Preparation method and application of high-performance isotropic GH4698 drum piece

Abstract

The invention belongs to the technical field of powder metallurgy, and relates to a preparation method and application of a high-performance isotropic GH4698 drum piece, prepared GH4698 high-temperature alloy powder with the particle size of 53-250 microns is loaded into a prefabricated sheath under the condition that the vacuum degree is smaller than or equal to 1 * 10 <-3 > Pa, after treatment is conducted 2-3 times through a multi-cycle hot isostatic pressing process system, furnace cooling is conducted, and the high-performance isotropic GH4698 drum piece is obtained. And machining is adopted to remove the sheath to obtain a GH4698 drum piece blank in a powder metallurgy state, and a solid solution and aging heat treatment process is adopted for the drum piece blank, so that the high-performance isotropic GH4698 drum piece can be obtained. According to the preparation method, the yield of the GH4698 drum part can be effectively increased, the GH4698 drum part with high performance and isotropic performance can be obtained by effectively improving the grain size and distribution of the part, the carbide distribution and the internal stress state of the part, the utilization rate of an alloy material is promoted to be increased, the stability of the production process is improved, and in addition, the yield of the GH4698 drum part is improved. All mechanical properties of the prepared GH4698 drum piece meet the performance requirements of a drum shaft for a novel aero-engine.

Description

Technical Field

[0001] The invention belongs to the technical field of powder metallurgy and relates to a preparation method and application of a high-performance isotropic GH4698 drum component. Background Art

[0002] GH4698 is a Ni-Cr based precipitation hardening alloy with a service temperature of 750-800°C. This alloy is based on GH4033, with increased aluminum and titanium content, added niobium and molybdenum, and reduced chromium content. After heat treatment, the alloy microstructure consists of γ matrix, γ', carbides (MC, M 23 C6) and boride. The alloy has excellent comprehensive mechanical properties and long-term organizational stability in the range of 550-800℃, and is suitable for making long-life load-bearing parts such as turbine disks, drum shafts and compressor disks of aircraft engines.

[0003] At present, the manufacturing process of GH4698 drum parts adopts vacuum induction melting + vacuum consumable remelting (or electroslag remelting) process to prepare rods, and then the rods are forged dozens of times to form forging blanks. Then the forging blanks are machined to form drum parts. Under this process condition, the material utilization rate of the blank is extremely low (about 15-20%). In addition, during the forging process, the transverse and longitudinal strain fields, temperature fields and stress fields of the bars are unevenly distributed, resulting in longitudinal and transverse microstructure differences and internal stress differences in the forgings, which in turn leads to longitudinal and transverse mechanical property differences. In addition, the high density of defects such as dislocations in the forging blanks leads to obvious growth tendency and abnormal grain growth during the subsequent heat treatment process. After heat treatment, the grain size of the forged rods is usually 0-2. However, the new generation of aircraft engine drum shaft parts require a grain size of 2-6 for the comprehensive consideration of room temperature strength and plasticity, high temperature durability and other properties. New models of aircraft engine drum shaft parts need to meet higher mechanical performance index requirements, which provides new opportunities for the research and development of new processes. The extremely low material utilization rate and directional discreteness of mechanical properties of forged GH4698 drum parts lead to long production cycles and extremely poor performance stability of drum parts, which seriously affect the installation and test progress of modern aircraft engines.

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

[0005] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, propose a preparation method and application of a high-performance isotropic GH4698 drum member, solve the problems of low material utilization, directional differences in microstructure and mechanical properties in the existing forged GH4698 drum member forming process, and promote the improvement of alloy material utilization and production process stability.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] On the one hand, the present invention provides a method for preparing a high-performance isotropic GH4698 drum element, comprising the following steps:

[0008] Step 1: Prepare GH4698 high temperature alloy powder using GH4698 alloy rod as raw material;

[0009] Step 2: Put the GH4698 high temperature alloy powder prepared in step 1 into a prefabricated package under medium temperature and vacuum conditions, and perform degassing and sealing welding treatment;

[0010] Step 3: subjecting the entire package after degassing and sealing in step 2 to cyclic hot isostatic pressing under the conditions of high temperature and normal pressure + high temperature and high pressure;

[0011] Step 4: Machining to remove the jacket to obtain a powder metallurgy GH4698 drum blank;

[0012] Step 5: subjecting the GH4698 drum blank obtained in step 4 to solid solution + aging heat treatment to obtain a GH4698 drum blank.

