Antifriction wear-resistant Zr / ZrN / ZrCuN composite coating as well as preparation method and application thereof

Abstract

The invention provides an antifriction wear-resistant Zr / ZrN / ZrCuN composite coating as well as a preparation method and application thereof, and relates to the technical field of surface coating materials. The invention provides an antifriction wear-resistant Zr / ZrN / ZrCuN composite coating which comprises a Zr bonding layer, a ZrN supporting layer, a ZrN transition layer and a ZrCuN composite layer which are sequentially stacked, and the ZrCuN composite layer comprises a ZrN ceramic phase and doped Cu. The Zr / ZrN / ZrCuN composite coating provided by the invention has the advantages of high plastic deformation resistance, low friction coefficient, high wear resistance, good film-substrate binding force and excellent comprehensive performance, can prolong the service life and improve the functions of medical metal materials such as titanium alloy and the like, and is completely suitable for the surface protection requirements of medical apparatuses and instruments, tools and molds and mechanical parts.

Description

Technical Field

[0001] The invention relates to the technical field of surface coating materials, and in particular to a friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating and a preparation method and application thereof. Background Art

[0002] Lubricating and hard coatings prepared by physical vapor deposition (PVD) technology, especially transition metal nitride coatings, have the advantages of high hardness and elastic modulus, high chemical inertness, high thermal stability, etc., which can significantly reduce the friction and wear of workpieces and enhance the surface corrosion resistance, thereby greatly improving the performance, reliability and service life of tools and mechanical parts. Therefore, binary and ternary metal nitride hard coatings represented by TiN, CrN, CrAlN, TiAlN, etc. are widely used as surface protection materials in aerospace, machinery manufacturing, automotive industry, medical equipment and other fields.

[0003] Compared with the widely used TiN coating, ZrN is gold-resistant, has the advantages of high hardness, high melting point, low resistivity and good corrosion resistance, and can be used in non-ferrous metal processing, microelectronics industry, medical equipment and other industries. In particular, because Zr has no biological toxicity, corrosion resistance and good cell compatibility, ZrN is deposited as a medical coating on the surface of artificial joint prostheses, fracture internal fixators and orthopedic devices, which can greatly improve the corrosion resistance of medical metal materials such as titanium alloys and stainless steel in human body fluids, while enhancing the wear resistance of metal materials, reducing or even avoiding the toxic side effects of metal ions such as Al and V released due to corrosion and wear on the alloy surface, thereby extending the service life of the implant. However, the high friction coefficient (about 0.7), large internal stress, and insufficient wear resistance of ZrN-based coatings have seriously restricted their practical application.

[0004] The prior art discloses a Zr / Zr 2 The method of improving the corrosion and wear resistance of titanium alloy surface by using N / ZrN multilayer coating is mainly to use Zr intermediate layer to reduce coating defects, improve coating density, and preferentially produce passivation film to hinder the diffusion of corrosive medium and improve the corrosion resistance of coating. In addition, based on the composite or multilayer structure, doping metal components such as Ag and Cu in ZrN coating can greatly improve the antibacterial ability of medical devices. There are also literature reports on the use of arc ion plating to evaporate Zr target and Cu target to co-deposit ZrN / Cu composite coating. The coating shows excellent antibacterial properties against Escherichia coli and Bacillus, and has great application prospects in the field of medical devices. However, the addition of metal Cu can lead to poor wear resistance and corrosion resistance of the coating.

[0005] Therefore, developing a ZrN-based coating with good comprehensive properties such as high resistance to plastic deformation, strong interface bonding, low friction coefficient, and high wear resistance to improve the service life and function of medical metal materials such as titanium alloys is of great significance to expanding the functions and applications of hard coatings. Summary of the invention

[0006] In view of this, the purpose of the present invention is to provide a friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating. The Zr / ZrN / ZrCuN composite coating provided by the present invention has high resistance to plastic deformation, low friction coefficient, high wear resistance and good film-base bonding, and has excellent comprehensive performance.

[0007] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0008] The invention provides a friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating, comprising a Zr bonding layer, a ZrN supporting layer, a ZrN transition layer and a ZrCuN composite layer stacked in sequence, wherein the ZrCuN composite layer comprises a ZrN ceramic phase and doped Cu.

[0009] Preferably, the thickness of the Zr bonding layer is 0.05 to 0.2 μm;

[0010] The thickness of the ZrN support layer is 0.2 to 0.5 μm;

[0011] The thickness of the ZrN transition layer is 0.1 to 0.3 μm;

[0012] The thickness of the ZrCuN composite layer is 0.8-3 μm, and the mass content of Cu in the ZrCuN composite layer is 0.3-10%.

[0013] The present invention also provides a method for preparing the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating described in the above technical solution, comprising the following steps:

[0014] Arc ion plating is used to deposit a Zr bonding layer, a ZrN supporting layer and a ZrN transition layer on the substrate surface in sequence;

[0015] The ZrCuN composite layer is deposited on the surface of the ZrN transition layer by using arc ion plating and high-power pulse magnetron sputtering deposition to obtain the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating.

