A cobalt-nickel based superalloy with high gamma prime phase volume fraction and a method of making the same

Abstract

The application discloses a cobalt-nickel-based high-temperature alloy with high gamma-prime phase volume fraction and a preparation method thereof, and belongs to the technical field of cobalt-based high-temperature alloys. The cobalt-nickel-based high-temperature alloy disclosed by the application comprises a gamma matrix and a gamma-prime phase, and the volume fraction of the gamma-prime phase is 75-83%. The contents of alloy elements Mo and Ta are adjusted to improve the volume fraction of the gamma-prime phase and the organizational stability. The addition of Mo reduces the interface energy of the gamma / gamma-prime two-phase, and further reduces the gamma-prime phase coarsening rate. Meanwhile, the addition of Mo promotes more Ta to be distributed in the gamma-prime phase. Ta is a strong gamma-prime phase forming element, and Ta significantly increases the content of the eutectic gamma-prime phase, and further under the synergistic effect of Mo and Ta, the volume fraction of the gamma-prime phase of the alloy is significantly improved.

Description

Technical Field

[0001] This invention belongs to the field of cobalt-based superalloy technology, specifically relating to a cobalt-nickel-based superalloy with a high γ′ phase volume fraction and its preparation method. Background Technology

[0002] High-temperature alloys have a wide range of applications as important high-temperature structural materials in many fields such as chemical engineering, aerospace, and energy. High-temperature alloys can operate at high temperatures of 600℃-1100℃ and have excellent corrosion resistance, thermal fatigue resistance, creep resistance, castability, and weldability, making them very suitable for hot-end components such as aero-engine combustion chambers and large-size blades of heavy-duty gas turbines.

[0003] Novel cobalt-nickel-based alloys utilize precipitation strengthening and coherent strengthening of the coherent γ′ phase to significantly improve the high-temperature strength and ductility of the alloy. Therefore, the volume fraction of the γ′ phase directly affects the heat resistance and high-temperature strength of the novel cobalt-nickel-based superalloy. To meet the performance requirements for high-temperature service, the volume fraction of the γ′ phase can be increased by adding W. However, excessive W content, while increasing the volume fraction of the γ′ phase, will also promote the precipitation of harmful phases such as the W-rich μ phase Co7-W6 and the Al-rich phase, thereby compromising microstructure stability and reducing the alloy's service performance. Therefore, selecting appropriate alloying elements and proportions is crucial for improving the heat resistance, high-temperature strength, and service performance of novel cobalt-nickel-based superalloys.

[0004] Therefore, how to increase the volume fraction of the γ′ phase while ensuring no harmful phase precipitation is an important issue that urgently needs to be studied. Summary of the Invention

[0005] In order to overcome the shortcomings of the prior art, the present invention aims to provide a cobalt-nickel based superalloy with a high γ′ phase volume fraction and its preparation method, so as to solve the technical problem that existing cobalt-nickel based superalloys are difficult to prepare with a suitable γ′ phase volume fraction to meet different working requirements.

[0006] To achieve the above objectives, the present invention employs the following technical solution:

[0007] This invention discloses a cobalt-nickel-based superalloy with a high γ′ phase volume fraction. The composition, by mass percentage, includes: Al: 3.5-4.5%, Ni: 25.0-30.0%, Mo: 2.5-3.5%, Ta: 5.5-6.5%, Ti: 3.0-3.5%, W: 5.5-6.5%, with the balance being Co and unavoidable impurities. The sum of the mass percentages of the above components is 100%.

[0008] Further, by mass percentage, the Mo is 3.0-3.5% and the Ta is 5.5-6.0%, wherein the impurity content is not greater than 0.1%.

[0009] This invention also discloses a method for preparing the above-mentioned cobalt-nickel-based superalloy with a high γ′ phase volume fraction, comprising the following steps:

[0010] S1: Calculate and weigh the raw materials of pure metals Co, Al, Ni, Ti, Mo, Ta and cobalt-tungsten alloy according to their mass percentages and configure the amount of each element.

[0011] S2: Place the prepared alloy raw materials into a container inside the vacuum arc melting furnace, place a titanium block in the empty space of the container, evacuate the vacuum, and then introduce inert gas.

[0012] S3: Adjust the position of the container so that the titanium block is facing the arc gun, adjust the distance between the arc gun and the titanium block, start igniting the arc, and melt the titanium block after successful arc ignition.

