CN111441025A - Corrosion-resistant high-entropy alloy film, preparation method and application in seawater environment - Google Patents

Abstract

The invention discloses a corrosion-resistant high-entropy alloy film, a preparation method and its application in seawater environment. The preparation method of the corrosion-resistant high-entropy alloy film includes: using a VAlTiCrCu high-entropy alloy film, and annealing the VAlTiCrCu high-entropy alloy film in a protective atmosphere with a vacuum degree of less than 1.0×10 ⁻³ Pa, so that the VAlTiCrCu high-entropy alloy film is annealed. The annealing temperature used in the annealing treatment is 700-1100° C., the annealing time is 1-3 h, and then cooled to room temperature to obtain a corrosion-resistant high-entropy alloy film. The invention adopts different temperatures to anneal the VAlTiCrCu high-entropy alloy film, so that a new FCC phase is precipitated in the single-phase BCC structure of the VAlTiCrCu high-entropy alloy film, the microstructure changes obviously, the hardness is increased by 20% to 30%, and the elastic modulus is improved 20% to 30%, the self-corrosion current density is further reduced, and it can be used for matrix protection in seawater environment.

Description

Corrosion-resistant high-entropy alloy thin film, preparation method and application thereof in seawater environment application

technical field

The invention relates to the technical field of alloy films and their preparation, in particular to a corrosion-resistant high-entropy alloy film, a preparation method and its application in seawater environment.

Background technique

The traditional alloy system based on one or two elements and compounds has become mature and saturated after long-term research, and the performance of traditional metal materials can no longer meet people's needs in production and life. In this context, a new type of alloy thin film material, high-entropy alloy thin film, has received extensive attention and research in recent years due to its excellent comprehensive properties. The high-entropy alloy film is an alloy film composed of five or more elements, and the content of each element is between 5% and 35%. This design breaks through the design concept of traditional alloys and often has multiple elements. Desirable properties such as excellent abrasion resistance, corrosion resistance, thermal stability and tensile strength at break.

At present, the research in the field of high-entropy alloys is mainly based on as-cast alloys, while the research on high-entropy alloy films is less, and there is less research on the improvement of mechanical properties and corrosion resistance of high-entropy alloy films by heat treatment. At present, high-entropy alloy targets or a combination of a single element and a low-component alloy target are mostly used in the preparation process of high-entropy alloy films. However, the high-entropy alloy target is difficult to control the element content, the production process is complex and the cost is high; and it is difficult to obtain a high-entropy coating with a uniform composition for an independent target using a single element.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a corrosion-resistant high-entropy alloy film with obvious changes in structure, improved hardness, improved elastic modulus, and reduced self-corrosion current density, and a preparation method, as well as the application in seawater environment, thereby overcoming the existing problems. There are technical deficiencies.

In order to realize the above-mentioned purpose of the invention, the present invention has adopted the following technical solutions:

A preparation method of a corrosion-resistant high-entropy alloy film, comprising the following steps:

(1) The magnetron sputtering splicing composite target is used as the cathode target;

(2) Perform mechanical grinding and polishing treatment and cleaning on the surface of the substrate, and put the substrate into the magnetron sputtering cavity and be parallel to the surface of the cathode target in the center of the cavity;

(3) Fill the magnetron sputtering cavity with a protective gas as the working gas, and use the magnetron sputtering technology to perform magnetron sputtering on the spliced composite target in step (1), and the substrate after the treatment in step (2) is used for magnetron sputtering. The VAlTiCrCu high-entropy alloy thin film was obtained by surface deposition;

(4) The VAlTiCrCu high-entropy alloy thin film sample obtained by magnetron sputtering was placed in a quartz tube in a muffle furnace in a protective atmosphere with a vacuum degree lower than 1.0×10 ^-3 Pa;

(5) The VAlTiCrCu high-entropy alloy thin film sample was annealed in a muffle furnace, the annealing temperature was 700-1100 °C, the annealing time was 1-3 h, and the heating rate was 5-10 °C/min;

(6) and then cooled to room temperature with the furnace to obtain a corrosion-resistant high-entropy alloy thin film.

Further, in step (1), the magnetron sputtering splicing composite target includes at least one target cycle arranged periodically in the vertical direction, and each target cycle includes sequentially stacked from top to bottom in the vertical direction. Equal atomic ratio V ₅₀ Al ₅₀ composite target, equi atomic ratio Ti ₅₀ Cr ₅₀ composite target and Cu target; the equi atomic ratio V ₅₀ Al ₅₀ composite target, equiatomic ratio Ti ₅₀ Cr ₅₀ The purity content of the composite target and the Cu target are both 99.9%.

Further, the magnetron sputtering splicing composite target includes 5 to 20 target cycles; in each target cycle, the V ₅₀ Al ₅₀ composite target has a thickness of 5 mm to 45 mm, and the Ti ₅₀ Cr ₅₀ composite target has a thickness of 5 mm to 45 mm. The thickness of the material is 5 mm to 45 mm, and the thickness of the Cu target material is 5 mm to 45 mm.

