Preparation method of high-strength cellular distribution gamma'phase high-temperature alloy

Abstract

The invention relates to the technical field of high-temperature alloy powder metallurgy, in particular to a preparation method of a high-strength cellular distribution gamma'phase high-temperature alloy, which comprises the following steps: preparing high-temperature alloy powder; the prepared high-temperature alloy powder is loaded into a first sheath, and the first sheath is vacuumized and sealed; carrying out preheating treatment on the first sheath; the high-temperature alloy powder in the first package sleeve is dispersed; opening the first sheath, and transferring the high-temperature alloy powder from the first sheath into a second sheath through a charging bucket under a vacuum condition; performing hot isostatic pressing treatment on the second sheath filled with the powder to obtain a first workpiece; cooling the first workpiece to obtain a second workpiece; removing a second sheath outside the second workpiece to obtain a blank, and performing heat treatment on the blank to obtain a target alloy; the powder metallurgy technology is utilized, the preparation technology is adjusted, a specially-distributed gamma'phase is formed in the alloy, and therefore the tensile strength and the endurance strength of the alloy are improved.

Description

Technical Field

[0001] The invention relates to the technical field of high-temperature alloy powder metallurgy, and in particular to a method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy. Background Art

[0002] In many harsh application scenarios of modern industry, when traditional high-temperature alloys with a given composition cannot meet the service requirements of higher loads, in addition to the alloy composition, the microstructure is also a key factor restricting the mechanical properties of the alloy. At present, the microstructure of conventional cast and forged high-temperature alloys mostly presents columnar or equiaxed crystal forms, which makes the mechanical properties of high-temperature alloys close to the bottleneck. Therefore, how to break through the limitations of the microstructure under the realistic constraints of the given composition and improve the tensile strength and endurance strength of the alloy is a technical problem faced by this field. Summary of the invention

[0003] In view of the shortcomings of the prior art, the present invention proposes a method for preparing a high-strength cellular distributed γ′ phase high-temperature alloy. The powder metallurgy technology is used to adjust the preparation process so that a specially distributed γ′ phase is formed inside the alloy, thereby improving the tensile strength and endurance strength of the alloy.

[0004] To achieve the above object, the present invention adopts the following technical solutions: The present invention provides a method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy, comprising the following steps: Step 1: preparing a high temperature alloy powder, wherein the high temperature alloy powder is a mixture of fine powder and coarse powder; Step 2: putting the prepared high temperature alloy powder into a first package, evacuating the first package and sealing it with welding; Step 3: preheating the first package; Step 4: dispersing the high temperature alloy powder in the first package; Step 5: Open the first package, and transfer the high-temperature alloy powder from the first package to the second package through a material tank under vacuum conditions; Step 6: Perform hot isostatic pressing on the second bag filled with powder to obtain a first product; Step 7: Cooling the first product to obtain a second product; Step 8: removing the second sheath outside the second product to obtain a blank, and performing heat treatment on the blank to obtain a target alloy.

[0005] Specifically, in step 3, the first package is preheated by a vacuum heat treatment furnace, an atmospheric furnace or a salt bath.

[0006] Specifically, in step 3, the temperature of the preheating treatment is 500° C. to 900° C., and the time of the preheating treatment is 5 h to 8 h.

[0007] Specifically, in step 8, the blank is heat treated in a salt bath.

[0008] Specifically, in step 8, the process of heat treating the blank is: first, the molten salt is heated to (1140~1200)±5°C, the molten salt is kept flowing at a speed of 0.9m / s~1.5m / s, and then the blank is immersed in the molten salt for heat treatment. The heat treatment time is 1h~5h, and the heat treatment time starts from 30min~90min after the blank is immersed in the molten salt. After the heat treatment is completed, the blank is taken out for air cooling or wind cooling.

[0009] Specifically, in step 1, the fine powder is an alloy powder with a particle size of ≤45μm, and the coarse powder is an alloy powder with a particle size in the range of 150μm~300μm; the mass proportion of fine powder in the high-temperature alloy powder is 55%~85%, the laser particle size distribution peak of the fine powder particle size appears in 20μm~35μm, and the laser particle size distribution peak of the coarse powder particle size appears in 150μm~200μm.

