Method for improving corrosion resistance and corrosion and wear resistance of titanium alloy surface by forming self-repairing thick film in situ

Abstract

The invention belongs to the technical field of surface functional coatings, and particularly relates to a method for improving corrosion resistance and corrosion and wear resistance of a titanium alloy surface by forming a self-repairing thick film in situ. The method is based on a multi-arc ion plating technology, nitrogen and oxygen are alternately introduced in the deposition process, and the nanometer multilayer coating of a ZrO2 / ZrN periodic layered structure is constructed on the surface of a titanium alloy matrix. By regulating and controlling the oxygen flow (500-800 sccm), a low-oxygen coating and a high-oxygen coating can be obtained, and accurate regulation and control of the tissue structure and the surface reaction behavior of the film can be realized. According to the formed ZrO2 / ZrN multi-layer structure, the compactness and the structure uniformity of the coating are remarkably improved, meanwhile, continuous growth of columnar crystals is effectively inhibited through a lattice mismatch interface between ZrO2 and ZrN, and a rapid permeation path of a corrosive medium is blocked. Compared with a traditional ZrN single-layer coating, the multi-layer structure has the advantage that the electrochemical stability, the interface protection capability and the corrosive wear resistance in a simulated corrosion environment are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of coating applications, and particularly relates to a method for improving the corrosion resistance and corrosion wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film. Background Art

[0002] Bone implant materials have undergone significant progress in the past few decades and can be roughly classified into four categories according to the nature of the materials used in manufacturing: metals and alloys, ceramics, polymers, and composites. Titanium alloys have become the most commonly used medical implant materials at present due to their low elastic modulus, excellent corrosion resistance, and biocompatibility, and are widely used in the treatment of orthopedic injuries such as artificial joints, intramedullary nails, bone plates, cervical / lumbar interbody fusion devices, etc. In addition, titanium and its alloys also have relatively wide applications in the fields of cardiac / vascular intervention, dental implants, prosthetic wheelchairs, etc. However, while titanium alloys are corroded by body fluids in the human body environment, they also face reciprocating friction between bone implants. Under the combined influence of corrosion and friction, the surface of the titanium alloy is severely damaged. Therefore, in view of the practical significance of the safe use of titanium alloys in the human body, it is very important to improve their corrosion resistance and friction resistance.

[0003] At present, preparing a hard coating on the surface of titanium alloys is one of the most effective methods to solve the problems of low surface hardness and poor wear resistance of titanium alloys. As a metal with no biological toxicity, good corrosion resistance, and good cell compatibility, Zr has been widely used in biomedicine. The ZrN coating prepared by physical vapor deposition (PVD) technology performs well in practical applications. However, under the combined action of a corrosive medium and a load, the ZrN coating prepared by PVD gradually thins and finally fails, and cannot provide long-term protection.

[0004] In view of the above defects, the creators of the present invention have finally obtained the present invention through long-term research and practice. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem that the protective coating gradually thins and has poor protective performance under the combined action of a corrosive medium and a load on the ZrN coating on the surface of titanium alloys, and provides a method for improving the corrosion resistance and corrosion wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film.

[0006] To achieve the above purpose, the present invention discloses a method for improving the corrosion resistance and corrosion wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film, including the following steps:

[0007] S1, ultrasonically clean and dry the titanium alloy sample;

[0008] S2. Place the processed titanium alloy sample in step S1 on the substrate turntable. After heating and evacuating, introduce argon gas, turn on the Ti target, perform ion bombardment on the substrate surface, ion-etch and clean the substrate surface, and simultaneously activate the substrate.

[0009] S3. After the ion etching in step S2 ends, keep the deposition temperature and the pressure in the furnace chamber unchanged, turn on the Zr target, and deposit a metal Zr layer.

[0010] S4. After the Zr metal layer deposition in step S3 is completed, keep the deposition temperature unchanged, turn off the argon gas, introduce oxygen gas, and deposit a ZrO2 thin film.

[0011] S5. After the ZrO2 thin film deposition in step S4 ends, keep the deposition temperature unchanged, turn off the oxygen gas, introduce nitrogen gas, and deposit a ZrN thin film.

[0012] S6. Repeat steps S5 - S6 to alternately deposit ZrO2 layers and ZrN layers to obtain a titanium alloy with a ZrO2 / ZrN nano-multilayer coating on its surface.

