阅读说明：本技术 具有高硬度与高温抗氧化性的Zr-B-N/ZrO2纳米多层复合涂层的制备工艺 (Zr-B-N/ZrO with high hardness and high-temperature oxidation resistance2Preparation process of nano multilayer composite coating ) 是由 王铁钢 张纪福 张浩琪 刘艳梅 阎兵 朱建博 于 2021-08-10 设计创作，主要内容包括：本发明公开了一种具有高硬度与高温抗氧化性的Zr-B-N/ZrO-(2)纳米多层复合涂层的制备工艺,属于涂层技术领域。该工艺是采用高功率脉冲磁控溅射和脉冲直流磁控溅射复合镀膜技术在基体上沉积纳米多层复合涂层,沉积纳米多层复合涂层时：本底真空为5×10～(-3)Pa,沉积压强0.5～0.8Pa；制备Zr-B-N调制层时,Zr靶功率0.4～2.0kw,ZrB-(2)靶功率0.4～1.6kw,偏压为150V,通入Ar以及N-(2)/H-(2)混合气体；制备ZrO-(2)调制层时,开启Zr靶,Zr靶功率0.4～2.0kw,通入Ar和O-(2)；本发明通过工艺设计及优化调制周期和调制比,制备出兼具高硬度、高耐磨性及高耐热能力的涂层。(The invention discloses Zr-B-N/ZrO with high hardness and high-temperature oxidation resistance 2 A preparation process of a nano multilayer composite coating belongs to the technical field of coatings. The process adopts high-power pulse magnetron sputtering and pulse direct current magnetron sputtering composite coating technology to deposit the nano multilayer composite coating on a substrate, and when the nano multilayer composite coating is deposited: background vacuum of 5X 10 ‑3 Pa, the deposition pressure is 0.5-0.8 Pa; when preparing the Zr-B-N modulation layer, the Zr target power is 0.4-2.0 kw, ZrB 2 Target power 0.4-1.6 kw, bias voltage 150V, introducing Ar and N 2 /H 2 Mixing the gas; preparation of ZrO 2 When preparing the layer, starting the Zr target with the power of 0.4-2.0 kw, and introducing Ar and O 2 (ii) a According to the invention, the coating with high hardness, high wear resistance and high heat resistance is prepared by process design and optimization of modulation period and modulation ratio.)

1. Zr-B-N/ZrO with high hardness and high-temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: the process adopts the composite coating technology of high-power pulse magnetron sputtering and pulse direct-current magnetron sputtering to deposit Zr-B-N/ZrO on a substrate₂The target material is selected from metal Zr target and ZrB₂A target; firstly, depositing a metal Zr transition layer on a substrate for 15-25 min, and then depositing Zr-B-N/ZrO₂Nano multilayer composite coatings, deposition of Zr-B-N/ZrO₂When the nano multilayer composite coating is prepared: background vacuum of 5X 10^-3Pa, adjusting the deposition pressure to 0.5-0.8 Pa, and then alternately depositing a Zr-B-N modulation layer and ZrO₂A modulation layer; when preparing Zr-B-N modulation layer, starting Zr target and ZrB₂Target, Zr target power 0.4-2.0 kw, ZrB₂Target power is 0.4-1.6 kw, bias voltage is set to 150V (duty ratio is 50%), Ar and N are introduced₂/H₂Mixing the gas; preparation of ZrO₂When the layer is modulated, keeping the bias voltage at-150V, the deposition pressure at 0.5-0.8 Pa, starting the Zr target with the power of 0.4-2.0 kw, and introducing Ar and O₂(ii) a And setting different target material opening times and gas introduction times according to the thickness of the required modulation layer and the modulation ratio.

2. Zr-B-N/ZrO of claim 1 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: when the Zr-B-N modulation layer is deposited, the flow rate of Ar is introduced to 94sccm, and N is introduced₂/H₂The total flow rate of the mixed gas was 6sccm, N₂/H₂N in the mixed gas₂And H₂The volume ratio of (A) to (B) is 9:1, total gas flow rate of 100 sccm; deposited ZrO₂When the layer is prepared, Ar is introduced at a flow rate of 94sccm and O is introduced₂The flow rate of (2) is 6sccm, and the total flow rate of the gas is 100 sccm.

3. Zr-B-N/ZrO with high hardness and high temperature oxidation resistance according to claim 1 or 2₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: the process specifically comprises the following steps:

(1) fixing the cleaned substrate on a rotary frame in a coating chamber, and pumping the vacuum degree to 3 × 10^-3Pa; zr target connected to high-power pulse magnetron sputtering power supply ZrB₂The target is connected with a pulse direct current magnetron sputtering power supply;

(2) sequentially carrying out glow discharge cleaning and ion bombardment cleaning on the substrate;

(3) depositing a Zr transition layer to improve the bonding strength of the working layer and the substrate;

(4) deposition of Zr-B-N/ZrO₂A nano-multilayer composite coating.