[0016] Preferably, the deposition method of the Zr bonding layer includes arc ion plating deposition, and the deposition process conditions of the Zr bonding layer include: the arc target material is a Zr target, the target operating current is 70 to 150A, the substrate bias is -30 to -150V, the argon gas flow rate is 100 to 500sccm, and the deposition time is 2 to 10min.

[0017] Preferably, the deposition method of the ZrN support layer includes arc ion plating deposition, and the deposition process conditions of the ZrN support layer include: the arc target is a Zr target, the target operating current is 70 to 150A, the substrate bias is -30 to -150V, the nitrogen flow rate is 400 to 1000sccm, and the deposition time is 10 to 15min.

[0018] Preferably, the deposition method of the ZrN transition layer includes arc ion plating deposition, and the deposition process conditions of the ZrN transition layer include: the arc target is a Zr target, the target operating current is increased from 80 to 100A to 110 to 160A, the nitrogen flow rate is reduced from 800 to 1000sccm to 200 to 400sccm, the substrate bias is increased from -60 to -90V to -120 to -180V, and the deposition time is 5 to 10min.

[0019] Preferably, the deposition method of the ZrCuN composite layer includes arc ion plating deposition and high-power pulsed magnetron sputtering deposition, and the deposition process conditions of the ZrCuN composite layer include: the arc target is a Zr target, the sputtering target is a Cu target, the arc target working current is 90 to 150A, the sputtering target power is 1 to 5kW, the substrate bias is -80 to -150V, the nitrogen flow rate is 300 to 500sccm, and the deposition time is 30 to 90min.

[0020] Preferably, the surface oxide layer of the substrate is removed before use;

[0021] The substrate comprises titanium alloy, stainless steel, high speed steel or cemented carbide.

[0022] Preferably, the removal of the surface oxide layer comprises ion etching; the process conditions of the ion etching include: an argon gas flow rate of 50 to 150 sccm argon, a substrate bias of -300 to -600 V, an ion source power of 3 to 8 kW, and an etching time of 30 to 120 min.

[0023] The present invention also provides the use of the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating described in the above technical solution or the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating prepared by the preparation method described in the above technical solution as a surface protection material.

[0024] In the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention, the structure of the Zr bonding layer-ZrN supporting layer-ZrN transition layer realizes the best adaptation of the film-base interface, so that the hardness and modulus transition from the substrate to the coating is smooth, the composite coating and the substrate (film base) interface bonding force are enhanced, the generation of columnar crystals is effectively reduced, the generation and expansion of cracks can be delayed, and the damage resistance of the coating under severe working conditions is improved. The composition of the ZrCuN composite layer includes a hard ZrN ceramic phase and doped soft metal Cu, which can effectively play the synergistic effect of soft-hard phases. Since Cu is not a nitride-forming element, it is located at the grain boundary of the hard phase ZrN in the composite coating, which not only plays a role in refining grains and pinning grain boundaries, but also can release the internal stress of the composite coating. When an external force acts on the composite coating, the metal Cu phase preferentially slides at the grain boundary, and the low shear force provided gives the composite coating excellent toughness and self-lubricity, while the hard ZrN ceramic phase provides high bearing capacity and wear resistance for the composite coating. Therefore, the Zr / ZrN / ZrCuN composite coating provided by the present invention has high resistance to plastic deformation, low friction coefficient, high wear resistance and good film-base bonding, and has excellent comprehensive performance. It can improve the service life and function of medical metal materials such as titanium alloys, and is fully suitable for the surface protection needs of medical devices, molds and mechanical parts.

[0025] The present invention adopts arc ion plating (AIP) deposition and high power pulsed magnetron sputtering (HiPIMS) deposition methods to prepare Zr / ZrN / ZrCuN composite coatings. Specifically, the AIP technology is used to deposit the Zr bonding layer, the ZrN supporting layer and the ZrN transition layer, and the AIP and HiPIMS composite technology is used to deposit the ZrCuN composite layer. The advantages of the AIP technology, namely, fast deposition rate, strong film-base bonding, and dense coating, and the advantages of the HiPIMS technology, namely, low deposition temperature and smooth coating surface without droplets, are combined. Moreover, based on the high metal ionization rate of HiPIMS, in the process of preparing the ZrCuN composite layer, metal Cu is doped in the ZrN matrix while utilizing the bombardment of glow discharge ions, thereby reducing the number and size of droplets generated during cathode arc discharge deposition of ZrN, and making the overall coating surface denser and smoother.

