阅读说明：本技术 一种三维网状纳米晶/非晶的高强高韧纳米多层膜及其制备方法和应用 (Three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film and preparation method and application thereof ) 是由 文懋 齐金磊 王龙鹏 郝俊 张侃 郑伟涛 于 2020-07-15 设计创作，主要内容包括：本发明涉及航空材料技术领域,具体涉及一种三维网状纳米晶/非晶的高强高韧纳米多层膜及其制备方法和应用。本发明提供的三维网状纳米晶/非晶的高强高韧纳米多层膜,包括交替叠加设置的合金金属氮化物层和纯金属氮化物层；所述合金金属氮化物层和纯金属氮化物层均具有纳米晶和非晶共存结构；以依次叠层设置的一层合金金属氮化物层和一层纯金属氮化物层为一个单元。在本发明中,合金金属氮化物层和纯金属氮化物层均具有纳米晶和非晶共存结构,在沉积多个单元的过程中,使得在一个或多个单元内同时存在多个调制层共格的纳米晶相区域和非晶相区域,由纳米晶和非晶的界面形成空间的三维网状结构,提高了膜层的硬度和韧性。(The invention relates to the technical field of aviation materials, in particular to a three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, and a preparation method and application thereof. The three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film provided by the invention comprises an alloy metal nitride layer and a pure metal nitride layer which are alternately overlapped; the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure; a layer of alloy metal nitride layer and a layer of pure metal nitride layer which are sequentially laminated are taken as a unit. In the invention, the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure, so that a nanocrystalline phase region and an amorphous phase region which are coincided with each other by a plurality of modulation layers exist in one or more units simultaneously in the process of depositing a plurality of units, and a spatial three-dimensional network structure is formed by the interface of the nanocrystalline and the amorphous, thereby improving the hardness and the toughness of the film layer.)

1. A three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film comprises an alloy metal nitride layer and a pure metal nitride layer which are alternately overlapped, wherein the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure; the method comprises the following steps that a layer of alloy metal nitride layer and a layer of pure metal nitride layer which are sequentially stacked are taken as a unit, a plurality of nanocrystalline phase areas and amorphous phase areas exist in one unit or a plurality of units at the same time, and a space three-dimensional network structure is formed by the interfaces of the nanocrystalline phase areas and the amorphous phase areas.

2. The high-strength high-toughness nano multilayer film as claimed in claim 1, wherein the number of the units of the high-strength high-toughness nano multilayer film is 40-100; the thickness ratio of the alloy metal nitride layer to the pure metal nitride layer in each unit is 10: 1-12 independently.

3. The high strength high toughness nano multilayer film according to claim 1 or 2, wherein the alloy metal nitride layer is Ti₂AlNbN thin film, Ti₃AlN thin film or Ti₂An AlTaN film; the pure metal nitride layer is Zr₃N₄Film, Hf₃N₄Film or Ti₂And (6) N thin films.

4. The preparation method of the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film as claimed in any one of claims 1 to 3, which comprises the following steps:

argon is used as sputtering gas, nitrogen is used as reaction gas, magnetron sputtering technology is adopted, and alloy metal targets and pure metal targets are used as sputtering targets to respectively and alternately sputter the substrate, so that the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film is obtained.

5. The method of claim 4 wherein the vacuum chamber is maintained at a vacuum level of greater than 4 x 10 prior to sputtering^-4Pa; the working pressure in the sputtering process is 0.5-1.2 Pa.

6. The preparation method according to claim 4, wherein in the sputtering process, the surface of the substrate is parallel to the surface of the sputtering target, the base distance between the substrate and the sputtering target is 8-12 cm, and the bias voltage is-80V to-120V.

7. The production method according to claim 4, wherein the sputtering current of the alloy metal target is 0.2 to 0.6A; the sputtering current of the pure metal target is 0.3-0.7A;

the deposition rate of the alloy metal target is 15-20 nm/min; the deposition rate of the pure metal target is 9-15 nm/min.

