A NiAl alloy full-lamellar microstructure and its preparation method

Abstract

This invention belongs to the field of non-equilibrium solidification technology, specifically relating to a NiAl alloy full-lamellar microstructure and its preparation method. The method includes the following steps: (1) preparing a NiAl-based alloy ingot; (2) constructing the NiAl-based alloy ingot into a high-pressure assembly; (3) placing the high-pressure assembly in a heating chamber and performing high-pressure solidification treatment using a press to obtain a NiAl alloy full-lamellar microstructure containing high-density twins and stacking faults; the pressure of the high-pressure solidification treatment is 6-8 GPa, and the temperature of the high-pressure solidification treatment is 1500-1650℃. This invention achieves the construction of a full-lamellar microstructure and the introduction of high-density crystal defects simultaneously in a one-step process through high-pressure solidification. The resulting lamellar structure is rich in nanotwins and stacking faults at the interior and interface. These substructures can effectively hinder dislocation movement, passivate crack propagation, and significantly improve the toughness and deformation capacity of NiAl alloy while enhancing the material strength.

Description

Technical Field

[0001] This invention belongs to the field of non-equilibrium solidification technology, specifically relating to a NiAl alloy full-lamellar microstructure and its preparation method. Background Technology

[0002] NiAl-based alloys (including single-phase NiAl and two-phase NiAl-Ni3Al alloys) are a class of highly promising high-temperature structural materials with significant core advantages: excellent thermodynamic stability, with a stoichiometric ratio; the atmospheric melting point of NiAl is much higher than that of traditional Ni-based superalloys, making it suitable for high-temperature service environments; low density, only about 70% of that of traditional Ni-based superalloys, enabling lightweight design of aerospace components and improving equipment thrust and payload; and outstanding oxidation resistance, rapidly forming a dense Al2O3 oxide film in high-temperature environments, effectively blocking oxygen atom diffusion and reducing the risk of high-temperature corrosion failure. However, the industrial application of NiAl alloys has long been limited by their inherent defects. The core bottlenecks are poor room-temperature plasticity, low fracture toughness, and insufficient resistance to high-temperature creep. The alloy microstructure is extremely sensitive to compositional fluctuations and cooling rates, resulting in large performance dispersion, making it difficult to meet the stringent requirements for material stability in high-end equipment.

[0003] The NiAl-Ni3Al dual-phase lamellar microstructure is the optimal microstructure for solving the brittleness problem of NiAl alloys. This microstructure, through the alternating and continuous distribution of the NiAl hard phase (high strength) and the Ni3Al relatively tough phase (plastic buffer), can significantly improve the overall performance of the alloy by means of the mechanism of "fine lamellar strengthening, interface crack deflection, and dual-phase synergistic deformation". Existing preparation techniques are difficult to achieve the precise and stable preparation of NiAl alloy full lamellar microstructure. It is urgent to overcome the limitations of high-pressure solidification technology in the control of NiAl alloy full lamellar microstructure, establish a precise correlation between high-pressure parameters, full lamellar microstructure and properties, and solve the technical pain points of difficult formation of NiAl alloy full lamellar microstructure and poor performance synergy. It has important theoretical research value and engineering application prospects. Summary of the Invention

[0004] To address the aforementioned technical problems, the present invention aims to provide a method for preparing a fully lamellar NiAl alloy with high-density twins and stacking faults using high-pressure solidification. This method utilizes GPa-level high pressure as a means of controlling non-equilibrium solidification, achieving the co-generation of a fully lamellar structure and high-density crystal defects in one step. The process is simple and efficient, and the resulting material exhibits excellent comprehensive mechanical properties.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] A method for developing a fully lamellar microstructure of a NiAl alloy includes the following steps:

[0007] (1) Preparation of NiAl-based alloy ingots;

[0008] (2) The NiAl-based alloy ingot is combined with a boron nitride layer, a molybdenum sheet layer and a zirconium dioxide layer to form a high-pressure assembly. The boron nitride layer surrounds the periphery of the NiAl-based alloy ingot, the molybdenum sheet layer is placed above and below the boron nitride layer, and the zirconium dioxide layer covers the outer periphery of the boron nitride layer and the molybdenum sheet layer.