Further, in step (2), the material of the base body is stainless steel metal material, preferably 304 stainless steel or 316 stainless steel; after the surface of the base body is subjected to mechanical grinding and polishing, petroleum ether, acetone and alcohol are used to carry out ultrasonic cleaning for 20min. .

Further, in step (3), the process conditions adopted by the magnetron sputtering technology include: the sputtering power is 1000W-3000W, the substrate bias voltage is -20V--60V, the substrate temperature is 30-400°C, and the reaction The pressure in the chamber is 3×10 ^-2 to 7×10 ^-2 mbar, the flow rate of the protective gas is 100 to 200 sccm, and the deposition time is 4 to 8 hours; and the protective gas is an inert gas, particularly preferably argon, but not limited to this.

Further, in step (3), before the magnetron sputtering is performed, the reaction chamber is evacuated to a degree of vacuum lower than 1.0×10 ⁻³ Pa, and the composite target is bombarded with Ar ions for 30 minutes to remove the surface of the target material. The impurity and oxides are removed, and the Ar protective atmosphere is passed through the sputtering process to prevent oxides from being generated during the sputtering process; and the surface of the substrate is ion-etched and cleaned for 15 minutes by the principle of glow discharge to remove the oxidation on the surface of the substrate. layers and contaminants.

Further, in step (3), the prepared VAlTiCrCu high-entropy alloy thin film has a single-phase body-centered cubic structure, the molecular formula of the VAlTiCrCu high-entropy alloy thin film is VAlTiCrCu, and the VAlTiCrCu high-entropy alloy thin film contains atomic The following elements are calculated in percentage: V 10-20%, Al 10-20%, Ti 10-20%, Cr 10-30% and Cu 10-30%. The VAlTiCrCu high-entropy alloy thin film is obtained by depositing on the surface of the substrate by magnetron sputtering technology, and is a single-phase body-centered cubic structure composed of vanadium, aluminum, titanium, chromium, and copper elements. In addition, the VAlTiCrCu film is deposited on the surface of the substrate by the magnetron sputtering technology. On the one hand, due to the large size difference between the atoms of each element, it is easy to cause lattice distortion. , Ti and Cr elements, so the VAlTiCrCu film obtained by this method has a single-phase body-centered cubic structure.

Further, the hardness of the VAlTiCrCu high-entropy alloy film is greater than 10 Gpa, the elastic modulus is greater than 220 Gpa, and the self-corrosion current density is lower than 3.62×10 ^-8 A/cm ² ; the thickness of the VAlTiCrCu high-entropy alloy film is 2000nm～4000nm .

The present invention also provides a corrosion-resistant high-entropy alloy film prepared according to the above preparation method. The hardness is 10.03～13.24GPa, the elastic modulus is 202.43～278.36Gpa, and the self-corrosion current density is 5.26×10 ^-9 ～2.87×10 ^-7 A/cm ² .

The invention also provides the application of the corrosion-resistant high-entropy alloy thin film in the field of substrate surface protection in seawater environment.

Compared with the prior art, the present invention has the following beneficial effects:

1) The present invention uses different temperatures to anneal the VAlTiCrCu high-entropy alloy thin film, so that a new FCC phase is precipitated in the single-phase BCC structure of the VAlTiCrCu high-entropy alloy thin film, and the structure changes obviously, and the VAlTiCrCu high-entropy alloy thin film is in the existing high-entropy alloy thin film. On the basis of performance, the hardness is increased by 20% to 30%, the elastic modulus is increased by 20% to 30%, and the self-corrosion current density is further reduced by at most 1 order of magnitude;

2) In the present invention, the targets are sequentially stacked and periodically arranged in the form of V ₅₀ Al ₅₀ -Ti ₅₀ Cr ₅₀ -Cu. While ensuring low production cost and easy control of element types, the atomic ratio of each element in the new target form is It is closer to 1:1:1:1:1, which is beneficial to obtain the highest mixing entropy in the system, thereby inhibiting the formation of intermetallic compounds, strengthening the solid solution of each element, and obtaining VAlTiCrCu high entropy with more uniform composition and better performance. Alloy film;

3) The VAlTiCrCu high-entropy alloy film in the present invention is composed of corrosion-resistant components V, Al, Ti, Cr, and Cu on the one hand; on the other hand, the magnetron sputtering technology is used, and the constituent elements contain a large number of body-centered cubic structures Therefore, the VAlTiCrCu high-entropy alloy film has high hardness and excellent corrosion resistance, its hardness is higher than 10Gpa, its elastic modulus is higher than 220Gpa, and its self-corrosion current density is low. 3.62×10 ^-8 A/cm ² , so it is a wear-resistant and corrosion-resistant material, which can well protect the substrate in harsh environments with high wear and corrosion, such as substrate protection in seawater environments.

Description of drawings

FIG. 1 is a schematic cross-sectional structure diagram of the VAlTiCrCu splicing composite target in Examples 1 to 3 of the present invention.

FIG. 2 is the XRD diffraction patterns of the VAlTiCrCu high-entropy alloy thin films prepared in Examples 1 to 3 of the present invention and the corrosion-resistant VAlTiCrCu high-entropy alloy thin films after annealing treatment.