[0013] In step S2, the argon gas flow rate is 250 - 550 sccm, the substrate negative bias voltage is -150 V, and the ion etching time is 50 min.

[0014] In step S3, the substrate bias voltage is -60 - -80 V, the target current of the metal Zr target is 110 - 140 A, and the deposition time is 5 - 10 min.

[0015] In step S4, the pressure after introducing nitrogen gas is 1 - 2 Pa, the nitrogen gas flow rate is 100 - 300 sccm, and the deposition time is 2 - 4 min.

[0016] In step S5, the pressure after introducing oxygen gas is 3 - 5 Pa, the O2 flow rate is 500 - 800 sccm, and the deposition time is 2 - 5 min.

[0017] In step S6, the pressure after introducing nitrogen gas is 2 - 4 Pa, the N2 flow rate is 400 - 800 sccm, and the deposition time is 3 - 6 min.

[0018] In step S6, the ZrO2 / ZrN nano-multilayer coating includes multiple ZrO2 / ZrN coating units. The ZrO2 / ZrN coating unit includes an oxygen-containing ZrO2 layer and a nitrogen-containing ZrN layer. The thickness of the ZrO2 layer is 10 nm, the thickness of the ZrN layer is 20 nm, and the thickness of the ZrO2 / ZrN coating unit is 30 nm.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The O element can promote the grain refinement of the nitride coating, form a dense microstructure, and improve the corrosion resistance of the coating.

[0021] 2. The highly mismatched semi-coherent interface between ZrO2 and ZrN can effectively reduce the "corrosion channels", delay the diffusion of corrosive media in the coating, and thus improve the corrosion resistance of the ZrO2 / ZrN nanomultilayer coating.

[0022] 3. The ultra-thin ZrO2 nanolayer in the coating can be transformed into an amorphous phase during the wear process. At the same time, under the action of friction force, it wraps the hard crystal phase. The amorphous-wrapped nanocrystal structure provides additional bonding force, in-situ forming a thick and dense friction oxidation film, which improves the corrosion and wear resistance of the coating. Description of the Drawings

[0023] Figure 1 (a) is the cross-sectional FESEM image of the ZrN multilayer coating. Figure 1 (b) is the cross-sectional FESEM image of the ZrON-1 multilayer coating. Figure 1 (c) is the cross-sectional FESEM image of the ZrON-2 multilayer coating.

[0024] Figure 2 are the XRD patterns of the ZrN, ZrON-1, and ZrON-2 coatings.

[0025] Figure 3 is the TEM image of the (a) ZrON-2 coating. Figure 3 (b) is Figure 3 the enlarged image of region B in (a).

[0026] Figure 4 are the impedance spectra of the ZrN, ZrON-1, and ZrON-2 coatings.

[0027] Figure 5 are the potentiodynamic polarization curves of the ZrN, ZrON-1, and ZrON-2 coatings.

[0028] Figure 6 are in the corrosion and friction experiments of the ZrN, ZrON-1, and ZrON-2 coatings: (a) open circuit potential and (b) friction coefficient.

[0029] Figure 7 are the average friction coefficients and wear rates of the ZrN, ZrON-1, and ZrON-2 coatings after corrosion and friction.

[0030] Figure 8Surface morphologies of the wear tracks after corrosion and friction for ZrN, ZrON-1, and ZrON-2 coatings: (a) ZrN coating, (a’) enlarged image of Fig. (a), (b) ZrON-1 coating, (b’) enlarged image of Fig. (b), (c) ZrON-2 coating, (c’) enlarged image of Fig. (c);

[0031] Figure 9 Cross-sectional morphologies of the wear tracks after corrosion and friction for ZrN, ZrON-1, and ZrON-2 coatings: (a) ZrN coating, (a’) enlarged image of Fig. (a), (b) ZrON-1 coating, (b’) enlarged image of Fig. (b), (c) ZrON-2 coating, (c’) enlarged image of Fig. (c). Detailed implementation manners

[0032] The following further elaborates on the above and additional technical features and advantages of the present invention in conjunction with the accompanying drawings.

