Powder metallurgy forming method for high-temperature alloy

Abstract

The invention provides a powder metallurgy forming method of a high-temperature alloy. The powder metallurgy forming method comprises the following steps: S1) preparing high-temperature alloy powder; s2) carrying out heat treatment on the high-temperature alloy powder in an Ar-H2 atmosphere; (S3) the high-temperature alloy powder obtained in the step (S2) is subjected to multi-stage hot isostatic pressing treatment; and S4) carrying out solution treatment and aging treatment on the high-temperature alloy obtained in the step S3). According to the powder metallurgy forming method of the high-temperature alloy, a hydrogen-induced cracking mechanism is reversely utilized, the problem of grain boundary weakening / dislocation multiplication is converted into grain boundary strengthening and hydrogen trap design, the problem of hydrogen-induced cracking is avoided from the source, and high reliability and long service life of the high-temperature alloy in a hydrogen-rich environment are achieved.

Description

Technical Field

[0001] This invention relates to the field of high-temperature alloy preparation technology, and in particular to a powder metallurgy forming method for high-temperature alloys. Background Technology

[0002] High-temperature alloys are a class of metallic materials that withstand significant mechanical stress and complex chemical corrosion (such as gas corrosion and oxidation) in high-temperature environments above 600°C. They are developed through alloying (adding elements such as chromium, nickel, cobalt, tungsten, and molybdenum) and precise heat treatment processes, resulting in excellent high-temperature strength, thermal stability, and creep resistance. High-temperature alloys are key basic materials in high-end fields such as aerospace and energy, and are widely used in the manufacture of turbine blades and combustion chambers for aero-engines, as well as core components in ground-based gas turbines and nuclear reactors that require tolerance to extreme high-temperature conditions.

[0003] However, high-temperature alloys are prone to hydrogen-induced embrittlement cracking in hydrogen-rich environments such as aero-engines, significantly reducing component lifespan. Recent research from the University of Texas indicates that hydrogen atom segregation at grain boundaries weakens bonding forces and promotes dislocation slip, leading to localized stress concentration and intergranular crack propagation. Traditional cast alloys, due to their coarse grains, accelerate hydrogen diffusion, while conventional powder metallurgy techniques (such as hot isostatic pressing) struggle to eliminate internal porosity and weak grain boundary structures, leaving residual pores as hydrogen traps. Surface coatings also fail to address the bulk hydrogen embrittlement problem.

[0004] Therefore, there is an urgent need to develop a method for preparing high-strength and high-toughness alloys that inhibits hydrogen-induced cracking from the microstructure source. Summary of the Invention

[0005] The technical problem solved by this invention is to provide a powder metallurgy forming method for high-temperature alloys, which can block the hydrogen-induced cracking path of high-temperature alloys, enabling high-temperature alloys to have high reliability and long service life in hydrogen-rich environments.

[0006] In view of this, this application provides a powder metallurgy forming method for high-temperature alloys, comprising the following steps:

[0007] S1) Prepare high-temperature alloy powder, wherein the composition of the high-temperature alloy powder, by mass percentage, includes: Cr 12.0~18.0%, Co 4.0~8.0%, Mo 3.0~6.0%, W 3.0~6.0%, Al 2.5~4.0%, Ti 2.0~4.5%, Nb 0.5~2.5%, C 0.05~0.15%, B 0.005~0.02%, Ni balance;

[0008] S2) The high-temperature alloy powder is heat-treated in an Ar-H2 atmosphere;

[0009] S3) Perform multi-stage hot isostatic pressing on the high-temperature alloy powder obtained in step S2);

[0010] S4) The high-temperature alloy obtained in step S3) is subjected to solution treatment and aging treatment.

[0011] In some specific embodiments, in step S1), the method for preparing the high-temperature alloy powder is the plasma rotating electrode method, and the particle size of the high-temperature alloy powder is 10~55μm, and the oxygen content is <50ppm.

[0012] In some specific embodiments, in step S2), the volume percentage of H2 in the Ar-H2 atmosphere is 3-5%.

[0013] In some specific embodiments, in step S2), the temperature of the heat treatment is 500~1000℃ and the time of the heat treatment is 1~5h.

