Low-cost nickel-based high-temperature alloy and preparation method thereof

Abstract

The invention provides a low-cost nickel-based high-temperature alloy and a preparation method thereof. The low-cost nickel-based high-temperature alloy comprises the following components in percentage by weight: 55%-65% of Ni, 12%-18% of Cr, 8%-15% of Fe, 3%-7% of Mo, 1%-3% of Al, 0.5%-2% of Ti, 0.5%-2% of Nb, 0.01%-0.1% of B and the balance of inevitable impurities. According to the low-cost nickel-based high-temperature alloy and the preparation method thereof, by reasonably adjusting alloy components, the usage amount of expensive elements such as cobalt and tungsten is reduced, meanwhile, relatively cheap iron is ingeniously used for replacing part of nickel, on the premise that the alloy performance requirement is met, the raw material cost is greatly reduced, and the alloy is high in tensile strength and good in mechanical property. And the anti-oxidation performance is good, and the use requirements under numerous medium-high temperature working conditions, such as manufacturing of key parts of equipment such as industrial boilers and heat exchangers, can be met.

Description

Technical Field

[0001] This invention relates to the field of high-temperature alloys, and more particularly to a low-cost nickel-based high-temperature alloy and its preparation method. Background Technology

[0002] Nickel-based superalloys play an indispensable role in many key fields such as aerospace and energy power due to their excellent strength, oxidation resistance and corrosion resistance in high-temperature environments.

[0003] However, traditional nickel-based superalloys often incorporate large amounts of expensive alloying elements such as cobalt, tungsten, and molybdenum, resulting in high manufacturing costs. This not only limits their widespread application in cost-sensitive industries but also hinders the large-scale development of related industries. For example, in the manufacturing of hot-end components for industrial gas turbines, excessively high alloy costs significantly increase the overall cost of the equipment, thereby affecting its market competitiveness and the speed of its widespread adoption.

[0004] Meanwhile, existing methods for preparing nickel-based superalloys are often complex and lengthy, requiring expensive equipment and specific operating environments, which further increases production costs and difficulty, hindering large-scale industrial production.

[0005] Therefore, it is necessary to provide a low-cost nickel-based superalloy and its preparation method to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a low-cost nickel-based superalloy and its preparation method, solving the problems in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides a low-cost nickel-based superalloy, which comprises the following components by weight percentage:

[0008] Ni: 55-65%, Cr: 12-18%, Fe: 8-15%, Mo: 3-7%, Al: 1-3%, Ti: 0.5-2%, Nb: 0.5-2%, B: 0.01-0.1%, balance being unavoidable impurities.

[0009] Ni, as a matrix element, provides the alloy with good high-temperature stability and basic strength.

[0010] Cr can form a dense oxide film on the surface of alloys, which significantly improves the alloy's oxidation and corrosion resistance. When its content is in the range of 12-18%, it can ensure good protective effect without affecting other properties due to excessive content.

[0011] The addition of Fe has replaced some of the expensive Ni to a certain extent, reducing costs. At the same time, an appropriate amount of Fe helps improve the processing performance of the alloy. Experiments have verified that a content range of 8-15% can better balance cost and performance.

[0012] Mo can enhance the high-temperature strength and creep resistance of alloys, and a proportion of 3-7% can achieve effective strengthening while controlling costs.

[0013] Al and Ti work together to strengthen the alloy by forming the γ' phase, thereby improving the alloy's high-temperature strength and hardness. The contents of Al and Ti are controlled at 1-3% and 0.5-2% respectively to ensure the reasonable formation and distribution of the γ' phase.

[0014] Nitrogen (Nb) can refine grains and further improve the overall performance of the alloy. A content of 0.5-2% helps to optimize the microstructure of the alloy.

[0015] Although boron is present in very small amounts, it strengthens grain boundaries and improves the durability of alloys. Even a trace addition of 0.01-0.1% can have a significant effect.

