Nickel-based alloy and preparation method and application thereof

Abstract

The invention relates to the technical field of nickel alloy materials, in particular to a nickel-based alloy and a preparation method and application thereof. The invention relates to a nickel-based alloy which comprises the following components in percentage by mass: 4.0%-5.5% of Al, 9.0%-12.0% of Cr, 3.5%-6.0% of Fe, 3.5%-4.5% of V and the balance of Ni. According to the invention, elements Al, Cr, Fe, V and Ni in the nickel-based alloy are controlled to meet the dosage proportion, and the mass percentage of each element is limited to meet Md = M / (m1 + m2 + m3 + m4 + m5) lt; and 0.94, it is guaranteed that the alloy does not generate harmful phases under long-time exposure under the high-temperature condition, the structure stability is good, the gamma'volume fraction and the gamma 'dissolution temperature are appropriate, a wide hot working window is achieved, and the comprehensive mechanical property is good.

Description

Technical Field

[0001] The present invention relates to the technical field of nickel alloy materials, and in particular to a nickel-based alloy and a preparation method and application thereof. Background Art

[0002] Nickel alloys have excellent high temperature strength, good oxidation resistance and hot corrosion resistance, good fatigue performance and fracture toughness. High temperature materials require that the material has a significant ability to maintain its properties at high temperatures, and its significant feature is the ability to withstand loads at operating temperatures close to its melting point. If the operating temperature is expressed as T oper and melting point T m , then define the corresponding temperature τ=T oper / T m , then the actual application proves that τ is greater than about 0.6. Based on this theory, in the process of searching for this high temperature material, it was found that the τ corresponding to nickel (melting point 1455℃) working at 1000℃ is (1000+273) / (1455+273)~0.75. Therefore, nickel was selected as a material for high temperature environment application.

[0003] Nickel alloys use γ'-Ni3Al as the second phase to form precipitation strengthening. Improving the performance of the γ'-Ni3Al phase is beneficial to improving the performance of nickel alloys. The excellent mechanical properties of nickel alloys are the guarantee for the stable operation of aircraft engines and the key link in promoting the development of aviation. Therefore, the excellent mechanical properties of nickel-based high-temperature alloys are of great significance to the development of my country's aerospace industry. The development of new nickel alloy strengthening systems will help the production and development of my country's aviation and aerospace industries.

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

[0005] An object of the present invention is to provide a nickel-based alloy which 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 has good comprehensive mechanical properties.

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

[0007] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

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

[0009] Assume that the mass percentage of Al is a, the mass percentage of Cr is b, the mass percentage of Fe is c, the mass percentage of V is d, and the mass percentage of Ni is 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 implementations, the ratio of the total mass percentage of the Al and the Cr to the total mass percentage of the Fe and the V satisfies: 1.35≤(a+b) / (c+d)≤2.44.

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

[0015] In some embodiments, the volume fraction of the γ' phase of 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 lower than 1100°C.

[0017] The method for preparing the nickel-based alloy as described above comprises the following steps:

[0018] According to the 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.

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

[0020] In some implementations, an oxidation layer removal treatment is further performed between the pouring and the heat treatment.

[0021] In some embodiments, the heat treatment further includes an oxidation layer removal treatment.

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

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

[0024] As mentioned above, nickel-based alloys are used in spacecraft.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] (1) The present invention controls the elements Al, Cr, Fe, V and Ni in the nickel-based alloy to meet the above-mentioned usage ratio, and limits the mass percentage of each element to meet the above-mentioned relationship, thereby ensuring that the alloy does not produce harmful phases under long-term exposure to high temperature conditions, has good structural stability, and has a suitable γ' volume fraction and γ' dissolution temperature, 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, the alloying degree is low, the alloy preparation cost is low, and the obtained nickel-based alloy has no harmful phase at 650° C., good organizational stability, and excellent mechanical properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 is the X-ray diffraction pattern (XRD) of the nickel-based alloy of Example 1 of the present invention;

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

[0031] Figure 3 is a curve diagram showing the change of the volume fraction of the nickel alloy phase with temperature of the present invention;

[0032] Figure 4 The element occupancy in Ni3Al based on first principles;

[0033] Figure 5 Volume change of Ni3AlX based on first principles. DETAILED DESCRIPTION

[0034] The embodiments of the present invention will be described in detail below in conjunction with the examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. If no specific conditions are specified in the examples, the conditions are carried out according to normal conditions or the conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be obtained commercially.

