A nickel-based alloy, its preparation method and application

Abstract

This invention relates to the field of nickel alloy materials technology, specifically to a nickel-based alloy, its preparation method, and its applications. The invention relates to a nickel-based alloy, comprising, by mass percentage: Al 4.0%–5.5%, Cr 9.0%–12.0%, Fe 3.5%–6.0%, V 3.5%–4.5%, with the balance being Ni. This invention ensures that the elements Al, Cr, Fe, V, and Ni in the nickel-based alloy meet the above-mentioned proportions, and that the mass percentage of each element satisfies Md = M / (m1+m2+m3+m4+m5) < 0.94. This guarantees that the alloy does not produce harmful phases under long-term exposure to high temperatures, exhibits good structural stability, suitable γ' volume fraction and γ' dissolution temperature, a wide hot working window, and good overall mechanical properties.

Description

Technical Field

[0001] This invention relates to the field of nickel alloy materials technology, and more specifically, to a nickel-based alloy, its preparation method, and its application. Background Technology

[0002] Nickel alloys possess excellent high-temperature strength, good resistance to oxidation and hot corrosion, good fatigue performance, and fracture toughness. High-temperature materials require a significant ability to maintain their properties at high temperatures, a key characteristic being their ability to withstand loads at operating temperatures close to their melting point. If the operating temperature is expressed as T... oper and melting point T m Then, the corresponding temperature is defined as τ = T. oper / T m Practical applications have shown that τ is greater than approximately 0.6. Based on this theory, in the search for this high-temperature material, it was discovered that the τ corresponding to nickel (melting point 1455℃) operating at 1000℃ is (1000+273) / (1455+273)~0.75. Therefore, nickel was chosen as a material for high-temperature applications.

[0003] Nickel alloys exhibit precipitation strengthening with γ'-Ni3Al as the second phase. Improving the properties of the γ'-Ni3Al phase is beneficial for enhancing the performance of nickel alloys. The excellent mechanical properties of nickel alloys are crucial for the stable operation of aero-engines and are a key factor in promoting the development of the aviation industry. Therefore, the superior mechanical properties of nickel-based superalloys are of great significance to the development of my country's aerospace industry. Developing new nickel alloy strengthening systems will contribute to the production and development of my country's aviation and aerospace industries.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] One object of the present invention is to provide a nickel-based alloy that does not produce harmful phases under long-term exposure to high-temperature conditions, has good structural stability, suitable γ' volume fraction and γ' dissolution temperature, has a wide hot working window, and good comprehensive mechanical properties.

[0006] Another object of the present invention is to provide a method for preparing the nickel-based alloy described above, which is simple and easy to implement, and the resulting nickel-based alloy has excellent mechanical properties.

[0007] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0008] A nickel-based alloy, comprising, by weight percentage: Al 4.0%–5.5%, Cr 9.0%–12.0%, Fe 3.5%–6.0%, V 3.5%–4.5%, with the balance being Ni;

[0009] Let the mass percentage of Al be a, the mass percentage of Cr be b, the mass percentage of Fe be c, the mass percentage of V be d, and the mass percentage of Ni be e; m1 = a / 26.98; m2 = b / 52.00; m3 = c / 55.85; m4 = d / 50.94; m5 = e / 58.69;

[0010] M=1.900m1+1.142m2+0.858m3+1.543m4+0.717m5;

[0011] Md = M / (m1+m2+m3+m4+m5), and Md < 0.94.

[0012] In some embodiments, the total mass percentage of Cr, Fe, and V satisfies: 18% ≤ b + c + d ≤ 22.5%.

[0013] In some embodiments, the ratio of the total mass percentage of Al and Cr to the total mass percentage of Fe and V satisfies: 1.35 ≤ (a+b) / (c+d) ≤ 2.44.

[0014] In some embodiments, the content of harmful phases in the nickel-based alloy is 0 at 650°C.

[0015] In some embodiments, the volume fraction of the γ' phase in the nickel-based alloy at 750°C is 40% to 55%.

[0016] In some embodiments, the γ' dissolution temperature of the nickel-based alloy is below 1100°C.

[0017] The preparation method of the nickel-based alloy as described above includes the following steps:

[0018] According to stoichiometric requirements, a mixture of elements Al, Cr, Fe, V and Ni is smelted to obtain a master alloy; the master alloy is then cast and heat-treated to obtain a nickel-based alloy.