4. Zr-B-N/ZrO of claim 3 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: step (ii) of(2) The glow discharge cleaning process comprises the following steps: and heating the furnace chamber to 300 ℃, introducing 150-200 sccm of argon, setting pulse bias voltage of-800V, and performing glow cleaning on the substrate for 15-20 min.

5. Zr-B-N/ZrO of claim 3 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: in the step (2), the ion bombardment cleaning process comprises the following steps: after glow discharge cleaning, starting Zr and ZrB₂Target, then Zr and ZrB₂The target power is 0.4-2.0 kw and 0.4-1.6 kw respectively, the argon flow is kept at 150-200 sccm, and bombardment cleaning is carried out for 8min under the bias condition of-800V.

6. Zr-B-N/ZrO of claim 3 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: in the step (3), the process of depositing the Zr transition layer is as follows: after glow discharge cleaning and ion bombardment cleaning, setting the bias voltage to be-150V (the duty ratio is 60% -90%), starting the Zr target, setting the power of the Zr target to be 0.4-2.0 kw, introducing 100sccm of argon gas flow, adjusting the deposition pressure to be 0.5-0.8 Pa, and depositing the Zr transition layer for 15-25 min.

7. Zr-B-N/ZrO of claim 1 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: the substrate is metal or hard alloy (hard alloy substrate, stainless steel sheet or silicon chip), and the purity of the target material is 99.9 wt.%.

8. Zr-B-N/ZrO of claim 1 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: prepared Zr-B-N/ZrO₂The nano multilayer composite coating is formed by a Zr-B-N modulation layer and ZrO₂The modulation layers are alternately superposed, the modulation period of the coating is 65-110nm, and the cycle number is more than or equal to 8; the Zr-B-N modulation layer and ZrO₂The modulation ratio of the modulation layer is 1: 1-9: 1.

9. Zr-B-N/ZrO of claim 1 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: the Zr-B-N/ZrO₂The nano multilayer composite coating comprises ZrN nano crystalline phase and ZrO₂A nano composite structure of a nano crystalline phase and a BN amorphous phase, wherein the ZrN phase preferentially grows along a crystal face of a (111) crystal face, and ZrO is formed₂The phase preferentially grows along the (111) and (002) crystal planes.

10. Zr-B-N/ZrO of claim 1 having high hardness and high temperature oxidation resistance₂The preparation process of the nano multilayer composite coating is characterized by comprising the following steps: the Zr-B-N/ZrO₂The hardness of the nano multilayer composite coating is higher than 25GPa, the elastic modulus of the coating is stabilized at 270-350 GPa, and the H/E of the coating can reach 0.096 at most.

Technical Field

The invention relates to the technical field of coatings, in particular to Zr-B-N/ZrO with high hardness and high-temperature oxidation resistance₂A preparation process of a nano multilayer composite coating.

Background

The nano multilayer coating has attracted extensive attention due to special physical and chemical properties, and properties related to the surface of a material, such as hardness, high temperature resistance, oxidation resistance, friction resistance, corrosion resistance and the like, are hot spots of research of people at present. The nano multilayer coating is a multilayer coating with a periodic structure formed by alternately depositing two or more different materials in a nano scale. The nano multilayer coating is mainly divided into metal/metal, metal/nitride (carbide, boride), nitride (carbide, boride)/nitride (carbide, boride) and the like, and the nano multilayer coating with high mechanical property is obtained by controlling the modulation period and modulation ratio of the multilayer film.

ZrB₂The coating has the characteristics of high melting point, high hardness, good heat conductivity and the like, but ZrB₂The brittleness is large, the sudden failure is easy to happen, and the popularization and the application of the material are limited. In ZrB₂N element is doped in the Zr-B-N coating, the mechanical property of the Zr-B-N coating under different process parameters is researched, the film has a nano composite structure of amorphous a-BN coated nano crystal nc-ZrN, the content of the N element in the Zr-B-N coating is increased, and the hardness is higher than that of the Zr-B₂The toughness is greatly improved while the toughness is reduced. In order to improve the heat resistance and the oxidation resistance of the Zr-B-N coating, a series of Zr-B-O-N coatings with different O contents are subsequently prepared, wherein the Zr-B-O-N coatings are prepared from a- (BN, B)₂O₃) Wrapping nc- (ZrO)₂，Zr₃N₄) The highest hardness of the nano composite structure composition is reduced to 16.11GPa although the oxidation resistance is improved.