[0010] Specifically, in step 6, the process of hot isostatic pressing treatment is: first, the temperature is increased to 1000℃~1100℃ at a heating rate of 10℃ / min~20℃ / min, the pressure is increased to 30MPa~50MPa with the temperature, and the temperature is kept at 4h~8h; then the pressure is increased to 120MPa~200MPa, and the temperature is kept at 1h~2.5h; finally, the temperature is increased to 1120℃~1170℃ at a heating rate of 0.6℃ / min~1℃ / min, and the temperature is kept at 10min~30min.

[0011] Specifically, in step 7, the cooling process of the first part is: firstly cooled to 1000°C~1050°C at a cooling rate of 4°C / min~6°C / min, and the pressure is reduced during the cooling process. When the temperature reaches 1070°C~1090°C, the pressure is reduced to 20MPa~40MPa; finally, after 40min~75min, the temperature of the first part is reduced to below 400°C.

[0012] Specifically, the first package is a conical package, and after the first package is sealed and welded, the internal vacuum degree is ≤2.6×10 - 3 Pa.

[0013] Specifically, the vacuum degree in the second package is not higher than the vacuum degree in the first package after sealing and welding.

[0014] Compared with the prior art, the present invention has the following beneficial effects: (1) In step 1 of the present invention, the particle size of the high-temperature alloy powder is achieved by mixing coarse powder and fine powder to achieve a bimodal size distribution of the powder particle size. On the one hand, the loose density during powder filling is increased, providing more "channels" for the formation of cellular structure; on the other hand, the coarse powder particles and the fine powder particles have different deformation amounts during the hot isostatic pressing process. The mixed coarse powder and fine powder can obtain a larger strain at the particle boundary of the high-temperature alloy powder and a smaller strain inside the particles of the high-temperature alloy powder, further ensuring the formation of the cellular structure.

[0015] (2) In step 3 of the present invention, the high-temperature alloy powder is preheated at 500°C to 900°C to allow the interstitial atoms C to fully diffuse to the particle surface of the high-temperature alloy powder. Due to the segregation of C atoms, other alloy atoms hardly undergo long-range diffusion.

[0016] (3) In step 6 of the present invention, the hot isostatic pressing process goes through three stages. In the first stage, the temperature is raised to 1000°C~1100°C at a heating rate of 10°C / min~20°C / min, the pressure is raised to 30MPa~50MPa along with the temperature, and the temperature and pressure are maintained for 4h~8h. In this stage, the high-temperature alloy powder is allowed to reach the diffusion temperature first, and only a small stress is applied. In this case, the alloy atoms in the high-temperature alloy powder can undergo sufficient solid-state diffusion. The reason is that in step 3, the C atoms have been enriched on the particle surface of the high-temperature alloy powder. Ti, Nb, and Ta are all strong carbide-forming elements, and Ti, Nb, and Ta atoms are prone to co-segregation with C atoms. Therefore, in this stage, Ti, Nb, and Ta atoms will quickly diffuse to the surface of the high-temperature alloy powder particles, increasing the concentration of Ti, Nb, and Ta elements on the surface of the high-temperature alloy powder particles. In the second stage, the pressure is increased to 120MPa~200MPa, and the temperature and pressure are maintained for 1h~2.5h to cause solid-solid diffusion metallurgical bonding between the particles of the high-temperature alloy powder, so that the high-concentration Ti, Nb, and Ta elements are further The first step is retained at the particle boundary of the high-temperature alloy powder; the third stage is heated to 1120℃~1170℃ at a heating rate of 0.6℃ / min~1℃ / min. This stage is to further compact the alloy, dissolve the γ′ phase, effectively eliminate the original particle boundary of the high-temperature alloy powder, and prevent grain growth. When the high concentration of Ti, Nb, and Ta three γ′ phase-forming elements are concentrated at the particle boundary of the high-temperature alloy powder, a γ′ phase-forming element depletion zone is formed inside the particles of the high-temperature alloy powder, which ensures the formation of cellular structure in the subsequent heat treatment; the third step is to heat up the temperature to 1120℃~1170℃ at a heating rate of 0.6℃ / min~1℃ / min. This stage is to further compact the alloy, dissolve the γ′ phase, effectively eliminate the original particle boundary of the high-temperature alloy powder, and prevent grain growth. In step 7, the cooling process of the first part is: firstly cool to 1000°C~1050°C at a cooling rate of 4°C / min~6°C / min, and reduce the pressure during the cooling process. When the temperature reaches 1070°C~1090°C, the pressure is reduced to 20MPa~40MPa; finally, after 40min~75min, the temperature of the first part is reduced to below 400°C. Due to the difference in the concentration of γ′ phase-forming elements, large-sized γ′ phases will precipitate at the particle boundaries of the high-temperature alloy powder when slowly cooled above 1000~1050°C.

