Large-sized rejuvenated amorphous alloy and preparation method thereof

Abstract

The application provides a large-size rejuvenated amorphous alloy and a preparation method thereof. By using a sample with size gradient change, through saturation treatment, the middle region of the gradient sample is rejuvenated in a large-size range (close to the critical size of amorphous formation) and severely (the relaxation enthalpy can reach 3.231 kJ / mol). Compared with the as-cast amorphous alloy, the room temperature compression plasticity of the rejuvenated sample obtained by the application is greatly improved, which provides a new idea for solving the brittleness problem of the amorphous alloy, and makes the amorphous alloy have an actual engineering application prospect.

Description

Technical Field

[0001] The present invention belongs to the technical field of improving the structure and performance of amorphous alloys, and particularly relates to a large-size rejuvenated amorphous alloy and a preparation method thereof. Background Art

[0002] Amorphous alloys are solid materials with short-range order and long-range disorder that form during the rapid cooling of an alloy melt. Since their discovery, their unique structure and exceptional properties have become a hot topic in the fields of condensed matter physics and materials science. Compared to traditional crystalline materials, amorphous alloys possess high strength, high elastic strain (approximately 2%), low thermal expansion coefficient, excellent soft magnetic properties, thermoplastic formability, and excellent corrosion resistance in acids, alkalis, and salts. These properties hold great promise for applications in machinery, electronics, shipbuilding, aerospace, and the military.

[0003] Crystalline materials contain structural defects such as dislocations, twins, and grain boundaries. Their initiation and sliding are the core mechanisms of plastic deformation in traditional metals, but this also causes crystalline materials to yield at relatively low stresses. Amorphous alloys, lacking defects such as grain boundaries and dislocations, exhibit high strength, high elastic limit, high fracture toughness, and excellent wear resistance far exceeding those of traditional crystalline alloys. However, during plastic deformation at room temperature, amorphous alloys are prone to forming localized nanoscale shear bands. The unstable and rapid expansion of these shear bands often leads to macroscopic brittle failure of the material, accompanied by very limited plasticity or ductility. More seriously, metastable amorphous alloys have a tendency to spontaneously undergo physical aging, a relaxation transition from a high-energy disordered state to a low-energy ordered state. This kinetic process further weakens the plastic deformation ability of amorphous alloys during service, and may even cause them to undergo a ductile-brittle transition and lose their plasticity. The brittleness induced by shear bands and physical aging seriously restricts the other excellent properties of amorphous alloys, greatly limiting their application.

[0004] In recent years, researchers at home and abroad have been applying external energy to amorphous alloy systems through methods such as high- and low-temperature thermal cycling, recovery annealing, irradiation treatment, elastic preloading, thermodynamic creep, and uniform and inhomogeneous deformation, such as cold rolling, high-pressure torsion, and high-pressure annealing, to "rejuvenate" their structures and achieve a more disordered, high-energy state. Research has shown that this anti-physical aging process can effectively delay or even inhibit the formation of shear bands, significantly improving the plastic deformation capacity of the rejuvenated amorphous alloys and laying a solid foundation for their practical applications. In summary, existing rejuvenation methods for amorphous alloys can be categorized into two types: mechanically activated rejuvenation and thermally activated rejuvenation. Mechanically activated rejuvenation can achieve large-scale rejuvenation within a sample, but the degree of rejuvenation is very low (characterized by the relaxation enthalpy, ΔH), typically <1.6 kJ / mol. Thermally activated rejuvenation achieves a higher degree of rejuvenation, but the resulting rejuvenated size is very small (approximately 50 microns). Overall, both rejuvenation methods offer limited improvements in the plasticity of amorphous alloys (less than 8%). In summary, existing methods for amorphous alloy rejuvenation, both domestically and internationally, are constrained by the volume-to-rejuvenation constraint. This means that drastic rejuvenation is limited to small volumes (tens of microns), while large-scale rejuvenation yields very low levels of rejuvenation. Therefore, a method that can achieve both large-scale amorphous alloy rejuvenation and drastic rejuvenation is urgently needed. Summary of the Invention

[0005] Therefore, the purpose of the present invention is to overcome the defects of the prior art and provide a large-scale rejuvenated amorphous alloy and its preparation method, thereby improving the energy state of the amorphous alloy and thus solving the room temperature brittleness problem of the amorphous alloy.