[0013] Furthermore, in step 1, the GH4698 high temperature alloy powder is prepared by plasma rotating electrode or argon atomization method.

[0014] Preferably, the GH4698 high-temperature alloy powder is a high-temperature alloy GH4698 powder having a particle size range of 53 to 250 μm obtained after screening, electrostatic and magnetic separation and impurity removal treatment.

[0015] Furthermore, at a medium temperature of 450±10°C and a vacuum degree of ≤1×10 -3 Pa, the GH4698 high-temperature alloy powder prepared in step 1 is loaded into a prefabricated sleeve. During the powder loading process, the prefabricated sleeve is subjected to heating and vibration degassing treatment with a vibration frequency of 25 Hz and an amplitude of 1 mm. After the vibration degassing treatment is completed, a sealing treatment is performed to form a closed space in the prefabricated sleeve containing the GH4698 high-temperature alloy powder.

[0016] Furthermore, in step 3, the cyclic hot isostatic pressing treatment consists of a high temperature and normal pressure stage and a high temperature and high pressure stage. The high temperature and normal pressure stage is performed first, and then the high temperature and high pressure stage is performed, and this cycle is repeated 2 to 3 times, and then the furnace is cooled to 150°C; the specific parameters of the high temperature and normal pressure stage are: temperature: 1190 to 1250°C, pressure: 0.49 to 0.51 MPa, and time: 2 to 4 hours; the specific parameters of the high temperature and high pressure stage are: temperature: 1190 to 1250°C, pressure: 150 to 200 MPa, and time: 2 to 4 hours.

[0017] Furthermore, in step 4, the density of the GH4698 drum blank is greater than 99.9%.

[0018] Furthermore, in step 5, the specific process of the solution + aging heat treatment is: first, keep warm at 1100-1150°C for 8 hours and then air cool, then, keep warm at 1000±10°C for 4 hours and then air cool, and finally, keep warm at 775±10°C for 16 hours and then air cool.

[0019] Furthermore, the room temperature tensile strength of the GH4698 drum member in the longitudinal and transverse directions is greater than 1300 MPa, the yield strength is greater than 880 MPa, the elongation is greater than 20%, the cross-sectional shrinkage is greater than 20%, and the room temperature impact energy KU2 is greater than 50 J.

[0020] On the other hand, the present invention also provides a drum shaft for an aircraft engine, wherein the drum shaft is prepared based on a preparation method of a high-performance isotropic GH4698 drum component.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention first prepares GH4698 high-temperature alloy powder with a particle size range of 53 to 250 μm, and then loads the GH4698 high-temperature alloy powder into a prefabricated sleeve under medium temperature and vacuum conditions, and the sleeve is vibrated and degassed during the powder loading process; the sleeve is subjected to a multi-cycle hot isostatic pressing treatment under preset process parameters; the sleeve is removed by machining, and the powder metallurgy product is subjected to a solid solution + aging heat treatment to obtain a high-performance and isotropic GH4698 drum component. The above method is simple and effective.

[0023] (2) The preparation method provided by the present invention can effectively solve the problems of low material utilization rate, directional differences in microstructure and mechanical properties in the existing forging process of GH4698 drum parts, and promote the improvement of alloy material utilization rate and the stability of the production process. In the prior art, the forging process route is to first prepare the forged rod and then take out the drum shaft parts from it. The material utilization rate is extremely low (about 15-20%). However, by adopting the preparation method of the present invention, only the necessary flaw detection blind area (about 2-3mm) needs to be reserved, and the material utilization rate from alloy powder to the final part can reach more than 90%.

[0024] (3) The preparation method of the present invention adopts a multi-cycle hot isostatic pressing process, which can effectively control the grain size, microstructure and improve the internal stress distribution of the workpiece, effectively improve the grain growth tendency during the heat treatment of the forging and avoid the problem of abnormal grain growth. More importantly, based on the multi-cycle hot isostatic pressing treatment, the uneven distribution of strain field, temperature field and stress field in the forging process of GH4698 drum parts and the directional discreteness of the mechanical properties of the workpiece in the prior art are solved.