[0014] In some specific embodiments, in step S3), the multi-stage hot isostatic pressing (HIP) treatment includes a first-stage HIP treatment and a second-stage HIP treatment. The temperature of the first-stage HIP treatment is 1100~1200℃, the pressure is 100~200MPa, and the time is 1~5h. The temperature of the second-stage HIP treatment is 900~1000℃, the pressure is 80~120MPa, and the time is 1~5h.

[0015] In some specific embodiments, in step S3), a transitional hot isostatic pressing is performed between the first stage hot isostatic pressing treatment and the second hot isostatic pressing treatment. The temperature of the transitional hot isostatic pressing is 1030~1080℃, the pressure is 150~180MPa, and the time is 1~5h.

[0016] In some specific embodiments, in step S3), (Ti,Nb)C nanoparticles with a size of 50~100nm and a density ≥10 are generated in the high-temperature alloy after multi-stage hot isostatic pressing treatment. 15 / m 3 .

[0017] In some specific embodiments, in step S4), the solution treatment temperature is 1100~1200℃, the time is 1~5h, and the cooling method is water quenching.

[0018] In some specific embodiments, in step S4), the aging treatment temperature is 600~800℃ and the time is 5~10h.

[0019] In some specific embodiments, the grain boundary structure of the aging-treated high-temperature alloy is a continuous M-type structure with a thickness of 30-50 nm. 23 The volume percentage of C6 film layers with a grain boundary angle >15° is >80%.

[0020] This application provides a powder metallurgy forming method for high-temperature alloys. First, high-temperature alloy powders containing specific Ti and Nb contents are prepared. Then, the high-temperature alloy powders are heat-treated in an Ar-H2 atmosphere to allow hydrogen atoms to diffuse to the near-surface of the powder, thus exposing potential hydrogen-sensitive regions in advance. Next, the high-temperature alloy powders undergo multi-stage hot isostatic pressing to achieve full densification and refine the grain boundary carbide chains. Finally, solution treatment and aging treatment are used to retain (Ti, Nb)C nanoparticles in the high-temperature alloy, forming a continuous M... 23 The C6 film layer effectively blocks hydrogen permeation. Therefore, the powder metallurgy forming method for high-temperature alloys provided in this application, by introducing nano-hydrogen traps and grain boundary structures, synergistically blocks the hydrogen-induced cracking path. The regulation of the grain boundary orientation difference angle and the formation of continuous carbide chains inhibit hydrogen segregation. The in-situ generated (Ti,Nb)C nanoparticles capture hydrogen and pin dislocations, thereby avoiding the hydrogen-induced cracking problem, ensuring the strength and toughness of the high-temperature alloy, and enabling the high-temperature alloy to have high reliability and long service life in hydrogen-rich environments. Detailed Implementation

[0021] To further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the scope of the claims of the present invention.

[0022] In view of the problem that high-temperature alloys are prone to hydrogen-induced embrittlement cracking in hydrogen-rich environments in the prior art, this application provides a powder metallurgy forming method for high-temperature alloys, which reverses the hydrogen-induced cracking mechanism by transforming the grain boundary weakening / dislocation multiplication problem into grain boundary strengthening + hydrogen trap design, thereby achieving high reliability and long life of high-temperature alloys in hydrogen-rich environments; specifically, the embodiments of this invention disclose a powder metallurgy forming method for high-temperature alloys, including the following steps:

[0023] S1) Prepare high-temperature alloy powder, wherein the composition of the high-temperature alloy powder, by mass percentage, includes: Cr 12.0~18.0%, Co 4.0~8.0%, Mo 3.0~6.0%, W 3.0~6.0%, Al 2.5~4.0%, Ti 2.0~4.5%, Nb 0.5~2.5%, C 0.05~0.15%, B 0.005~0.02%, Ni balance;

[0024] S2) The high-temperature alloy powder is heat-treated in an Ar-H2 atmosphere;

[0025] S3) Perform multi-stage hot isostatic pressing on the high-temperature alloy powder obtained in step S2);

[0026] S4) The high-temperature alloy obtained in step S3) is subjected to solution treatment and aging treatment.

