Multi-element microalloyed high-temperature high-entropy amorphous alloy and preparation method thereof

Abstract

The invention discloses a multi-element microalloyed high-temperature and high-entropy amorphous alloy and a preparation method thereof. The chemical formula of the high-temperature and high-entropy amorphous alloy is WaMobCrcTadNbeRefOsgIrhCiBjREk, rE represents a rare earth element; mo, Cr, Nb, Ir and RE are microalloying elements; in terms of atomic percent (at.%), the contents of the elements meet the following conditions: a is 20-40, b is 1-5, c is 1-5, d is 5-15, e is 1-5, f is 10-25, g is 5-15, h is 1-5, i is 5-10, j is 10-25, k is 1-4, a + b + c is 25-45, d + e is 10-20, f + g + h is 16-40, i + j is 15-30, and a + b + c + d + e + f + g + h + i + j + k = 100; the preparation process is simple, and the prepared high-entropy amorphous alloy has the advantages of high crystallization temperature, high hardness, high strength, high corrosion resistance, excellent molding size and excellent performance adjustability; the application potential in manufacturing of high-tolerance precision mechanical components, forming dies or high-precision surface grinding machining materials is huge.

Description

Technical Field

[0001] The invention belongs to the field of high entropy amorphous alloys, and in particular relates to a multi-element microalloyed high-temperature high entropy amorphous alloy and a preparation method thereof. Background Art

[0002] High entropy amorphous alloys are a new type of alloy that has the characteristics of high entropy alloys with multiple principal components (mostly composed of no less than five elements in equiatomic ratios or nearly equiatomic ratios) and the characteristics of long-range disorder of traditional amorphous alloys in structure. Therefore, compared with high entropy alloys and traditional amorphous alloys with the same composition, high entropy amorphous alloys usually have more unique mechanical, physical and chemical properties and thermodynamic behavior and stability. Therefore, this type of alloy not only helps to broaden the exploration of potential applications of amorphous alloys and high entropy alloys, but also helps to analyze the general laws of the influence of "amorphization" of high entropy alloy structure and "high entropy" of traditional amorphous alloy composition on alloy composition structure and properties. Despite this, due to the requirements of the multi-principal component characteristics of "high entropy", the current system and number of high entropy amorphous alloys are still very limited. At the same time, since the components of existing high entropy amorphous alloys are mainly elements with low melting points (mostly not exceeding 2000℃), the initial crystallization temperature of most high entropy amorphous alloys currently does not exceed 700℃. It is well known that the mechanical properties of amorphous alloys, such as hardness and strength, are often positively correlated with their thermal properties, such as the initial crystallization temperature. Therefore, the room temperature fracture strength (σ f ) and Vickers microhardness (H v ) are not higher than 4GPa and 13GPa respectively. In addition, there is still a great lack of high-entropy amorphous alloys that combine high crystallization temperature (or high temperature resistance) with high performance (such as high hardness and strength and resistance to harsh environmental corrosion, etc.) and block size and shape (three-dimensional dimensions are not less than 1mm). These characteristics not only make it difficult for most existing high-entropy amorphous alloys to serve at higher temperatures without crystallization failure, but also make it difficult to explore the service behavior and characteristics of such alloys in a wider temperature range, more systems, and more diverse size dimensions and shape complexities, which seriously restricts the potential application of such alloys as high-tolerance micro-gears, micro-bearings, micro-tools and other precision mechanical components or their molding mold preparation materials under near-extreme conditions such as high temperature, wear resistance, and corrosion resistance. Summary of the invention

[0003] The present invention provides a multi-element microalloyed high-temperature high-entropy amorphous alloy and a preparation method thereof, which solves the problems in the prior art of insufficient variety and quantity of high-entropy amorphous alloys, insufficient thermal properties, hardness and strength.