[0025] (4) The traditional hot isostatic pressing process only performs hot isostatic pressing for 2 to 4 hours under high temperature and high pressure, and the grain size of the product is often between 6 and 8, which is difficult to meet the high temperature durability performance requirements of the product. Through the high temperature and normal pressure stage of the present invention, the grains inside the powder particles merge and grow under the drive of the decrease of grain boundary energy, increasing the grain size. After the first hot isostatic pressing process is completed and during the cooling process, twin boundaries, subgrain boundaries and dislocations are formed inside the grains under the influence of γ-prime precipitation and metal shrinkage. These surface defects and line defects can serve as rapid diffusion channels for alloy elements during the next cycle of high temperature and normal pressure treatment, promote grain boundary migration and promote grain growth. After multiple cycles of high temperature and normal pressure and high temperature and high pressure hot isostatic pressing processes, the grain size can be effectively controlled to reach 2 to 6 levels, and the high temperature durability of the alloy can be improved. The GH4698 drum parts prepared by the present invention have excellent high temperature durability under the conditions of 750℃ / 412MPa, and the durability life exceeds 150h. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the present invention.

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0028] Figure 1 A flow chart of a method for preparing a high-performance isotropic GH4698 drum member provided by the present invention;

[0029] Figure 2 A schematic diagram of a multi-cycle hot isostatic pressing system in the method for preparing a high-performance isotropic GH4698 drum member provided by the present invention;

[0030] Figure 3 The microstructure diagram of the GH4698 drum component obtained by the technical solution provided by the present invention;

[0031] Figure 4 The microstructure diagram of the drum obtained by using the existing forging technology;

[0032] Figure 5 Transverse carbide distribution diagram of GH4698 drum parts obtained by the technical solution provided by the present invention;

[0033] Figure 6 This is the transverse carbide distribution diagram of the drum obtained by using the existing forging technology;

[0034] Figure 7 The longitudinal carbide distribution diagram of the GH4698 drum obtained by the technical solution provided by the present invention;

[0035] Figure 8 This is the longitudinal carbide distribution diagram of the drum obtained using the existing forging technology. DETAILED DESCRIPTION

[0036] Here, exemplary embodiments will be described in detail, and the embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples of devices consistent with some aspects of the present invention as detailed in the appended claims.

[0037] A method for preparing a high-performance isotropic GH4698 drum component, such as Figure 1 As shown, the specific steps include:

[0038] Step 1: Prepare GH4698 high temperature alloy powder using GH4698 alloy rod as raw material.

[0039] Specifically, the GH4698 high-temperature alloy powder is prepared by a plasma rotating electrode or an argon atomization method. The GH4698 high-temperature alloy powder is a high-temperature alloy GH4698 powder having a particle size range of 53 to 250 μm obtained after screening, electrostatic and magnetic separation and impurity removal treatment.

[0040] Step 2: Under medium temperature and vacuum conditions, the GH4698 high temperature alloy powder prepared in step 1 is placed into a prefabricated package and subjected to degassing and sealing treatment.

[0041] Specifically, at a medium temperature of 450±10°C and a vacuum degree of ≤1×10 -3 Pa, the GH4698 high-temperature alloy powder prepared in step 1 is loaded into a prefabricated sleeve. During the powder loading process, the prefabricated sleeve is subjected to heating and vibration degassing treatment with a vibration frequency of 25 Hz and an amplitude of 1 mm. After the vibration degassing treatment is completed, a sealing treatment is performed to form a closed space in the prefabricated sleeve containing the GH4698 high-temperature alloy powder.

[0042] Step 3: The entire package after degassing and sealing in step 2 is subjected to cyclic hot isostatic pressing treatment under the conditions of high temperature and normal pressure + high temperature and high pressure.

[0043] Specifically, the cyclic hot isostatic pressing treatment consists of a high temperature and normal pressure stage and a high temperature and high pressure stage. The high temperature and normal pressure stage is carried out first, and then the high temperature and high pressure stage is carried out again and again. After 2 to 3 cycles, after the cyclic hot isostatic pressing treatment is completed, the temperature is cooled to 150°C in the furnace. The specific parameters of the high temperature and normal pressure stage are set as follows: temperature: 1190 to 1250°C, pressure: 0.49 to 0.51 MPa, time: 2 to 4 hours; the specific parameters of the high temperature and high pressure stage are set as follows: temperature: 1190 to 1250°C, pressure: 150 to 200 MPa, time: 2 to 4 hours.

