A large-size GH3230 nickel-based alloy special-shaped tube and its preparation method

Abstract

The invention belongs to the technical field of nickel-based alloy material processing and forming, and specifically relates to a large-size GH3230 nickel-based alloy special-shaped tube and a preparation method thereof, comprising preparing raw materials: preparing GH3230 alloy powder, and screening it to obtain GH3230 of a set particle size; adding a strengthening phase: mixing rare earth oxide particles and GH3230 evenly to obtain GH3230 mixed powder; charging: pre-treating the sheath and the core, and then loading the mixed powder into the sheath; hot isostatic pressing treatment: degassing, sealing welding and hot isostatic pressing treatment of the sheath; processing treatment: removing the sheath and the core of the hot isostatic pressing blank to obtain a GH3230 nickel-based alloy special-shaped tube blank, and sequentially heat treating and finishing it to obtain a GH3230 nickel-based alloy special-shaped tube of a target size. The invention overcomes the shortcomings of the traditional technology, such as the complicated forming process, easy cracking of the product, uneven structure, and low raw material utilization.

Description

Technical Field

[0001] The invention belongs to the technical field of nickel-based alloy material processing and forming, and particularly relates to a large-size GH3230 nickel-based alloy special-shaped tube and a preparation method thereof. Background Art

[0002] GH3230 alloy is a Ni-Cr based solid solution strengthened high temperature alloy. It is the main material for manufacturing aircraft engines, gas turbines, and turbine working blades. It has high strength, resistance to cold and hot fatigue, heat corrosion, and oxidation resistance. Its maximum application temperature can reach 1050°C. It has been widely used in the fields of national defense and aerospace.

[0003] With the development of aerospace technology, the structure of the hot end components of aircraft engines has become more complex, and higher requirements have been placed on their high-temperature performance. Traditional forming methods such as casting and welding have made it difficult to manufacture complex components with optimized structures. In recent years, laser powder bed fusion technology (LPBF) has overcome the difficulty of forming complex structural parts, but GH3230 formed by LPBF has cracking defects, which will seriously reduce the performance of the components, which greatly limits its application. Hot isostatic pressing (HIP) treatment is an effective method to eliminate such microcracks. Although HIP treatment can close microcracks and improve the fatigue performance of parts manufactured by LPBF, this treatment does cause excessive grain growth and coarsening. In addition, the additional post-processing costs reduce the economic attractiveness of metal LPBF.

[0004] In addition, traditional precipitation phase strengthening technology will lead to a decrease in the high-temperature strength of the material due to the aggregation and growth of the precipitate phase at high temperature.

[0005] In view of this, the inventor provides a large-size GH3230 nickel-based alloy special-shaped tube and a preparation method thereof to solve the above technical problems. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art, and propose a large-size GH3230 nickel-based alloy special-shaped tube and its preparation method, which realizes the batch preparation of large-size GH3230 nickel-based alloy special-shaped tubes with high performance and low cost by adopting hot isostatic pressing combined with cladding, core and process parameter control, and at the same time, stable nano-scale rare earth oxide particles (Ce02, La203, Y203, etc.) are added to the material matrix for dispersion strengthening, and the dispersed nanoparticles effectively pin dislocations and grain boundaries, thereby improving the high-temperature comprehensive mechanical properties of the GH3230 nickel-based alloy and meeting its use requirements at high temperatures. The present invention solves the problem of difficult shape and property control in the preparation of nickel-based high-temperature alloys by traditional methods.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] In one aspect, the present invention provides a method for preparing a large-size GH3230 nickel-based alloy special-shaped tube, comprising the following steps:

[0009] Step 1, preparing raw materials: preparing GH3230 alloy powder, and sieving the GH3230 alloy powder to obtain GH3230 alloy powder of a set particle size;

[0010] Step 2, adding a strengthening phase: uniformly mixing the rare earth oxide particles and the GH3230 alloy powder of a set particle size obtained in step 1 to obtain a GH3230 mixed powder;

[0011] Step 3, loading: pre-treating the pre-made package and core, and then loading the GH3230 mixed powder obtained in step 2 into the package;

[0012] Step 4, hot isostatic pressing treatment: the bag containing the GH3230 mixed powder is subjected to degassing and sealing welding treatment, and then subjected to hot isostatic pressing treatment to obtain a hot isostatic pressed blank;

[0013] Step 5, processing: removing the sheath and the core of the hot isostatic pressed blank to obtain a GH3230 nickel-based alloy special-shaped tube blank, and sequentially performing heat treatment and finishing treatment on the GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0014] Furthermore, in step 1, a plasma rotating electrode is used to prepare GH3230 alloy powder, and the set particle size of the GH3230 alloy powder after screening is 53 μm to 150 μm.