[0035] According to one aspect of the present invention, the present invention relates to a nickel-based alloy, which comprises, by mass 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, and the balance is Ni.

[0036] Assume that the mass percentage of Al is a, the mass percentage of Cr is b, the mass percentage of Fe is c, the mass percentage of V is d, and the mass percentage of Ni is 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] The present invention controls the elements Al, Cr, Fe, V and Ni in the nickel-based alloy to meet the above-mentioned usage ratio, and limits the mass percentage of each element to meet the above-mentioned relationship, thereby ensuring that the alloy does not produce harmful phases when exposed for a long time under high temperature conditions, has good organizational stability, suitable γ' volume fraction and γ' dissolution temperature, has a wide hot working window, and has good comprehensive mechanical properties.

[0040] In some embodiments, in terms of 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 them. 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 them. 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 them. V is 3.5%, 3.8%, 4%, 4.2%, 4.4%, 4.5%, etc., or any range between them. Ni is 75%, 75.5%, 76%, 77%, 78%, 79%, etc., or any range between two values.

[0041] In some embodiments, Md is 0.744 to 0.936. In some embodiments, the value of Md is 0.744, 0.748, 0.878, 0.921, 0.936, etc., or any range between the two.

[0042] In the present invention, in order to ensure creep resistance, sufficient solid solution strengthening elements are required. In one embodiment, the total mass percentage of Cr, Fe and V satisfies: 18% ≤ b + c + d ≤ 22.5%, such as 18%, 18.5%, 19%, 19.5%, 20%, 21%, 21.5%, 22%, 22.5%, etc., or any range between the two. Cr, Fe and V have a suitable total mass percentage, thereby ensuring creep resistance and obtaining a nickel-based alloy with excellent comprehensive mechanical properties.

[0043] In some embodiments, the ratio of the total mass percentage of the Al and the Cr to the total mass percentage of the Fe and the V satisfies: 1.35≤(a+b) / (c+d)≤2.44, such as 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. The present invention limits (a+b) / (c+d) to the above range to ensure that the nickel-based alloy has suitable oxidation resistance. It is further preferred that (a+b) / (c+d) is within a suitable range, which is more conducive to ensuring the excellent oxidation resistance of the nickel-based alloy.

[0044] In some embodiments, the harmful phase content of the nickel-based alloy at 650° C. is 0, and the structural stability is good.

[0045] In some embodiments, the volume fraction of the γ' phase of the nickel-based alloy at 750°C is 40% to 55%, such as 40%, 42%, 45%, 48%, 50%, 52%, 55%, etc., or any range between the two. The volume fraction of the γ' phase of the nickel-based alloy at 750°C is appropriate, thereby ensuring that the nickel-based alloy has excellent comprehensive mechanical properties.

[0046] In some embodiments, the γ' dissolution temperature of the nickel-based alloy is lower than 1100° C., such as 1000° C., 1020° C., 1050° C., 1070° C., 1080° C., 1090° C., etc., or any range therebetween. The nickel-based alloy of the present invention has a wide hot working window.

[0047] The method for preparing the nickel-based alloy as described above comprises the following steps:

[0048] According to the 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.

[0049] The preparation method of the nickel-based alloy of the invention is simple and easy, the alloying degree is low, the alloy preparation cost is low, and the obtained nickel-based alloy has no harmful phase at 650° C., good organizational stability, and excellent mechanical properties.