[0006] Before describing the present invention, the terms used in this article are defined as follows:

[0007] The term "rejuvenation" refers to the process by which an amorphous alloy transforms from a low-energy state to a high-energy state.

[0008] The term "size gradient" refers to the gradient change in the cross-sectional dimensions of the sample with height.

[0009] The term "σ y ” refers to: the yield strength of amorphous alloys.

[0010] The term "σ UCS ” refers to: the maximum compressive strength of amorphous alloys.

[0011] To achieve the above objectives, a first aspect of the present invention provides a rejuvenated amorphous alloy, wherein the cross-sectional diameter or side length of the rejuvenated amorphous alloy is 1 to 15 mm, preferably 2 to 12 mm, and more preferably 4 to 10 mm, and the plastic strain of the rejuvenated amorphous alloy is ≥5%, more preferably ≥10%, further preferably ≥15%, and even more preferably ≥17%.

[0012] According to the amorphous alloy of the first aspect of the present invention, the amorphous alloy is selected from the following alloy systems composed of elements: Zr-Cu-Al system, Zr-Cu-Ni-Al system, Cu-Zr-Ti-Hf system, Pd-Ni-P system, Pd-Cu-Ni-P system, Fe-Cr-Co-Mo-Mn-CBY amorphous steel system, La-Al-Ni system,

[0013] It is preferably selected from the following alloy systems: Zr-Cu-Al system, Zr-Cu-Ni-Al system, Cu-Zr-Ti-Hf system, Pd-Cu-Ni-P system, Fe-Cr-Co-Mo-Mn-CBY amorphous steel system,

[0014] More preferably, the alloy system is selected from the following element compositions: Zr-Cu-Al system, Zr-Cu-Ni-Al system, Cu-Zr-Ti-Hf system, and Fe-Cr-Co-Mo-Mn-CBY amorphous steel system.

[0015] According to the amorphous alloy of the first aspect of the present invention, the shape of the amorphous alloy is selected from one or more of the following: cylindrical rods, square pillars, and blocks of any shape, preferably cylindrical rods or square pillars, and more preferably cylindrical rods.

[0016] A second aspect of the present invention provides a method for preparing the rejuvenated amorphous alloy according to the first aspect, the method comprising the following steps:

[0017] (1) preparing cast amorphous alloy;

[0018] (2) processing the as-cast amorphous alloy prepared in step (1) into a sample with a size gradient;

[0019] (3) subjecting the size gradient sample prepared in step (2) to full loading treatment to obtain a rejuvenated amorphous alloy;

[0020] The cross-sectional diameter or side length of the rejuvenated amorphous alloy is 1 to 15 mm, preferably 2 to 12 mm, and more preferably 4 to 10 mm.

[0021] According to the method of the second aspect of the present invention, the degree of rejuvenation of the rejuvenated amorphous alloy is characterized by the magnitude of the relaxation enthalpy; wherein,

[0022] The relaxation enthalpy is calculated by formula (1):

[0023]

[0024] Where ΔH is the relaxation enthalpy, c p is the specific heat capacity of the alloy, RT is room temperature, and T1 is the temperature point near the glass transition point where the specific heat capacity of the alloy is the same as that at room temperature;

[0025] Preferably, the relaxation enthalpy is 0.2 to 4 kJ / mol, more preferably 2 to 4 kJ / mol, and even more preferably 3 to 4 kJ / mol.

[0026] According to the method of the second aspect of the present invention, the step (1) further comprises the following steps:

[0027] (A) preparing materials according to atomic percentages of pure metals, smelting, and cooling to obtain a master alloy ingot;

[0028] (B) remelting the master alloy ingot prepared in step (A) to obtain the cast amorphous alloy.

