WO2023078011A1 - Refractory high-entropy amorphous alloy material, preparation method therefor and use thereof - Google Patents

Abstract

Disclosed is a refractory high-entropy amorphous alloy material, comprising three or more refractory metal elements among Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W and Re, and one or two non-refractory metal elements among Al, Si, Co, B and Ni, the refractory high-entropy amorphous alloy material having an amorphous structure. The refractory high-entropy amorphous alloy material has high corrosion resistance and mechanical performance. Further disclosed is a preparation method for said refractory high-entropy amorphous alloy material, which comprises: performing batching according to the atomic fractions of the respective elements of a refractory high-entropy amorphous alloy material, and uniformly smelting to obtain a master alloy ingot; and after melting the mother alloy ingot, spraying same onto the surface of a rotating copper roller to obtain a refractory high-entropy amorphous alloy strip. The method is simple and efficient, and may be used in large-scale industrial production. Also disclosed is a use of the refractory high-entropy amorphous alloy material in pipe transportation in nuclear reactors and nuclear power and corrosion environments.

Description

A kind of refractory high-entropy amorphous alloy material and its preparation method and application technical field

The invention belongs to the field of corrosion and material science, and in particular relates to a refractory high-entropy amorphous alloy material and its preparation method and application.

Background technique

Refractory metal alloys were originally composed of five refractory elements, Mo (molybdenum), Nb (niobium), Ta (tantalum), W (tungsten) and vanadium (V), and then expanded to include subgroup IV ( Ti, Zr, Hf), V subgroups (V, Nb, Ta), VI subgroups (Cr, Mo, W) and Re, 10 metal elements with a melting point higher than 1800°C and certain reserves, and non-refractory elements , such as Al, Si, Co and Ni composition. In 2004, Professor Ye Junwei proposed the concept of high-entropy alloys. Combining the concepts of refractory metals and high-entropy alloys, refractory high-entropy alloys were first reported in 2010. The definition of refractory high-entropy alloys is extended to contain 3 or more major elements and the atomic fraction of elements is greater than 35%. Refractory high-entropy alloys have high temperature resistance, wear resistance, corrosion resistance and radiation resistance and excellent mechanical properties at high temperatures.

Amorphous alloys, also known as "metallic glasses", were proposed by Professor Duwez in the 1960s. The atomic structure of amorphous alloys is in a state of short-range order and long-range disorder, so it has a series of mechanical, physical and chemical properties that are significantly superior to traditional crystalline alloys. Such as high strength, high elasticity, high toughness and excellent corrosion resistance, so it has broad application prospects in the fields of machinery, energy, chemical industry and military affairs.

The concept of high-entropy amorphous alloys was first proposed by Academician Wang Weihua's research group in 2011. Combining the concepts of high-entropy alloys and amorphous alloys, the concept of high-entropy alloy composition design was applied to the design and development of traditional amorphous alloys. Alloys have high mixing entropy, excellent mechanical properties, corrosion resistance and other functional properties.

At present, nickel-based superalloys are widely used as high-temperature parts of aero-engines, heat exchanger piping, and high-temperature alloy parts in chemical processing. However, the melting point of nickel-based superalloys is low, and they do not meet the requirements for use under relatively severe working conditions. Refractory high-entropy alloys, which are expected to be substitutes for nickel-based superalloys, have excellent properties at high temperatures, but refractory high-entropy alloys have the disadvantages of poor high-temperature oxidation resistance, poor ductility at room temperature, and high density, making them a breakthrough in nickel-based high-entropy alloys. There are many difficulties in developing alternatives to base superalloys.

Therefore, the development of a material with excellent properties of high-entropy alloys, refractory alloys and amorphous alloys is critical to its preparation method and application. The size difference between them is large and it is easy to cause lattice distortion, and it is not easy to form amorphous alloys, so that it is more difficult to prepare refractory high-entropy amorphous alloys.

Contents of the invention

The invention provides a refractory high-entropy amorphous alloy material, which has high corrosion resistance and high mechanical performance.

A refractory high-entropy amorphous alloy material includes refractory metal elements: more than three of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Re, and non-refractory metal elements: Al, Si , Co, B, Ni or one or both, and the refractory high-entropy amorphous alloy material has an amorphous structure.

