A multi-layer cyclic erosion-resistant and corrosion-resistant coating, its preparation method and application

Abstract

This invention discloses a multilayer cyclic erosion-resistant and corrosion-resistant coating, its preparation method, and its application, belonging to the field of coating material technology. This invention utilizes a magnetically filtered cathode vacuum arc coating system to prepare a multilayer cyclic high-performance erosion-resistant and corrosion-resistant coating. The coating consists of MeAl-MeAlN layers stacked sequentially from the inside out. 1‑x The invention comprises a MeAlN gradient bonding layer and at least one multi-layer target layer consisting of a MeAlN transition layer, a MeAl alloy soft layer, a MeAlN transition layer, and a MeAlSiN high-hardness layer, wherein Me can be any element selected from Ti, Cr, Zr, Hf, Nb, V, Mo, and Ta. This invention achieves a balance of high hardness, low stress, strong corrosion resistance, and erosion resistance, thereby significantly improving the impact and corrosion resistance of the material and providing technical support for achieving high performance and long service life of aero-engine compressor blades.

Description

Technical Field

[0001] This invention belongs to the field of coating materials technology, specifically relating to a multi-layer cyclic erosion-resistant and corrosion-resistant coating, its preparation method, and its application. Background Technology

[0002] When aircraft operate in dusty or coastal areas, sand particles, dust, salt spray, and other pollutants in the air are drawn into the aircraft engines by the high-speed airflow. In fact, once the engine ingests sand and dust, the sand and dust will cause erosion and wear on the compressor blades, while corrosive liquids such as salt spray will accelerate the erosion process of sand and dust. At the same time, sand and dust erosion will accelerate the salt spray corrosion process. Both continuously erode the compressor blades, damaging the engine performance from a structural and aerodynamic perspective, and in severe cases, even causing engine failure.

[0003] Protective coatings are an effective way to solve the problems of sand and dust erosion and salt spray corrosion on compressor blades. In the early stages of research, binary transition metal nitride ceramic coatings (TiN, CrN, ZrN, HfN, etc.) attracted much attention. However, binary ceramic coatings usually have a typical columnar crystal structure. On the one hand, corrosive media can penetrate into the coating through the gaps between the columnar crystals, accelerating the corrosion rate. On the other hand, under the high-speed impact of sand particles, the columnar crystals are prone to fracture.

[0004] To improve coating performance, domestic and international scholars have developed coating systems from binary coatings to multi-component composite coatings through alloying element doping. Among these, MeAlSiN coatings possess a unique nanocrystalline / amorphous microstructure, achieving a hardness as high as 40 GPa. Furthermore, their dense structure effectively prevents corrosive media from penetrating into the coating interior, thus giving MeAlSiN coatings broad application prospects in erosion and corrosion protection. However, the dense microstructure results in high internal stress in MeAlSiN coatings, making them prone to crack initiation under impact loads. Excessive internal stress can also reduce the film-substrate adhesion, limiting the coating's engineering applications. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a multi-layer cyclic erosion-resistant and corrosion-resistant coating, its preparation method and application, so as to solve the technical problems of high internal stress of the coating in the prior art, easy crack initiation under impact load, and low adhesion to the film substrate.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] This invention discloses a multi-sublayer cyclic erosion-resistant and corrosion-resistant coating, which is a composite coating consisting of a gradient adhesive layer and at least one set of multi-sublayer target layers;

[0008] The gradient adhesive layer consists of, from the inside out, a MeAl alloy phase and a subsaturated MeAlN phase.(1-x) The phase consists of nitrogen-saturated MeAlN phase, where 0 < x < 1, and the N element content in the gradient bonding layer gradually increases from 0 along the deposition thickness direction;

[0009] The target layer of the multi-sublayer structure consists of a MeAlN transition layer, a MeAl alloy soft layer, a MeAlN transition layer, and a MeAlSiN high-hardness layer, stacked sequentially from the inside out; Me is selected from any one of the following metallic elements: Ti, Cr, Zr, Hf, Nb, V, Mo, and Ta.

[0010] Preferably, the total thickness of the multi-layer cyclic high-performance erosion-resistant and corrosion-resistant coating is 10 μm to 100.0 μm, wherein the thickness of the gradient adhesive layer is 0.5 μm to 5.0 μm.

