Preparation method of a titanium-carbon nano-multilayer composite wear-resistant coating material for artificial joint surface

Abstract

The present invention belongs to the technical field of artificial joint preparation, and particularly relates to a preparation method of a titanium-carbon nano multi-layer composite wear-resistant coating material for the surface of an artificial joint. The method of the present invention includes: S01. Preparing a 3D-printed titanium alloy as a substrate material and pre-treating the substrate material; S02. Alternately preparing Ti-TiN layers with an interface fusion characteristic by using cathodic arc ion plating and anodic layer ion beam; S03. Preparing an amorphous carbon lubricating layer. The present invention proposes a composite structure idea that integrates a bonding layer on the surface of the substrate, an intermediate energy absorption layer with an interface fusion structure, and a top lubricating layer, and prepares a titanium-carbon composite protective coating material with a multi-layer interface fusion characteristic based on an alternately gradual arc ion plating method.

Description

[0001] Priority Application

[0002] This application claims the priority of the Chinese invention patent application [CN202311707996.5] "A Wear-Resistant Coating on the Surface of a Titanium Alloy Artificial Joint and Its Preparation Method" filed on December 12, 2023, and the entire text of the priority invention patent application is incorporated herein by reference. Technical Field

[0003] The present invention belongs to the technical field of artificial joint preparation, and specifically relates to a preparation method of a titanium-carbon nano-multilayer composite wear-resistant coating material for the surface of an artificial joint. Background Art

[0004] The special internal environment of the human body poses the most basic requirements for artificial joint materials, including: (1) excellent biocompatibility; (2) good biomechanical compatibility; (3) excellent bio-binding performance and stability; (4) a long service life. However, for various types of artificial joints currently in use, there are generally problems such as easy wear, loosening, dislocation, deviation, and sharp friction noise of artificial joint prostheses.

[0005] 3D printing customized joints provide a new opportunity to solve the deficiencies of traditional forming methods (difficulty in forming complex modified joints, inability to produce personalized products, etc.). The good specific strength and excellent biocompatibility of titanium alloys have made progress in the clinical application of personalized all-titanium joints. However, due to its poor shear strength, titanium alloy faces the problem of excessive wear under biological corrosion conditions when used as a joint friction interface material, seriously affecting the long-term safe use of implanted prostheses.

[0006] The patent with the publication number CN101090743A and the invention title "False Joint with an Articular Surface Layer Comprising ADLC" discloses a false joint with a surface protective coating material, and the surface of the false joint has amorphous diamond-like carbon (ADLC). This patented technology proposes to set a bonding layer between the base layer and the surface layer ADLC, including (substrate)-Ti-TiN-Ti-TiN. Those skilled in the art generally believe that the performance of the bonding layer is crucial for the performance of the overall coating. However, this patent does not disclose a clear and operable preparation method for the bonding layer, and the performance comparison effect in the patent examples is even unclear. Therefore, this patent only proposes a structural design of a prosthetic joint. The research on the design and performance comparison of the surface protective coating material is not in-depth enough, and no effective surface modification technical solution is proposed.

[0007] Currently, there are usually two ways to strengthen the friction interface of 3D-printed titanium alloy artificial joints: 1) The method of separately printing a set of friction components made of cobalt-chromium-molybdenum alloy and assembling them with the prosthesis main body. This method uses traditional implant materials such as cobalt-chromium-molybdenum to improve the biological and tribological properties of the friction interface and extend the service life of the joint. However, this method has the disadvantages of a long production design cycle and high cost for joint prostheses. More importantly, the method of block printing-assembly integrated use will also result in multiple interfaces of dissimilar metals in the prosthesis, and the existence of these interfaces causes problems such as interfacial galvanic corrosion and fretting friction during the use of the joint prosthesis, which not only cannot fully utilize the advantages of 3D printing in the design and processing of personalized joint prostheses, but may even bring other potential hazards. 2) Preparing a high-strength wear-resistant coating material on the surface of titanium alloy to improve the service life of the joint prosthesis. This method uses surface engineering technology to prepare a protective coating material with wear-resistant and high-hard characteristics on the surface of the prosthesis. Usually, the physical vapor deposition method is used for preparation, but this method generally has high requirements for the selection of the material system and the precision of the preparation process, and precise regulation of both the composition and structure of the coating is required to achieve the preparation of high-performance coatings.

[0008] In summary, it is necessary to propose new specific and feasible methods and strategies to alleviate the deficiencies of the existing technology. Summary of the Invention

[0009] The purpose of the present invention is to provide a titanium-carbon nano-multilayer composite wear-resistant coating material for the surface of artificial joints, its preparation method and application, to partially solve or alleviate the above deficiencies in the existing technology. The present invention specifically adopts the following technical solutions.

[0010] On the one hand, the present invention provides a preparation method.