[0017] (4) In step 8 of the present invention, the billet is heat treated by a salt bath, and the heat treatment temperature can be precisely controlled. During the heat treatment process, the molten salt is heated to (1140~1200)±5℃, and the molten salt is kept flowing at a speed of 0.9m / s~1.5m / s. This flow speed can ensure that the billet is heated evenly. The heat treatment time starts from 30min~90min after the billet is immersed in the molten salt. Since the billet is kept warm for 1h~5h in the range of (1140~1200)±5℃, the large-sized γ′ phase precipitated at the boundary of the high-temperature alloy powder particles in step 7 will not be completely dissolved, but the small-sized γ′ phase inside the high-temperature alloy powder particles will be completely dissolved. At the same time, this temperature range will activate the long-range diffusion of alloy atoms, so that the remaining Ti, Nb, and Ta atoms inside the high-temperature alloy powder particles will further diffuse uphill under the traction of the C atoms on the surface of the high-temperature alloy powder particles, forming a high-temperature alloy powder particle. A wide positive concentration gradient of Ti, Nb and Ta elements from the surface to the inside; after the billet is taken out of the salt bath, air cooling or wind cooling with a medium cooling rate is used to precipitate the γ′ phase at the position where the high concentration of Ti, Nb and Ta elements are located near the surface of the high-temperature alloy powder particles, and the precipitated γ′ phase grows during the cooling process; and due to the low concentration of Ti, Nb and Ta elements inside the high-temperature alloy powder particles, a small-sized γ′ phase is precipitated; compared with the organization of step 6, after the heat treatment of step 8, the γ′ phase "channel" between the high-temperature alloy powder particles is widened to form a special cellular organization, and the large-sized γ′ phase between the high-temperature alloy powder particles and the small-sized γ′ phase inside the high-temperature alloy powder particles work synergistically: among them, the large-sized network-distributed γ′ phase enhances the antiphase domain boundary shear stress, and the small-sized γ′ phase distributed in the cellular form forms an extended stacking fault to hinder the dislocation movement, thereby reducing the creep rate, thereby improving the tensile strength and endurance strength of the alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a microstructure photograph of the high-temperature alloy obtained in Example 1 of the present invention; Figure 2 This is a microstructure photograph of the high-temperature alloy obtained in Comparative Example 1; Figure 3 This is a microstructure photograph of the high-temperature alloy obtained in Comparative Example 2; Figure 4 This is a microstructure photograph of the high-temperature alloy obtained in Example 3 of the present invention; Figure 5 This is a microstructure photograph of the high-temperature alloy obtained in Comparative Example 3. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example 1

[0020] This embodiment provides a method for preparing a high-strength cellular distribution γ′ phase FGH4095 high-temperature alloy, comprising the following steps: Step 1: FGH4095 high temperature alloy powder is prepared by plasma rotating electrode method. The process of preparing FGH4095 high temperature alloy powder is as follows: firstly, fine powder is prepared, which is FGH4095 alloy powder with a particle size of ≤45μm, and then coarse powder is prepared, which is FGH4095 alloy powder with a particle size in the range of 150μm~300μm, and the fine powder and coarse powder are mixed to form FGH4095 high temperature alloy powder; in the FGH4095 high temperature alloy powder, the mass proportion of fine powder is 65%, the mass proportion of coarse powder is 35%, and the laser particle size distribution peak of the particle size of FGH4095 high temperature alloy powder appears at 20μm and 150μm; Step 2: Put the FGH4095 high temperature alloy powder into the first package, evacuate the first package and seal it. After sealing, the vacuum degree inside the first package is 2.4×10 -3 Pa, the first sleeve is a conical stainless steel sleeve with a powder outlet at the end; Step 3: placing the sealed first package in a vacuum heat treatment furnace, and preheating the first package at 500° C. for 8 hours; Step 4: After taking the first package out of the vacuum heat treatment furnace, place it on a high-frequency vibration platform to redisperse the preheated FGH4095 high-temperature alloy powder; Step 5: Remove the first package from the high-frequency vibration platform, open the powder outlet of the first package by cutting, and -3 Under the vacuum condition of 1.5×10 -3 Under a vacuum condition of 1.3 Pa, the FGH4095 high temperature alloy powder in the material tank is loaded into a second package, wherein the second package is annular; Step 6: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product; the specific process of the hot isostatic pressing treatment is: firstly heating the temperature to 1020°C at a heating rate of 10°C / min, the pressure increases to 30MPa with the temperature, and the temperature is kept at 4h; then quickly pressurizing to 120MPa, the temperature is kept at 1020°C, and the temperature is kept at 1h; finally, heating the temperature to 1120°C at a heating rate of 0.8°C / min, the pressure is kept at 120MPa, and the temperature is kept at 10min; Step 7: The first product is cooled along with the hot isostatic pressing device, first cooled from 1120°C to 1000°C at a cooling rate of 5°C / min, and when the temperature reaches 1080°C, the pressure is reduced to 20MPa; finally, after 44.6 minutes, the temperature of the first product is reduced to 350°C to obtain the second product; Step 8: After taking the second workpiece out of the hot isostatic pressing device, remove the second sleeve to obtain a blank, and perform salt bath heat treatment on the blank. The specific process of the salt bath heat treatment is: first heat the molten salt to 1140±5°C, keep the molten salt flowing at a speed of 0.9m / s, and then immerse the blank in the molten salt for 1h of salt bath heat treatment. The heat treatment time starts from 42min after the blank is immersed in the molten salt. After the salt bath heat treatment is completed, the blank is taken out of the salt bath and air-cooled to obtain FGH4095 high temperature alloy. Example 2