[0033] Example 1

[0034] (1) The polished Ti-6Al-4V titanium alloy material was ultrasonically cleaned for 10 minutes, rinsed with deionized water, and dried for later use;

[0035] (2) The treated titanium alloy sample was placed on the substrate turntable, heated to 400 °C, evacuated to 10 -4 Pa, Ar gas was introduced with a flow rate of 380 sccm, the Ti target was turned on, the negative bias voltage was controlled at -150 V, and ion bombardment etching cleaning was carried out for 50 min;

[0036] (3) While maintaining the deposition temperature, the Zr target was turned on to deposit a metallic Zr layer; under the conditions of a substrate bias of -70 and a target current of the metallic Zr target of 130 A, the deposition was completed after 8 min.

[0037] (4) While maintaining the deposition temperature, N2 gas was further increased, the pressure was changed to 2 Pa, the N2 flow rate was 300 sccm, and the ZrN layer was deposited. The deposition time was 110 min, and the deposition of the ZrN layer was completed.

[0038] Example 2

[0039] (1) The polished Ti-6Al-4V titanium alloy material was ultrasonically cleaned for 10 minutes, rinsed with deionized water, and dried for later use;

[0040] (2) The treated titanium alloy sample was placed on the substrate turntable, heated to 400 °C, evacuated to 10 -4Introduce Ar gas at a flow rate of 380 sccm. Turn on the Ti target, control the negative bias voltage at -150 V, and perform ion bombardment etching and cleaning for 50 minutes.

[0041] (3) Maintain the deposition temperature, turn on the Zr target, and deposit a metal Zr layer. Under the conditions of a substrate bias of -70 and a target current of 130 A for the metal Zr target, the deposition is completed after 8 minutes.

[0042] (4) Keep the deposition temperature and the target current of the Zr target unchanged. Turn off the argon gas, introduce oxygen, increase the O2 gas flow rate to 500 sccm, change the pressure to 3 Pa, and deposit a ZrO2 nano-multilayer for 2 minutes. Then turn off the oxygen, introduce nitrogen, change the pressure to 4 Pa, and deposit for 4 minutes with an N2 flow rate of 700 sccm. Repeat this process multiple times to deposit a ZrO2 / ZrN nano-multilayer coating (referred to as the ZrON-1 coating) for 90 minutes.

[0043] Example 3

[0044] (1) Ultrasonically clean the polished Ti-6Al-4V titanium alloy material for 10 minutes, rinse it with deionized water, and dry the sample for later use.

[0045] (2) Place the treated titanium alloy sample on the substrate turntable, heat it to 400 °C, and evacuate to 10 -4 Pa, introduce Ar gas at a flow rate of 380 sccm. Turn on the Ti target, control the negative bias voltage at -150 V, and perform ion bombardment etching and cleaning for 50 minutes.

[0046] (3) Maintain the deposition temperature, turn on the Zr target, and deposit a metal Zr layer. Under the conditions of a substrate bias of -70 and a target current of 130 A for the metal Zr target, the deposition is completed after 8 minutes.

[0047] (4) Keep the deposition temperature and the target current of the Zr target unchanged. Turn off the argon gas, introduce oxygen, increase the O2 gas flow rate to 800 sccm, change the pressure to 5 Pa, and deposit a ZrO2 nano-multilayer for 2 minutes. Then turn off the oxygen, introduce nitrogen, change the pressure to 4 Pa, and deposit for 4 minutes with an N2 flow rate of 700 sccm. Repeat this process multiple times to deposit a ZrO2 / ZrN nano-multilayer coating (referred to as the ZrON-2 coating) for 90 minutes.

[0048] Figure 1 (a) is the cross-sectional FE-SEM image of the ZrN multi-layer coating. A typical columnar crystal growth structure can be observed. There are obvious large particle defects in the coating, and the interface structure is relatively loose. Figure 1(b) Cross-sectional image of the ZrON-1 multilayer coating prepared by low oxygen doping, indicating that the introduction of oxygen effectively interrupts the growth of columnar crystals, forms a relatively uniform microstructure, has fewer defects, and significantly improves the densification; Figure 1 (c) The ZrON-2 multilayer coating prepared by high oxygen doping has a more homogeneous non-columnar structure, with clear interlayer interfaces and the strongest structural continuity, showing the best densification and stability.