[0019] In some embodiments, the heat treatment includes solution treatment and aging treatment.

[0020] In some embodiments, an oxide removal process is further included between the casting and the heat treatment.

[0021] In some embodiments, the heat treatment is followed by an oxide layer removal process.

[0022] In some embodiments, the solution treatment temperature is 1040–1060°C, the solution treatment holding time is 3–6 hours, and air cooling is used after the solution treatment.

[0023] In some embodiments, the aging treatment temperature is 730–760°C, the aging treatment holding time is 6–8.5 h, and air cooling is used after the aging treatment.

[0024] The application of nickel-based alloys in spacecraft, as described above.

[0025] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0026] (1) By controlling the elements Al, Cr, Fe, V and Ni in the nickel-based alloy to meet the above-mentioned proportions and limiting the mass percentage of each element to meet the above-mentioned relationship, the present invention ensures that the alloy does not produce harmful phases under long-term exposure at high temperature, has good structural stability, suitable γ' volume fraction and γ' dissolution temperature, has a wide hot working window, and good comprehensive mechanical properties.

[0027] (2) The preparation method of the nickel-based alloy of the present invention is simple and easy to implement, with a low degree of alloying and low alloy preparation cost. The obtained nickel-based alloy has no harmful phase at 650℃, good structural stability, and excellent mechanical properties. Attached Figure Description

[0028] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0029] Figure 1 The image shows the X-ray diffraction (XRD) pattern of the nickel-based alloy in Example 1 of this invention.

[0030] Figure 2 This is a scanning electron microscope image of the nickel-based alloy of Example 2 of the present invention;

[0031] Figure 3 This is a graph showing the change in the volume fraction of the nickel alloy phase as a function of temperature according to the present invention.

[0032] Figure 4 For elemental placeholders in Ni3Al based on first principles;

[0033] Figure 5 This represents the volume change of Ni3AlX based on first-principles calculations. Detailed Implementation

[0034] The embodiments of the present invention will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0035] According to one aspect of the present invention, the present invention relates to a nickel-based alloy comprising, by weight percentage: 4.0% to 5.5% Al, 9.0% to 12.0% Cr, 3.5% to 6.0% Fe, 3.5% to 4.5% V, with the balance being Ni.

[0036] Let the mass percentage of Al be a, the mass percentage of Cr be b, the mass percentage of Fe be c, the mass percentage of V be d, and the mass percentage of Ni be e; m1 = a / 26.98; m2 = b / 52.00; m3 = c / 55.85; m4 = d / 50.94; m5 = e / 58.69.

[0037] M=1.900m1+1.142m2+0.858m3+1.543m4+0.717m5.

[0038] Md=M / (m1+m2+m3+m4+m5), Md<0.94.

[0039] This invention controls the proportions of Al, Cr, Fe, V, and Ni in nickel-based alloys to meet the above-mentioned ratios and limits the mass percentage of each element to meet the above-mentioned relationship. This ensures that the alloy does not produce harmful phases under long-term exposure at high temperatures, has good structural stability, suitable γ' volume fraction and γ' dissolution temperature, a wide hot working window, and good comprehensive mechanical properties.

[0040] In some embodiments, by mass percentage, Al is 4%, 4.2%, 4.5%, 4.8%, 5%, 5.1%, 5.2%, 5.3%, 5.4%, 5.5%, etc., or any range between two values. Cr is 9.0%, 9.2%, 9.5%, 9.8%, 10%, 10.5%, 10.8%, 11%, 11.2%, 11.5%, 11.8%, 12.0%, etc., or any range between two values. Fe is 3.5%, 3.8%, 4%, 4.2%, 4.5%, 4.8%, 5%, 5.5%, 5.8%, 6.0%, etc., or any range between two values. V is 3.5%, 3.8%, 4%, 4.2%, 4.4%, or 4.5%, etc., or any range between two values. Ni can be 75%, 75.5%, 76%, 77%, 78%, 79%, or any value between the two.

[0041] In some implementations, Md is 0.744 to 0.936. In other implementations, the value of Md is 0.744, 0.748, 0.878, 0.921, 0.936, or any value in between.