Disclosure of Invention

In order to further improve the oxidation resistance of the prior Zr-B-N coating and the hardness of the Zr-B-O-N coating, the invention aims to provide a Zr-B-N/ZrO coating with high hardness and high-temperature oxidation resistance₂The preparation process of the nanometer multilayer composite coating adopts the pulse direct current and high-power pulse composite magnetron sputtering technology to mix Zr-B-N and ZrO₂The two materials are alternately deposited, and Zr-B-N/ZrO with high hardness, high wear resistance and high heat resistance is prepared by process design and optimization of film thickness proportion and modulation ratio of the modulation layer₂A nano-multilayer composite coating.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

Zr-B-N/ZrO with high hardness and high-temperature oxidation resistance₂The preparation process of the nanometer multilayer composite coating is to deposit Zr-B-N/ZrO on a substrate by adopting a high-power pulse magnetron sputtering and pulse direct-current magnetron sputtering composite coating technology₂The target material is selected from metal Zr target and ZrB₂A target; firstly, depositing a metal Zr transition layer for 20min on a substrate, and then depositing Zr-B-N/ZrO₂Nano multilayer composite coatings, deposition of Zr-B-N/ZrO₂When the nano multilayer composite coating is prepared: background vacuum of 5X 10^-3Pa, adjusting the deposition pressure to 0.5-0.8 Pa, and then alternately depositing a Zr-B-N modulation layer and ZrO₂A modulation layer; when preparing Zr-B-N modulation layer, starting Zr target and ZrB₂Target, Zr target power 0.4-2.0 kw (preferably 1.1-1.3 kw), ZrB₂Target power is 0.4-1.6 kw (preferably 0.7-0.9 kw), bias voltage is set to 150V (duty ratio 50%), Ar and N are introduced₂/H₂Mixing the gas; preparation of ZrO₂When preparing the layer, keeping the bias voltage at-150V, depositing the layer with the pressure of 0.5-0.8 Pa (preferably 0.55-0.65 kw), only starting the Zr target with the power of 0.4-2.0 kw (preferably 1.1-1.3 kw), and introducing Ar and O₂(ii) a And setting different target material opening times and gas introduction times according to the thickness of the required modulation layer and the modulation ratio.

When the Zr-B-N modulation layer is deposited, the flow rate of Ar is introduced to 94sccm, and N is introduced₂/H₂The total flow rate of the mixed gas was 6sccm, N₂/H₂N in the mixed gas₂And H₂The volume ratio of (A) to (B) is 9:1, total gas flow rate of 100 sccm; deposited ZrO₂When the layer is prepared, Ar is introduced at a flow rate of 94sccm and O is introduced₂The flow rate of (2) is 6sccm, and the total flow rate of the gas is 100 sccm.

The Zr-B-N/ZrO with high hardness and high-temperature oxidation resistance₂Nano-multilayerThe preparation process of the composite coating specifically comprises the following steps:

(1) fixing the cleaned substrate on a rotary frame in a coating chamber, and pumping the vacuum degree to 3 × 10^-3Pa; zr target connected to high-power pulse magnetron sputtering power supply ZrB₂The target is connected with a pulse direct current magnetron sputtering power supply; the substrate is metal or hard alloy (hard alloy substrate, stainless steel sheet or silicon chip), and the purity of the target material is 99.9 wt.%.

(2) Sequentially carrying out glow discharge cleaning and ion bombardment cleaning on the substrate; the glow discharge cleaning process comprises the following steps: heating the furnace chamber to 300 ℃, introducing 150-200 sccm of argon, setting pulse bias voltage to-800V, and performing glow cleaning on the substrate for 15-20 min; the ion bombardment cleaning process comprises the following steps: after glow discharge cleaning, starting Zr and ZrB₂Target, then Zr and ZrB₂The target power is 0.4-2.0 kw (preferably 0.9-1.1 kw) and 0.4-1.6 kw (preferably 0.7-0.9 kw), the argon flow is kept at 150-200 sccm, and the bombardment cleaning is carried out for 8min under the bias condition of-800V.

(3) Depositing a Zr transition layer to improve the bonding strength of the working layer and the substrate, wherein the process of depositing the Zr transition layer is as follows: after glow discharge cleaning and ion bombardment cleaning, setting the bias voltage to be-150V (the duty ratio is 60% -90%), starting the Zr target, setting the power of the Zr target to be 0.4-2.0 kw (preferably 1.1-1.3 kw), introducing argon gas flow to be 100sccm, adjusting the deposition pressure to be 0.5-0.8 Pa, and depositing the Zr transition layer for 15-25 min.

(4) Deposition of Zr-B-N/ZrO₂A nano-multilayer composite coating.

Zr-B-N/ZrO prepared by the invention₂The nano multilayer composite coating is formed by a Zr-B-N modulation layer and ZrO₂The modulation layers are alternately superposed, the modulation period of the coating is 65-110nm, and the cycle number is more than or equal to 8; the Zr-B-N modulation layer and ZrO₂The modulation ratio of the modulation layer is 1: 1-9: 1, preferably 4: 1-8: 1.

the Zr-B-N/ZrO₂The nano multilayer composite coating comprises ZrN nano crystalline phase and ZrO₂A nano composite structure of a nano crystalline phase and a BN amorphous phase, wherein the ZrN phase preferentially grows along a crystal face of a (111) crystal face, and ZrO is formed₂Preferred growth of phase edges (111) and (002) crystal planesLong.

