WO2021104108A1 - Marine-microbial-corrosion-resistant high-entropy alloy, preparation method therefor and use thereof - Google Patents

Abstract

Disclosed is a marine-microbial-corrosion-resistant high-entropy alloy, the chemical general formula of the marine-microbial-corrosion-resistant high-entropy alloy being Al_0.1CoCrFeNiCu_x, wherein x is the molar fraction of Cu, and 0.3 ≤ x ≤ 0.5. The marine-microbial-corrosion-resistant high-entropy alloy has both a strong corrosion resistance and outstanding antimicrobial properties, and can efficiently resist corrosion induced by marine microorganisms. Further provided is a method for preparing the marine-microbial-corrosion-resistant high-entropy alloy and the use thereof.

Description

High-entropy alloy resistant to marine microbial corrosion and preparation method and application thereof Technical field

The invention relates to the technical field of metal alloy materials, in particular to a high-entropy alloy resistant to marine microbial corrosion, and a preparation method and application thereof.

Background technique

Marine corrosion is a major problem faced by marine engineering. According to statistics, the annual marine corrosion loss is about 0.8 trillion U.S. dollars, accounting for 1/3 of the global total corrosion (2.4 trillion U.S. dollars). At present, key structural parts such as seawater pipelines, pump valves, heat exchangers, etc. mostly use traditional alloy materials such as alloy steel, stainless steel, and nickel-based corrosion-resistant alloys. A dense oxide film/passivation film is formed on the surface to protect the alloy. Free from corrosive ions (such as chloride ions in sea water). However, in addition to marine salt spray, seawater ionization, and chemical corrosion, marine metal materials also face severe marine microbial corrosion (MIC). In the marine environment, microorganisms adhere to the surface of the material to form an uneven biofilm, which accelerates the corrosion of metal components through their own metabolic activities, causing the material to fail. According to statistics, the destruction of materials related to marine microbial corrosion accounts for 70%-80% of the total marine materials. Therefore, it is of great significance to develop an alloy resistant to marine microbial corrosion.

technical problem

In view of this, the present invention provides a high-entropy alloy resistant to marine microbial corrosion and a preparation method and application thereof. The high-entropy alloy resistant to marine microbial corrosion has both strong corrosion resistance and outstanding antibacterial properties. Can effectively resist the corrosion of marine microorganisms.

Technical solutions

In the first aspect, the present invention provides a high-entropy alloy resistant to marine microbial corrosion. The general chemical formula of the high-entropy alloy resistant to marine microbial corrosion is Al _0.1 CoCrFeNiCu _x , where x is the mole fraction of Cu, 0.3≤ x≤0.5.

In one embodiment of the present invention, in the general chemical formula, the range of x is 0.45≤x≤0.5. In another embodiment, the range of x is 0.3≤x≤0.4. For example, x can be, but is not limited to, 0.3, or 0.32, or 0.35, or 0.38, or 0.4, or 0.42, or 0.45, or 0.48, or 0.5.

Further, optionally, the general chemical formula of the high-entropy alloy resistant to marine microbial corrosion is Al _0.1 CoCrFeNiCu _0.5 .

The marine microbial corrosion resistant high-entropy alloy under the general chemical formula of the present invention can obviously inhibit the growth of microbes on its surface, and has excellent marine microbial corrosion resistance.

Optionally, the crystal structure of the high-entropy alloy resistant to corrosion by marine microorganisms is a face-centered cubic structure. The high-entropy alloy resistant to marine microbial corrosion of the crystal structure has high strength, high elongation force, and strong toughness.

Optionally, the purity of Al, Co, Cr, Fe, Ni, and Cu in the high-entropy alloy resistant to marine microbial corrosion is greater than 99.9%.

Optionally, the antibacterial rate of the high-entropy alloy resistant to marine microbial corrosion can reach more than 90%. The high-entropy alloy resistant to corrosion by marine microorganisms of the present invention can effectively inhibit the corrosion of marine microorganisms, wherein the marine microorganisms may include, but are not limited to, Pseudomonas aeruginosa.

Further, optionally, the antibacterial rate of the high-entropy alloy resistant to corrosion by marine microorganisms reaches more than 95%.