[0009] (3) The high-pressure assembly is placed in a heating chamber and subjected to high-pressure solidification treatment using a press to obtain a NiAl alloy full lamellar structure; the pressure of the high-pressure solidification treatment is 6-8 GPa, the temperature of the high-pressure solidification treatment is 1500-1650℃, and the NiAl alloy full lamellar structure is a NiAl alloy full lamellar structure containing high-density twins and stacking faults.

[0010] Furthermore, prior to the high-pressure solidification process, pyrophyllite is filled into the gap between the high-pressure assembly and the heating chamber.

[0011] Furthermore, before performing step (2), the NiAl-based alloy ingot is polished on 500-600 grit sandpaper.

[0012] Furthermore, before use, pyrophyllite is dried at 200-220℃ for 3-4 hours, and then stored at a constant temperature of 100-105℃ for later use.

[0013] Furthermore, the NiAl-based alloy ingot is prepared by electric arc melting.

[0014] Furthermore, the purity of the Al and Ni blocks used to prepare the NiAl-based alloy ingot is at least 99.99%.

[0015] Furthermore, the atomic percentage content of Ni in the NiAl-based alloy is 65-75 at.%, preferably 70 at.%.

[0016] Furthermore, the pressure of the high-pressure solidification treatment is 7 GPa.

[0017] Furthermore, the high-pressure solidification treatment temperature is 1600°C.

[0018] Furthermore, the heat preservation and pressure holding time for the high-pressure solidification treatment is 0.5-2 h, preferably 1 h.

[0019] Another objective of this invention is to provide a NiAl alloy full-lamellar microstructure material containing high-density twins and stacking faults prepared by the above method.

[0020] By implementing the above technical solution, compared with the prior art, the present invention has the following beneficial effects:

[0021] 1. This invention achieves the simultaneous construction of a full lamellar structure and the introduction of high-density crystal defects in a one-step process through high-pressure solidification. The resulting lamellar structures are rich in nanotwins and stacking faults at their interiors and interfaces. These substructures effectively hinder dislocation movement, passivate crack propagation, and coordinate plastic deformation through the "mirror" slip mechanism of the twin interfaces. This significantly improves the toughness and deformation capacity of NiAl alloys while enhancing strength, achieving a synergistic effect of "fine lamellar strengthening" and "twin / stacking fault toughening".

[0022] 2. The GPa-level high-pressure environment provides a unique and intense thermodynamic driving force for the extensive nucleation of twins and stacking faults, overcoming the limitations of atmospheric pressure or traditional heat treatment processes in introducing such controllable defects. High pressure not only regulates phase distribution to form full lamellar structures, but also directly affects atomic stacking behavior during solidification, actively inducing defect structures that are beneficial to performance optimization, thus achieving deep-level and multi-dimensional precise control of the alloy's microstructure.

[0023] 3. This invention combines full-layer microstructure design with high-pressure induced defect engineering, enabling NiAl alloys to move from "theoretically high performance" to "practically feasible applications." The resulting comprehensive microstructure, which combines good interfacial bonding, dense lamellar structure, and enhanced crystal defects, demonstrates the material's enormous application potential under extreme service environments such as high temperature, high pressure, and complex stress. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the arrangement of the high-pressure assembly in the heating cavity as shown in Embodiment 1 of the present invention.

[0025] Figure 2 The images are metallographic images of NiAl alloy under normal pressure and after high-pressure solidification, where a) is the metallographic image of NiAl alloy under normal pressure and b) is the metallographic image after high-pressure solidification at 7 GPa.

[0026] Figure 3 The results are TEM images of small-sized sheets: a) is a bright-field image of a small-sized sheet; b) is a bright-field image of different regions of the same size; c) is a surface scan of Al elements in image b); d) is a surface scan of Ni elements in image b.

[0027] Figure 4The TEM results are for large and medium-sized lamellae. a) is a bright-field image containing large, medium and small lamellae. b) is a SAED image of the large-sized region. c) is a dark-field image of the large-sized lamellae. d) is a dark-field image of the medium-sized lamellae. e) is a high-resolution image of the boundary between the large and medium-sized lamellae. f) is an FFT image of the twin region of the large lamellae. g) is a high-resolution image of the medium-sized lamellae. h) is an FFT image of the twin of the medium-sized lamellae. i) is an IFFT image obtained by inverse Fourier transform of the diffraction spots with the (100) crystal plane and the (200) crystal plane. j) is an IFFT image obtained by inverse Fourier transform of the (1 ̅1 ̅1) plane of another set of diffraction spots in the twin.