[0016] Preferably, the components, by weight percentage, are: Ni: 58-62%, Cr: 14-16%, Fe: 10-13%, Mo: 4-6%, Al: 1.5-2.5%, Ti: 1-1.8%, Nb: 1-1.8%, B: 0.03-0.08%, with the balance being unavoidable impurities.

[0017] Preferably, the components, by weight percentage, are: Ni: 58-62%, Cr: 14-16%, Fe: 10-13%, Mo: 4-6%, Al: 1.5-2.5%, Ti: 1-1.8%, Nb: 1-1.8%, B: 0.03-0.08%, with the balance being unavoidable impurities.

[0018] This invention also provides a method for preparing a low-cost nickel-based superalloy, comprising the following steps:

[0019] S1. Raw material preparation: Select high-purity Ni, Cr, Fe, Mo, Al, Ti, Nb, and B metal raw materials, with the purity of nickel not less than 99.9% and the purity of other metal raw materials not less than 99.5%. Weigh these raw materials accurately according to their weight percentage, with the error controlled within ±0.1%.

[0020] S2. Pretreatment: Ultrasonic cleaning is performed on the raw materials to remove surface oil, oxides and impurities. After cleaning, the raw materials are placed in a vacuum drying oven to ensure that the surface of the raw materials is dry and clean.

[0021] S3. Vacuum Induction Melting: Place the pretreated raw materials into a vacuum induction melting furnace and evacuate the furnace until the pressure is below 1×10⁻⁶. -3 Pa, then argon gas is introduced as a protective gas to maintain the pressure inside the furnace at 0.1-0.5 MPa, and the induction heating device is turned on to completely melt the raw materials;

[0022] S4. Rapid solidification: A new type of double-roller rapid solidification technology is adopted. The molten alloy liquid is introduced into the space between two high-speed rotating cooling rollers through a guide pipe. When the alloy liquid passes through the cooling rollers, it is subjected to strong cooling and solidifies rapidly to form a thin strip or sheet.

[0023] S5. Hot Isostatic Pressing: The rapidly solidified alloy strip or sheet is placed in a hot isostatic pressing apparatus for hot isostatic pressing.

[0024] S6. Heat treatment: Solution treatment and aging treatment are performed on the alloy after hot isostatic pressing.

[0025] S7. Surface treatment: A nanoscale anti-oxidation coating is prepared on the alloy surface using magnetron sputtering technology;

[0026] S8. Performance Testing: Perform various performance tests on the prepared nickel-based superalloy, including room temperature tensile properties, high temperature tensile properties, oxidation resistance, and corrosion resistance.

[0027] Preferably, the drying temperature in step S2 is 100-150℃, and the drying time is 2-4 hours.

[0028] Preferably, the heating temperature of the induction heating device in S3 is 1500-1700℃, and appropriate stirring is carried out during the melting process to ensure uniform alloy composition.

[0029] Preferably, in step S4, the cooling roller rotates at a speed of 5000-10000 r / min, the roller surface temperature is -50 to 0℃, and the cooling rate is 10. 4 -10 6 ℃ / second.

[0030] Preferably, the temperature of the hot isostatic pressing in S5 is 1100-1300℃, the pressure is 100-200MPa, and the holding time is 2-4h.

[0031] Preferably, in step S6, the solution treatment temperature is 1050-1200℃ and the holding time is 1-3h, the aging treatment temperature is 700-900℃ and the holding time is 8-24h.

[0032] Preferably, the coating material in S7 is Al2O3 or Y2O3, and the coating thickness is 50-100nm.

[0033] Compared with related technologies, the low-cost nickel-based superalloy and its preparation method provided by this invention have the following advantages:

[0034] This invention provides a low-cost nickel-based superalloy and its preparation method. By rationally adjusting the alloy composition, this invention reduces the amount of expensive elements such as cobalt and tungsten, and cleverly uses relatively inexpensive iron to replace part of the nickel. While meeting the alloy performance requirements, it significantly reduces the cost of raw materials. The alloy has high tensile strength and good oxidation resistance, which can meet the requirements of many medium and high temperature conditions, such as the manufacture of key components for industrial boilers, heat exchangers and other equipment. The preparation method is simple and easy to realize industrial production. The alloy has good high-temperature performance and is suitable for large-scale industrial production, which is conducive to further reducing production costs and improving production efficiency. Attached Figure Description

[0035] Figure 1 This is a schematic flowchart of a preferred embodiment of the method for preparing low-cost nickel-based superalloys provided by the present invention. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] Please refer to the following: Figure 1 ,in, Figure 1 This is a schematic flowchart of a preferred embodiment of the method for preparing low-cost nickel-based superalloys provided by the present invention.