[0042] In this invention, sufficient solid solution strengthening elements are required to ensure creep resistance. In one embodiment, the total mass percentage of Cr, Fe, and V satisfies the following condition: 18% ≤ b + c + d ≤ 22.5%, for example, 18%, 18.5%, 19%, 19.5%, 20%, 21%, 21.5%, 22%, 22.5%, etc., or any value within a range of two. A suitable total mass percentage of Cr, Fe, and V ensures creep resistance and yields a nickel-based alloy with excellent comprehensive mechanical properties.

[0043] In some embodiments, the ratio of the total mass percentage of Al and Cr to the total mass percentage of Fe and V satisfies the condition: 1.35 ≤ (a+b) / (c+d) ≤ 2.44, for example, 1.35, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, or 2.44. This invention ensures that the nickel-based alloy has suitable oxidation resistance by limiting (a+b) / (c+d) to the above range. Further optimization of (a+b) / (c+d) within a suitable range is more conducive to ensuring the excellent oxidation resistance of the nickel-based alloy.

[0044] In some embodiments, the nickel-based alloy has zero harmful phase content at 650°C and exhibits good structural stability.

[0045] In some embodiments, the volume fraction of the γ' phase in the nickel-based alloy at 750°C is 40%–55%, such as 40%, 42%, 45%, 48%, 50%, 52%, 55%, or any value between the two. The suitable volume fraction of the γ' phase in the nickel-based alloy at 750°C ensures that the nickel-based alloy possesses excellent comprehensive mechanical properties.

[0046] In some embodiments, the γ' dissolution temperature of the nickel-based alloy is below 1100°C, for example, 1000°C, 1020°C, 1050°C, 1070°C, 1080°C, 1090°C, or any value in between. The nickel-based alloy of the present invention has a wide hot working window.

[0047] The preparation method of the nickel-based alloy as described above includes the following steps:

[0048] According to stoichiometric requirements, a mixture of elements Al, Cr, Fe, V and Ni is smelted to obtain a master alloy; the master alloy is then cast and heat-treated to obtain a nickel-based alloy.

[0049] The preparation method of the nickel-based alloy of the present invention is simple and easy to implement, with a low degree of alloying and low alloy preparation cost. The obtained nickel-based alloy has no harmful phases at 650℃, good structural stability, and excellent mechanical properties.

[0050] In some implementations, the purity of elements Al, Cr, Fe, V, and Ni is greater than or equal to 99.99%.

[0051] In some embodiments, the heat treatment includes solution treatment and aging treatment. The solution treatment temperature is 1040–1060°C, for example, 1040°C, 1045°C, 1050°C, 1055°C, 1060°C, or any value between the two. The solution treatment holding time is 3–6 hours, for example, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, 5.5 hours, or 6 hours, or any value between the two. Air cooling (AC) is used after the solution treatment. The aging treatment temperature is 730–760℃, for example, 730℃, 735℃, 740℃, 745℃, 750℃, 755℃, 760℃, or any value within a range of two. The holding time for the aging treatment is 6–8.5 hours, for example, 6 hours, 6.5 hours, 7 hours, 7.5 hours, 8 hours, or 8.5 hours, or any value within a range of two. Air cooling is used after the aging treatment. This invention, through suitable heat treatment conditions, ensures the stability of the nickel-based alloy structure and improves its mechanical properties.

[0052] In some embodiments, an oxide removal process is included between the casting and the heat treatment. In some embodiments, an oxide removal process is included after the heat treatment. The oxide removal process is performed by polishing.

[0053] In some embodiments, the method for preparing the nickel-based alloy of the present invention further includes a method for designing the nickel-based alloy, comprising the following steps:

[0054] A 32-atom 2×2×2 supercell was constructed, in which nickel (Ni) or aluminum (Al) atoms were substituted with elements at a doping concentration of 3.125%. All systems were calculated using CASTE with spin polarization. A cutoff energy of 500 eV was used. The electron exchange correlation function between PW91 and GGA was used. Brillouin zone sampling was performed using a 6×6×6 k-point grid. The energy convergence of the SCF was 5×10⁻⁶. -7 eV / atom. After relaxation, the forces on all atoms are less than [amount missing].

[0055] Formulas (1), (2), (3), (4), and (5) are used to calculate the doping atom occupancy.