[0011] Preferably, in the multi-sublayer target layer, the layer thickness modulation ratio between the MeAlN transition layer, the MeAl alloy soft layer and the MeAlSiN high-hardness layer is 1:(0.2~2):(1~10), and the modulation period is 0.2μm~10.0μm.

[0012] This invention also discloses a method for preparing the above-mentioned multi-sublayer cyclic erosion-resistant and corrosion-resistant coating, comprising the following steps:

[0013] 1) Argon ion etching is performed on the substrate surface, and a gradient bonding layer is deposited on the etched substrate surface;

[0014] 2) Deposit a MeAlN transition layer on the surface of the gradient adhesive layer, deposit a MeAl alloy soft layer on the surface of the MeAlN transition layer, deposit a MeAlN transition layer on the surface of the MeAl alloy soft layer, and deposit a MeAlSiN high-hardness layer on the surface of the MeAlN transition layer.

[0015] 3) Repeat step 2) until the design requirements for the number of target layers in the multi-sublayer structure are met, and a multi-sublayer cyclic high-performance erosion-resistant and corrosion-resistant coating is obtained.

[0016] Preferably, the substrate is selected from titanium alloy, aluminum alloy, nickel-based alloy or stainless steel substrate; before argon ion etching, the substrate is first subjected to grinding, polishing, ultrasonic cleaning and drying treatment in sequence.

[0017] Preferably, in step 1), the argon ion etching process specifically involves: before etching, the vacuum level inside the coating cavity is less than 5 × 10⁻⁶. - 3 Pa, sample stage rotation speed is 5 to 10 rpm, substrate bias voltage is -500 to -800 V, etching current is 0.6 to 1.4 A, duty cycle is 40% to 60%, and etching time is 1200 to 1800 s;

[0018] In step 1), a gradient bonding layer is deposited on the etched substrate surface using a magnetic filter cathode vacuum arc coating system. The specific process parameters are as follows: the sample stage rotation speed is 5 to 10 rpm, the substrate bias voltage is -50 to -200V, the MeAl cathode target arc ignition current is 80 to 150A, and the nitrogen flow rate introduced into the vacuum coating chamber is linearly increased from 0 sccm to 20 to 200 sccm.

[0019] Preferably, in step 2), a MeAlN transition layer is deposited on the surface of the gradient adhesive layer. The specific process parameters are: the sample stage rotation speed is 5 to 10 rpm, the substrate bias voltage is -50 to -200V, the MeAl cathode target arc ignition current is 80 to 150A, and the nitrogen flow rate introduced into the vacuum coating chamber is 20 to 200 sccm.

[0020] A MeAl alloy soft layer was deposited on the surface of the MeAlN transition layer. The specific process parameters were: sample stage rotation speed of 5 to 10 rpm, substrate bias voltage of -50 to -200V, MeAl cathode target arc current of 80 to 150A, and nitrogen flow rate in the vacuum coating chamber of 0 sccm.

[0021] A MeAlN transition layer was deposited on the soft layer surface of MeAl alloy. The specific process parameters were: sample stage rotation speed of 5-10 rpm, substrate bias voltage of -50--200V, MeAl cathode target arc ignition current of 80-150A, and nitrogen flow rate in the vacuum coating chamber of 20-200sccm.

[0022] A high-hardness MeAlSiN layer was deposited on the surface of the MeAlN transition layer. The sample stage rotation speed was 5-10 rpm, the substrate bias voltage was -50 to -200 V, the arc ignition current of the MeAlSi cathode target was 80-150 A, and the nitrogen flow rate introduced into the vacuum coating chamber was 20-200 sccm.

[0023] Preferably, the atomic percentage of Me in the MeAl cathode target is 30% to 60%, and the atomic percentage of Al is 40% to 70%.

[0024] Preferably, the atomic percentage of Me in the MeAlSi cathode target is 25%–45%, the atomic percentage of Al is 35%–65%, and the atomic percentage of Si is 10%–20%.