[0013] S4: Adjust the position of the container so that the sample is facing the arc gun, adjust the distance between the arc gun and the titanium block, start the arc ignition, and after the arc is successfully ignited, increase the arc current and use a magnetic stirrer to fully mix the raw materials. After the melting is completed, an alloy ingot is obtained.

[0014] S5: The alloy ingot is solution treated and then aged to obtain a cobalt-nickel-based superalloy with a high γ′ phase volume fraction.

[0015] Furthermore, in S1, the cobalt-tungsten alloy composition is selected as Co:W = 3:2 by mass percentage.

[0016] Furthermore, S2 includes the following steps: placing the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace, placing a metallic titanium block in the empty crucible position, starting to evacuate the vacuum after the loading is completed, and introducing high-purity argon gas for gas washing; after evacuating the low vacuum again, turning on the molecular pump to evacuate the high vacuum until the high vacuum degree is less than 4*10-3Pa, and introducing high-purity argon gas into the furnace cavity again.

[0017] The process of drawing a low vacuum requires ensuring that the gas pressure inside the furnace is less than -0.1 MPa, and then introducing high-purity argon gas until the gas pressure inside the furnace reaches 0.08 MPa.

[0018] Furthermore, in S3 and S4, the distance between the arc gun and the titanium block is adjusted to 1-2 mm; the arc current is set to 50A and the arc is started; after successful arc ignition, the arc current is increased to 100A and 200A respectively to completely melt the titanium.

[0019] Furthermore, in S4, after successful arc ignition, the arc gun is raised to 15cm, and the arc current is increased to 100A while the arc gun is rotated clockwise at a speed of 5.0° / s; while increasing the arc current to 200A, the magnetic stirring device is turned on and the magnetic stirring current is set to 5A; the arc current is increased to 500A, and the melting time is not less than 1 minute.

[0020] Furthermore, in S4, to ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting process, and then cooled to obtain an alloy ingot.

[0021] After one melting cycle, the sample is flipped over using a pusher and melted again. Each sample needs to be melted 4 times. After melting, wait for the alloy ingot to cool down to room temperature, open the gas filling valve, and open the furnace door after the gas pressure in the furnace chamber returns to atmospheric pressure.

[0022] Furthermore, in S5, the solution treatment temperature is 1250℃, the time is 10h, the heating rate is 10℃ / min, the holding time is 10h, and the cooling method is air cooling.

[0023] Furthermore, in S5, the aging treatment temperature is 900℃ and the time is 100h.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] This invention discloses a cobalt-nickel-based superalloy with a high γ′ phase volume fraction. In terms of phase composition, the cobalt-nickel-based superalloy includes a γ matrix and a γ′ phase, with the γ′ phase volume fraction being 75-83%. The contents of alloying elements Mo and Ta are adjusted to improve the γ′ phase volume fraction and microstructure stability. The addition of Mo reduces the interfacial energy between the γ / γ′ phases, thereby reducing the coarsening rate of the γ′ phase. Simultaneously, the addition of Mo promotes the distribution of more Ta into the γ′ phase. Ta is also a strong γ′ phase forming element, significantly increasing the content of the eutectic γ′ phase. Therefore, under the synergistic effect of Mo and Ta, the γ′ phase volume fraction of the alloy is significantly increased. Optimizing the γ′ phase volume fraction can further improve the high-temperature mechanical properties of the alloy. Compared with traditional cobalt-based superalloys, the high-temperature mechanical properties of the novel cobalt-nickel-based superalloy mainly rely on the precipitation strengthening effect of the γ′ phase. Therefore, increasing the γ′ phase volume fraction directly improves the creep resistance and temperature resistance of the alloy. Attached Figure Description

[0026] Figure 1 Images showing the microstructure of the cobalt-nickel-based superalloy with a high γ′ phase volume fraction prepared according to the present invention.

[0027] Where: a-2Mo2Ta; b-4Mo1Ta. Detailed Implementation

[0028] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions used in the specification and claims are explained and defined in general below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meaning understood by those skilled in the art regarding the present invention, and in case of conflict, the definitions in this specification shall prevail.

[0029] The theories or mechanisms described and disclosed herein, whether right or wrong, should not in any way limit the scope of the invention, that is, the contents of the invention can be implemented without being limited by any particular theory or mechanism.

