High-toughness metal / amorphous refractory high-entropy alloy and preparation method thereof

Abstract

The invention discloses a high-toughness metal / amorphous refractory high-entropy alloy and a preparation method thereof, and belongs to the field of material surface modification.The multi-layer film comprises TaWMoCrZr layers and Zr layers which are alternately arranged, and the TaWMoCrZr layers and the Zr layers of all modulation periods are the same in thickness; the TaWMoCrZr layer is of a high-entropy amorphous structure, Zr is of a crystal structure of HCP, and a crystal and amorphous interface structure is arranged between the TaWMoCrZr layer and the Zr layer; according to the multi-layer film, the microstructure of the multi-layer film is regulated and controlled through a magnetron sputtering method, the mechanical property is improved by controlling the limiting and coordinating effect between the grain size and a heterogeneous phase structure, and the high-toughness metal / amorphous refractory high-entropy alloy multi-layer film has great significance for prolonging the service life of a material under the extreme service condition.

Description

Technical Field

[0001] The present invention relates to the field of material surface modification, and in particular to a high-strength and toughness metal / amorphous refractory high-entropy alloy and a preparation method thereof. Background Art

[0002] In modern materials science and engineering, the demand for high-temperature application materials is growing rapidly with the rapid development of high-end industries such as aerospace, energy and power, and the nuclear industry. Refractory metals, such as tungsten (W), molybdenum (Mo), niobium (Nb), tantalum (Ta), and rhenium (Re), demonstrate tremendous potential in these demanding high-temperature applications due to their unique combination of properties: high melting points, excellent high-temperature strength, and exceptional thermal stability. They are widely considered key potential materials for the next generation of high-temperature applications.

[0003] However, the room temperature brittleness of refractory metals has long been a serious constraint on their engineering applications, becoming a key problem hindering their further development. The room temperature brittleness of refractory metals is mainly due to the characteristics of their crystal structure and electronic structure. Taking refractory metals with a body-centered cubic structure as an example, they have relatively few slip systems and face greater resistance to dislocation movement at room temperature, resulting in poor plastic deformation capacity. In addition, factors such as impurity elements, grain boundary structure, and microscopic defects in refractory metals also have a significant impact on their room temperature brittleness. Impurity elements may segregate at grain boundaries, weakening the bonding strength of the grain boundaries and reducing the toughness of the material; the structure and characteristics of the grain boundaries will affect the movement of dislocations and the slip of the grain boundaries, thereby affecting the plastic deformation capacity of the material; microscopic defects such as vacancies and dislocations can easily become sources of crack initiation under stress, accelerating the fracture process of the material.

[0004] Due to room temperature brittleness, refractory metals are prone to cracking and breaking during processing, resulting in low yields and increased production costs. In actual use, room temperature brittleness also makes refractory metal components prone to failure when subjected to unexpected impact or thermal shock, reducing system reliability and safety. Therefore, addressing the room temperature brittleness of refractory metals and improving their room temperature ductility are of great theoretical and practical significance for promoting their widespread use in high-temperature applications and promoting the development of related industries. Summary of the Invention

[0005] In response to the problems existing in the prior art, the present invention provides a high-strength and toughness metal / amorphous refractory high-entropy alloy and a preparation method thereof, which improves the mechanical properties of the refractory high-entropy alloy by regulating the microstructure of the refractory high-entropy alloy multilayer film.

[0006] The present invention is achieved through the following technical solutions: A high-strength and tough metal / amorphous refractory high-entropy alloy comprising alternating TaWMoCrZr layers and Zr layers, wherein the thickness of the TaWMoCrZr layers and the Zr layers in each modulation period are the same; The TaWMoCrZr layer has a high entropy amorphous structure, the Zr layer has a HCP crystal structure, and the interface structure between the TaWMoCrZr layer and the Zr layer is a crystal and amorphous structure.

[0007] Preferably, the atomic percentage ratio of each element in the TaWMoCrZr layer is 1:1:1:1:1.

[0008] Preferably, the thickness of the TaWMoCrZr layer and the Zr layer is 5-100 nm, and the thickness of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film is 1.6-5 μm.

[0009] Preferably, the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film has a nanoindentation hardness of 6~7GPa, a Young's modulus of 100~134GPa, and a ductility of 1.5%~2.2%.