[0056] Formula (1):

[0057] Formula (2):

[0058] Formula (3):

[0059] Formula (4):

[0060] Formula (5):

[0061] In the formula, and It is the system energy where X replaces Al and Ni. The energy of the system where Al replaces Ni is... It is the transfer energy from Ni to Al. These are placeholder parameters.

[0062] The cell volume of the doped system is negative, which is beneficial for creep resistance. Formula (6) is used to calculate...

[0063]

[0064] In the formula V X and It represents the cell volume of Ni3Al-X and Ni3Al.

[0065] V, Cr, and Fe were selected as design elements.

[0066] Elemental occupancy in Ni3Al based on first-principles calculations, such as... Figure 4 As shown. The volume change of Ni3AlX based on first-principles calculations is as follows. Figure 5 As shown.

[0067] This design method avoids the high time and economic costs associated with the traditional "trial and error" approach. It accelerates the composition design of materials using cross-scale calculation methods, and designs a new nickel alloy based on first-principles calculations and thermodynamic calculations.

[0068] According to another aspect of the invention, the invention also relates to the application of the aforementioned nickel-based alloy in spacecraft, such as aircraft engines.

[0069] The following explanation, in conjunction with specific embodiments, further clarifies the situation.

[0070] Example 1

[0071] A nickel-based alloy comprising, by weight percentage: Al 5%, Cr 10%, Fe 4%, V 4%, with the balance being Ni (77%).

[0072] The method for preparing the nickel-based alloy described above in this embodiment includes the following steps:

[0073] According to stoichiometric requirements, a mixture of elements Al, Cr, Fe, V, and Ni was melted in a vacuum induction arc furnace to obtain a master alloy. The master alloy was then cast, its surface was polished to remove the oxide layer, and then subjected to heat treatment, including solution treatment and aging treatment. The solution treatment temperature was 1050℃, the holding time was 4 hours, and it was followed by air cooling. The aging treatment temperature was 750℃, the holding time was 8 hours, and it was followed by air cooling to obtain a nickel-based alloy.

[0074] Example 2

[0075] A nickel-based alloy comprising, by weight percentage: Al 5%, Cr 11%, Fe 4%, V 4%, with the balance being Ni (76%).

[0076] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0077] Example 3

[0078] A nickel-based alloy comprising, by weight percentage: Al 4.5%, Cr 9%, Fe 5.5%, V 4.5%, with the balance being Ni (76.5%).

[0079] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0080] Example 4

[0081] A nickel-based alloy comprising, by weight percentage: Al 4.5%, Cr 10.0%, Fe 5.0%, V 4.5%, with the balance being Ni (76%).

[0082] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0083] Example 5

[0084] A nickel-based alloy comprising, by weight percentage: Al 4.5%, Cr 12%, Fe 4.0%, V 4.0%, with the balance being Ni (75.5%).

[0085] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0086] Example 6

[0087] A nickel-based alloy comprising, by weight percentage: Al 5.0%, Cr 9.0%, Fe 5.5%, V 4.0%, with the balance being Ni (76.5%).

[0088] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0089] Example 7

[0090] A nickel-based alloy comprising, by weight percentage: Al 5.0%, Cr 9.0%, Fe 6.0%, V 3.5%, with the balance being Ni (76.5%).

[0091] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0092] Example 8

[0093] A nickel-based alloy comprising, by weight percentage: Al 5.0%, Cr 12.0%, Fe 3.5%, V 3.5%, with the balance being Ni (76%).

[0094] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0095] Example 9

[0096] A nickel-based alloy comprising, by weight percentage: Al 5.0%, Cr 11.0%, Fe 6.0%, V 4.0%, with the balance being Ni (74%).

[0097] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0098] Example 10

[0099] A nickel-based alloy comprising, by weight percentage: Al 5.5%, Cr 10.0%, Fe 6.0%, V 4.5%, with the balance being Ni (74%).

[0100] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0101] The preparation method of the nickel-based alloy described above in this embodiment is the same as that in Example 1, except for the adjustment of the element ratio.

[0102] The mass percentages of each element in the nickel-based alloys in each embodiment are shown in Table 1.