[0030] In this document, all features defined by numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are for the sake of brevity and convenience only. Accordingly, descriptions of numerical ranges or percentage ranges should be considered as covering and specifically disclosing all possible sub-ranges and individual numerical values ​​(including integers and fractions) within those ranges.

[0031] In this article, unless otherwise specified, “contains,” “includes,” “containing,” “has,” or similar terms cover the meanings of “composed of” and “mainly composed of,” for example, “A contains a” covers the meanings of “A contains a and others” and “A contains only a.”

[0032] For the sake of brevity, not all possible combinations of the technical features in each implementation scheme or embodiment are described herein. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation scheme or embodiment can be combined arbitrarily, and all possible combinations should be considered within the scope of this specification.

[0033] This invention provides a method for preparing a cobalt-nickel-based superalloy with a high γ′ phase volume fraction, comprising the following steps:

[0034] S1: Pure metals Co, Al, Ni, Ti, Mo, Ta, and cobalt-tungsten alloy are prepared according to the design composition control requirements. The amount of each element raw material is calculated and weighed according to the mass percentage. Ethanol and an ultrasonic cleaner are used to remove grease and contaminants from the surface of the raw materials.

[0035] S2: Place the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace. Place a titanium block in the empty crucible position. After loading, start evacuating the furnace. When the vacuum reaches -0.1 MPa, introduce high-purity argon gas to -0.08 MPa for purging. After evacuating to -0.1 MPa again, turn on the molecular pump to evacuate the furnace to a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas was introduced into the furnace cavity again to -0.07 MPa.

[0036] S3: Adjust the crucible so that the titanium block is facing the arc gun (tungsten electrode). Adjust the distance between the arc gun and the titanium block to 1-2mm. Set the arc current to 50A and start igniting the arc. After successful ignition, melt the titanium block. The molten titanium will further absorb oxygen in the furnace cavity to ensure the purity of the atmosphere in the furnace cavity.

[0037] S4: Adjust the crucible so that the sample is facing the arc gun (tungsten electrode), adjust the distance between the arc gun and the sample to 1-2 mm, set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current and use a magnetic stirrer to fully mix the raw materials. To ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting. After cooling, an alloy ingot is obtained.

[0038] S5: The alloy ingot is placed in a box furnace and solution treated at 1250°C for 10 hours, followed by aging treatment at 900°C for 100 hours to obtain the novel cobalt-nickel-based high-temperature alloy with high γ′ phase volume fraction.

[0039] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. Furthermore, it should be understood that after reading the teachings of this invention, those skilled in the art can make various alterations or modifications to the invention, and these equivalent forms also fall within the scope defined by the appended claims.

[0040] The following examples use instruments and equipment conventional in the art. Experimental methods in the following examples, unless otherwise specified, are generally performed under conventional conditions or as recommended by the manufacturer. All raw materials used in the following examples are conventional commercially available products with specifications conventional in the art. In this specification and the following examples, unless otherwise specified, "%" refers to weight percentage, "parts" refers to parts by weight, and "ratio" refers to weight proportion.

[0041] Example 1

[0042] A method for preparing a cobalt-nickel-based superalloy with a high γ′ phase volume fraction includes the following steps:

[0043] S1: Pure metal Co, pure metal Al, pure metal Ni, pure metal Ti, and cobalt-tungsten alloy are weighed and prepared according to the design composition control requirements, based on the mass percentage of each element: Al: 4.0%, Ni: 28.0%, Ti: 3.0%, W: 6.0%, Ta: 5.5%, with the balance being Co and unavoidable impurities. Ethanol and an ultrasonic cleaner are used to remove grease and contaminants from the surface of the raw materials.

[0044] S2: Place the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace. Place a titanium block in the empty crucible position. After loading, start evacuating the furnace. When the vacuum reaches -0.1 MPa, introduce high-purity argon gas to -0.08 MPa for purging. After evacuating to -0.1 MPa again, turn on the molecular pump to evacuate the furnace to a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas was introduced into the furnace cavity again to -0.07 MPa.

[0045] S3: Adjust the crucible so that the titanium block is facing the arc gun (tungsten electrode). Adjust the distance between the arc gun and the titanium block to 1-2mm. Set the arc current to 50A and start igniting the arc. After successful ignition, melt the titanium block. The molten titanium will further absorb oxygen in the furnace cavity to ensure the purity of the atmosphere in the furnace cavity.