[0011] A preparation method of a titanium-carbon nano-multilayer composite wear-resistant coating material includes the following steps:

[0012] S010: Prepare 3D-printed titanium alloy as the substrate material, place the substrate material on the equipment sample holder, and rotate the sample holder to the front of the anode layer linear ion beam. Introduce argon (Ar) into the anode layer linear ion beam and ionize it, and perform pretreatment (etching) on the substrate material to remove the surface oxide film;

[0013] S020: Use cathode arc ion plating and anode layer ion beam to alternately prepare a Ti-TiN layer with the characteristic of interface fusion, and set the thickness of the prepared Ti-TiN layer to be 1.5 - 3.0 μm;

[0014] S021: Set a constant current, set the argon gas flow rate to f1, and deposit on the substrate material for a time of t1 to prepare a Ti layer;

[0015] S022: Set a constant current, set the nitrogen gas flow rate to f2, deposit on the Ti layer for a time of t2 to prepare a TiN layer; then reduce the nitrogen gas input at a rate of f3 / min and introduce argon gas at a rate of f4 / min. Gradually change the two gases to make the TiN layer transition to the Ti layer, with a duration of t3;

[0016] S023: Set a constant current, set the argon gas flow rate to f1, deposit for a time of t4 to prepare a Ti layer; reduce the argon gas input at a rate of f4 / min and increase the nitrogen gas input at a rate of f3 / min. Gradually change the two gases to make the Ti layer transition to the TiN layer (until the TiN layer is prepared), with a duration of t5;

[0017] Among them, the argon gas flow rate f1 is less than the nitrogen gas flow rate f2; the gas flow rate f3 / min is greater than the gas flow rate f4 / min;

[0018] Among them, the argon gas flow rate f1 is 150 - 200 sccm; the deposition time t1 is 10 - 30 minutes; the nitrogen gas flow rate f2 is 400 - 450 sccm; the deposition time t2 is 5 - 20 minutes; the gas flow rate f3 / min is 45 - 90 sccm / minute; the time t3 is 5 - 10 minutes; the gas flow rate f4 / min is 20 - 40 sccm / minute; the time t4 is 5 - 10 minutes; the time t5 is 5 - 10 minutes;

[0019] Repeat S022 - S023 so that the last layer prepared is the Ti layer;

[0020] S030: Rotate the sample holder to the front of the anode layer ion beam, set a constant current, set the C2H2 gas flow rate to 40 - 50 sccm, and deposit for 30 - 40 minutes to prepare an amorphous carbon (DLC) lubricating layer.

[0021] Amorphous carbon materials have high hardness, high biosecurity, and excellent wear resistance, and are excellent lubricating coating materials. However, due to their high hardness, the mechanical properties of the amorphous carbon material itself and the mechanical properties of the metal matrix are too different, and spalling and splitting are likely to occur due to mechanical property mismatch. Therefore, one of the key points of the method of the present invention is to design a bonding layer material with good supportability and toughness for the top amorphous carbon lubricating layer. The bonding layer material has a moderate hardness, plays a good supporting role between the bottom metal base layer and the top amorphous carbon layer, and can also absorb instantaneous impact energy, realizing the improvement of the comprehensive performance of the entire composite material.

[0022] As a preference, the deposition time in S030 is 30 minutes.

[0023] Further, the constant current set under S020 is greater than the constant currents set under S010 and S030.

[0024] Further, when preprocessing the substrate material, a constant current is set, the argon gas flow rate is set to 40 - 50 sccm; the temperature of the equipment cavity is set to not less than 200 °C, and the cavity pressure is set to be constant at 2.0 mTorr; the deposition time is 20 - 30 minutes.

[0025] As a preference, the argon gas flow rate is set to 48 - 50 sccm; the temperature of the equipment cavity is set to 200 °C.

[0026] As a preference, the deposition time in S010 is 30 minutes.

[0027] Further, in S021, the temperature of the equipment cavity is set to not less than 200 °C, the cavity pressure is set to 40 - 50 mTorr; the argon gas flow rate f1 is set to 200 sccm; the time t1 is 10 - 20 minutes.

[0028] As a preference, the temperature of the equipment cavity is set to 200 - 230 °C; the cavity pressure is set to 45 mTorr.

[0029] Further, in S022, the temperature of the equipment cavity is set to not less than 200 °C, the cavity pressure is set to 40 - 50 mTorr; the nitrogen gas flow rate f2 is set to 450 sccm; the time t2 is 5 - 10 minutes.

[0030] As a preference, the temperature of the equipment cavity is set to 200 - 230 °C; the cavity pressure is set to 45 mTorr.

[0031] Further, in S022, the rate of reducing the nitrogen gas introduction f3 / min is set to 45 - 90 sccm / min, the rate of introducing argon gas f4 / min is set to 20 - 40 sccm / min, and the time t3 is 5 - 10 minutes.

[0032] Further, the constant current set under S020 is 70 A; the constant current set under S030 is 0.2 A.

[0033] On the other hand, the present invention provides a product obtained by the above preparation method.

[0034] The wear-resistant coating material of titanium-carbon nano-multilayer composite prepared by the above preparation method, the wear-resistant coating material of titanium-carbon nano-multilayer composite is composed of a substrate material, an intermediate energy absorption layer and a top amorphous carbon lubricating layer from bottom to top; the intermediate energy absorption layer is a Ti-TiN layer with the characteristic of interface fusion and deposited alternately. Or, a Ti-TiN layer with the characteristic of interface fusion and deposited alternately is set as the intermediate energy absorption layer in the wear-resistant coating material of titanium-carbon nano-multilayer composite.

[0035] As a preference, the thickness of the intermediate energy absorption layer is 1.6 - 3.0 μm, and the number of layers is not less than 4 layers.