[0015] Optionally, the set particle size is 53μm to 73μm, 74μm to 93μm, 94μm to 113μm, 114μm to 133μm, or 134μm to 150μm.

[0016] Furthermore, in step 2, the rare earth oxide particles include CeO2, La2O3 or Y2O3, and the particle size of the rare earth oxide particles is 50nm to 100nm.

[0017] Preferably, the rare earth oxide particles are Y2O3, which is a common rare earth oxide with easy availability, high thermal stability and good chemical inertness. By introducing Y2O3 nanoparticles into the alloy matrix, the dispersed Y2O3 nanoparticles are stable at high temperatures and become an effective barrier to prevent dislocation movement, which has an excellent effect on improving the high temperature strength of nickel-based alloys.

[0018] Optionally, the particle size of the rare earth oxide particles is 50nm-60nm, 61nm-70nm, 71nm-80nm, 81nm-90nm, or 91nm-100nm.

[0019] Furthermore, in step 2, the added amount of the rare earth oxide particles is 0.5wt% to 3wt%, and the rare earth oxide particles and GH3230 alloy powder are mixed in a mixer for 10h to 40h.

[0020] Furthermore, in step 3, the sheath is made according to the structure and size of the GH3230 nickel-based alloy special-shaped tube to be prepared, and the sheath is arranged on the outside of the core that is adapted to its structure.

[0021] Furthermore, the specific process of step 3 is as follows:

[0022] Step 3.1, the prefabricated package and core are cleaned and dried in sequence, and then the treated package is placed on the outside of the core;

[0023] Step 3.2: Put the GH3230 mixed powder into a bag on a vibration platform.

[0024] Furthermore, in step 4, when the package is subjected to electron beam sealing welding, the sealing welding current is 50 mA to 90 mA, the welding speed is 140 to 260° / min, and the number of welding times is 2 to 3 times;

[0025] Furthermore, in step 4, during the hot isostatic pressing treatment, the temperature is set to 1170° C. to 1250° C., the time is 2 h to 4 h, and the pressure is 120 MPa to 150 MPa.

[0026] Further, in step 5, the hot isostatic pressed blank obtained in step 4 is machined to remove the jacket and the core;

[0027] The heat treatment includes solution treatment and aging treatment; during the solution treatment, the temperature is set at 1150°C to 1200°C, the time is 2h to 4h, and water cooling is adopted; during the aging treatment, the temperature is set at 870°C to 900°C, the time is 4h to 6h, and air cooling is adopted to room temperature.

[0028] On the other hand, the present invention also provides a large-size GH3230 nickel-based alloy special-shaped tube, which is prepared based on the preparation method as described above, and has the properties of 900°C tensile strength>200Mpa, yield strength>150Mpa, and elongation>10%.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] The invention proposes a method for preparing a large-size GH3230 nickel-based alloy special-shaped tube. The method uses high-purity GH3230 alloy powder with a specific particle size distribution as raw material, and performs hot isostatic pressing on the raw material using a sheath and a core. The process parameters are controlled at the same time to control the size of the GH3230 special-shaped tube, thereby overcoming the shortcomings of the traditional technology, such as complex molding process, easy cracking of the product, uneven structure, and low raw material utilization rate. In addition, stable nano-scale rare earth oxide particles (CeO2, La2O3 or Y2O3, etc.) are added to the raw material matrix through a mechanical alloying process for dispersion strengthening. The dispersed nanoparticles effectively pin dislocations and grain boundaries, thereby improving the high-temperature comprehensive mechanical properties of the GH3230 nickel-based alloy and meeting its use requirements at high temperatures. The preparation method can obtain a large-size GH3230 nickel-based alloy special-shaped tube that meets the requirements of composition, structure, strength and plasticity, and the raw material utilization rate is ≥40%. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] 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.

[0032] 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.

[0033] Figure 1 The present invention is a flow chart of the preparation method. DETAILED DESCRIPTION

[0034] 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 consistent with some aspects of the present invention described in detail in the appended claims.