[0049] Figure 2 X-ray diffraction (XRD) patterns of ZrN, ZrON-1, and ZrON-2 coatings are shown. In the ZrN coating, typical diffraction peaks of crystal planes such as ZrN(111), (200), and (220) can be observed. With the introduction of oxygen, diffraction peaks of ZrO2 appear in the ZrON-1 coating, indicating that part of Zr undergoes an oxidation reaction to form zirconia phase, but the ZrN characteristic peaks still remain intact, indicating that the crystal structure is still mainly ZrN at this time and there is no obvious preferred orientation change. Under high oxygen flux conditions, the ZrN(200) peak in the ZrON-2 coating almost disappears, and the decrease in diffraction peak intensity is accompanied by the broadening of the peak, indicating that the grain size of the coating is significantly reduced, probably because the interfaces between the nano-layers interrupt the columnar crystal growth mode of the coating. With the addition of oxygen, the (111) crystal plane of the ZrN phase in the coating becomes its preferred growth direction.

[0050] Figure 3 High-resolution transmission electron microscopy (HRTEM) image of the ZrON-2 nano-multilayer coating. Figure 3 (a) Along the crystal growth direction, an obvious alternating structure of thick and thin layers can be observed, showing a typical nano-multilayer morphology. The selected area electron diffraction (SAED) result of area A confirms that the thick layer is mainly the ZrN phase. Figure 3 (b) In Figure 3 Area B in (a) is magnified, and the crystal plane orientation relationship between the ZrN layer and the ZrO2 layer is further marked and confirmed, verifying the multi-layer nano-structure constructed by the alternating deposition of ZrN / ZrO2 in the coating.

[0051] Figure 4 Electrochemical impedance spectra of ZrN, ZrON-1, and ZrON-2 coatings in SBF solution are shown. As can be seen from the Nyquist plot, all three coatings show typical capacitive characteristics, among which the ZrON-2 coating has the largest capacitance arc diameter and the ZrN coating has the smallest. The Bode plot shows that the ZrON-2 coating has a higher impedance modulus (|Z|) and a phase angle closer to 90°, indicating that a denser and more effective passivation film is formed on its surface. Combining the equivalent circuit fitting results, the charge transfer resistances (Rct) of the three coatings are: ZrN: 7.082×10 5 Ω·cm 2, ZrON-1: 8.023×10 5 Ω·cm 2 , ZrON-2: 2.362×10 6 Ω·cm 2 . The R of the ZrON-2 coating ct value is 3.3 times that of the ZrN coating, indicating that it has a stronger ability to block charge transfer and better corrosion resistance in the corrosive medium. This performance improvement can be attributed to the dense nano-multilayer structure of the ZrON-2 coating and the stable passive film formed by the higher proportion of ZrO2 phase.

[0052] Figure 5 are the potentiodynamic polarization curves of ZrN, ZrON-1 and ZrON-2 coatings in SBF solution. As can be seen from the figure, the current density in the anodic polarization curve of the ZrN coating rises rapidly, lacking an obvious passivation plateau, indicating that it is prone to anodic dissolution in the corrosive medium and has poor corrosion resistance. While the ZrON-1 and ZrON-2 coatings with an oxygen-doped nano-multilayer structure show good passivation behavior, the current density in the anodic region is significantly reduced, and a stable passivation section appears. The self-corrosion current density (i corr ) of the three coatings are respectively: ZrN: 9.189×10 -8 A / cm 2 , ZrON-1: 8.200×10 -8 A / cm 2 , ZrON-2: 2.327×10 -8 A / cm 2 . Among them, the ZrON-2 coating has the lowest corrosion current density, only about 25% of the ZrN coating, and also shows a wider and more stable passivation zone in the polarization curve, indicating that it has higher chemical stability and excellent corrosion resistance. The performance advantage of the ZrON-2 coating is mainly attributed to the stable passive film formed by its dense ZrO2 / ZrN nano-multilayer structure, which can effectively inhibit the penetration of the corrosive medium and the electron transfer process, thus significantly delaying the corrosion process.