[0038] Example 1

[0039] A low-cost nickel-based superalloy comprises the following components by weight percentage:

[0040] Ni: 55%, Cr: 12%, Fe: 8%, Mo: 3%, Al: 1%, Ti: 0.5%, Nb: 0.5%, B: 0.01%, balance being unavoidable impurities.

[0041] A method for preparing a low-cost nickel-based superalloy includes the following steps:

[0042] S1. Raw material preparation: Select high-purity Ni, Cr, Fe, Mo, Al, Ti, Nb, and B metal raw materials, with the purity of nickel not less than 99.9% and the purity of other metal raw materials not less than 99.5%. Weigh these raw materials accurately according to their weight percentage, with the error controlled within ±0.1%.

[0043] S2. Pretreatment: Ultrasonic cleaning is performed on the raw materials to remove surface oil, oxides and impurities. After cleaning, the raw materials are placed in a vacuum drying oven at 100℃ for 2 hours to ensure that the surface of the raw materials is dry and clean.

[0044] S3. Vacuum Induction Melting: Place the pretreated raw materials into a vacuum induction melting furnace and evacuate the furnace until the pressure is below 1×10⁻⁶. -3 Pa, then argon gas is introduced as a protective gas to maintain the pressure inside the furnace at 0.1 MPa, the induction heating device is turned on, and the heating temperature is 1500℃ to completely melt the raw materials. During the melting process, appropriate stirring is carried out to ensure that the alloy composition is uniform.

[0045] S4. Rapid Solidification: A novel twin-roll rapid solidification technology is employed. The molten alloy is introduced through a guide pipe between two high-speed rotating cooling rollers. The cooling rollers rotate at 5000 r / min, and the roller surface temperature is -50℃. As the alloy passes through the cooling rollers, it undergoes intense cooling, achieving a solidification rate of 10... 4 The rapid solidification at a cooling rate of ℃ / second forms a thin ribbon or sheet;

[0046] S5. Hot Isostatic Pressing: The alloy strip or sheet obtained by rapid solidification is placed in a hot isostatic pressing equipment for hot isostatic pressing. The hot isostatic pressing temperature is 1100℃, the pressure is 100MPa, and the holding time is 2h. Through hot isostatic pressing, the porosity and defects in the alloy are eliminated, and the density and mechanical properties of the alloy are improved.

[0047] S6. Heat Treatment: The hot isostatically pressed alloy undergoes solution treatment and aging treatment. The solution treatment temperature is 1050℃, the holding time is 1 hour, and then it is rapidly cooled to room temperature. The aging treatment temperature is 700℃, the holding time is 8 hours, and it is cooled in the furnace. Through heat treatment, the microstructure of the alloy is optimized, further improving the high-temperature strength and oxidation resistance of the alloy.

[0048] S7. Surface treatment: A nanoscale anti-oxidation coating is prepared on the alloy surface using magnetron sputtering technology. The coating material is Al2O3 or Y2O3, and the coating thickness is 50nm. This coating can effectively improve the alloy's anti-oxidation performance and corrosion resistance.

[0049] S8. Performance Testing: Perform various performance tests on the prepared nickel-based superalloy, including room temperature tensile properties, high temperature tensile properties, oxidation resistance, and corrosion resistance.

[0050] Performance test results: The alloy achieved a tensile strength of 620 MPa at 800℃, and after oxidation in air at 800℃ for 100 hours, the oxidation weight gain rate was 0.4 mg / cm³. 2 ·h.