8. The production method according to claim 4, wherein the substrate is previously cleaned and dried before the sputtering is performed.

9. The method according to claim 4, further comprising, after the sputtering is completed: and cooling the obtained film to room temperature under a vacuum condition to obtain the three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film.

10. The three-dimensional meshed nano-crystalline/amorphous high-strength high-toughness nano-multilayer film as described in any one of claims 1 to 3 or the three-dimensional meshed nano-crystalline/amorphous high-strength high-toughness nano-multilayer film prepared by the preparation method as described in any one of claims 4 to 9 is applied as a blade protective coating.

Technical Field

The invention relates to the technical field of aviation materials, in particular to a three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, and a preparation method and application thereof.

Background

The aeroengine industry determines national defense strength of a country and the overall competitiveness of the aeroengine industry, and the gas compressor can improve the pressure of air entering a combustion chamber, so that the gas working efficiency is higher, a higher thrust-weight ratio is obtained, and the aeroengine is one of core components of the aeroengine. The high thrust-weight ratio engine has the advantages that the blades of the air compressor of the engine are subjected to erosion of sand, stones and the like in the air and environmental corrosion due to the ultrahigh rotating speed of the engine, the shape, the size and the surface smoothness of the blades are changed, the performance of the engine is reduced structurally and aerodynamically, the oil consumption is increased, and the service life of the engine is greatly shortened, so that the development of a high-strength high-toughness erosion-resistant protective coating is the most effective means for prolonging the service life of the blades of the air compressor and ensuring the safe operation of the engine, and the wide attention is paid at home and abroad.

The traditional hard coating material mainly comprises a hard single-layer film, the high strength of the traditional hard coating material is usually maintained at the cost of ductility, and the research on the toughness of the coating while ensuring the high hardness is an urgent requirement of various engineering applications. Due to the rise of nanotechnology, a large number of methods are used for hardening and toughening hard materials, wherein the intrinsic mode is to optimize an electronic structure on the atomic scale to realize the improvement of performance by adding component modulation or doping soft and hard phase element particles in a coating. In an external toughening (hard) mode, the nano multilayer film can deflect and passivate cracks and prevent dislocation generation and movement by introducing two crystalline films or one crystalline film or one amorphous film into an interlayer interface of the nano multilayer film, and the nano multilayer film is constructed to be an effective means for hardening and toughening due to the advantages of multifunctional combination, better hardness/toughness ratio and the like.

Although the nano multilayer film constructed at present has achieved remarkable results, the requirements of mechanical parts for adapting to severe conditions are continuously increased, and higher requirements are provided for hardening and toughening of materials.

Disclosure of Invention

The invention aims to provide a three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film, and a preparation method and application thereof.

In order to achieve the above object, the present invention provides the following technical solutions:

the invention provides a three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, which comprises an alloy metal nitride layer and a pure metal nitride layer which are alternately overlapped, wherein the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure; the method comprises the following steps that a layer of alloy metal nitride layer and a layer of pure metal nitride layer which are sequentially stacked are taken as a unit, a plurality of nanocrystalline phase areas and amorphous phase areas exist in one unit or a plurality of units at the same time, and a space three-dimensional network structure is formed by the interfaces of the nanocrystalline phase areas and the amorphous phase areas.

Preferably, the number of the units of the high-strength high-toughness nano multilayer film is 40-100; the thickness ratio of the alloy metal nitride layer to the pure metal nitride layer in each unit is 10: 1-12 independently.

Preferably, the alloy metal nitride layer is Ti₂AlNbN thin film, Ti₃AlN thin film or Ti₂An AlTaN film; the pure metal nitride layer is Zr₃N₄Film, Hf₃N₄Film or Ti₂And (6) N thin films.