The Zr-B-N/ZrO₂The hardness of the nano multilayer composite coating is higher than 25GPa, the elastic modulus of the coating is stabilized at about 270-350 GPa, and the highest H/E of the coating can reach 0.096.

The design mechanism of the invention is as follows:

the invention adopts the pulse direct current and high power pulse composite magnetron sputtering technology to deposit Zr-B-N/ZrO on the hard alloy sheet, SUS304 stainless steel and single crystal Si sheet₂A nano-multilayer composite coating.

By carrying out HiPIMS, pulse direct current magnetron sputtering and direct current magnetron sputtering ZrB₂Comparative studies of coating properties, which are known to have lower fracture toughness, hinder ZrB₂The coating is used as a wear resistant coating, so the toughness is improved by improving ZrB₂An effective method with promising coating application prospect. BN has low binding energy, easily forms a short-range ordered amorphous structure, and amorphous substances have low hardness and good plasticity. The amorphous coated crystals exist in the coating to form a nano composite structure, namely, the gaps of the crystals are filled with the amorphous, which compensates the ZrB₂The coating has the defects of high hardness and high fracture brittleness, and the high-temperature thermal stability of the coating is improved. Furthermore, the ZrO coating₂Has the advantages of high temperature resistance, chemical corrosion resistance, oxidation resistance, wear resistance, good toughness, low thermal conductivity, low friction coefficient and the like. By periodic implantation of ZrO in Zr-B-N coatings₂The oxidation resistance of the coating is greatly improved on the premise of not obviously reducing the mechanical property and the tribological property of the Zr-B-N coating by designing process conditions and optimizing the modulation period and the modulation ratio. Modulation layer ZrO₂Can effectively prevent the interior of the coating from being further oxidized, and has good thermal barrier and chemical barrier functions. Prepared Zr-B-N/ZrO₂The nano multilayer composite coating has a large number of interfaces, the performances of all aspects of the nano multilayer composite coating are obviously different from those of a single-layer coating, and the prepared multilayer coating can improve the toughness and the high-temperature oxidation resistance of a cutter.

The invention has the following advantages and beneficial effects:

1. Zr-B-N/ZrO prepared by the invention₂The nano multilayer composite coating has high oxidation resistanceHas obvious high temperature resistant effect.

2. Zr-B-N/ZrO of the invention₂The nano multilayer composite coating is a nano composite structure formed by inlaying ZrN nanocrystals in a BN amorphous layer and ZrO₂The multilayer composite coating formed by the nanometer modulation layer has the advantages of high hardness, good wear resistance, stable chemical performance and the like.

3. Zr-B-N/ZrO of the invention₂The nano multilayer composite coating has wide application prospect, is suitable for high-speed dry cutting of various difficult-to-process materials, greatly improves the cutting efficiency and prolongs the service life of a cutter.

4. Zr-B-N/ZrO of the invention₂The nano multilayer composite coating has excellent high-temperature oxidation resistance and good mechanical property and frictional wear property, and the coated cutter can be suitable for heavy-load intermittent machining.

Drawings

FIG. 1 shows Zr-B-N/ZrO prepared by pulse direct current and high power pulse composite magnetron sputtering technology in example 1 at different modulation ratios₂The surface appearance and the cross section appearance of the nano multilayer composite coating.

FIG. 2 is a diagram of Zr-B-N/ZrO prepared by the pulse direct current and high power pulse composite magnetron sputtering technology in example 1₂XRD pattern of nano multilayer composite coating.

FIG. 3 shows Zr-B-N/ZrO prepared by the pulse direct current and high power pulse composite magnetron sputtering technology in example 1 at different modulation ratios₂Hardness and modulus of elasticity of the nano-multilayer composite coating.

FIG. 4 shows Zr-B-N/ZrO prepared by the pulse direct current and high power pulse composite magnetron sputtering technology in example 1 at different modulation ratios₂Scratch morphology of the nano multilayer composite coating.

FIG. 5 shows Zr-B-N/ZrO prepared by the pulse direct current and high power pulse composite magnetron sputtering technology in example 1 at different modulation ratios₂Coefficient of friction of the nano-multilayer composite coating.

FIG. 6 shows Zr-B-N/ZrO prepared by the pulse direct current and high power pulse composite magnetron sputtering technology in example 1 at different modulation ratios₂The appearance of grinding marks of the nano multilayer composite coating.

FIG. 7 shows Zr-B-N/ZrO at different modulation periods in example 2₂The surface appearance and the cross section appearance of the nano multilayer composite coating.