[0026] The ZrCuN composite layer deposited by the composite technology of AIP and HiPIMS of the present invention is composed of a hard ZrN ceramic phase and a doped soft metal Cu, which can effectively play the synergistic effect of soft-hard phases. Since copper is not a nitride-forming element, it is located at the grain boundary of the hard phase ZrN in the composite coating, and can inhibit the growth of ZrN grains during the deposition process, which not only plays a role in refining grains and pinning grain boundaries, but also can release the internal stress of the coating. When an external force acts on the coating, the metal Cu phase slips preferentially at the grain boundary, and the low shear force provided gives the coating excellent toughness and self-lubricity, while the hard ZrN matrix provides the coating with high bearing capacity and wear resistance. The Zr / ZrN / ZrCuN composite coating provided by the present invention has high resistance to plastic deformation, low friction coefficient, high wear resistance and good film-base bonding, and has excellent comprehensive performance.

[0027] Compared with the single arc technology for depositing ZrN coating, the present invention adopts AIP and HiPIMS composite deposition technology to realize the deposition of Zr / ZrN / ZrCuN composite coating under low temperature conditions (≤250°C) and low pressure (≤2.5Pa), which broadens the application scope of the substrate material and is fully suitable for the surface protection of medical devices, molds, and mechanical parts under harsh working conditions, especially meeting the technical requirements for surface strengthening of mold materials with low tempering critical temperature values.

[0028] Moreover, the preparation method provided by the present invention is simple and controllable, has a low deposition temperature, a short preparation cycle, and a low cost, and is suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of the substrate and the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating of the present invention;

[0030] Figure 2 Surface SEM images of the composite coatings in Example 2 and Comparative Example 1;

[0031] Figure 3 The cross-sectional SEM images of the composite coatings in Example 5 and Comparative Example 2;

[0032] Figure 4 XRD spectra of the titanium alloy substrate, the composite coating in Examples 1 to 3 and Comparative Example 1;

[0033] Figure 5 The friction coefficient curves of the composite coatings in Examples 1 to 3 and Comparative Example 1;

[0034] Figure 6 is a graph showing the wear rate of the composite coating in Examples 1 to 3 and Comparative Example 1;

[0035] Figure 7These are the Rockwell indentation and scratch morphology images of the composite coatings in Examples 4 to 6 and Comparative Example 2. DETAILED DESCRIPTION

[0036] The invention provides a friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating, comprising a Zr bonding layer, a ZrN supporting layer, a ZrN transition layer and a ZrCuN composite layer stacked in sequence, wherein the ZrCuN composite layer comprises a ZrN ceramic phase and doped Cu.

[0037] The structural schematic diagram of the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention is shown in Figure 1 , the following combination Figure 1 Provide detailed explanation.

[0038] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention includes a Zr bonding layer. In the present invention, the thickness of the Zr bonding layer is preferably 0.05 to 0.2 μm, and in specific embodiments can be 0.05 μm, 0.08 μm, 0.1 μm, 0.12 μm, 0.15 μm, 0.18 μm or 0.2 μm.

[0039] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention comprises a ZrN support layer located on the surface of the Zr bonding layer. In the present invention, the thickness of the ZrN support layer is preferably 0.2 to 0.5 μm, and in specific embodiments can be 0.2 μm, 0.25 μm, 0.3 μm, 0.35 μm, 0.4 μm, 0.45 μm or 0.5 μm.

[0040] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention comprises a ZrN transition layer located on the surface of the Zr support layer. In the present invention, the thickness of the ZrN transition layer is preferably 0.1 to 0.3 μm, and in specific embodiments can be 0.1 μm, 0.15 μm, 0.2 μm, 0.25 μm or 0.3 μm.

[0041] The Zr bonding layer-ZrN supporting layer-ZrN transition layer structure in the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention realizes optimal adaptation of the film-substrate interface, makes the hardness and modulus transition from the substrate to the coating smooth, enhances the film-substrate bonding force, effectively reduces the generation of columnar crystals, can delay the generation and expansion of cracks, and improves the damage resistance of the coating under severe working conditions.

[0042] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention comprises a ZrCuN composite layer located on the surface of the Zr transition layer, and the ZrCuN composite layer comprises a ZrN ceramic phase and doped Cu. In the present invention, the thickness of the ZrCuN composite layer is preferably 0.8-3 μm, and in a specific embodiment, it can be 0.8 μm, 1 μm, 1.2 μm, 1.5 μm, 1.8 μm, 2 μm, 2.2 μm, 2.5 μm, 2.8 μm or 3 μm; the mass content of Cu in the ZrCuN composite layer is preferably 0.3-10%, and in a specific embodiment, it can be 0.3%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%. The composition of the ZrCuN composite layer includes a hard ZrN ceramic phase and doped soft metal Cu, which can effectively exert the synergistic effect of soft-hard phases. Since Cu is not a nitride-forming element, it is located at the grain boundary of the hard phase ZrN in the composite coating, which not only refines the grains and pins the grain boundaries, but also relieves the internal stress of the composite coating. When external force acts on the composite coating, the metal Cu phase slips preferentially at the grain boundary, and the low shear force provided gives the composite coating excellent toughness and self-lubricity, while the hard ZrN ceramic phase provides the composite coating with high bearing capacity and wear resistance.