[0021] This embodiment provides a method for preparing a high-strength cellular distribution γ′ phase FGH4095 high-temperature alloy, comprising the following steps: Step 1: FGH4095 high temperature alloy powder is prepared by plasma rotating electrode method. The process of preparing FGH4095 high temperature alloy powder is as follows: firstly, fine powder is prepared, which is FGH4095 alloy powder with a particle size of ≤45μm, and then coarse powder is prepared, which is FGH4095 alloy powder with a particle size in the range of 150μm~300μm. The fine powder and the coarse powder are mixed to form FGH4095 high temperature alloy powder. In the FGH4095 high temperature alloy powder, the mass proportion of fine powder is 68%, and the mass proportion of coarse powder is 32%. The laser particle size distribution peaks of the particle size of FGH4095 high temperature alloy powder appear at 25μm and 170μm. Step 2: Put the FGH4095 high temperature alloy powder into the first package, evacuate the first package and seal it. After sealing, the vacuum degree inside the first package is 2.0×10 -3 Pa, the first sleeve is a conical stainless steel sleeve with a powder outlet at the end; Step 3: placing the sealed first package in a vacuum heat treatment furnace, and preheating the first package at 600° C. for 7 hours; Step 4: After taking the first package out of the vacuum heat treatment furnace, place it on a high-frequency vibration platform to redisperse the preheated FGH4095 high-temperature alloy powder; Step 5: Remove the first package from the high-frequency vibration platform, open the powder outlet of the first package by cutting, and -3 Under the vacuum condition of 1.6×10 -3 Under a vacuum condition of 1.5 Pa, the FGH4095 high temperature alloy powder in the material tank is loaded into a second package, wherein the second package is cylindrical; Step 6: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product; the specific process of the hot isostatic pressing treatment is: firstly heating the temperature to 1050°C at a heating rate of 15°C / min, the pressure is increased to 37MPa with the temperature, and the temperature is kept at 6h; then quickly pressurizing to 150MPa, the temperature is maintained at 1050°C, and the temperature is kept at 1.5h; finally, heating the temperature to 1140°C at a heating rate of 0.6°C / min, the pressure is maintained at 150MPa, and the temperature is kept at 150MPa for 15min; Step 7: The first product is cooled along with the hot isostatic pressing device, first cooled from 1140°C to 1020°C at a cooling rate of 5°C / min, and when the temperature reaches 1085°C, the pressure is reduced to 25MPa; finally, after 55 minutes, the temperature of the first product is reduced to 380°C to obtain the second product; Step 8: After taking the second workpiece out of the hot isostatic pressing device, remove the second sleeve to obtain a blank, and perform salt bath heat treatment on the blank. The specific process of the salt bath heat treatment is: first heat the molten salt to 1160±5°C, keep the molten salt flowing at a speed of 1.0m / s, and then immerse the blank in the molten salt for 2h of salt bath heat treatment. The heat treatment time starts from 50min after the blank is immersed in the molten salt. After the salt bath heat treatment is completed, the blank is taken out of the salt bath and air-cooled to obtain FGH4095 high temperature alloy. Example 3