[0010] A method for preparing a high-strength and tough metal / amorphous refractory high-entropy alloy comprises the following steps: Step 1: cleaning and vacuum etching the substrate; Step 2: Using a TaWMoCr alloy target and a Zr target, alternately sputter-depositing TaWMoCrZr layers and Zr layers on the vacuum-etched substrate until a predetermined thickness is reached to obtain a multilayer film; The TaWMoCrZr layer is co-sputtered by a TaWMoCr alloy target and a Zr target. The DC power of the TaWMoCr alloy target is 200W, the DC power of the Zr target is 100W, and the deposition time of the TaWMoCrZr layer is 32-625s. When the Zr layer is deposited by sputtering, the DC power of the Zr target is 200W, and the deposition time of the Zr layer is 33-667s; Step 3: Cool the multilayer film to room temperature to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film.

[0011] Preferably, during the sputtering deposition process in step 3, the deposition gas pressure is 0.3 Pa and the substrate rotation speed is 15 r / min.

[0012] Preferably, the cleaning method of the substrate in step 1 is as follows: The polished substrate was ultrasonically cleaned in acetone and anhydrous ethanol respectively and then dried to remove impurities on the substrate surface.

[0013] Preferably, the etching method of the substrate in step 1 is as follows: The cleaned substrate is etched under vacuum conditions with an etching power of 200 W, an etching pressure of 1.0 Pa, and an etching time of 5-10 min.

[0014] Preferably, the cooling time in step 3 is 2-3 hours.

[0015] Preferably, the substrate is a steel substrate or a single crystal silicon substrate.

[0016] Compared with the prior art, the present invention has the following beneficial technical effects: The present application provides a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film. Due to the presence of a dual-phase structure of amorphous and crystalline layers and the effect of the crystalline / amorphous interface, it can better coordinate plastic deformation, making the multilayer film material have a certain ductility while maintaining excellent thermal stability and high strength. The high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film has a uniform microstructure, good corrosion and oxidation resistance, radiation resistance, and excellent high-temperature structural stability and mechanical properties.

[0017] The present application prepares a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film by depositing it on a clean silicon substrate through a magnetron sputtering deposition method. During the preparation process, the microstructure of the high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film is regulated by controlling the modulation period, and the mechanical properties are improved by controlling the restrictive coordination between the grain size and the heterogeneous phase structure, thereby obtaining a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with uniform distribution of alloy elements, different microstructures and excellent performance. While maintaining high strength and high thermal stability, the multilayer film also has a certain ductility. The high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film is of great significance to improving the service life of materials under extreme service conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 This is the XRD result diagram of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film of the present invention.

[0020] Figure 2 These are the TEM low-magnification morphology images, selected area electron diffraction and high-resolution images of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film of the present invention.

[0021] Figure 3This is the indentation hardness diagram of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film of the present invention. Figure 4 This is a diagram showing the micro-tensile results of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film of the present invention.

[0022] Figure 5 These are the STEM photos and EDS element distribution maps of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film of the present invention. DETAILED DESCRIPTION

[0023] To make the objectives, technical solutions, and advantages of the embodiments of the present application more clear, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Generally, the components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0024] Therefore, the following detailed description of the embodiments of the present application provided in the accompanying drawings is not intended to limit the scope of the present application for protection, but merely represents selected embodiments of the present application. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments in the present application without creative work are within the scope of protection of the present application.

[0025] A high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film, comprising alternating TaWMoCrZr layers and Zr layers, wherein the thickness of the TaWMoCrZr layers and the Zr layers in each modulation period are the same; The TaWMoCrZr layer has a high entropy amorphous structure, the Zr layer has a HCP crystal structure, and the interface structure between the TaWMoCrZr layer and the Zr layer is a crystal and amorphous structure.

[0026] In the TaWMoCrZr refractory high entropy amorphous layer, the atomic percentage ratio of the five elements Ta, W, Mo, Cr and Zr is 1:1:1:1:1.

[0027] The high-entropy amorphous layer has a uniform and stable structure, without obvious clusters or element segregation. The crystalline layer exists in the form of nanocrystals. The interface is clear and straight, and the elements are evenly distributed.