In the present invention, the refractory high-entropy alloy material is combined with the amorphous structure to form the refractory high-entropy amorphous alloy material. The refractory high-entropy amorphous alloy material has a natural amorphous oxide layer, and the components are evenly distributed, thereby having both The characteristics of refractory high-entropy alloy materials and amorphous materials have high corrosion resistance and mechanical properties.

Add a certain amount of non-refractory elements that easily form eutectic points with refractory elements on the basis of ensuring that the system is a refractory high-entropy alloy to enhance the amorphous forming ability of the material system.

The chemical formula of the refractory high-entropy amorphous alloy material is recorded as Hf _a Ta _b Nb _{c Red} Ti _e Zr _f V _g Cr _h Mo _i W _j R _k , wherein R is selected from non-refractory elements Al, Si, One or two elements of Co, B and Ni, and a, b, c, d, e, f, g, h, i, j, k represent the atomic fraction respectively, a, b, c, d, e , f, g, h, i, j, k are all 5-25 and a+b+c+d+e+f+g+h+i+j+k=100.

When the atomic fraction is not expressed, the refractory high-entropy amorphous alloy material is represented by Hf-Ta-Nb-Re-Ti-Zr-V-Cr-Mo-W-R.

The atomic fractions of the refractory metal elements are respectively: the atomic fraction of Hf is 10%-25%, the atomic fraction of Ta is 10%-25%, the atomic fraction of Nb is 10%-25%, and the atomic fraction of Re is 5%- 25%, Ti atomic fraction 10%-25%, Zr atomic fraction 10%-25%, V atomic fraction 10%-25%, Cr atomic fraction 10%-25%; Mo atomic fraction 5%- 25%, W atomic fraction is 5%-25%.

In the refractory high-entropy amorphous alloy material, refractory elements account for the main atomic fraction, and the atomic fraction is greater than 35%. Fusible high-entropy amorphous alloy material, which has both the excellent high-temperature performance of refractory high-entropy alloys and the excellent mechanical properties of amorphous alloys at room temperature.

The atomic fractions of the non-refractory metal elements are respectively: the atomic fraction of Ni is 10%-25%, the atomic fraction of Co is 10%-25%, the atomic fraction of Al is 5%-25%, and the atomic fraction of Si is 5%-25%. 25%, B atomic fraction is 5%-10%.

The present invention also provides the preparation method of the refractory high-entropy amorphous alloy material, comprising:

(1) batching is carried out according to the atomic fraction of each element of the refractory high-entropy amorphous alloy material, and the smelting is uniform to make a master alloy ingot;

(2) The master alloy ingot is melted and then sprayed onto the surface of a rotating copper roll to obtain a refractory high-entropy amorphous alloy strip.

The present invention selects refractory and non-refractory metal elements that are easy to form eutectic points, and rapidly cools to form an amorphous structure in the copper roller rapid quenching technology, so that the arrangement of metal atoms is disordered, and the grain boundaries of crystalline metals are eliminated. Dislocations, segregation and other local inhomogeneous defects, so that the refractory high-entropy amorphous alloy strips have better mechanical properties and corrosion resistance.

In step (1):

Further, the elements and atomic fractions of the refractory high-entropy amorphous alloy material are: the atomic fraction of Hf is 19%-20%, the atomic fraction of Ni is 19%-20%, and the atomic fraction of Ta is 19%-20%. , Co atomic fraction is 19%-20%, Nb atomic fraction is 19%-20%, V atomic fraction is 19%-20%, Re atomic fraction is 5%-7%, B atomic fraction is 5%-7% , W atomic fraction is 5%-7%, Al atomic fraction is 5%-7%, Mo atomic fraction is 5%-7%, Si atomic fraction is 5%-7%.

Before the smelting is uniform, each element of the refractory high-entropy amorphous alloy material is ultrasonically cleaned and sanded.

Further, the steps of ultrasonic cleaning and sanding include: ultrasonic cleaning with alcohol or acetone for 10-20 minutes, repeated cleaning twice, and then ultrasonic cleaning with alcohol or acetone for 10-20 minutes after sanding.

Since the surface of metal elements is easily oxidized, which affects the purity of the alloy, it is necessary to remove the oxide skin on the surface of the raw material particles before smelting until the metal's own luster is exposed.

The smelting step is as follows: arc smelting for 3-4 minutes at a vacuum degree of 4.0×10 ^-3 -5.0×10 ^-3 Pa, and a current of 80-360A.

Repeat the smelting of each element of the refractory high-entropy amorphous alloy material for more than 5 times. To ensure the uniformity of the composition of the master alloy ingot.