[0044] Step 4: Machining to remove the sleeve to obtain the GH4698 drum blank in the powder metallurgy state.

[0045] Specifically, after the above steps 1-3, the GH4698 drum blank is machined to remove the jacket, and the density is >99.9%.

[0046] Step 5: subjecting the GH4698 drum blank obtained in step 4 to solid solution + aging heat treatment to obtain a GH4698 drum blank.

[0047] Specifically, the specific process of the solution + aging heat treatment is: first, keep at 1100-1150°C for 8 hours and then air cool, then keep at 1000±10°C for 4 hours and then air cool, and finally keep at 775±10°C for 16 hours and then air cool. The air cooling is to cool to room temperature by air cooling.

[0048] Furthermore, the room temperature tensile strength of the GH4698 drum member in the longitudinal and transverse directions is greater than 1300 MPa, the yield strength is greater than 880 MPa, the elongation is greater than 20%, the cross-sectional shrinkage is greater than 20%, and the room temperature impact energy KU2 is greater than 50 J.

[0049] In addition, the preparation method of the high-performance isotropic GH4698 drum component of the present invention can be used to prepare drum shafts for aircraft engines, and the mechanical properties of the prepared drum shafts can meet the performance requirements of drum shafts for new aircraft engines.

[0050] The principle of the preparation method of the high-performance isotropic GH4698 drum parts of the present invention is as follows: through the preparation of GH4698 high-temperature alloy powder, a wide particle size distribution (53-250 μm) powder is used, which can effectively improve the tap density of the powder inside the sheath, laying the foundation for obtaining dense parts; at the same time, the larger size powder (150-250 μm) has a larger grain size, which can provide an initial microstructure basis for the larger grain size; while the smaller size powder (53-150 μm) has a smaller grain size, but the deformation amount is large during the hot isostatic pressing process, and the dislocation density in the grain boundary area after deformation is large, which can subsequently promote the migration of grain boundaries and increase the average grain size.

[0051] The present invention can effectively control the grain size, microstructure and improve the internal stress distribution of the product by setting the multi-cycle hot isostatic pressing process parameters. On the one hand, the powder particles have the characteristics of rapid solidification organization, and there are organizational stress and high-density dislocations inside. Under the action of high temperature and normal pressure, the internal stress of the powder is released and the dislocation is annihilated, which is converted into the driving force for grain boundary migration and promotes the increase of grain size. After the high temperature and high pressure stage, the powder particles are promoted to form metallurgical bonding and residual stress is formed inside the product. In the high temperature and normal pressure cycle again, this type of residual stress can be used as a driving force for grain boundary migration, which promotes the increase of grain size. Under conventional hot isostatic pressing process conditions, due to the limitation of the internal grain size of the powder, powder metallurgy products can only obtain products with a grain size of 6 to 8. Such products have poor performance in high temperature endurance and cannot meet the index requirements. By adopting the multi-cycle hot isostatic pressing process of the present invention, a grain size grade with a coordinated and controllable grain size between 2 and 6 can be obtained, which greatly improves the high temperature endurance of the product. On the other hand, the circumferential compressive stress (150-200 MPa) applied to the workpiece during the hot isostatic pressing process effectively improves the internal stress distribution of the workpiece (while the forging in the prior art has residual tensile stress in the circumferential direction, the present invention applies compressive stress), effectively improves the grain growth tendency during the heat treatment of the forging and avoids the problem of abnormal grain growth, see Figure 3-4 From the microstructure comparison diagram of the GH4698 drum part obtained by the scheme of the present invention and the forged drum part obtained by the prior art, it can be clearly seen that the grains in the microstructure of the drum part prepared by the present invention are finer and more uniform, without abnormal growth, while the grains in the microstructure of the forged drum part prepared by the prior art show abnormal growth behavior.

[0052] Specifically, in the cyclic hot isostatic pressing process of high temperature and normal pressure and high temperature and high pressure provided by the present invention, the high temperature and normal pressure process mainly acts to increase the grain size, while the high temperature and high pressure process mainly acts to improve the stress distribution, provide a driving force for grain growth and promote metallurgical bonding between powder particles. The temperature applied in the high temperature stage (1190-1250°C) is higher than the γ' phase complete solution temperature of 1020°C and lower than the alloy initial melting temperature of 1265°C. Within the temperature range, the diffusion rate of elements inside the alloy powder is increased, which promotes the migration rate of grain boundaries; within the temperature range, the powder can also obtain excellent high temperature plasticity and will not undergo local melting to induce high temperature liquid phase structure, providing a good powder plastic deformation foundation for obtaining dense alloy parts. The circumferential compressive stress (150-200MPa) applied during the high temperature and high pressure process promotes the formation of a compressive stress zone inside the part, converts the circumferential tensile stress in the forging drum part forming process into a compressive stress, and improves the uniaxial tensile mechanical properties of the alloy part (such as room temperature tensile, high temperature tensile, high temperature endurance, etc.).