[0004] In order to achieve the above object, the technical solution of the present invention is as follows:

[0005] In a first aspect, the present invention provides a multi-element microalloyed high-temperature high-entropy amorphous alloy, wherein the chemical formula of the high-temperature high-entropy amorphous alloy is W a Mo b Cr c Ta d Nb e Re f Os g Ir h C i B j RE k ; wherein RE represents a rare earth element; Mo, Cr, Nb, Ir and RE are microalloying elements; the content of each element is expressed in atomic percentage (at.%) and satisfies the following conditions: a is 20 to 40, b is 1 to 5, c is 1 to 5, d is 5 to 15, e is 1 to 5, f is 10 to 25, g is 5 to 15, h is 1 to 5, i is 5 to 10, j is 10 to 25, k is 1 to 4, and a+b+c is 25 to 45, d+e is 10 to 20, f+g+h is 16 to 40, i+j is 15 to 30, and a+b+c+d+e+f+g+h+i+j+k=100.

[0006] Furthermore, the high-temperature high-entropy amorphous alloy is a strip material or a block material, and the block material includes a rod shape with a maximum diameter of 1.3 mm.

[0007] Furthermore, the RE is a combination of one or more rare earth elements Y, Er, Gd, and Dy.

[0008] Furthermore, the chemical formula of the high temperature high entropy amorphous alloy is W 34 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 15 Y 2 .

[0009] Furthermore, the chemical formula of the high temperature high entropy amorphous alloy is W 30 Mo 2 Cr 2 Ta 9 Nb 2 Re 20 Os 7 Ir 2 C 6 B 18 Y 1 Er 1 .

[0010] Furthermore, the chemical formula of the high temperature high entropy amorphous alloy is W 26 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 22 Y 1 G 1 Dy 1 .

[0011] In a second aspect, the present invention provides a method for preparing the above-mentioned high-temperature high-entropy amorphous alloy, comprising:

[0012] Ingredients: According to W a Mo b Cr c Ta d Nb e Re f Os g Ir h C i B j RE k Weigh each raw material according to the chemical formula;

[0013] Melting the master alloy ingot: put the weighed raw materials into a vacuum arc melting furnace, and refine them 1 to 4 times to make the raw materials melt evenly, and take out the master alloy ingot after cooling in the furnace;

[0014] Preparation of high-entropy amorphous alloy: using an induction furnace in a rapid solidification device to completely melt the master alloy ingot to obtain an alloy melt, and rapidly cooling and solidifying the alloy melt by melt spinning or copper mold casting to obtain a high-temperature high-entropy amorphous alloy of a strip material or a block material.

[0015] Further, the alloy melt is rapidly cooled and solidified by the copper mold casting method to obtain a block material, wherein the block material includes a rod-like shape with a maximum diameter of 1.3 mm;

[0016] The alloy melt is rapidly cooled and solidified by the melt spinning method to obtain a strip material, and the thickness of the strip material is 20 to 30 μm.

[0017] Furthermore, the conditions for smelting the master alloy ingot are: adjusting the vacuum degree in the furnace to ≤4×10 -3 Pa, melting temperature 3500℃~4500℃, single-pass melting time 1~4min;

[0018] The conditions for preparing the strip material by melt spinning quenching method are: vacuum degree 1-3×10 -2Pa, induction current 25 ~ 30A, injection pressure 0.04 ~ 0.07MPa, copper wheel speed 2500 ~ 3500r / min;

[0019] The conditions for preparing the block material by the copper mold casting method are: vacuum degree 1-3×10 -2 Pa, induced current 25~30A, injection molding pressure 0.05~0.08MPa.

[0020] In the third aspect, the present invention provides the use of the above-mentioned multi-element microalloyed high-temperature high-entropy amorphous alloy in the manufacture of precision mechanical components, their molding dies or high-precision surface grinding processing materials, wherein the precision mechanical components or their molding dies are used in high-temperature, wear-resistant and corrosion-resistant environments.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The multi-element microalloyed high-temperature high-entropy amorphous alloy provided by the present invention has a remarkable feature that it contains at least five microalloying elements, which are richer than the number of microalloying elements in most existing high-entropy amorphous alloys; these microalloying elements not only play a microalloying role, but also enhance the high-entropy characteristics of the alloy, specifically: the microalloying elements Mo and Cr together with the same group element W constitute the first type of principal element, Nb and the same group element Ta form the second type of principal element, and Ir and the adjacent Re and Os in the periodic table form the third type of principal element, so that these microalloying elements have high-entropy effects at the same time. The synergistic effect of multi-element microalloying and high-entropy makes the alloy components present significant atomic radius differences and diversified mixing enthalpy (including positive, negative and zero values), thereby forming a more complex atomic stacking structure and strengthened mutual bonding; this structural characteristic significantly improves the amorphous forming ability of the alloy and the controllability of its performance. In contrast, existing technologies are usually limited to the microalloying effect of a single element and fail to effectively combine the advantages of microalloying and high entropy. Therefore, the formation ability and performance regulation effect of high entropy amorphous alloys are extremely limited.