[0043] The Zr / ZrN / ZrCuN composite coating provided by the present invention has high resistance to plastic deformation, low friction coefficient, high wear resistance and good film-base bonding strength, can improve the service life and function of medical metal materials such as titanium alloys, and is fully suitable for the surface protection needs of medical devices, molds and mechanical parts.

[0044] The present invention also provides a method for preparing the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating described in the above technical solution, comprising the following steps:

[0045] Arc ion plating is used to deposit a Zr bonding layer, a ZrN supporting layer and a ZrN transition layer on the substrate surface in sequence;

[0046] The ZrCuN composite layer is deposited on the surface of the ZrN transition layer by using arc ion plating and high-power pulse magnetron sputtering deposition to obtain the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating.

[0047] Unless otherwise specified, the materials and equipment used in the present invention are all commercially available products in the art.

[0048] The invention adopts arc ion plating method to deposit a Zr bonding layer, a ZrN supporting layer and a ZrN transition layer on the surface of a substrate in sequence.

[0049] The invention adopts arc ion plating method to deposit a Zr bonding layer on the surface of the substrate.

[0050] In the present invention, the substrate preferably includes titanium alloy, stainless steel, high-speed steel or hard alloy. The present invention has no special limitation on the titanium alloy, stainless steel, high-speed steel and hard alloy, and titanium alloy, stainless steel, high-speed steel and hard alloy well known to those skilled in the art can be used. In the present invention, the substrate preferably removes the surface oxide layer before use, and the removal of the surface oxide layer preferably includes ion etching.

[0051] In the present invention, before the ion etching, it is preferred to further include: polishing and cleaning the substrate in sequence, clamping it on the coating machine frame, setting the rotating frame speed, evacuating the vacuum chamber, heating it, and then introducing argon gas for ion etching. The present invention has no special limitation on the polishing, and it can be polished to a mirror surface, such as mechanical grinding with sandpaper, mechanical grinding with sandpaper, and polishing with velvet polishing cloth in combination with diamond polishing agent to a mirror surface. In the present invention, the cleaning preferably includes acetone cleaning and anhydrous ethanol cleaning in sequence; the time of the acetone cleaning and anhydrous ethanol cleaning is preferably 10 to 30 minutes independently, and in a specific embodiment, it can be 10 minutes, 15 minutes, 20 minutes, 25 minutes or 30 minutes; the cleaning preferably includes ultrasonic cleaning. In the present invention, the rotating frame speed is preferably 1 to 3 r / min, and in a specific embodiment, it can be 1 r / min, 1.5 r / min, 2 r / min, 2.5 r / min or 3 r / min. In the present invention, the vacuum degree of the vacuum chamber after evacuation is preferably ≤5×10 -3 Pa. In the present invention, the temperature of the heated vacuum chamber is preferably 150-350°C, and in specific embodiments may be 150°C, 200°C, 250°C, 300°C or 350°C.

[0052] In the present invention, the process conditions of the ion etching preferably include: an argon gas flow rate of 50 to 150 sccm, which may be 60 sccm, 60 sccm, 70 sccm, 80 sccm, 90 sccm, 100 sccm, 110 sccm, 120 sccm, 130 sccm, 140 sccm or 150 sccm; a substrate bias of -300 to -600 V, which may be -300 V, 350 V, -400 V, 450 V, -500 V, 550 V or -600 V in a specific embodiment; an ion source power of 3 to 8 kW, which may be 3 kW, 4 kW, 5 kW, 6 kW, 7 kW or 8 kW in a specific embodiment; and an etching time of 30 to 120 min, which may be 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min or 120 min in a specific embodiment.

[0053] In the present invention, the deposition method of the Zr bonding layer preferably includes arc ion plating deposition (AIP), and the deposition process conditions of the Zr bonding layer preferably include: the arc target is a Zr target (pure metal Zr target); the target working current is 70 to 150A, and in a specific embodiment, it can be 70A, 80A, 90A, 100A, 110A, 120A, 130A, 140A or 150A; the substrate bias is -30 to -150V, and in a specific embodiment, it can be -30V, -40V, -50V, -60V, -70V, -80V, -90V, -100V, -110V, -120V, -130V, -140V, -150V, -160V, -170V, -180V, -190V, -200V, -210V, -220V, -230V, -240V, -250V, -260V, -270V, -280V, -290V, -30 ... 0V, -80V, -90V, -100V, -110V, -120V, -30V, -140V or -150V; the argon flow rate is 100-500sccm, and in a specific embodiment it can be 100sccm, 200sccm, 300sccm, 400sccm or 500sccm; the deposition time is 2-10min, and in a specific embodiment it can be 2min, 3min, 4min, 5min, 6min, 7min, 8min, 9min or 10min.