[0029] According to the method of the second aspect of the present invention, the step (B) further comprises: after remelting, sucking the melt into a water-cooled copper mold under a pressure difference to obtain the cast amorphous alloy;

[0030] Preferably, in step (A), the purity of the pure metal is 99.9% to 99.999%; and / or

[0031] Preferably, in step (B), the pressure difference is 10 3 ~10 5 Pa, preferably 10 4 ~5*10 4 Pa, more preferably 2*10 4 ~3*10 4 Pa.

[0032] According to the method of the second aspect of the present invention, wherein, in said step (2):

[0033] The processing method is selected from the following: lathe processing, wire cutting, spray casting, preferably lathe processing or wire cutting, more preferably lathe processing; and / or

[0034] The size of the sample with the size gradient at both ends is smaller than the middle size;

[0035] Preferably, the ratio of the end dimensions to the middle dimension of the sample with the size gradient is 0.7 to 1.0, preferably 0.8 to 0.95, and more preferably 0.8 to 0.9.

[0036] According to the method of the second aspect of the present invention, in the step (3), the full-load treatment method is quasi-static uniaxial compression or quasi-static uniaxial tension, preferably quasi-static uniaxial compression.

[0037] According to the method of the second aspect of the present invention, wherein, in said step (3):

[0038] The strain rate of the quasi-static uniaxial compression is 10 -6 s -1 ~10 -2 s -1 , preferably 10 -6 s -1 ~10 -3 s -1 , more preferably 10 -4 s -1 ~10 -3 s -1 ;

[0039] The full load time of the quasi-static uniaxial compression is 1 to 60 minutes, preferably 1 to 30 minutes, more preferably 3 to 10 minutes; and / or

[0040] The full load stress of the quasi-static uniaxial compression depends on the yield strength and maximum compressive strength of the as-cast amorphous alloy;

[0041] Preferably, the full load stress is 0.9σ y ~σ UCS , preferably σ y ~σ UCS , more preferably 1.1σ y ~σ UCS and / or

[0042] Preferably, 500MPa<σ y <5000MPa, 550MPa<σ UCS <5500MPa; more preferably, 1000MPa<σ y <3500MPa, 1050MPa<σ UCS <3800MPa; further preferably, 1500MPa<σ y <3000MPa, 1700MPa<σ UCS <3200MPa.

[0043] In response to the shortcomings of the above-mentioned amorphous alloy rejuvenation technology, the present invention provides a method for large-scale, drastic rejuvenation of amorphous alloys. According to a specific embodiment, the method includes the following steps:

[0044] (1) smelting to prepare an amorphous alloy of target composition;

[0045] (2) processing the amorphous alloy of step (1) into a gradient sample with varying dimensions;

[0046] (3) performing a saturation treatment on the gradient sample of step (2);

[0047] As the preferred technical solution:

[0048] In step (1), pure metal elements with a purity exceeding 99.9% are used to prepare the material according to the nominal composition (atomic percentage), and then smelted in a vacuum arc furnace and the melt is sucked into a water-cooled copper mold to obtain a cast amorphous alloy;

[0049] The processing method used in step (2) is lathe processing, wire cutting or spray casting; the sample is a gradient cylinder or gradient square cylinder; the size (a) at both ends of the gradient sample is smaller than the middle size (b), and the size gradient ratio a / b = 0.7 to 1.0;

[0050] In step (3), quasi-static uniaxial compression or quasi-static uniaxial tension is used for full load treatment, and the strain rate is 10 -6 s -1 ~10 -2 s -1 ;

[0051] The full load stress of the quasi-static uniaxial compression or quasi-static uniaxial tension depends on the yield strength and maximum compressive strength of the alloy (the specific values ​​of the yield strength and maximum compressive strength will vary with the type of alloy.

[0052] Full load stress range: 0.9σ y ~σ UCS , Figure 1 The dotted line segment in the figure indicates full load time of 1 to 60 minutes.