[0028] The modulation ratio of the TaWMoCrZr layer and the Zr layer is 1, the thickness of the TaWMoCrZr layer and the Zr layer is 5-100 nm, and the thickness of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film is 1.6-5 μm.

[0029] The high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film has a nanoindentation hardness of 6-7 GPa, a Young's modulus of 100-134 GPa, and a ductility of 1.5%-2.2%.

[0030] The present application provides a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film, which regulates the interface density of the high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film by controlling the modulation period. The TaWMoCrZr layer is a high-entropy amorphous structure, combining the advantages of high entropy and amorphous to provide excellent strength and stability for the material. Zr is a crystalline structure of HCP and exists in the multilayer film in the form of nanocrystals, providing excellent strong plasticity for the material. A heterogeneous interface is formed between the amorphous layer and the crystalline layer. The crystal / amorphous interface has a certain strain compatibility. During the plastic deformation process, when the dislocations in the crystal layer slip to the interface, it promotes the activation of the shear transition zone in the amorphous. The two heterogeneous structures interact with each other and affect the plastic deformation of the multilayer film together with the crystal / amorphous interface. The element Zr in the high-entropy amorphous layer is selected as the crystal layer to provide good chemical compatibility for the crystal / amorphous interface, achieve strong interface bonding, give full play to the coordination effect of the interface, and promote the improvement of mechanical properties. The coordinated plastic deformation under the joint action of the two-phase structure and the interface makes the multilayer film material have a certain ductility while maintaining excellent strength, achieving the design goal of high strength and toughness.

[0031] Correspondingly, the present application also provides a method for preparing the above-mentioned high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film, comprising the following steps: Step 1: Clean the substrate to remove impurities and oxide film on the surface; Specifically, the substrate is a steel substrate or a single crystal silicon substrate.

[0032] The polished substrate was ultrasonically cleaned in acetone and anhydrous ethanol for 15 min respectively and then dried to remove impurities on the substrate surface.

[0033] Step 2: vacuum-etching the substrate obtained in step 1.

[0034] Specifically, the etching power is 200W, the etching pressure is 1.0Pa, the etching time is 5min, and the back vacuum is 4.0×10 -4 Below Pa.

[0035] Step 3: Using a TaWMoCr alloy target and a Zr target, alternately sputter-deposit TaWMoCrZr layers and Zr layers on the vacuum-etched substrate until a predetermined thickness is reached to obtain a multilayer film.

[0036] Specifically, first, a TaWMoCr alloy target and a Zr target are co-sputtered to deposit a TaWMoCrZr layer, and then a Zr target is sputtered to deposit a Zr layer, and the TaWMoCrZr layer and the Zr layer are repeated until a predetermined thickness is reached.

[0037] When the TaWMoCrZr layer is co-sputtered, the DC power of the TaWMoCr alloy target is 200W, and the DC power of the Zr target is 100W. When the Zr layer is sputtered, the DC power of the Zr target is 200W.

[0038] The deposition gas pressure was 0.3 Pa, the substrate rotation speed was 15 r / min, and the deposition time of the TaWMoCrZr layer in each sputtering cycle was 32 to 625 s, and the deposition time of the Zr layer was 33 to 667 s.

[0039] Step 4: Cool the multilayer film to room temperature to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film.

[0040] Specifically, after deposition, the multilayer film is fully cooled to room temperature in a high vacuum coating chamber before being taken out to prevent debonding and cracking caused by the difference in thermal expansion coefficients between the substrate and the coating material, and to prevent oxidation with air due to high temperature.

[0041] The present application prepares a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film by depositing it on a clean silicon substrate through magnetron sputtering deposition. Taking advantage of the magnetron sputtering technology, a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with uniform distribution of alloy elements and excellent performance is prepared. The design selects Ta, W, Mo, Cr, and Zr as the component components of the nano multilayer film to prepare a refractory high-entropy amorphous layer - TaWMoCrZr, and a crystalline layer - Zr, which provide good thermal stability and high strength for the nano multilayer film and better serve in high-temperature environments. The two heterogeneous structures of crystal and amorphous form a compatible crystal / amorphous interface, which promotes the coordinated deformation of the two, increases the ductility of the multilayer film, and realizes the strengthening and toughening of the multilayer film.