The density of said master alloy ingot is ≤13.0g/cm ³ .

Existing refractory alloys have a relatively high density, which does not meet the design requirements of lightweight products. However, the refractory high-entropy amorphous alloy material provided by the present invention has a density lower than that of the prior art refractory materials and has better lightweight characteristics.

In step (2):

The melted master alloy ingot is sprayed onto the surface of the copper roller at a vacuum degree below 10 Pa, and the linear velocity of the surface of the copper roller is greater than 20 m/s.

A high line speed on the surface of the copper roll will cause poor forming quality of the material, and a lower line speed means a low cooling rate, which will cause the material to fail to form an amorphous structure. Due to the high melting point of refractory metals, the viscosity of the material system is high, the fluidity is not good, the large size difference between atoms is likely to cause lattice distortion, and the ability to form amorphous is very poor. The selection of the material system is particularly critical in the material preparation process. . In order to form a well-formed amorphous refractory high-entropy amorphous material, the surface line speed of the copper roll is required to be greater than 20m/s, and the alloy system needs to have good amorphous forming ability.

The thickness of the refractory high-entropy amorphous alloy strip is 20-60 μm, and the width is 0.5-3 mm.

The invention uses a vacuum belt throwing machine to prepare amorphous materials. In addition to all the characteristics of an induction melting furnace, the equipment also has the function of preparing bulk amorphous and thin metal strips by spray casting. In order to maximize the amorphization of the alloy and obtain a refractory high-entropy amorphous alloy ribbon with a completely amorphous structure, the Hf-Ta-Nb-Re-Ti was prepared by a rapid cooling vacuum single-roll spin quenching strip technology. -Zr-V-Cr-Mo-W-R refractory high-entropy amorphous alloy ribbon.

The application of the refractory high-entropy amorphous alloy material to nuclear reactors and nuclear power in high-temperature or marine environments, as well as applications in pipeline transportation in corrosive environments.

Compared with prior art, the beneficial effect of the present invention is:

1. The present invention provides a kind of preparation method of refractory high-entropy amorphous alloy material, utilizes single-roll quick quenching method to carry out rapid cooling to form refractory high-entropy amorphous alloy material with high eutectic degree refractory alloy, this method Simple and efficient.

2. The structure of the refractory high-entropy amorphous alloy material obtained in the present invention is a completely amorphous structure, and the composition has the common effect of the refractory high-entropy alloy and the amorphous alloy material. The constituent elements of the refractory high-entropy amorphous alloy material provided by the present invention have both equiatomic ratio design and non-equioatomic ratio design, which can increase the atomic radius difference of the alloy while maintaining its high mixing entropy, and improve the Amorphous forming ability.

Description of drawings

Fig. 1 is the XRD pattern of the refractory high-entropy amorphous alloy strip prepared in Examples 1, 2 and 3 of the present invention, wherein, Fig. 1 (a) is the XRD pattern of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ , Fig. 1(b) is the XRD pattern of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , and Fig. 1(c) is the XRD pattern of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ .

Fig. 2 is the DSC curve of the refractory high-entropy amorphous alloy strip prepared by Examples 1, 2 and 3 of the present invention, wherein, Fig. 2 (a) is the DSC curve of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ , Fig. 2(b) is the DSC curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , and Fig _. 2(c) is the DSC curve of Hf ₁₉ Ni ₁₉ Ta 19 Co ₁₉ Nb ₁₉ B ₅ .

Fig. 3 is the relationship curve between depth and strength in the nanoindentation experiment of the refractory high-entropy amorphous alloy strips prepared in Examples 1, 2 and 3 of the present invention, wherein Fig. 3(a) is Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ relationship curve, Figure 3(b) is the relationship curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , Figure 3(c) is the relationship curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ Graph.

Fig. 4 is the relationship curve between depth and modulus in the nanoindentation experiment of the refractory high-entropy amorphous alloy strips prepared in Examples 1, 2 and 3 of the present invention, wherein Fig. 4(a) is Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ relationship curve, Figure 4(b) is the relationship curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , Figure 4(c) is the relationship curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ Relationship graph.

Figure 5 is the stress-strain tensile curves of the refractory high-entropy amorphous alloys prepared in Examples 1, 2 and 3 of the present invention, wherein Figure 5(a) is the tensile curve of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ Figure 5(b) is the tensile curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , and Figure 5(c) is the tensile curve of Hf ₁₉ Ni ₁₉ Ta 19 Co _{19 Nb 19 B 5} .

