The deposition process parameters are as follows:

[0085] The temperature was 650℃, the bias voltage was -150V, the Ta target sputtering power was 8000W, the N2 flow rate was 300sccm, the pressure was 0.6Pa, and the deposition time was 960s.

[0086] S3. Deposit the first sub-coating (TaBN coating) on ​​the surface of the TaN transition layer. The deposition process parameters are as follows:

[0087] The temperature was 650℃, the bias voltage was -40V, the sputtering power of the TaB2 target was 4500W, the N2 flow rate gradually changed from 300sccm to 200sccm and remained constant, the pressure was 0.6Pa, and the deposition time was 3500s.

[0088] S4. Deposit a second sub-coating (Ta) on the surface of the first sub-coating. 0.5 Cr 0.5 B2 coating), deposition process parameters are:

[0089] The temperature was 650℃, the bias voltage was -60V, the sputtering power of the TaB2 target was gradually reduced from 4500W to 3000W and then kept constant, the sputtering power of the CrB2 target was gradually increased from 1000W to 3000W and then kept constant, the pressure was 0.6Pa, and the deposition time was 2000s.

[0090] S5, Deposit a third sub-coating (Cr) on the surface of the second sub-coating. 0.6 Ta 0.325 V 0.075 B2 coating), deposition process parameters are:

[0091] The temperature was 650℃, the bias voltage was -80V, the sputtering power of TaB2 target was gradually reduced from 3000W to 2200W and then kept constant, the sputtering power of CrB2 target was gradually increased from 3000W to 4500W and then kept constant, the sputtering power of V target was gradually increased from 1000W to 1600W and then kept constant, the pressure was 0.6Pa, and the deposition time was 16500s.

[0092] S6. Deposit a CrB2 coating on the surface of the third sub-coating; the deposition process parameters are as follows:

[0093] The temperature was 650℃, the bias voltage was -90V, the sputtering power of the CrB2 target was 4500W, the pressure was 0.6Pa, and the deposition time was 10000s.

[0094] S7. After the temperature drops to room temperature, the sample is taken out at room temperature to obtain the composite coated tool.

[0095] Example 3

[0096] A high-temperature self-lubricating wear-resistant coated cutting tool, wherein the high-temperature self-lubricating wear-resistant coating is prepared by a high-power pulsed magnetron sputtering process, including the following steps:

[0097] S0. 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.

[0098] S1. Deposit a Ta binder layer on the substrate. The deposition process parameters are as follows:

[0099] The temperature was 650℃, the bias voltage was -200V, the Ta target sputtering power was 8000W, the pressure was 0.6Pa, and the deposition time was 480s.

[0100] S2. Deposit a TaN transition layer on the surface of the Ta binder layer. The deposition process parameters are as follows:

[0101] The temperature was 650℃, the bias voltage was -150V, the Ta target sputtering power was 8000W, the N2 flow rate was 300sccm, the pressure was 0.6Pa, and the deposition time was 960s.

[0102] S3. Deposit the first sub-coating (TaBN coating) on ​​the surface of the TaN transition layer. The deposition process parameters are as follows:

[0103] The temperature was 650℃, the bias voltage was -40V, the sputtering power of the TaB2 target was 4500W, the N2 flow rate gradually changed from 300sccm to 200sccm and remained constant, the pressure was 0.6Pa, and the deposition time was 3500s.

[0104] S4. Deposit a second sub-coating (Ta) on the surface of the first sub-coating. 0.5 Cr 0.5 B2 coating), deposition process parameters are:

[0105] The temperature was 650℃, the bias voltage was -60V, the sputtering power of the TaB2 target was gradually reduced from 4500W to 3000W and then kept constant, the sputtering power of the CrB2 target was gradually increased from 1000W to 3000W and then kept constant, the pressure was 0.6Pa, and the deposition time was 2000s.