[0025] The present invention also discloses the application of the above-mentioned multi-sublayer cyclic erosion-resistant and corrosion-resistant coating in the preparation of compressor blades.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The multi-layer cyclic erosion-resistant coating disclosed in this invention comprises MeAl-MeAlN layers stacked sequentially from the inside out. 1-x-MeAlN gradient bonding layer and at least one set of multi-sublayer target layers consisting of MeAlN transition layer, MeAl alloy soft layer, MeAlN transition layer and MeAlSiN high hardness layer, wherein Me can be any element selected from Ti, Cr, Zr, Hf, Nb, V, Mo and Ta. The gradient adhesive layer exhibits a gradual change in composition and physicochemical properties, which better connects the substrate and the target layer, thus enhancing the coating's adhesion. The MeAlSiN layer combines a dense nanocrystalline / amorphous microstructure with high hardness and mechanical properties, effectively resisting corrosion and low-angle abrasion from sand particles. The MeAl alloy soft layer can release internal stress in the coating, improve its toughness, and absorb the high-speed impact energy of sand particles. As a transition layer between the high-hardness MeAlSiN layer and the MeAl alloy soft layer, MeAlN can coordinate deformation, reduce interlayer stress concentration, and minimize interlayer cracking. Furthermore, the numerous interlayer interfaces in the multi-sublayer cyclic structure not only deflect cracks and slow down their propagation rate along the depth direction but also effectively block the penetration of corrosive media, further achieving high-performance erosion and corrosion resistance.

[0028] The specific advantages of this invention (which is also the inventive point of this invention) are reflected in:

[0029] First, the MeAlSiN layer possesses both a dense nanocrystalline / amorphous microstructure and high hardness, effectively resisting corrosion and low-angle abrasion from sand particles. The relatively soft MeAl metal layer reduces internal stress in the coating and absorbs the impact energy of sand particles, improving the coating's ability to resist high-angle impacts. However, the significant difference in properties between the high-hardness MeAlSiN layer and the soft MeAl layer makes them prone to interlayer cracking under sand impact. Therefore, this invention introduces a moderately hard MeAlN transition layer between the high-hardness MeAlSiN layer and the soft MeAl metal layer, forming a four-layer cyclic anti-erosion coating, unlike traditional bilayer cyclic multilayer coatings. The introduction of the MeAlN transition layer not only coordinates deformation, reduces internal stress in the coating, and minimizes interlayer cracking caused by mismatched layer interface deformation, but also significantly increases the number of interlayer interfaces while maintaining the same number of cycles. A large number of interlayer interfaces not only deflects crack propagation direction and slows crack propagation rate along the depth direction, improving the coating's erosion resistance, but also effectively blocks the penetration of corrosive media, further enhancing the coating's anti-corrosion performance.

[0030] Secondly, unlike traditional pure metal adhesive layers, this invention designs a gradient adhesive layer between the substrate and the target coating by controlling the nitrogen content in the deposition thickness direction. This layer consists of a MeAl alloy phase, a subsaturated MeAlN(1-x) phase, and a nitrogen-saturated MeAlN phase, arranged sequentially from the inside out. The composition and physicochemical properties of this adhesive layer change gradually, avoiding abrupt changes in composition and physicochemical properties at the film-substrate interface. This allows for better connection between the substrate and the bottommost MeAlN transition layer of the target layer, which helps to improve the adhesion and load-bearing capacity of the coating. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the multi-layer cyclic erosion-resistant and corrosion-resistant coating structure disclosed in this invention;

[0032] Figure 2 The diagram shows the comparison of residual stress results of the coatings in Examples 1-3 and Comparative Example 1 of the present invention;

[0033] Figure 3 This is a comparison of the scratch morphology of the coatings in Example 1 and Comparative Example 1 of the present invention;

[0034] Figure 4 This is a comparison diagram of the erosion resistance performance of the coatings in Example 1 and Comparative Example 1 of the present invention;

[0035] Figure 5 This is a comparison of the corrosion resistance performance of the coatings in Example 1 and Comparative Example 1 of the present invention. Detailed Implementation

[0036] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0037] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0038] The present invention will now be described in further detail with reference to the accompanying drawings:

[0039] First, combine with the appendix Figure 1 A brief description of the structure of the multi-sublayer cyclic erosion-resistant and corrosion-resistant coating proposed in this invention is provided. See also... Figure 1 The coating disclosed in this invention consists of MeAl-MeAlN layers stacked sequentially from the inside out. 1-x-MeAlN gradient bonding layer (gradient color layer in the figure), where 0 < x < 1, and at least one group of multi-sublayer target layers consisting of MeAlN transition layer (blue layer in the figure), MeAl alloy soft layer (light blue layer in the figure), MeAlN transition layer (blue layer in the figure) and MeAlSiN high hardness layer (dark blue layer in the figure).