In the second aspect, the present invention also provides a method for preparing a high-entropy alloy resistant to marine microbial corrosion, including:

(1) After surface pretreatment of Al, Co, Cr, Fe, Ni and Cu metal elementary raw materials, the mole fraction ratio of 0.1:1:1:1:1:x is added to the smelting equipment, where 0.3≤x ≤0.5;

(2) First, melt the elemental metal raw materials into an alloy liquid under an inert atmosphere, obtain an alloy ingot after cooling, and turn the alloy ingot over four times;

(3) Repeat the step (2) at least twice, and after the elemental metal raw materials are evenly smelted, they are molded into a fixed mold to obtain a high-entropy alloy resistant to marine microbial corrosion.

Optionally, the metal elemental raw materials of Al, Co, Cr, Fe, Ni, and Cu are stacked in the smelting equipment in order of melting point from small to large. In one embodiment, Al and Cu are placed on the bottom, Co, Fe, and Ni are placed in the middle, and Cr is placed on the top.

Optionally, the purity of the metal elementary raw materials of Al, Co, Cr, Fe, Ni, and Cu are all greater than 99.9%.

Further, optionally, the purity of the metal elementary raw materials of Al, Co, Cr, Fe, Ni, and Cu are all greater than 99.99%.

Optionally, the surface pretreatment process includes: removing the surface oxide scale of the elemental metal raw materials of Al, Co, Cr, Fe, Ni, and Cu, and then performing ultrasonic cleaning and drying. Wherein, the ultrasonic cleaning process can be, but not limited to, performed in absolute ethanol.

Optionally, the smelting equipment is a non-consumable vacuum electric arc furnace; before the smelting equipment smelts the high-entropy alloy resistant to marine microbial corrosion, metallic titanium is smelted to remove impurities in the smelting equipment. By smelting titanium metal first, the free oxygen, nitrogen and other impurities contained in the smelting equipment can be effectively absorbed.

Optionally, the inert atmosphere in the step (2) can be realized by performing a vacuuming process on the smelting equipment at least once. Each time the vacuuming process includes vacuuming the melting equipment first, and then introducing inert gas; wherein, the inert gas includes argon.

In one embodiment of the present invention, the smelting equipment is evacuated, and when the vacuum degree reaches 5×10 ^-3 Pa, the smelting equipment is filled with argon at about half an atmosphere; then the process is repeated again, So that the smelting process is performed under an inert atmosphere such as argon.

Optionally, in the step (2), after the simple metal raw material is melted into an alloy liquid, the alloy liquid is stirred at a constant temperature. For example, when a non-consumable vacuum arc furnace is used for smelting, the arc current is adjusted to heat and melt the elemental metal raw materials to form an alloy liquid, and then the arc is maintained for 60-120 seconds and cooled to obtain an alloy ingot. Through this constant temperature stirring process, the metal elemental raw materials can be better mixed uniformly.

In the present invention, in the step (2), the smelting temperature can be, but not limited to, 400-500°C higher than the highest melting point metal element raw material. Optionally, the melting temperature may be, but is not limited to, 2000-2400°C.

Optionally, in the step (3), in the fixed mold forming process, the alloy after smelting the elemental metal raw materials uniformly can be sucked and casted into a mold through a vacuum suction casting device. Through the vacuum suction casting equipment, the alloy is effectively prevented from being contaminated by impurities during the cooling and forming process.

Optionally, according to the size and shape of the desired product, the alloy can be suction cast into molds of different sizes or shapes. Optionally. The mold can be, but is not limited to, a water-cooled copper mold.

Optionally, the crystal structure of the high-entropy alloy resistant to corrosion by marine microorganisms is a face-centered cubic structure.

In one embodiment of the present invention, the alloy is suction cast into a water-cooled copper mold to obtain a cylindrical sample of a high-entropy alloy resistant to marine microbial corrosion with a diameter (Φ) of 10 mm.