3 is a dynamic polarization curve diagram obtained by electrochemical testing of the VAlTiCrCu high-entropy alloy thin films prepared in Examples 1 to 3 of the present invention and the corrosion-resistant VAlTiCrCu high-entropy alloy thin films after annealing treatment.

Detailed ways

The technical solutions of the present invention will be described in further detail below with reference to several preferred embodiments and accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. It should be pointed out that the following examples are intended to facilitate the understanding of the present invention, but do not have any limiting effect on it. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention. In the following examples, the test methods without specific conditions are generally in accordance with conventional conditions.

The invention is mainly aimed at the high-entropy alloy thin film, and the use of heat treatment to improve the mechanical properties and corrosion resistance of the high-entropy alloy thin film is of great significance.

Example 1

In this embodiment, the base material is 304 stainless steel, and the surface of the base is a VAlTiCrCu high-entropy alloy film with a single-phase body-centered cubic structure.

The preparation method of the VAlTiCrCu high-entropy alloy thin film is as follows:

Using magnetron sputtering technology, a VAlTiCrCu high-entropy alloy thin film is prepared on the surface of the substrate, which specifically includes the following steps:

(1) As shown in Fig. 1, select V ₅₀ Al ₅₀ target with equal atomic ratio, Ti ₅₀ Cr ₅₀ target and Cu target with equal atomic ratio with raw material purity ≥99.9%, and follow V ₅₀ Al ₅₀ in the vertical direction -Ti ₅₀ Cr ₅₀ -Cu in the order of stacking and arranging targets with thicknesses of 20mm, 20mm, and 10mm from top to bottom, this is one target period; then, including 12 target periods in the vertical direction, forming a splicing composite target.

(2) The surface of the substrate is subjected to mechanical grinding and polishing, and then ultrasonically cleaned with petroleum ether, acetone and alcohol for 20 minutes in turn, and then dried with nitrogen; The target surfaces are parallel. Vacuum was evacuated to less than 10 ^-3 Pa before deposition, the composite target was bombarded with Ar ions for 30 minutes, and the substrate sample was ion-etched for 15 minutes.

(3) The reaction chamber is filled with 99.99 wt.% high-purity argon gas with a flow rate of 150 sccm, and the spliced composite target in the magnetron sputtering step (1) is deposited on the surface of the substrate after the step (2) for 6 hours, to obtain VAlTiCrCu high-entropy alloy thin film, during the sputtering process, the parameters set the substrate temperature to 300 °C, the sputtering power to 2000 W, the substrate bias to -50 V, and the pressure in the reaction chamber to be 6×10 ^-2 mbar to prepare the VAlTiCrCu high-entropy alloy. film.

The hardness, elastic modulus and corrosion resistance of the VAlTiCrCu high-entropy alloy film obtained by magnetron sputtering are improved, and the specific steps are as follows:

(1) The prepared VAlTiCrCu high-entropy alloy thin film sample is placed in a quartz tube in a muffle furnace and evacuated to a degree of vacuum below 10 ^-3 Pa;

(2) The sample was annealed in a muffle furnace, the heating rate was 10°C/min, the annealing temperature was controlled at 700°C, the annealing time was 3h, and a sufficient amount of high-purity argon was introduced during the protection;

(3) The VAlTiCrCu high-entropy alloy thin film sample is heated from room temperature to a specified temperature and then subjected to heat preservation treatment, and then cooled to room temperature with the furnace to obtain a corrosion-resistant high-entropy alloy thin film.

The VAlTiCrCu high-entropy alloy thin film (as a control) and the corrosion-resistant high-entropy alloy thin film sample prepared in the above embodiment are tested as follows:

1. The composition and structure of the VAlTiCrCu high-entropy alloy thin film sample were analyzed by X-ray diffraction, as shown in Figure 3.

2. The VAlTiCrCu high-entropy alloy thin film sample was indented with six points with a depth of 200 nm on the surface of the VAlTiCrCu high-entropy alloy thin film sample by a nanoindenter (MTS Corporation, G200), and the hardness and elastic modulus were measured, and the average value was calculated according to the measurement results. The values are shown in Table 2.

3. Electrochemical tests were performed on the VAlTiCrCu high-entropy alloy thin film samples before annealing and after annealing at 700 °C, and their dynamic polarization curves were obtained, as shown in Figure 3; the specific values of their self-corrosion potential and self-corrosion current density are shown in Table 3 shown.

Example 2

In this embodiment, the base material is 304 stainless steel, and the base surface is a VAlTiCrCu high-entropy alloy thin film.

The preparation method of the VAlTiCrCu high-entropy alloy thin film is as follows:

Using magnetron sputtering technology, a VAlTiCrCu high-entropy alloy thin film is prepared on the surface of the substrate, which specifically includes the following steps:

(1) As shown in Fig. 1, select V ₅₀ Al ₅₀ target with equal atomic ratio, Ti ₅₀ Cr ₅₀ target and Cu target with equal atomic ratio with raw material purity ≥99.9%, and follow V ₅₀ Al ₅₀ in the vertical direction -Ti ₅₀ Cr ₅₀ -Cu in the order of stacking and arranging targets with thicknesses of 20mm, 20mm, and 10mm from top to bottom, this is one target period; then, including 12 target periods in the vertical direction, forming a splicing composite target.