Figure 6 is the potentiodynamic polarization curve obtained after electrochemical testing of the refractory high-entropy amorphous alloy strips prepared in Examples 1, 2 and 3 of the present invention, wherein Figure 6(a) is Hf ₂₀ Ni ₂₀ Ta ₂₀ The polarization curve of Co ₂₀ Nb ₂₀ , Figure 6(b) is the polarization curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , Figure 6(c) is the polarization curve of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ The polarization curve diagram.

Fig. 7 is a transmission electron microscope high-resolution image of the passivation film formed on the refractory high-entropy amorphous alloy strip prepared in Example 1 of the present invention after electrochemical constant potential 1V test for 60 minutes.

Detailed ways

In view of the defects of the prior art, the inventor of this case has been able to propose the technical solution of the present invention through long-term research and extensive practice. The technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are a part of the present invention Examples, not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The used Hf, Ta, Nb, Re, Ni, Co, Ti, Zr, V, Cr, Mo, W, Al, Si and B particles or bulk raw materials used in the preparation of alloy ingots in the present invention are all commercially available raw materials with a purity higher than 99.9%.

The electric arc smelting furnace used in the present invention is the DHL-300 vacuum copper mold suction casting smelting system developed by Shenyang Scientific Instrument Co., Ltd., Chinese Academy of Sciences.

The vacuum belt throwing machine used in the present invention is a VF-RQB20 type single-roller rotary quenching casting equipment.

Example 1

Preparation and property test of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ refractory high-entropy amorphous alloy material.

According to the atomic fraction of the refractory high-entropy amorphous alloy material converted into mass percentage and weighed, select high-purity Hf particles, Ni particles, Ta blocks, Co blocks, Nb particles (purity not less than 99.9%) as raw materials, and polish the scale Afterwards, ultrasonic cleaning was performed twice for 10 min with alcohol. The mass of the smelted alloy ingot is 19.930g, and the mass of each element is w(Hf)=6.241g, w(Ni)=2.052g, w(Ta)=6.327g, w(Co)=2.061g, w(Nb)= 3.249g.

The master alloy ingot was prepared by arc melting method under the protective atmosphere of vacuum and argon, repeated vacuum washing three times to a vacuum degree of 5 × ^10-3 Pa, and high-purity argon gas with a purity of 99.999% was injected until the pressure of the vacuum chamber was -0.05MPa, mixed evenly and smelted in the argon gas atmosphere chamber adsorbed by titanium, in which the smelting process needs to be smelted five times repeatedly to ensure the uniformity of the alloy ingot composition, and Hf-Ni-Ta-Co-Nb is obtained after cooling The master alloy ingot Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ of the equiatomic ratio quinary alloy; the actual density of the alloy is 11.939g/cm ³ measured by the drainage method through the Mettler electronic analytical balance.

Break the master alloy ingot of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ , take an appropriate amount of master alloy and place it in a quartz tube, and fix the quartz tube in the induction coil. The diameter of the nozzle of the quartz tube is about 1.2mm, and the distance between the nozzle and the copper roller The height is 1.5mm. Pump the vacuum down to below 10Pa, and pour in high-purity argon to keep the air pressure in the chamber of the stripping machine at -0.09MPa, and the pressure difference between the air pressure in the quartz tube and the chamber is maintained at 0.05MPa. Subsequently, the liquid alloy solution was sprayed onto a high-speed rotating copper roll to obtain an alloy strip, wherein the surface speed of the copper roll was 40 m/s. In this embodiment, the width of the strip is about 2 mm, and the thickness of the strip is about 23 μm.

The properties of the as-prepared strips of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ refractory high-entropy amorphous materials were determined.

The X-ray diffraction (XRD) image of the above striped Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ sample is shown in Figure 1(a), which shows a single diffuse scattering peak, proving that the striped sample is completely amorphous state alloy.

Differential scanning calorimetry (DSC) experiments were carried out on the above amorphous alloy strips, and the DSC curve is shown in Figure 2(a), which reflects the glass transition and crystallization process of the refractory high-entropy amorphous alloy, which can be It can be seen that the glass transition temperature T _g of Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ refractory high-entropy amorphous alloy is 827K, and the initial crystallization temperature T _x1 is 883K. After the initial crystallization, there are still two crystallization The crystallization peak, the second crystallization temperature T _x2 is 990K, the third crystallization temperature T _x3 is 1133K, and there is a supercooled liquid phase region ΔT of 56K. It shows that the above-mentioned refractory high-entropy amorphous has a complicated crystallization process, and also has good amorphous forming ability and thermal stability.

