A titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method

Abstract

The present invention provides a low-temperature permeation and plating integrated composite hardening insulation treatment method for titanium alloy surface, comprising the following steps: step 1, pickling and etching; step 2, placing the pickled and dried titanium alloy sample into a permeation and plating integrated composite treatment device, wherein the permeation and plating integrated composite treatment device is equipped with a high-energy pulse plasma power supply and a HIPIMS power supply; step 3, kilovolt bias sputtering, pre-injection of nitrogen ions or oxygen ions; step 4, high-power pulse ion nitriding or oxygenation treatment; step 5, sputtering to generate a TiWN-based primer layer: turning on a titanium target and a tungsten target, the titanium target and the tungsten target are controlled by a DC cathode, and a gradient multi-element TiWN coating is prepared by adjusting the ratio of Ti and W; step 6, sputtering to generate a TiWCN base surface layer. The nitriding or oxygenation strengthening operation of the titanium alloy sample substrate and the deposition of a high-hardness insulating coating are completed in the permeation and plating integrated composite treatment device, which can achieve permeation and plating integrated and efficient treatment. Moreover, the nitriding or oxygenation treatment is carried out at a relatively low temperature, and almost no deformation of the titanium alloy substrate occurs.

Description

Technical Field

[0001] The invention relates to the technical field of metal surface coatings, and in particular to a low-temperature permeation and plating integrated composite hardening insulation treatment method for titanium alloy surfaces. Background Art

[0002] Titanium alloys are widely used in the fields of shipbuilding, ocean, aerospace, process industry equipment, etc. due to their excellent properties such as low density, high specific strength, and excellent corrosion resistance. However, titanium alloys have low hardness and poor resistance to friction and wear, which leads to problems such as wear, adhesion and biting. For example, the wear caused by the contact between the valve stem and the valve disc of marine titanium alloy valves has greatly affected the reliable operation of ship components. In addition, the formation of a natural oxide layer on the surface of titanium alloys causes titanium alloys to have a higher electric potential. In the marine environment, especially when dissimilar metal related components are assembled and contacted, the large potential difference causes galvanic corrosion, which further aggravates the wear and is a prominent problem that plagues the long-term safe operation of ships.

[0003] To address the wear and galvanic corrosion problems of titanium alloys caused by contact with dissimilar metal parts, existing technologies mainly improve the problem by hardening and insulating the metal surface to reduce the potential difference. The main technical approaches include micro-arc oxidation, anodizing, plasma spraying, ion nitriding, physical vapor deposition, etc. Although these surface treatment technologies can increase the surface hardness of titanium alloys and improve wear resistance to a certain extent, the high temperature of the traditional nitriding process causes deformation and increased roughness of the workpiece. The subsequent processing leads to low processing efficiency and cannot be effectively connected with the coating process, and the improvement of the hardness of the titanium alloy is also limited. In addition, the corrosion resistance of the nitrided layer is poor and cannot meet the service requirements in marine environments. Micro-arc oxidation and anodizing coatings have high porosity and low hardness. Physical vapor deposition hard coatings can achieve a significant increase in hardness, but the hardness match between the soft titanium alloy substrate and the high-hardness coating is poor, and the hard layer is easily damaged and falls off under high loads.

[0004] The invention patent application with application number CN2021105831529 proposes a surface nitriding treatment method for titanium alloy parts. The surface to be nitrided is obtained by rough machining the raw material of the preheated titanium alloy parts. The rough machining also includes machining the surface to be nitrided to the final size of the finished part, and then performing surface nitriding treatment to reduce the impact of high-temperature deformation on the final size of the workpiece. After nitriding, the surface hardness of the workpiece can reach 1000HV, which can effectively improve the wear resistance of the titanium alloy workpiece. However, on the one hand, this technology has limited effect on improving the hardness of titanium alloys. On the other hand, it reduces the impact of deformation on the size of the workpiece by machining methods, but does not actually reduce the nitriding temperature to avoid deformation.