[0040] Example 1

[0041] A method for preparing a high-performance erosion-resistant and corrosion-resistant TiAlSiN / TiAlN / TiAl / TiAlN multilayer cyclic coating on the surface of TC4 titanium alloy includes the following steps:

[0042] (1) Surface treatment of titanium alloy substrate

[0043] The surface of the titanium alloy substrate was ground and polished until its roughness was less than 0.1 μm; then, it was ultrasonically cleaned with acetone and anhydrous ethanol solution for 15 min each, and the substrate surface was dried with dry nitrogen gas.

[0044] (2) Argon ion etching

[0045] The cleaned titanium alloy substrate is mounted on the fixture of the magnetic filter cathode vacuum arc coating system, and the vacuum level is reduced to below 3 × 10⁻⁶. -3 At Pa, the bias voltage is set to -800V, the etching current is 1.0A, the duty cycle is 50%, and the etching time is 30min.

[0046] (3) Preparation of gradient adhesive layer

[0047] A magnetically filtered cathode vacuum arc deposition system was used to deposit TiAl-TiAlN on the etched surface of a titanium alloy substrate. 1-x -TiAlN gradient adhesive layer. Specific process parameters are as follows: sample stage rotation speed is 6 rpm, substrate bias voltage is -120V, TiAl cathode target arc ignition current is 100A, nitrogen flow rate in the vacuum coating chamber increases linearly from 0 sccm to 100 sccm with a function relationship of y = 2.5t (0 ≤ t ≤ 40), and adhesive layer deposition time is 40 min.

[0048] (4) Preparation of TiAlN transition layer on the surface of gradient adhesive layer

[0049] A magnetically filtered cathode vacuum arc coating system is used to coat TiAl-TiAlN. 1-x - A TiAlN transition layer is deposited on the surface of the TiAlN gradient binder. The specific process parameters are as follows: the sample stage rotation speed is kept at 6 rpm, the substrate bias voltage is -120V, the arc initiation current of the TiAl cathode target is 100A, the nitrogen flow rate in the vacuum deposition chamber is kept at 100 sccm, and the deposition time is 20 min.

[0050] (5) Preparation of TiAl alloy soft layer on the surface of TiAlN transition layer

[0051] A magnetically filtered cathode vacuum arc deposition system was used to deposit a TiAl alloy soft layer on the surface of the TiAlN transition layer. The specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the arc initiation current of the TiAl cathode target was 100A, the nitrogen gas inlet switch was turned off, and the deposition time was 20 min.

[0052] (6) Preparation of TiAlN transition layer on the surface of TiAl alloy soft layer

[0053] A magnetically filtered cathode vacuum arc deposition system was used to deposit a TiAlN transition layer on the surface of a TiAl alloy soft layer. The specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the arc initiation current of the TiAl cathode target was 100A, the nitrogen gas inlet switch was turned on, and the nitrogen gas flow rate into the vacuum deposition chamber was 100 sccm, with a deposition time of 20 min.

[0054] (7) Preparation of TiAlSiN high-hardness layer on the surface of TiAlN transition layer

[0055] A magnetically filtered cathode vacuum arc deposition system was used to deposit a TiAlSiN high-hardness layer on the surface of the TiAlN transition layer. Specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the nitrogen flow rate into the vacuum deposition chamber was 100 sccm, the arc initiation current of the TiAl cathode target was cut off, while the arc initiation current of the TiAlSi cathode target was set to 120A, and the deposition time was 60 min.

[0056] Steps (4) to (7) are executed sequentially for a total of 3 times to obtain a TiAlSiN / TiAlN / TiAl / TiAlN multi-sublayer cyclic high-performance anti-erosion and corrosion-resistant coating with a total thickness of approximately 20 μm.