[0022] This embodiment provides a method for preparing a high-strength cellular distribution γ′ phase GH4079 high-temperature alloy, comprising the following steps: Step 1: Prepare GH4079 high-temperature alloy powder by plasma rotating electrode method. The process of preparing GH4079 high-temperature alloy powder is as follows: first prepare fine powder, which is GH4079 alloy powder with a particle size of ≤45μm, and then prepare coarse powder, which is GH4079 alloy powder with a particle size in the range of 150μm~300μm, and mix the fine powder with the coarse powder to form GH4079 high-temperature alloy powder; in the GH4079 high-temperature alloy powder, the mass proportion of fine powder is 72%, the mass proportion of coarse powder is 28%, and the laser particle size distribution peak of the particle size of GH4079 high-temperature alloy powder appears at 30μm and 180μm; Step 2: Put GH4079 high temperature alloy powder into the first package, evacuate the first package and seal it. After sealing, the vacuum degree inside the first package is 1.8×10 -3 Pa, the first sleeve is a conical stainless steel sleeve with a powder outlet at the end; Step 3: placing the sealed first package in a vacuum heat treatment furnace, and preheating the first package at 800° C. for 6 hours; Step 4: After taking the first package out of the vacuum heat treatment furnace, place it on a high-frequency vibration platform to redisperse the preheated GH4079 high-temperature alloy powder; Step 5: Remove the first package from the high-frequency vibration platform, open the powder outlet of the first package by cutting, and -3 Under the vacuum condition of 1.3×10 -3 Under a vacuum condition of 1.5 Pa, the GH4079 high temperature alloy powder in the material tank is loaded into a second bag, wherein the second bag is cylindrical; Step 6: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product; the specific process of the hot isostatic pressing treatment is: firstly heating the temperature to 1080°C at a heating rate of 18°C / min, the pressure is increased to 45MPa with the temperature, and the temperature is kept at 45MPa for 7 hours; then quickly pressurizing to 180MPa, maintaining the temperature at 1080°C, and maintaining the temperature at 45MPa for 2 hours; finally, heating the temperature to 1150°C at a heating rate of 0.9°C / min, maintaining the pressure at 180MPa, and maintaining the temperature at 45MPa for 25 minutes; Step 7: The first product is cooled along with the hot isostatic pressing device, first cooled from 1150°C to 1030°C at a cooling rate of 5°C / min, and when the temperature reaches 1070°C, the pressure is reduced to 35MPa; finally, after 65 minutes, the temperature of the first product is reduced to 300°C to obtain the second product; Step 8: After taking the second workpiece out of the hot isostatic pressing device, remove the second sleeve to obtain a blank, and perform salt bath heat treatment on the blank. The specific process of the salt bath heat treatment is: first heat the molten salt to 1180±5°C, keep the molten salt flowing at a speed of 1.2m / s, and then immerse the blank in the molten salt for 3h of salt bath heat treatment. The heat treatment time starts from 70min after the blank is immersed in the molten salt. After the salt bath heat treatment is completed, the blank is taken out of the salt bath and air-cooled to obtain the GH4079 high-temperature alloy. Example 4