[0005] Invention patent application number CN2019109426430 proposes a method for nitriding the surface of TC4 titanium alloy using a hot-wire-enhanced glow discharge low-temperature plasma process. This method can achieve nitriding of the titanium alloy surface at around 500°C, forming a uniform nitrogen-containing titanium alloy solid solution phase, significantly improving the mechanical properties of the titanium alloy. However, this method only describes the nitriding process and does not involve the preparation of a composite film layer. In particular, the method involves the integrated deposition of a gradient composite film layer on the substrate surface during nitriding to improve the corrosion and wear resistance of the substrate. Summary of the Invention

[0006] In view of this, the present invention aims to propose a low-temperature nitriding and plating integrated composite hardening insulation treatment method for titanium alloy surface to solve the deformation problem caused by the high temperature during nitriding or oxygenation treatment, and overcome the cumbersome process caused by the traditional multi-equipment and multi-process path of first nitriding and then surface finishing and then coating.

[0007] To achieve the above object, the technical solution of the present invention is achieved as follows:

[0008] A method for treating a titanium alloy surface with low-temperature permeation and plating integrated composite hardening insulation treatment comprises the following steps:

[0009] Step 1: pickling and etching;

[0010] Step 2: placing the pickled and dried titanium alloy sample into an integrated infiltration and plating composite treatment device equipped with a high-energy pulsed plasma power supply and a HIPIMS power supply;

[0011] Step 3: Sputtering with a kilovolt bias to pre-implant nitrogen or oxygen ions;

[0012] Step 4: high power pulse ion nitriding or oxygen permeation treatment;

[0013] Step 5: Sputtering to form a TiWN-based bottom layer: Turn on the titanium target and the tungsten target, which are controlled by a DC cathode, and prepare a gradient multi-element TiWN coating by adjusting the ratio of Ti and W;

[0014] Step six: sputtering to form a TiWCN basal layer.

[0015] Furthermore, in step 3, the high-energy pulse plasma power supply is turned on, the bias peak is regulated at 3000-6000V for sputtering, the gas pressure is set to 0.3-0.5Pa, and the sputtering time is 30-45min; after improving the reaction activity of the titanium alloy sample matrix, 0.1-0.3m 3 / h of nitrogen or oxygen, and adjust the temperature to 350-400°C for 1-1.5h to pre-implant N or O ions.

[0016] Furthermore, in step 4, the HIPIMS power supply is turned on, the working gas is adjusted to nitrogen or oxygen, and hydrogen, the bias voltage is 8-15kV, the vacuum degree is below 10Pa, and the nitrogen or oxygen flow rate is 0.2-0.5m 3 / h, hydrogen flow rate is 0.1-0.2m 3 / h, temperature is 350-480℃, treatment is 5-8h, forming nitriding layer or oxygen permeating layer.

[0017] Furthermore, the thickness of the nitriding layer or the oxygen permeating layer is 1-2 μm.

[0018] Furthermore, the step five includes two stages. In the first stage, the working gases are argon and nitrogen, and the sputtering parameters of the titanium target and the tungsten target are controlled at the same time so that the ratio of the titanium target and the tungsten target components is 1:3. The HIPIMS power supply pulse high voltage is 20-25kV, the pulse width is 20-30μs, the pulse frequency is 100-150Hz, the working gas pressure of argon is 0.2-0.4Pa, and the argon partial pressure is 0.10-0.20Pa.

[0019] Furthermore, in step five, the second stage is to again adjust the sputtering parameters of the titanium target and the tungsten target during the co-sputtering process, so that the ratio of the titanium target and the tungsten target components is gradually reduced to 1:1, and finally a 0.3-0.5 μm gradient transition TiWN-based base layer is generated by reactive sputtering.

[0020] Furthermore, in step six, the titanium target, tungsten carbide target and graphite target are turned on at the same time, the working gases are argon and nitrogen, the substrate is applied with a pulse bias of 15-20 kV, a pulse width of 20-40 μs, a pulse frequency of 100-200 Hz, a working gas pressure of 0.4-0.8 Pa, an argon flow rate of 30-50 sccm, and a nitrogen flow rate of 5-10 sccm, and the ratio of Ti and WC components is adjusted from 1:1 to 1:3-1:4, and the deposition time is 3-4.5 h.