[0053] Figure 6 shows the curves of the open circuit potential (OCP) and the coefficient of friction (COF) varying with time of the three coatings with different oxygen contents in the corrosion wear experiment. Figure 7 Further summarizes the comparison results of their average coefficient of friction and wear rate. In Figure 6In (a), all samples showed stable OCP values at the initial stage of immersion, indicating the formation of a preliminary passive film on the surface. With the start of friction, the ZrN and ZrON-1 coatings showed obvious "rapid OCP drop - rapid recovery" characteristics, forming a typical "V"-shaped fluctuation, indicating that their passive films were easily damaged but had a certain ability to repassivate. In contrast, the OCP change of the ZrON-2 coating was more stable during the entire friction stage, indicating that the surface friction film had higher stability and could continuously protect the coating from corrosion media erosion. Figure 6 The friction coefficient curves in (b) further verified the anti-wear behavior of the coatings. The ZrON-2 coating showed the lowest and most stable COF (average value of 0.75), followed by the ZrON-1 coating (0.78), while the ZrN coating had severe friction fluctuations and the highest COF (0.85), indicating the worst wear resistance and lubricity.

[0054] Figure 7 The average friction coefficients and wear rates of the three coatings were quantitatively compared. The results showed that the ZrON-2 coating had the best comprehensive performance during the corrosion wear process, with the lowest wear rate (6.61×10 -6 mm 3 (Nm) -1 ), far lower than that of the ZrON-1 coating (1.22×10 -5 mm 3 (Nm) -1 ) and the ZrN coating (9.10×10 -6 mm 3 (Nm) -1 ). This trend was attributed to the dense nanomultilayer structure and stable self-repairing friction film formed under high oxygen flux conditions, which could effectively slow down mechanical wear and corrosion media penetration.

[0055] Figure 8 (a) and (a’) showed that there were a large number of plough-shaped deep grooves and fragmentation and spalling areas in the wear marks of the ZrN coating, showing typical severe abrasive wear. The enlarged view showed that a large number of blocky particles were formed after the coating fragmentation and remained in the wear marks, causing "third-body wear". This was because there were abundant columnar grain boundary defects in its single-layer structure and the coating had poor densification, making it difficult to resist the synergistic effect of corrosion and mechanical wear. Figure 8 Although the wear marks of the ZrON-1 coating shown in (b) and (b’) were relatively flat as a whole, local cracking and large-area peeling areas could be seen on the surface, indicating that it initially had the advantage of structural densification. However, due to the low oxygen content, a continuous and dense friction film could not be effectively formed, resulting in crack propagation and surface layer peeling under the coupled action of local corrosion and mechanical stress, and the surface roughness of the wear marks was still relatively high. Figure 8(c) and (c’) show that the worn surface of the ZrON-2 coating is the smoothest and most compact, with the fewest surface defects, and no obvious plowing or coating spalling is observed. The enlarged view reveals that the surface is covered with a uniform and dense high-oxygen tribo-oxidation film. EDS analysis shows that its oxygen content is approximately 70%. This tribo-oxidation film formed in-situ during the friction process effectively acts as a lubricating layer, relieving the concentration of mechanical loads and inhibiting the penetration of corrosive media. Therefore, the ZrON-2 coating exhibits the lowest wear rate and the most stable OCP and COF curves in the wear-corrosion experiment (see Figure 6 and Figure 7 ).

[0056] Figure 9 shows the cross-sectional structural change characteristics of Zr-based coatings with different oxygen contents under corrosive wear. It can be seen that the structures of the ZrON-1 and ZrON-2 coatings are intact, and the Zr bonding layer at the bottom tightly binds the substrate and the ZrO2 / ZrN layer. A tribo-oxidation film formed in-situ can be found above the ZrO2 / ZrN layer. Due to the protection of the friction film, the volume loss of the ZrO2 / ZrN nanomultilayer coating during the wear process is in a controllable state. The ZrN coating subjected to friction experiments under the same conditions has a higher wear rate. From the cross-sectional morphology, it can be seen that severe coating spalling has occurred in the ZrN coating, and only the Zr bonding layer at the bottom is combined with the substrate in some areas within the worn groove, and the coating as a whole has failed. The formation of the surface tribo-oxidation film of the ZrO2 / ZrN nanomultilayer coating depends on the ultra-thin ZrO2 nanolayer in the coating. During the friction process, the coating undergoes plastic deformation and generates wear debris under the mechanical sliding of the counter ball. ZrO2 in the wear debris transforms from a crystalline state to an amorphous state under the action of friction. During the morphological transformation process, the amorphous ZrO2 phase and the crystalline ZrN phase gradually form a tribo-oxidation film with an amorphous-wrapped nanocrystalline structure. The amorphous-wrapped nanocrystalline structure reduces the defects in the friction film and provides additional bonding force, having stronger resistance to the removal of the friction film by the counter ball during the friction process. Therefore, a thicker friction film can be formed compared to conventional coatings. The thick friction film formed on the surface of the ZrO2 / ZrN nanomultilayer coating can provide long-term protection until the end of the corrosive wear process.