[0046] S4: Adjust the crucible so that the sample is facing the arc gun (tungsten electrode), adjust the distance between the arc gun and the sample to 1-2 mm, set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current and use a magnetic stirrer to fully mix the raw materials. To ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting. After cooling, an alloy ingot is obtained.

[0047] S5: The alloy ingot is placed in a box furnace and solution treated at 1250°C for 10 hours, followed by aging treatment at 900°C for 100 hours to obtain the cobalt-nickel-based high-temperature alloy with high γ′ phase volume fraction.

[0048] Example 2

[0049] A method for preparing a cobalt-nickel-based superalloy with a high γ′ phase volume fraction includes the following steps:

[0050] S1: Pure metals Co, Al, Ni, Ti, Mo, Ta, and cobalt-tungsten alloy are weighed and prepared according to the design composition control requirements, based on the following mass percentages: Al: 4.0%, Ni: 25.0%, Ti: 3.0%, Mo: 5.0%, Ta: 3.5%, W: 6.5%, with the balance being Co and unavoidable impurities. Ethanol and an ultrasonic cleaner are used to remove grease and contaminants from the surface of the raw materials.

[0051] S2: Place the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace. Place a titanium block in the empty crucible position. After loading, start evacuating the furnace. When the vacuum reaches -0.1 MPa, introduce high-purity argon gas to -0.08 MPa for purging. After evacuating to -0.1 MPa again, turn on the molecular pump to evacuate the furnace to a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas was introduced into the furnace cavity again to -0.07 MPa.

[0052] S3: Adjust the crucible so that the titanium block is facing the arc gun (tungsten electrode). Adjust the distance between the arc gun and the titanium block to 1-2mm. Set the arc current to 50A and start igniting the arc. After successful ignition, melt the titanium block. The molten titanium will further absorb oxygen in the furnace cavity to ensure the purity of the atmosphere in the furnace cavity.

[0053] S4: Adjust the crucible so that the sample is facing the arc gun (tungsten electrode), adjust the distance between the arc gun and the sample to 1-2 mm, set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current and use a magnetic stirrer to fully mix the raw materials. To ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting. After cooling, an alloy ingot is obtained.

[0054] S5: The alloy ingot is placed in a box furnace and solution treated at 1250°C for 10 hours, followed by aging treatment at 900°C for 100 hours to obtain the cobalt-nickel-based high-temperature alloy with high γ′ phase volume fraction.

[0055] Example 3

[0056] A method for preparing a cobalt-nickel-based superalloy with a high γ′ phase volume fraction includes the following steps:

[0057] S1: Pure metals Co, Al, Ni, Ti, Mo, Ta, and cobalt-tungsten alloy are prepared according to the design composition control requirements. The raw material amounts of each element are calculated and weighed separately according to the mass percentage: Al: 4.0%, Ni: 28.0%, Mo: 2.5%, Ta: 5.5%, Ti: 3.0%, W: 6.0%, with the balance being Co and unavoidable impurities. Ethanol and an ultrasonic cleaner are used to remove grease and contaminants from the surface of the raw materials.

[0058] S2: Place the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace. Place a titanium block in the empty crucible position. After loading, start evacuating the furnace. When the vacuum reaches -0.1 MPa, introduce high-purity argon gas to -0.08 MPa for purging. After evacuating to -0.1 MPa again, turn on the molecular pump to evacuate the furnace to a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas was introduced into the furnace cavity again to -0.07 MPa.

[0059] S3: Adjust the crucible so that the titanium block is facing the arc gun (tungsten electrode). Adjust the distance between the arc gun and the titanium block to 1-2mm. Set the arc current to 50A and start igniting the arc. After successful ignition, melt the titanium block. The molten titanium will further absorb oxygen in the furnace cavity to ensure the purity of the atmosphere in the furnace cavity.

[0060] S4: Adjust the crucible so that the sample is facing the arc gun (tungsten electrode), adjust the distance between the arc gun and the sample to 1-2 mm, set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current and use a magnetic stirrer to fully mix the raw materials. To ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting. After cooling, an alloy ingot is obtained.

[0061] S5: The alloy ingot is placed in a box furnace and solution treated at 1250°C for 10 hours, followed by aging treatment at 900°C for 100 hours to obtain the cobalt-nickel-based high-temperature alloy with high γ′ phase volume fraction.