[0021] Furthermore, in step six, a TiWCN basal layer with a thickness of 4-8 μm is sputtered on the surface of the titanium alloy sample.

[0022] Compared with the existing technology, the titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method described in the present invention has the following advantages:

[0023] (1) The titanium alloy sample substrate is nitrided or oxygenated to strengthen and the high-hardness insulating coating is deposited in an integrated plating and nitriding composite processing device, which can realize integrated plating and nitriding composite and efficient processing, avoid the need for surface finishing before coating, and save time and process.

[0024] (2) Nitriding or oxygenation treatment is carried out at a relatively low temperature, and almost no deformation of the titanium alloy matrix occurs.

[0025] (3) Sputtering to generate a TiWN-based base layer includes two stages. On the one hand, the staged sputtering can make the deposited base layer have both high bonding strength and a gradient increase in hardness, and have a better gradient transition with the subsequent surface layer hardness, thereby increasing the coating's load-bearing capacity and shear resistance. On the other hand, without changing the target material, the coating composition and structure can be better changed in stages, and the composition and structure can be naturally transitioned. It can also serve as a growth template to induce the growth of TiWCN nano-columnar crystals in the surface layer, thereby improving the surface layer density and insulation performance.

[0026] (3) The composite treated specimens of the present invention have high hardness, reaching 22 GPa, and exhibit a good hardness gradient transition effect, significantly improving wear resistance. The bonding strength between the nitrided or oxygenated layer and the coating reaches 60 N, making it difficult to fall off the substrate. The surface resistance of the specimens is greater than 200 megohms, and they have good corrosion resistance in marine environments, which can increase the service life of titanium alloy components for ships in marine environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The accompanying drawings, which constitute part of the present invention, are provided to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are provided to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0028] Figure 1 Schematic diagram of the integrated composite treatment of kilovolt-level pulsed plasma permeation and plating according to the present invention;

[0029] Figure 2 Schematic diagram of the structure of the gradient coating by integrated composite treatment of permeation and plating according to the present invention;

[0030] Figure 3 This is an appearance diagram of the TA2 titanium alloy after being treated in Example 1 of the present invention;

[0031] Figure 4 This is a diagram showing the cross-sectional morphology and thickness of each layer of the film layer subjected to the integrated permeation and plating composite treatment in Example 1 of the present invention;

[0032] Figure 5 This is a microscopic morphology characterization diagram of the surface of the TA2 titanium alloy after being treated in Example 1 of the present invention;

[0033] Figure 6 This is the appearance of the Ti80 titanium alloy after being treated in accordance with Invention Example 2;

[0034] Figure 7 This is a diagram showing the cross-sectional morphology and thickness of each layer of the film layer subjected to the integrated composite treatment of permeation and plating according to Example 2 of the present invention;

[0035] Figure 8 This is a microscopic morphology characterization diagram of the Ti80 titanium alloy surface after treatment in Example 2 of the present invention. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with specific embodiments. It should be noted that the data in the following experimental examples are obtained by the inventor through a large number of experiments. Due to space limitations, only a portion thereof is shown in the specification, and those skilled in the art can understand and implement the present invention under these data. These embodiments are merely intended to illustrate the present invention and are not intended to limit the scope of the present invention. It should also be understood that, after having read the contents of the present invention, those skilled in the art may make various changes or modifications to the present invention, and these changes or modifications also fall within the scope protected by this application.

[0037] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0038] The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments.

[0039] The present invention provides a titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method, comprising the following steps:

[0040] Step 1: pickling and etching;

[0041] Specifically, in step 1, the titanium alloy sample is soaked in hydrofluoric acid, then wiped with sandpaper to interrupt the continuity of the natural oxide layer on the surface, and then cleaned with acetone and alcohol, and dried with compressed air.