The invention also provides a preparation method of the three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, which comprises the following steps:

argon is used as sputtering gas, nitrogen is used as reaction gas, magnetron sputtering technology is adopted, and alloy metal targets and pure metal targets are used as sputtering targets to respectively and alternately sputter the substrate, so that the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film is obtained.

Preferably, the sputtering is carried out, prior to,the vacuum degree of the vacuum coating chamber is better than 4 multiplied by 10^-4Pa; the working pressure in the sputtering process is 0.5-1.2 Pa.

Preferably, in the sputtering process, the surface of the substrate is parallel to the surface of the sputtering target, the target base distance between the substrate and the sputtering target is 8-12 cm, and the bias voltage is-80 to-120V.

Preferably, the sputtering current of the alloy metal target is 0.2-0.6A; the sputtering current of the pure metal target is 0.3-0.7A;

the deposition rate of the alloy metal target is 15-20 nm/min; the deposition rate of the pure metal target is 9-15 nm/min.

Preferably, the substrate is previously cleaned and dried before the sputtering is performed.

Preferably, after the sputtering is finished, the method further includes: and cooling the obtained film to room temperature under a vacuum condition to obtain the three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film.

The invention also provides an application of the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film prepared by the preparation method in the technical scheme or the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film prepared by the preparation method in the technical scheme in a blade protective coating.

The invention provides a three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, which comprises an alloy metal nitride layer and a pure metal nitride layer which are alternately overlapped, wherein the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure; the method comprises the following steps that a layer of alloy metal nitride layer and a layer of pure metal nitride layer which are sequentially stacked are taken as a unit, a plurality of nanocrystalline phase areas and amorphous phase areas exist in one unit or a plurality of units at the same time, and a space three-dimensional network structure is formed by the interfaces of the nanocrystalline phase areas and the amorphous phase areas. In the invention, the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure, so that a nanocrystalline phase region and an amorphous phase region which are coherent with each other of the two modulation layers exist in one unit at the same time, and in the process of depositing a plurality of units, a three-dimensional network structure of a space is formed at the interface of the coherent crystalline phase region and the amorphous region formed in the modulation layer of one or more units, so that the hardness and the toughness of the film layer are improved. The embodiment result shows that the multilayer film provided by the invention has the hardness of 25.7-28.8 GPa and excellent toughness.

Drawings

FIG. 1 is a schematic diagram of the method for preparing a three-dimensional network nano-crystalline/amorphous high-strength high-toughness nano-multilayer film according to the present invention;

FIG. 2 is a SEM image of hardness curves and indentations of samples prepared according to examples of the present invention and comparative examples;

FIG. 3 is a cross-sectional TEM image of a sample prepared in example 1 of the present invention.

Detailed Description

The invention provides a three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, which comprises an alloy metal nitride layer and a pure metal nitride layer which are alternately overlapped, wherein the alloy metal nitride layer and the pure metal nitride layer both have a nanocrystalline and amorphous coexisting structure; the method comprises the following steps that a layer of alloy metal nitride layer and a layer of pure metal nitride layer which are sequentially stacked are taken as a unit, a plurality of nanocrystalline phase areas and amorphous phase areas exist in one unit or a plurality of units at the same time, and a space three-dimensional network structure is formed by the interfaces of the nanocrystalline phase areas and the amorphous phase areas.

In the invention, the number of the units of the high-strength high-toughness nano multilayer film is preferably 40-100, more preferably 50-90, and particularly preferably 50, 71, 83 or 90; the thickness ratio of the alloy metal nitride layer to the pure metal nitride layer in each unit is preferably 10: 1-12 independently, more preferably 10: 1-10 independently, and particularly preferably 10:1, 10:2, 10:4 or 10:10 independently. In a particular embodiment of the invention, the thickness of the alloyed metal nitride layer is preferably 10nm and the thickness of the pure metal nitride layer is preferably 1nm, 2nm, 4nm or 10 nm. The invention limits the thickness ratio of the alloy metal nitride layer and the pure metal nitride layer in the range, and aims to firstly deposit the alloy metal nitride layer with certain thickness and coexisting crystallization and amorphous two phases on the substrate as the template layer, and then deposit the crystallization pure metal nitride layer with different thickness on the template layer, and induce the pure metal nitride to be in the coexisting crystallization and amorphous two phases due to the template layer effect.