[0053] like Figure 5-8 As shown, using powder particles as materials, element segregation can be limited to micron-sized particles, and the initial carbides are evenly distributed inside the workpiece. Through the preparation method of the present invention, the migration of grain boundaries can be effectively hindered during the subsequent heat treatment process, which is conducive to adjusting the grain size of the part, and can form a structural feature in which carbides are evenly distributed in the horizontal and vertical directions. However, forging using the existing technology will form a structural feature in which carbides are unevenly distributed in the horizontal and vertical directions.

[0054] In summary, by adopting alloy powder with wide particle size distribution and limiting element segregation within micron-sized alloy powder, under the process conditions of high temperature, normal pressure and high temperature, high pressure and multi-cycle hot isostatic pressing, it is possible to achieve grain size control of the workpiece and promote metallurgical bonding of the alloy powder, while simultaneously improving the distribution of strain field, temperature field and stress field inside the workpiece, and obtain high-performance and isotropic powder GH4698 drum parts, which effectively solves the problems of low material utilization, directional differences in microstructure and mechanical properties of drum parts made of this alloy.

[0055] The preparation method of the present invention can flexibly design a package that matches the actual drum product shape characteristics, and put the powder into the package for near-net forming. This process route only needs to reserve the necessary flaw detection blind area (about 2 to 3 mm), and the material utilization rate from alloy powder to the final product can reach more than 90%.

[0056] In order to verify the beneficial effects of the preparation method of the present invention, the following examples are provided to further illustrate the effects.

[0057] Example 1

[0058] Preparation of an X-shaped drum shaft for a certain type of aircraft engine specifically includes the following steps:

[0059] (1) GH4698 alloy rods were used as raw materials and the argon atomization method was used. After screening, electrostatic and magnetic separation, the high-temperature alloy GH4698 powder with a particle size range of 53 to 250 μm was obtained.

[0060] (2) At an ambient temperature of 440°C and a vacuum degree of 3.5×10 -4 The GH4698 high-temperature alloy powder prepared in step 1 is loaded into a prefabricated sleeve under Pa. During the powder loading process, the prefabricated sleeve is subjected to heating and vibration degassing treatment with a vibration frequency of 25 Hz and an amplitude of 1 mm. After the vibration degassing treatment is completed, a sealing welding treatment is performed to form a closed space in the prefabricated sleeve containing the GH4698 high-temperature alloy powder.

[0061] (3) The entire package after degassing and sealing in step 2 is subjected to cyclic hot isostatic pressing treatment under the conditions of high temperature and normal pressure + high temperature and high pressure, wherein the temperature of the high temperature and normal pressure stage is 1250°C, the pressure is 0.51MPa, and the time is 2h; the temperature of the high temperature and high pressure stage is 1190°C, the pressure is 200MPa, and the time is 4h. The high temperature and normal pressure stage is performed first, and then the high temperature and high pressure stage is performed, and this cycle is repeated for 3 times, and then the package is cooled to 150°C with the furnace.

[0062] (4) The casing is removed by machining to obtain a powder metallurgy GH4698 drum blank. The density of the alloy blank is measured to be 99.98%.

[0063] (5) The GH4698 drum blank obtained in step 4 is subjected to solution + aging heat treatment to obtain the target drum shaft, wherein the process of solution + aging heat treatment is: first, keep it at 1150°C for 8 hours and then air cool it, then keep it at 1000°C for 4 hours and then air cool it, and finally, keep it at 770°C for 16 hours and then air cool it.

[0064] Example 2

[0065] Preparation of a Y-shaped drum shaft for a certain type of aircraft engine specifically includes the following steps:

[0066] (1) Using GH4698 alloy rod as raw material and adopting plasma rotating electrode method, after screening, electrostatic and magnetic separation, high temperature alloy GH4698 powder with a particle size range of 53 to 250 μm was obtained.