In the third aspect, the present invention also provides a marine microbial corrosion resistant high-entropy alloy containing the marine microbial corrosion resistant high-entropy alloy according to the first aspect of the present invention or the marine microbial corrosion resistant high-entropy alloy produced by the preparation method according to the second aspect of the present invention. Application in marine engineering equipment. In one embodiment, the high-entropy alloy resistant to marine microbial corrosion can be, but not limited to, used for components that are in direct contact with seawater. Since the high-entropy alloy resistant to marine microbial corrosion has strong resistance to marine microbial corrosion, it can effectively protect the equipment and prolong the service life of the equipment when it is used in parts such as equipment shells.

Optionally, the marine engineering equipment may include, but is not limited to, seawater pipelines, pump valves, heat exchangers or brackets. The marine engineering equipment may also be other marine underwater equipment.

Beneficial effect

The beneficial effects of the present invention include the following aspects:

(1) The high-entropy alloy resistant to marine microbial corrosion of the present invention is a six-element alloy containing Al, Co, Cr, Fe, Ni and Cu, and the general chemical formula is Al _0.1 CoCrFeNiCu _x , where 0.3≤x≤0.5, which The crystal structure is a face-centered cubic structure. The high-entropy alloy material maintains the material's good corrosion resistance and has excellent marine microbial corrosion resistance.

(2) The preparation method of the marine microbial corrosion-resistant high-entropy alloy of the present invention has a simple process and is easy to realize industrialized production. The prepared high-entropy alloy material has a uniform mixture of metal elementary raw materials and has excellent resistance to marine microbial corrosion. Performance; At the same time, the high-entropy alloy resistant to marine microbial corrosion of the present invention is obtained by smelting ordinary pure metal elemental raw materials, has low preparation cost, can protect equipment from corrosion in the marine environment, and has a good application prospect in marine engineering structural components .

The advantages of the present invention will be partially clarified in the following description, and part of it is obvious from the description, or can be learned through the implementation of the embodiments of the present invention.

Description of the drawings

In order to explain the content of the present invention more clearly, it will be described in detail below with reference to the accompanying drawings and specific embodiments.

FIG. 1 is a process flow diagram of a method for preparing a high-entropy alloy resistant to marine microbial corrosion according to an embodiment of the present invention;

FIG. 2 is a material characterization diagram of a high-entropy alloy resistant to marine microbial corrosion provided by an embodiment of the present invention, wherein (a) in FIG. 2 is an X-ray diffraction pattern; FIG. 2 (b) is a secondary electron microscope image.

Figure 3 is a data diagram of the plate coating results after 24 hours of co-cultivation of different alloys and Pseudomonas aeruginosa according to an embodiment of the present invention; among them, Figure 3 (a) is 316L stainless steel, and Figure 3 (b) is Al-Co-Cr-Fe-Ni high-entropy alloy, Figure 3 (c) is a high-entropy alloy resistant to marine microbial corrosion, Figure 3 (d) is a histogram of antibacterial rate;

4 is an electrochemical potential polarization curve of a high-entropy alloy resistant to marine microbial corrosion and 316L stainless steel provided by an embodiment of the present invention.

Embodiments of the present invention

The following are preferred implementations of the embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the embodiments of the present invention, several improvements and modifications can be made. These improvements And retouching is also regarded as the protection scope of the embodiments of the present invention.

The following further describes the embodiments of the present invention in multiple embodiments. Among them, the embodiments of the present invention are not limited to the following specific embodiments. Within the scope of the unchanging main rights, changes can be appropriately implemented.

Unless otherwise specified, the raw materials and other chemical reagents used in the embodiments of the present invention are all commercially available products.

Referring to Fig. 1, an embodiment of the present invention provides a method for preparing a high-entropy alloy resistant to marine microbial corrosion, including:

S10. After surface pretreatment of Al, Co, Cr, Fe, Ni and Cu metal elementary raw materials, the mole fraction ratio of 0.1:1:1:1:1:x is added to the smelting equipment, where 0.3≤x≤ 0.5;

S20: First, melt the elemental metal raw materials into an alloy liquid under an inert atmosphere, obtain an alloy ingot after cooling, and turn the alloy ingot over four times;

S30. Repeat the step S20 at least twice, and after the simple metal raw materials are uniformly smelted, a fixed mold is formed to obtain a high-entropy alloy resistant to marine microbial corrosion.