[0042] Step 2: placing the pickled and dried titanium alloy sample into an integrated infiltration and plating composite treatment device equipped with a high-energy pulsed plasma power supply and a HIPIMS power supply;

[0043] Specifically, in step 2, a high-energy pulse plasma power supply is used to control the bias peak at the kilovolt level to perform ion energy regulation, replacing the temperature regulation of traditional titanium alloy nitriding, and achieving high-energy nitrogen or oxygen injection at low temperatures below 480°C. The high-power pulsed magnetron sputtering (HIPIMS) power supply configured at the same time is conducive to the deposition of an integrated high-density nano-columnar crystal coating by regulating parameters such as pulse voltage, air pressure, and pulse width. The present invention integrates the nitriding or oxygenation of the titanium alloy substrate and the deposition of the coating, which not only avoids the formation of an oxide layer caused by sending it to the next process after nitriding or oxygenation, and the waste of resources caused by the extra time and manpower and material resources for cooling and polishing, but also the sample after the composite integrated treatment has a higher hardness.

[0044] Step 3: Sputtering with a kilovolt bias to pre-implant nitrogen or oxygen ions;

[0045] As a preferred example of the present invention, in step 3, the high-energy pulse plasma power supply is turned on, the bias peak is regulated at 3000-6000V for sputtering, the gas pressure is set to 0.3-0.5Pa, and the sputtering time is 30-45min; after improving the reaction activity of the titanium alloy sample matrix, 0.1-0.3m 3 / h of nitrogen or oxygen, and adjust the temperature to 350-400°C for 1-1.5h to pre-implant N or O ions.

[0046] Controlling the pulse bias peak at 3000-6000V can not only bombard and remove the residual oxide film layer on the surface of the titanium alloy, but also achieve the effect of gas ion implantation, avoiding temperature accumulation caused by excessive heating, so as to realize low-temperature pre-nitriding or low-temperature pre-oxygenation of titanium alloy samples.

[0047] Step 4: high power pulse ion nitriding or oxygen permeation treatment;

[0048] As a preferred example of the present invention, in step 4, the HIPIMS power supply is turned on, the working gas is adjusted to nitrogen or oxygen, and hydrogen, the bias voltage is 8-15kV, the vacuum degree is below 10Pa, and the nitrogen or oxygen flow rate is 0.2-0.5m 3 / h, hydrogen flow rate is 0.1-0.2m 3 / h, temperature is 350-480℃, treatment is 5-8h, forming nitriding layer or oxygen permeating layer.

[0049] In step 4, a 1-2μm nitriding or oxygenating layer is formed, which can strengthen the matrix and increase the hardness. Low-temperature nitriding or oxygenating treatment at 350-480°C can prevent deformation of the carbon alloy matrix and achieve a good hardness transition between the nitriding layer and the plating layer.

[0050] Step 5: Sputtering to form a TiWN-based bottom layer: Turn on the titanium target and the tungsten target, which are controlled by a DC cathode, and prepare a gradient multi-element TiWN coating by adjusting the ratio of Ti and W;

[0051] As a preferred example of the present invention, step five includes two stages. In the first stage, the working gases are argon and nitrogen, and the sputtering parameters of the titanium target and the tungsten target are controlled at the same time so that the ratio of the titanium target and the tungsten target components is 1:3. The HIPIMS power supply pulse high voltage is 20-25kV, the pulse width is 20-30μs, the pulse frequency is 100-150Hz, the working gas pressure is 0.2-0.4Pa, and the argon partial pressure is 0.10-0.20Pa. In the second stage, the sputtering parameters of the titanium target and the tungsten target during the co-sputtering process are again regulated so that the ratio of the titanium target and the tungsten target components is gradually reduced to 1:1, and finally a gradient transition TiWN-based base layer of 0.3-0.5μm is generated by reactive sputtering. The first stage is used to enhance the bonding strength between the base layer and the nitrided substrate or the base layer and the oxygenated matrix in the initial stage of sputtering deposition. The TiWN-based base layer generated in the second stage can improve the bonding strength with the nitrided or oxygenated substrate, while achieving a gradient transition in hardness.

[0052] Step five includes two stages. On the one hand, sputtering in stages can make the deposited base layer have both high bonding strength and a gradient increase in hardness, and have a better gradient transition with the subsequent surface layer hardness, thereby increasing the coating's load-bearing capacity and shear resistance. On the other hand, without changing the target material, the coating composition and structure can be better changed in stages, with a natural transition of composition and structure, and the surface layer can be used as a growth template to induce the growth of TiWCN nanocolumnar crystals, thereby improving the surface layer density and insulation performance.