[0062] Example 4

[0063] A method for preparing a cobalt-nickel-based superalloy with a high γ′ phase volume fraction includes the following steps:

[0064] S1: Pure metals Co, Al, Ni, Ti, Mo, Ta, and cobalt-tungsten alloy are prepared according to the design composition control requirements. The raw material amounts of each element are calculated and weighed according to the mass percentage: Al: 3.5%, Ni: 25.0%, Mo: 3.5%, Ta: 5.5%, Ti: 3.0%, W: 5.5%, with the balance being Co and unavoidable impurities. Ethanol and an ultrasonic cleaner are used to remove grease and contaminants from the surface of the raw materials.

[0065] S2: Place the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace. Place a titanium block in the empty crucible position. After loading, start evacuating the furnace. When the vacuum reaches -0.1 MPa, introduce high-purity argon gas to -0.08 MPa for purging. After evacuating to -0.1 MPa again, turn on the molecular pump to evacuate the furnace to a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas was introduced into the furnace cavity again to -0.07 MPa.

[0066] S3: Adjust the crucible so that the titanium block is facing the arc gun (tungsten electrode). Adjust the distance between the arc gun and the titanium block to 1-2mm. Set the arc current to 50A and start igniting the arc. After successful ignition, melt the titanium block. The molten titanium will further absorb oxygen in the furnace cavity to ensure the purity of the atmosphere in the furnace cavity.

[0067] S4: Adjust the crucible so that the sample is facing the arc gun (tungsten electrode), adjust the distance between the arc gun and the sample to 1-2 mm, set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current and use a magnetic stirrer to fully mix the raw materials. To ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting. After cooling, an alloy ingot is obtained.

[0068] S5: The alloy ingot is placed in a box furnace and solution treated at 1250°C for 10 hours, followed by aging treatment at 900°C for 100 hours to obtain the cobalt-nickel-based high-temperature alloy with high γ′ phase volume fraction.

[0069] Example 5

[0070] A method for preparing a cobalt-nickel-based superalloy with a high γ′ phase volume fraction includes the following steps:

[0071] S1: Pure metals Co, Al, Ni, Ti, Mo, Ta, and cobalt-tungsten alloy are prepared according to the design composition control requirements. The raw material amounts of each element are calculated and weighed separately according to the mass percentage: Al: 4.5%, Ni: 30.0%, Mo: 3.5%, Ta: 6.5%, Ti: 3.0%, W: 6.5%, with the balance being Co and unavoidable impurities. Ethanol and an ultrasonic cleaner are used to remove grease and contaminants from the surface of the raw materials.

[0072] S2: Place the prepared alloy raw materials into the crucible inside the vacuum arc melting furnace. Place a titanium block in the empty crucible position. After loading, start evacuating the furnace. When the vacuum reaches -0.1 MPa, introduce high-purity argon gas to -0.08 MPa for purging. After evacuating to -0.1 MPa again, turn on the molecular pump to evacuate the furnace to a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas was introduced into the furnace cavity again to -0.07 MPa.

[0073] S3: Adjust the crucible so that the titanium block is facing the arc gun (tungsten electrode). Adjust the distance between the arc gun and the titanium block to 1-2mm. Set the arc current to 50A and start igniting the arc. After successful ignition, melt the titanium block. The molten titanium will further absorb oxygen in the furnace cavity to ensure the purity of the atmosphere in the furnace cavity.

[0074] S4: Adjust the crucible so that the sample is facing the arc gun (tungsten electrode), adjust the distance between the arc gun and the sample to 1-2 mm, set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current and use a magnetic stirrer to fully mix the raw materials. To ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting. After cooling, an alloy ingot is obtained.

[0075] S5: The alloy ingot is placed in a box furnace and solution treated at 1250°C for 10 hours, followed by aging treatment at 900°C for 100 hours to obtain the cobalt-nickel-based high-temperature alloy with high γ′ phase volume fraction.

[0076] The microstructure of the novel cobalt-nickel-based superalloys obtained in Examples 1 to 5 was characterized using scanning electron microscopy. The volume fraction of the γ′ phase in the alloys was determined using Image Pro Plus, and the results are shown in Table 1. From the examples and the results in Table 1, it can be seen that Example 1, the alloy with only Ta added and no Mo added, has the lowest corresponding γ′ phase volume fraction. In the other examples, the addition of Mo and Ta significantly increased the γ′ phase volume fraction, and the scanning images show a high-density γ′ phase uniformly distributed on the γ matrix. The novel cobalt-nickel-based superalloy with Mo and Ta jointly regulated by the present invention exhibits a significantly increased γ′ phase volume fraction.