(2) The surface of the substrate is subjected to mechanical grinding and polishing, and then ultrasonically cleaned with petroleum ether, acetone and alcohol for 20 minutes in turn, and then dried with nitrogen; The target surfaces are parallel. Vacuum was evacuated to less than 10 ^-3 Pa before deposition, the composite target was bombarded with Ar ions for 30 minutes, and the substrate sample was ion-etched for 15 minutes.

(3) The reaction chamber is filled with 99.99 wt.% high-purity argon gas with a flow rate of 150 sccm, and the spliced composite target in the magnetron sputtering step (1) is deposited on the surface of the substrate after the step (2) for 6 hours, to obtain VAlTiCrCu high-entropy alloy thin film, during the sputtering process, the parameters set the substrate temperature as 300℃, the sputtering power as 2000W, the substrate bias as -50V, and the pressure in the reaction chamber as 4×10 ^-2 mbar to prepare the VAlTiCrCu high-entropy alloy. film.

The hardness, elastic modulus and corrosion resistance of the VAlTiCrCu high-entropy alloy film obtained by magnetron sputtering are improved, and the specific steps are as follows:

(1) The prepared VAlTiCrCu high-entropy alloy thin film sample is placed in a quartz tube in a muffle furnace and evacuated to a vacuum degree below 10 ^-3 Pa;

(2) The sample was annealed in a muffle furnace, the heating rate was 10°C/min, the annealing temperature was controlled at 900°C, the annealing time was 2h, and a sufficient amount of high-purity argon was introduced during the protection;

(3) The VAlTiCrCu high-entropy alloy thin film sample is heated from room temperature to a specified temperature and then subjected to heat preservation treatment, and then cooled to room temperature with the furnace to obtain a corrosion-resistant high-entropy alloy thin film, in which BCC and FCC exist when both are the same.

The VAlTiCrCu high-entropy alloy thin film (as a control) and the corrosion-resistant high-entropy alloy thin film sample prepared in the above embodiment are tested as follows:

1. The composition and structure of the VAlTiCrCu high-entropy alloy thin film sample were analyzed by X-ray diffraction, as shown in Figure 2.

2. The VAlTiCrCu high-entropy alloy thin film sample was indented with six points with a depth of 200 nm on the surface of the VAlTiCrCu high-entropy alloy thin film sample by a nanoindenter (MTS Corporation, G200), and the hardness and elastic modulus were measured, and the average value was calculated according to the measurement results. The values are shown in Table 2.

3. Electrochemical tests were performed on the VAlTiCrCu high-entropy alloy thin film samples before annealing and after annealing at 900 °C, and their dynamic polarization curves were obtained, as shown in Figure 3; the specific values of their self-corrosion potential and self-corrosion current density are shown in Table 3 shown.

Example 3

In this embodiment, the base material is 304 stainless steel, and the base surface is a VAlTiCrCu high-entropy alloy thin film.

The preparation method of the VAlTiCrCu high-entropy alloy thin film is as follows:

Using magnetron sputtering technology, the VAlTiCrCu high-entropy alloy thin film is prepared on the surface of the substrate, which mainly includes the following steps:

(1) As shown in Fig. 1, select V ₅₀ Al ₅₀ target with equal atomic ratio, Ti ₅₀ Cr ₅₀ target and Cu target with equal atomic ratio with raw material purity ≥99.9%, and follow V ₅₀ Al ₅₀ in the vertical direction -Ti ₅₀ Cr ₅₀ -Cu in the order of stacking and arranging targets with thicknesses of 20mm, 20mm, and 10mm from top to bottom, this is one target period; then, including 12 target periods in the vertical direction, forming a splicing composite target.

(2) The surface of the substrate is subjected to mechanical grinding and polishing, and then ultrasonically cleaned with petroleum ether, acetone and alcohol for 20 minutes in turn, and then dried with nitrogen; The target surfaces are parallel. Vacuum was evacuated to less than 10 ^-3 Pa before deposition, the composite target was bombarded with Ar ions for 30 minutes, and the substrate sample was ion-etched for 15 minutes.

(3) The reaction chamber is filled with 99.99 wt.% high-purity argon gas with a flow rate of 150 sccm, and the spliced composite target in the magnetron sputtering step (1) is deposited on the surface of the substrate after the step (2) for 6 hours, to obtain VAlTiCrCu high-entropy alloy thin film, during the sputtering process, the parameters set the substrate temperature to 300°C, the sputtering power to 2000W, the substrate bias voltage to -50V, and the pressure in the reaction chamber to be 5×10 ^-2 mbar to prepare the VAlTiCrCu high-entropy alloy. film.