[0023] 2. The multi-element microalloyed high-temperature high-entropy amorphous alloy provided by the present invention has an initial crystallization temperature (T x ) is higher than 950℃, which is at least 250℃ higher than most existing high-entropy amorphous alloys; this feature gives the alloy excellent thermal properties, allowing it to maintain amorphous stability at higher temperatures without crystallization failure. This advantage not only facilitates the study of the performance and behavior of this type of alloy under near-extreme conditions such as high temperature, but also provides the possibility for its application in the manufacture of high-tolerance micro-gears, micro-bearings, micro-tools and other precision mechanical components or their forming molds, allowing it to serve safely in harsh high-temperature environments, showing significant application value and economic benefits.

[0024] 3. The multi-element microalloyed high-temperature high-entropy amorphous alloy provided by the present invention has a Vickers microhardness (H v ) exceeds 17GPa, which is at least 4GPa higher than most existing high-entropy amorphous alloys; at the same time, its fracture strength (σ f ) is not less than 5GPa, which is at least 1GPa higher than that of most existing high-entropy amorphous alloys. This excellent toughness makes it a promising new material in the field of high-precision surface grinding. In addition, the alloy has no obvious weight loss after being immersed in 2mol / L HCl solution for 7 days, showing excellent corrosion resistance, which far exceeds the corrosion resistance of most existing high-entropy amorphous alloys in 1mol / L HCl solution.

[0025] 4. The multi-element microalloyed high-temperature high-entropy amorphous alloy provided by the present invention can be used to prepare rod-shaped block materials with a critical diameter of not less than 1 mm and a maximum diameter of 1.3 mm through composition optimization; this feature not only facilitates the acquisition of various mechanical performance parameters such as the strength of the alloy, but also expands the possibility of exploring its potential applications in multiple sizes and complex shapes; in contrast, most existing high-entropy amorphous alloys are difficult to simultaneously possess high crystallization temperature, high hardness, high strength, high corrosion resistance and a block morphology with three-dimensional dimensions of not less than 1 mm.

[0026] Of course, the implementation of the various technical solutions of the present invention does not necessarily require achieving all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, drawings of other embodiments can be obtained based on these drawings without paying creative work.

[0028] Figure 1 X-ray diffraction (XRD) diagrams of high entropy amorphous alloy cast samples corresponding to Examples 1 to 3 of the present invention;

[0029] Figure 2 The following are actual photos of the high entropy amorphous alloy cast samples corresponding to Example 1 and Implementation 2 of the present invention. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below by specific embodiments in conjunction with the accompanying drawings. Wherein similar elements in different embodiments adopt associated similar element numbers. In the following embodiments, many detailed descriptions are for making the present application better understood. However, those skilled in the art can easily recognize that some features can be omitted in different situations, or can be replaced by other elements, materials, methods. In some cases, some operations related to the present application are not shown or described in the specification, this is to avoid the core part of the present application being overwhelmed by too much description, and for those skilled in the art, it is not necessary to describe these related operations in detail, and they can fully understand the related operations according to the description in the specification and the general technical knowledge in the art.

[0031] In addition, the features, operations or characteristics described in the specification can be combined in any appropriate manner to form various implementations. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various sequences in the specification and the drawings are only for the purpose of clearly describing a certain embodiment and are not meant to be a required sequence, unless otherwise specified that a certain sequence must be followed.

[0032] The present invention designs a high-entropy amorphous alloy which has component characteristics different from those of existing high-entropy amorphous alloys, has excellent comprehensive performance, has high potential application value, and can be prepared into a block.