[0053] According to another specific embodiment, the method comprises the following steps:

[0054] (1) Processing the as-cast amorphous alloy into size-gradient samples;

[0055] (2) Saturation treatment of gradient samples;

[0056] The cast amorphous alloy in step (1) refers to a cast alloy material obtained by melting and casting;

[0057] The processing method used in step (1) is lathe processing, wire cutting or spray casting; the sample is a gradient cylinder or gradient square cylinder; the size (a) at both ends of the gradient sample is smaller than the middle size (b), and the size gradient ratio is: a / b = 0.7 to 1.0;

[0058] Step (2) uses quasi-static uniaxial compression or quasi-static uniaxial tension, and the strain rate is 10 -6 s -1 10 -2 s -1 ; the full load stress range is 0.9σ y ~σ UCS , σ y and σ UCS are the yield strength and the maximum compression strength of the alloy respectively, wherein 500MPa<σ y <5000MPa, 550MPa<σ UCS <5500MPa, and the full load time is 1-60min.

[0059] The large-size, severe recovery method of the amorphous alloy is used to improve the room temperature plasticity of the amorphous alloy.

[0060] In the prior art, how to store the external input energy (mechanical work or heat conduction) in the amorphous alloy during the recovery process of the amorphous alloy is the most critical problem of the recovery degree and the corresponding recovery volume, and scholars unanimously believe that the stress state of hydrostatic pressure can significantly improve the recovery degree. It is found on the basis of combining finite element simulation that the stress field in different size regions inside the size gradient sample is obviously different under the action of external load, and the stress field of hydrostatic pressure can appear in local regions. Therefore, the size gradient sample is introduced in the present application. It should be noted that the prior art uses a sample with equal cross-sectional size for recovery treatment, so the present application breaks the shackles of the prior art. On this basis, the gradient sample is loaded and treated, and the result is that the recovery degree of the sample is very low. Although the gradient sample can introduce hydrostatic pressure, there is not enough time for the atoms inside the alloy to move in a large range during the simple loading and unloading stage. After analysis and integration, it is found that the full load treatment can give the atoms inside the alloy sufficient movement time in the dynamic process, thereby giving the recovery a larger space for rising. Therefore, the full load treatment is selected on the basis of the gradient sample, and unexpected technical effects are achieved, the sample undergoes severe recovery, and the recovery degree is significantly greater than all prior art, and the recovery volume is also very considerable. It should be noted that the full load treatment is generally used to detect the creep and fatigue performance of the alloy, and the present technology uses the full load treatment as a preparation technology, which is essentially different from the prior art. Therefore, the present technology is gradually formed on the basis of theory and experiment, step by step exploration, in-depth and improvement. It is impossible to form the present technology by simply improving or nesting the prior art.

[0061] This invention utilizes samples with a size gradient and, through saturation treatment, results in a large size range in the central region of the gradient sample (approaching the critical size for glass-forming ability) and a dramatic rejuvenation (relaxation enthalpy up to 3.231 kJ / mol). Compared to as-cast amorphous alloys, the room-temperature compressive plasticity of the rejuvenated samples obtained in this invention is significantly improved, providing a new approach to addressing the brittleness of amorphous alloys and making them practical for engineering applications.

[0062] The large-scale rejuvenated amorphous alloy and its preparation method of the present invention may have but are not limited to the following

[0063] Beneficial effects:

[0064] 1. By improving the energy state of amorphous alloys, the room temperature brittleness of amorphous alloys can be solved. This method is easy to operate, low-cost, and effective. It can significantly improve the room temperature plasticity of amorphous alloys and provide high-quality experimental materials for the study of the mechanical properties, structural characteristics, and physical and chemical properties of amorphous alloys.

[0065] 2. Compared with the prior art, the rejuvenation method of the amorphous alloy of the present invention can achieve both large size and drastic rejuvenation. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which:

[0067] Figure 1 A schematic diagram of the full load stress range is shown.

[0068] Figure 2 The dimensions of the gradient cylinder in Example 1 are shown, where a=4 mm and b=4.5 mm.

[0069] Figure 3 A schematic diagram of full load processing in Example 1 is shown.

[0070] Figure 4 The diagram shows the sampling diagram and dimensions of the rejuvenation samples used for the compression test in Example 1.

[0071] Figure 5 The X-ray diffraction spectra of the as-cast sample 1 and the rejuvenated sample 1 in Example 1 are shown.

