High-performance heterogeneous nickel-based alloy based on multi-strain path rolling and preparation method of high-performance heterogeneous nickel-based alloy

Abstract

The invention discloses a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling and a preparation method of the high-performance heterogeneous nickel-based alloy. Belongs to the technical field of high-performance metal structure materials and preparation thereof. The alloy is a nickel-based medium-entropy alloy containing a gamma'strengthening phase. The core of the preparation method is as follows: after solution treatment, a multi-strain path rolling process is innovatively adopted, and according to the process, a complex and non-uniform strain field and defect configuration are actively introduced into the alloy by changing the rolling direction. And finally, through two-stage aging treatment, the prefabricated defect structure is converted into an ideal multi-scale heterogeneous structure. Due to the heterogeneous structure, when the alloy is stretched at the high temperature of 800 DEG C, the yield strength reaches about 1060 MPa, the tensile strength reaches about 1104 MPa, meanwhile, the elongation at break is kept at about 21.2%, and excellent combination of high strength and good plasticity is achieved. The method is simple and controllable in process, and a new way is provided for obtaining high-performance high-temperature structural materials.

Description

Technical Field

[0001] This invention relates to a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling and its preparation method. Specifically, it relates to a nickel-based alloy suitable for high-temperature extreme environments (such as hot-end components of aero-engines and gas turbines). More specifically, it relates to a method for actively constructing a heterogeneous microstructure with high thermal stability in a nickel-based medium-entropy alloy through an innovative "multi-strain path rolling" process, and the alloy material obtained by this method that exhibits both ultra-high strength and good plasticity at high temperatures. This belongs to the field of high-performance metallic structural materials and their preparation technology. Background Technology

[0002] Nickel-based superalloys are irreplaceable materials for manufacturing critical hot-end components such as turbine disks and blades in aero-engines due to their excellent high-temperature strength, creep resistance, and oxidation resistance. Their high-temperature strength primarily derives from precipitation strengthening by the γ′ phase. Traditional techniques mainly focus on controlling the volume fraction, size, and distribution of the γ′ phase through alloying design and optimized heat treatment processes to improve performance. However, as the service temperatures of components continue to approach material limits, traditional strengthening methods are facing performance improvement bottlenecks.

[0003] In recent years, the concept of heterostructured materials has provided a new approach to breaking the inverse relationship between material strength and plasticity. This concept involves constructing regions with significantly different properties (such as recrystallized fine-grained regions and hard regions such as deformable microstructures) within the material. It utilizes the strain gradient during deformation to generate geometrically necessary dislocations, inducing strong back stress and heterostructure-induced strengthening, thereby significantly improving strength while maintaining considerable plasticity. Currently, such structures are often prepared by introducing large plastic deformations (such as intense rolling and high-pressure torsion). However, existing technologies in this area primarily focus on achieving and controlling the "deformation amount," essentially reducing the process to rolling under a single or fixed strain path. This method makes it difficult to effectively and optimally control the distribution, proportion, and morphology of soft and hard regions. Therefore, developing a novel preparation method that goes beyond simple "deformation amount" control and starts from the more fundamental "strain path" design to actively "pre-fabricate" specific defect configurations conducive to forming high-performance, highly stable heterostructures has become a technical challenge to be solved in this field. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an innovative method for preparing nickel-based alloys and the resulting high-performance alloys. The core of this method is to start with the design of the "strain path," using multi-strain path rolling to achieve the active design and pretreatment of the internal defect configuration of the material, ultimately obtaining an alloy with a three-dimensional heterogeneous structure, high heterogeneous interface density, and excellent high-temperature strength and plasticity synergistically.

[0005] Meanwhile, this invention provides an application of high-performance heterogeneous nickel-based alloys based on multi-strain path rolling in high-temperature extreme environments, including aero-engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A method for preparing high-performance heterogeneous nickel-based alloys based on multi-strain path rolling includes the following steps performed sequentially: (1) Solution treatment: The nickel-based medium-entropy alloy with a specific composition is solution treated at a temperature of 1050 °C to 1120 °C, held at that temperature for 2 to 6 h and then rapidly cooled. This step aims to obtain a solid solution with uniform composition, providing a uniform matrix for subsequent deformation energy storage.