[0054] After obtaining the Zr bonding layer, the present invention uses arc ion plating to deposit a ZrN support layer on the surface of the Zr bonding layer. In the present invention, the deposition method of the ZrN support layer preferably includes arc ion plating deposition, and the deposition process conditions of the ZrN support layer preferably include: the arc target is a Zr target, the target working current is 70 to 150A, and in a specific embodiment, it can be 70A, 80A, 90A, 100A, 110A, 120A, 130A, 140A or 150A; the substrate bias is -30 to -150V, and in a specific embodiment, it can be -30V, -40V, -50V, -60V, -70V, -80V, - 90V, -100V, -110V, -120V, -30V, -140V or -150V; the nitrogen flow rate is 400-1000sccm, and in a specific embodiment, it can be 400sccm, 500sccm, 600sccm, 700sccm, 800sccm, 900sccm or 1000sccm; the deposition time is 10-15min, and in a specific embodiment, it can be 10min, 11min, 12min, 3min, 14min or 15min.

[0055] After obtaining the ZrN support layer, the present invention uses arc ion plating to deposit a ZrN transition layer on the surface of the ZrN support layer. In the present invention, the deposition method of the ZrN transition layer preferably includes arc ion plating deposition, and the deposition process conditions of the ZrN transition layer preferably include: the arc target is a Zr target; the target working current increases from 80 to 100A to 110 to 160A over time, and in a specific embodiment, it can increase from any one of 80A, 85A, 90A, 95A and 100A to any one of 110A, 120A, 130A, 140A, 150A and 160A; the increase rate of the target working current is preferably 3 to 5A / m in, which can be 3A / min, 3.5A / min, 4A / min, 4.5A / min or 4A / min in a specific embodiment; the nitrogen flow rate is reduced from 800-1000sccm to 200-400sccm over time, and can be reduced from any value among 800sccm, 850sccm, 900sccm, 950sccm and 1000sccm to 200sccm, 250sccm, 300sccm, 350sccm and 400sccm in a specific embodiment. any value of; the reduction rate of the nitrogen flow rate is preferably 80 to 100 sccm / min, and in a specific embodiment it can be 80 sccm / min, 85 sccm / min, 90 sccm / min, 95 sccm / min or 100 sccm / min; the substrate bias increases with time from -60 to -90 V to -120 to -180 V, and in a specific embodiment it can be increased from any one of -60 V, -65 V, -70 V, -75 V, -80 V, -85 V and -90 V to Any one of -120V, -125V, -130V, -135V, -140V, -145V, -150V, -155V and -160V; the increasing rate of the substrate bias is preferably 8-12V / min, and in a specific embodiment it can be 8V / min, 9V / min, 10V / min, 11V / min or 12V / min; the deposition time is 5-10min, and in a specific embodiment it can be 5min, 6min, 7min, 8min, 9min or 10min.

[0056] After the ZrN transition layer is obtained, the present invention deposits a ZrCuN composite layer on the surface of the ZrN transition layer by arc ion plating and high-power pulse magnetron sputtering deposition to obtain the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating.

[0057] In the present invention, the deposition method of the ZrCuN composite layer preferably includes arc ion plating deposition and high-power pulsed magnetron sputtering deposition, and the deposition process conditions of the ZrCuN composite layer preferably include: the arc target is a Zr target; the sputtering target (HiPIMS sputtering target) is a Cu target; the arc target working current is 90 to 150A, and in a specific embodiment, it can be 90A, 100A, 110A, 120A, 130A, 140A or 150A; the sputtering target power is 1 to 5kW, and in a specific embodiment, it can be 1kW , 2kW, 3kW, 4kW or 5kW; substrate bias is -80 to -150V, and in a specific embodiment it can be; nitrogen flow rate is 300 to 500sccm, and in a specific embodiment it can be -80V, -90V, -100V, -110V, -120V, -30V, -140V or -150V; deposition time is 30 to 90min, and in a specific embodiment it can be 30min, 40min, 50min, 60min, 70min, 80min or 90min.

[0058] After the deposition of the ZrCuN composite layer is completed, the present invention further comprises cooling to below 160°C.

[0059] The present invention also provides the use of the anti-friction and wear-resistant Zr / ZrN / ZrCuN composite coating described in the above technical solution or the anti-friction and wear-resistant Zr / ZrN / ZrCuN composite coating prepared by the preparation method described in the above technical solution as a surface protection material. In the present invention, the anti-friction and wear-resistant Zr / ZrN / ZrCuN composite coating can be used as a surface protection material for medical devices, molds, and mechanical parts under harsh working conditions, and can enhance the ability of the material surface to resist the external environment and working conditions; it can also be used as a surface strengthening material for mold materials with a low tempering critical temperature value (≤200°C), which can improve the surface performance of the material and enable it to function better under extreme conditions.