[0051] Example 2

[0052] A low-cost nickel-based superalloy comprises the following components by weight percentage:

[0053] Ni: 60%, Cr: 15%, Fe: 13%, Mo: 5%, Al: 2%, Ti: 1%, Nb: 1.3%, B: 0.05%, balance being unavoidable impurities.

[0054] A method for preparing a low-cost nickel-based superalloy includes the following steps:

[0055] S1. Raw material preparation: Select high-purity Ni, Cr, Fe, Mo, Al, Ti, Nb, and B metal raw materials, with the purity of nickel not less than 99.9% and the purity of other metal raw materials not less than 99.5%. Weigh these raw materials accurately according to their weight percentage, with the error controlled within ±0.1%.

[0056] S2. Pretreatment: Ultrasonic cleaning is performed on the raw materials to remove surface oil, oxides and impurities. After cleaning, the raw materials are placed in a vacuum drying oven at a drying temperature of 130℃ for 3 hours to ensure that the surface of the raw materials is dry and clean.

[0057] S3. Vacuum Induction Melting: Place the pretreated raw materials into a vacuum induction melting furnace and evacuate the furnace until the pressure is below 1×10⁻⁶. -3 Pa, then argon gas is introduced as a protective gas to maintain the pressure inside the furnace at 0.3 MPa, the induction heating device is turned on, and the heating temperature is 1600℃ to completely melt the raw materials. During the melting process, appropriate stirring is carried out to ensure that the alloy composition is uniform.

[0058] S4. Rapid Solidification: A novel twin-roll rapid solidification technology is employed. The molten alloy is introduced through a guide pipe between two high-speed rotating cooling rollers. The cooling rollers rotate at 8000 r / min, and the roller surface temperature is -20℃. As the alloy passes through the cooling rollers, it undergoes intense cooling, achieving a rapid solidification rate of 10... 5 The rapid solidification at a cooling rate of ℃ / second forms a thin ribbon or sheet;

[0059] S5. Hot Isostatic Pressing: The alloy strip or sheet obtained by rapid solidification is placed in a hot isostatic pressing equipment for hot isostatic pressing. The hot isostatic pressing temperature is 1200℃, the pressure is 150MPa, and the holding time is 3h. Through hot isostatic pressing, the porosity and defects in the alloy are eliminated, and the density and mechanical properties of the alloy are improved.

[0060] S6. Heat Treatment: The hot isostatically pressed alloy undergoes solution treatment and aging treatment. The solution treatment temperature is 1130℃, the holding time is 2 hours, and then it is rapidly cooled to room temperature. The aging treatment temperature is 800℃, the holding time is 16 hours, and it is cooled in the furnace. Through heat treatment, the microstructure of the alloy is optimized, further improving the high-temperature strength and oxidation resistance of the alloy.

[0061] S7. Surface treatment: A nanoscale anti-oxidation coating is prepared on the alloy surface using magnetron sputtering technology. The coating material is Al2O3 or Y2O3, and the coating thickness is 70nm. This coating can effectively improve the alloy's anti-oxidation performance and corrosion resistance.

[0062] S8. Performance Testing: Perform various performance tests on the prepared nickel-based superalloy, including room temperature tensile properties, high temperature tensile properties, oxidation resistance, and corrosion resistance.

[0063] Performance test results: The alloy has a tensile strength of 610 MPa at 800℃, and after oxidation in air at 800℃ for 100 hours, the oxidation weight gain rate is 0.45 mg / cm³. 2 ·h.

[0064] Example 3

[0065] A low-cost nickel-based superalloy comprises the following components by weight percentage:

[0066] Ni: 65%, Cr: 18%, Fe: 15%, Mo: 7%, Al: 3%, Ti: %, Nb: 2%, B: 0.1%, balance being unavoidable impurities.

[0067] A method for preparing a low-cost nickel-based superalloy includes the following steps:

[0068] S1. Raw material preparation: Select high-purity Ni, Cr, Fe, Mo, Al, Ti, Nb, and B metal raw materials, with the purity of nickel not less than 99.9% and the purity of other metal raw materials not less than 99.5%. Weigh these raw materials accurately according to their weight percentage, with the error controlled within ±0.1%.