The hardness, elastic modulus and corrosion resistance of the VAlTiCrCu high-entropy alloy film obtained by magnetron sputtering are improved, and the specific steps are as follows:

(1) The prepared VAlTiCrCu high-entropy alloy thin film sample is placed in a quartz tube in a muffle furnace and evacuated to a vacuum degree below 10 ^-3 Pa;

(2) The sample was annealed in a muffle furnace, the heating rate was 10°C/min, the annealing temperature was controlled to 1100°C, the annealing time was 1h, and a sufficient amount of high-purity argon was introduced during the protection;

(3) The VAlTiCrCu high-entropy alloy thin film sample is heated from room temperature to a specified temperature and then subjected to heat preservation treatment, and then cooled to room temperature with the furnace to obtain a corrosion-resistant high-entropy alloy thin film, in which BCC and FCC exist when both are the same.

The VAlTiCrCu high-entropy alloy thin film (as a control) and the corrosion-resistant high-entropy alloy thin film sample prepared in the above embodiment are tested as follows:

1. The composition and structure of the VAlTiCrCu high-entropy alloy thin film sample were analyzed by X-ray diffraction, as shown in Figure 2.

2. The VAlTiCrCu high-entropy alloy thin film sample was indented with six points with a depth of 200 nm on the surface of the VAlTiCrCu high-entropy alloy thin film sample by a nanoindenter (MTS Corporation, G200), and the hardness and elastic modulus were measured, and the average value was calculated according to the measurement results. The values are shown in Table 2.

3. Electrochemical tests were performed on the VAlTiCrCu high-entropy alloy thin film samples before annealing and after annealing at different temperatures, and their dynamic polarization curves were obtained, as shown in Figure 3; the specific values of their self-corrosion potential and self-corrosion current density are shown in Table 3. shown.

The composition and structure of the corrosion-resistant VAlTiCrCu high-entropy alloy film samples prepared in Examples 1-3 were analyzed by X-ray diffraction. Figure 2 shows the VAlTiCrCu high-entropy alloy film (as a control) and the corrosion-resistant VAlTiCrCu high-entropy alloy after annealing treatment. XRD diffraction pattern of the thin film. Before the annealing treatment and after the annealing treatment at 700 °C, the structure is a single-phase BCC structure. After annealing treatment at 900 °C and 1100 °C respectively, the new FCC structure is precipitated on the basis of the original BCC structure, which is BCC and FCC. The same structure exists.

The elemental composition content of the VAlTiCrCu high-entropy alloy thin film sample (as a control) prepared in Example 1-3 is shown in Table 1:

Table 1: Elemental composition content of VAlTiCrCu high-entropy alloy thin films

element V Al Ti Cr Cu Content (at.%) 12.93 17.26 14.43 26.33 29.05

It can be seen from Table 1 that the atomic percentage content of each element in the VAlTiCrCu high-entropy alloy thin film sample meets the requirement that the atomic percentage of the elements in the high-entropy alloy is 5% to 35%.

Six points with a depth of 200 nm were pressed into the surfaces of the three film samples after annealing in Examples 1-3 by a nano-indentation device, and the hardness and elastic modulus were measured. The results are shown in Table 2 below.

Table 2: Hardness and elastic modulus of VAlTiCrCu high-entropy alloy films before and after annealing

Annealing temperature not processed 700℃ 900℃ 1100℃ Elastic modulus/Gpa 228.24 202.43 275.25 278.36 Hardness/Gpa 10.36 10.03 13.24 12.68

It can be seen from Table 2 that the VAlTiCrCu high-entropy alloy thin films before and after annealing have high hardness and elastic modulus. It is worth mentioning that the corrosion-resistant VAlTiCrCu high-entropy alloy thin film samples after annealing at 900 °C and 1100 °C have high entropy alloy films. Both hardness and elastic modulus are increased by 20% to 30%.

Electrochemical tests were performed on the VAlTiCrCu corrosion-resistant high-entropy alloy thin film samples before and after annealing in Examples 1-3, and the specific values of their self-corrosion potential and self-corrosion current density are shown in Table 3 below.

Table 3: Self-corrosion potential and self-corrosion current density of VAlTiCrCu high-entropy alloy films before and after annealing

It can be seen from Table 3 that the corrosion resistance of the VAlTiCrCu corrosion-resistant high-entropy alloy film is improved to varying degrees after annealing. Among them, after annealing at 1100 °C, the self-corrosion current density even decreased by an order of magnitude, and the corrosion resistance was greatly improved after annealing.

Example 4

In this embodiment, the base material is 304 stainless steel, and the base surface is a VAlTiCrCu high-entropy alloy thin film.

The preparation method of the VAlTiCrCu high-entropy alloy thin film is as follows:

Using magnetron sputtering technology, the VAlTiCrCu high-entropy alloy thin film is prepared on the surface of the substrate, which mainly includes the following steps:

(1) Select V ₅₀ Al ₅₀ targets with an equal atomic ratio, Ti ₅₀ Cr ₅₀ targets and Cu targets with an equal atomic ratio of raw material purity ≥99.9%, in the vertical direction according to V ₅₀ Al ₅₀ -Ti ₅₀ Cr ₅₀ - Each target with thicknesses of 20mm, 20mm, and 10mm is stacked in the order of Cu from top to bottom, which is one target cycle; then, 20 target cycles are included in the vertical direction to form a spliced composite target.