Nanoindentation (DSI) experiments were performed on the above refractory high-entropy amorphous alloy strips, the results are shown in Figure 3(a) and Figure 4(a), Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ refractory high-entropy The modulus of the amorphous alloy is 79GPa and the strength is 4.44GPa.

The room temperature tensile test was carried out on _the above-mentioned refractory high-entropy amorphous alloy strips, and _the results _are shown in Figure 5(a _{) .} The modulus is 75GPa, the maximum stress is 1388MPa, the maximum strain is 2.2%, and the load is 38N.

The corrosion resistance of the alloy was tested on the German ZAHNER Zennium electrochemical workstation, in which the corrosion solution was 4mol/L H ₂ SO ₄ solution, the results are shown in Figure 6(a), Hf ₂₀ Ni ₂₀ Ta ₂₀ Co ₂₀ Nb ₂₀ The self-corrosion potential of the refractory high-entropy amorphous alloy is 0.13V, and the self-corrosion current density is 0.796nA/cm ² . Because there is an obvious passivation interval in the polarization curve, the breakdown potential is 1.56V, and the passivation current density is 1.56V. It is 4.288μA/cm ² .

The thickness of the passivation film was characterized by the Tecnai F20 transmission electron microscope of the US FEI company after the electrochemical constant potential corrosion. The results are shown in Figure 7. The base material is an amorphous structure, and the thickness of the passivation film is 8.5nm. , indicating that the material has excellent corrosion resistance.

Example 2

Preparation and property determination of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ refractory high-entropy amorphous alloy material.

According to the atomic fraction of the refractory high-entropy amorphous alloy material converted into mass percentage and weighed, high-purity Hf particles, Ni particles, Ta blocks, Co blocks, Nb particles, Re particles (purity not less than 99.9%) are selected as raw materials, After polishing the scale, ultrasonically clean it twice with alcohol for 10 minutes. The mass of the smelted alloy ingot is 20g, and the mass of each element is w(Hf)=5.767g, w(Ni)=1.896g, w(Ta)=5.847g, w(Co)=1.904g, w(Nb)=3.002 g, w(Re) = 1.583g.

The master alloy ingot was prepared by arc melting method under the protective atmosphere of vacuum and argon, repeated vacuum washing three times to a vacuum degree of 5 × ^10-3 Pa, and high-purity argon gas with a purity of 99.999% was injected until the pressure of the vacuum chamber was -0.05MPa, mixed evenly and smelted in the argon gas atmosphere chamber adsorbed by titanium, in which the smelting process needs to be smelted five times repeatedly to ensure the uniformity of the alloy ingot composition, and Hf-Ni-Ta-Co-Nb is obtained after cooling The master alloy ingot of -Re six-element alloy is Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ ; the actual density of the alloy is 12.26g/cm ³ as measured by the drainage method with a Mettler electronic analytical balance.

Break the master alloy ingot of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ , take an appropriate amount of master alloy and place it in a quartz tube, and fix the quartz tube in the induction coil. The diameter of the nozzle of the quartz tube is about 1.2mm, and the distance between the nozzle and the copper The height of the rollers is 1.5 mm. Pump the vacuum down to below 10Pa, and pour in high-purity argon to keep the air pressure in the chamber of the stripping machine at -0.09MPa, and the pressure difference between the air pressure in the quartz tube and the chamber is maintained at 0.05MPa. Subsequently, the liquid alloy solution was sprayed onto a high-speed rotating copper roll to obtain alloy strips, wherein the surface speed of the copper roll was 40 m/s. In this embodiment, the width of the strip is about 1.5 mm, and the thickness of the strip is about 30 μm.

The properties of the as-prepared strips of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ refractory high-entropy amorphous materials were determined.

The X-ray diffraction (XRD) images of the above striped Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ samples are shown in Figure 1(b), showing a single diffuse scattering peak, which proves that the striped sample is Completely amorphous alloy.