In the present invention, the alloy metal nitride layer is preferably Ti₂AlNbN thin film, Ti₃AlN thin film or Ti₂An AlTaN film; the pure metal nitride layer is preferably Zr₃N₄Film, Hf₃N₄Film or Ti₂And (6) N thin films.

The invention also provides a preparation method of the three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film, which comprises the following steps:

argon is used as sputtering gas, nitrogen is used as reaction gas, magnetron sputtering technology is adopted, and alloy metal targets and pure metal targets are used as sputtering targets to respectively and alternately sputter the substrate, so that the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film is obtained.

The preparation method provided by the invention is shown as a schematic diagram in figure 1, the invention utilizes magnetron sputtering technology to firstly obtain an alloy nitride layer with coexisting nanocrystalline and amorphous phases on a substrate as a template layer, then a crystallized pure metal nitride layer is deposited on the alloy metal nitride layer, the coexisting of the nanocrystalline and the amorphous phases is induced in the pure metal nitride layer due to the action of the template layer, a nanocrystalline phase area and an amorphous phase area which simultaneously exist two nanocrystalline layers in one deposition unit by taking the alloy metal nitride and the pure metal nitride as the alloy metal nitride are obtained, then an accumulated deposition unit with repeated alloy metal nitride and pure metal nitride layers is alternately deposited, and in the process of depositing a plurality of units, a spatial three-dimensional network structure is formed at the interface of the eutectic phase area and the amorphous phase area in one or more modulation layers (the alloy metal nitride layer and the pure metal nitride layer) of one or more units, can realize multi-stage regulation and control of hardness and toughness, and provides necessary basic support for reliable application of the multifunctional integrated superhard and super-tough nano-film. The preparation method provided by the invention not only breaks through the simple compound mode that the traditional ceramic/ceramic nano multilayer film prepared by the method has a single structure and is regulated and controlled by phase separation, but also better realizes the breakthrough improvement of the strength and the toughness of the ceramic nano composite film by utilizing the three-dimensional interface effect. In addition, the preparation method provided by the invention has the advantages of simple process, low cost, high repeatability and high yield, and can be used for large-scale industrial production; and no by-product is generated in the preparation process, so that the preparation method is beneficial to environmental protection and can be applied to the blade protective coating of the high thrust-weight ratio aeroengine.

The method takes argon as sputtering gas, the purity of the argon is preferably 99.995-99.999%, and the flow of the argon is preferably 50-80 sccm, and more preferably 60 sccm.

The method takes nitrogen as reaction gas, the purity of the nitrogen is preferably 99.995-99.999%, and the flow rate of the nitrogen is preferably 70-100 sccm, and more preferably 90 sccm.

The invention adopts magnetron sputtering technology, and takes an alloy metal target and a pure metal target as sputtering target materials to respectively and alternately sputter a substrate, thereby obtaining the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film.

Before the sputtering, the vacuum degree of the film coating chamber is preferably controlled to be better than 4 multiplied by 10^-4Pa, the gas impurities in the coating chamber can be discharged to the maximum extent, and the oxidation in the coating process is avoided.

In the present invention, the alloy metal target is preferably Ti₂AlNb target, Ti₃Al target or Ti₂An AlTa target; the pure metal target is preferably a Zr target, a Hf target or a Ti target. In the present invention, the substrate is preferably a silicon wafer.