[0007] (2) Multi-step strain path rolling: The solution-treated alloy is rolled at room temperature, with the total deformation controlled between 70% and 85%. This rolling is not a simple unidirectional or vertical reversal rolling process, but a multi-step rolling process comprising at least three rolling stages with a specific asymmetric strain path relationship, which sequentially includes: First direction rolling: Rolling is performed along the first direction (initial rolling direction, RD) of the alloy sample, with a cumulative deformation of 20% to 40%.

[0008] Second-direction rolling: The sample after the above rolling is rotated around its normal direction by an intermediate angle other than 90°. , where 30°≤ The angle is ≤60°, and rolling is then performed along this new direction, increasing the cumulative deformation by 20% to 30%. This step introduces non-orthogonal shear strain components, breaking the deformation symmetry.

[0009] Third direction rolling: The specimen is rotated again around its normal direction so that the cumulative rotation angle of the specimen relative to the initial first direction is 90°, and then rolled along this final direction until the total deformation reaches 70% to 85%.

[0010] Asymmetric strain path rolling introduces complex, multidimensional, spatially specific strain fields and dislocation structures into the material, thereby creating defects conducive to the formation of highly thermally stable three-dimensional heterogeneous structures. Preferably, the intermediate angle... It is 45°.

[0011] (3) Two-stage aging treatment: The alloy after multi-strain path rolling is subjected to a two-step aging treatment. The first step is to hold at a relatively high temperature (1000 ℃-1050 ℃) for 1-3 h, mainly to promote incomplete recrystallization on the pre-formed defect structure and form fine equiaxed recrystallized grains. The second step is to hold at a relatively low temperature (750 ℃-850 ℃) for 2-8 h, mainly to further control the size and distribution of the γ′ precipitate in the recrystallization zone and the non-recrystallized deformation zone.

[0012] Through the synergistic process of "solid solution + rolling with specific asymmetric multi-step strain path + two-stage aging", an ideal microstructure is finally obtained in the alloy.

[0013] A high-performance heterogeneous nickel-based alloy prepared by the above method is characterized by its microstructure comprising three elements: (1) Deformational structures with high dislocation density (“hard regions”), (2) Recrystallized equiaxed fine-grained regions (“soft regions”) with an average grain size of 500 nm to 1000 nm. (3) Dispersed nanoscale γ′ precipitates.

[0014] The deformed and recrystallized fine-grained regions are not simply alternating layers, but rather intertwined and interwoven in three-dimensional space, forming a three-dimensional heterogeneous structure. This structure possesses an extremely high heterogeneous interface density, not less than 5.0 × 10⁻⁶. -2 μm -1 .

[0015] The chemical composition of the nickel-based medium-entropy alloy, by atomic percentage (at.%), is as follows: Ni as the matrix, Co: 20.0-25.0%, Cr: 13.0-18.0%, Al: 4.0-6.0%, Ti: 4.0-6.0%, Mo: 1.0-3.0%, W: 0.1-1.0%, Fe: 0.1-1.0%, Zr: 0.01-0.1%. This composition system ensures that the alloy has the ability to form the γ′ phase and good high-temperature performance potential.

[0016] The present invention provides a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling. In a high-temperature tensile test at 800 ℃, the alloy has a yield strength of 1013-1116 MPa, a tensile strength of 1051-1151 MPa, and a fracture elongation of 19.7-23.5%.

[0017] This invention relates to the application of a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling in high-temperature extreme environments. These environments include aero-engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft.

[0018] Compared with the prior art, the present invention has the following significant advantages: (1) Achieving an excellent balance between strength and plasticity at high temperatures: The multi-scale heterogeneous structure constructed through a specific process synergistically exerts the effects of heterogeneous strengthening and precipitation strengthening. In a high-temperature tensile test at 800 ℃, the yield strength of the alloy of this invention reaches approximately 1060 MPa, the tensile strength reaches approximately 1104 MPa, and the elongation at break remains at approximately 21.2%. This combination of properties is significantly superior to the performance of alloys of the same composition treated by traditional processes or most commercial high-temperature alloys at the same temperature.