FIG. 8 shows Zr-B-N/ZrO in example 2₂XRD pattern of nano multilayer composite coating.

FIG. 9 shows Zr-B-N/ZrO at different modulation periods in example 2₂Hardness and modulus of elasticity of the nano-multilayer composite coating.

FIG. 10 shows Zr-B-N/ZrO at different modulation periods in example 2₂Scratch morphology of the nano multilayer composite coating.

FIG. 11 shows Zr-B-N/ZrO at different modulation periods in example 2₂Coefficient of friction of the nano-multilayer composite coating.

FIG. 12 shows Zr-B-N/ZrO at different modulation periods in example 2₂The appearance of grinding marks of the nano multilayer composite coating.

Detailed Description

The present invention will be described in further detail by way of examples.

Example 1:

this example is to prepare Zr-B-N/ZrO with a modulation period of 80nm and different modulation ratios₂A nano-multilayer composite coating.

In this example, Zr-B-N/ZrO was deposited on a single crystal Si sheet (40 mm. times.40 mm. times.0.67 mm), a cemented carbide sheet (25 mm. times.25 mm. times.3.0 mm) and a stainless steel sheet (35 mm. times.35 mm. times.1.0 mm)₂The nanometer multilayer composite coating is coated by adopting a pulse direct current and high-power pulse composite magnetron sputtering technology. The specific operation steps are as follows:

(1) polishing the hard alloy substrate, placing the polished hard alloy substrate and a prepared monocrystalline silicon wafer and 304 stainless steel sheet in an ultrasonic cleaning machine, sequentially ultrasonically cleaning in acetone and alcohol solution for 20min, and then using high-purity N₂(99.999 percent), drying, pressing at the designated position of a clamp, opening the furnace door of the vacuum chamber after the vacuum chamber is vacuumized, fixing the substrate on a rotating frame in a coating chamber by using an iron wire, and then, fixing the metal Zr target and the ZrB target₂The targets are uniformly arranged on the inner wall of the furnace body of the magnetron sputtering equipment; adjusting the fixed position of the substrate to make the substrate face the surface of the target material, and preventing the deposition distance on the surface in the deposition processAnd different, the phenomenon of nonuniform coating preparation is caused. Adjusting the position of the clamp, checking whether foreign matters remain in the vacuum chamber, and closing the furnace door.

(2) Vacuumizing: the molecular pump can not work when the pressure in the vacuum chamber is higher than 4.0Pa, so the vacuum pumping is divided into two steps. Firstly, starting to vacuumize under atmospheric pressure, utilizing TRP-90 type rough pump to vacuumize vacuum chamber, when the vacuum degree in the vacuum chamber reaches 4.0Pa, opening molecular pump to accelerate the molecular pump, when the vacuum degree reaches 3.0Pa, opening IP2200 type molecular pump (the air extraction speed is more than or equal to 1600L/s) valve, further vacuumizing until the pressure in the vacuum chamber reaches 5 x 10^-3And (4) below Pa, starting a heating source to heat the vacuum chamber, setting the final temperature to be 400 ℃, setting the alarm temperature to be 450 ℃, and keeping the rotating frame to rotate forwards for 40Hz in the heating process to ensure that the substrate is uniformly heated. Until the temperature stabilized at 400 ℃ and the vacuum reached 3X 10^-3Pa。

(3) Glow discharge cleaning of the vacuum chamber: pumping the background vacuum degree of the vacuum chamber to 3.0 x 10^-3Heating to 300 ℃ after Pa, then applying-800V bias voltage with the bias voltage duty ratio of 87%, introducing Ar (99.999%) into the vacuum chamber, controlling the flow of Ar to be 200sccm, adjusting the throttle valve to keep the working pressure at 1.5Pa, and performing glow discharge cleaning for 15 min;

(4) bombarding and cleaning the surface of the target material: keeping the flow of Ar at 200sccm, and starting the Zr target and the ZrB₂A target provided with Zr and ZrB₂The target power is 1kw and 0.8kw, the pulse bias voltage is-800V, the bias voltage duty ratio is 87%, the working pressure is maintained at 0.8Pa, and the target material bombardment time is 8 min. And removing the pollution layer and the oxide on the surfaces of the substrate and the target.

(5) When the transition layer is deposited, Ar (99.999%) is introduced, the gas flow is 100sccm, the Zr target is started, the power is 1.2kw, the pulse bias voltage is-150V, the bias voltage duty ratio is 70%, the working pressure is maintained at 0.8Pa, and the time is 20 min.