[0035] On the one hand, see Figure 1 The embodiment of the present invention provides a method for preparing a large-size GH3230 nickel-based alloy special-shaped tube, comprising the following steps:

[0036] Step 1, preparing raw materials: preparing GH3230 alloy powder, and sieving the GH3230 alloy powder to obtain GH3230 alloy powder of a set particle size;

[0037] Step 2, adding a strengthening phase: uniformly mixing the rare earth oxide particles and the GH3230 alloy powder of a set particle size obtained in step 1 to obtain a GH3230 mixed powder;

[0038] Step 3, loading: pre-treating the pre-made package and core, and then loading the GH3230 mixed powder obtained in step 2 into the package;

[0039] Step 4, hot isostatic pressing treatment: the bag containing the GH3230 mixed powder is subjected to degassing and sealing welding treatment, and then subjected to hot isostatic pressing treatment to obtain a hot isostatic pressed blank;

[0040] Step 5, processing: removing the sheath and the core of the hot isostatic pressed blank to obtain a GH3230 nickel-based alloy special-shaped tube blank, and sequentially performing heat treatment and finishing treatment on the GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0041] Furthermore, in step 1, a plasma rotating electrode is used to prepare GH3230 alloy powder, and the set particle size of the GH3230 alloy powder after screening is 53 μm to 150 μm.

[0042] Furthermore, in step 2, the rare earth oxide particles include CeO2, La2O3 or Y2O3, and the particle size of the rare earth oxide particles is 50nm to 100nm.

[0043] Furthermore, in step 2, the addition amount of the rare earth oxide particles is 0.5wt% to 3wt%, and the mixing time of the rare earth oxide particles and the GH3230 alloy powder is 10h to 40h.

[0044] Furthermore, in step 3, the sheath is made according to the structure and size of the GH3230 nickel-based alloy special-shaped tube, and the sheath is arranged on the outside of the core that is adapted to its structure.

[0045] Furthermore, the specific process of step 3 is as follows:

[0046] Step 3.1, the prefabricated package and core are cleaned and dried in sequence, and then the treated package is placed on the outside of the core;

[0047] Step 3.2: Put the GH3230 mixed powder into a bag on a vibration platform.

[0048] Furthermore, in step 4, when the package is subjected to electron beam sealing welding, the sealing welding current is 50 mA to 90 mA, the welding speed is 140 to 260° / min, and the number of welding times is 2 to 3 times;

[0049] Furthermore, in step 4, during the hot isostatic pressing treatment, the temperature is 1170° C. to 1250° C., the time is 2 h to 4 h, and the pressure is 120 MPa to 150 MPa.

[0050] Further, in step 5, the hot isostatic pressed blank obtained in step 4 is machined to remove the jacket and the core;

[0051] The heat treatment includes solution treatment and aging treatment, wherein during the solution treatment, the temperature is 1150°C to 1200°C, the time is 2h to 4h, and water cooling is adopted; during the aging treatment, the temperature is 870°C to 900°C, the time is 4h to 6h, and air cooling is adopted to room temperature.

[0052] On the other hand, the present invention provides a large-size GH3230 nickel-based alloy special-shaped tube, which is prepared based on the preparation method as described above, and has the properties of 900°C tensile strength>200Mpa, yield strength>150Mpa, and elongation>10%.

[0053] Example 1

[0054] Step 1: preparing GH3230 alloy powder by using a plasma rotating electrode, and sieving the prepared GH3230 alloy powder to select GH3230 alloy powder with a particle size range of 53 μm to 150 μm as a raw material;

[0055] Step 2, selecting Y2O3 ceramic particles with a particle size of 50nm to 100nm as the strengthening phase of the GH3230 nickel-based alloy, the addition amount of the Y2O3 ceramic particles is 1wt%, and the GH3230 nickel-based alloy powder and the Y2O3 ceramic particles are mixed in a mixer for 10 hours, and the obtained powder is recorded as GH3230Y;

[0056] Step 3, clean the prefabricated sleeve and core, dry them, then put the sleeve on the outside of the core, further put the GH3230Y alloy powder into the sleeve on the vibration platform, and degas and electron beam seal the sleeve filled with GH3230Y powder, the welding current is 50mA, the welding speed is 140° / min, and the number of welding is 2 times;

[0057] Among them, a corresponding sheath is made according to the specifications of the special-shaped tube to be prepared, and the sheath is set on the outside of the core that is compatible with its structure, and the sheath and the core are both made of steel;

[0058] Step 4, hot isostatic pressing the sealed and welded package to obtain a hot isostatic pressed blank. Specifically, the hot isostatic pressing is performed at a temperature of 1170° C., a time of 4 hours, and a pressure of 150 MPa.