[0072] Figure 6 The differential scanning calorimeter heat flow curves of the as-cast sample 1 and the rejuvenated sample 1 in Example 1 are shown.

[0073] Figure 7 The compressive engineering stress-strain curves of the as-cast sample 2 and the rejuvenated sample 2 in Example 1 are shown.

[0074] Figure 8Gradient square rod size plot of Example 2 is shown, where a = 2.5 mm, b = 3 mm.

[0075] Figure 9 Differential scanning calorimeter heat flow curves of as-cast sample 3 and rejuvenated sample 3 of Example 2 are shown.

[0076] Figure 10 Compression engineering stress-strain curves of as-cast sample 3 and rejuvenated sample 3 of Example 2 are shown.

[0077] Figure 11 Flow chart of the rejuvenation method of the amorphous alloy of the present application is shown. DETAILED DESCRIPTION

[0078] The present application will be further described in the following specific examples. It should be understood, however, that these examples are intended to be illustrative only and should not be construed as limiting the present application in any way.

[0079] This section provides a general description of the materials and methods used in the experiments of the present application. Although many of the materials and methods used to achieve the objectives of the present application are well known in the art, the present application is described in as much detail as possible. It will be apparent to those skilled in the art that the materials and methods used in the present application are well known in the art if not specifically described herein.

[0080] Example 1

[0081] This example is used to illustrate the large size rejuvenated amorphous alloy and its preparation method.

[0082] The alloy composition selected in this example is Zr 46 Cu 46 Al8(at. %), and the specific implementation steps are as follows:

[0083] (1) Pure metals Zr, Cu and Al with purity more than 99.9% are used to prepare the materials according to the nominal composition (at. %), and then put into a vacuum arc furnace for melting 5 times to obtain a master alloy ingot with a mass of about 20 g. Then the ingot is put into an arc furnace for remelting, and the melt is sucked into a water-cooled copper mold under a pressure difference of 10 4 Pa. Since Zr 46 Cu 46 The glass forming ability of the Al8alloy is good, and generally an amorphous alloy rod with a diameter of 7 mm can be prepared. In order to ensure that the obtained alloy is completely amorphous, the copper mold with a diameter of 5 mm is selected in this example, and finally an as-cast amorphous alloy rod with a diameter of 5 mm is obtained.

[0084] (2) The lathe processing method is used to prepare the sample according to the nominal composition (at. %) of the alloy, and the sample is then placed in a vacuum arc furnace for melting 5 times to obtain a master alloy ingot with a mass of about 20 g. Then the ingot is put into an arc furnace for remelting, and the melt is sucked into a water-cooled copper mold under a pressure difference of 10 Figure 2Processing gradient cylinder, the ratio of the end size (a) and middle size (b) of the sample with size gradient is 0.89;

[0085] (3) The gradient cylinder in step (2) was fully loaded using a universal mechanical testing machine. Uniaxial quasi-static compression was used with a strain rate of 5*10 -4 s -1 , full load stress is 2045MPa(σ UCS ), full load time is 5min, such as Figure 3 shown.

[0086] (4) The sample after the full loading treatment in step (3) was cut into a rectangular slice (named as rejuvenation sample 1) with a length of 3 mm, a width of 3 mm, and a thickness of 0.7 mm in the middle area of ​​the gradient cylinder (with a diameter of 4.5 mm) by diamond wire cutting. At the same time, a slice of the same size was cut into a slice (named as-cast sample 1) by diamond wire cutting from the amorphous alloy rod obtained in step (1);

[0087] (5) Using X-ray diffraction technology, measure the X-ray diffraction spectra of the rejuvenation sample 1 and the cast sample 1 in step (4).

[0088] (6) Using a differential scanning calorimeter, measure the heat flow versus temperature curves of the rejuvenated sample 1 and the as-cast sample 1 in step (4) in a temperature range of 50 to 550°C at a heating rate of 20 K / min. Obtain the heat flow versus temperature curves, and calculate the corresponding relaxation enthalpy (ΔH) according to formula (1);

[0089]

[0090] Where ΔH is the relaxation enthalpy, c p is the specific heat of the alloy, RT is room temperature, and T1 is the temperature near the glass transition point at which the specific heat of the alloy is equal to the specific heat at room temperature. In this embodiment, T1 of the as-cast sample 1 is 682.6 K, and T1 of the rejuvenated sample 1 is 718.7 K.