[0027] In the powder metallurgy forming method for high-temperature alloys provided in this application, in step S1, high-temperature alloy powder is prepared. The method for preparing the high-temperature alloy powder is not particularly limited in this application; any method well-known to those skilled in the art can be used. For example, the high-temperature alloy powder can be prepared by a plasma rotating electrode method. The particle size of the high-temperature alloy powder is 10~55μm, and the oxygen content is <50ppm; specifically, the particle size of the high-temperature alloy powder is 15~45μm, and more specifically, the particle size of the high-temperature alloy powder is 20~40μm. The composition of the high-temperature alloy powder, by mass percentage, includes Cr 12.0~18.0%, Co 4.0~8.0%, Mo 3.0~6.0%, W 3.0~6.0%, Al 2.5~4.0%, Ti 2.0~4.5%, Nb 0.5~2.5%, C 0.05~0.15%, B 0.005~0.02%, and Ni as the balance.

[0028] In the high-temperature alloy powder, the Cr content is specifically 13~17%, more specifically, the Cr content is 14~15%; the addition of Cr gives the high-temperature alloy powder oxidation resistance and corrosion resistance. If it is less than 12%, the high-temperature corrosion resistance is insufficient, and if it is more than 18%, excessive σ phase is easily precipitated, leading to brittleness.

[0029] The Co content is specifically 5.0~7.0%; the Co has the function of solid solution strengthening and regulating the dissolution temperature of the γ' phase, but its toughness gain decreases when it exceeds 8.0%.

[0030] The Mo content is specifically 4.0~5.0%; Mo is a strong solid solution reinforcing agent that can significantly improve strength and creep resistance. If the Mo content exceeds 6.0%, it can easily promote the formation of harmful TCP phases (such as μ phase). The W content is specifically 4.0~5.0%; W is also a strong solid solution reinforcing agent that synergistically enhances strength with Mo.

[0031] The Al content is specifically 3.0~3.5%; the Al is a γ' phase forming element (Ni3Al). If its content is less than 2.5%, the amount of γ' phase is insufficient and the strength is low. If its content is higher than 4.0%, the γ' phase is too large and too brittle.

[0032] The Ti content is specifically 3.0~3.5%; the Ti is an auxiliary γ' phase forming element (Ni3Ti), and together with Nb forms the core of MC-type nano hydrogen traps. The Nb content is specifically 1.0~1.5%; the Nb forms a stable (Ti,Nb)C nano hydrogen trap with Ti and C. If its content is less than 0.5%, the hydrogen trap density is insufficient; if it is higher than 2.5%, coarse Laves phase is easily formed, becoming a crack source.

[0033] The C content is specifically 0.10~0.13%; the C is a carbide-forming element used to generate grain boundary M. 23 The content of C6 film and intracrystalline MC nanotrap needs to be matched with the content of Nb and Ti (C / (Nb+Ti) atomic ratio≈0.5).

[0034] The content of B is specifically 0.01~0.015%; as a grain boundary strengthening element, B segregates at the grain boundary to improve the bonding force. If its content is too low, a low melting point eutectic will be formed, which will impair the hot workability.

[0035] In step S2, the high-temperature alloy powder is heat-treated in an Ar-H2 atmosphere to achieve high-temperature alloy pre-alloying treatment. This step introduces a small amount of hydrogen into the near-surface region of the high-temperature alloy powder particles, and the hydrogen atoms will instinctively diffuse to low-energy locations in the high-temperature alloy material - i.e., potential future defects, such as grain boundaries, phase interfaces, and micropores. This process is equivalent to a "hydrogen exposure" or "defect marking". Without this step, the following problems will occur: (1) Loss of the target of "targeted repair": One of the goals of the subsequent multi-stage HIP process is to close the pores. Without the pre-marking of this step, HIP can only repair all pores indiscriminately. After hydrogen pre-exposure, those pores that are most sensitive to hydrogen and most likely to become the origin of hydrogen-induced cracks will be removed. The pores and grain boundaries will be highlighted first, and the subsequent HIP and heat treatment can be more targeted to strengthen and repair these most dangerous defects; (2) It is impossible to achieve true "reverse utilization": The key to this invention is to introduce nano hydrogen defects. The traditional approach is to try to avoid the introduction of hydrogen, while this invention actively introduces trace amounts of hydrogen, exposes the weak points of the material in advance, and strengthens them in subsequent processes. Without this step, the whole scheme reverts to the traditional improvement approach, and there may still be hydrogen-induced cracking problems; (3) The logic chain of performance verification is broken: The excellent hydrogen embrittlement resistance of the final alloy is due to its microstructure being able to effectively suppress hydrogen damage. Without this step, it is difficult to determine that the microstructure of the high-temperature alloy is optimal and designed for hydrogen embrittlement problems.