[0057] In the ZrO2 / ZrN nanomultilayer coating, first, the doping of O element interrupts the columnar growth of the ZrN coating, the coating grains are refined, the defects are reduced, and the structure becomes dense; the doping of O element improves the chemical activity of the ZrO2 / ZrN nanomultilayer coating, the self-corrosion potential of the coating is reduced, and a dense passivation film can also be formed; secondly, the highly mismatched semi-coherent interface between the ZrO2 nanolayer and the ZrN nanolayer can effectively affect the columnar crystal growth, reduce the "corrosion channels", delay the diffusion of the corrosive medium in the coating, and thus improve the corrosion resistance of the ZrO2 / ZrN nanomultilayer coating; finally, the O element-doped ZrO2 nanolayer can fix the wear debris during the wear-corrosion process, and the thick surface friction film formed provides corrosion protection and lubrication effects. It greatly increases the service life of the titanium alloy and has very important practical significance for biomedical devices.

[0058] The above are only the preferred embodiments of the present invention, which are illustrative rather than restrictive to the present invention. Those skilled in the art understand that many changes, modifications, and even equivalents can be made within the spirit and scope defined by the claims of the present invention, but all of them will fall within the protection scope of the present invention.

Claims

1. A method for improving the corrosion resistance and corrosion-resistant wear performance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, It includes the following steps: S1. Ultrasonically clean the titanium alloy sample and dry it. S2. Place the titanium alloy sample processed in step S1 on the substrate turntable. After heating and evacuating to vacuum, introduce argon gas, turn on the Ti target, perform ion bombardment on the substrate surface, ion-etch and clean the substrate surface, and simultaneously activate the substrate. S3. After the ion etching in step S2 ends, keep the deposition temperature and the pressure in the furnace chamber unchanged, turn on the Zr target, and deposit a metal Zr layer. S4. After the Zr metal layer deposition in step S3 is completed, keep the deposition temperature unchanged, close the argon gas, introduce oxygen gas, and deposit a ZrO2 thin film. S5. After the ZrO2 thin film deposition in step S4 ends, keep the deposition temperature unchanged, close the oxygen gas, introduce nitrogen gas, and deposit a ZrN thin film. S6. Repeat steps S5 - S6 to alternately deposit ZrO2 layers and ZrN layers to obtain a titanium alloy with a ZrO2 / ZrN nano-multilayer coating deposited on its surface.

2. A method for improving the corrosion resistance and corrosion and wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, In step S2, the argon gas flow rate is 250 - 550 sccm, the substrate negative bias voltage is -150 V, and the ion etching time is 50 min.

3. A method for improving the corrosion resistance and corrosion and wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, In step S3, the substrate bias voltage is -60 - -80 V, the target current of the metal Zr target is 110 - 140 A, and the deposition time is 5 - 10 min.

4. A method for improving the corrosion resistance and corrosion-resistant wear performance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, In step S4, the pressure after introducing nitrogen gas is 1 - 2 Pa, the nitrogen gas flow rate is 100 - 300 sccm, and the deposition time is 2 - 4 min.

5. A method for improving the corrosion resistance and corrosion and wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, In step S5, the pressure after introducing oxygen gas is 3 - 5 Pa, the O flow rate is 500 - 800 sccm, and the deposition time is 2 - 5 min.

6. A method for improving the corrosion resistance and corrosion-resistant wear performance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, In step S6, the pressure after introducing nitrogen gas is 2 - 4 Pa, the N2 flow rate is 400 - 800 sccm, and the deposition time is 3 - 6 min.

7. A method for improving the corrosion resistance and corrosion and wear resistance of a titanium alloy surface by in-situ forming a self-healing thick film, characterized in that, In step S6, the ZrO2 / ZrN nano-multilayer coating includes multiple ZrO2 / ZrN coating units. The ZrO2 / ZrN coating unit includes an oxygen-containing ZrO2 layer and a nitrogen-containing ZrN layer. The thickness of the ZrO2 layer is 10 nm, the thickness of the ZrN layer is 20 nm, and the thickness of the ZrO2 / ZrN coating unit is 30 nm.

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