[0033] The chemical formula of the high entropy amorphous alloy is W a Mo b Cr c Ta d Nb e Re f Os g Ir h C i B j RE k ; wherein RE represents a rare earth element, which may be a combination of one or more of Y (yttrium), Er (erbium), Gd (gadolinium), and Dy (dysprosium); Mo, Cr, Nb, Ir, and RE are microalloying elements; wherein the content of each element is in atomic percentage (at.%), specifically as follows: a is 20 to 40, b is 1 to 5, c is 1 to 5, d is 5 to 15, e is 1 to 5, f is 10 to 25, g is 5 to 15, h is 1 to 5, i is 5 to 10, j is 10 to 25, k is 1 to 4, and a+b+c is 25 to 45, d+e is 10 to 20, f+g+h is 16 to 40, i+j is 15 to 30, and a+b+c+d+e+f+g+h+i+j+k=100.

[0034] The present invention is further described below by means of several typical embodiments:

[0035] Embodiment 1:

[0036] The present embodiment provides a multi-element microalloyed high-temperature high-entropy amorphous alloy, whose chemical formula is W 34 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 15 Y 2 , prepared by the following method:

[0037] Step 1, ingredients: according to the composition, calculate and weigh the required pure W, pure Mo, pure Cr, pure Ta, pure Nb, pure Re, pure Os, pure Ir, pure C, pure B and pure Y with a purity greater than 99wt.%;

[0038] Step 2: Melting the master alloy ingot: Place the raw materials weighed in step 1 into a vacuum arc melting furnace and adjust the vacuum degree in the furnace to 3×10 －3 Pa, the smelting temperature is 4000℃, the smelting time is 2min, and the raw materials are smelted evenly for 3 times. After cooling in the furnace, the master alloy ingot is taken out;

[0039] Step 3: Preparation of high entropy amorphous alloy: W prepared in step 2 34 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 1 5 Y 2 The alloy ingot was placed in a rapid solidification device and completely melted in its electromagnetic induction furnace. Then, a rod-shaped block material sample with a diameter of 1.3 mm was obtained by copper mold casting. The preparation parameters of the copper mold casting method were vacuum degree 2×10 -2 Pa, induced current 27A, injection pressure 0.07MPa.

[0040] See the actual photo of the rod-shaped block material obtained in Example 1. Figure 2 (a) The material is cylindrical with a smooth surface and metallic luster. The measured diameter is 1.3 mm ± 0.05 mm. The overall appearance is uniform and consistent, reflecting the excellent forming properties of high-entropy amorphous alloys.

[0041] like Figure 1 As shown, the W prepared in Example 1 34 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 15 Y 2 The rod-shaped bulk material samples were tested and analyzed by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and mechanical experiments. The results showed that its structure was a single amorphous state (see Figure 1 ), the initial crystallization temperature is 1018℃, the room temperature Vickers hardness is 21.6GPa, and the room temperature fracture strength is 5.5GPa.

[0042] Embodiment 2:

[0043] The present embodiment provides a multi-element microalloyed high-temperature high-entropy amorphous alloy, whose chemical formula is W 30 Mo 2 Cr 2 Ta 9 Nb 2 Re 20 Os 7 Ir 2 C 6 B 18 Y 1 Er 1 , prepared by the following method:

[0044] Step 1, ingredients: according to the composition, calculate and weigh the required pure W, pure Mo, pure Cr, pure Ta, pure Nb, pure Re, pure Os, pure Ir, pure C, pure B, pure Y and pure Er with a purity greater than 99wt.%;

[0045] Step 2: Melting the master alloy ingot: Place the raw materials weighed in step 1 into a vacuum arc melting furnace and adjust the vacuum degree in the furnace to 3×10 －3 Pa, smelting temperature is 4100℃, smelting time is 1.5min, refining is performed 4 times to make the raw materials smelted evenly, and the master alloy ingot is taken out after cooling in the furnace;

[0046] Step 3: Preparation of high entropy amorphous alloy: W prepared in step 2 30 Mo 2 Cr 2 Ta 9 Nb 2 Re 20 Os 7 Ir 2 C 6 B18 Y 1 Er 1 The alloy ingot was placed in a rapid solidification device and completely melted in an electromagnetic induction furnace. Then, a 22 μm thick alloy strip sample was obtained by melt spinning method. The preparation parameters of melt spinning method were: vacuum degree 2×10 -2 Pa, induced current 28A, spraying pressure 0.05MPa, copper wheel speed 3000r / min.