[0106] S5, Deposit a third sub-coating (Cr) on the surface of the second sub-coating. 0.6 Ta 0.35 V 0.05 B2 coating); deposition process parameters are:

[0107] The temperature was 650℃, the bias voltage was -80V, the sputtering power of TaB2 target was gradually reduced from 3000W to 2400W and then kept constant, the sputtering power of CrB2 target was gradually increased from 3000W to 4500W and then kept constant, the sputtering power of V target was gradually increased from 1000W to 1400W and then kept constant, the pressure was 0.6Pa, and the deposition time was 16500s.

[0108] S6. Deposit a CrB2 coating on the surface of the third sub-coating; the deposition process parameters are as follows:

[0109] The temperature was 650℃, the bias voltage was -90V, the sputtering power of the CrB2 target was 4500W, the pressure was 0.6Pa, and the deposition time was 10000s.

[0110] S7. After the temperature drops to room temperature, the sample is taken out at room temperature to obtain the composite coated tool.

[0111] Example 4

[0112] A high-temperature self-lubricating wear-resistant coated cutting tool, wherein the high-temperature self-lubricating wear-resistant coating is prepared by a high-power pulsed magnetron sputtering process, including the following steps:

[0113] S0. 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.

[0114] S1. Deposit a Ta binder layer on the substrate. The deposition process parameters are as follows:

[0115] The temperature was 650℃, the bias voltage was -200V, the Ta target sputtering power was 8000W, the pressure was 0.6Pa, and the deposition time was 480s.

[0116] S2. Deposit a TaN transition layer on the surface of the Ta binder layer. The deposition process parameters are as follows:

[0117] The temperature was 650℃, the bias voltage was -150V, the Ta target sputtering power was 8000W, the N2 flow rate was 300sccm, the pressure was 0.6Pa, and the deposition time was 960s.

[0118] S3. Deposit the first sub-coating (TaBN coating) on ​​the surface of the TaN transition layer. The deposition process parameters are as follows:

[0119] The temperature was 650℃, the bias voltage was -40V, the sputtering power of the TaB2 target was 4500W, the N2 flow rate gradually changed from 300sccm to 200sccm and remained constant, the pressure was 0.6Pa, and the deposition time was 3500s.

[0120] S4. Deposit a second sub-coating (Ta) on the surface of the first sub-coating. 0.5 Cr 0.5 B2 coating), deposition process parameters are:

[0121] The temperature was 650℃, the bias voltage was -60V, the sputtering power of the TaB2 target was gradually reduced from 4500W to 3000W and then kept constant, the sputtering power of the CrB2 target was gradually increased from 1000W to 3000W and then kept constant, the pressure was 0.6Pa, and the deposition time was 2000s.

[0122] S5, Deposit a third sub-coating (Cr) on the surface of the second sub-coating. 0.6 Ta 0.375 V 0.025 B2 coating), deposition process parameters are:

[0123] The temperature was 650℃, the bias voltage was -80V, the sputtering power of TaB2 target was gradually reduced from 3000W to 2400W and then kept constant, the sputtering power of CrB2 target was gradually increased from 3000W to 4500W and then kept constant, the sputtering power of V target was gradually increased from 1000W to 1200W and then kept constant, the pressure was 0.6Pa, and the deposition time was 16500s.

[0124] S6. Deposit a CrB2 coating on the surface of the third sub-coating; the deposition process parameters are as follows:

[0125] The temperature was 650℃, the bias voltage was -90V, the sputtering power of the CrB2 target was 4500W, the pressure was 0.6Pa, and the deposition time was 10000s.

[0126] S7. After the temperature drops to room temperature, the sample is taken out at room temperature to obtain the composite coated tool.

[0127] Comparative Example 1

[0128] The difference from Example 1 is that steps S1-S2 are not performed, but the missing coating thickness will be increased in the first sub-coating (TaBN coating).