[0036] As a preference, the thickness of the intermediate energy absorption layer is 1.6 - 3.0 μm, and the number of layers is not less than 5 layers.

[0037] Furthermore, a Ti layer is used as the bonding layer between the substrate material and the intermediate energy absorption layer; a Ti layer is used as the bonding layer between the top amorphous carbon lubricating layer and the intermediate energy absorption layer. That is, the intermediate energy absorption layer is a -Ti-TiN-Ti-TiN-Ti- structural form with the characteristic of interface fusion.

[0038] Furthermore, the overall thickness of the wear-resistant coating material of titanium-carbon nano-multilayer composite is 3 - 3.5 μm.

[0039] The present invention can also provide the applications of the above preparation method and the above product.

[0040] Application of the above preparation method in the preparation of artificial wear-resistant joints.

[0041] Application of the above wear-resistant coating material of titanium-carbon nano-multilayer composite in the preparation of artificial wear-resistant joints.

[0042] The present invention optionally provides a most preferred preparation scheme, and the following scheme should be understood as an example rather than a limitation.

[0043] A preparation method of a wear-resistant coating material of titanium-carbon nano-multilayer composite includes the following steps:

[0044] S010: Prepare a 3D-printed titanium alloy as the substrate material, place the substrate material on the equipment sample rack, rotate the sample rack to the front of the anode layer linear ion beam, introduce argon (Ar) into the anode layer linear ion beam and ionize it, set a constant current of 0.2 A, set the argon flow rate to 48 - 50 sccm, and perform pretreatment (etching) on the substrate material to remove the surface oxide film;

[0045] S020: The Ti-TiN layer with the characteristic of interface fusion is prepared by alternately using cathodic arc ion plating and anode layer ion beam, and the set thickness of the prepared Ti-TiN layer is 2.5 - 3.0 μm;

[0046] S021: Set a constant current, set the argon gas flow rate as f1, and deposit on the substrate material for a time of t1 to prepare a Ti layer;

[0047] S022: Set a constant current, set the nitrogen gas flow rate as f2, and deposit on the Ti layer for a time of t2 to prepare a TiN layer; then reduce the nitrogen gas input at a speed of f3 / min and introduce argon gas at a speed of f4 / min, and gradually change the two gases to make the TiN layer transition to the Ti layer, with a duration of t3;

[0048] S023: Set a constant current, set the argon gas flow rate as f1, and deposit for a time of t4 to prepare a Ti layer; reduce the argon gas input at a speed of f4 / min and increase the nitrogen gas input at a speed of f3 / min, and gradually change the two gases to make the Ti layer transition to the TiN layer until a TiN layer is prepared, with a duration of t5;

[0049] Among them, the argon gas flow rate f1 is less than the nitrogen gas flow rate f2; the gas flow rate f3 / min is greater than the gas flow rate f4 / min;

[0050] Among them, the argon gas flow rate f1 is 200 sccm; the deposition time t1 is 20 minutes; the nitrogen gas flow rate f2 is 450 sccm; the deposition time t2 is 5 minutes; the gas flow rate f3 / min is 90 sccm / min; the time t3 is 5 minutes; the gas flow rate f4 / min is 40 sccm / min; the time t4 is 10 minutes; the time t5 is 10 minutes;

[0051] Repeat S022 - S023 to make the last layer prepared be a Ti layer;

[0052] S030: Rotate the sample holder to the front of the anode layer ion beam, set a constant current, set the C2H2 gas flow rate as 48 - 50 sccm, and deposit for 30 minutes to prepare an amorphous carbon (DLC) lubricating layer.

[0053] Beneficial technical effects:

[0054] It is unacceptable for the artificial joint surface protective coating material to prematurely spall and fail during the service process under the coupled action of friction and corrosion in the human body. The fundamental reason for its spalling failure is that the coating has too high internal stress and insufficient bonding force with the substrate. Therefore, based on the above situation, the present invention proposes a composite structure idea that integrates a strengthened substrate surface bonding layer, an intermediate energy absorption layer with an interfacial fusion structure, and a top lubricating layer, and successfully prepares a titanium-carbon composite protective coating material with multi-layer interfacial fusion characteristics based on an alternating and gradual arc ion plating technology. The specific technical solution is as follows.

[0055] First, an arc ion plating technology with a high ionization rate and high ion energy is proposed to first prepare a Ti layer capable of achieving metallurgical bonding on the surface of the artificial joint prosthesis as a bonding layer to improve the bonding performance of the overall coating. Subsequently, a TiN-Ti layer with interfacial fusion characteristics is periodically deposited on its surface as an energy absorption layer to reduce the internal stress of the overall coating, and at the same time effectively slow down the stress cracking phenomenon generated during the friction impact process, thereby avoiding the brittle fracture and spalling phenomenon of the entire coating when subjected to an impact. The reasons for choosing the TiN-Ti layer with interfacial fusion characteristics are as follows: The Ti layer is relatively soft and has mechanical properties equivalent to those of the substrate material, while the TiN layer has extremely high hardness and belongs to a hard ceramic layer. By gradually and periodically changing the introduction of the reaction gases Ar-N2 during the deposition process, a TiN-Ti layer structure with interfacial fusion characteristics can be achieved. This structure does not have an obvious interlayer interface structure, but has the characteristics of an alternating structure of soft (Ti layer)-hard (TiN), which can effectively absorb and release the stress transmitted by the joint surface when the joint faces instantaneous impacts (such as human jumping and running), and avoid the failure of the entire coating due to the formation of through cracks. Finally, a smooth and dense amorphous carbon layer is prepared as the top lubricating layer on the top of the multi-layer structure using the anode ion beam deposition technology. The present invention particularly proposes that based on setting a specific thickness range, by changing the deposition time, a variety of materials with interfacial fusion characteristics and alternating deposition of Ti-TiN layers are prepared, and the multi-layer structure material with the best comprehensive effect is screened out through experiments.