[0023] This embodiment provides a method for preparing a high-strength cellular distribution γ′ phase GH4079 high-temperature alloy, comprising the following steps: Step 1: Prepare GH4079 high temperature alloy powder by plasma rotating electrode method. The process of preparing GH4079 high temperature alloy powder is as follows: first prepare fine powder, which is GH4079 alloy powder with a particle size of ≤45μm, and then prepare coarse powder, which is GH4079 alloy powder with a particle size in the range of 150μm~300μm, and mix the fine powder with the coarse powder to form GH4079 high temperature alloy powder; in the GH4079 high temperature alloy powder, the mass proportion of fine powder is 75%, the mass proportion of coarse powder is 25%, and the laser particle size distribution peak of the particle size of GH4079 high temperature alloy powder appears at 35μm and 200μm; Step 2: Put GH4079 high temperature alloy powder into the first package, evacuate the first package and seal it. After sealing, the vacuum degree inside the first package is 1.3×10 -3 Pa, the first sleeve is a conical stainless steel sleeve with a powder outlet at the end; Step 3: placing the sealed first package in a vacuum heat treatment furnace, and preheating the first package at 900° C. for 5 hours; Step 4: After taking the first package out of the vacuum heat treatment furnace, place it on a high-frequency vibration platform to redisperse the preheated GH4079 high-temperature alloy powder; Step 5: Remove the first package from the high-frequency vibration platform, open the powder outlet of the first package by cutting, and -3 Pa vacuum condition, GH4079 superalloy powder was transferred into the material tank through the powder outlet, and then -3 Under a vacuum condition of 1.5 Pa, the GH4079 high temperature alloy powder in the material tank is loaded into a second bag, wherein the second bag is annular; Step 6: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product; the specific process of the hot isostatic pressing treatment is: firstly heating the temperature to 1100°C at a heating rate of 20°C / min, the pressure is increased to 50MPa with the temperature, and the temperature is kept at 50MPa for 8 hours; then quickly pressurizing to 200MPa, maintaining the temperature at 1100°C, and maintaining the temperature at 50MPa for 2.5 hours; finally, heating the temperature to 1170°C at a heating rate of 1°C / min, maintaining the pressure at 200MPa, and maintaining the temperature at 50MPa for 30 minutes; Step 7: The first product is cooled along with the hot isostatic pressing device, first cooled from 1170°C to 1050°C at a cooling rate of 5°C / min, and when the temperature reaches 1090°C, the pressure is reduced to 40MPa; finally, after 75 minutes, the temperature of the first product is reduced to 200°C to obtain the second product; Step 8: After taking the second workpiece out of the hot isostatic pressing device, remove the second sleeve to obtain a blank, and perform salt bath heat treatment on the blank. The specific process of the salt bath heat treatment is: first heat the molten salt to 1200±5°C, keep the molten salt flowing at a speed of 1.5m / s, and then immerse the blank in the molten salt for 5h of salt bath heat treatment. The heat treatment time starts from 90min after the blank is immersed in the molten salt. After the salt bath heat treatment is completed, the blank is taken out of the salt bath and air-cooled to obtain the GH4079 high-temperature alloy.

[0024] In the above embodiments, the lower powder opening of the first package has a diameter of 50-100 mm and a height of 100-200 mm, and the shape of the second package matches the shape of the workpiece.

[0025] Comparative Example 1 This comparative example is a conventional preparation method of FGH4095 high temperature alloy, comprising the following steps: Step 1: FGH4095 high temperature alloy powder with a particle size in the range of 53-150 μm is prepared by a plasma rotating electrode method; Step 2: In 1.5×10 -3 Under the vacuum condition of 1.5×10 -3 Under the vacuum condition of 1.3 Pa, the FGH4095 high temperature alloy powder in the material tank is loaded into the second package, and the second package is annular; Step 3: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product; the specific process of the hot isostatic pressing treatment is: heating to 1120°C at a heating rate of 3°C / min, increasing the pressure to 120MPa as the temperature increases, and maintaining the temperature and pressure for 4 hours; Step 4: The first product is cooled along with the hot isostatic pressing device, and the furnace temperature drops to 350° C. after 1.5 hours to obtain the second product; Step 5: After taking the second part out of the hot isostatic pressing equipment, remove the second jacket to obtain a blank, and heat treat the blank in an atmospheric furnace at a heat treatment temperature of 1155±10°C for 1 hour. After the heat treatment, take out the blank and cool it in a 583°C salt bath to obtain FGH4095 high-temperature alloy.

[0026] Comparative Example 2 This comparative example proposes a method for preparing a FGH4095 high temperature alloy, comprising the following steps: Step 1: FGH4095 high temperature alloy powder is prepared by plasma rotating electrode method. Among the FGH4095 high temperature alloy powder, the mass proportion of fine powder with a particle size of ≤45μm is 95%; Step 2: In 1.5×10 -3 Under the vacuum condition of 1.5×10 -3 Under the vacuum condition of 1.3 Pa, the FGH4095 high temperature alloy powder in the material tank is loaded into the second package, and the second package is annular; Step 3: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product, wherein the specific process of the hot isostatic pressing treatment is: firstly heating the temperature to 1020°C at a heating rate of 10°C / min, increasing the pressure to 120MPa along with the temperature, and maintaining the temperature and pressure for 4h; then heating the temperature to 1120°C at a heating rate of 0.8°C / min, maintaining the pressure at 120MPa, and maintaining the temperature and pressure for 10min; Step 4: The first product is cooled along with the hot isostatic pressing device, and the temperature drops to 350° C. after 1.5 hours to obtain the second product; Step 5: After taking the second workpiece out of the hot isostatic pressing equipment, remove the second sleeve to obtain a blank, and perform salt bath heat treatment on the blank. The specific process of the salt bath heat treatment is as follows: heat the molten salt to 1140±5°C, keep the molten salt flowing at a speed of 0.9m / s, and then immerse the blank in the molten salt for 1h of salt bath heat treatment. The heat treatment time starts from 42min after the blank is immersed in the molten salt. After the salt bath heat treatment is completed, the blank is taken out of the salt bath and air-cooled to obtain FGH4095 high temperature alloy.