[0019] (2) Simple and controllable process with good repeatability: The preparation method of this invention (solution at 1050 ℃ / 4 h + 80% multi-strain path rolling + two-step aging at 1000 ℃ / 2 h + 800 ℃ / 4 h) has clear parameters and steps. Room temperature multi-strain path rolling is the key step, avoiding the high-temperature heating equipment and energy consumption required for hot rolling, and also reducing high-temperature oxidation. The entire process route does not require complex deformation heat treatment cycles or extreme deformation conditions, and is easy to implement on conventional metallurgical processing lines, which is conducive to stable industrial production.

[0020] (3) Activating material potential through process innovation: Without changing the basic alloy composition, this invention achieves a leapfrog improvement in performance by innovatively designing the process for a mature nickel-based medium-entropy alloy system. This proves that "process control of microstructure" is an efficient way to develop a new generation of high-performance materials, and provides a new idea for tapping the performance potential of existing alloy systems.

[0021] (4) High structural stability and broad application prospects: The constructed heterogeneous structure has good stability at high temperatures, and the fine-grained region and nano-γ′ phase are not prone to excessive growth. This enables the alloy to maintain excellent comprehensive performance at temperatures of 800 ℃ or even higher, and it has great application potential in high-end equipment fields such as aero-engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft.

[0022] This invention discloses a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling and its preparation method, belonging to the field of metallic structural materials technology. The alloy is a nickel-based medium-entropy alloy containing a γ′ strengthening phase. The core of the preparation method lies in the innovative use of a multi-strain path rolling process after solution treatment. This process actively introduces complex, non-uniform strain fields and defect configurations into the alloy by changing the rolling direction. Finally, a two-stage aging treatment transforms the pre-introduced defect structure into an ideal multi-scale heterogeneous microstructure. This heterogeneous structure enables the alloy to achieve a yield strength of approximately 1060 MPa and a tensile strength of approximately 1104 MPa at 800 ℃, while maintaining a fracture elongation of approximately 21.2%, achieving an excellent combination of high strength and good plasticity. This invention offers a simple and controllable process, providing a new approach for obtaining high-performance high-temperature structural materials. Attached Figure Description

[0023] Figure 1 The image shows an electron backscattering diffraction pattern of the heterostructure in the nickel-based alloy after multi-strain path rolling with 80% deformation and double-stage aging treatment in the example. Figure 2 The image shown is a transmission electron microscope image of the heterogeneous structure in the nickel-based alloy after multi-strain path rolling with 80% deformation and double-stage aging treatment in the example. Figure 3 The image shown is a scanning electron microscope image of the precipitated phases in the nickel-based alloy after multi-strain path rolling with 80% deformation and double-stage aging treatment in the example. Figure 4 This is a comparison graph of the high-temperature mechanical properties of the examples and the solid solution nickel-based alloys at 800 °C; Figure 5 This is a schematic diagram illustrating the principle of solution treatment, 80% deformation multi-strain path rolling, and two-stage aging treatment described in this invention. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention. Example 1

[0025] This embodiment demonstrates a method for preparing high-performance heterogeneous nickel-based alloys using the "multi-step asymmetric strain path rolling" process described in this invention. The selected alloy is a nickel-based medium-entropy alloy with the following chemical composition in atomic percentages (at.%): Ni as the matrix, Co: 22.94%, Cr: 15.46%, Al: 5.10%, Ti: 4.96%, Mo: 1.80%, W: 0.34%, Fe: 0.50%, Zr: 0.02%.

[0026] like Figure 5 As shown, the first step in the preparation process is solution treatment. Block samples with dimensions of 7 mm (thickness) × 10 mm (width) × 50 mm (length) are cut from alloy bars of the aforementioned alloy composition and placed in a box furnace. The samples are solution treated at 1050 °C in air, held for 4 h, and then cooled to room temperature in air. This step aims to obtain a homogeneous solid solution, laying the foundation for subsequent deformation treatment.