[0067] (2) At an ambient temperature of 450°C and a vacuum degree of 5×10 -4The GH4698 high-temperature alloy powder prepared in step 1 is loaded into a prefabricated sleeve under Pa. During the powder loading process, the prefabricated sleeve is subjected to heating and vibration degassing treatment with a vibration frequency of 25 Hz and an amplitude of 1 mm. After the vibration degassing treatment is completed, a sealing welding treatment is performed to form a closed space in the prefabricated sleeve containing the GH4698 high-temperature alloy powder.

[0068] (3) The entire package after degassing and sealing in step 2 is subjected to cyclic hot isostatic pressing treatment under the conditions of high temperature and normal pressure + high temperature and high pressure, wherein the temperature of the high temperature and normal pressure stage is 1190°C, the pressure is 0.49MPa, and the time is 4h; the temperature of the high temperature and high pressure stage is 1250°C, the pressure is 150MPa, and the time is 2h. The high temperature and normal pressure stage is performed first, and then the high temperature and high pressure stage is performed, and this cycle is repeated for 2 times, and then the package is cooled to 150°C in the furnace.

[0069] (4) The casing is removed by machining to obtain a powder metallurgy GH4698 drum blank. The density of the alloy blank is measured to be 99.99%.

[0070] (5) The GH4698 drum blank obtained in step 4 is subjected to solution + aging heat treatment to obtain the target drum shaft, wherein the process of solution + aging heat treatment is: first, keep it at 1100°C for 8 hours and then air cool it, then keep it at 1000°C for 4 hours and then air cool it, and finally, keep it at 775°C for 16 hours and then air cool it.

[0071] Example 3

[0072] Preparation of a Z-type drum shaft for a certain type of aircraft engine specifically includes the following steps:

[0073] (1) Using GH4698 alloy rod as raw material and adopting plasma rotating electrode method, after screening, electrostatic and magnetic separation, high temperature alloy GH4698 powder with a particle size range of 53 to 250 μm was obtained.

[0074] (2) At an ambient temperature of 460°C and a vacuum degree of 7.5×10 -4 The GH4698 high-temperature alloy powder prepared in step 1 is loaded into a prefabricated sleeve under Pa. During the powder loading process, the prefabricated sleeve is subjected to heating and vibration degassing treatment with a vibration frequency of 25 Hz and an amplitude of 1 mm. After the vibration degassing treatment is completed, a sealing welding treatment is performed to form a closed space in the prefabricated sleeve containing the GH4698 high-temperature alloy powder.

[0075] (3) The entire package after degassing and sealing in step 2 is subjected to cyclic hot isostatic pressing treatment under the conditions of high temperature and normal pressure + high temperature and high pressure, wherein the temperature of the high temperature and normal pressure stage is 1220°C, the pressure is 0.50MPa, and the time is 3h; the temperature of the high temperature and high pressure stage is 1220°C, the pressure is 180MPa, and the time is 3h. The high temperature and normal pressure stage is performed first, and then the high temperature and high pressure stage is performed, and this cycle is repeated for 2 times, and then the package is cooled to 150°C in the furnace.

[0076] (4) The casing is removed by machining to obtain a powder metallurgy GH4698 drum blank. The density of the alloy blank is measured to be 99.99%.

[0077] (5) The GH4698 drum blank obtained in step 4 is subjected to solution + aging heat treatment to obtain the target drum shaft, wherein the process of solution + aging heat treatment is: first, keep warm at 1125°C for 8 hours and then air cool, then keep warm at 1000°C for 4 hours and then air cool, and finally, keep warm at 775°C for 16 hours and then air cool.

[0078] The following is a comparison of the room temperature tensile, room temperature impact and 750°C / 412MPa high temperature endurance performance of the X\Y\Z type drum shafts prepared in the above three embodiments of the present invention and the drum shafts prepared by the traditional process, with particular attention paid to the directional problem of the mechanical properties of the parts. The specific test results are shown in Table 1 below:

[0079] Table 1 Performance comparison results of the drum shaft made by the present invention and the drum shaft made by the traditional process

[0080]

[0081] It can be seen from the test results in Table 1 that the mechanical properties of the X\Y\Z type GH4698 drum shaft obtained by the present invention are significantly better than those of the drum shaft prepared by the traditional process. Specifically, the room temperature tensile strength of the X\Y\Z type powder metallurgy GH4698 drum shaft prepared by the method of the present invention is greater than 1300MPa, the yield strength is greater than 880MPa, the elongation is greater than 20%, and the cross-sectional shrinkage is greater than 20%; secondly, the room temperature impact performance KU2 of the workpiece is greater than 55J. Thirdly, the GH4698 drum shaft has excellent high temperature endurance performance under the condition of 750℃ / 412MPa, and the endurance life exceeds 150h.