[0036] In step S2, the volume percentage of H2 in the Ar-H2 atmosphere is 3-5%, specifically, the volume percentage of H2 in the Ar-H2 atmosphere is 4%; the heat treatment temperature is 500-1000℃, and the heat treatment time is 1-5h, specifically, the heat treatment temperature is 600-800℃, and the heat treatment time is 2-3h.

[0037] This application then subjectes the obtained high-temperature alloy powder to multi-stage hot isostatic pressing (HIP), i.e., proceeding to step S3. In this process, the multi-stage HIP includes a first-stage HIP treatment and a second-stage HIP treatment; wherein, the temperature of the first-stage HIP treatment is 1100~1200℃, the pressure is 100~200MPa, and the time is 1~5h, specifically, the temperature of the first-stage HIP treatment is 1120~1160℃, the pressure is 150~180MPa, and the time is 2~4h; the temperature of the second-stage HIP treatment is 900~1000℃, the pressure is 80~120MPa, and the time is 1~5h, specifically, the temperature of the second-stage HIP treatment is 950~980℃, the pressure is 100~110MPa, and the time is 2~4h. The first stage of hot isostatic pressing (HIP) is used to densify the high-temperature alloy, resulting in a relative density > 99.9%. The second stage of HIP is used to drive dislocations with pressure below the γ' phase precipitation temperature, providing a site for the (Ti,Nb)C nanophase to nucleate on the dislocation lines and refine the grain boundary carbide chains.

[0038] Furthermore, a transitional hot isostatic pressing (HIP) is performed between the first stage HIP and the second stage HIP. This transitional HIP is performed at a temperature of 1030–1080°C, a pressure of 150–180 MPa, and a time of 1–5 hours. Specifically, the transitional HIP is performed at a temperature of 1040–1050°C, a pressure of 160–170 MPa, and a time of 2–4 hours. After the transitional HIP, the interior of the high-temperature alloy is pre-filled with stable dislocation structures pinned by nano-traps. When subsequent deformation, such as cold heading, occurs, the newly generated dislocations quickly encounter these pre-existing, pinned dislocation walls or nanoparticles, hindering their movement. Hydrogen atoms cannot rapidly aggregate using the mobile dislocations, significantly reducing the alloy's embrittlement potential.

[0039] After the above-mentioned multi-stage hot isostatic pressing treatment, (Ti,Nb)C nanoparticles with a size of 50~100nm and a density ≥10 are formed in the high-temperature alloy. 15 / m 3 .

[0040] According to the present invention, in step S4, the high-temperature alloy that has undergone hot isostatic pressing is finally subjected to solution treatment and aging treatment. The solution treatment, through temperature and time control, not only dissolves γ' but also ensures that the critical (Ti,Nb)C nano-traps are not completely dissolved. The aging treatment not only precipitates the strengthened γ' phase (size 200nm) but also precisely controls the grain boundary M 23 The morphology (continuous thin film) and thickness (~50 nm) of C6 carbides directly serve grain boundary strengthening, blocking the diffusion path of hydrogen along the grain boundaries. The solution treatment temperature is 1100~1200℃ for 1~5 hours, and the cooling method is water quenching; specifically, the solution treatment temperature is 1120~1180℃ for 2~3 hours. The aging treatment temperature is 600~800℃ for 5~10 hours; specifically, the aging treatment temperature is 630~720℃ for 6~8 hours. Furthermore, the aging treatment can be a two-stage aging treatment: the first-stage aging treatment temperature is 600~700℃ for 1~3 hours, and the second-stage aging treatment temperature is 720~800℃ for 2~7 hours. After aging treatment, a continuous M-shaped thin film with a thickness of 30~50 nm is formed at the grain boundaries of the high-temperature alloy. 23 The volume percentage of C6 film layers with a grain boundary angle >15° is >80%.

[0041] This application provides a powder metallurgy forming method for high-temperature alloys, which reverses the hydrogen-induced cracking mechanism, transforming interface weakening and dislocation propagation problems into grain boundary strengthening and hydrogen trap design, thereby achieving high reliability and long lifespan of the high-temperature alloy in hydrogen-rich environments; the high-temperature alloy prepared in this application has M at the grain boundaries. 23 The C6 enrichment layer can block hydrogen permeation, and the intracrystalline (Ti,Nb)C nanoparticles can detect and capture hydrogen. Experimental results show that in a slow strain rate test (SSRT) in a 1MPa H2 environment, the fracture elongation is increased by 40% (compared to the traditional process); the hydrogen diffusion coefficient is reduced to 1 / 3 of that of conventional alloys (through hydrogen capture by nano (Ti,Nb)C traps), and the tensile strength, yield strength and fracture toughness are greatly improved.