[0091] (7) The as-cast amorphous alloy rod obtained in step (1) was lathe-processed to obtain a cylinder with a diameter of 2 mm and a height of 4 mm (named as-cast sample 2);

[0092] (8) The gradient cylinder after the full loading treatment in step (4) is pressed Figure 4 Processed into a cylinder with a diameter of 2 mm and a height of 4 mm (named rejuvenation sample 2);

[0093] (9) The compression properties of the rejuvenation sample 2 and the cast sample 2 in steps (7) and (8) were tested using a universal mechanical testing machine. The compression strain rate was 5*10 -4 s -1 .

[0094] Figure 5 For the X-ray diffraction spectra of the as-cast sample 1 and the annealed sample 1, it is obvious that both the as-cast and the annealed samples show a typical "dumpling peak", proving that both states are completely amorphous. After the saturation treatment of the gradient cylinder, the middle region (4.5 mm in diameter) of the gradient cylinder has undergone a severe annealing transition, which can be evaluated by the relaxation enthalpy (ΔH) corresponding to the heat flow curve. As shown in FIG. 1, the area of the shaded part in the figure is the relaxation enthalpy. The ΔH of the as-cast sample is 0.108 kJ / mol, and the ΔH of the annealed sample is 3.231 kJ / mol. It is obvious that the relaxation enthalpy of the annealed state is greatly improved compared with the as-cast state. Moreover, the relaxation enthalpy of the amorphous alloy obtained by the method is also significantly greater than the result of the prior art (ΔH < 1.6 kJ / mol). That is, the sample treated by the method has undergone a severe annealing, and the size corresponding to the annealing in this embodiment is 4 mm, which is much larger than the size in the prior art (< 2 mm). Figure 6

[0095] Figure 7 By comparing the compression engineering stress-strain curves of the as-cast and the annealed samples, the plastic strain of the as-cast sample is about 1.9%, while the plastic strain of the annealed sample can reach 17.9%. The room temperature plasticity of the alloy is greatly improved in the annealed state compared with the as-cast state, significantly improving the original brittleness of the amorphous alloy. Moreover, the improvement of the room temperature plasticity of the amorphous alloy by the method is also much higher than that of the prior art (< 8%).

[0096] From the above data, it can be seen that the present application breaks the mutual restriction relationship between the volume and the annealing degree, and realizes the largest size and the largest degree of annealing. Moreover, the sample after annealing shows very excellent room temperature plasticity, and therefore, the method lays a solid foundation for the practical engineering application of the amorphous alloy.

[0097] Example 2

[0098] This embodiment is used to illustrate the large-size annealed amorphous alloy and the preparation method thereof.

[0099] The alloy composition selected in this embodiment is Zr 52.5 Ti5Cu 17.9 Ni 14.6 Al 10 (Vit105) (atomic percentage), and the specific implementation steps are as follows:

[0100] ​(1) Using pure metals Zr, Ti, Cu, Ni and Al with a purity exceeding 99.9%, the materials were prepared according to the nominal composition (atomic percentage), and then smelted in a vacuum arc furnace for 6 times to obtain a master alloy ingot with a mass of about 15g. The ingot was then remelted in an arc furnace at 2*10 4 The melt was sucked into a water-cooled copper mold under a pressure difference of Pa, and finally a cast amorphous alloy square column with a side length of 3 mm was obtained;

[0101] (2) Using wire cutting method according to Figure 8 Processing gradient square columns, the ratio of the end size (a) to the middle size (b) of the size gradient sample is 0.83;

[0102] (3) The gradient square column in step (2) was fully loaded using a universal mechanical testing machine. Uniaxial quasi-static compression was used with a strain rate of 5*10 -3 s -1 , full load stress is 1920MPa(1.1σ y ), full load time is 10min;