[0077] Table 1: Volume fraction of γ′ phase

[0078]

[0079] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. A high-γ A method for preparing cobalt-nickel-based superalloys with varying phase volume fractions, characterized in that, Includes the following steps: S1: Calculate and weigh the raw materials of pure metals Co, Al, Ni, Ti, Mo, Ta and cobalt-tungsten alloy according to their mass percentages and configure the amount of each element. S2: Place the prepared alloy raw materials into a container inside the vacuum arc melting furnace, place a titanium block in the empty space of the container, evacuate the vacuum, and then introduce inert gas. S3: Adjust the position of the container so that the titanium block is facing the arc gun, adjust the distance between the arc gun and the titanium block, start igniting the arc, and melt the titanium block after successful arc ignition. S4: Adjust the position of the container so that the sample is facing the arc gun, adjust the distance between the arc gun and the titanium block, start the arc ignition, and after the arc is successfully ignited, increase the arc current and use a magnetic stirrer to fully mix the raw materials. After the melting is completed, an alloy ingot is obtained. S5: The alloy ingot is solution treated, followed by aging treatment to obtain high γ Cobalt-nickel based superalloys with phase volume fraction; In S1, the cobalt-tungsten alloy composition is selected as Co:W=3:2 by mass percentage; S2 includes the following steps: The prepared alloy raw material is placed into the crucible inside the vacuum arc melting furnace; a titanium block is placed in the empty crucible position; after loading, a vacuum is drawn, and high-purity argon gas is introduced for purging; a low vacuum is drawn again, and then a molecular pump is turned on to draw a high vacuum until the high vacuum degree is less than 4*10. -3 Pa, high-purity argon gas is introduced into the furnace cavity again; Among them, the low vacuum process requires ensuring that the gas pressure inside the furnace is less than -0.1MPa, and high-purity argon gas is introduced until the gas pressure inside the furnace reaches 0.08MPa; In S3 and S4, adjust the distance between the arc gun and the titanium block to 1-2 mm; set the arc current to 50A and start igniting the arc; after successful arc ignition, increase the arc current to 100A and 200A respectively to completely melt the titanium. The high γ The cobalt-nickel-based superalloy in terms of phase volume fraction, by mass percentage, comprises: Al: 3.5-4.5%, Ni: 25.0-30.0%, Mo: 3.0-3.5%, Ta: 5.5-6.5%, Ti: 3.0-3.5%, W: 5.5-6.5%, with the balance being Co and unavoidable impurities, and the sum of the mass percentages of the above components is 100%.

2. A high-γ... A method for preparing cobalt-nickel-based superalloys with varying phase volume fractions, characterized in that, In S4, after successful arc ignition, the arc gun is raised to 15cm, the arc current is increased to 100A, and the arc gun is rotated clockwise at a speed of 5.0° / s. While increasing the arc current to 200A, turn on the magnetic stirring device and set the magnetic stirring current to 5A; Increase the arc current to 500A and the melting time to no less than 1 minute.

3. A high-γ... A method for preparing cobalt-nickel-based superalloys with varying phase volume fractions, characterized in that, In S4, to ensure uniform mixing of components, the sample needs to be flipped over and melted again after each melting process, and then cooled to obtain an alloy ingot. After one melting cycle, the sample is flipped over using a pusher and melted again. Each sample needs to be melted 4 times. After melting, wait for the alloy ingot to cool down to room temperature, open the gas filling valve, and open the furnace door after the gas pressure in the furnace chamber returns to atmospheric pressure.

4. A high-γ method according to claim 1 A method for preparing cobalt-nickel-based superalloys with varying phase volume fractions, characterized in that, In S5, the solution treatment temperature is 1250℃, the time is 10h, the heating rate is 10℃ / min, the holding time is 10h, and the cooling method is air cooling.

5. A high-γ method according to claim 1 A method for preparing cobalt-nickel-based superalloys with varying phase volume fractions, characterized in that, In S5, the aging treatment temperature is 900℃ and the time is 100h.

Images