[0056] The wear-resistant coating material of the titanium-carbon nano multi-layer composite prepared by the present invention has improved hardness and wear resistance compared with other nitride-based coating wear-resistant coating materials, and also has good energy absorption characteristics, which can slow down the stress cracking and peeling phenomenon of the coating under impact conditions.

[0057] Compared with other wear-resistant coating preparation technologies, the alternating and gradual arc ion plating technology proposed by the present invention has a large design range for the composite structure coating material, high process controllability, and the prepared coating material can be used as the final state of the product without other additional processing (such as polishing) process. Brief Description of the Drawings

[0058] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts do not necessarily draw to actual scale. Obviously, the following-described drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0059] Figure 1 Schematic diagram of the structure of the vacuum coating equipment used in the present invention (the left side is the cathode arc target, and Ti and TiN layers are prepared by controlling the type of gas introduced. The right side is the anode layer ion source, and acetylene is introduced to prepare the top amorphous carbon layer);

[0060] Figure 2 Schematic diagram of the structure of the titanium-carbon multi-layer coating prepared in Example 1 of the present invention (the middle layer Ti:TiN = 5:5);

[0061] Figure 3 Schematic diagram of the structure of the titanium-carbon multi-layer coating prepared in Example 2 of the present invention (the middle layer Ti:TiN = 3:3);

[0062] Figure 4 Schematic diagram of the structure of the titanium-carbon multi-layer coating prepared in Example 3 of the present invention (the middle layer Ti:TiN = 1:1);

[0063] Figure 5 Schematic diagram of the structure of the Ti-TiN multi-layer coating without the top amorphous carbon layer prepared in Example 4 of the present invention (Ti:TiN = 4:4);

[0064] Figure 6 Cross-sectional structure morphology diagram and energy spectrum line scan results of the Ti / TiN / amorphous carbon multi-layer coating with the characteristics of interface fusion prepared in Example 2 of the present invention;

[0065] Figure 7 Cross-sectional structure morphology diagram and energy spectrum line scan results of the Ti / TiN / amorphous carbon multi-layer coating with the characteristics of interface fusion prepared in Example 3 of the present invention;

[0066] Figure 8 Cross-sectional and surface structure morphology diagrams of the Ti / TiN multi-layer coating prepared in Example 4 of the present invention;

[0067] Figure 9 Tribological curves and wear rate results when the coating samples prepared in different embodiments of the present invention and the 3D printed titanium alloy substrate are respectively rubbed against the polytetrafluoroethylene material;

[0068] Figure 10This is the test for the bonding strength of the titanium-carbon multi-layer coating prepared in Example 1 of the present invention. Detailed implementation mode

[0069] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0070] As used herein, "and / or" includes any and all combinations of one or more of the listed related items.

[0071] As used herein, "a plurality of" means two or more, that is, it includes two, three, four, five, etc.

[0072] As used in this specification, the term "about" typically represents + / - 5% of the stated value, more typically + / - 4% of the stated value, more typically + / - 3% of the stated value, more typically + / - 2% of the stated value, even more typically + / - 1% of the stated value, and even more typically + / - 0.5% of the stated value.

[0073] In this specification, certain embodiments may be disclosed in a format within a certain range. It should be understood that this kind of description "within a certain range" is only for convenience and brevity, and should not be construed as a rigid limitation on the disclosed range. Therefore, the description of the range should be considered to have specifically disclosed all possible sub-ranges and individual numerical values within this range. For example, the description of the range 1-6 should be regarded as having specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and individual numbers within this range, such as 1, 2, 3, 4, 5, and 6. The above rules apply regardless of the breadth of the range.

[0074] The "interface fusion characteristic" described in the present invention means that there is no obvious interface structure between the prepared TiN layer and Ti layer, and the contrast difference between the two has a gradual change characteristic.

[0075] The titanium-carbon composite layer prepared by the present invention has the following characteristics.

[0076] Good hardness: The intermediate Ti / TN coating has a very high hardness, usually between 2000-3000HV, which is higher than the hardness of many metal and non-metal materials. By adjusting the ratio and interface structure of the two, a good combination of hardness and toughness can be achieved.

[0077] Good wear resistance: Due to its high hardness, the titanium nitride coating has excellent wear resistance, which can significantly extend the service life of the substrate.

[0078] Good corrosion resistance: The titanium nitride coating shows excellent corrosion resistance in many corrosive media, which helps to protect the substrate from corrosion.

[0079] Amorphous carbon coating: Amorphous carbon is a type of solid lubricating coating material with high hardness (the hardness of the amorphous carbon coating prepared by PVD technology can reach up to more than 40 GPa), good chemical stability (no chemical corrosion occurs in any solution), and self-lubricating characteristics, and has important applications in the aerospace field. In Example 4 of the present invention, the friction coefficient of the sample without the top amorphous carbon coating is about 0.4, which is significantly higher than the friction coefficient of about 0.1 - 0.2 of the sample with the amorphous carbon coating (Examples 1 - 3), proving that the amorphous carbon coating has self-lubricating characteristics.