[0042] Example 1 A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 1: The polished steel substrate is ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes respectively and then dried to remove impurities on the substrate surface.

[0043] Step 2: Fix the steel substrate obtained in step 1 to the base plate with conductive glue, mechanically transport it into the coating chamber, and evacuate it to 4.0×10 -4 Pa or less, using Ar + Ion-pair etching was performed on the substrate to further remove impurities on the substrate surface. The etching power was 200 W, the etching pressure was 1.0 Pa, and the etching time was 5 min.

[0044] Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 32s. Then, a Zr layer was deposited by sputtering using a Zr target, the DC power of the Zr target was 200 W, and the deposition time was 33 s.

[0045] The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0046] Finally, TaWMoCrZr layer and Zr layer were repeatedly sputtered and deposited for 200 sputtering cycles to obtain a multilayer film. The thickness of each TaWMoCrZr layer and Zr layer was 5 nm, and the total thickness of the multilayer film was 2 μm.

[0047] Step 4: The multilayer film is naturally cooled in a vacuum coating chamber for 2 hours to room temperature and then taken out to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with a thickness of about 2 μm.

[0048] Example 2 A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 1: The polished silicon substrate is ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes respectively and then dried to remove impurities on the substrate surface.

[0049] Step 2: The silicon substrate obtained in step 1 is fixed to the base plate with conductive glue, mechanically transported into the coating chamber, and vacuumed to 4.0×10 -4 Pa or less, using Ar + Ion-pair etching is performed on the substrate to further remove impurities on the substrate surface. The etching power is 200 W, the etching pressure is 1.0 Pa, and the etching time is 8 min.

[0050] Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 64s. Then, a Zr layer was deposited by sputtering using a Zr target, with a DC power of 200 W and a deposition time of 66 s. The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0051] Finally, TaWMoCrZr layer and Zr layer were repeatedly sputtered and deposited for 100 sputtering cycles to obtain a multilayer film. The thickness of each TaWMoCrZr layer and Zr layer was 10 nm, and the total thickness of the multilayer film was 2 μm.

[0052] Step 4: The multilayer film is naturally cooled in a vacuum coating chamber for 3 hours to room temperature and then taken out to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with a thickness of about 2 μm.

[0053] Example 3 A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 1: The polished silicon substrate is ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes respectively and then dried to remove impurities on the substrate surface.

[0054] Step 2: The silicon substrate obtained in step 1 is fixed to the base plate with conductive glue, mechanically transported into the coating chamber, and vacuumed to 4.0×10 -4 Pa or less, using Ar + Ion-pair etching is performed on the substrate to further remove impurities on the substrate surface. The etching power is 200 W, the etching pressure is 1.0 Pa, and the etching time is 10 min.

[0055] Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 156s. Then, a Zr layer was deposited by sputtering using a Zr target, with a DC power of 200 W and a deposition time of 165 s. The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0056] Finally, TaWMoCrZr layer and Zr layer were repeatedly sputtered and deposited for 40 sputtering cycles to obtain a multilayer film. The thickness of each TaWMoCrZr layer and Zr layer was 25 nm, and the total thickness of the multilayer film was 2 μm.

[0057] Step 4: The multilayer film is naturally cooled in a vacuum coating chamber for 3 hours to room temperature and then taken out to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with a thickness of about 2 μm.

[0058] Example 4 A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 1: The polished steel substrate is ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes respectively and then dried to remove impurities on the substrate surface.

[0059] Step 2: Fix the steel substrate obtained in step 1 to the base plate with conductive glue, mechanically transport it into the coating chamber, and evacuate it to 4.0×10 -4 Pa or less, using Ar + Ion-pair etching was performed on the substrate to further remove impurities on the substrate surface. The etching power was 200 W, the etching pressure was 1.0 Pa, and the etching time was 5 min.

[0060] Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 312s. Then, a Zr layer was deposited by sputtering using a Zr target, with a DC power of 200 W and a deposition time of 334 s. The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0061] Finally, TaWMoCrZr and Zr layers were repeatedly sputtered and deposited for 20 sputtering cycles to obtain a multilayer film. The thickness of each TaWMoCrZr and Zr layer was 50 nm, and the total thickness of the multilayer film was 2 μm.