(6) When preparing the Zr-B-N modulation layer, the bias voltage is reduced to-150V, the bias voltage duty ratio is 50 percent, Ar is introduced, the flow rate is 94sccm, and N is adjusted₂+H₂Flow rate of the mixture was 6sccm (N)₂Is 5.4sccm, H₂0.6sccm), the total flow rate was maintained at 100sccm, and the Zr target and ZrB were turned on₂Target, power 1.2kw and 08kw, maintaining the working pressure at 0.6Pa by adjusting the throttle valve; preparation of ZrO₂When the layer is modulated, the bias voltage is kept at-150V, the bias voltage duty ratio is kept at 50%, the Ar flow is 94sccm, and O is adjusted₂The flow rate is 6sccm, the power of the opened Zr target is set to be 1.2kw, and the working pressure is kept at 0.6 Pa. Depositing ZrO during the periodic preparation of the modulation layer₂Closing the target material after preparing the layer, and introducing 30s of reducing gas H₂Oxygen in the vacuum chamber is fully reduced, and oxygen impurities are prevented from being doped in the Zr-B-N modulation layer. Zr-B-N/ZrO₂The total number of the layers of the nano multilayer composite coating is adjusted to 20.

Zr-B-N/ZrO at different modulation ratios prepared in this example₂The nano multilayer composite coating is subjected to morphology characterization and performance test, and specifically comprises the following steps:

the phase composition of the coating is analyzed by an X-ray diffractometer (XRD), data are collected in a step scanning mode, incident X-rays are radiated by a Cu target Ka characteristic spectral line (lambda is 0.154056nm), the tube voltage is 40kV, the tube current is 40mA, the scanning range of a diffraction angle (2 theta) is 20-80 degrees, the scanning step is 0.02 degree, and the counting time of each step is 0.2 s. The surface and cross-sectional morphology of the coating was observed using a field emission Scanning Electron Microscope (SEM) model S4800, and the chemical composition of the coating was analyzed using an electron probe (EPMA, Shimadzu, EPMA 1600). The hardness and the elastic modulus of the coating are tested by adopting a nano indenter (Anton Paar, TTX-NHT-3), in order to eliminate the influence of the matrix effect on the measurement result, the pressing depth of the needle point is ensured not to exceed 1/10 of the thickness of the coating, and the average value is taken from 15 points. The bonding strength of the coating to the SUS304 stainless steel substrate was measured using a scratch tester (Anton Paar RST-3) with a diamond tip diameter of 200 μm and the following parameters: the loading speed is 6 mm/min; the scratch length is 3 mm; the load 50N is set and the experimental data is recorded by the computer in real time.

The friction coefficient was measured on a friction and wear tester (Anton Paar THT) using 5.99mm diameter Al for the friction pair₂O₃The ball (hardness 22 + -1 GPa), sliding linear velocity 0.1m/s, normal load 2N, rotation radius 6mm, and sliding distance 100 m. The rubbing test was carried out at room temperature 22 ± 3 ℃ and humidity 30%, each sample piece was tested 3 times, and the coating wear rate W was calculated using the formula W ═ V/(F × S) (V is wear volume,f is normal load and S is sliding distance), and the profile of the coating after abrasion was observed using a super depth of field microscope (VHX-1000C, Keyence).

FIG. 1 shows Zr-B-N/ZrO at different modulation ratios₂The surface appearance and the cross section appearance of the nano multilayer composite coating. According to SEM images, the nano multilayer composite coating presents obvious periodic modulation microstructures and has relatively straight and clear modulation layer interfaces. The substrate in the figure is produced by the difference of average electron density of adjacent modulation layers, wherein the light stripes are ZrO₂Layer, dark stripe is a Zr-B-N layer. The coating is observed in an enlarged way, and a large and small dark spot area exists, the special structure in the Zr-B-N modulation layer is an 'amorphous phase wrapped crystal phase' structure, and the amorphous BN area is wrapped by the nano-crystal. The lattice stripes of the nano multilayer coating pass through a plurality of modulation layer interfaces and are kept continuous, which shows that ZrO is in a certain degree₂Coherent epitaxy occurs under the action of a Zr-B-N template, and the existence of the phenomenon can greatly improve the hardness of the coating.

FIG. 2 shows Zr-B-N/ZrO₂XRD pattern of nano multilayer composite coating. Zr-B-N/ZrO₂ZrO with nano multilayer composite coating having preferential growth orientation on (111) crystal face₂And a ZrN crystal phase, where the diffraction peak of the multilayer film is not shifted but the intensity is significantly improved, indicating that Zr-B-N/ZrO₂The crystallinity of the nano-multilayer composite coating is improved. ZrO grown along (311) crystal plane at 2 theta-60.986 DEG position₂The phase diffraction peak intensity is enhanced.