[0057] Example 2

[0058] A method for preparing a high-performance erosion-resistant and corrosion-resistant coating with CrAlSiN / CrAlN / CrAl / CrAlN multilayer cyclic coating on the surface of TC4 titanium alloy includes the following steps:

[0059] (1) Surface treatment of titanium alloy substrate

[0060] The surface of the titanium alloy substrate was ground and polished until its roughness was less than 0.1 μm; then, it was ultrasonically cleaned with acetone and anhydrous ethanol solution for 15 min each, and the substrate surface was dried with dry nitrogen gas.

[0061] (2) Argon ion etching

[0062] The cleaned titanium alloy substrate is mounted on the fixture of the magnetic filter cathode vacuum arc coating system, and the vacuum level is reduced to below 3 × 10⁻⁶. -3 At Pa, the bias voltage is set to -800V, the etching current is 1.0A, the duty cycle is 50%, and the etching time is 30min.

[0063] (3) Preparation of gradient adhesive layer

[0064] A magnetically filtered cathode vacuum arc deposition system is used to deposit CrAl-CrAlN on the etched surface of a titanium alloy substrate. 1-x -CrAlN gradient adhesive layer. Specific process parameters are as follows: sample stage rotation speed is 6 rpm, substrate bias voltage is -120V, CrAl cathode target arc ignition current is 110A, nitrogen flow rate in the vacuum coating chamber increases linearly from 0 sccm to 100 sccm with a function relationship of y = 2.5t (0 ≤ t ≤ 40), and adhesive layer deposition time is 40 min.

[0065] (4) Preparation of CrAlN transition layer on the surface of gradient adhesive layer

[0066] A magnetically filtered cathode vacuum arc coating system is used in the CrAl-CrAlN coating process. 1-x - A CrAlN transition layer is deposited on the surface of the CrAlN gradient adhesive layer. The specific process parameters are as follows: the sample stage rotation speed is maintained at 6 rpm, the substrate bias voltage is -120V, the arc initiation current of the CrAl cathode target is 110A, the nitrogen flow rate in the vacuum coating chamber is maintained at 100 sccm, and the deposition time is 20 min.

[0067] (5) Preparation of CrAl alloy soft layer on the surface of CrAlN transition layer

[0068] A magnetically filtered cathode vacuum arc deposition system was used to deposit a CrAl alloy soft layer on the surface of the CrAlN transition layer. The specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the CrAl cathode target arc initiation current was 110A, the nitrogen gas inlet switch was turned off, and the deposition time was 20 min.

[0069] (6) Preparation of CrAlN transition layer on the surface of CrAl alloy soft layer

[0070] A magnetically filtered cathode vacuum arc deposition system was used to deposit a CrAlN transition layer on the surface of a CrAl alloy soft layer. The specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the arc initiation current of the CrAl cathode target was 110A, the nitrogen gas inlet switch was turned on, and the nitrogen gas flow rate into the vacuum deposition chamber was 100 sccm. The deposition time was 20 min.

[0071] (7) Preparation of CrAlSiN high-hardness layer on the surface of CrAlN transition layer

[0072] A magnetically filtered cathode vacuum arc deposition system was used to deposit a CrAlSiN high-hardness layer on the surface of the CrAlN transition layer. Specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the nitrogen flow rate into the vacuum deposition chamber was 100 sccm, the arc initiation current of the CrAl cathode target was cut off, while the arc initiation current of the CrAlSi cathode target was set to 120A, and the deposition time was 60 min.

[0073] Steps (4) to (7) are executed sequentially for a total of 3 times to obtain a high-performance anti-erosion coating with a total thickness of approximately 20 μm, consisting of multiple sublayers of CrAlSiN / CrAlN / CrAl / CrAlN.

[0074] Example 3

[0075] A method for preparing a high-performance erosion-resistant and corrosion-resistant ZrAlSiN / ZrAlN / ZrAl / ZrAlN multilayer cyclic coating on the surface of TC4 titanium alloy includes the following steps:

[0076] (1) Surface treatment of titanium alloy substrate

[0077] The surface of the titanium alloy substrate was ground and polished until its roughness was less than 0.1 μm; then, it was ultrasonically cleaned with acetone and anhydrous ethanol solution for 15 min each, and the substrate surface was dried with dry nitrogen gas.