[0059] Step 5: machining the obtained hot isostatic pressed blank to remove the jacket and the steel core, thereby obtaining a GH3230 nickel-based alloy special-shaped tube blank;

[0060] Step 6: sequentially heat-treating and finishing the obtained GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0061] Among them, heat treatment includes solution treatment and aging treatment;

[0062] Specifically, during the solution treatment, the temperature is set to 1150°C, the time is 4 hours, and water cooling is adopted; during the aging treatment, the temperature is set to 870°C, the time is 6 hours, and air cooling is adopted to room temperature; after the heat treatment is completed, the GH3230 nickel-based alloy special-shaped tube blank is finely processed to obtain a GH3230 nickel-based alloy special-shaped tube with a tensile strength of 900°C>200Mpa, a yield strength>150Mpa, and an elongation>10%.

[0063] Example 2

[0064] Step 1: preparing GH3230 alloy powder by using a plasma rotating electrode, and sieving the prepared GH3230 alloy powder to select GH3230 alloy powder with a particle size range of 53 μm to 150 μm as a raw material;

[0065] Step 2, selecting Y2O3 ceramic particles with a particle size of 50nm to 100nm as the strengthening phase of the GH3230 nickel-based alloy, the addition amount of Y2O3 ceramic particles is 1.5wt%, and the GH3230 nickel-based alloy powder and the Y2O3 ceramic particles are mixed in a mixer for 24h, and the obtained powder is recorded as GH3230Y;

[0066] Step 3, clean the prefabricated sleeve and core, dry them, and then put the sleeve on the outside of the core, further put the GH3230Y alloy powder into the sleeve on the vibration platform, and degas and electron beam seal the sleeve filled with GH3230Y powder, the welding current is 70mA, the welding speed is 200° / min, and the number of welding is 3 times;

[0067] Among them, a corresponding sheath is made according to the specifications of the special-shaped tube to be prepared, and the sheath is set on the outside of the core that is compatible with its structure, and the sheath and the core are both made of steel;

[0068] Step 4, hot isostatic pressing the sealed and welded package to obtain a hot isostatic pressed blank. Specifically, the hot isostatic pressing is performed at a temperature of 1200° C., a time of 3 h, and a pressure of 140 MPa.

[0069] Step 5: machining the obtained hot isostatic pressed blank to remove the jacket and the steel core, thereby obtaining a GH3230 nickel-based alloy special-shaped tube blank;

[0070] Step 6: sequentially heat-treating and finishing the obtained GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0071] Among them, heat treatment includes solution treatment and aging treatment;

[0072] Specifically, during the solution treatment, the temperature is set to 1170°C, the time is 3 hours, and water cooling is adopted; during the aging treatment, the temperature is set to 880°C, the time is 5 hours, and air cooling is adopted to room temperature; after the heat treatment is completed, the GH3230 nickel-based alloy special-shaped tube blank is finely processed to obtain a GH3230 nickel-based alloy special-shaped tube with a tensile strength of 900°C>200Mpa, a yield strength>150Mpa, and an elongation>10%.

[0073] Example 3

[0074] Step 1: preparing GH3230 alloy powder by using a plasma rotating electrode, and sieving the prepared GH3230 alloy powder to select GH3230 alloy powder with a particle size range of 53 μm to 150 μm as a raw material;

[0075] Step 2, selecting Y2O3 ceramic particles with a particle size of 50nm to 100nm as the strengthening phase of the GH3230 nickel-based alloy, the addition amount of Y2O3 ceramic particles is 3wt%, and the GH3230 nickel-based alloy powder and the Y2O3 ceramic particles are mixed in a mixer for 40h, and the obtained powder is recorded as GH3230Y;

[0076] Step 3, clean the prefabricated sleeve and core, dry them, and then put the sleeve on the outside of the core, further put the GH3230Y alloy powder into the sleeve on the vibration platform, and degas and electron beam seal the sleeve filled with GH3230Y powder, the welding current is 90mA, the welding speed is 260° / min, and the number of welding times is 3 times;

[0077] Among them, a corresponding sheath is made according to the specifications of the special-shaped tube to be prepared, and the sheath is set on the outside of the core that is compatible with its structure, and the sheath and the core are both made of steel;

[0078] Step 4, hot isostatic pressing the sealed and welded package to obtain a hot isostatic pressed blank. Specifically, the hot isostatic pressing is performed at a temperature of 1250° C., a time of 2 h, and a pressure of 120 MPa.