[0027] Subsequently, multi-strain path rolling was performed. The surface of the solution-cooled sample was polished to remove oxide scale, and then rolled at room temperature on a two-roll cold rolling mill, with the total deformation strictly controlled at 80%. The rolling path used in this embodiment was as follows: first, rolling was performed along the length direction of the sample (first direction, RD) with a single-pass reduction of approximately 0.20 mm, accumulating a deformation of 30%; then, the sample was rotated 45° around its normal direction (ND) and rolled along this new direction (second direction), increasing the cumulative deformation to 55%; finally, the sample was rotated again around its normal direction by 45°, bringing the cumulative rotation angle to 90°, and rolled along this final direction (third direction) with a single-pass reduction of approximately 0.10 mm for finishing rolling to precisely control the flatness and microstructure uniformity of the sheet, until the total deformation reached 80%, yielding a sheet with a thickness of approximately 1.0 mm.

[0028] Finally, the rolled sheet undergoes a two-stage aging treatment. The sheet is placed in a heat treatment furnace and first held at 1000℃ for 2 hours, then air-cooled to room temperature. This step aims to promote recrystallization of some deformed structures. Next, it is held at 800℃ for 4 hours, then air-cooled to room temperature. The core purpose of this step is to further control the size and distribution of the γ′ precipitate in the recrystallized and non-recrystallized deformed zones, thereby achieving the final strengthening of the material.

[0029] Microstructural characterization of the obtained alloy sample revealed the source of its superior performance. Observations using electron backscatter diffraction techniques showed that ( Figure 1Where RX represents the recrystallized region and NRX represents the non-recrystallized region (i.e., the residual deformation structure region), a heterogeneous structure consisting of an alternating distribution of residual deformation structure regions and recrystallized equiaxed fine-grained regions was successfully constructed within the alloy. The volume fraction of the recrystallized region is approximately 64.75%, with an average grain size of approximately 672.9 nm, and the calculated heterostructure density is as high as approximately 6.6 × 10⁻⁶. -2 μm -1 Transmission electron microscopy observation ( Figure 2 This further confirms the coexistence of recrystallized regions and residual deformed structures with high dislocation density. Scanning electron microscopy observation (…) Figure 3 The study revealed that γ′ precipitates were dispersed in the recrystallized and residual deformation regions. This unique heterogeneous structure endows the alloy with excellent high-temperature mechanical properties, such as... Figure 4 As shown, in the high-temperature tensile test at 800 ℃, its yield strength reached 1060 MPa, its tensile strength reached 1104 MPa, and its elongation at break remained at 21.2%, achieving an excellent combination of high strength and good plasticity.

[0030] This embodiment demonstrates the application of a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling in high-temperature extreme environments. These high-temperature extreme environments include aero-engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft.

[0031] Comparative Example 1

[0032] The same alloy, solution treatment, and aging process as in Example 1 were used. The only difference was the rolling path: first, rolling was performed along the RD direction until the cumulative deformation reached 50%; then, the sample was rotated 90° and rolled along the perpendicular direction until the total deformation reached 80%. This process is a traditional two-stage orthogonal rolling. After the same aging treatment, the properties of this sample at 800 °C were: yield strength 880 MPa, tensile strength 930 MPa, and elongation at break 14.5%. Its properties were significantly lower than those of the Example 1. Microstructural analysis showed that although it formed a heterogeneous structure, the soft and hard phases were distributed in a more obvious layered manner, with strong anisotropy. The heterogeneous deformation-induced strengthening effect was weaker than that of the three-dimensional heterogeneous structure in Example 1.

[0033] Comparative Example 2

[0034] The same alloy, solution treatment, and aging process as Example 1 were used. The only difference was the rolling path: first, rolling along the RD direction with a cumulative deformation of 30%; then rotating 90° and rolling to increase the cumulative deformation to 55%; finally rotating 45° and rolling to a total deformation of 80%. The properties of this sample at 800 °C were: yield strength 820 MPa, tensile strength 875 MPa, and elongation at break 11.8%. These properties were significantly lower than those of Comparative Example 1 and Example 1. This indicates that not following the optimized path of the present invention, which is "first asymmetric intermediate angle, then rotation to a cumulative 90°", but instead using a chaotic sequence of "first orthogonal, then deflection", leads to strain path conflicts, making it impossible to form a coordinated soft and hard phase distribution, which is not conducive to obtaining the optimal strength-ductility combination.