[0078] (2) Argon ion etching

[0079] The cleaned titanium alloy substrate is mounted on the fixture of the magnetic filter cathode vacuum arc coating system, and the vacuum level is reduced to below 3 × 10⁻⁶. -3 At Pa, the bias voltage is set to -800V, the etching current is 1.0A, the duty cycle is 50%, and the etching time is 30min.

[0080] (3) Preparation of gradient adhesive layer

[0081] A magnetically filtered cathode vacuum arc deposition system was used to deposit ZrAl-ZrAlN on the etched surface of a titanium alloy substrate. 1-x -ZrAlN gradient adhesive layer. Specific process parameters are as follows: sample stage rotation speed is 6 rpm, substrate bias voltage is -120V, ZrAl cathode target arc initiation current is 110A, nitrogen flow rate in the vacuum coating chamber increases linearly from 0 sccm to 100 sccm with a function relationship of y = 2.5t (0 ≤ t ≤ 40), and adhesive layer deposition time is 40 min.

[0082] (4) Preparation of ZrAlN transition layer on the surface of gradient adhesive layer

[0083] A magnetically filtered cathode vacuum arc coating system is used in the ZrAl-ZrAlN coating process. 1-x - A ZrAlN transition layer is deposited on the surface of the ZrAlN gradient adhesive layer. The specific process parameters are as follows: the sample stage rotation speed is maintained at 6 rpm, the substrate bias voltage is -120V, the ZrAl cathode target arc initiation current is 100A, the nitrogen flow rate in the vacuum coating chamber is maintained at 100 sccm, and the deposition time is 20 min.

[0084] (5) Preparation of ZrAl alloy soft layer on the surface of ZrAlN transition layer

[0085] A magnetically filtered cathode vacuum arc deposition system was used to deposit a ZrAl alloy soft layer on the surface of the ZrAlN transition layer. The specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the ZrAl cathode target arc initiation current was 100A, the nitrogen gas inlet switch was turned off, and the deposition time was 20 min.

[0086] (6) Preparation of ZrAlN transition layer on ZrAl alloy soft layer surface

[0087] A magnetically filtered cathode vacuum arc deposition system was used to deposit a ZrAlN transition layer on the surface of a ZrAl alloy soft layer. The specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the ZrAl cathode target arc initiation current was 100A, the nitrogen inlet switch was turned on, and the nitrogen flow rate into the vacuum deposition chamber was 100 sccm. The deposition time was 20 min.

[0088] (7) Preparation of ZrAlSiN high-hardness layer on the surface of ZrAlN transition layer

[0089] A magnetically filtered cathode vacuum arc deposition system was used to deposit a ZrAlSiN high-hardness layer on the surface of the ZrAlN transition layer. Specific process parameters were as follows: the sample stage rotation speed was maintained at 6 rpm, the substrate bias voltage was -120V, the nitrogen flow rate into the vacuum deposition chamber was 100 sccm, the arc initiation current of the ZrAl cathode target was cut off, and the arc initiation current of the ZrAlSi cathode target was set to 120A. The deposition time was 60 min.

[0090] Steps (4) to (7) are executed sequentially for a total of 3 times to obtain a ZrAlSiN / ZrAlN / ZrAl / ZrAlN multi-sublayer cyclic high-performance anti-erosion and corrosion-resistant coating with a total thickness of approximately 20 μm.

[0091] Comparative Example 1

[0092] A method for preparing a TiAlSiN coating on the surface of TC4 titanium alloy includes the following steps:

[0093] (1) Surface treatment of titanium alloy substrate

[0094] The surface of the titanium alloy substrate was ground and polished until its roughness was less than 0.1 μm; then, it was ultrasonically cleaned with acetone and anhydrous ethanol solution for 15 min each, and the substrate surface was dried with dry nitrogen gas.

[0095] (2) Argon ion etching

[0096] The cleaned titanium alloy substrate is mounted on the fixture of the magnetic filter cathode vacuum arc coating system, and the vacuum level is reduced to below 3 × 10⁻⁶. -3 At Pa, the bias voltage is set to -800V, the etching current is 1.0A, the duty cycle is 50%, and the etching time is 30min.