[0082] More importantly, it can be seen from the above data that the GH4698 drum shaft obtained by the preparation method of the present invention has uniform mechanical properties in all directions and there is no directional difference.

[0083] The above description is only a specific embodiment of the present invention, so that those skilled in the art can 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 can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0084] 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-performance isotropic GH4698 drum component, characterized in that: The steps include: Step 1: Prepare GH4698 high temperature alloy powder using GH4698 alloy rod as raw material; Step 2: Put the GH4698 high temperature alloy powder prepared in step 1 into a prefabricated package under medium temperature and vacuum conditions, and perform degassing and sealing welding treatment; Step 3: subjecting the entire package after degassing and sealing in step 2 to cyclic hot isostatic pressing under the conditions of high temperature and normal pressure + high temperature and high pressure; Step 4: Machining to remove the jacket to obtain the GH4698 drum blank in a powder metallurgy state; Step 5: subjecting the GH4698 drum blank obtained in step 4 to solid solution + aging heat treatment to obtain a GH4698 drum blank.

2. The method for preparing the high-performance isotropic GH4698 drum element according to claim 1, characterized in that: In step 1, the GH4698 high temperature alloy powder is prepared by plasma rotating electrode or argon atomization method.

3. The method for preparing the high-performance isotropic GH4698 drum element according to claim 2, characterized in that: The GH4698 high-temperature alloy powder is a high-temperature alloy GH4698 powder with a particle size range of 53 to 250 μm obtained after screening, electrostatic and magnetic separation and impurity removal treatment.

4. The method for preparing the high-performance isotropic GH4698 drum element according to claim 1, characterized in that: In step 2, at a medium temperature of 450±10°C and a vacuum degree of ≤1×10 -3 Under the condition of Pa, the GH4698 high-temperature alloy powder prepared in step 1 is loaded into a prefabricated sleeve. During the powder loading process, the prefabricated sleeve is subjected to a heating vibration degassing treatment. After the vibration degassing treatment is completed, a sealing welding treatment is performed to form a closed space in the prefabricated sleeve containing the GH4698 high-temperature alloy powder.

5. The method for preparing the high-performance isotropic GH4698 drum element according to claim 1, characterized in that: In step 3, the cyclic hot isostatic pressing treatment consists of a high temperature and normal pressure stage and a high temperature and high pressure stage. The high temperature and normal pressure stage is performed first, and then the high temperature and high pressure stage is performed, and this cycle is repeated 2 to 3 times, and then the furnace is cooled; The specific parameters of the high temperature and normal pressure stage are: temperature: 1190-1250°C, pressure: 0.49-0.51MPa, and time: 2-4h; the specific parameters of the high temperature and high pressure stage are: temperature: 1190-1250°C, pressure: 150-200MPa, and time: 2-4h.

6. The method for preparing the high-performance isotropic GH4698 drum element according to claim 1, characterized in that: In step 4, the density of the GH4698 drum blank is greater than 99.9%.

7. The method for preparing the high-performance isotropic GH4698 drum element according to claim 1, characterized in that: In step 5, the specific process of the solution + aging heat treatment is: first, keep warm at 1100-1150°C for 8 hours and then air cool, then keep warm at 1000±10°C for 4 hours and then air cool, and finally, keep warm at 775±10°C for 16 hours and then air cool.

8. The method for preparing the high-performance isotropic GH4698 drum element according to claim 1, characterized in that: The room temperature tensile strength of the GH4698 drum member in the longitudinal and transverse directions is greater than 1300 MPa, the yield strength is greater than 880 MPa, the elongation is greater than 20%, the cross-sectional shrinkage is greater than 20%, and the room temperature impact energy KU2 is greater than 50 J.

9. A drum shaft for an aircraft engine, characterized in that: The drum shaft is prepared based on the preparation method of the high-performance isotropic GH4698 drum component described in any one of claims 1 to 8.

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