[0035] Comparative Example 3

[0036] The same alloy, solution treatment, and aging process as in Example 1 were used. The only difference was the rolling path: first, rolling along the RD direction, accumulating 30% deformation; then rotating 20° and rolling, increasing the cumulative deformation to 55%; finally rotating 70° and rolling to a total deformation of 80%. The properties of this sample at 800 °C were: yield strength 790 MPa, tensile strength 840 MPa, and elongation at break 9.2%. Its strength and plasticity were the worst among all the comparative schemes. The microstructure showed that due to the small intermediate rotation angle (20°), the deformation was close to a single direction, resulting in insufficient strain asymmetry, inadequate subsequent recrystallization, an excessively high proportion of deformed microstructure, and poor coordination of deformation between soft and hard regions.

[0037] Comparative Example 4

[0038] The same alloy, solution treatment, and aging process as Example 1 were used. The only difference was the rolling path: first, rolling along the RD direction, accumulating 30% deformation; then rotating 70° and rolling, increasing the cumulative deformation to 55%; finally rotating 20° and rolling to a total deformation of 80%. The properties of this sample at 800 °C were: yield strength 805 MPa, tensile strength 855 MPa, and elongation at break 10.5%. The performance was significantly lower than Example 1, but slightly better than Comparative Example 3. Its microstructure was less uniform, with obvious weak areas. This indicates that when the intermediate rotation angle (70°) is too large, close to but not 90°, the introduced strain path is also not optimal, and it cannot construct the most uniform and stable three-dimensional defect network in the material as in Example 1 (θ = 45°).

[0039] The results show that Example 1 of this invention successfully constructed a heterogeneous microstructure composed of a residual deformation zone, a recrystallization zone, and a nano-γ′ phase in a nickel-based medium-entropy alloy of a specific composition through a synergistic process of "solution treatment at 1050 °C for 4 h + rolling with a specific asymmetric multi-step strain path + two-stage aging at 1000 °C for 2 h + 800 °C for 4 h". This structure, through the synergistic effect of heterogeneous deformation-induced strengthening and precipitation strengthening, enables the alloy to simultaneously achieve a high yield strength of 1060 MPa and a good elongation of 21.2% at a high temperature of 800 °C, with comprehensive performance significantly superior to traditional homogeneous alloys (solution state). This invention provides a method with clear process parameters, a simple process, and easy industrialization, offering an effective technical solution for developing a new generation of high-performance nickel-based high-temperature structural materials. Example 2

[0040] This embodiment demonstrates a method for preparing high-performance heterogeneous nickel-based alloys using the "multi-step asymmetric strain path rolling" process described in this invention. The selected alloy is a nickel-based medium-entropy alloy with the following chemical composition in atomic percentages (at.%): Ni as the matrix, Co: 20.0%, Cr: 13.0%, Al: 4.0%, Ti: 4.0%, Mo: 1.0%, W: 0.1%, Fe: 0.1%, Zr: 0.01%.

[0041] In the preparation process, solution treatment is performed first. Block samples with dimensions of 7 mm (thickness) × 10 mm (width) × 50 mm (length) are cut from alloy bars of the aforementioned alloy composition and placed in a box furnace. The samples are solution treated at 1120 °C in air, held at that temperature for 2 h, and then removed and cooled to room temperature in air. This step aims to obtain a homogeneous solid solution, laying the foundation for subsequent deformation treatment.