[0097] (3) Preparation of TiAlSi adhesive layer

[0098] A magnetically filtered cathode vacuum arc deposition system was used to deposit a TiAlSi binder layer on the etched surface of a titanium alloy substrate. The specific process parameters were: stage rotation speed of 6 rpm, substrate bias voltage of -120V, TiAlSi cathode target arc initiation current of 100A, and binder layer deposition time of 40 min.

[0099] (4) Preparation of TiAlSiN coating

[0100] A TiAlSiN coating was deposited on the adhesive layer surface using a magnetically filtered cathode vacuum arc deposition system. Specific process parameters were as follows: stage rotation speed of 6 rpm, substrate bias voltage of -120 V, TiAlSi cathode target arc initiation current of 100 A, nitrogen gas flow rate of 100 sccm introduced into the vacuum deposition chamber, and deposition time of 360 min. A TiAlSiN coating with a total thickness of approximately 20 μm was obtained.

[0101] Figure 2 The diagram shows a comparison of residual stress in the coatings of each embodiment and the comparative example. The results show that the residual stress in the coatings of the three embodiments is significantly reduced compared to the comparative example coating. Furthermore, Figure 3 The image shows a comparison of the scratch morphology of the coatings in Example 1 and Comparative Example 1. Using the same scratch test method and parameters, the results show that there is no obvious brittle spalling near the scratch trajectory of the coating in Example 1, while a large area of ​​coating spalling occurred near the scratch trajectory of the coating in Comparative Example 1. This indicates that the multi-sublayer cyclic structure disclosed in this invention can significantly improve the poor toughness problem of TiAlSiN coatings caused by excessive internal stress. In addition, the scratch test results show that the Lc3 adhesion of the coating in Example 1 is significantly better than that of the coating in Comparative Example 1, indicating that the gradient adhesive layer disclosed in this invention can effectively improve the film-substrate bonding strength of hard coatings.

[0102] Figure 4The figures show the damage morphology of the coatings in Example 1 and Comparative Example 1 after 20 minutes of sand and dust erosion. The results show that the coating surface of Example 1 suffered slight erosion damage, manifested as small-area coating peeling; however, the coating in the eroded area of ​​the coating in Comparative Example 1 was almost completely peeled off, and a large area of ​​the substrate was severely eroded, indicating that the multi-sublayer cyclic structure coating disclosed in this invention has excellent erosion resistance.

[0103] Figure 5 The image shows the coating I of Example 1 and Comparative Example 1. corr Comparison. Using the same corrosive solution and test parameters, the results show that Comparative Example 1's I... corr 18.1×10 -7 A / cm 2 Example 1 Coating I corr 4.37×10 -7 A / cm 2 The corrosion resistance was reduced by 75.9%, indicating that Example 1 of the present invention has significantly better corrosion resistance.

[0104] In summary, the coating disclosed in this invention consists of MeAl-MeAlN layers stacked sequentially from the inside out. 1-x - A MeAlN gradient adhesive layer and at least one set of multi-sublayer target layers consisting of a MeAlN transition layer, a MeAl alloy soft layer, a MeAlN transition layer and a MeAlSiN high-hardness layer. The gradient adhesive layer and the multi-sublayer cyclic structure effectively improve the internal stress and toughness matching of MeAlSiN-type coatings, and significantly enhance the coating's adhesion and erosion and corrosion resistance.

[0105] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A multi-layer cyclic erosion-resistant and corrosion-resistant coating, characterized in that, A composite coating consisting of a gradient adhesive layer and at least one set of multi-sublayer target layers; The gradient adhesive layer consists of, from the inside out, a MeAl alloy phase and a subsaturated MeAlN phase. (1-x) The phase consists of nitrogen-saturated MeAlN phase, where 0 < x < 1, and the N element content in the gradient bonding layer gradually increases from 0 along the deposition thickness direction; The target layer of the multi-sublayer structure consists of a MeAlN transition layer, a MeAl alloy soft layer, a MeAlN transition layer, and a MeAlSiN high-hardness layer, stacked sequentially from the inside out; Me is selected from any one of the following metal elements: Ti, Cr, Zr, Hf, Nb, V, Mo, and Ta; the layer thickness modulation ratio between the MeAlN transition layer, the MeAl alloy soft layer, and the MeAlSiN high-hardness layer is 1:(0.2~2):(1~10), and the modulation period is 0.2 μm~10.0 μm; The total thickness of the multi-layer cyclic erosion-resistant and corrosion-resistant coating is 10 μm to 100.0 μm, of which the thickness of the gradient adhesive layer is 0.5 μm to 5.0 μm.