[0069] S2. Pretreatment: Ultrasonic cleaning is performed on the raw materials to remove surface oil, oxides and impurities. After cleaning, the raw materials are placed in a vacuum drying oven at 150℃ for 4 hours to ensure that the surface of the raw materials is dry and clean.

[0070] S3. Vacuum Induction Melting: Place the pretreated raw materials into a vacuum induction melting furnace and evacuate the furnace until the pressure is below 1×10⁻⁶. -3 Pa, then argon gas is introduced as a protective gas to maintain the pressure inside the furnace at 0.5 MPa, the induction heating device is turned on, and the heating temperature is 1700℃ to completely melt the raw materials. During the melting process, appropriate stirring is carried out to ensure that the alloy composition is uniform.

[0071] S4. Rapid Solidification: A novel twin-roll rapid solidification technology is employed. The molten alloy is introduced through a guide pipe between two high-speed rotating cooling rollers. The cooling rollers rotate at 10,000 r / min, and the roller surface temperature is 0℃. As the alloy passes through the cooling rollers, it undergoes intense cooling, achieving a rapid solidification rate of 10... 6 The rapid solidification at a cooling rate of ℃ / second forms a thin ribbon or sheet;

[0072] S5. Hot Isostatic Pressing: The alloy strip or sheet obtained by rapid solidification is placed in a hot isostatic pressing equipment for hot isostatic pressing. The hot isostatic pressing temperature is 1300℃, the pressure is 200MPa, and the holding time is 4h. Through hot isostatic pressing, the porosity and defects in the alloy are eliminated, and the density and mechanical properties of the alloy are improved.

[0073] S6. Heat Treatment: The hot isostatically pressed alloy undergoes solution treatment and aging treatment. The solution treatment temperature is 1200℃, the holding time is 3 hours, and then it is rapidly cooled to room temperature. The aging treatment temperature is 900℃, the holding time is 24 hours, and it is cooled in the furnace. Through heat treatment, the microstructure of the alloy is optimized, further improving the high-temperature strength and oxidation resistance of the alloy.

[0074] S7. Surface treatment: A nanoscale anti-oxidation coating is prepared on the alloy surface using magnetron sputtering technology. The coating material is Al2O3 or Y2O3, and the coating thickness is 100nm. This coating can effectively improve the alloy's anti-oxidation performance and corrosion resistance.

[0075] S8. Performance Testing: Perform various performance tests on the prepared nickel-based superalloy, including room temperature tensile properties, high temperature tensile properties, oxidation resistance, and corrosion resistance.

[0076] Performance test results: The tensile strength of this alloy at 800℃ is 630MPa, and the oxidation weight gain rate after oxidizing in air at 800℃ for 100 hours is 0.38mg / cm³. 2 ·h.

[0077] As can be seen from the above embodiments, the low-cost nickel-based high-temperature alloys prepared by the present invention all have good high-temperature mechanical properties and oxidation resistance, which can meet the needs of practical applications.

[0078] Compared with related technologies, the low-cost nickel-based superalloy and its preparation method provided by this invention have the following advantages:

[0079] This invention reduces the use of expensive elements such as cobalt and tungsten by rationally adjusting the alloy composition, and cleverly uses relatively inexpensive iron to replace part of the nickel. While meeting the alloy performance requirements, it significantly reduces the cost of raw materials. The alloy has high tensile strength and good oxidation resistance, which can meet the requirements of many medium and high temperature conditions, such as the manufacture of key components for industrial boilers, heat exchangers and other equipment. Moreover, the preparation method is simple and easy to realize industrial production. The alloy has good high temperature performance and is suitable for large-scale industrial production, which is conducive to further reducing production costs and improving production efficiency.

[0080] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A low-cost nickel-based superalloy, characterized in that, By weight percentage, it includes the following components: Ni: 55-65%, Cr: 12-18%, Fe: 8-15%, Mo: 3-7%, Al: 1-3%, Ti: 0.5-2%, Nb: 0.5-2%, B: 0.01-0.1%, balance being unavoidable impurities.