In the present invention, the substrate surface is preferably parallel to the sputtering target surface, and specifically, it is preferably: and (3) installing the alloy metal target and the pure metal target on corresponding target positions of a multi-target magnetron sputtering coating chamber to enable the surfaces of the substrate and the target materials to be parallel. In the present invention, the target-base distance between the substrate and the sputtering target is preferably 8 to 12cm, and the bias is preferably-80 to-120V, and more preferably-100V.

In the invention, the working pressure in the sputtering process is preferably 0.5-1.2 Pa, and more preferably 0.8 Pa. The invention can ensure the optimal deposition rate by adopting the working air pressure.

In the invention, the sputtering current of the alloy metal target is preferably 0.2-0.6A, the voltage is preferably 250-450V, and more preferably 320V; the sputtering current of the pure metal target is preferably 0.3-0.7A, the voltage is preferably 270-470V, and the voltage is more preferably 340V; the present invention controls the current and voltage held by sputtering within the above ranges, enabling precise control of the thickness of each modulation layer (alloy metal nitride layer and pure metal nitride layer).

In the invention, the deposition rate of the alloy metal target is preferably 15-20 nm/min, more preferably 16-18 nm/min, and further preferably 16.6 nm/min; the deposition rate of the pure metal target is preferably 9-15 nm/min, more preferably 10-13 nm/min, and further preferably 12 nm/min. The thickness of each modulation layer can be accurately controlled by adopting the deposition rate.

In the specific embodiment of the invention, reaction gas and sputtering gas are introduced in the process of depositing the multilayer film, the working pressure in the film coating chamber is adjusted, the current of a sputtering power supply is set, a substrate holder is enabled to alternately stay right above an alloy metal target and a pure metal target for a certain time, a deposition unit for sequentially depositing alloy metal nitride and pure metal nitride is obtained on the surface of the substrate, and then a continuous multilayer composite film structure is formed through accumulation of the deposition unit.

In the invention, the single sputtering time of the alloy metal target is preferably 30-40 s, more preferably 34-38 s, and further preferably 36 s; the single sputtering time of the pure metal target is preferably 2-55 s, more preferably 3-52 s, and further preferably 5s, 10s, 20s or 50 s. The invention adopts the layered deposition technology of multi-target magnetron sputtering to lead a plurality of nano ceramic film deposition units with different thickness modulation ratios (the thickness ratio of two modulation layers in one unit) to be alternately introduced during deposition, thereby realizing the multi-level regulation and control of the hardness and the toughness, breaking through the simple compound mode that the traditional ceramic/ceramic nano multilayer film preparation has single structure and is regulated and controlled by phase separation, and better realizing the breakthrough improvement of the strength and the toughness of the ceramic nano composite film by utilizing the three-dimensional interface effect.

In the invention, before the sputtering, the substrate is preferably cleaned and dried in advance. In the specific embodiment of the invention, the substrate is sequentially placed in acetone, alcohol and deionized water for ultrasonic cleaning, and then dried. In the invention, the ultrasonic cleaning time of the substrate in acetone, alcohol and deionized water is preferably 15-20 min independently; the drying is preferably carried out by blowing with a blower.

After the sputtering is finished, the present invention preferably further includes: and cooling the obtained film to room temperature under a vacuum condition to obtain the three-dimensional reticular nanocrystalline/amorphous high-strength high-toughness nano multilayer film. The invention has no special requirement on the cooling rate, and the film coating chamber can be naturally cooled.

The invention also provides an application of the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film prepared by the preparation method in the technical scheme or the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film prepared by the preparation method in the technical scheme as a blade protective coating, and particularly the three-dimensional reticular nano-crystalline/amorphous high-strength high-toughness nano-multilayer film is applied to a protective coating of an aero-engine blade with a high thrust-weight ratio. The specific method of the application is preferably as follows: the substrate is replaced by the blade to be sputtered, and the high-strength and high-toughness nano multilayer film is formed on the surface of the blade.

The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It is to be understood that the described embodiments are merely exemplary of the invention, and not restrictive of the full scope of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.