FIG. 3 is a graph showing the Zr-B-N/ZrO testing at different modulation ratios by using a nanoindenter₂Nano-hardness and elastic modulus of the nano-multilayer composite coating. Modulation ratio (Zr-B-N layer to ZrO)₂Thickness ratio of layers) is 1: 1. 3: 1. 5: 1. 9:1, the nano-multilayer composite coating hardness is floated between 25.6 +/-1 GPa, and when the modulation ratio is 7: 1, the maximum hardness of the nano multilayer composite coating is 30.18 GPa. The hardness of the single-layer Zr-B-N nano multi-layer composite coating prepared under the same parameters is 23.22GPa, and is improved by 29.8%; single layer ZrO₂The hardness of the coating is 24.21GPa, and the hardness is improved by 24.7 percent. The nano multilayer composite coating is modulated at the modulation period of 80nmThe ratio is 5: the elastic modulus at 1 is 305.12GPa at the minimum.

FIG. 4 shows Zr-B-N/ZrO at different modulation ratios₂And (4) the appearance of the nano multilayer composite coating after scratch test. The membrane/base binding force tends to increase first and then decrease and finally increase greatly as the modulation ratio increases. The presence of appropriate compressive stress increases the fracture toughness of the film, adjusted to a ratio of 5: the membrane/base binding force at 1 is 43.99N at the most. Adjusting the ratio to be 1: 1, the content of oxide in the film is higher, and the brittleness is larger, and the ratio is adjusted to 9:1, the internal stress of the film is overlarge, the H/E value is lower, the toughness is poorer, and the film/base binding force is reduced.

FIG. 5 shows Zr-B-N/ZrO at different modulation ratios₂And the friction coefficient of the coating of the nano multilayer composite coating is tested by friction and wear. A tendency of decreasing first and then increasing is exhibited, and at a modulation ratio of 5: 1 is 0.838 minimum. The modulation ratio is 1: 1 and 5: 1, it can be seen that a large amount of abrasive dust exists in the grinding marks, the abrasive dust peeled off in the friction process participates in friction in the friction test, and the friction coefficient is increased, and 5: 1 and 7: the film of 1 has less grinding chips in grinding trace appearance and lower friction coefficient.

FIG. 6 shows Zr-B-N/ZrO at different modulation ratios₂The appearance of grinding marks of the nano multilayer composite coating. When the modulation ratio is 5: 1 and 7: 1, relatively narrow wear scar and less surface abrasive dust, and an inverse modulation ratio of 1: 1. 3: 1 and 9:1, the film has a deep grinding mark shape, the grinding mark is dark in color and is in a furrow shape, a large amount of grinding dust is accumulated in the grinding mark, and the grinding dust at the edge of the grinding mark is also large.

Example 2:

this example is to prepare the modulation ratio (Zr-B-N layer and ZrO)₂Layer thickness ratio) of 5: 1. Zr-B-N/ZrO with different modulation periods (40, 60, 80, 100, 120nm)₂A nano-multilayer composite coating.

This example is the deposition of Zr-B-N/ZrO with different modulation periods on mirror polished single crystal Si wafers ((100) facets) and cemented carbide₂The nano multilayer composite coating has the substrate size of 50mm multiplied by 10mm multiplied by 0.7 mm. Before coating, the substrate is ultrasonically cleaned in alcohol solution for 20 minutes, then is dried by high-purity nitrogen, and is placed on a sample rack in a vacuum chamber opposite to the target. Coating filmThe process is carried out on a V-TECH AS610 type high-power pulse and pulse direct-current composite magnetron sputtering coating machine, an arc ion plating cathode is also arranged on the coating machine, and the target material is respectively selected from a metal Zr target and a compound ZrB₂Target (purity is wt.99.9%), high-purity Ar (purity is 99.999%) and high-purity O are respectively selected as working gas and reaction gas₂(purity 99.999%) N₂+H₂Mixed gas (gas volume ratio 9:1)

The specific process is as follows: metal Zr target and ZrB₂The targets are uniformly arranged on the inner wall of the furnace body of the magnetron sputtering equipment, and the background vacuum degree of the vacuum chamber is pumped to 3.0 multiplied by 10^-3Pa, heating to 300 ℃, then applying-800V bias voltage with the bias voltage duty ratio of 87%, introducing Ar (99.999%) into the vacuum chamber, controlling the gas flow to be 200sccm, adjusting the throttle valve to keep the working pressure at 1.5Pa, and performing glow discharge cleaning for 15 min: regulating Ar gas flow to 100sccm, changing pressure in the vacuum chamber, regulating throttle valve angle to stabilize pressure in the vacuum chamber at 0.6Pa, maintaining substrate bias and duty ratio parameters, and regulating Zr and ZrB₂The target power is 1kw and 0.8kw respectively, so that the surface of the target material is uniformly bombarded and cleaned, impurities are fully removed, and the target is maintained for 8 min. And removing the pollution layer and the oxide on the surfaces of the substrate and the target. When the transition layer is deposited, Ar (99.999%) is introduced, the gas flow is 100sccm, the Zr target is started, the power is 1.2kw, the pulse bias voltage is-150V, the bias voltage duty ratio is 70%, the working pressure is maintained at 0.8Pa, and the time is 20 min. When preparing the Zr-B-N modulation layer, the bias voltage is reduced to-150V, the bias voltage duty ratio is 50 percent, Ar is introduced, the flow rate is 94sccm, and N is adjusted₂+H₂The flow rate was 6(5.4+0.6) sccm, the total flow rate was maintained at 100sccm, and the Zr target and ZrB were turned on₂The target has power of 1.2kw and 0.8kw respectively, and the working pressure is kept at 0.6Pa by adjusting the throttle valve; preparation of ZrO₂When the layer is modulated, the bias voltage is kept at-150V, the bias voltage duty ratio is kept at 50%, the Ar flow is 94sccm, and O is adjusted₂The flow rate is 6sccm, the power of the opened Zr target is set to be 1.2kw, and the working pressure is kept at 0.6 Pa. Depositing ZrO during the periodic preparation of the modulation layer₂Closing the target material after preparing the layer, and introducing 30s of reducing gas H₂Oxygen in the vacuum chamber is fully reduced, and oxygen impurities are prevented from being doped in the Zr-B-N modulation layer.