[0027] Comparative Example 3 This comparative example proposes a method for preparing a GH4079 high temperature alloy, comprising the following steps: Step 1: Prepare GH4079 high-temperature alloy powder by plasma rotating electrode method. The process of preparing GH4079 high-temperature alloy powder is as follows: first prepare fine powder with a particle size of ≤45μm, then prepare coarse powder with a particle size in the range of 150-300μm, mix the fine powder with the coarse powder to form GH4079 high-temperature alloy powder; in the GH4079 high-temperature alloy powder, the mass proportion of fine powder is 72%, the mass proportion of coarse powder is 28%, and the peak of the laser particle size distribution of the particle size of GH4079 high-temperature alloy powder appears at 30μm and 180μm; Step 2: At 1.3×10 -3 Pa, the GH4079 superalloy powder was transferred into the feed tank and then heated at 1.3×10 -3 Under a vacuum condition of 1.3 Pa, the GH4079 high temperature alloy powder in the material tank is loaded into a second package, wherein the second package is cylindrical; Step 3: placing the second bag filled with powder in a hot isostatic pressing device for hot isostatic pressing treatment to obtain a first product; the specific process of the hot isostatic pressing treatment is: heating to 1150°C at a heating rate of 3°C / min, increasing the pressure to 160MPa as the temperature increases, and maintaining the temperature and pressure for 4 hours; Step 7: The first product is cooled along with the hot isostatic pressing device, first cooled from 1150°C to 1030°C at a cooling rate of 5°C / min, and when the temperature reaches 1070°C, the pressure is reduced to 35MPa; finally, after 65 minutes, the temperature of the first product is reduced to 300°C to obtain the second product; Step 8: After taking the second workpiece out of the hot isostatic pressing device, remove the second sleeve to obtain a blank, and perform salt bath heat treatment on the blank. The specific process of the salt bath heat treatment is: first heat the molten salt to 1180±5°C, keep the molten salt flowing at a speed of 1.2m / s, and then immerse the blank in the molten salt for 3h of salt bath heat treatment. The heat treatment time starts from 70min after the blank is immersed in the molten salt. After the salt bath heat treatment is completed, the blank is taken out of the salt bath and air-cooled to obtain the GH4079 high-temperature alloy.

[0028] The high-temperature alloys prepared in Example 1 and Comparative Examples 1-2 were dissected, and samples were taken from the high-temperature alloy rim (1#), the spoke (2#), the first sampling point (3#) of the hub, and the second sampling point (4#) of the hub. The tensile properties of the samples were tested with reference to GB / T 4338, and the creep properties of the samples were tested with reference to GB / T 2039. Tables 1 and 2 are the test results of the tensile properties and creep properties of the high-temperature alloy obtained in Example 1, respectively. Tables 3 and 4 are the test results of the tensile properties and creep properties of the high-temperature alloy obtained in Comparative Example 1, respectively. Tables 5 and 6 are the test results of the tensile properties and creep properties of the high-temperature alloy obtained in Comparative Example 2, respectively. Table 1 650℃ tensile properties of high temperature alloy obtained in Example 1

[0029] Table 2 Creep properties of high temperature alloy obtained in Example 1

[0030] Table 3 650℃ tensile properties of high temperature alloy obtained in Comparative Example 1

[0031] Table 4 Creep properties of high temperature alloy obtained in Comparative Example 1

[0032] Table 5 650℃ tensile properties of high temperature alloy obtained in Comparative Example 2

[0033] Table 6 Creep properties of high temperature alloy obtained in Comparative Example 2

[0034] It can be seen from Tables 1 to 6 that the tensile properties and creep properties of the high-temperature alloy obtained in Example 1 are better than those of the high-temperature alloys obtained in Comparative Examples 1 to 2. Figures 1 to 3 It can be seen that a cellular γ′ phase structure is formed inside the high-temperature alloy obtained in Example 1, while no cellular γ′ phase structure is formed inside the high-temperature alloys obtained in Comparative Examples 1-2.