Differential scanning calorimetry (DSC) experiments were carried out on the above-mentioned amorphous alloy strips, and the DSC curve is shown in Figure 2(b), which reflects the glass transition and crystallization process of the refractory high-entropy amorphous alloy, which can be It can be seen that the glass transition temperature T _g of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ refractory high-entropy amorphous alloy is 828K, the initial crystallization temperature T _x1 is 883K, and the second crystallization temperature T _x2 is 980K, the third crystallization temperature is T _x3 is 1035K, there is a supercooled liquid phase region ΔT of 55K. It shows that the above-mentioned refractory high-entropy amorphous has a complicated crystallization process, and also has good amorphous forming ability and thermal stability.

Nanoindentation (DSI) experiments were performed on the above refractory high-entropy amorphous alloy strips, the results are shown in Figure 3(b) and Figure 4(b), Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ Re ₅ refractory The high-entropy amorphous alloy has a modulus of 87GPa and a strength of 4.82GPa.

The above-mentioned refractory high-entropy amorphous alloy strips were subjected to room temperature tensile experiments, and the results are shown in Figure 5(b). The Hf ₁₉ Ni ₁₉ Ta ₁₉ Co 19 Nb _{19 Re 5} refractory high-entropy amorphous The elastic modulus is 34GPa, the maximum stress is 691MPa, the maximum strain is 2.4%, and the load is 27N.

The corrosion resistance of the alloy was tested by ZAHNER Zennium electrochemical workstation in Germany, in which the corrosion solution was 4mol/L H ₂ SO ₄ solution, the results are shown in Figure 6(b), Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ The self-corrosion potential of Re ₅ refractory high-entropy amorphous alloy is 0.12V, and the self-corrosion current density is 0.941nA/cm ² . Because there is an obvious passivation interval in the polarization curve, its breakdown potential is calculated to be 1.55V. The current density was 4.825 μA/cm ² .

Example 3

Preparation and property determination of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ refractory high-entropy amorphous alloy material.

According to the atomic fraction conversion of the refractory high-entropy amorphous alloy material into mass percentage and weighing, select high-purity Hf particles, Ni particles, Ta blocks, Co blocks, Nb particles, B particles (purity not less than 99.9%) as raw materials, After polishing the scale, ultrasonically clean it twice with alcohol for 10 minutes. The mass of the smelted alloy ingot is 20g, and the mass of each element is w(Hf)=6.232g, w(Ni)=2.049g, w(Ta)=6.318g, w(Co)=2.058, w(Nb)=3.244g , w(B)=0.099g.

The master alloy ingot was prepared by arc melting method under the protective atmosphere of vacuum and argon, repeated vacuum washing three times to a vacuum degree of 5 × ^10-3 Pa, and high-purity argon gas with a purity of 99.999% was injected until the pressure of the vacuum chamber was -0.05MPa, mixed evenly and smelted in the argon gas atmosphere chamber adsorbed by titanium, in which the smelting process needs to be smelted five times repeatedly to ensure the uniformity of the alloy ingot composition, and Hf-Ni-Ta-Co-Nb is obtained after cooling The master alloy ingot of -B six-element alloy is Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ ; the actual density of the alloy is 11.97g/cm ³ as measured by the drainage method with a Mettler electronic analytical balance.

Break the master alloy ingot of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ , take an appropriate amount of master alloy and place it in a quartz tube, and fix the quartz tube in the induction coil. The diameter of the nozzle of the quartz tube is about 1.2mm, and the distance between the nozzle and the copper The height of the rollers is 1.5 mm. Pump the vacuum down to below 10Pa, and pour in high-purity argon to keep the air pressure in the chamber of the stripping machine at -0.09MPa, and the pressure difference between the air pressure in the quartz tube and the chamber is maintained at 0.05MPa. Subsequently, the liquid alloy solution was sprayed onto a high-speed rotating copper roll to obtain alloy strips, wherein the surface speed of the copper roll was 40 m/s. In this embodiment, the width of the strip is about 1.4 mm, and the thickness of the strip is about 38 μm.

The properties of the as-prepared strips of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ refractory high-entropy amorphous materials were determined.

The X-ray diffraction (XRD) images of the above striped Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ samples are shown in Figure 1(c), showing a single diffuse scattering peak, which proves that the striped sample is Completely amorphous alloy.