[0129] Comparative Example 2

[0130] The difference from Example 1 is that steps S3-S4 are omitted, but the missing coating thickness will be achieved in the third sub-coating (Cr). 0.6 Ta 0.3 V 0.1 B2 coating) increase.

[0131] Comparative Example 3

[0132] The difference from Example 1 is that step S5 is omitted, but the missing coating thickness will be increased in the CrB2 coating.

[0133] Comparative Example 4

[0134] The difference from Example 1 is that steps S3-S5 are omitted, but the missing coating thickness will be increased in the CrB2 coating.

[0135] The performance of the cutting tools prepared in each embodiment and comparative example was tested, and the results are shown in the table below.

[0136]

[0137] As can be seen from the table above, the high-temperature self-lubricating wear-resistant coated cutting tools prepared in the embodiments of this application have higher bonding strength than the comparative examples. This indicates that the transition layer in the coating significantly improves the film-substrate bonding strength, and the first and second sub-coatings improve the bonding force between films.

[0138] The cutting performance of the high-temperature wear-resistant coated tools prepared through the embodiments and comparative examples of this application is tested below, wherein:

[0139] The test conditions are as follows:

[0140] Material: Nickel-based alloy GH4169

[0141] Tool type: XNMU 070508-MM4

[0142] Cutting conditions: Cutting speed 65 m / min, feed rate 0.2 mm / z, depth of cut 1.5 mm

[0143] The results of the tool flank wear VB (unit mm) after cutting for different times are shown in the table below. The tool flank wear was measured using an OLYMPUS SZ61 optical ultra-depth-of-field microscope with a graduated scale.

[0144]

[0145] As can be seen from the table above (where "--" indicates that the tool has failed), under the same tool substrate and cutting conditions, the cutting performance of the high-temperature self-lubricating wear-resistant coated tool in this application embodiment is better than that of the comparative example.

[0146] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All 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 self-lubricating wear resistant coated cutting tool characterized by, The application relates to a high-temperature self-lubricating wear-resistant coating on a substrate. The high-temperature self-lubricating wear-resistant coating is prepared by a physical vapor deposition method and comprises, from the surface of the substrate outward, a Ta adhesive layer, a TaN transition layer and a CrB2 coating. In the thickness direction of the first sub-coating, the value of x increases with the increase of the thickness of the coating, and the value of y decreases with the increase of the thickness of the coating, so that a composition gradient of increasing B content and decreasing N content is formed in the first sub-coating. The first sub-coating comprises TaN nanocrystals and TaB2 nanocrystals, and the surfaces of the TaN nanocrystals and the TaB2 nanocrystals are at least partially covered by an amorphous BN layer. In the thickness direction of the second sub-coating, the value of t increases with the increase of the thickness of the coating, and the value of z decreases with the increase of the thickness of the coating, so that a composition gradient of increasing Cr content and decreasing Ta content is formed in the second sub-coating. a first sub-coating, the first sub-coating being TaB x N y a coating, wherein 0 < x < 2, 0 < y < 1; a second sub-coating, the second sub-coating being Ta z Cr t B2coating, wherein 0<z≤1, 0<t≤1, and 0.9<z+t≤1.1; a third sub-coating, the third sub-coating being Cr a Ta b V c B2coating, wherein 0 < a < 1, 0 < b < 0.4, 0 < c < 0.1, and 0.9 < a + b + c < 1.1; and In the thickness direction of the third sub-coating, the value of a increases with the increase of the thickness of the coating, the value of b decreases with the increase of the thickness of the coating, and the value of c gradually increases with the increase of the thickness of the coating, so that a composition gradient of increasing Cr content, decreasing Ta content and increasing V content is formed in the third sub-coating.