[0103] (4) The sample after the full loading treatment in step (3) was cut into a rectangular slice with a length of 2.5 mm, a width of 2.5 mm, and a thickness of 0.7 mm in the middle area of ​​the gradient square prism by diamond wire cutting (named as rejuvenation sample 3). At the same time, a slice of the same size was cut into a slice (named as-cast sample 3) by diamond wire cutting on the amorphous alloy square prism obtained in step (1);

[0104] (5) Using a differential scanning calorimeter, the heat flow versus temperature curves of the rejuvenated sample 3 and the as-cast sample 3 in step (4) were measured in a temperature range of 50 to 550°C at a heating rate of 20 K / min. The heat flow versus temperature curves were obtained, and the corresponding relaxation enthalpy (ΔH) was calculated according to formula (1);

[0105] The ΔH of the as-cast sample 3 is 0.164 kJ / mol, and the ΔH of the rejuvenated sample 3 is 2.478 kJ / mol. Figure 9 That is, the samples treated by this method underwent a dramatic rejuvenation. Figure 10 Comparing the compressive engineering stress-strain curves of the as-cast and rejuvenated samples, the plastic strain of the as-cast sample was approximately 3.3%, while the plastic strain of the rejuvenated sample reached 15.4%. Clearly, the room-temperature plasticity of the amorphous alloy was significantly improved after the rejuvenation treatment, significantly alleviating its original brittleness.

[0106] Matters not covered in the present invention are common knowledge.

[0107] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made in accordance with the spirit of the present invention are intended to be covered by the scope of protection of the present invention.

[0108] Although the present invention has been described to a certain extent, it is obvious that appropriate changes in various aspects can be made without departing from the spirit and scope of the present invention. It is understood that the present invention is not limited to the embodiments described, but belongs to the scope of the claims, which includes equivalent replacements of each factor described.

Claims

1. A method for preparing a rejuvenated amorphous alloy, characterized in that: The method comprises the following steps: (1) preparing cast amorphous alloy; (2) processing the cast amorphous alloy prepared in step (1) into a sample with a size gradient, wherein the ratio of the end size to the middle size of the sample with the size gradient is 0.7 to 1.0; (3) subjecting the size gradient sample prepared in step (2) to full loading treatment to obtain a rejuvenated amorphous alloy; in: The cross-sectional diameter or side length of the rejuvenated amorphous alloy is 1 to 15 mm, and the plastic strain of the rejuvenated amorphous alloy is ≥5%; The amorphous alloy is selected from the following alloy systems composed of elements: Zr-Cu-Al system, Zr-Cu-Ni-Al system, Cu-Zr-Ti-Hf system, Pd-Ni-P system, Pd-Cu-Ni-P system, Fe-Cr-Co-Mo-Mn-CBY amorphous steel system, La-Al-Ni system; In the step (3), the full load treatment method is quasi-static uniaxial compression or quasi-static uniaxial tension, the full load treatment method is quasi-static uniaxial compression, and the strain rate of the quasi-static uniaxial compression is 10 -6 s -1 ~10 -2 s -1 The full load time of the quasi-static uniaxial compression is 1 to 60 minutes, and the full load stress of the quasi-static uniaxial compression depends on the yield strength and maximum compressive strength of the cast amorphous alloy. The full load stress is 0.9σ y ~σ UCS and / or 500MPa<σ y <5000MPa、550MPa<σ UCS <5500Mpa, where σ y is the yield strength of the amorphous alloy, σ UCS is the maximum compressive strength of the amorphous alloy.

2. The method according to claim 1, characterized in that The cross-sectional diameter or side length of the rejuvenated amorphous alloy is 2 to 12 mm, and the plastic strain of the rejuvenated amorphous alloy is ≥10%.

3. The method according to claim 2, characterized in that The cross-sectional diameter or side length of the rejuvenated amorphous alloy is 4 to 10 mm, and the plastic strain of the rejuvenated amorphous alloy is ≥15%.

4. The method according to claim 3, characterized in that The plastic strain of the rejuvenated amorphous alloy is ≥17%.

5. The method according to claim 1, wherein The amorphous alloy is selected from the following alloy systems composed of elements: Zr-Cu-Al system, Zr-Cu-Ni-Al system, Cu-Zr-Ti-Hf system, Pd-Cu-Ni-P system, and Fe-Cr-Co-Mo-Mn-CBY amorphous steel system.