Differential scanning calorimetry (DSC) experiments were carried out on the above-mentioned amorphous alloy strips, and the DSC curve is shown in Figure 2(c), which reflects the glass transition and crystallization process of the refractory high-entropy amorphous alloy, which can be It can be seen that the glass transition temperature T _g of Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ refractory high-entropy amorphous alloy is 828K, the initial crystallization temperature T _x1 is 893K, and the second crystallization temperature T _x2 is 990K, there is a supercooled liquid phase region ΔT of 65K, which shows that the above three refractory high-entropy amorphous crystals have a complex crystallization process, and also have good amorphous forming ability and thermal stability.

Nanoindentation (DSI) experiments were performed on the above refractory high-entropy amorphous alloy strips, the results are shown in Figure 3(c) and Figure 4(c), Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ B ₅ refractory The high-entropy amorphous alloy has a modulus of 91GPa and a strength of 4.36GPa

The above-mentioned refractory high-entropy amorphous alloy strips were subjected to tensile experiments at room temperature, and _the results are shown in Figure 5(c). The Hf ₁₉ Ni ₁₉ Ta 19 Co ₁₉ Nb ₁₉ B ₅ refractory high-entropy amorphous The elastic modulus is 51GPa, the maximum stress is 963MPa, the maximum strain is 2.2%, and the load is 39N.

The corrosion resistance of the alloy was tested on the German ZAHNER Zennium electrochemical workstation, in which the corrosion solution was 4mol/L H ₂ SO ₄ solution, the results are shown in Figure 6(c), Hf ₁₉ Ni ₁₉ Ta ₁₉ Co ₁₉ Nb ₁₉ The self-corrosion potential of _B5 refractory high-entropy amorphous alloy is 0.14V, and the self-corrosion current density is 0.808nA/cm ² . Because there is an obvious passivation interval in the polarization curve, its breakdown potential is calculated to be 1.59V. The current density was 3.96 μA/cm ² .

Embodiment 4～24;

The molecular formulas of the refractory high-entropy amorphous alloys in Examples 4-24 are shown in Table 1 below.

The preparation methods of the refractory high-entropy amorphous alloys in Examples 4-24 are basically the same as those in Examples 1, 2, and 3, except that the ratio of raw materials is compounded according to the molar ratio described in the molecular formula in Table 1.

Similar to Examples 1, 2 and 3, the XRD and DSC patterns of the refractory high-entropy amorphous alloys in Examples 4-24 show that this type of alloy is an amorphous alloy.

Similar to Examples 1, 2 and 3, the electrochemical corrosion experiments of _the refractory high-entropy amorphous alloys in Examples 4-24 were tested respectively, and the corrosion solution was 4mol/L _H2SO4 solution, and each refractory high-entropy amorphous alloy was obtained. The self-corrosion potential and self-corrosion current density of the crystal alloy, because there is an obvious passivation interval in the polarization curve, the breakdown potential and the passivation current density are measured, and the results are shown in Table 1 below.

In addition, compare the corrosion kinetic parameters _of the refractory high-entropy amorphous alloy material prepared in Examples 1 to 24 with common ND steel, B450NS in 0.5mol/L _H2SO4 solution, the test process can refer to the literature (Wu Jinqiang, Chang Zhiping, Yang Mei, et al. Corrosion behavior of ND steel, B450NS in H ₂ SO ₄ solution [J]. Scientific Consulting (Technology·Management), 2014, 06(No.376): 68-69.). Table 1 shows the electrochemical parameters of the refractory high-entropy amorphous alloy materials prepared in Examples 1-24, ND steel and B450NS in 0.5 mol/L H ₂ SO ₄ solution.

Table 1 Electrochemical parameters for polarization curve fitting

Combining Figure 6 and Table 1, it can be seen that the refractory high-entropy amorphous alloy is a passivation material, and its breakdown potential and self-corrosion potential are much higher than those of commonly used ND steel and B450NS, indicating that the newly invented refractory high-entropy Entropic amorphous alloys have more excellent corrosion resistance. Its self-corrosion potential is 3 orders of magnitude higher than that _of ND steel and B450NS used in large-scale engineering equipment, indicating that the refractory high-entropy amorphous alloy in the present invention has a lower corrosion tendency in a higher concentration _H2SO4 solution , the actual corrosion efficiency is smaller, and the corrosion resistance effect is better.