(2) The surface of the substrate is subjected to mechanical grinding and polishing, and then ultrasonically cleaned with petroleum ether, acetone and alcohol for 20 minutes in turn, and then dried with nitrogen; The target surfaces are parallel. Vacuum was evacuated to less than 10 ^-3 Pa before deposition, the composite target was bombarded with Ar ions for 30 minutes, and the substrate sample was ion-etched for 15 minutes.

(3) The reaction chamber is filled with 99.99 wt.% high-purity argon gas with a flow rate of 100 sccm, and the spliced composite target in the magnetron sputtering step (1) is deposited on the surface of the substrate after the step (2) for 8 hours, to obtain During the sputtering process of VAlTiCrCu high-entropy alloy thin film, the parameters set the substrate temperature to 400°C, the sputtering power to 1000W, the substrate bias to -60V, and the pressure in the reaction chamber to be 3×10 ^-2 mbar to prepare the VAlTiCrCu high-entropy alloy. film.

The hardness, elastic modulus and corrosion resistance of the VAlTiCrCu high-entropy alloy film obtained by magnetron sputtering are improved, and the specific steps are as follows:

(1) The prepared VAlTiCrCu high-entropy alloy thin film sample is placed in a quartz tube in a muffle furnace and evacuated to a vacuum degree below 10 ^-3 Pa;

(2) The sample was annealed in a muffle furnace, the heating rate was 5°C/min, the annealing temperature was controlled at 900°C, the annealing time was 1h, and a sufficient amount of high-purity argon was introduced during the protection;

(3) The VAlTiCrCu high-entropy alloy thin film sample is heated from room temperature to a specified temperature and then subjected to heat preservation treatment, and then cooled to room temperature with the furnace to obtain a corrosion-resistant high-entropy alloy thin film.

Example 5

In this embodiment, the base material is 304 stainless steel, and the base surface is a VAlTiCrCu high-entropy alloy thin film.

The preparation method of the VAlTiCrCu high-entropy alloy thin film is as follows:

Using magnetron sputtering technology, the VAlTiCrCu high-entropy alloy thin film is prepared on the surface of the substrate, which mainly includes the following steps:

(1) Select V ₅₀ Al ₅₀ targets with an equal atomic ratio, Ti ₅₀ Cr ₅₀ targets and Cu targets with an equal atomic ratio of raw material purity ≥99.9%, in the vertical direction according to V ₅₀ Al ₅₀ -Ti ₅₀ Cr ₅₀ - Each target with thicknesses of 20mm, 20mm, and 10mm is stacked in the order of Cu from top to bottom, which is one target cycle; then, 5 target cycles are included in the vertical direction to form a spliced composite target.

(2) The surface of the substrate is subjected to mechanical grinding and polishing, and then ultrasonically cleaned with petroleum ether, acetone and alcohol for 20 minutes in turn, and then dried with nitrogen; The target surfaces are parallel. Vacuum was evacuated to less than 10 ^-3 Pa before deposition, the composite target was bombarded with Ar ions for 30 minutes, and the substrate sample was ion-etched for 15 minutes.

(3) The reaction chamber is filled with 99.99 wt.% high-purity argon gas with a flow rate of 200 sccm, and the spliced composite target in the magnetron sputtering step (1) is deposited on the surface of the substrate after the step (2) for 4 hours to obtain VAlTiCrCu high-entropy alloy thin film, during the sputtering process, the parameters set the substrate temperature to 30°C, the sputtering power to 3000W, the substrate bias to -20V, and the pressure in the reaction chamber to be 7×10 ^-2 mbar to prepare the VAlTiCrCu high-entropy alloy. film.

The hardness, elastic modulus and corrosion resistance of the VAlTiCrCu high-entropy alloy film obtained by magnetron sputtering are improved, and the specific steps are as follows:

(1) The prepared VAlTiCrCu high-entropy alloy thin film sample is placed in a quartz tube in a muffle furnace and evacuated to a vacuum degree below 10 ^-3 Pa;

(2) The sample was annealed with a muffle furnace, the heating rate was 8°C/min, the annealing temperature was controlled at 900°C, the annealing time was 3h, and a sufficient amount of high-purity argon was introduced during the protection;

(3) The VAlTiCrCu high-entropy alloy thin film sample is heated from room temperature to a specified temperature and then subjected to heat preservation treatment, and then cooled to room temperature with the furnace to obtain a corrosion-resistant high-entropy alloy thin film.

Comparative Example 1

Please refer to CN 110129731A. In this comparative example, the base material is stainless steel, and the surface of the base body is a CoCrFeMnNi high-entropy alloy thin film.