[0042] To further understand the present invention, the powder metallurgy forming method for high-temperature alloys provided by the present invention will be described in detail below with reference to the embodiments. The scope of protection of the present invention is not limited by the following embodiments.

[0043] Example 1: Fabrication of an aero-engine turbine disk

[0044] 1) The following high-temperature alloy powder, Ni-15Cr-5Co-4Mo-4W-3Al-3Ti-1Nb-0.1C-0.01B, was prepared by plasma rotating electrode method. The particle size of this high-temperature alloy powder is 15~45μm and the oxygen content is ≤45ppm.

[0045] 2) The high-temperature alloy was pre-alloyed at 800℃ for 1h in an Ar-4%H2 mixed atmosphere and then slowly cooled to form a hydrogen-sensitive marking region with a depth of 100~200nm in the subsurface layer of the powder.

[0046] 3) The high-temperature alloy powder obtained in step 2) is subjected to two-stage hot isostatic pressing: the first stage of hot isostatic pressing is to achieve full densification (porosity <0.05%), and the second stage of hot isostatic pressing is to apply pressure below the γ' phase precipitation temperature to drive the in-situ generation of (Ti,Nb)C nanoparticles (density 3×10⁻⁶). 15 / m 3 (size 50±10nm); wherein, the temperature of the first stage of hot isostatic pressing is 1120℃, the pressure is 150MPa, and the time is 4h; the temperature of the second stage of hot isostatic pressing is 950℃, the pressure is 100MPa, and the time is 2h.

[0047] 4) The high-temperature alloy obtained in step 3) is first subjected to solution treatment to retain nano-carbides, then subjected to aging treatment, and then machined to finally obtain a high-temperature alloy aero-engine turbine disk; wherein the solution treatment temperature is 1180℃, the holding time is 1h, the cooling method is water quenching, the aging treatment temperature is 720℃, and the holding time is 8h.

[0048] The high-temperature alloy prepared in this embodiment forms a continuous M-shaped structure at the grain boundaries. 23 C6 thin film (thickness 40±5nm) with high-angle grain boundaries (>15°) accounting for 85%.

[0049] Example 2: Manufacturing of high-temperature fasteners for aerospace applications

[0050] 1) The following high-temperature alloy powder, Ni-15Cr-5Co-4Mo-4W-3Al-3Ti-1Nb-0.1C-0.01B, was prepared by plasma rotating electrode method. The particle size of this high-temperature alloy powder is 10~25μm and the oxygen content is ≤45ppm.

[0051] 2) The high-temperature alloy was pre-alloyed at 800℃ for 1h in an Ar-4%H2 mixed atmosphere and then slowly cooled to form a hydrogen-sensitive marking region with a depth of 100~200nm in the subsurface layer of the powder.

[0052] 3) The high-temperature alloy powder obtained in step 2) is subjected to three-stage hot isostatic pressing: the first stage hot isostatic pressing is used to achieve full densification (porosity <0.05%), the transition stage hot isostatic pressing is used to enhance the precipitation of (Ti,Nb)C in the dislocation multiplication zone, and the second stage hot isostatic pressing is used to apply pressure below the γ' phase precipitation temperature to drive the in-situ generation of (Ti,Nb)C nanoparticles (density 3×10⁻⁶). 15 / m 3(size 50±10nm). The first stage of hot isostatic pressing has a temperature of 1120℃, a pressure of 150MPa, and a time of 4h; the transition stage has a temperature of 1050℃, a pressure of 180MPa, and a time of 1h; and the second stage of hot isostatic pressing has a temperature of 950℃, a pressure of 100MPa, and a time of 2h.

[0053] 4) The high-temperature alloy obtained in step 3) is first subjected to solution treatment to retain nano-carbide, and then subjected to two-stage aging treatment to make the grain boundaries M 23 With a C6 coverage of >95%, the high-temperature alloy aerospace fastener was finally obtained by cold heading. The solution treatment temperature was 1180℃, the holding time was 1h, the cooling method was water quenching, and the temperature of the two-stage aging treatment was 700℃×4h+760℃×2h.