[0042] Subsequently, multi-strain path rolling was performed. The surface of the sample after solution cooling and air grinding was polished to remove oxide scale, and then rolled at room temperature on a two-roll cold rolling mill, with the total deformation strictly controlled at 70%. The rolling path used in this embodiment is as follows: first, rolling is performed along the length direction of the sample (first direction, RD) with a single-pass reduction of about 0.20 mm, and the cumulative deformation reaches 20%; then, the sample is rotated 30° around its normal (ND) and rolled along this new direction (second direction), increasing the cumulative deformation to 40%; finally, the sample is rotated again around its normal by 60°, so that the cumulative rotation angle reaches 90°, and rolled along this final direction (third direction) with a single-pass reduction of about 0.10 mm for finishing rolling to precisely control the flatness and microstructure uniformity of the plate, until the total deformation reaches 70%, and a plate with a thickness of about 1.14 mm is obtained.

[0043] Finally, the rolled sheet undergoes a two-stage aging treatment. The sheet is placed in a heat treatment furnace and first held at 1050℃ for 1 hour, then air-cooled to room temperature. This step aims to promote recrystallization of some deformed structures. Next, it is held at 750℃ for another 8 hours, then air-cooled to room temperature. The core purpose of this step is to further control the size and distribution of the γ′ precipitate in the recrystallized and non-recrystallized deformed zones, thereby achieving the final strengthening of the material.

[0044] The high-performance heterogeneous nickel-based alloy obtained in this embodiment based on multi-strain path rolling has a yield strength of 1013 MPa and a tensile strength of 1051 MPa in a high-temperature tensile test at 800 ℃, while maintaining a fracture elongation of 19.7%, achieving an excellent combination of high strength and good plasticity.

[0045] This embodiment demonstrates the application of a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling in high-temperature extreme environments. These high-temperature extreme environments include aero-engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft. Example 3

[0046] This embodiment demonstrates a method for preparing high-performance heterogeneous nickel-based alloys using the "multi-step asymmetric strain path rolling" process described in this invention. The selected alloy is a nickel-based medium-entropy alloy with the following chemical composition in atomic percentages (at.%): Ni as the matrix, Co: 25.0%, Cr: 18.0%, Al: 6.0%, Ti: 6.0%, Mo: 3.0%, W: 1.0%, Fe: 1.0%, Zr: 0.1%.

[0047] In the preparation process, solution treatment is performed first. Block samples with dimensions of 7 mm (thickness) × 10 mm (width) × 50 mm (length) are cut from alloy bars of the aforementioned alloy composition and placed in a box furnace. The samples are solution treated at 1100 °C in air, held at that temperature for 6 h, and then removed and cooled to room temperature in air. This step aims to obtain a homogeneous solid solution, laying the foundation for subsequent deformation treatment.

[0048] Subsequently, multi-strain path rolling was performed. The surface of the solution-cooled sample was polished to remove oxide scale, and then rolled at room temperature on a two-roll cold rolling mill, with the total deformation strictly controlled at 85%. The rolling path used in this embodiment was as follows: first, rolling was performed along the length direction of the sample (first direction, RD) with a single-pass reduction of approximately 0.20 mm, resulting in a cumulative deformation of 40%; then, the sample was rotated 60° around its normal direction (ND) and rolled along this new direction (second direction), increasing the cumulative deformation to 70%; finally, the sample was rotated again around its normal direction by 30°, bringing the cumulative rotation angle to 90°, and rolled along this final direction (third direction) with a single-pass reduction of approximately 0.10 mm for finishing rolling to precisely control the flatness and microstructure uniformity of the sheet, until the total deformation reached 85%, yielding a sheet with a thickness of approximately 0.94 mm.

[0049] Finally, the rolled sheet undergoes a two-stage aging treatment. The sheet is placed in a heat treatment furnace and first held at 1025℃ for 3 hours, then air-cooled to room temperature. This step aims to promote recrystallization of some deformed structures. Next, it is held at 850℃ for 2 hours, then air-cooled to room temperature. The core purpose of this step is to further control the size and distribution of the γ′ precipitate in the recrystallized and non-recrystallized deformed zones, thereby achieving the final strengthening of the material.

[0050] The high-performance heterogeneous nickel-based alloy obtained in this embodiment based on multi-strain path rolling has a yield strength of 1116 MPa and a tensile strength of 1151 MPa in a high-temperature tensile test at 800 ℃, while maintaining a fracture elongation of 23.5%, achieving an excellent combination of high strength and good plasticity.