[0050] In some embodiments, the purity of the 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 temperature of the solution treatment is 1040-1060°C, such as 1040°C, 1045°C, 1050°C, 1055°C, °1060C, etc., or any range between the two. The holding time of the solution treatment is 3-6h, such as 3h, 3.5h, 4h, 4.5h, 5h, 5.5h or 6h, etc., or any range between the two. Air cooling (AC) is used after the solution treatment. The temperature of the aging treatment is 730-760°C, such as 730°C, 735°C, 740°C, 745°C, 750°C, 755°C, 760°C, etc., or any range between the two, the holding time of the aging treatment is 6-8.5h, such as 6h, 6.5h, 7h, 7.5h, 8h or 8.5h, etc., or any range between the two, and air cooling is adopted after the aging treatment. The present invention ensures the stability of the nickel-based alloy structure and improves its mechanical properties through suitable heat treatment conditions.

[0052] In some embodiments, the oxide layer removal process is further performed between the pouring and the heat treatment. In some embodiments, the oxide layer removal process is further performed after the heat treatment. The oxide layer removal process is performed by grinding.

[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 with elements replacing nickel (Ni) or aluminum (Al) atoms with a doping concentration of 3.125%. All systems were calculated using CASTE and spin polarization was used. A cutoff energy of 500 eV was used. PW91 and GGA electron exchange correlation functions. A 6×6×6 k-point grid was used for Brillouin zone sampling. The energy convergence of SCF was 5×10 -7 eV / atom. After relaxation, the forces on all atoms are less than

[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 is the system energy of X replacing Al and Ni, is the system energy of Al replacing Ni, is the transfer energy from Ni to Al, It is a placeholder expression parameter.

[0062] The unit cell volume of the doped system is negative, which is beneficial to creep resistance. Calculated using formula (6)

[0063]

[0064] Where V X and is the unit cell volume of Ni3Al-X and Ni3Al.

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

[0066] The element occupancy in Ni3Al based on first principles is as follows Figure 4 The volume change of Ni3AlX based on first principles is shown in Figure 5 shown.

[0067] This design method can avoid the high time and economic costs brought by the traditional "trial and error method". The material uses a cross-scale calculation method to accelerate the composition design, a nickel alloy method based on first principles calculations and thermodynamic calculations, and designs a new nickel alloy.

[0068] According to another aspect of the present invention, the present invention also relates to the application of the nickel-based alloy in a spacecraft, such as an aeroengine.

[0069] The following is further explained in conjunction with specific embodiments.

[0070] Example 1

[0071] A nickel-based alloy comprises, by mass percentage, 5% Al, 10% Cr, 4% Fe, 4% V, and the balance being Ni (77%).

[0072] The method for preparing the nickel-based alloy of the present embodiment comprises the following steps:

[0073] According to the stoichiometric requirements, a mixture of elements Al, Cr, Fe, V and Ni is melted in a vacuum induction arc furnace to obtain a master alloy. The master alloy is cast, the surface is polished, the oxide layer is removed, and then heat-treated, the heat treatment includes solid solution treatment and aging treatment, the temperature of the solid solution treatment is 1050°C, the holding time of the solid solution treatment is 4h, and air cooling is used after the solid solution treatment; the temperature of the aging treatment is 750°C, the holding time of the aging treatment is 8h, and air cooling is used after the aging treatment to obtain a nickel-based alloy.

[0074] Example 2

[0075] A nickel-based alloy comprises, by mass percentage, 5% Al, 11% Cr, 4% Fe, 4% V, and the balance being Ni (76%).

[0076] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 4.5% Al, 9% Cr, 5.5% Fe, 4.5% V, and the balance being Ni (76.5%).

[0079] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 4.5% Al, 10.0% Cr, 5.0% Fe, 4.5% V, and the balance being Ni (76%).

[0082] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 4.5% Al, 12% Cr, 4.0% Fe, 4.0% V, and the balance being Ni (75.5%).

[0085] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 5.0% Al, 9.0% Cr, 5.5% Fe, 4.0% V, and the balance being Ni (76.5%).

[0088] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 5.0% Al, 9.0% Cr, 6.0% Fe, 3.5% V, and the balance is Ni (76.5%).