[0028] Figure 5 Mechanical property data obtained by performing nanoindentation experiments on the samples prepared by the methods of Comparative Example 1 and Example 1.

[0029] Figure 6 Ni-Al obtained under the same preparation method 10 Alloy, Ni-Al 15 Alloys and Ni-Al 40 Comparison of metallographic images of the alloys.

[0030] Figure 7 Scanning electron microscope (SEM) images of FeCoCrNiAlCu HEAs obtained by different preparation methods. Detailed Implementation

[0031] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.

[0032] This invention provides a method for preparing a fully lamellar NiAl alloy microstructure containing high-density twins and stacking faults by high-pressure solidification. The specific preparation method is as follows:

[0033] S1: Weigh appropriate amounts of aluminum (Al) and nickel (Ni) blocks, both with a purity of 99.99%, and clean and dry them for later use. Heat the blocks in an electric arc furnace until they melt, while simultaneously mixing the molten aluminum and nickel blocks evenly. After cooling, a sample is obtained. Cut the sample into round bars, and use 500-600 grit sandpaper to remove the cut marks. After cleaning and drying, an Al-Ni alloy sample is obtained. To improve the effect of the subsequently obtained high-pressure solidification material, the mass ratio of aluminum and nickel blocks during the melting and mixing process can be adjusted to maintain the Ni mass fraction in the obtained Al-Ni alloy sample at 65-75 at.

[0034] S2: The Al-Ni alloy sample is assembled into an assembly and placed in the heatable pressure chamber of a hydraulic press (i.e., the hammerhead section; a carbon heating element is installed on the inner wall of the chamber, with conductive rings mounted at the top and bottom of the carbon heating element for heating). The gap between the assembly and the inner wall of the pressure chamber is completely filled with pyrophyllite. The pyrophyllite and the assembly together constitute the assembled block. The assembly includes the Al-Ni alloy sample, boron nitride powder, elemental molybdenum, and zirconium dioxide. Figure 1 As shown, the details are as follows:

[0035] The Al-Ni alloy sample is placed in the heating chamber of a carbon heating element. Boron nitride powder fills the space between the Al-Ni alloy sample and the inner wall of the heating chamber. This boron nitride powder forms an insulating layer, preventing direct contact between the Al-Ni alloy sample and the carbon heating element, thus preventing contamination of the inner wall of the carbon heating element during the reaction process. The carbon heating element has a cylindrical structure, with a layer of elemental molybdenum covering both its upper and lower surfaces. Due to the excellent strength of elemental molybdenum, it can disperse the pressure applied to the upper and lower surfaces of the carbon heating element, thereby ensuring uniform pressure on the Al-Ni alloy sample. Zirconia material is circumferentially attached to the carbon heating element. Zirconia serves to insulate the Al-Ni alloy sample, slowing heat loss and ensuring complete high-pressure directional solidification of the Al-Ni alloy sample.

[0036] In this invention, the hydraulic press is a six-sided hydraulic press. Pyrophyllite needs to be dried at 200°C for 4 hours before use, and then stored at a constant temperature of 100°C for later use.

[0037] S3: The assembly is pressurized to 7 GPa using a hydraulic press. During this pressurization process, because the pyrophyllite completely fills the gap between the assembly and the inner wall of the pressure chamber, the lateral deformation is minimal when the hydraulic press applies pressure to the assembly from above and below. The pyrophyllite transmits the lateral pressure, ensuring uniform pressure on the assembly. Simultaneously, after energizing the conductive ring, the carbon heating element heats the Al-Ni alloy sample to 1500-1600℃ through the conductivity of elemental molybdenum. The temperature and pressure are maintained for 1 hour to allow the Al-Ni alloy sample to react completely, achieving the high-pressure solidification process of the Al-Ni alloy sample and obtaining the reactant.

[0038] S4: After cooling the reactant to room temperature with cooling water, remove the Al-Ni alloy sample from the heating chamber after depressurization to obtain the high-pressure solidified material.