[0080] Example 1

[0081] This example provides a multi-layered titanium-carbon composite coating material, using the Figure 1 shown vacuum coating equipment. The coating structure prepared in this example is as Figure 2 shown, and the specific preparation process is as follows.

[0082] 1. Substrate material preparation

[0083] Using 3D printed titanium alloy as the substrate material, the substrate is polished before coating. The size of the substrate material is 17 mm × 17 mm × 3 mm. Before depositing the coating, first place the 3D printed and polished titanium alloy substrate in anhydrous ethanol and acetone respectively for ultrasonic cleaning for 15 minutes to remove the oil and other impurities on its surface; then use a hair dryer to dry the residual liquid on the surface and set it aside for use.

[0084] 2. Substrate material pretreatment

[0085] Sample clamping. Place the 3D printed titanium alloy substrate after the above pretreatment on the sample holder, and use a special fixture to fix the sample so that it is firmly fixed on the sample holder and can conduct electricity well with the sample holder. After placing the sample holder in the coating chamber of the equipment, first use a mechanical pump and a molecular pump to evacuate the chamber, and control the chamber pressure to be lower than 2.0×10 -5 Torr, and then perform the pretreatment before sample coating (i.e., sample etching pretreatment).

[0086] Sample etching pretreatment. After the vacuum degree of the vacuum chamber reaches the set value, open the chamber and heat it to 200 °C. After the temperature reaches the set value, start the etching treatment. Pass argon into the anode layer linear ion beam and ionize it, and use the ionized energetic Ar +Etch and clean the surface of the ion pair matrix material to remove the oxide film formed on the sample surface in the air, so as to increase the bonding strength between the subsequent coating material and the matrix material. The specific treatment process is as follows:

[0087] Set the ion beam current: 0.2 A;

[0088] Ar gas flow rate: 48 - 50 sccm. Keep the chamber pressure constant at 2.0 mTorr by adjusting the gas flow, and the output power is 120 W;

[0089] Substrate negative bias voltage: -100 V;

[0090] Etching time: 30 min.

[0091] 3. Preparation of the intermediate energy absorption layer (coating)

[0092] Ti layer (bonding layer): Set the cathode arc target current to 70 A, the argon gas flow rate to 200 sccm (f1), control the chamber pressure to 45 mTorr, the substrate negative bias voltage to -60 V, and the chamber temperature to 200℃ - 230℃. The deposition time is 20 minutes (t1).

[0093] TiN layer: Set the cathode arc target current to 70 A, the nitrogen gas flow rate to 450 sccm (f2), control the chamber pressure to 45 mTorr, the substrate negative bias voltage to -60 V, and the chamber temperature to 200℃ - 230℃. First, deposit a pure TiN layer for 5 minutes (t2), and then within 5 minutes (t3), reduce the nitrogen gas introduction at a rate of 90 sccm / minute (f3) and introduce argon gas at a rate of 40 sccm / minute (f4). Through the gradual change of the two gases, on the premise of ensuring stable target discharge, realize the interface fusion preparation of the TiN - Ti layer. The total duration is 10 minutes.

[0094] Ti layer: Set the cathode arc target current to 70 A, the argon gas flow rate to 200 sccm (f1), control the chamber pressure to 45 mTorr, the substrate negative bias voltage to -60 V, and the chamber temperature to 200℃ - 230℃. The deposition time is 10 minutes (t4). Then reduce the argon gas at a rate of 40 sccm / minute (f4) and gradually introduce nitrogen gas at a rate of 90 sccm / minute (f3) to gradually realize the preparation from a pure Ti layer to a pure TiN layer. The duration is 10 minutes (t5).

[0095] Repeat the above steps.

[0096] Top amorphous carbon layer: Rotate the sample holder to the front of the anode layer ion beam through revolution rotation. Set the ion beam current to 0.2 A, the C2H2 gas flow rate: 48 - 50 sccm. Keep the chamber pressure constant at 2.0 mTorr by adjusting the gas flow, the output power is 120 W, the substrate negative bias voltage: -100 V, and the deposition time is 30 minutes.

[0097] Through the above preparation process, a composite coating structure with a Ti bonding layer, a 5 - cycle interface fusion structure Ti - TiN intermediate layer, and a top amorphous carbon lubricating layer is finally achieved.

[0098] In this example, the thickness of the Ti bonding layer is 0.6μm (multiplied by 2), the thickness of the alternating TiN - Ti layers in the middle is 1.6μm, and the thickness of the top layer is 0.5μm, with a total thickness of approximately 3.3μm.

[0099] Example 2

[0100] This example provides another example of a titanium - carbon composite coating material.

[0101] In the preparation process adopted in this example, the preparation and pretreatment of the substrate material involved are the same as those in Example 2, except that the number of layers and deposition time of the intermediate layer are different. The obtained coating structure is as Figure 3 shown.