[0060] To further illustrate the present invention, the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating provided by the present invention and its preparation method and application are described in detail below in conjunction with embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0061] Example 1

[0062] (1) Cleaning the substrate: grind the titanium alloy mechanically with sandpaper, and polish it to a mirror surface using a velvet polishing cloth and a diamond polishing agent; ultrasonically clean the substrate in acetone for 15 min, ultrasonically clean it in anhydrous ethanol for 15 min, and then clamp it on the coating machine turntable, setting the turntable speed to 1 r / min.

[0063] (2) Vacuum heating: Turn on the mechanical pump + Roots pump + molecular pump vacuum pumping system and pump the vacuum chamber pressure to 5×10 -3 Pa below, and at the same time heat the vacuum chamber to 200°C.

[0064] (3) Ion etching: 80 sccm of argon gas was introduced into the vacuum chamber, a -450 V bias voltage was applied to the substrate, the ion source power was turned on, the ion source power was 6 kW, and the substrate was etched by bombarding with high-energy argon ions for 30 min.

[0065] (4) Deposition of Zr bonding layer (composed of Zr single substance) by AIP technology: 400 sccm of argon gas was introduced into the chamber, a -40 V bias voltage was applied to the substrate, the arc target power supply was turned on, a target current of 90 A was applied to the Zr target, and the Zr bonding layer was deposited for 5 min.

[0066] (5) Deposition of ZrN support layer by AIP technology: 800 sccm nitrogen was introduced into the chamber, the substrate bias voltage was -40 V, the arc target current was 90 A, and the ZrN support layer was deposited on the surface of the Zr bonding layer for 10 min.

[0067] (6) AIP technology was used to deposit the ZrN transition layer: the nitrogen flow rate in the chamber was gradually reduced from 800 sccm to 350 sccm at a rate of 90 sccm / min, the substrate bias was gradually increased from -40 V to -90 V at a rate of 10 V / min, and the Zr target current was gradually increased from 90 A to 110 A at a rate of 4 A / min. The deposition time was 5 min.

[0068] (7) Deposition of ZrCuN composite layer by AIP and HiPIMS composite technology: 350 sccm nitrogen was introduced into the chamber, the substrate bias was maintained at -90 V, the current of the Zr target was 110 A, and the HiPIMS power supply was turned on to sputter the Cu target with a sputtering power of 1.0 kW. The ZrCuN composite layer was deposited on the surface of the ZrN support layer, and a friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating was formed on the substrate surface. The deposition time was 30 min.

[0069] (8) Sampling: After deposition is completed, the system is turned off, the vacuum chamber is cooled to 150°C, and the sample is taken out.

[0070] Example 2

[0071] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating was prepared according to the method of Example 1, the only difference from Example 1 being that the sputtering power in step (7) was 1.5 kW.

[0072] Example 3

[0073] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating was prepared according to the method of Example 1, the only difference from Example 1 being that the sputtering power in step (7) was 2.0 kW.

[0074] Example 4

[0075] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating was prepared according to the method of Example 1, the only difference from Example 1 being that the substrate in step (1) was a cemented carbide substrate.

[0076] Example 5

[0077] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating was prepared according to the method of Example 2, which differs from Example 1 only in that the substrate in step (1) is a cemented carbide substrate.

[0078] Example 6

[0079] The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating was prepared according to the method of Example 3, which differs from Example 1 only in that the substrate in step (1) is a cemented carbide substrate.

[0080] Comparative Example 1

[0081] In order to compare the effect of doping Cu on the composite coating by composite deposition technology, a Zr / ZrN composite coating was prepared, and the ZrCuN composite layer in Example 1 was replaced by a ZrN top layer. The preparation method was different from that in Example 1 only in that:

[0082] Step (7) is replaced by: Prepare the ZrN top layer using AIP technology: introduce 450 sccm nitrogen into the chamber, apply a bias voltage of -90 V to the substrate, apply a Zr target current of 80 A, deposit the ZrN top layer on the surface of the ZrN support layer, and form a Zr / ZrN composite coating on the surface of the substrate. The deposition time is 30 min.

[0083] Comparative Example 2

[0084] The friction-reducing and wear-resistant Zr / ZrN composite coating was prepared according to the method of Comparative Example 1, the only difference from Comparative Example 1 being that the substrate in step (1) was a cemented carbide substrate.

[0085] Comparative Example 3

[0086] In order to compare the advantages of composite deposition technology over single arc technology, Zr / ZrN composite coating was prepared at high temperature using arc technology. The preparation method is as follows:

[0087] (1) Cleaning the substrate: Same as in Comparative Example 2.

[0088] (2) Vacuum heating: Turn on the mechanical pump + Roots pump + molecular pump vacuum pumping system and pump the vacuum chamber pressure to 5×10 -3 Pa below, and at the same time, the vacuum chamber is heated to 400°C.

[0089] (3) Ion etching: same as in Example 1.