Wherein, in the step S10, the surface pretreatment process includes: removing the surface oxide scale of the simple metal raw materials of Al, Co, Cr, Fe, Ni, and Cu, and then performing ultrasonic cleaning and drying. Wherein, it is possible but not limited to use sandpaper or a grinder to remove the surface oxide scale of the metal elementary raw material. Optionally, the ultrasonic cleaning process can be performed but not limited to in absolute ethanol.

Optionally, the smelting equipment is a non-consumable vacuum electric arc furnace; before the smelting equipment smelts the high-entropy alloy resistant to marine microbial corrosion, metallic titanium is smelted to remove impurities in the smelting equipment. By smelting titanium metal first, the free oxygen, nitrogen and other impurities contained in the smelting equipment can be effectively absorbed.

In the step S20, the smelting equipment may be vacuumed at least once to realize the inert atmosphere. Each time the vacuuming process includes vacuuming the melting equipment first, and then introducing inert gas; wherein, the inert gas includes argon.

In one embodiment of the present invention, the smelting equipment is evacuated, and when the vacuum degree reaches 5×10 ^-3 Pa, the smelting equipment is filled with argon at about half an atmosphere; then the process is repeated again, So that the smelting process is performed under an inert atmosphere such as argon.

In the step S20, after the simple metal raw material is melted into an alloy liquid, the alloy liquid is stirred at a constant temperature. For example, when a non-consumable vacuum arc furnace is used for smelting, the arc current is adjusted to heat and melt the elemental metal raw materials to form an alloy liquid, and then the arc is maintained for 60-120 seconds and cooled to obtain an alloy ingot. Through this constant temperature stirring process, the metal elemental raw materials can be better mixed uniformly.

In the step S20, the smelting temperature can be, but not limited to, 400-500°C higher than the highest melting point metal element raw material. Optionally, the melting temperature may be, but is not limited to, 2000-2400°C.

In the step S30, the fixed mold forming process may use a vacuum suction casting device to suck the alloy after the metal elementary raw materials are uniformly smelted into a mold for forming. Through the vacuum suction casting equipment, the alloy is effectively prevented from being contaminated by impurities during the cooling and forming process. For example, the high-entropy alloy reacts with oxygen or nitrogen in the air.

Optionally, according to the size and shape of the desired product, the alloy can be suction cast into molds of different sizes or shapes. Optionally. The mold can be, but is not limited to, a water-cooled copper mold.

The crystal structure of the marine microbial corrosion-resistant high-entropy alloy prepared by the preparation method provided in the embodiment of the present invention is a face-centered cubic structure.

The following further describes the embodiments of the present invention in multiple embodiments.

Example 1

A preparation method of a high-entropy alloy resistant to marine microbial corrosion, including:

The raw materials used for alloy smelting are high-purity (≥99.9%) Al, Co, Cr, Fe, Ni, and Cu elemental raw materials, and sandpaper is used to remove the surface oxide scale of the raw materials Al, Co, Cr, Fe, Ni and Cu, and used in industry Ethanol ultrasonic vibration cleaning, after drying; after peeling and cleaning Al, Co, Cr, Fe, Ni and Cu elemental raw materials, according to the expression Al _0.1 CoCrFeNiCu _0.5 molar ratio for accurate weighing and proportioning, and then added to The non-consumable vacuum arc furnace is used for smelting alloys;

The raw materials are stacked in a non-consumable vacuum arc furnace in order of melting point for smelting. Al and Cu are placed at the bottom, Co, Fe, and Ni are placed in the middle, and Cr has the highest melting point and placed on the top. Then vacuumize, when the vacuum degree reaches 5×10 ^-3 Pa, fill the furnace cavity with argon to half the atmospheric pressure; then vacuumize again to 5×10 ^-3 Pa, and then fill the furnace cavity with argon to half Start smelting the alloy; before smelting the alloy, smelt the titanium ingot, and wait until the titanium ingot is smelted. After melting the Al, Co, Cr, Fe, Ni and Cu alloys, the arc holding time is 60-120 seconds. After the alloy block is cooled, turn it over and repeat at least 4 times; then, repeat the above melting alloy process twice , After making the alloy fully smelted uniformly.