[0054] The microstructure of the high-temperature alloy prepared in this embodiment shows the presence of nano-carbide pinned dislocation walls within the deformation zone (TEM verification), which effectively blocks hydrogen-promoted local slip.

[0055] Comparative Example 1

[0056] The preparation method is basically the same as in Example 1, except that step 2 is not performed.

[0057] Comparative Example 2

[0058] The preparation method is basically the same as in Example 1, except that the high-temperature alloy powder is Ni-15Cr-5Co-4Mo-4W-3Al-0.1C-0.01B.

[0059] The high-temperature alloy prepared in this comparative example does not contain (Ti,Nb)C nanoparticles.

[0060] Comparative Example 3

[0061] The preparation method is basically the same as in Example 1, except that the high-temperature alloy is IN718 high-temperature alloy.

[0062] The performance of the high-temperature alloy products prepared in the above embodiments and comparative examples was tested according to existing methods, and the results are shown in Table 1.

[0063] Table 1. Performance data of high-temperature alloys prepared in the examples and comparative examples.

[0064]

[0065] As shown in Table 1, the high-temperature alloy products provided in this application have excellent comprehensive properties.

[0066] The above description of the embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0067] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily 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 invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A powder metallurgy forming method for a high-temperature alloy, comprising the following steps: S1) Prepare high-temperature alloy powder, wherein the composition of the high-temperature alloy powder, by mass percentage, includes: Cr 12.0~18.0%, Co 4.0~8.0%, Mo 3.0~6.0%, W 3.0~6.0%, Al 2.5~4.0%, Ti 2.0~4.5%, Nb 0.5~2.5%, C 0.05~0.15%, B 0.005~0.02%, Ni balance; S2) The high-temperature alloy powder is heat-treated in an Ar-H2 atmosphere; S3) Perform multi-stage hot isostatic pressing on the high-temperature alloy powder obtained in step S2); S4) The high-temperature alloy obtained in step S3) is subjected to solution treatment and aging treatment.

2. The powder metallurgy forming method according to claim 1, characterized in that, In step S1), the method for preparing the high-temperature alloy powder is the plasma rotating electrode method, and the particle size of the high-temperature alloy powder is 10~55μm, and the oxygen content is <50ppm.

3. The powder metallurgy forming method according to claim 1, characterized in that, In step S2), the volume percentage of H2 in the Ar-H2 atmosphere is 3-5%.

4. The powder metallurgy forming method according to claim 1, characterized in that, In step S2), the temperature of the heat treatment is 500~1000℃, and the time of the heat treatment is 1~5h.

5. The powder metallurgy forming method according to claim 1, characterized in that, In step S3), the multi-stage hot isostatic pressing (HIP) treatment includes a first-stage HIP treatment and a second-stage HIP treatment. The temperature of the first-stage HIP treatment is 1100~1200℃, the pressure is 100~200MPa, and the time is 1~5h. The temperature of the second-stage HIP treatment is 900~1000℃, the pressure is 80~120MPa, and the time is 1~5h.

6. The powder metallurgy forming method according to claim 5, characterized in that, In step S3), a transitional hot isostatic pressing is performed between the first stage hot isostatic pressing treatment and the second hot isostatic pressing treatment. The temperature of the transitional hot isostatic pressing is 1030~1080℃, the pressure is 150~180MPa, and the time is 1~5h.

7. The powder metallurgy forming method according to claim 1 or 6, characterized in that, In step S3), (Ti,Nb)C nanoparticles with a size of 50~100nm and a density ≥10 are generated in the high-temperature alloy after multi-stage hot isostatic pressing treatment. 15 / m 3 .

8. The powder metallurgy forming method according to claim 1, characterized in that, In step S4), the solution treatment temperature is 1100~1200℃, the time is 1~5h, and the cooling method is water quenching.

9. The powder metallurgy forming method according to claim 1, characterized in that, In step S4), the aging treatment is carried out at a temperature of 600~800℃ for 5~10h.

10. The powder metallurgy forming method according to claim 1, characterized in that, The grain boundary structure of the aged high-temperature alloy is a continuous M-type structure with a thickness of 30-50 nm. 23 The volume percentage of C6 films with grain boundary angles >15° is >80%.

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