[0102] The preparation of the intermediate energy absorption layer (coating) is as follows:

[0103] Ti layer (bonding layer): Set the cathode arc target current to 70A, the argon gas flow rate 200 sccm (f1), control the chamber pressure at 45 mTorr, the substrate negative bias voltage -60 V, and the chamber temperature 200℃ - 230℃. The deposition time is 20 minutes (t1).

[0104] TiN layer: Set the cathode arc target current to 70A, the nitrogen gas flow rate 450 sccm (f2), control the chamber pressure at 45mTorr, the substrate negative bias voltage -60 V, and the chamber temperature 200℃ - 230℃. First, deposit a pure TiN layer for 10 minutes (t2), and then within 10 minutes (t3), reduce the nitrogen gas introduction at a rate of 45sccm / minute (f3), and introduce argon gas at a rate of 20sccm / minute (f4). Through the gradual change of the two gases, on the premise of ensuring stable target discharge, the interface fusion preparation of the TiN - Ti layer is achieved. The total duration is 20 minutes.

[0105] Ti layer: Set the cathode arc target current to 70 A, the argon gas flow rate to 200 sccm (f1), control the chamber pressure at 45 mTorr, the substrate negative bias voltage to -60 V, the chamber temperature to 200°C - 230°C, and the deposition time to 10 minutes (t4). Subsequently, within 10 minutes (t5), reduce the argon gas at a rate of 20 sccm / minute (f4), and gradually introduce nitrogen gas at a rate of 45 sccm / minute (f3), gradually transitioning from the pure Ti layer to the preparation of the pure TiN layer.

[0106] Taking Ti-TiN as one deposition cycle, deposit a total of 3 cycles to obtain a structure as Figure 3 shown, with a structure of an intermediate layer having 3 cycle structures.

[0107] Top amorphous carbon layer: Rotate the sample holder through revolution to the front of the anode layer ion beam. Set the ion beam current to 0.2 A, the C2H2 gas flow rate: 48 - 50 sccm. Keep the chamber pressure constant at 2.0 mTorr by adjusting the gas flow, the output power at 120 W, the substrate negative bias voltage: -100 V, and the deposition time at 30 minutes.

[0108] In this example, the thickness of the Ti bonding layer is 0.6 μm (multiplied by 2), the alternating TiN-Ti layer in the middle has a thickness of 1.6 μm, and the top layer has a thickness of 0.5 μm, with a total thickness of approximately 3.3 μm.

[0109] Example 3

[0110] Based on Example 3, this example presents another improved example of the preparation of titanium nitride coating materials.

[0111] In the preparation process adopted in this example, the preparation and pretreatment of the substrate material involved are the same as in Example 3, with the difference being the number of intermediate layers and the deposition time. The obtained coating structure is as Figure 4 shown.

[0112] Optimized process parameters:

[0113] Ti layer (bonding layer): Set the cathode arc target current to 70 A, the argon gas flow rate to 200 sccm (f1), control the chamber pressure at 45 mTorr, the substrate negative bias voltage to -60 V, and the chamber temperature to 200°C - 230°C. The deposition time is 20 minutes (t1).

[0114] TiN layer: Set the cathode arc target current to 70 A, the nitrogen gas flow rate to 450 sccm (f2), control the chamber pressure to 45 mTorr, the substrate negative bias voltage to -60 V, the chamber temperature to 200°C - 230°C, and deposit a pure TiN layer for 20 minutes (t2). Subsequently, within 10 minutes (t3), reduce the nitrogen gas introduction at a rate of 45 sccm / minute (f3), introduce argon gas at a rate of 20 sccm / minute (f4), and gradually change the two gases to achieve the interfacial fusion preparation of the TiN-Ti layer while ensuring stable target discharge. The total duration is 30 minutes.

[0115] Ti layer: Set the cathode arc target current to 70 A, the argon gas flow rate to 200 sccm (f1), control the chamber pressure to 45 mTorr, the substrate negative bias voltage to -60 V, the chamber temperature to 200°C - 230°C, and the deposition time to 10 minutes (t4). Subsequently, reduce the argon gas at a rate of 20 sccm / minute (f4) and gradually introduce nitrogen gas at a rate of 45 sccm / minute (f3) to gradually prepare from a pure Ti layer to a pure TiN layer for 10 minutes (t5).

[0116] Top amorphous carbon layer: The ion beam current is 0.2 A, the C2H2 gas flow rate is 48 - 50 sccm, keep the chamber pressure constant at 2.0 mTorr by adjusting the gas flow, the output power is 120 W, the substrate negative bias voltage is -100 V, and the deposition time is 30 minutes.

[0117] It can be understood that taking Ti-TiN as one deposition cycle, according to needs, n deposition cycles can also be deposited to prepare titanium nitride coating materials.

[0118] Example 4

[0119] This example provides an equipment operation example of a titanium nitride coating without a top amorphous carbon layer.

[0120] Based on Example 1, this example presents another preparation example of a titanium nitride coating material without a top amorphous carbon coating, with differences in the number of intermediate layers and deposition time. The prepared coating structure is as Figure 5 shown.

[0121] Ti layer: Set the cathode arc target current to 70 A, the argon gas flow rate to 200 sccm (f1), control the chamber pressure to 45 mTorr, the substrate negative bias voltage to -60 V, the chamber temperature to 200°C - 230°C, and the deposition time to 15 minutes (t1).