Using vacuum suction casting equipment, the alloy is suction-cast into a water-cooled copper mold to obtain a Φ10mm high-entropy alloy cylindrical sample resistant to marine microbial corrosion, wherein the crystal structure of the prepared high-entropy alloy is a face-centered cubic structure.

Example 2

A preparation method of a high-entropy alloy resistant to marine microbial corrosion, including:

The raw materials used for alloy smelting are high-purity (≥99.95%) Al, Co, Cr, Fe, Ni and Cu elementary raw materials. The surface oxide scale of the raw materials Al, Co, Cr, Fe, Ni and Cu is removed by a grinder, and used together Industrial ethanol ultrasonic vibration cleaning, after drying; after peeling and cleaning Al, Co, Cr, Fe, Ni and Cu elementary raw materials, according to the expression Al _0.1 CoCrFeNiCu _0.4 molar ratio for accurate weighing and proportioning, and then add To the non-consumable vacuum arc furnace for alloy smelting;

The raw materials are stacked in a non-consumable vacuum arc furnace in order of melting point for smelting. Al and Cu are placed at the bottom, Co, Fe, and Ni are placed in the middle, and Cr has the highest melting point and placed on the top. Then vacuumize, when the vacuum degree reaches 5×10 ^-3 Pa, fill the furnace cavity with argon to half the atmospheric pressure; then vacuumize again to 5×10 ^-3 Pa, and then fill the furnace cavity with argon to half Start smelting the alloy; before smelting the alloy, smelt the titanium ingot, and wait until the titanium ingot is smelted. After melting the Al, Co, Cr, Fe, Ni and Cu alloys, the arc holding time is 60-120 seconds. After the alloy block is cooled, turn it over and repeat at least 4 times; then, repeat the above melting alloy process twice , After making the alloy fully smelted evenly.

Using vacuum suction casting equipment, the alloy is suction-cast into a water-cooled copper mold to obtain a Φ10mm high-entropy alloy cylindrical sample resistant to marine microbial corrosion, wherein the crystal structure of the prepared high-entropy alloy is a face-centered cubic structure.

Example 3

A preparation method of a high-entropy alloy resistant to marine microbial corrosion, including:

The raw materials used for alloy smelting are high-purity (≥99.9%) Al, Co, Cr, Fe, Ni, and Cu elementary raw materials. The surface oxide scale of the raw materials Al, Co, Cr, Fe, Ni, and Cu is removed by using a grinder and used together. Industrial ethanol ultrasonic vibration cleaning, after drying; after peeling and cleaning Al, Co, Cr, Fe, Ni and Cu elemental raw materials, according to the expression Al _0.1 CoCrFeNiCu _0.3 molar ratio for accurate weighing and proportioning, and then add To the non-consumable vacuum arc furnace for alloy smelting;

The raw materials are stacked in a non-consumable vacuum arc furnace in order of melting point for smelting. Al and Cu are placed at the bottom, Co, Fe, and Ni are placed in the middle, and Cr has the highest melting point and placed on the top. Then evacuate, when the vacuum degree reaches 5×10 ^-3 Pa, fill the furnace cavity with argon to half an atmosphere; then evacuate again to 5×10 ^-3 Pa, and then fill the furnace cavity with argon to half Start smelting the alloy; before smelting the alloy, smelt the titanium ingot, and wait until the titanium ingot is smelted. After melting the Al, Co, Cr, Fe, Ni and Cu alloys, the arc holding time is 60-120 seconds. After the alloy block is cooled, turn it over and repeat at least 4 times; then, repeat the above melting alloy process twice , After making the alloy fully smelted uniformly.

Using vacuum suction casting equipment, the alloy is suction-cast into a water-cooled copper mold to obtain a Φ10mm high-entropy alloy cylindrical sample resistant to marine microbial corrosion, wherein the crystal structure of the prepared high-entropy alloy is a face-centered cubic structure.