[0079] Step 5: machining the obtained hot isostatic pressed blank to remove the jacket and the steel core, thereby obtaining a GH3230 nickel-based alloy special-shaped tube blank;

[0080] Step 6: sequentially heat-treating and finishing the obtained GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0081] Among them, heat treatment includes solution treatment and aging treatment;

[0082] Specifically, during the solution treatment, the temperature is set to 1200°C, the time is 2h, and water cooling is adopted; during the aging treatment, the temperature is set to 900°C, the time is 4h, and air cooling is adopted to room temperature; after the heat treatment is completed, the GH3230 nickel-based alloy special-shaped tube blank is finely processed to obtain a GH3230 nickel-based alloy special-shaped tube with a tensile strength of 900°C>200Mpa, a yield strength>150Mpa, and an elongation>10%.

[0083] Example 4

[0084] Step 1: preparing GH3230 alloy powder by using a plasma rotating electrode, and sieving the prepared GH3230 alloy powder to select GH3230 alloy powder with a particle size range of 53 μm to 150 μm as a raw material;

[0085] Step 2, selecting La2O3 ceramic particles with a particle size of 50nm to 100nm as the strengthening phase of the GH3230 nickel-based alloy, the addition amount of La2O3 ceramic particles is 1wt%, and the GH3230 nickel-based alloy powder and the La2O3 ceramic particles are mixed in a mixer for 10 hours, and the obtained powder is recorded as GH3230L;

[0086] Step 3, clean the prefabricated sleeve and core, dry them, and then put the sleeve on the outside of the core, further put the GH3230L alloy powder into the sleeve on the vibration platform, and degas and electron beam seal the sleeve filled with GH3230L powder, the welding current is 50mA, the welding speed is 140° / min, and the number of welding is 2 times;

[0087] Among them, a corresponding sheath is made according to the specifications of the special-shaped tube to be prepared, and the sheath is set on the outside of the core that is compatible with its structure, and the sheath and the core are both made of steel;

[0088] Step 4, hot isostatic pressing the sealed and welded package to obtain a hot isostatic pressed blank. Specifically, the hot isostatic pressing is performed at a temperature of 1170° C., a time of 4 hours, and a pressure of 150 MPa.

[0089] Step 5: machining the obtained hot isostatic pressed blank to remove the jacket and the steel core, thereby obtaining a GH3230 nickel-based alloy special-shaped tube blank;

[0090] Step 6: sequentially heat-treating and finishing the obtained GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0091] Among them, heat treatment includes solution treatment and aging treatment;

[0092] Specifically, during the solution treatment, the temperature is set to 1150°C, the time is 4 hours, and water cooling is adopted; during the aging treatment, the temperature is set to 870°C, the time is 6 hours, and air cooling is adopted to room temperature; after the heat treatment is completed, the GH3230 nickel-based alloy special-shaped tube blank is finely processed to obtain a GH3230 nickel-based alloy special-shaped tube with a tensile strength of 900°C>200Mpa, a yield strength>150Mpa, and an elongation>10%.

[0093] Example 5

[0094] Step 1: preparing GH3230 alloy powder by using a plasma rotating electrode, and sieving the prepared GH3230 alloy powder to select GH3230 alloy powder with a particle size range of 53 μm to 150 μm as a raw material;

[0095] Step 2, selecting CeO2 ceramic particles with a particle size of 50nm to 100nm as the strengthening phase of the GH3230 nickel-based alloy, the addition amount of CeO2 ceramic particles is 1wt%, and the GH3230 nickel-based alloy powder and the CeO2 ceramic particles are mixed in a mixer for 10h, and the obtained powder is recorded as GH3230C;

[0096] Step 3, clean the prefabricated sleeve and core, dry them, and then put the sleeve on the outside of the core, further put the GH3230C alloy powder into the sleeve on the vibration platform, and degas and electron beam seal the sleeve filled with GH3230C powder, the welding current is 50mA, the welding speed is 140° / min, and the number of welding is 2 times;

[0097] Among them, a corresponding sheath is made according to the specifications of the special-shaped tube to be prepared, and the sheath is set on the outside of the core that is compatible with its structure, and the sheath and the core are both made of steel;

[0098] Step 4, hot isostatic pressing the sealed and welded package to obtain a hot isostatic pressed blank. Specifically, the hot isostatic pressing is performed at a temperature of 1200° C., a time of 3 h, and a pressure of 140 MPa.