[0053] Step six: sputtering to form a TiWCN basal layer.

[0054] As a preferred example of the present invention, in step six, the titanium target, tungsten carbide target and graphite target are turned on at the same time, the working gases are argon and nitrogen, the substrate is applied with a pulse bias of 15-20 kV, a pulse width of 20-40 μs, a pulse frequency of 100-200 Hz, a working gas pressure of 0.4-0.8 Pa, an argon flow rate of 30-50 sccm, and a nitrogen flow rate of 5-10 sccm. The ratio of Ti and WC components is adjusted from 1:1 to 1:3-1:4, and the deposition time is 3-4.5 h. A 4-8 μm thick TiWCN base layer is sputtered on the surface of the titanium alloy sample.

[0055] The TiWCN base layer has high hardness and good insulation properties. In addition to improving the hardness to achieve improved wear resistance, it can also achieve insulation between dissimilar metals and prevent galvanic corrosion by adjusting the WC component to prepare coatings with different WC contents.

[0056] Figure 1 This is a schematic diagram of the integrated composite treatment of kilovolt pulse plasma plating according to the present invention. Figure 2As shown, the sample treated by the titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method of the present invention comprises, from top to bottom: TiWCN base surface layer, TiWN base primer layer, nitriding layer or oxygen permeating layer, and titanium alloy body bottom layer.

[0057] The present invention completes the nitriding or oxygenation strengthening of the titanium alloy sample matrix and the deposition of the high-hardness insulating coating in an integrated nitriding and plating composite processing device, which can achieve integrated nitriding and plating and efficient processing. In the traditional process, nitriding and oxygenation and coating are completed in different equipment, and surface finishing is required before coating, and the improvement of the surface hardness of the titanium alloy is limited. The sample after the composite treatment of the present invention has high hardness, which can reach 22GPa. At the same time, it has a good hardness gradient transition effect, which greatly improves the wear resistance. The nitriding or oxygenation treatment is carried out at a relatively low temperature, and the titanium alloy matrix is ​​almost free of deformation. The bonding strength between the nitriding layer or oxygenation layer and the coating reaches 60N, and it is not easy to fall off from the substrate. The sample after the treatment of the present invention has a surface resistance greater than 200 megohms and has good corrosion resistance in the marine environment, which can increase the service life of titanium alloy components for ships in the marine environment.

[0058] Example 1

[0059] The surface of TA2 titanium alloy was soaked in hydrofluoric acid and sanded to remove the natural oxide layer, increasing the roughness from the original 0.5μm to 1.6μm. It was then ultrasonically cleaned with acetone, alcohol, and deionized water for 15 minutes.

[0060] The cleaned TA2 titanium alloy sample was placed in the integrated composite treatment equipment for diffusion and plating, and the high-energy pulse plasma power supply was turned on. The bias peak was regulated at 4000V, the ion energy was regulated for sputtering, the gas pressure was controlled at 0.4Pa, and the sputtering time was 40min. After improving the reaction activity of the titanium alloy matrix, 0.1m 3 / h of nitrogen, and adjust the temperature to 350-400°C for 1 hour to pre-inject N ions.

[0061] Turn on the HIPIMS power supply, adjust the working gas to nitrogen and hydrogen, bias voltage 8-12kV, vacuum degree below 10Pa, and nitrogen flow rate 0.3m 3 / h, hydrogen flow rate is 0.1m 3 / h, with a nitrogen and hydrogen partial pressure of 1:8, a high-power pulse nitriding temperature of 480°C, and a treatment time of 6 hours, a 2μm nitriding layer is formed. The nitriding layer can strengthen the titanium alloy substrate and increase the hardness.

[0062] The titanium and tungsten targets are turned on and controlled by a DC cathode, and the ratio of Ti and W is adjusted in stages. In the first stage, the working gases are argon and nitrogen, the HIPIMS power supply pulse high voltage is 20kV, the pulse width is 20μs, the pulse frequency is 150Hz, the working gas pressure is 0.3Pa for argon, the nitrogen partial pressure is 0.15Pa, and the Ti to W component ratio is 1:3. In the second stage, the Ti to W component ratio is then gradually reduced to 1:1, and finally a 0.3μm gradient transition TiWN-based base layer is generated through reactive sputtering. The TiWN-based base layer not only improves the bonding strength with the nitrided substrate, but also achieves a gradient transition in hardness.