Example of effects

(1) Material characterization of high-entropy alloy resistant to marine microbial corrosion

X-ray diffraction (XRD) was performed on the high-entropy alloy resistant to marine microbial corrosion by the preparation method described in Example 1, and scanning electron microscope imaging was performed. The detection results are shown in FIG. 2.

As shown in Figure 2 (a), the high-entropy alloy resistant to marine microbial corrosion produced by the present invention has the XRD peak position basically coincides with the theoretical element peak position, and no miscellaneous peaks appear. At the same time, the XRD yields The peak position can also prove that the high-entropy alloy prepared in Example 1 of the present invention has a face-centered cubic crystal structure. In the secondary electron microscope picture shown in Figure 2(b), it can be seen that the surface is very clean and the texture is uniform, indicating that the microstructure is a single solid solution structure.

(2) Determination of antibacterial properties of high-entropy alloys resistant to marine microbial corrosion

According to "JIS Z 2801-2000 "Antibacterial Processing Products-Antibacterial Property Test Method and Antibacterial Effect", GB/T 2591-2003 "Antibacterial Plastic Antibacterial Property Test Method and Antibacterial Effect"" and other standards, the marine microbial corrosion resistance is carried out. High-entropy alloy (experimental group), 316L stainless steel (control group 1) and Al-Co-Cr-Fe-Ni high-entropy alloy (control group 2) have their effects on typical bacteria (Pseudomonas aeruginosa) in the ocean. Bacteria) antibacterial performance test, where: bactericidal rate (%) = [(number of viable bacteria in the control group-number of viable bacteria in the experimental group)/number of viable bacteria in the control group]×100, the results are shown in Figure 3.

Among them, the number of viable bacteria in the control group refers to the number of viable bacteria in the control group 1 or 2 after co-cultivation with Pseudomonas aeruginosa, and the experimental group is co-cultured with Pseudomonas aeruginosa and high-entropy alloy resistant to marine microbial corrosion. After the number of viable cells; the molar ratio of each element in the Al-Co-Cr-Fe-Ni high-entropy alloy is Al:Co:Cr:Fe:Ni=0.1:1:1:1:1.

Figure 3 (a) is the result of plate coating after 24 hours of co-cultivation of 316L stainless steel and Pseudomonas aeruginosa (control 1), and Figure 3 (b) is the Al-Co-Cr-Fe-Ni high-entropy alloy Plate coating results after 24 hours of co-cultivation with Pseudomonas aeruginosa (control group 2), Figure 3 (c) is the high-entropy alloy A resistant to marine microbial corrosion of the present invention and Pseudomonas aeruginosa co-cultured for 24 hours After the flat coating results (experimental group). It can be seen from the number of colonies on the plate that the high-entropy alloy resistant to marine microbial corrosion of the present invention has a high ability to inhibit the growth of Pseudomonas aeruginosa; while conventional 316L stainless steel and conventional Al-Co-Cr- Fe-Ni high-entropy alloy has poor ability to inhibit the growth of Pseudomonas aeruginosa. Refer to Figure 3(d) for the bar graph of antibacterial rate calculated based on the result of flat coating. The results show that with 316L stainless steel as control group 1, and Al-Co-Cr-Fe-Ni high-entropy alloy as control group 2, the antibacterial rate of experimental group A of the high-entropy alloy resistant to marine microbial corrosion in the present invention reached 99% Above, it shows excellent antibacterial performance.

Therefore, compared with conventional high-entropy alloys and stainless steel materials, the high-entropy alloys containing marine microbial corrosion resistance provided by the present invention have more excellent antibacterial properties.

(3) Determination of corrosion resistance of high-entropy alloys resistant to marine microbial corrosion

The electrochemical potentiodynamic polarization curves of the marine microbial corrosion resistant high-entropy alloy and 316L stainless steel samples co-cultured with Pseudomonas aeruginosa for 24 hours were measured respectively. The potential is relative to the electrode of the saturated calomel electrode (vs. SCE) Electric potential, see Figure 4 for the results. It can be seen from the relationship between the potential and the current in the polarization curve in the figure that the corrosion potential of the high-entropy alloy resistant to marine microbial corrosion of the present invention is about -0.2V, while the corrosion potential of 316L stainless steel is about -0.45V; and The pitting corrosion potential of the high-entropy alloy resistant to marine microbial corrosion is higher than that of 316L; therefore, it can be seen by comparison that the uniform corrosion resistance and local corrosion resistance of the high-entropy alloy resistant to marine microbial corrosion of the present invention are better than that of 316L Stainless steel reflects that the high-entropy alloy resistant to marine microbial corrosion of the present invention has excellent anti-microbial corrosion performance.