[0091] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 5.0% Al, 12.0% Cr, 3.5% Fe, 3.5% V, and the balance is Ni (76%).

[0094] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 5.0% Al, 11.0% Cr, 6.0% Fe, 4.0% V, and the balance being Ni (74%).

[0097] The preparation method of the nickel-based alloy 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 comprises, by mass percentage, 5.5% Al, 10.0% Cr, 6.0% Fe, 4.5% V, and the balance being Ni (74%).

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

[0102] The mass percentage of each element in the nickel-based alloy in each embodiment is shown in Table 1.

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

[0104]

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

[0106] Calculation of 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 2Md, b+c+d and (a+b) / (c+d)

[0108]

[0109]

[0110] Experimental example

[0111] The X-ray diffraction pattern of the nickel-based alloy of Example 1 of the present invention is as follows: Figure 1 As shown, it can be seen that there is no harmful phase in the nickel-based alloy.

[0112] The scanning electron microscope image of the nickel-based alloy of Example 2 of the present invention is as follows: Figure 2 shown.

[0113] The curve of the change of the volume fraction of the nickel alloy phase of the present invention with temperature is as follows: Figure 3 shown.

[0114] The volume fraction of γ' at 750°C, the dissolution temperature of γ', and the harmful phase content at 650°C of 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 can be seen from Tables 1 to 3, the present invention controls the elements Al, Cr, Fe, V and Ni in the nickel-based alloy to meet appropriate dosage ratios, and limits the Md value, b+c+d and (a+b) / (c+d) within appropriate ranges, thereby ensuring that the alloy does not produce harmful phases when exposed to high temperature conditions of 650°C for a long time, has good structural stability, a γ' volume fraction of 40% to 55%, a γ' dissolution temperature of 1000 to 1100°C, has a wide hot working window, and has 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, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nickel-based alloy, characterized in that: In terms of mass percentage, it comprises: Al 4.0% to 5.5%, Cr 9.0% to 12.0%, Fe 3.5% to 6.0%, V 3.5% to 4.5%, and the balance is Ni; Assume that the mass percentage of Al is a, the mass percentage of Cr is b, the mass percentage of Fe is c, the mass percentage of V is d, and the mass percentage of Ni is 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.

2. The nickel-based alloy according to claim 1, characterized in that The total mass percentage of the Cr, the Fe and the V satisfies: 18%≤b+c+d≤22.5%.

3. The nickel-based alloy according to claim 1, characterized in that The ratio of the total mass percentage of the Al and the Cr to the total mass percentage of the Fe and the V satisfies: 1.35≤(a+b) / (c+d)≤2.

44.

4. The nickel-based alloy according to claim 1, characterized in that The harmful phase content of the nickel-based alloy at 650° C. is 0.

5. The nickel-based alloy according to claim 1, characterized in that The volume fraction of the γ' phase of the nickel-based alloy at 750° C. is 40% to 55%.

6. The nickel-based alloy according to claim 1, characterized in that The γ' dissolution temperature of the nickel-based alloy is lower than 1100°C.

7. The method for preparing a nickel-based alloy according to any one of claims 1 to 6, characterized in that: The following steps are involved: According to the 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.

8. The method for preparing a nickel-based alloy according to claim 7, characterized in that: Contains at least one of the following features (1) to (3): (1) The heat treatment includes solution treatment and aging treatment; (2) a treatment for removing the oxidation layer is also included between the pouring and the heat treatment; (3) The heat treatment further includes a treatment for removing the oxidation layer.

9. The method for preparing a nickel-based alloy according to claim 8, characterized in that: The temperature of the solution treatment is 1040-1060°C, the holding time of the solution treatment is 3-6h, and air cooling is adopted after the solution treatment; And / or, the temperature of the aging treatment is 730-760° C., the holding time of the aging treatment is 6-8.5 h, and air cooling is adopted after the aging treatment.

10. Use of the nickel-based alloy according to any one of claims 1 to 6 in a spacecraft.

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