[0122] TiN layer: Set the cathode arc target current to 70 A, the nitrogen flow rate to 450 sccm (f2), control the chamber pressure at 45 mTorr, the substrate negative bias voltage at -60 V, the chamber temperature at 200 °C - 230 °C, and the deposition time at 13 minutes (t2).

[0123] Take the above Ti-TiN layer as one cycle, and deposit a total of 4 cycles.

[0124] Top TiN layer: The process parameters are the same as those for the preparation of the second TiN layer, and the deposition time is extended to 30 minutes to increase the thickness. Finally, a nitride composite coating material with an alternating Ti-TiN structure is formed.

[0125] Example 5

[0126] This example provides performance tests for multiple coating materials prepared previously.

[0127] 1. Coefficient of friction

[0128] Take the coating materials prepared in Examples 1 - 4, and the 3D printed titanium alloy substrate material used as a control test group, conduct friction and wear performance tests, and the results of the measured coating friction coefficients and wear rates are shown in Table 1 and Figure 9 .

[0129] Table 1 Coefficient of friction

[0130]

[0131] As can be seen from the results in Table 1, for the samples with composite coatings prepared (Examples 1 - 4), their coefficients of friction and wear rates are significantly lower than those of the substrate titanium alloy material, indicating that the coating can indeed significantly reduce the wear of the substrate material. Further, it can be intuitively seen from the coefficient of friction curve Figure 9 that after preparing an amorphous carbon layer on the top layer, the coefficient of friction of the coating is lower than that of the sample with a TiN coating on the top layer, indicating that preparing lubricating amorphous carbon on the top layer can further reduce wear. Furthermore, from the trend of the coefficient of friction curve, it can be seen that the titanium-carbon composite coating with a Ti:TiN ratio of 5:5 in the middle layer has the lowest coefficient of friction, and the curve is smooth and flat during the entire friction process with very small fluctuations. While the coefficients of friction of the titanium-carbon composite coatings with other middle layer ratios show a gradually increasing trend with obvious fluctuations. These fluctuations indicate that the middle layer of the coating cannot continuously provide a good stress absorption effect during the friction process, resulting in instantaneous cracking of the local coating, which will accelerate the failure of the coating. This shows that the "interface fusion characteristic" structure of multiple layers can better absorb external stress. It can be seen from the wear rate that this multi-layered titanium-carbon composite coating can reduce the wear rate by two orders of magnitude, significantly reducing the wear of the substrate material.

[0132] From the above indicators of the tribological properties of the coating, it can be seen that the sample of the titanium-carbon composite coating with a multi-layer structure (the ratio of Ti:TiN in the intermediate layer is 5:5) proposed by the present invention can significantly reduce the wear of the substrate, inhibit the peeling of the coating during long-term wear, and thus extend the service life of the coating.

[0133] 2. Coating structure characterization test

[0134] Figure 6 This is the cross-sectional structure morphology diagram and energy dispersive spectroscopy line scan result of the Ti / TiN / amorphous carbon multi-layer coating with the characteristics of interface fusion prepared in Example 1 of the present invention. It can be seen from the figure that there is no obvious interface structure between the middle dark part (TiN layer) and the light part (Ti layer), and the contrast difference between the two has a gradual change characteristic, indicating that the interface structure has the characteristics of fusion. The total thickness of the coating is about 3.3 μm, and there are no defects such as interlayer cracking in the coating.

[0135] Figure 7 This shows the cross-sectional structure morphology diagram and energy dispersive spectroscopy line scan result of the Ti / TiN / amorphous carbon multi-layer coating with the characteristics of interface fusion prepared in Example 3 of the present invention. From the SEM result of the coating cross-section, the figure shows that the total thickness of the coating is about 3.4 μm, the surface of the coating interface is complete, and the energy dispersive spectroscopy result of the elemental surface distribution shows that the compositional transition characteristics between the Ti-TiN layers are obvious, and the contrast difference between the two has a gradual change characteristic, indicating that the interface structure has the characteristics of fusion.

[0136] Figure 8 This is the SEM result of the multi-layer titanium nitride coating of the amorphous carbon coating without a top layer prepared in Example 4 of the present invention. The figure shows that it is composed of a multi-layer structure. The total thickness of the coating is about 1.82 μm, the thickness of the Ti layer is 280 nm, and the thickness of the middle TiN layer is 300 nm. The surface of the coating interface is complete, and there is no interlayer cracking phenomenon. However, the overall surface of the coating is relatively rough and there are many large particle defects, which is one of the disadvantages of the coating prepared by the ordinary arc ion plating technology; and the compositional transition characteristics between the Ti-TiN layers are not obvious, indicating that the interface structure does not have the characteristics of fusion.

[0137] 3. Coating mechanical property test

[0138] The nano-indentation test technology was used to test the mechanical properties of the coating, and the test results are shown in Table 2 as statistically presented. Through comparison, it was found that the hardness of the coatings in Examples 1-4 all exceeded 13 GPa, which was significantly higher than the 3.5 GPa of the 3D printed titanium alloy matrix material. This indicates that the coating can significantly improve the hardness of the matrix titanium alloy. In addition, the hardness of the samples with the top amorphous carbon coating (Examples 1-3) was higher than that of the sample in Example 4 without the top amorphous carbon. Moreover, the more the number of periods with the characteristic of interface fusion in the multi-layer structure, although the overall hardness of the sample decreased to a certain extent, the elastic modulus increased and the toughness of the surface coating was improved, which would be beneficial for the coating to avoid brittle fracture and improve the overall service life of the coating.