[0099] Step 5: machining the obtained hot isostatic pressed blank to remove the jacket and the steel core, thereby obtaining a GH3230 nickel-based alloy special-shaped tube blank;

[0100] Step 6: sequentially heat-treating and finishing the obtained GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

[0101] Among them, heat treatment includes solution treatment and aging treatment;

[0102] Specifically, during the solution treatment, the temperature is set to 1170°C, the time is 3 hours, and water cooling is adopted; during the aging treatment, the temperature is set to 880°C, the time is 5 hours, and air cooling is adopted to room temperature; after the heat treatment is completed, the GH3230 nickel-based alloy special-shaped tube blank is finely processed to obtain a GH3230 nickel-based alloy special-shaped tube with a tensile strength of 900°C>200Mpa, a yield strength>150Mpa, and an elongation>10%.

[0103] 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.

[0104] 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 large-size GH3230 nickel-based alloy special-shaped tube, characterized in that: The following steps are involved: Step 1, preparing raw materials: preparing GH3230 alloy powder, and sieving the GH3230 alloy powder to obtain GH3230 alloy powder of a set particle size; Step 2, adding a strengthening phase: uniformly mixing the rare earth oxide particles and the GH3230 alloy powder of a set particle size obtained in step 1 to obtain a GH3230 mixed powder; Step 3, loading: pre-treating the pre-made package and core, and then loading the GH3230 mixed powder obtained in step 2 into the package; Step 4, hot isostatic pressing treatment: the bag containing the GH3230 mixed powder is subjected to degassing and sealing welding treatment, and then subjected to hot isostatic pressing treatment to obtain a hot isostatic pressed blank; Step 5, processing: removing the sheath and the core of the hot isostatic pressed blank to obtain a GH3230 nickel-based alloy special-shaped tube blank, and sequentially performing heat treatment and finishing treatment on the GH3230 nickel-based alloy special-shaped tube blank to obtain a GH3230 nickel-based alloy special-shaped tube of a target size.

2. The method for preparing the large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 1, a plasma rotating electrode is used to prepare GH3230 alloy powder, and the set particle size of the GH3230 alloy powder after screening is 53 μm to 150 μm.

3. The method for preparing the large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 2, the rare earth oxide particles include CeO2, La2O3 or Y2O3, and the particle size of the rare earth oxide particles is 50nm to 100nm.

4. The method for preparing a large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 2, the rare earth oxide particles are added in an amount of 0.5 wt% to 3 wt%, and the rare earth oxide particles and GH3230 alloy powder are mixed in a mixer for 10 h to 40 h.

5. The method for preparing a large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 3, the sheath is made according to the structure and size of the GH3230 nickel-based alloy special-shaped tube to be prepared, and the sheath is arranged on the outside of the core that is adapted to its structure.

6. The method for preparing a large-size GH3230 nickel-based alloy special-shaped tube according to claim 5, characterized in that: The specific process of step 3 is as follows: Step 3.1, the prefabricated package and core are cleaned and dried in sequence, and then the treated package is placed on the outside of the core; Step 3.2: Put the GH3230 mixed powder into a bag on a vibration platform.

7. The method for preparing a large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 4, when the package is subjected to electron beam sealing welding, the sealing welding current is 50 mA to 90 mA, the welding speed is 140 to 260° / min, and the number of welding times is 2 to 3 times.

8. The method for preparing a large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 4, during the hot isostatic pressing treatment, the temperature is set to 1170° C. to 1250° C., the time is 2 h to 4 h, and the pressure is 120 MPa to 150 MPa.

9. The method for preparing a large-size GH3230 nickel-based alloy special-shaped tube according to claim 1, characterized in that: In step 5, the hot isostatic pressed blank obtained in step 4 is machined to remove the jacket and the core; The heat treatment includes solution treatment and aging treatment; during the solution treatment, the temperature is set at 1150°C to 1200°C, the time is 2h to 4h, and water cooling is adopted; during the aging treatment, the temperature is set at 870°C to 900°C, the time is 4h to 6h, and air cooling is adopted to room temperature.

10. A large-size GH3230 nickel-based alloy special-shaped tube, characterized in that: The special-shaped tube is prepared based on the preparation method according to any one of claims 1 to 9, and has the following properties: 900°C tensile strength>200Mpa, yield strength>150Mpa, and elongation>10%.

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