[0062] Step 4: The multilayer film is naturally cooled in a vacuum coating chamber for 2.5 hours to room temperature and then taken out to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with a thickness of about 2 μm.

[0063] Example 5 A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 1: The polished steel substrate is ultrasonically cleaned in acetone and anhydrous ethanol for 15 minutes respectively and then dried to remove impurities on the substrate surface.

[0064] Step 2: Fix the steel substrate obtained in step 1 to the base plate with conductive glue, mechanically transport it into the coating chamber, and evacuate it to 4.0×10 -4 Pa or less, using Ar + Ion-pair etching was performed on the substrate to further remove impurities on the substrate surface. The etching power was 200 W, the etching pressure was 1.0 Pa, and the etching time was 5 min.

[0065] Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 625s. Then, a Zr layer was deposited by sputtering using a Zr target, with a DC power of 200 W and a deposition time of 667 s. The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0066] Finally, TaWMoCrZr layer and Zr layer were repeatedly sputtered and deposited, and the number of sputtering cycles was 10 to obtain a multilayer film. The single layer thickness of TaWMoCrZr layer and Zr layer was 100 nm, and the total film thickness of the multilayer film was 2 μm.

[0067] Step 4: The multilayer film is naturally cooled in a vacuum coating chamber for 2.5 hours to room temperature and then taken out to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film with a thickness of about 2 μm.

[0068] Example 6 The difference between this embodiment and embodiment 1 lies in the deposition time and the number of sputtering cycles in step 3. The rest of the process is the same, as follows: A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 32s. Then, a Zr layer was deposited by sputtering using a Zr target, the DC power of the Zr target was 200 W, and the deposition time was 33 s.

[0069] The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0070] Finally, TaWMoCrZr and Zr layers were repeatedly sputtered and deposited for 160 sputtering cycles to obtain a multilayer film. The thickness of each TaWMoCrZr and Zr layer was 5 nm, and the total thickness of the multilayer film was 1.6 μm.

[0071] Example 7 The difference between this embodiment and embodiment 5 lies in the deposition time and the number of sputtering cycles in step 3. The rest of the process is the same, as follows: A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film comprises the following steps: Step 3: First, TaWMoCrZr layer was co-sputtered using TaWMoCr alloy target and Zr target. The DC power of TaWMoCr alloy target was 200W, the DC power of Zr target was 100W, and the deposition time was 625s. Then, a Zr layer was deposited by sputtering using a Zr target, with a DC power of 200 W and a deposition time of 667 s. The deposition pressure of the TaWMoCrZr layer and the Zr layer was 0.3 Pa, and the substrate rotation speed was 15 r / min.

[0072] Finally, TaWMoCrZr and Zr layers were repeatedly sputtered and deposited, with the number of sputtering cycles being 25, to obtain a multilayer film. The thickness of each TaWMoCrZr and Zr layer was 100 nm, and the total thickness of the multilayer film was 5 μm.

[0073] Figure 1The XRD results of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer films prepared in Examples 1-5 show that the crystal peak of Zr can be observed.

[0074] Figure 2 The following are TEM low-magnification morphology images, selected area electron diffraction (SAED), and high-resolution images of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film prepared in Example 2. The HEA layer is observed to be amorphous with a small amount of BCC phase crystals. The Zr layer is nanocrystalline with an HCP structure.

[0075] Figure 3 This is the indentation hardness diagram of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film of the present invention. The indentation hardness at different layer thicknesses exceeds 6 GPa, showing high hardness and strength.

[0076] Figure 4 This is the micro-tensile result of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film prepared in Example 4, which can reach a critical strain of 2.2%, which is greatly improved compared to the room temperature brittleness of other refractory metals.

[0077] Figure 5 The STEM image and EDS element distribution map of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film prepared in Example 4. The elements are evenly distributed in the structure, the interface is clear and straight, and it has excellent mechanical properties and stability.

[0078] The present application discloses a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film, in which Ta, W, Mo, Cr, and Zr are selected as the components of the nano-multilayer film. The Zr alloy has the characteristics of small thermal neutron capture cross section, good corrosion resistance, and excellent mechanical properties, and is widely used in fuel cladding tubes and structural components in the nuclear industry. High-entropy amorphous alloys, also known as high-entropy metallic glasses, combine the compositional characteristics of high-entropy alloys with the structural characteristics of long-range disorder of metallic glasses. They have high hardness, strength, elastic limit, good thermal stability and corrosion resistance, and have been a research hotspot in recent years. In order to better meet the service requirements of high-temperature environments, the high-entropy alloy coating elements should be selected from refractory metals to give the material excellent thermodynamic properties.