[0139] Table 2 Test results of the mechanical properties of the coating and the matrix material

[0140]

[0141] 4. Test on the bonding performance between the coating and the matrix

[0142] Figure 10 This is the bonding strength test of the titanium-carbon multi-layer coating prepared in Example 1 of the present invention (the intermediate layer Ti:TiN = 5:5). The results showed that the bonding force of the multi-layer titanium-carbon composite coating prepared by the alternating gradient arc ion plating technology reached 32 N, indicating good bonding performance; the bonding strength of the general amorphous carbon coating was about 20 N.

[0143] It should be noted that in this article, the term "including", "comprising" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or further includes elements inherent to such process, method, article or device. Without more limitations, the element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including that element.

[0144] The embodiments of the present invention have been described above in conjunction with the accompanying drawings. However, the present invention is not limited to the above specific embodiments. The above specific embodiments are merely illustrative and not restrictive. Under the inspiration of the present invention, those of ordinary skill in the art can also make many forms without departing from the purpose of the present invention and the scope protected by the claims. All of these fall within the protection scope of the present invention.

Claims

1. A preparation method of a wear-resistant coating material with a titanium-carbon nano-multilayer composite, characterized in that, It includes the following steps: S010: Prepare titanium alloy for 3D printing as the substrate material, place the substrate material on the equipment sample rack, rotate the sample rack to the front of the anode layer linear ion beam, introduce argon gas into the anode layer linear ion beam to ionize it, and pre-treat the substrate material to remove the surface oxide film; S020: Alternately use cathode arc ion plating and anode layer ion beam to prepare an intermediate energy absorption layer Ti-TiN layer with the characteristics of interface fusion, and set the thickness of the prepared Ti-TiN layer to 1.6 μm; S021: Set a constant current, set the cathode arc target current to 70 A; set the argon gas flow rate to f1, and deposit on the substrate material for a time of t1 to prepare a Ti layer; S022: Set a constant current, set the cathode arc target current to 70 A; Set the nitrogen gas flow rate to f2, deposit on the Ti layer for a time of t2 to prepare a TiN layer; then reduce the nitrogen gas introduction at a rate of f3 / min and introduce argon gas at a rate of f4 / min, and gradually change through the two gases to make the TiN layer transition to the Ti layer, with a duration of t3; S023: Set a constant current, set the cathode arc target current to 70 A; set the argon gas flow rate to f1, deposit for a time of t4 to prepare a Ti layer; reduce the argon gas introduction at a rate of f4 / min and increase the nitrogen gas introduction at a rate of f3 / min, and gradually change through the two gases to make the Ti layer transition to the TiN layer, with a duration of t5; Among them, the argon gas flow rate f1 is less than the nitrogen gas flow rate f2; the gas flow rate f3 / min is greater than the gas flow rate f4 / min; Among them, the argon gas flow rate f1 is 200 sccm; the deposition time t1 is 20 minutes; the nitrogen gas flow rate f2 is 450 sccm; the deposition time t2 is 5 minutes; the gas flow rate f3 / min is 90 sccm / min; the time t3 is 5 minutes; the gas flow rate f4 / min is 40 sccm / min; the time t4 is 10 minutes; the time t5 is 10 minutes; Repeat S022 - S023 to prepare 5 cycles of the interface fusion structure Ti-TiN intermediate layer, where the layer ratio of the Ti layer to the TiN layer is 5:5, and make the last prepared layer be the Ti layer; S030: Rotate the sample rack to the front of the anode layer ion beam, set a constant current, set the ion beam current to 0.2 A; set the C2H2 gas flow rate to 40 - 50 sccm, and deposit for 30 - 40 minutes to prepare an amorphous carbon lubricating layer.

2. The preparation method according to claim 1, characterized in that, When pre-treating the substrate material, set a constant current, set the argon gas flow rate to 40 - 50 sccm; set the equipment cavity temperature to not less than 200 °C, set the cavity air pressure to be constantly 2.0 mTorr; the deposition time is 20 - 30 minutes.

3. The preparation method according to claim 1, characterized in that, In S021, set the equipment cavity temperature to not less than 200 °C, and set the cavity air pressure to 40 - 50 mTorr.

4. The preparation method according to claim 1, characterized in that, In S022, set the equipment cavity temperature to not less than 200 °C, and set the cavity air pressure to 40 - 50 mTorr.

5. The titanium-carbon nano-multilayer composite wear-resistant coating material prepared by the preparation method according to any one of claims 1 to 4, characterized in that: The wear-resistant coating material of the titanium-carbon nano-multilayer composite consists of a substrate material, an intermediate energy absorption layer, and a top amorphous carbon lubricating layer from bottom to top; the intermediate energy absorption layer is Ti-TiN with the characteristic of interface fusion; the overall thickness of the wear-resistant coating material of the titanium-carbon nano-multilayer composite is 3-3.5 μm.

6. The wear-resistant coating material of titanium-carbon nano multi-layer composite according to claim 5, characterized in that, A Ti layer is used as a bonding layer between the substrate material and the intermediate energy absorption layer; a Ti layer is used as a bonding layer between the top amorphous carbon lubricating layer and the intermediate energy absorption layer.

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