[0047] See the actual photo of the strip material obtained in Example 2. Figure 2 (b) The material is in the form of a thin strip with a smooth surface and metallic luster. The thickness is 22 μm and the overall appearance is uniform, reflecting the excellent forming properties of high-entropy amorphous alloys.

[0048] like Figure 1 As shown, the W prepared in Example 2 30 Mo 2 Cr 2 Ta 9 Nb 2 Re 20 Os 7 Ir 2 C 6 B 18 Y 1 Er 1 The strip material samples were analyzed by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and mechanical properties test. The results showed that the sample structure was a single amorphous state (see Figure 1 ), the initial crystallization temperature reaches 1020℃, and the room temperature Vickers microhardness is 21.5GPa.

[0049] Embodiment 3:

[0050] The chemical formula of a multi-element microalloyed high-temperature high-entropy amorphous alloy provided in this embodiment is W 26 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 22 Y 1 G 1 Dy 1 , can be prepared by the following method:

[0051] Step 1, ingredients: according to the composition, calculate and weigh the required purity greater than 99wt.% of pure W, pure Mo, pure Cr, pure Ta, pure Nb, pure Re, pure Os, pure Ir, pure C, pure B, pure Y, pure Gd and pure Dy;

[0052] Step 2: Melting the master alloy ingot: Place the raw materials weighed in step 1 into a vacuum arc melting furnace and adjust the vacuum degree in the furnace to 3×10 －3 Pa, smelting temperature is 3800℃, smelting time is 2min, refining is done 3 times to make the raw materials smelted evenly, and the master alloy ingot is taken out after cooling in the furnace;

[0053] Step 3: Preparation of high entropy amorphous alloy: W prepared in step 2 26 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 2 2 Y 1 G 1 Dy 1 The alloy ingot was placed in a rapid solidification device and completely melted in an electromagnetic induction furnace. Then, a 22 μm thick alloy strip sample was obtained by melt spinning method. The preparation parameters of melt spinning method were: vacuum degree 2×10 -2 Pa, induced current 26A, spraying pressure 0.05MPa, copper wheel speed 3000r / min.

[0054] The actual photo of the strip material prepared in Example 3 is similar to that in Example 2. The material is in the form of a thin strip with a smooth surface and metallic luster, a thickness of 22 μm, and a uniform overall appearance, reflecting the excellent forming properties of the high-entropy amorphous alloy.

[0055] like Figure 1 As shown, the W obtained in Example 3 26 Mo 2 Cr 2 Ta 10 Nb 2 Re 15 Os 10 Ir 2 C 6 B 22 Y 1 G 1 Dy 1 The strip material samples were analyzed by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and mechanical properties test. The results showed that the sample structure was a single amorphous state (see Figure 1), the initial crystallization temperature reaches 1008℃, and the room temperature Vickers microhardness is 20.6GPa.

[0056] Comparative Example 1:

[0057] Select patent application number: 201710854943.4, patent name: A high entropy bulk amorphous alloy and its preparation method, and the Zr with the highest initial crystallization temperature involved in it 28 Ti 24 Be 23 Cu 9 Ni 10 Al 6 High entropy amorphous alloy; Patent application number: 201510293400.0, Patent name: A soft magnetic FeCoNiMB high entropy bulk amorphous alloy and its preparation method, the Fe with the highest initial crystallization temperature involved 25 Co 25 Ni 25 P 5 Si 7.5 B 12.5 and the highest strength Fe 25 Co 25 Ni 25 Si 7.5 B 17.5 High entropy amorphous alloy; Patent application number: 202311741065.7, Patent name: A bulk rare earth-based high entropy amorphous alloy with high magnetocaloric effect and its preparation method, the Gd with the highest initial crystallization temperature involved 11 Tb 11 Dy 11 Ho 11 Er 11 Co 17 Al 28 High entropy amorphous alloy; Patent application number: 201310224674.5, Patent name: High entropy amorphous alloy material and preparation method thereof, Nb with the highest initial crystallization temperature involved 20 Ni 20 Zr 20 Co 20 Cu 20 and the highest strength Ti 20 Hf 20 Ni 20 Cu 20 Be 20 High entropy amorphous alloy; compared with the high entropy amorphous alloy involved in this application. The relevant performance parameter values ​​of each alloy in the comparative example are shown in Table 1:

[0058] Table 1 Performance parameter values ​​of various high entropy amorphous alloys in the proportion

[0059] Composition (at.%) Initial crystallization temperature (℃) Breaking or yield strength (GPa) <![CDATA[Zr 28 IT 24 Drink 23 With 9 us 10 the 6 ]]> 444 2.024 <![CDATA[Fe 25 Co 25 Ni 25 Q 5 Si 7.5 B 12.5 ]]> 543 3.250 <![CDATA[Fe 25 Co 25 Ni 25 Si 7.5 B 17.5 ]]> 534 3.624 <![CDATA[Gd 11 Tb 11 Dy 11 Ho 11 ◾ 11 Co 17 Al 28 , 432 - <![CDATA[Nb 20 Ni 20 Zr 20 Co 20 Cu 20 ]]> 548 - <![CDATA[Ti 20 Hf 20 Ni 20 Cu 20 Be 20 ]]> 487 2.425

[0060] It can be seen that the high entropy amorphous alloy comparison examples of these different systems have a maximum initial crystallization temperature of 548°C (or 821K) and a maximum room temperature fracture strength of 3.624GPa (or 3624MPa). These performance parameter values ​​are 470°C and 1.876GPa lower than the corresponding performance parameter values ​​of Example 1 in this application. This result fully illustrates that "a multi-element microalloyed high-temperature high-entropy amorphous alloy provided in the present invention has an initial crystallization temperature (T x ), which is at least 250°C higher than the corresponding values ​​of most existing high-entropy amorphous alloys; at the same time, it also has a fracture strength (σ f ), which is at least 1 GPa higher than the corresponding value of most existing high-entropy amorphous alloys. The high-entropy amorphous alloy of the present invention can be used as a potential room-temperature high-strength and harsh environment corrosion-resistant material, as well as a potential high-temperature resistant material under near-extreme conditions such as 950°C or higher, and has high application value and economic benefits.

[0061] Comparative Example 2:

[0062] In order to further illustrate the synergistic gain effect of the multi-element microalloying strategy on the multi-dimensional performance indicators of high entropy amorphous alloys and its technical evolution law in the present invention, based on the W-Ta-Re-Os system amorphous alloy disclosed in the applicant's prior patent CN111363987A, a comparative analysis of its component design strategy and performance regulation mechanism is conducted, as follows:

[0063] W obtained from Example 3 of CN111363987A 19 Ta 17 Re 19 Os 19 Ir 2 Ru 2 Mo 2 C 10 B 10 The patent records that after the alloy is prepared by melt spinning, its X-ray diffraction spectrum shows a typical amorphous diffuse scattering peak (such as Figure 1 Although the initial crystallization temperature (Tx) of this type of alloy is measured to be over 950℃, the room temperature Vickers microhardness (H v ) exceeds 17 GPa, but the final obtained tape is about 30 μm thick.

[0064] This result reveals the significant technical limitations of the system: First, its compositional characteristics show that the microalloying elements in the system are only Ir, Ru, and Mo, and the microalloying elements are not rich enough. Second, the atomic radius characteristics of the components in the system are that the atomic radius of the Ta element is the largest at 0.143nm; the atomic radius of the microalloying elements Ir (0.135nm) and Ru (0.133nm) is similar to the atomic radius of the components with higher content in the system Re (0.137nm) and Os (0.135nm), and the atomic radius of the microalloying element Mo (0.136nm) is similar to that of another component with higher content in the system W (0.137nm). The atomic radii of these six elements (W, Mo, Re, Os, Ir and Ru) are similar, and the atomic radii of these six elements (W, Mo, Re, Os, Ir and Ru) are relatively large (all concentrated between 0.133 and 0.137nm); the atomic radii of B (0.09nm) and C (0.077nm) are the smallest (both less than 0.1nm); and there are no components with larger atomic radii or smaller atomic radii (such as larger than the atomic radii of B and C but smaller than the atomic radii of the six elements W, Mo, Re, Os, Ir and Ru). Third, the mixing enthalpy between different components in this system is negative or zero, and there is no positive value. These characteristics make it difficult to form more diverse atomic radius difference characteristics and mixing enthalpy (such as positive, negative and zero) between different components in the amorphous alloy system of patent CN111363987A, and thus it is impossible to obtain a more complex atomic stacking structure and bonding between atoms to form an amorphous alloy melt with higher thermal stability. Ultimately, it is difficult to achieve a higher amorphous forming ability and it is impossible to obtain millimeter-level bulk amorphous alloys by copper mold casting and other methods, and micron-level strips can only be obtained by melt spinning.