[0063] Titanium target, tungsten carbide target and graphite target were sputtered simultaneously, and a pulse bias of 15 kV, a pulse width of 20-40 μs, a pulse frequency of 200 Hz, a working gas pressure of 0.8 Pa, an argon flow rate of 30 sccm, and a nitrogen flow rate of 5 sccm were applied to the substrate. The ratio of Ti and WC components was adjusted from 1:1 to 1:4, and the deposition time was 4 h. A 6-8 μm thick TiWCN basal layer was sputtered on the surface of the titanium alloy sample.

[0064] Example 2

[0065] The Ti80 titanium alloy surface was immersed in hydrofluoric acid and sanded to remove the natural oxide layer, increasing the roughness from the original 0.5 μm to 1.2 μm. It was then ultrasonically cleaned with acetone, alcohol, and deionized water for 15 minutes.

[0066] The cleaned Ti80 titanium alloy sample was placed in the integrated composite treatment equipment for diffusion and plating, and the high-energy pulse plasma power supply was turned on. The bias peak was regulated at 6000V, the ion energy was regulated for sputtering, the gas pressure was controlled at 0.3Pa, and the sputtering time was 30min. After improving the reaction activity of the titanium alloy matrix, 0.3m 3 / h of nitrogen, and adjust the temperature to 350-400°C for 1.5h to perform pre-injection of N ions.

[0067] Turn on the HIPIMS power supply, adjust the working gas to nitrogen and hydrogen, bias voltage 10-15kV, vacuum degree below 0.1Pa, and nitrogen flow rate 0.5m 3 / h, hydrogen flow rate is 0.2m 3 / h, with a nitrogen and hydrogen partial pressure of 1:6, a high-power pulse nitriding temperature of 450°C, and a treatment time of 5 hours, a 1μm nitriding layer is formed. The nitriding layer can strengthen the titanium alloy substrate and increase the hardness.

[0068] The titanium target and tungsten target are turned on and controlled by a DC cathode, and the ratio of Ti and W is adjusted in stages. In the first stage, the working gases are argon and nitrogen, the HIPIMS power supply pulse high voltage is 25kV, the pulse width is 30μs, the pulse frequency is 100Hz, the working gas pressure is 0.35Pa for argon, the nitrogen partial pressure is 0.20Pa, and the Ti to W component ratio is 1:3. In the second stage, the Ti to W component ratio is then gradually reduced to 1:1, and finally a 0.5μm gradient transition TiWN-based base layer is generated through reactive sputtering. The TiWN-based base layer not only improves the bonding strength with the nitrided substrate, but also achieves a gradient transition in hardness.

[0069] Titanium target, tungsten carbide target and graphite target were sputtered simultaneously, and a pulse bias of 20 kV, a pulse width of 20-40 μs, a pulse frequency of 200 Hz, a working gas pressure of 0.4 Pa, an argon flow rate of 50 sccm, and a nitrogen flow rate of 10 sccm were applied to the substrate. The ratio of Ti and WC components was gradually increased from 1:1 to 1:3, and the deposition time was 4.5 h. A 4-6 μm thick TiWCN basal layer was sputtered on the surface of the titanium alloy sample.

[0070] Figure 3-5 They are respectively the appearance picture of TA2 titanium alloy after being treated by the method of Example 1, the cross-sectional morphology of the film layer treated by the integrated diffusion and plating composite treatment and the thickness characterization picture of each layer, and the surface micromorphology characterization picture. Figure 6-8 The following images show the appearance of the Ti80 titanium alloy treated using the method of Example 2, the cross-sectional morphology and thickness of the film layer after the integrated permeation and plating composite treatment, and the surface micromorphology. It can be seen that the treatment method of the present invention can produce a titanium alloy with a good appearance, smoothness, and no deformation. The TiWCN basal layer can be well deposited on the TiWN base layer, thereby improving hardness and dielectric strength.