2. The high temperature self-lubricating wear resistant coated cutting tool of claim 1, wherein, The total thickness of the high-temperature self-lubricating wear-resistant coating is 1.5-6 mu m, wherein the thickness of the Ta adhesive layer is 0.05-0.1 mu m, the thickness of the TaN transition layer is 0.1-0.2 mu m, the thickness of the first sub-coating is 0.2-1 mu m, the thickness of the second sub-coating is 0.2-1.5 mu m, the thickness of the third sub-coating is 0.2-3 mu m, and the thickness of the CrB2 coating is 0.5-2 mu m.

3. The high temperature self-lubricating wear resistant coated cutting tool of claim 1, wherein, The grain size of the first sub-coating is 20-200 nm, the grain size of the second sub-coating is 20-100 nm, the grain size of the third sub-coating is 2-50 nm, and the grain size of the CrB2 coating is 2-25 nm.

4. The high temperature self-lubricating wear resistant coated cutting tool of claim 1 wherein, The Vickers hardness of the first sub-coating is 22-30 Ga, the Vickers hardness of the second sub-coating is 24-32 Ga, the Vickers hardness of the third sub-coating is 26-34 Ga, and the Vickers hardness of the CrB2 coating is 30-42 Ga.

5. The high temperature self-lubricating wear resistant coated cutting tool of claim 1 wherein, The coating is prepared by a high-power pulsed magnetron sputtering process, which comprises the following steps:

6. The high temperature self-lubricating wear resistant coated cutting tool of claim 1 wherein, S1, depositing a Ta adhesive layer on the substrate, and the deposition process parameters are as follows: a temperature of 600-750 DEG C, a bias voltage of -150 to -200 V, a Ta target sputtering power of 6000-8000 W, a pressure of 0.4-0.8 Pa; 7. The high temperature self-lubricating wear resistant coated cutting tool of claim 1 wherein, S2, depositing a TaN transition layer on the surface of the Ta adhesive layer, and the deposition process parameters are as follows: a temperature of 600-750 DEG C, a bias voltage of -100 to -150 V, a Ta target sputtering power of 6000-8000 W, an N2 flow rate of 200-300 sccm, a pressure of 0.4-0.8 Pa; 8. The high temperature self-lubricating wear resistant coated cutting tool of claim 1 wherein, S3, depositing a first sub-coating on the surface of the TaN transition layer, and the deposition process parameters are as follows:

9. A method of producing the high-temperature self-lubricating wear-resistant coated cutting tool according to any one of claims 1 to 8, characterized in that, ​ ​ ​ ​ ​ ​ The temperature is 600-750 DEG C, the bias is -40--100V, the TaB2 target sputtering power is 1000-4500W, the N2 flow is 0-300sccm, and the pressure is 0.4-0.8Pa; the N2 flow is gradually decreased during the deposition process; S4, depositing a second sub-coating on the surface of the first sub-coating; the deposition process parameters are: The temperature is 600-750 DEG C, the bias is -60--120V, the TaB2 target sputtering power is 1000-4500W, the CrB2 target sputtering power is 1000-4500W, and the pressure is 0.4-0.8Pa; the TaB2 target sputtering power is gradually decreased, and the CrB2 target sputtering power is gradually increased during the deposition process; S5, depositing a third sub-coating on the surface of the second sub-coating; the deposition process parameters are: The temperature is 600-750 DEG C, the bias is -80--120V, the TaB2 target sputtering power is 1000-4500W, the CrB2 target sputtering power is 1000-4500W, the V target sputtering power is 1000-6000W, and the pressure is 0.4-0.8Pa; the TaB2 target sputtering power is gradually decreased, the CrB2 target sputtering power is gradually increased, and the V target sputtering power is gradually increased during the deposition process; S6, depositing a CrB2 coating on the surface of the third sub-coating; the deposition process parameters are: The temperature is 600-750 DEG C, the bias is -80--120V, the CrB2 target sputtering power is 3000-4500W, and the pressure is 0.4-0.8Pa; S7, after the temperature is reduced to room temperature, the sample is taken out at room temperature, and a high-temperature self-lubricating wear-resistant coated cutting tool is obtained.

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