The preparation method of the CoCrFeMnNi high-entropy alloy thin film is as follows:

Using magnetron sputtering technology, the CoCrFeMnNi high-entropy alloy thin film is prepared on the surface of the substrate, which mainly includes the following steps:

(1) A high-purity Co ₂₀ Cr ₂₀ Fe ₂₀ Mn ₂₀ Ni ₂₀ (at%) alloy with a purity of 99.99%, heat preservation at 1000° C. and homogenization treatment for 48 hours was used as the target material.

(2) Polish the surface of the substrate, and then perform ultrasonic cleaning with acetone, alcohol and deionized water for 15 minutes in turn to remove impurities and dirt on the surface, fix the substrate on the circular baffle and send it into the sampling chamber, and vacuum until Vacuum degree ≤ 5×10 ^-5 Pa; use Ar ions to pre-sputter the target for 30 minutes.

(3) The vacuum degree of the sample injection chamber is ≤2.5×10 ^-6 Pa, and the sample is sent into the sputtering chamber. After the vacuum degree in the reaction chamber was ≤2.5×10 ^-6 Pa, argon gas with a flow rate of 20sccm was charged, and deposited on the surface of the substrate for 30min to obtain a CoCrFeMnNi high-entropy alloy thin film. During the sputtering process, the sputtering power was set to 150W.

(4) After 10 times of liquid nitrogen cryogenic treatment, the obtained CoCrFeMnNi high-entropy alloy film has a hardness of 9.1 GPa and an elastic modulus of 152 GPa.

Most of the high-entropy alloy targets in this comparative example are integrally formed targets, and the type and composition of the target are not easy to control, while the high-entropy alloy target in the present invention is not only easy to control the type and composition, but also has excellent performance.

Comparative Example 2

This comparative example is basically the same as that of Example 1, except that the annealing temperature is 400°C.

After testing, the structure of the VAlTiCrCu high-entropy alloy thin film prepared in this control example is a single-phase BCC structure before and after the annealing treatment. The element content of the VAlTiCrCu high-entropy alloy thin film sample prepared in this comparative example is shown in Table 4:

Table 4: Elemental composition content of VAlTiCrCu high-entropy alloy thin film in Comparative Example 2

element V Al Ti Cr Cu Content (at.%) 12.93 17.26 14.43 26.33 29.05

It can be seen from Table 4 that the atomic percentage content of each element in the VAlTiCrCu high-entropy alloy thin film sample meets the requirement that the atomic percentage content of the elements in the high-entropy alloy is 5% to 35%.

Six points with a depth of 200 nm were pressed into the surface of the annealed film sample in this comparative example by a nano-indentation device, and the hardness and elastic modulus were measured. The measurement results are shown in Table 5 below.

Table 5: Hardness and elastic modulus of VAlTiCrCu high-entropy alloy films before and after annealing

Annealing temperature not processed 400℃ Elastic modulus/Gpa 228.24 180.09 Hardness/Gpa 10.36 7.71

It can be seen from Table 5 that the hardness and elastic modulus of the VAlTiCrCu high-entropy alloy thin film samples decreased by 20% to 30% after annealing at 400 °C.

Electrochemical tests were performed on the VAlTiCrCu corrosion-resistant high-entropy alloy thin film samples before and after annealing in this comparative example, and the specific values of the self-corrosion potential and self-corrosion current density are shown in Table 6 below.

Table 6: Self-corrosion potential and self-corrosion current density of VAlTiCrCu high-entropy alloy films before and after annealing

It can be seen from Table 6 that the corrosion resistance of the VAlTiCrCu high-entropy alloy film decreased slightly after being annealed at 400 °C.

The aspects, embodiments, features, and examples of the present invention are to be considered in all respects illustrative and not intended to limit the invention, the scope of which is defined only by the claims. Other embodiments, modifications, and uses will be apparent to those skilled in the art without departing from the spirit and scope of the claimed invention.

The use of headings and sections in this application is not meant to limit the invention; each section is applicable to any aspect, embodiment or feature of the invention.

Throughout this specification, where a composition is described as having, comprising or including particular components, or where a process is described as having, comprising or including particular process steps, it is contemplated that the compositions of the present teachings will also be substantially The above consists of or consists of the recited components, and the processes taught herein also consist essentially of, or consist of, the recited process steps.

The use of the terms "include, includes, including," "have, has, or having" should generally be understood to be open-ended and not limiting unless specifically stated otherwise.

It should be understood that the order of the steps or the order in which the particular actions are performed is not critical so long as the present teachings remain operable. Furthermore, two or more steps or actions may be performed simultaneously.

In addition, the inventors of the present application also carried out experiments with other raw materials, technological operations and technological conditions mentioned in this specification with reference to the foregoing examples, and all obtained satisfactory results.

Although the present invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions and/or additions and the like may be made without departing from the spirit and scope of the invention Effects replace elements of the described embodiments. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is not intended herein to limit the invention to the particular embodiments disclosed for carrying out the invention, but it is intended that this invention include all embodiments falling within the scope of the appended claims. Furthermore, unless specifically stated, any use of the terms first, second, etc. does not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another.