[0090] (4) Deposition of ZrN bonding layer: 800 sccm nitrogen was introduced into the chamber, a -40 V bias was applied to the substrate, the arc target power supply was turned on, a target current of 80 A was applied to the Zr target, and the ZrN bonding layer was deposited for 10 min.

[0091] (5) Deposition of ZrN layer: 900 sccm nitrogen gas was introduced into the chamber, the substrate bias voltage was -120 V, the arc target current was 80 A, and a ZrN top layer was deposited on the surface of the ZrN bonding layer to form a Zr / ZrN composite coating on the substrate surface. The deposition time was 50 min.

[0092] (6) Sampling: After the deposition is completed, the system is turned off, the vacuum chamber is cooled to 150°C, and the sample is taken out.

[0093] Comparative Example 4

[0094] Zr / Zr 2 The specific preparation method of N / ZrN multilayer coating is as follows:

[0095] (1) The ground and polished Ti-6Al-4V titanium alloy material is ultrasonically cleaned for a certain period of time, rinsed with deionized water, and dried for later use.

[0096] (2) Place the treated titanium alloy sample on the substrate turntable, heat it to 380°C, and evacuate it to 10 -4 Pa, introduce Ar gas with an Ar gas flow rate of 400 sccm, turn on the Ti target, control the negative bias voltage to -200 V, and perform ion bombardment etching cleaning with an etching time of 40 min.

[0097] (3) Maintaining the deposition temperature, turning on the Zr target, and depositing the metal Zr layer; the substrate bias voltage was -60 V, and the target current of the metal Zr target was 130 A. The deposition was completed after 5 minutes.

[0098] (4) Keep the deposition temperature unchanged, turn off the Ar gas, and introduce a small amount of N 2 Gas, change pressure to 1Pa, N 2 The flow rate is 100 sccm, and Zr is deposited 2 N transition layer. The deposition time is 2 min.

[0099] (5) Keep the deposition temperature constant and further increase N 2 Gas, change the pressure to 5Pa, N2 The flow rate is 800 sccm, and the ZrN layer is deposited. The deposition time is 15 min, and the deposition of the ZrN layer is completed.

[0100] (6) Repeat the above process to alternately deposit Zr metal layer, Zr 2 N transition layer and ZrN layer, in order to ensure the Zr / Zr 2 The thickness of the N / ZrN multilayer coating is similar to that of the Zr / ZrN / ZrCuN composite coating prepared in Example 1. 2 The number of N transition layer and ZrN layer is 3.

[0101] Figure 2 Surface SEM images of the composite coatings in Example 2 and Comparative Example 1, Figure 3 The cross-sectional SEM images of the cemented carbide substrate-composite coating in Example 5 and Comparative Example 2 are shown in FIG. Figures 2-3 It can be seen that the surface of the Zr / ZrN / ZrCuN composite coating prepared in the embodiment is smoother and denser, the number of large particles on the surface is small, the cross-sectional structure of the Zr / ZrN / ZrCuN composite coating is dense, there are no columnar crystals, holes and large-sized droplets running through the entire coating, the film-substrate interface is well bonded, and there is no obvious interface between the substrate and the Zr binding layer, the ZrN support layer, the ZrN transition layer and the ZrCuN composite layer, and the ZrCuN composite layer. The surface of the Zr / ZrN composite coating prepared in the comparative example is rough, the number of large particles is large, and columnar crystals exist in the cross section.

[0102] Figure 4 From the XRD spectra of the titanium alloy substrate, the composite coatings in Examples 1 to 3 and Comparative Example 1, it can be seen that the Zr / ZrN / ZrCuN composite coatings prepared in the Examples are a composite structure comprising cubic ZrN and metallic Cu, while the Zr / ZrN composite coating in Comparative Example 1 is a ZrN structure.

[0103] The composite coatings prepared in Examples 4 to 6 and Comparative Example 2 were subjected to nanoindentation tests with a load of 5000 μN and a holding time of 2 seconds. The results are shown in Table 1.

[0104] The composite coatings prepared in Examples 1 to 3 and Comparative Examples 1, 3 to 4 were subjected to friction and wear tests. The friction pair was an Al2O3 tube with a diameter of Φ6. 2 O 3 ball, load is 1N, test time is 30min, results are shown in Figures 5-6 and Table 1.

[0105] Figure 5 is the friction coefficient curve of the composite coating in Examples 1 to 3 and Comparative Example 1, Figure 5As can be seen from Table 1, the friction coefficients of the Zr / ZrN / ZrCuN composite coatings are lower than those of the Zr / ZrN coatings prepared in Comparative Example 1, among which the composite coating prepared in Example 2 has the lowest friction coefficient, and the average steady-state friction coefficient is 0.52.