FIG. 7 shows Zr-B-N/ZrO at different modulation periods₂The surface appearance and the cross section appearance of the nano multilayer composite coating. According to SEM images, the nano multilayer composite coating presents obvious periodic modulation microstructures and has relatively straight and clear modulation layer interfaces. The substrate in the figure is produced by the difference of average electron density of adjacent modulation layers, wherein the light stripes are ZrO₂The layer, dark stripe is a Zr-B-N layer, presents a glassy microstructure with no characteristics of non-columnar crystals, and the coating surface is compact and has very fine grains. No pinholes and pores were observed in the cross-sectional morphology, N₂The growth of the crystal grains is limited, and the amorphous layer wraps the crystal grains with small sizes to form a nano composite structure.

FIG. 8 shows Zr-B-N/ZrO₂XRD pattern of nano multilayer composite coating. Zr-B-N/ZrO₂ZrO with nano multilayer composite coating having preferential growth orientation on (111) crystal face₂And a ZrN crystal phase, where the diffraction peak of the multilayer film is not shifted but the intensity is significantly improved, indicating that Zr-B-N/ZrO₂The crystallinity of the nano-multilayer composite coating is improved. ZrO grown along (311) crystal plane at 2 theta-60.986 DEG position₂The phase diffraction peak intensity is enhanced.

FIG. 9 shows Zr-B-N/ZrO at different modulation periods₂Hardness and modulus of elasticity of the nano-multilayer composite coating. Zr-B-N/ZrO prepared under different modulation periods₂The hardness of the nano multilayer film reaches the maximum value of 24.61GPa when the modulation period is 80nm, the surface roughness of the film is minimum at the moment, and the fine structure of crystal grains between modulation layers is compact and presents a non-columnar crystal nano composite structure. The modulation period is 100nm, the modulation ratio is 5: the modulus of elasticity at 1 was 333.48 GPa. Zr-B-N/ZrO₂ZrO in nano multilayer film₂Phase (aZrO)₂5.3) and a ZrN phase (aZrN 4.57), lattice mismatch may occur at the interface, and coherent distortion may occur, so that the film performance is enhanced.

FIG. 10 shows Zr-B-N/ZrO at different modulation periods₂Scratch morphology of the nano multilayer composite coating. Zr-B-N/ZrO prepared under different adjustment periods₂The nano-multilayer films all exhibit compressive stress. Is adjusted to the period ofThe membrane/substrate binding force at 80nm is 43.99N maximum. When the period is adjusted to 80nm, the maximum H/E value is 0.081, and the membrane/substrate binding force is relatively strong. As can be seen from the scratch morphology, the film had a flaking phenomenon, probably due to the incorporation of brittle phase ZrH in the multilayer film.

FIG. 11 shows Zr-B-N/ZrO at different modulation periods₂Coefficient of friction of the nano-multilayer composite coating. The modulation period is 80nm, and the modulation ratio is 5: the minimum value of 1 is 0.838, and the change trend is consistent with the abrasion topography of the film. The appearance graph of the grinding marks shows that the film has less grinding dust, narrower grinding marks and lower friction coefficient. During the friction and wear test, the film has brittle spalling to participate in friction, so that the friction coefficient is large.

FIG. 12 shows Zr-B-N/ZrO at different modulation periods₂The appearance of grinding marks of the nano multilayer composite coating. The figure shows that the grinding scars are accumulated and are in a furrow shape. When the modulation period is 80nm, the wear scar is relatively narrow and the surface abrasive dust is less.

The invention has been described in an illustrative manner, and it is to be understood that any simple variations, modifications or other equivalent changes which can be made by one skilled in the art without departing from the spirit of the invention fall within the scope of the invention.