[0039] Example 1

[0040] In this embodiment, high-pressure solidified materials under different pressures were prepared. In this embodiment, the raw materials were 99.99 wt.% Al and 99.99 wt.% Ni. The specific method for preparing the high-pressure solidified materials is as follows:

[0041] (1) Weigh 31.49g of Al block and 68.51g of Ni block, clean and dry them for later use.

[0042] (2) After the prepared Al and Ni blocks are placed into the electric arc furnace, the vacuum electric arc furnace is evacuated. Once the vacuum level is less than 2.0E1, the smelting can begin.

[0043] (3) The material in step (2) is ignited and melted. After the material is melted, the alloy is cooled and the melting is repeated 4 times to mix the alloy evenly.

[0044] (4) Turn off the electric arc melting power supply, wait for the alloy to cool to room temperature, and then remove the ingot under vacuum.

[0045] (5) Cut the ingot from step (4) into round bars of Φ3×3.7mm.

[0046] (6) The round bar obtained in step (5) was ground with 500-grit sandpaper to remove the cutting marks and then cleaned and dried to obtain an Al-Ni alloy sample. A boron nitride layer, a molybdenum sheet layer, a zirconium dioxide layer, and pyrophyllite were prepared. The pyrophyllite was then dried in a forced-air drying oven at 200°C for 4 hours and then stored at a constant temperature of 100°C for later use.

[0047] (7) Combine the dried sample and assembly materials obtained in step (6) according to... Figure 1 As shown in the diagram, the assembled structure is as follows:

[0048] The Al-Ni alloy sample was assembled into an assembly and placed in the pressure chamber of a hydraulic press. Pyrophyllite was filled between the assembly and the inner wall of the pressure chamber, and the pyrophyllite and the assembly together constituted an assembly block. The assembly included the Al-Ni alloy sample, boron nitride powder, a carbon heating element, elemental molybdenum, zirconium dioxide, and conductive rings. The Al-Ni alloy sample was placed in the heating chamber of the carbon heating element, with boron nitride powder filling the space between the sample and the inner wall of the heating chamber to prevent direct contact with the carbon heating element. Vertical and continuous narrow slits were formed in the sidewalls of the carbon heating element, and both its upper and lower surfaces were covered with a layer of elemental molybdenum to distribute pressure. Zirconium dioxide was circumferentially attached for insulation. Conductive rings were fitted to the top and bottom of the carbon heating element.

[0049] (8) The assembly obtained in step (7) was pressurized to 7 GPa using a six-sided hydraulic press. At the same time, the conductive ring was energized, and the carbon heating element heated the Al-Ni alloy sample to 1600℃ through the conductivity of elemental molybdenum. The sample was held at the same temperature and pressure for 1 hour to achieve the high-pressure solidification process of the Al-Ni alloy sample and obtain the reaction body.

[0050] (9) When the temperature of the reactant in step (8) is reduced to 25°C by cooling water, the pressure is released and the addition of cooling water is stopped. The Al-Ni alloy sample after reaction in the heating chamber is taken out to obtain the high-pressure solidified material.

[0051] Comparative Example 1

[0052] The difference from Example 1 is that in step (8), a six-sided hydraulic press is used to pressurize the assembly obtained in step (7) to 0.1 MPa.

[0053] Figure 2 The microstructures of NiAl alloys after solidification in Comparative Example 1 and Example 1 are shown. a) Microstructure of Comparative Example 1: After a eutectic reaction under normal pressure, the NiAl alloy yields Ni3Al and NiAl phases. The matrix phase is interwoven NiAl lath martensite, and the raised strip-shaped phases on the matrix are Ni3Al precipitates, dispersed throughout. b) Microstructure of Example 1: After high-pressure solidification, a full lamellar structure appears on the alloy surface, divided into large, medium, and small sizes, gradually increasing in size from the edge inwards.

[0054] Figure 3 yes Figure 2 TEM results for small and medium-sized sheets: a) is a bright-field image of a small sheet; b) is a bright-field image of different regions of the same size; c) is the surface scan result of Al element in b) and d) is the surface scan result of Ni element in b) According to the surface scan results, Al is more uniformly distributed and more biased towards the white phase region, while Ni has greater segregation and is more concentrated in the black phase region.