[0071] The hardness and bonding strength of the samples of Example 1 and Example 2 are shown in Table 1. The nanohardness tester was a nanoindentation tester, and the bonding strength tester was a nanoscratch tester. Five groups of samples were tested for each example.

[0072] Table 1

[0073]

[0074] As can be seen from Table 1, the samples of Example 1 and Example 2 obtained by the treatment method of the present invention have a nanohardness of 20.24-21.56 GPa and a bonding force of 59.4-60 N, which can greatly improve the hardness and friction and wear resistance. The deposited TiWCN base layer has a strong bonding force, which can prevent galvanic corrosion and severe wear that occur when the titanium alloy serving in the marine environment comes into contact with dissimilar metal parts.

[0075] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for treating titanium alloy surface with low-temperature permeation and plating integrated composite hardening insulation treatment, characterized in that: The steps include: Step 1: pickling and etching; Step 2: placing the pickled and dried titanium alloy sample into an integrated infiltration and plating composite treatment device equipped with a high-energy pulsed plasma power supply and a HIPIMS power supply; Step 3: Sputtering with kilovolt bias, pre-injecting nitrogen ions or oxygen ions: Turn on the high-energy pulse plasma power supply, adjust the bias peak value to 3000-6000V for sputtering, set the gas pressure to 0.3-0.5Pa, and the sputtering time to 30-45min; after increasing the reaction activity of the titanium alloy sample matrix, introduce 0.1-0.3m 3 / h of nitrogen or oxygen, and adjust the temperature to 350-400 ° C, the treatment time is 1-1.5 hours, and pre-implantation of N or O ions is performed; Step 4: High-power pulsed ion nitriding or oxygen permeation treatment: Turn on the HIPIMS power supply, adjust the working gas to nitrogen or oxygen, and hydrogen, bias 8-15kV, vacuum degree below 10Pa, nitrogen or oxygen flow rate 0.2-0.5m 3 / h, hydrogen flow rate is 0.1-0.2m 3 / h, temperature 350-480℃, treatment for 5-8h to form nitriding layer or oxygen permeating layer; Step 5: Sputtering to generate a TiWN-based bottom layer: turning on the titanium target and the tungsten target, which are controlled by a DC cathode, and adjusting the ratio of Ti and W to prepare a gradient multi-element TiWN coating; comprising two stages, the first stage: the working gas is argon and nitrogen, and the sputtering parameters of the titanium target and the tungsten target are controlled at the same time so that the ratio of the titanium target and the tungsten target components is 1:3, the HIPIMS power supply pulse high voltage is 20-25kV, the pulse width is 20-30μs, the pulse frequency is 100-150Hz, the working gas pressure is 0.2-0.4Pa, and the argon partial pressure is 0.10-0.20Pa; the second stage is to again adjust the sputtering parameters of the titanium target and the tungsten target during the co-sputtering process so that the ratio of the titanium target and the tungsten target components is gradually reduced to 1:1, and finally a gradient transition TiWN-based bottom layer is generated by reactive sputtering; Step six, sputtering to generate a TiWCN base layer: the titanium target, tungsten carbide target and graphite target are turned on at the same time, the working gases are argon and nitrogen, the substrate is applied with a pulse bias of 15-20kV, a pulse width of 20-40μs, a pulse frequency of 100-200Hz, a working gas pressure of 0.4-0.8Pa, an argon flow rate of 30-50sccm, and a nitrogen flow rate of 5-10sccm. The ratio of Ti and WC components is adjusted from 1:1 to gradually increase to 1:3-1:4, and the deposition time is 3-4.5h.

2. The titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method according to claim 1, characterized in that: The thickness of the nitriding layer or the oxygen permeating layer is 1-2 μm.

3. The titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method according to claim 1, characterized in that: In step five, the thickness of the gradient transition TiWN-based primer layer is 0.3-0.5 μm.

4. The titanium alloy surface low-temperature permeation and plating integrated composite hardening insulation treatment method according to claim 1, characterized in that: In the step six, a TiWCN basal layer with a thickness of 4-8 μm is formed on the surface of the titanium alloy sample by sputtering.

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