A refractory high-entropy amorphous alloy material of the present invention combines the concepts of amorphous alloys, high-entropy alloys and refractory elements, and proposes the concept of refractory high-entropy amorphous alloys, which greatly improves the refractory high-entropy Entropy alloys have poor mechanical properties at room temperature. The cost of raw materials used in the present invention is moderate, the manufacturing steps are simple and easy, the process is easy to control, and the refractory high-entropy amorphous alloy material with uniform composition, outstanding mechanical properties and excellent corrosion resistance can be obtained, which is conducive to its wide application and large-scale batch production chemical production.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof should not be interpreted as limiting the patent scope of the present invention. It should be noted that, for those skilled in the art, without departing from the concept of the present invention, some modifications and improvements can also be made, and any modification, supplement or improvement made within the scope of the principles of the present invention Substitution by similar methods, etc., all belong to the protection scope of the present invention. Therefore, the scope of protection of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A refractory high-entropy amorphous alloy material is characterized in that it includes refractory metal elements: more than three of Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Re, and non-refractory metals Elements: one or two of Al, Si, Co, B, Ni, wherein the refractory high-entropy amorphous alloy material has an amorphous structure.
2. The refractory high-entropy amorphous alloy material according to claim 1 _, wherein the chemical formula of the refractory high-entropy amorphous alloy material is Hf _a Ta _b Nb _c Red Ti _e Zr _f V _g Cr _h Mo _i W _j R _k , wherein, R is selected from one or two elements of non-refractory elements Al, Si, Co, B or Ni, and a, b, c, d, e, f, g, h, i, j, k represent the atomic fraction respectively, a, b, c, d, e, f, g, h, i, j, k are all 5-25 and a+b+c+d+e+f +g+h+i+j+k=100.
3. The refractory high-entropy amorphous alloy material according to claim 1, wherein the atomic fractions of the refractory metal elements are respectively: the atomic fraction of Hf is 10%-25%, and the atomic fraction of Ta is 10%- 25%, Nb atomic fraction 10%-25%, Re atomic fraction 5%-25%, Ti atomic fraction 10%-25%, Zr atomic fraction 10%-25%, V atomic fraction 10%- 25%, the atomic fraction of Cr is 10%-25%, the atomic fraction of Mo is 5%-25%, and the atomic fraction of W is 5%-25%.
4. The refractory high-entropy amorphous alloy material according to claim 1, wherein the atomic fractions of the non-refractory metal elements are respectively: the atomic fraction of Ni is 10%-25%, and the atomic fraction of Co is 10%- 25%, the atomic fraction of Al is 5%-25%, the atomic fraction of Si is 5%-25%, and the atomic fraction of B is 5%-10%.
5. A method for preparing the refractory high-entropy amorphous alloy material according to any one of claims 1-4, characterized in that it comprises:

   (1) batching is carried out according to the atomic fraction of each element of the refractory high-entropy amorphous alloy material, and the smelting is uniform to make a master alloy ingot;

   (2) The master alloy ingot is melted and then sprayed onto the surface of a rotating copper roll to obtain a refractory high-entropy amorphous alloy strip.
6. The preparation method of the refractory high-entropy amorphous alloy material according to claim 5, characterized in that, the elements and atomic fractions of the refractory high-entropy amorphous alloy material are: Hf atomic fraction is 19%-20 %, Ni atomic fraction is 19%-20%, Ta atomic fraction is 19%-20%, Co atomic fraction is 19%-20%, Nb atomic fraction is 19%-20%, V atomic fraction is 19%-20 %, Re atomic fraction is 5%-7%, B atomic fraction is 5%-7%, W atomic fraction is 5%-7%, Al atomic fraction is 5%-7%, Mo atomic fraction is 5%-7 %, Si atomic fraction is 5%-7%.
7. The preparation method of the refractory high-entropy amorphous alloy material according to claim 5, characterized in that, the melting step is: at a vacuum degree of 4.0×10 ^-3 -5.0×10 ^-3 Pa, the electric current Arc melting under 80-360A for 3-4min.
8. The method for preparing refractory high-entropy amorphous alloy material according to claim 5, characterized in that the density of the master alloy ingot is ≤13.0 g/cm ³ .
9. The preparation method of the refractory high-entropy amorphous alloy material according to claim 5, characterized in that the melted master alloy ingot is sprayed onto the surface of the copper roller when the vacuum degree is below 10Pa, and the linear velocity of the surface of the copper roller is Greater than 20m/s.
10. The application of the refractory high-entropy amorphous alloy material prepared by the method for preparing the refractory high-entropy amorphous alloy material according to claim 5 in nuclear reactors and nuclear power in high-temperature or marine environments, and in pipeline transportation in corrosive environments Applications.

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