[0055] Figure 4 yes Figure 2TEM results for large and medium-sized lamellae: a) is a bright-field image containing large, medium, and small lamellae. The width of the large lamellae is approximately 1000 nm, the width of the medium lamellae is approximately 200 nm, and the width of the small lamellae is approximately 100 nm. b) is a SAED image of the large region. In the

[011] band axis direction, the angle between the twin and the basal plane of the matrix is ​​approximately 55°, which is the FCC phase. c) is a dark-field image of the large lamellae. d) is a dark-field image of the medium lamellae. e) is a high-resolution image of the boundary between the large and medium lamellae. It can be seen that twins and stacking faults exist in both types of lamellae. The diffraction patterns obtained from the lamellae and twins of both sizes are the Ni3Al phase of FCC. In the top large lamellae, TB represents the twin boundary. The corresponding twin boundary widening phenomenon can be seen. At the same time, there are defects such as dislocations and stacking faults. Figure f) is the FFT diagram obtained from the large-scale twinned region. The result is similar to that of Figure b), with two sets of diffraction patterns and extra fringes, indicating the presence of twins and stacking faults. Figure g) is a high-resolution image of a medium-sized sheet, with (200) and (1-11) crystal planes visible. The zone axis of this image is the

[011] direction of the L12 structure. Twins are present in the image, and the crystal structures on both sides are mirror-symmetrical. Figure h) is the FFT diagram of the twin, which can be confirmed as the Ni3Al phase of L12. The (100) crystal plane is present in one of the diffraction patterns, indicating the presence of a superlattice structure. Figure i) is the diffraction spot with the (100) crystal plane. The IFFT diagram obtained by inverse Fourier transform of the (200) crystal plane shows that there are a large number of dislocations in the twin. Stacking faults can be seen in the yellow box. Figure j) is an IFFT diagram obtained by performing an inverse Fourier transform on the (1 ̅1 ̅1) plane of another set of diffraction spots in the twin, confirming that the twin is mirror-symmetric.

[0056] Figure 5 The mechanical property data obtained from nanoindentation experiments on samples obtained under normal pressure in Example 1 and high pressure in Example 1 are shown. a) is the nanoindentation load-depth curve. Under the same loading load, the deeper the nanoindentation, the lower the hardness. The depth of the sample under normal pressure is around 500 nm, and the depth of the sample under high pressure is around 300 nm. The hardness obtained from this experiment is 3.103 GPa for the sample under normal pressure and 7.288 GPa for the sample under high pressure. b) is the stress-strain constitutive relationship characterization diagram. It can be seen that the curve of the high pressure sample is above the curve under normal pressure. The table in the figure shows that the elastic modulus E increased from 123.02 GPa under normal pressure to 177.3 GPa under 7 GPa, an increase of 44.12%; the yield strength σy increased from 346.7 MPa to 1151.5 MPa, an overall increase of 2.3 times, indicating that the mechanical properties of the high pressure sample are better.

[0057] Comparative Example 2

[0058] The difference from Example 1 is that in step (1), 95.14g of Ni block and 4.86g of Al block are weighed to pre-obtain Ni-Al. 10 The alloy is prepared by weighing out 92.5g of Ni and 7.5g of Al blocks to obtain a Ni-Al alloy. 15 The alloy was then prepared by weighing out 76.54g of Ni and 23.46g of Al, to obtain a Ni-Al alloy. 40 alloy.

[0059] Figure 6 Is Ni-Al 10 Alloy, Ni-Al 15 Alloys and Ni-Al 40 Comparison of metallographic images of the alloys obtained by the preparation methods in Example 1 and Comparative Example 1. a) Ni-Al alloy obtained by the method in Comparative Example 1. 10 a) Metallographic photographs of the alloy sample, showing irregularly shaped blocky phases between the grains; b) Ni-Al obtained by the method in Comparative Example 1. 15 The metallographic photograph of the alloy sample shows obvious grain boundaries and no lamellar structure was observed; c) is the Ni-Al obtained by the method in Example 1. 40 The metallographic photograph of the alloy shows large grain boundary sizes, indicating a single-phase solid solution. After high-pressure treatment at 7 GPa, d) is the Ni-Al obtained by the method in Example 1. 10 The alloy exhibits reduced intergranular precipitates and no obvious lamellar structure; e) is the Ni-Al obtained by the method in Example 1. 15 The alloy has a second phase precipitated; f) is the Ni-Al obtained by the method in Example 1. 40 The alloy produces many precipitates, but still lacks a distinct lamellar structure.