[0106] Figure 6 is a graph showing the wear rate of the composite coating in Examples 1 to 3 and Comparative Example 1. Figure 6 As shown in Table 1, the wear rates of the Zr / ZrN / ZrCuN composite coatings prepared in Examples 1 to 3 are lower than those of the Zr / ZrN composite coating prepared in Comparative Example 1. The wear rate of the composite coating prepared in Example 2 is 4.95×10 -6 mm 3 / (N·m), which is 79% lower than that of Comparative Example 1. 2 The N / ZrN multilayer coating has been worn through, so its wear rate has increased significantly.

[0107] The composite coatings prepared in Examples 4 to 6 and Comparative Example 2 were subjected to indentation and scratch bonding tests. The indentation test method used a diamond cone indenter with a load of 60 kgf. The bonding strength of the coating was determined by observing the indentation morphology. The scratch test was set with a maximum load of 100 N, a loading rate of 20 N / min, and a scratch length of 10 mm. The bonding strength of the coating was evaluated by observing the scratch morphology. The results are shown in Table 1. Figure 7 As shown in Table 1. Figure 7 As shown in Table 1, the Rockwell indentation grades of the composite coatings prepared in the embodiment and the comparative example are both HF-1, and the scratch test shows that the composite coating prepared in Example 2 has the highest bonding strength, which is 54N.

[0108] Table 1 Mechanical properties of the composite coatings prepared in the examples and comparative examples

[0109]

[0110] Note: “ / ” means not tested.

[0111] In summary, the comprehensive properties of the Zr / ZrN / ZrCuN composite coatings prepared in Examples 2 and 5 of the present invention, such as resistance to plastic deformation, friction coefficient, wear resistance and film-base bonding, are significantly better than those of the composite coatings prepared in the comparative examples. The present invention adopts AIP and HiPIMS composite deposition technology to prepare a Zr / ZrN / ZrCuN composite coating with a preferred orientation of the (200) crystal plane at a relatively low temperature. The coating structure is smoother and denser, without a columnar crystal structure, and is particularly suitable for surface protection of materials that are not resistant to high temperatures.

[0112] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating, comprising a Zr bonding layer, a ZrN supporting layer, a ZrN transition layer and a ZrCuN composite layer stacked in sequence, wherein the ZrCuN composite layer comprises a ZrN ceramic phase and doped Cu.

2. The friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating according to claim 1, characterized in that: The thickness of the Zr bonding layer is 0.05 to 0.2 μm; The thickness of the ZrN support layer is 0.2 to 0.5 μm; The thickness of the ZrN transition layer is 0.1 to 0.3 μm; The thickness of the ZrCuN composite layer is 0.8-3 μm, and the mass content of Cu in the ZrCuN composite layer is 0.3-10%.

3. The method for preparing the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating according to claim 1 comprises the following steps: Arc ion plating is used to deposit a Zr bonding layer, a ZrN supporting layer and a ZrN transition layer on the substrate surface in sequence; The ZrCuN composite layer is deposited on the surface of the ZrN transition layer by using arc ion plating and high-power pulse magnetron sputtering deposition to obtain the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating.

4. The preparation method according to claim 3, characterized in that: The deposition process conditions of the Zr bonding layer include: the arc target is a Zr target, the target working current is 70 to 150A, the substrate bias is -30 to -150V, the argon gas flow rate is 100 to 500sccm, and the deposition time is 2 to 10min.

5. The preparation method according to claim 3, characterized in that: The deposition process conditions of the ZrN support layer include: the arc target is a Zr target, the target working current is 70 to 150A, the substrate bias is -30 to -150V, the nitrogen flow rate is 400 to 1000sccm, and the deposition time is 10 to 15min.

6. The preparation method according to claim 3, characterized in that: The deposition process conditions of the ZrN transition layer include: the arc target is a Zr target, the target operating current is increased from 80 to 100A to 110 to 160A, the nitrogen flow rate is reduced from 800 to 1000sccm to 200 to 400sccm, the substrate bias is increased from -60 to -90V to -120 to -180V, and the deposition time is 5 to 10min.

7. The preparation method according to claim 3, characterized in that: The deposition process conditions of the ZrCuN composite layer include: the arc target is a Zr target, the sputtering target is a Cu target, the arc target working current is 90-150A, the sputtering target power is 1-5kW, the substrate bias is -80--150V, the nitrogen flow rate is 300-500sccm, and the deposition time is 30-90min.

8. The preparation method according to claim 3, characterized in that: The surface oxide layer of the substrate is removed before use; The substrate comprises titanium alloy, stainless steel, high speed steel or cemented carbide.

9. The preparation method according to claim 8, characterized in that: The removal of the surface oxide layer includes ion etching; the process conditions of the ion etching include: argon gas flow rate of 50 to 150 sccm argon gas, substrate bias voltage of -300 to -600 V, ion source power of 3 to 8 kW, and etching time of 30 to 120 min.

10. Use of the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating according to any one of claims 1 to 2 or the friction-reducing and wear-resistant Zr / ZrN / ZrCuN composite coating prepared by the preparation method according to any one of claims 3 to 9 as a surface protection material.

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