2. The method for preparing the multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 1, characterized in that, Includes the following steps: 1) Argon ion etching is performed on the substrate surface, and a gradient bonding layer is deposited on the etched substrate surface; 2) Deposit a MeAlN transition layer on the surface of the gradient adhesive layer, deposit a MeAl alloy soft layer on the surface of the MeAlN transition layer, deposit a MeAlN transition layer on the surface of the MeAl alloy soft layer, and deposit a MeAlSiN high-hardness layer on the surface of the MeAlN transition layer. 3) Repeat step 2) until the design requirements for the number of target layers in the multi-sublayer structure are met, and a multi-sublayer cyclic erosion-resistant and corrosion-resistant coating is obtained.

3. The method for preparing a multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 2, characterized in that, The substrate is selected from titanium alloy, aluminum alloy, nickel-based alloy or stainless steel substrate; before argon ion etching, the substrate is first subjected to grinding, polishing, ultrasonic cleaning and drying treatment in sequence.

4. The method for preparing the multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 2, characterized in that, In step 1), the specific process of argon ion etching is as follows: before etching, the vacuum degree in the coating cavity is less than 5 × 10⁻⁶. -3 Pa, stage speed 5~10 rpm, substrate bias voltage -500~-800 V, etching current 0.6~1.4 A, duty cycle 40%~60%, etching time 1200~1800 s.

5. The method for preparing the multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 2, characterized in that, In step 1), a gradient bonding layer is deposited on the etched substrate surface using a magnetic filter cathode vacuum arc coating system. The specific process parameters are as follows: the sample stage rotation speed is 5~10 rpm, the substrate bias voltage is -50~-200 V, the MeAl cathode target arc ignition current is 80~150 A, and the nitrogen flow rate introduced into the vacuum coating chamber is linearly increased from 0 sccm to 20~200 sccm.

6. The method for preparing the multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 2, characterized in that, In step 2), a MeAlN transition layer is deposited on the surface of the gradient adhesive layer. The specific process parameters are: the sample stage rotation speed is 5~10 rpm, the substrate bias voltage is -50 ~ -200 V, the MeAl cathode target arc ignition current is 80 ~150 A, and the nitrogen flow rate introduced into the vacuum coating chamber is 20~200 sccm. A MeAl alloy soft layer was deposited on the surface of the MeAlN transition layer. The specific process parameters were: sample stage rotation speed of 5~10 rpm, substrate bias voltage of -50 ~ -200 V, MeAl cathode target arc ignition current of 80 ~150 A, and nitrogen flow rate in the vacuum coating chamber of 0 sccm. A MeAlN transition layer was deposited on the soft surface of the MeAl alloy. The specific process parameters were: sample stage rotation speed of 5~10 rpm, substrate bias voltage of -50 ~ -200 V, MeAl cathode target arc ignition current of 80 ~150 A, and nitrogen flow rate in the vacuum coating chamber of 20~200 sccm. A high-hardness MeAlSiN layer was deposited on the surface of the MeAlN transition layer. The sample stage rotation speed was 5~10 rpm, the substrate bias voltage was -50~-200V, the arc ignition current of the MeAlSi cathode target was 80~150 A, and the nitrogen flow rate introduced into the vacuum coating chamber was 20~200 sccm.

7. The method for preparing a multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 6, characterized in that, In a MeAl cathode target, the atomic percentage of Me is 30%~60% and the atomic percentage of Al is 40%~70%; in a MeAlSi cathode target, the atomic percentage of Me is 25%~45%, the atomic percentage of Al is 35%~65%, and the atomic percentage of Si is 10%~20%.

8. The application of the multi-layer cyclic erosion-resistant and corrosion-resistant coating according to claim 1 in the preparation of compressor blades.

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