[0079] Secondly, the TaWMoCrZr layer has a high-entropy amorphous structure, while the Zr layer has a HCP crystalline structure. This creates a heterogeneous structure between the amorphous and crystalline layers. This heterogeneous structure (HS) consists of heterogeneous regions with varying (>100%) mechanical or physical properties. The interaction and coupling between these heterogeneous regions creates a synergistic effect, significantly enhancing the material's performance. HS materials possess exceptional mechanical and physical properties unattainable by traditional homogeneous materials. Heterogeneous multilayer structures are gaining increasing attention due to their vast tunability and superior performance, becoming an effective path to overcome the room-temperature brittleness of refractory metals.

[0080] In addition, due to its low energy, controllable deposition rate and good process repeatability, this application adopts magnetron sputtering to prepare nano-multilayer films with heterogeneous structures. By regulating the layer thickness through controlling the preparation process, the influence of the size effect of the multilayer film structure on the performance is explored, providing an effective solution for improving the ductility of refractory metals, realizing the regulation of the microstructure of high-strength and tough metal / amorphous refractory high-entropy alloy multilayer films, and improving their mechanical properties.

[0081] The above content is only for explaining the technical idea of the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A high-strength and tough metal / amorphous refractory high-entropy alloy, characterized in that: The method comprises alternating TaWMoCrZr layers and Zr layers, wherein the thickness of the TaWMoCrZr layers and the Zr layers in each modulation period are the same; The TaWMoCrZr layer has a high entropy amorphous structure, the Zr layer has a HCP crystal structure, and the interface structure between the TaWMoCrZr layer and the Zr layer is a crystal and amorphous structure.

2. The high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 1, characterized in that: The atomic percentage ratio of each element in the TaWMoCrZr layer is 1:1:1:1:

1.

3. The high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 1, characterized in that: The thickness of the TaWMoCrZr layer and the Zr layer is 5-100 nm, and the thickness of the high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film is 1.6-5 μm.

4. The high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 1, characterized in that: The high-strength and toughness metal / amorphous refractory high-entropy alloy multilayer film has a nanoindentation hardness of 6-7 GPa, a Young's modulus of 100-134 GPa, and a ductility of 1.5%-2.2%.

5. A method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step 1: cleaning and vacuum etching the substrate; Step 2: Using a TaWMoCr alloy target and a Zr target, alternately sputter-depositing TaWMoCrZr layers and Zr layers on the vacuum-etched substrate until a predetermined thickness is reached to obtain a multilayer film; The TaWMoCrZr layer is co-sputtered by a TaWMoCr alloy target and a Zr target. The DC power of the TaWMoCr alloy target is 200W, the DC power of the Zr target is 100W, and the deposition time of the TaWMoCrZr layer is 32-625s. When the Zr layer is deposited by sputtering, the DC power of the Zr target is 200W, and the deposition time of the Zr layer is 33-667s; Step 3: Cool the multilayer film to room temperature to obtain a high-strength and tough metal / amorphous refractory high-entropy alloy multilayer film.

6. The method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 5, characterized in that: During the sputtering deposition process in step 3, the deposition gas pressure was 0.3 Pa and the substrate rotation speed was 15 r / min.

7. The method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 5, characterized in that: The cleaning method of the substrate in step 1 is as follows: The polished substrate was ultrasonically cleaned in acetone and anhydrous ethanol respectively and then dried to remove impurities on the substrate surface.

8. The method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 5, characterized in that: The etching method of the substrate in step 1 is as follows: The cleaned substrate is etched under vacuum conditions with an etching power of 200 W, an etching pressure of 1.0 Pa, and an etching time of 5-10 min.

9. The method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 5, characterized in that: The cooling time in step 3 is 2-3 hours.

10. The method for preparing a high-strength and toughness metal / amorphous refractory high-entropy alloy according to claim 5, characterized in that: The substrate is a steel substrate or a single crystal silicon substrate.

Images