6. The method according to claim 5, characterized in that The amorphous alloy is selected from the following alloy systems composed of elements: Zr-Cu-Al system, Zr-Cu-Ni-Al system, Cu-Zr-Ti-Hf system, and Fe-Cr-Co-Mo-Mn-CBY amorphous steel system.

7. The method according to any one of claims 1 to 6, characterized in that The shape of the cast amorphous alloy is selected from one or more of the following: cylindrical rods, square columns, and blocks of any other shapes.

8. The method according to claim 7, characterized in that The cast amorphous alloy is in the shape of a cylindrical rod or a square column.

9. The method according to claim 8, characterized in that The cast amorphous alloy is in the shape of a cylindrical rod.

10. The method according to any one of claims 1 to 6, characterized in that The rejuvenation degree of the rejuvenated amorphous alloy is characterized by the magnitude of the relaxation enthalpy; wherein, The relaxation enthalpy is calculated by formula (1): Where ΔH is the relaxation enthalpy, c p is the specific heat capacity of the alloy, RT is room temperature, and T1 is the temperature point near the glass transition point where the specific heat capacity of the alloy is the same as that at room temperature.

11. The method according to claim 10, characterized in that The relaxation enthalpy is 0.2 to 4 kJ / mol.

12. The method according to claim 11, characterized in that The relaxation enthalpy is 2 to 4 kJ / mol.

13. The method according to claim 12, characterized in that The relaxation enthalpy is 3-4 kJ / mol.

14. The method according to any one of claims 1 to 6, characterized in that The step (1) further comprises the following steps: (A) preparing materials according to atomic percentages of pure metals, smelting, and cooling to obtain a master alloy ingot; (B) remelting the master alloy ingot prepared in step (A) to obtain the cast amorphous alloy; Wherein, the step (B) further comprises: after re-melting, sucking the melt into a water-cooled copper mold under a pressure difference to obtain the cast amorphous alloy.

15. The method according to claim 14, characterized in that: In step (A), the purity of the pure metal is 99.9% to 99.999%; and / or In the step (B), the pressure difference is 10 3 ~10 5 Pa.

16. The method according to claim 15, characterized in that In the step (B), the pressure difference is 10 4 ~5*10 4 Pa.

17. The method according to claim 16, characterized in that In the step (B), the pressure difference is 2*10 4 ~3*10 4 Pa.

18. The method according to any one of claims 1 to 6, characterized in that In the step (2), the processing method is selected from the following: lathe processing, wire cutting, and spray casting.

19. The method according to claim 18, characterized in that In the step (2), the processing method is lathe processing or wire cutting.

20. The method according to claim 19, characterized in that In the step (2), the processing method is lathe processing.

21. The method according to any one of claims 1 to 6, characterized in that In the step (2), the ratio of the two end sizes to the middle size of the sample with the size gradient is 0.8 to 0.

95.

22. The method according to claim 21, characterized in that In the step (2), the ratio of the two end dimensions to the middle dimension of the sample with the size gradient is 0.8 to 0.

9.

23. The method according to any one of claims 1 to 6, characterized in that In the step (3): The strain rate of the quasi-static uniaxial compression is 10 -6 s -1 ~10 -3 s -1 and / or The full load time of the quasi-static uniaxial compression is 1 to 30 minutes.

24. The method according to claim 23, wherein In the step (3): The strain rate of the quasi-static uniaxial compression is 10 -4 s -1 ~10 -3 s -1 and / or The full load time of the quasi-static uniaxial compression is 3 to 10 minutes.

25. The method according to any one of claims 1 to 6, characterized in that In the step (3): The full load stress is σ y ~σ UCS and / or 1000MPa<σ y <3500MPa,1050MPa<σ UCS <3800MPa。 26. The method according to claim 25, characterized in that In the step (3): The full load stress is 1.1σ y ~σ UCS and / or 1500MPa<σ y <3000MPa,1700MPa<σ UCS <3200MPa。

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