[0051] This embodiment demonstrates the application of a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling in high-temperature extreme environments. These high-temperature extreme environments include aero-engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft.

[0052] It should be understood that, in order to simplify this disclosure and aid in understanding one or more of the various aspects of the invention, features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof in the above description of exemplary embodiments of the invention. However, this method of disclosure should not be interpreted as reflecting an intention that the claimed invention requires more features than expressly recited in each claim. Rather, as reflected in the claims, inventive aspects lie in fewer than all the features of the foregoingly disclosed embodiments. Therefore, the claims, following the detailed description, are hereby expressly incorporated into that detailed description, wherein each claim itself is a separate embodiment of the invention.

[0053] Although the invention has been described with reference to a limited number of embodiments, those skilled in the art will understand from the foregoing description that other embodiments are conceivable within the scope of the invention described herein. Furthermore, it should be noted that the language used in this specification has been chosen primarily for readability and instructional purposes, and not for the purpose of interpreting or limiting the subject matter of the invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the invention is illustrative and not restrictive, and the scope of the invention is defined by the appended claims.

[0054] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing high-performance heterogeneous nickel-based alloys based on multi-strain path rolling, characterized in that, Includes the following steps: Step 1, solution treatment: The nickel-based medium-entropy alloy is solution treated at a temperature of 1050-1120 ℃, held at that temperature for 2-6 hours, and then cooled. Step 2, multi-step strain path rolling: The solution-treated alloy is rolled at room temperature, with the total deformation controlled at 70-85%; First direction rolling: Rolling is performed along the first direction of the alloy sample, with a cumulative deformation of 20-40%; Second direction rolling: The sample after the above rolling is rotated around its normal direction by an intermediate angle. , where 30°≤ ≤60°, then rolling is carried out along this new direction, increasing the cumulative deformation by 20-30%; Third-direction rolling: The sample is rotated again around its normal direction, so that the cumulative rotation angle of the sample relative to the initial first direction is 90°, and then rolled along this final direction until the total deformation reaches 70-85%; Step 3, two-stage aging treatment: The alloy after multi-step strain path rolling is subjected to two-stage aging treatment; The first step is to keep the temperature at 1000-1050 ℃ for 1-3 hours; The second step is to keep the temperature at 750-850 ℃ for 2-8 hours.

2. The preparation method according to claim 1, characterized in that, In step one, the nickel-based medium-entropy alloy has the following chemical composition by atomic percentage: Ni as the matrix, Co: 20.0-25.0%, Cr: 13.0-18.0%, Al: 4.0-6.0%, Ti: 4.0-6.0%, Mo: 1.0-3.0%, W: 0.1-1.0%, Fe: 0.1-1.0%, Zr: 0.01-0.1%.

3. The preparation method according to claim 1, characterized in that, In step two, the first direction is the length direction of the sample.

4. The preparation method according to claim 1, characterized in that, In step two, the single-pass reduction in the first direction rolling is 0.20 mm.

5. The preparation method according to claim 1, characterized in that, In step two, the single-pass reduction in the third-direction rolling is 0.10 mm.

6. The preparation method according to claim 1, characterized in that, In step two, the middle angle It is 45°.

7. A high-performance heterogeneous nickel-based alloy based on multi-strain path rolling obtained by the preparation method according to any one of claims 1-6.

8. A high-performance heterogeneous nickel-based alloy based on multi-strain path rolling according to claim 7, characterized in that, In the high-temperature tensile test at 800 ℃, the alloy's yield strength reached 1013-1116 MPa, its tensile strength reached 1051-1151 MPa, and its elongation at break remained at 19.7-23.5%.

9. The application of a high-performance heterogeneous nickel-based alloy based on multi-strain path rolling as described in claim 7 in high-temperature extreme environments.

10. The application according to claim 9, characterized in that, High-temperature extreme environments include aircraft engine turbine disks, gas turbine blades, and high-temperature structural components of spacecraft.

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