[0103] Table 1. Mass percentage (%) of each element in nickel-based alloys

[0104]

[0105] Let the mass percentage of Al be a, the mass percentage of Cr be b, the mass percentage of Fe be c, the mass percentage of V be d, and the mass percentage of Ni be e.

[0106] Calculate the following values ​​for each embodiment: 1) Md value: m1 = a / 26.98; m2 = b / 52.00; m3 = c / 55.85; m4 = d / 50.94; m5 = e / 58.69; M = 1.900m1 + 1.142m2 + 0.858m3 + 1.543m4 + 0.717m5; Md = M / (m1 + m2 + m3 + m4 + m5). 2) Total mass percentage of Cr, Fe, and V: b + c + d. 3) (a + b) / (c + d). The results are shown in Table 2.

[0107] Table 2 Md, b+c+d, and (a+b) / (c+d)

[0108]

[0109]

[0110] Experimental Example

[0111] The X-ray diffraction pattern of the nickel-based alloy in Example 1 of this invention is as follows: Figure 1 As shown, there are no harmful phases in nickel-based alloys.

[0112] The scanning electron microscope image of the nickel-based alloy in Example 2 of this invention is shown below. Figure 2 As shown.

[0113] The curve of the volume fraction of the nickel alloy phase in this invention as a function of temperature is shown in the figure below. Figure 3 As shown.

[0114] The volume fraction of γ' at 750°C, the dissolution temperature of γ', and the content of harmful phase at 650°C for each embodiment were calculated using Thermo-Calc. The test results are shown in Table 3.

[0115] Table 3 Test results of nickel-based alloys

[0116]

[0117] As shown in Tables 1 to 3, by controlling the appropriate proportions of Al, Cr, Fe, V, and Ni in the nickel-based alloy and limiting the Md value, b+c+d, and (a+b) / (c+d) to a suitable range, this invention can ensure that the alloy does not produce harmful phases under long-term exposure at a high temperature of 650℃, has good structural stability, a γ' volume fraction of 40% to 55%, a γ' dissolution temperature of 1000 to 1100℃, a wide hot working window, and good comprehensive mechanical properties.

[0118] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nickel-based alloy, characterized in that, By mass percentage, it comprises: Al 4.0%~5.5%, Cr 9.0%~12.0%, Fe 3.5%~6.0%, V 3.5%~4.5%, with the balance being Ni; Let the mass percentage of Al be a, the mass percentage of Cr be b, the mass percentage of Fe be c, the mass percentage of V be d, and the mass percentage of Ni be e; m1=a / 26.98; m2=b / 52.00; m3=c / 55.85; m4=d / 50.94; m5=e / 58.69; M=1.900m1+1.142m2+0.858m3+1.543m4+0.717m5; Md = M / (m1 + m2 + m3 + m4 + m5), and Md < 0.94; The total mass percentage of Cr, Fe, and V satisfies: 18% ≤ b + c + d ≤ 22.5%; The ratio of the total mass percentage of Al and Cr to the total mass percentage of Fe and V satisfies: 1.35 ≤ (a+b) / (c+d) ≤ 2.44; The content of harmful phases in the nickel-based alloy at 650°C is 0. The volume fraction of the γ' phase in the nickel-based alloy at 750°C is 40%~55%. The γ' dissolution temperature of the nickel-based alloy is below 1100℃.

2. The method for preparing the nickel-based alloy as described in claim 1, characterized in that, Includes the following steps: According to stoichiometric requirements, a mixture of elements Al, Cr, Fe, V and Ni is smelted to obtain a master alloy; The master alloy is cast and then heat-treated to obtain a nickel-based alloy.

3. The method for preparing the nickel-based alloy according to claim 2, characterized in that, It includes at least one of the following features (1) to (3): (1) The heat treatment includes solution treatment and aging treatment; (2) The process between casting and heat treatment also includes deoxidation treatment; (3) The heat treatment also includes deoxidation treatment.

4. The method for preparing the nickel-based alloy according to claim 3, characterized in that, The solution treatment temperature is 1040~1060℃, the solution treatment holding time is 3~6h, and the solution treatment is followed by air cooling; And / or, the aging treatment temperature is 730~760℃, the aging treatment holding time is 6~8.5h, and the aging treatment is followed by air cooling.

5. The application of the nickel-based alloy as described in claim 1 in spacecraft.

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