2. The low-cost nickel-based superalloy according to claim 1, characterized in that, The components, by weight percentage, are as follows: Ni: 58-62%, Cr: 14-16%, Fe: 10-13%, Mo: 4-6%, Al: 1.5-2.5%, Ti: 1-1.8%, Nb: 1-1.8%, B: 0.03-0.08%, with the balance being unavoidable impurities.

3. The low-cost nickel-based superalloy according to claim 1, characterized in that, The components, by weight percentage, are as follows: Ni: 58-62%, Cr: 14-16%, Fe: 10-13%, Mo: 4-6%, Al: 1.5-2.5%, Ti: 1-1.8%, Nb: 1-1.8%, B: 0.03-0.08%, with the balance being unavoidable impurities.

4. A method for preparing a low-cost nickel-based superalloy, characterized in that, Includes the following steps: S1. Raw material preparation: Select high-purity Ni, Cr, Fe, Mo, Al, Ti, Nb, and B metal raw materials, with the purity of nickel not less than 99.9% and the purity of other metal raw materials not less than 99.5%. Weigh these raw materials accurately according to their weight percentage, with the error controlled within ±0.1%. S2. Pretreatment: Ultrasonic cleaning is performed on the raw materials to remove surface oil, oxides and impurities. After cleaning, the raw materials are placed in a vacuum drying oven to ensure that the surface of the raw materials is dry and clean. S3. Vacuum Induction Melting: Place the pretreated raw materials into a vacuum induction melting furnace and evacuate the furnace until the pressure is below 1×10⁻⁶. -3 Pa, then argon gas is introduced as a protective gas to maintain the pressure inside the furnace at 0.1-0.5 MPa, and the induction heating device is turned on to completely melt the raw materials; S4. Rapid solidification: A new type of double-roller rapid solidification technology is adopted. The molten alloy liquid is introduced into the space between two high-speed rotating cooling rollers through a guide pipe. When the alloy liquid passes through the cooling rollers, it is subjected to strong cooling and solidifies rapidly to form a thin strip or sheet. S5. Hot Isostatic Pressing: The rapidly solidified alloy strip or sheet is placed in a hot isostatic pressing apparatus for hot isostatic pressing. S6. Heat treatment: Solution treatment and aging treatment are performed on the alloy after hot isostatic pressing. S7. Surface treatment: A nanoscale anti-oxidation coating is prepared on the alloy surface using magnetron sputtering technology; S8. Performance Testing: Perform various performance tests on the prepared nickel-based superalloy, including room temperature tensile properties, high temperature tensile properties, oxidation resistance, and corrosion resistance.

5. The method for preparing the low-cost nickel-based superalloy according to claim 4, characterized in that, The drying temperature in S2 is 100-150℃, and the drying time is 2-4 hours.

6. The method for preparing the low-cost nickel-based superalloy according to claim 4, characterized in that, The heating temperature of the induction heating device in S3 is 1500-1700℃, and appropriate stirring is carried out during the melting process to ensure uniform alloy composition.

7. The method for preparing the low-cost nickel-based superalloy according to claim 4, characterized in that, The cooling roller in S4 rotates at a speed of 5000-10000 r / min, has a surface temperature of -50 to 0℃, and a cooling rate of 10. 4 -10 6 ℃ / second.

8. The method for preparing the low-cost nickel-based superalloy according to claim 4, characterized in that, The temperature of the hot isostatic pressing in S5 is 1100-1300℃, the pressure is 100-200MPa, and the holding time is 2-4h.

9. The method for preparing a low-cost nickel-based superalloy according to claim 4, characterized in that, The solution treatment temperature in S6 is 1050-1200℃, and the holding time is 1-3h; the aging treatment temperature is 700-900℃, and the holding time is 8-24h.

10. The method for preparing a low-cost nickel-based superalloy according to claim 4, characterized in that, The coating material in S7 is Al2O3 or Y2O3, and the coating thickness is 50-100nm.

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