[0065] Therefore, the application of this technology system is limited to the field of thin sheets or coatings, and it cannot meet the needs of near-net forming and processing of high-temperature precision mechanical components such as high-tolerance micro-gears, micro-bearings, and micro-tools or their forming molds for multi-dimensional dimensions (such as both micron and millimeter levels). In addition, since only micron-level strips can be prepared without millimeter-level blocks, it is difficult to effectively evaluate the mechanical behavior of the alloy through conventional axial quasi-static compression tests, and it is impossible to fully analyze its corrosion behavior and corrosion resistance with multi-size and multi-shape specimens. These limitations significantly restrict the breadth and depth of its industrial application.

[0066] In view of the above technical bottlenecks, the present invention effectively regulates the amorphous forming ability by introducing at least five microalloying elements and their multi-component synergistic high entropy and microalloying effects, and successfully prepares a high entropy amorphous alloy material that integrates high crystallization temperature, high hardness, high strength, high corrosion resistance and block size (maximum diameter of 1.3mm). Compared with the limitation that only about 30μm thin strips can be obtained in CN111363987A, the blocky high entropy amorphous alloy of the present invention provides an alternative material for high-tolerance micro-gears, micro-bearings and micro-tools with a maximum diameter of 1.3mm directly formed by copper mold casting. Precision mechanical components; at the same time, it is also suitable for high-demand processes such as laser cladding additive manufacturing to prepare high-temperature resistant and wear-resistant amorphous alloy components of multiple sizes and complex shapes. In addition, with its excellent surface finish, the alloy can also be used as a candidate material for hot forming molds for precision micromechanical components.

[0067] Compared with the CN111363987A patent, the innovative design of the present invention is reflected in the following key aspects:

[0068] 1. Multi-element microalloying and high entropy collaborative design: Introduce rare earth elements RE with larger atomic radius (Y0.182nm, Er 0.174nm, Gd 0.178nm, Dy 0.175nm) and smaller Cr (0.125nm, larger than B and C but smaller than W, Mo, Re, Os, Ir), and replace Ru in CN111363987A with Nb (0.143nm), so that the microalloying elements increase to more than five types of Mo, Cr, Nb, Ir, and RE. At the same time, Mo and Cr form the first type of principal element with W, Nb and Ta form the second type of principal element, and Ir, Re, and Os form the third type of principal element, strengthening the high entropy effect. This design forms a significant difference in atomic radius and a variety of mixing enthalpy (positive, negative, and zero values), constructs a complex atomic stacking structure and a stable amorphous melt, significantly improves the amorphous forming ability, and realizes the preparation of bulk materials with a maximum diameter of 1.3mm.

[0069] 2. Millimeter-scale block forming and mechanical property optimization: Rod-shaped block materials with a maximum diameter of 1.3 mm were prepared through conventional copper mold casting, which expanded the application potential of multiple sizes and complex shapes. The fracture strength was measured to be 5.5 GPa through a simple axial quasi-static compression test.

[0070] 3. Improvement of corrosion resistance: The corrosion resistance of the alloy in 2 mol / L HCl solution was comprehensively evaluated using strip and 1.3 mm block bar samples. There was no obvious weight loss after immersion for 7 days, demonstrating excellent corrosion resistance.

[0071] 4. Improved overall performance: Achieve the unification of high crystallization temperature, high hardness, high strength, high corrosion resistance and a maximum block size of 1.3mm, breaking through the limitations of existing technologies.