[0035] The high-temperature alloys prepared in Example 3 and Comparative Example 3 were dissected, and samples were taken from the first sampling point (A) at the edge of the high-temperature alloy, the second sampling point (B) at the edge of the high-temperature alloy, the first sampling point (C) at the core of the high-temperature alloy, and the second sampling point (D) at the core of the high-temperature alloy. The mechanical properties of the samples were tested, and the tensile properties of the samples were tested with reference to GB / T 228.1, and the endurance properties of the samples were tested with reference to GB / T 4338. Table 7 shows the test results of the mechanical properties of the high-temperature alloy obtained in Example 3, and Table 8 shows the test results of the mechanical properties of the high-temperature alloy obtained in Comparative Example 3: Table 7 Mechanical properties of high temperature alloy obtained in Example 3

[0036] Table 8 Mechanical properties of high temperature alloy obtained in comparative example 3

[0037] It can be seen from Tables 7-8 that the mechanical properties of the high-temperature alloy obtained in Example 3 are better than those of the high-temperature alloy obtained in Comparative Example 3. Figures 4 and 5 It can be seen that a cellular γ′ phase structure is formed inside the high-temperature alloy obtained in Example 3, while a cellular γ′ phase structure is not formed inside the high-temperature alloy obtained in Comparative Example 3.

[0038] The specific embodiments of the present invention enable those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0039] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy, characterized in that: The following steps are involved: Step 1: preparing a high temperature alloy powder, wherein the high temperature alloy powder is a mixture of fine powder and coarse powder; Step 2: putting the prepared high temperature alloy powder into a first package, evacuating the first package and sealing it with welding; Step 3: preheating the first package; Step 4: dispersing the high temperature alloy powder in the first package; Step 5: Open the first package, and transfer the high-temperature alloy powder from the first package to the second package through a material tank under vacuum conditions; Step 6: Perform hot isostatic pressing on the second bag filled with powder to obtain a first product; Step 7: Cooling the first product to obtain a second product; Step 8: removing the second sheath outside the second product to obtain a blank, and performing heat treatment on the blank to obtain a target alloy.

2. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: In step 3, the first package is preheated by a vacuum heat treatment furnace, an atmospheric furnace or a salt bath.

3. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: In step 3, the temperature of the preheating treatment is 500° C. to 900° C., and the time of the preheating treatment is 5 h to 8 h.

4. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: In step 8, the blank is heat treated in a salt bath.

5. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 4, characterized in that: In step 8, the process of heat treating the blank is: first heat the molten salt to (1140~1200)±5°C, keep the molten salt flowing at a speed of 0.9m / s~1.5m / s, and then immerse the blank in the molten salt for heat treatment. The heat treatment time is 1h~5h, and the heat treatment time starts from 30min~90min after the blank is immersed in the molten salt. After the heat treatment is completed, take out the blank and air cool it.

6. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: In step 1, the fine powder is an alloy powder with a particle size of ≤45μm, and the coarse powder is an alloy powder with a particle size in the range of 150μm~300μm; the mass proportion of fine powder in the high-temperature alloy powder is 55%~85%, the laser particle size distribution peak of the fine powder particle size appears in 20μm~35μm, and the laser particle size distribution peak of the coarse powder particle size appears in 150μm~200μm.

7. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: In step 6, the process of hot isostatic pressing treatment is: first, the temperature is increased to 1000°C~1100°C at a heating rate of 10°C / min~20°C / min, the pressure is increased to 30MPa~50MPa with the temperature, and the temperature is kept at 4h~8h; then the pressure is increased to 120MPa~200MPa, and the temperature is kept at 1h~2.5h; finally, the temperature is increased to 1120°C~1170°C at a heating rate of 0.6°C / min~1°C / min, and the temperature is kept at 10min~30min.

8. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 7, characterized in that: In step 7, the cooling process of the first part is: first cool to 1000°C~1050°C at a cooling rate of 4°C / min~6°C / min, and reduce the pressure during the cooling process. When the temperature reaches 1070°C~1090°C, the pressure is reduced to 20MPa~40MPa; finally, after 40min~75min, the temperature of the first part is reduced to below 400°C.

9. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: The first package is a conical package. After the first package is sealed and welded, the internal vacuum degree is ≤2.6×10 -3 Pa.

10. The method for preparing a high-strength cellular distribution γ′ phase high-temperature alloy according to claim 1, characterized in that: The vacuum degree in the second package is not higher than the vacuum degree in the first package after sealing and welding.

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