Claims (10)

1. The preparation method of the corrosion-resistant high-entropy alloy film is characterized by comprising the following steps of:

(1) the magnetron sputtering splicing composite target is used as a cathode target material;

(2) carrying out mechanical grinding and polishing treatment and cleaning on the surface of the matrix, and putting the matrix into a magnetron sputtering cavity, wherein the matrix is parallel to the surface of a cathode target material in the center of the cavity;

(3) filling protective gas into the magnetron sputtering cavity as working gas, performing magnetron sputtering on the spliced composite target in the step (1) by adopting a magnetron sputtering technology, and depositing on the surface of the substrate treated in the step (2) to obtain a VAlTiCrCu high-entropy alloy film;

(4) putting a VAlTiCrCu high-entropy alloy film sample obtained by magnetron sputtering in a quartz tube in a muffle furnace, and controlling the vacuum degree to be lower than 1.0 × 10^–3Pa in a protective atmosphere;

(5) annealing the VAlTiCrCu high-entropy alloy film sample by using a muffle furnace, wherein the annealing temperature is 700-1100 ℃, the annealing time is 1-3 h, and the heating rate is 5-10 ℃/min;

(6) and then cooling to room temperature along with the furnace to obtain the corrosion-resistant high-entropy alloy film.

2. The method for preparing a corrosion-resistant high-entropy alloy thin film according to claim 1, wherein, in the step (1), the magnetron sputtering splicing composite target comprises at least one target period arranged periodically in the vertical direction, and each target period comprises V with equal atomic ratio which are sequentially stacked from top to bottom in the vertical direction₅₀Al₅₀Composite target material, equal atomic ratio Ti₅₀Cr₅₀A composite target material and a Cu target material; v of the same atomic ratio₅₀Al₅₀Composite target material, equal atomic ratio Ti₅₀Cr₅₀The purity content of the composite target and the Cu target is 99.9 percent.

3. The method for preparing the corrosion-resistant high-entropy alloy thin film according to claim 2, wherein the magnetron sputtering splicing composite target comprises 5-20 target periods; in each target period, the V₅₀Al₅₀The thickness of the composite target material is 5 mm-45 mm, and the Ti₅₀Cr₅₀The thickness of the composite target material is 5 mm-45 mm, and the thickness of the Cu target material is 5 mm-45 mm.

4. The method for preparing the corrosion-resistant high-entropy alloy film according to claim 1, wherein in the step (2), the substrate is made of a stainless steel metal material, and after mechanical polishing treatment is performed on the surface of the substrate, petroleum ether, acetone and alcohol are used for ultrasonic cleaning for 20 min.

5. The method for preparing the corrosion-resistant high-entropy alloy film according to claim 1, wherein in the step (3), the magnetron sputtering technology adopts the process conditions that the sputtering power is 1000W-3000W, the substrate bias voltage is-20V-60V, the substrate temperature is 30-400 ℃, and the pressure in the reaction cavity is 3 × 10^-2～7×10^-2mbar, the flow rate of the protective gas is 100-200 sccm, and the deposition time is 4-8 h; and the protective gas is an inert gas.

6. The method for preparing a corrosion-resistant high-entropy alloy thin film according to claim 1, wherein in the step (3), before magnetron sputtering, the reaction chamber is vacuumized to a vacuum degree of less than 1.0 × 10^–3And Pa, bombarding the composite target for 30min by utilizing Ar ions, and carrying out ion etching cleaning on the surface of the substrate for 15min by utilizing a glow discharge principle.

7. The method for preparing the corrosion-resistant high-entropy alloy thin film according to claim 1, wherein in the step (3), the prepared VAlTiCrCu high-entropy alloy thin film is of a single-phase body-centered cubic structure, the molecular formula of the VAlTiCrCu high-entropy alloy thin film is VAlTiCrCu, and the VAlTiCrCu high-entropy alloy thin film contains the following elements in atomic percentage: 10-20% of V, 10-20% of Al, 10-20% of Ti, 10-30% of Cr and 10-30% of Cu.

8. The method for preparing the corrosion-resistant high-entropy alloy thin film according to claim 7, wherein the VAlTiCrCu high-entropy alloy thin film has hardness of more than 10Gpa, elastic modulus of more than 220Gpa and self-corrosion current density of less than 3.62 × 10^-8A/cm²(ii) a The thickness of the VAlTiCrCu high-entropy alloy film is 2000 nm-4000 nm.

9. According to the rightThe corrosion-resistant high-entropy alloy thin film prepared by the preparation method of any one of claims 1 to 8, wherein the corrosion-resistant high-entropy alloy thin film is of a structure in which a body-centered cubic structure and a face-centered cubic structure coexist, the hardness of the corrosion-resistant high-entropy alloy thin film is 10.03 to 13.24GPa, the elastic modulus of the corrosion-resistant high-entropy alloy thin film is 202.43 to 278.36Gpa, and the self-corrosion current density of the corrosion-resistant high-entropy alloy thin film is 5.26 × 10^-9～2.87×10^-7A/cm²。

10. The use of the corrosion-resistant high-entropy alloy thin film of claim 9 in the field of protection in a seawater environment.

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