[0060] The comparison between Example 1 and Comparative Example 2 illustrates that the ratio of Ni to Al in the Ni-Al alloy also affects the formation of the microstructure. Under the ratio in Example 1, a full lamellar structure of high-density twins and stacking faults was obtained. However, under several ratios in Comparative Example 2, the same microstructure as in Example 1 was not obtained. In this example, the Ni-Al alloy obtained by using a specific combination of Ni and Al as raw materials can only obtain a full lamellar structure of high-density twins and stacking faults under specific conditions. This result was unexpected.

[0061] Comparative Example 3

[0062] The difference from Example 1 is that in step (1), 23.53g of Co block, 20.76g of Cr block, 23.43g of Ni block, 22.3g of Fe block, 0.96g of Al block, and 9.02g of Cu block are weighed as alloy raw materials to obtain FeCoCrNiAlCu high-entropy alloy.

[0063] Figure 7 These are scanning electron microscope images of FeCoCrNiAlCu HEAs. a) is a micrograph of the high-entropy alloy obtained according to the method of Comparative Example 1, and b) is a micrograph of the high-entropy alloy obtained according to the method of Example 1. It can be seen that after high pressure treatment, the alloy gradually transforms into equiaxed dendrites, and the white phase becomes finer and more fragmented as the pressure increases, but the full lamellar structure still does not appear.

[0064] The comparison between Example 1 and Comparative Example 3 illustrates that not all materials, when prepared using the method described in this invention, can achieve a fully lamellar alloy structure with high-density twins and stacking faults. In this example, the Ni-Al alloy obtained using Ni and Al as raw materials can achieve a fully lamellar alloy structure with high-density twins and stacking faults under specific conditions, which is something that cannot be predicted in advance.

Claims

1. A method for constructing a fully lamellar structure of a NiAl alloy, characterized in that, Includes the following steps: (1) Preparation of NiAl-based alloy ingots; (2) The NiAl-based alloy ingot is combined with a boron nitride layer, a molybdenum sheet layer and a zirconium dioxide layer to form a high-pressure assembly. The boron nitride layer surrounds the periphery of the NiAl-based alloy ingot, the molybdenum sheet layer is placed above and below the boron nitride layer, and the zirconium dioxide layer covers the outer periphery of the boron nitride layer and the molybdenum sheet layer. (3) The high-pressure assembly is placed in the heating chamber and subjected to high-pressure solidification treatment using a press to obtain a NiAl alloy full lamellar structure; the pressure of the high-pressure solidification treatment is 6-8 GPa, the temperature of the high-pressure solidification treatment is 1500-1650℃, and the NiAl alloy full lamellar structure is a NiAl alloy full lamellar structure containing high-density twins and stacking faults.

2. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, Before the high-pressure solidification process, pyrophyllite is filled into the gap between the high-pressure assembly and the heating chamber.

3. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, Before performing step (2), the NiAl-based alloy ingot is polished on 500-600 grit sandpaper.

4. The method for producing a fully lamellar structure of a NiAl alloy according to claim 2, characterized in that, Before use, pyrophyllite should be dried at 200-220℃ for 3-4 hours, and then stored at a constant temperature of 100-105℃ for later use.

5. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, The purity of the Al and Ni blocks used to prepare the NiAl-based alloy ingot is at least 99.99%.

6. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, The atomic percentage content of Ni in the NiAl-based alloy is 65-75 at.

7. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, The pressure of the high-pressure solidification process is 7 GPa.

8. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, The high-pressure solidification treatment is performed at a temperature of 1600℃.

9. The method for producing a fully lamellar structure of a NiAl alloy according to claim 1, characterized in that, The heat preservation and pressure holding time for the high-pressure solidification treatment is 0.5-2 h.

10. A NiAl alloy full-lamellar microstructure material containing high-density twins and stacking faults prepared by the method according to any one of claims 1-9.

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