[0072] The above specific examples are used to illustrate the present invention, which is only used to help understand the present invention and is not intended to limit the present invention. For those skilled in the art, according to the concept of the present invention, some simple deductions, modifications or substitutions can be made.

Claims

1. A multi-element microalloyed high temperature high entropy amorphous alloy, characterized in that: The chemical formula of the high temperature high entropy amorphous alloy is W a Mo b Cr c Ta d Nb e Re f Os g Ir h C i B j RE k ; Where RE represents rare earth element; Mo, Cr, Nb, Ir and RE are microalloying elements; the content of each element, measured in atomic percentage (at.%), satisfies the following conditions: a is 20-40, b is 1-5, c is 1-5, d is 5-15, e is 1-5, f is 10-25, g is 5-15, h is 1-5, i is 5-10, j is 10-25, k is 1-4, and a+b+c is 25-45, d+e is 10-20, f+g+h is 16-40, i+j is 15-30, and a+b+c+d+e+f+g+h+i+j+k=100.

2. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 1, characterized in that: The high temperature high entropy amorphous alloy is a strip material or a block material. The block material includes a rod shape with a maximum diameter of 1.3 mm.

3. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 1, characterized in that: The RE is a combination of one or more rare earth elements Y, Er, Gd, and Dy.

4. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 1, characterized in that: The chemical formula of the high temperature high entropy amorphous alloy is W 34 Mo2Cr2Ta 10 Nb2Re 15 Os 10 Ir2C6 15 Y2.

5. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 1, characterized in that: The chemical formula of the high temperature high entropy amorphous alloy is W 30 Mo2Cr2Ta9Nb2Re 20 Os7Ir2C6B 18 Y1Er1.

6. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 1, characterized in that: The chemical formula of the high temperature high entropy amorphous alloy is W 26 Mo2Cr2Ta 10 Nb2Re 15 Os 10 Ir2C6 22 Y1Gd1Dy1.

7. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 1, characterized in that: The preparation method of the high temperature high entropy amorphous alloy comprises: Ingredients: According to W a Mo b Cr c Ta d Nb e Re f Os g Ir h C i B j RE k Weigh each raw material according to the chemical formula; Melting the master alloy ingot: put the weighed raw materials into a vacuum arc melting furnace, and refine them 1 to 4 times to make the raw materials melt evenly, and take out the master alloy ingot after cooling in the furnace; Preparation of high-entropy amorphous alloy: using an induction furnace in a rapid solidification device to completely melt the master alloy ingot to obtain an alloy melt, and rapidly cooling and solidifying the alloy melt by melt spinning or copper mold casting to obtain a high-temperature high-entropy amorphous alloy of a strip material or a block material.

8. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 7, characterized in that: Rapidly cooling and solidifying the alloy melt by the copper mold casting method to obtain a block material, wherein the block material includes a rod-like shape with a maximum diameter of 1.3 mm; The alloy melt is rapidly cooled and solidified by the melt spinning method to obtain a strip material, and the thickness of the strip material is 20 to 30 μm.

9. The multi-element microalloyed high temperature high entropy amorphous alloy according to claim 7, characterized in that: The conditions for melting the master alloy ingot are: adjusting the vacuum degree in the furnace to ≤4×10 -3 Pa, melting temperature 3500℃~4500℃, single-pass melting time 1~4min; The conditions for preparing the strip material by melt spinning quenching method are: vacuum degree 1-3×10 -2 Pa, induction current 25 ~ 30A, injection pressure 0.04 ~ 0.07MPa, copper wheel speed 2500 ~ 3500r / min; The conditions for preparing the block material by the copper mold casting method are: vacuum degree 1-3×10 -2 Pa, induced current 25~30A, injection molding pressure 0.05~0.08MPa.

10. Use of the multi-element microalloyed high-temperature high-entropy amorphous alloy according to any one of claims 1 to 9 in the manufacture of precision mechanical components, their forming molds or high-precision surface grinding materials, wherein the precision mechanical components or their forming molds are used in high-temperature, wear-resistant and corrosion-resistant environments.

Images