The mole fraction ratio of the elements of the high-entropy alloy resistant to marine microbial corrosion in the embodiment of the present invention is Al:Co:Cr:Fe:Ni:Cu=0.1:1:1:1:1:x, 0.3≤x ≤0.5; on the one hand, the high-entropy alloy within this ratio range can significantly inhibit the growth of microorganisms on its surface and has excellent corrosion resistance against marine microorganisms. On the other hand, the high-entropy alloy also has stable performance Strengthened, and the crystal structure is a face-centered cubic structure. For example, when the mole fraction of Cu is lower than the ratio range, the antibacterial rate is poor; when the mole fraction of Cu is higher than the ratio range, the high-entropy alloy is prone to second phase precipitation and strong selective corrosion. Cause the corrosion resistance of the material to decrease.

The above-mentioned embodiments only express several implementation modes of the present invention, and their description is relatively specific and detailed, but they should not be understood as a limitation on the patent scope of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all fall within the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims (10)

1. A high-entropy alloy resistant to marine microbial corrosion, characterized in that the general chemical formula of the high-entropy alloy resistant to marine microbial corrosion is Al _0.1 CoCrFeNiCu _x , where x is the mole fraction of Cu, 0.3≤x≤0.5.
2. The high-entropy alloy resistant to marine microbial corrosion according to claim 1, wherein the crystal structure of the high-entropy alloy resistant to marine microbial corrosion is a face-centered cubic structure.
3. The high-entropy alloy resistant to marine microbial corrosion according to claim 1, wherein in the general chemical formula, 0.45≤x≤0.5.
4. The high-entropy alloy resistant to marine microbial corrosion according to claim 1, wherein the antibacterial rate of the high-entropy alloy resistant to marine microbial corrosion reaches more than 90%.
5. The marine microbial corrosion resistant high-entropy alloy according to claim 1, wherein the purity of Al, Co, Cr, Fe, Ni, and Cu in the marine microbial corrosion resistant high-entropy alloy is greater than 99.9%.
6. A preparation method of a high-entropy alloy resistant to marine microbial corrosion, which is characterized in that it comprises:

   (1) After surface pretreatment of Al, Co, Cr, Fe, Ni and Cu metal elementary raw materials, the mole fraction ratio of 0.1:1:1:1:1:x is added to the smelting equipment, where 0.3≤x ≤0.5;

   (2) First, melt the elemental metal raw materials into an alloy liquid under an inert atmosphere, obtain an alloy ingot after cooling, and turn the alloy ingot over four times;

   (3) Repeat the step (2) at least twice, and after the elemental metal raw materials are evenly smelted, they are molded into a fixed mold to obtain a high-entropy alloy resistant to marine microbial corrosion.
7. The preparation method according to claim 6, wherein the metal elemental raw materials of Al, Co, Cr, Fe, Ni, and Cu are stacked in the smelting equipment in order of melting point from small to large; The purity of the simple metal raw materials of Al, Co, Cr, Fe, Ni and Cu are all greater than 99.9%.
8. 7. The preparation method of claim 6, wherein the crystal structure of the high-entropy alloy resistant to marine microbial corrosion is a face-centered cubic structure.
9. The preparation method of claim 6, wherein the smelting equipment is a non-consumable vacuum electric arc furnace; before the smelting equipment smelts the high-entropy alloy resistant to marine microbial corrosion, the metal titanium is smelted to remove all the alloys. Describe the impurities in the smelting equipment.
10. The high-entropy alloy resistant to marine microbial corrosion according to any one of claims 1 to 5 or the high-entropy resistant alloy resistant to marine microbial corrosion produced by the preparation method according to any one of claims 6-9 is used in marine engineering equipment. application.