A nickel-based alloy dual-property hollow turbine disk, a method for manufacturing the same and a hollow turbine disk forging die

Abstract

The present application relates to the field of plastic forming hot working, in particular to a kind of nickel-based alloy double-property hollow turbine disc and its preparation method and hollow turbine disc forging die.The preparation method provided by the present application realizes double-property turbine disc forming control property by using a set of tooling die with cooling system, and in the process of forging forming, by the ingenious combination of local deformation of turbine disc hub, pressure maintaining and gradual cooling solid solution heat treatment technology of different parts partition, fine grain structure and fine globular gamma' precipitate phase in hub part, coarse grain structure and large size block gamma' precipitate phase in disc rim part and medium size grain structure and gamma' precipitate phase in web transition region are obtained.In the forming method of the present application, by reasonably matching the deformation amount and gradient cooling of different regions of disc hub and disc rim, the turbine disc after forming does not need to be subjected to gradient heat treatment in special heat treatment tooling, the production efficiency is improved, the production cost is reduced, and good economic benefits are obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of plastic forming hot working, in particular to a nickel-based alloy dual-property hollow turbine disk, a preparation method thereof and a hollow turbine disk forging die. BACKGROUND

[0002] The turbine disk is a key hot end component of an aero-engine. In the working state, the working temperature of the entire disk gradually decreases from the disk rim to the disk hub along the diameter direction. The working condition characteristics put forward the requirements of tailored properties for the disk. The disk rim is connected with the blade, the working temperature is high due to the friction of the airflow, but the stress is small, and the material is required to have high creep property and fracture toughness. The disk hub is connected with the shaft, the working temperature is relatively low, but it bears a large centrifugal force brought by the rotation of the disk, and the material is required to have high strength, plasticity and low cycle fatigue strength.

[0003] The early dual-property disk is prepared from dissimilar alloy materials, that is, the disk hub part is selected from a high-strength alloy, and the disk rim part is selected from another alloy resistant to creep. The two alloys are combined by a connecting method (such as welding, hot isostatic pressing and the like). This connecting method has problems such as poor weldability of the material, difficult control of joint defects and unsatisfactory microstructure, and the connecting interface of the disk is the weakest link of the disk body, which seriously restricts the development and application of the disk. At present, the dual-structure / dual-property disk prepared from one alloy and having different microstructures in the disk hub and disk rim parts has become a hot spot, that is, a fine-grained structure is obtained in the disk hub part to ensure high strength, a coarse-grained structure is obtained in the disk rim part to ensure good endurance and creep properties, and the transition region (the web position) between the disk hub and disk rim parts requires a smooth transition of the grain structure. This kind of disk avoids the safety hazards that may be caused by the connection between dissimilar metals, fully meets the working condition requirements of high thrust-to-weight ratio engines, and significantly improves the safety factor of the entire disk.

[0004] For the dual-property high-temperature alloy turbine disk, obtaining a dual-property disk with a single alloy structure mainly includes two processes of ultra-fine-grained high-strength bar preparation and gradient heat treatment. First, an ultra-fine-grained bar is used to prepare a forging blank, and then the forging blank is subjected to gradient heat treatment, that is, the fine-grained blank is subjected to gradient heat treatment to make the grains in the disk rim part grow, so as to obtain coarse-grained structure, and meet the endurance, creep and crack propagation resistance properties. Research shows that, in terms of microstructure, the dual-property disk not only differs in grain size, but also differs in size and morphology of γ' phase. That is, the mechanical properties of the dual-property disk are not only related to the grain size, but also have an important relationship with the size and morphology of the γ' phase. To meet the dual-property requirements of the disk hub and the disk rim at the same time, it is a big challenge to the hot working technology. SUMMARY

[0005] Therefore, the technical problem to be solved by the present application is to provide a nickel-based alloy dual-property hollow turbine disc, a preparation method thereof and a hollow turbine disc forging die.

[0006] The present application provides a preparation method of a nickel-based alloy dual-property hollow turbine disc, comprising the following steps:

[0007] S1) performing large deformation amount closed finish forging on a turbine disc pancake blank with a disc hub thickness greater than a disc rim thickness in a die to obtain a turbine disc forging blank; the deformation amount of the large deformation amount closed finish forging is the difference between the disc hub thickness and the disc rim thickness of the turbine disc pancake blank;

[0008] S2) cooling the turbine disc forging blank obtained in step S1) from the disc hub to the disc rim in a decreasing cooling effect, and then performing heat treatment to obtain a nickel-based alloy dual-property hollow turbine disc.

[0009] The preparation method of the nickel-based alloy dual-property hollow turbine disc provided by the present application is suitable for turbine discs with blank made of nickel-based alloy, and in particular suitable for sub-solid solution heat treatment nickel-based alloy with blank made of solid solution heat treatment temperature lower than the complete recrystallization temperature of the strengthening phase, to prevent the turbine disc internal organization, especially the disc hub grain organization, from being severely coarsened. In some embodiments of the present application, the nickel-based alloy is GH4151 nickel-based alloy, and the element composition includes C, Co, Cr, W, Mo, Al, Ti, Nb and Ni, etc.

[0010] The present inventors have creatively found that, in the forging forming process of the dual-property hollow turbine disc, by reasonably matching the deformation amount and gradient cooling of different regions of the disc hub and the disc rim, a dual-property hollow turbine disc that meets the disc hub and the disc rim at the same time can be prepared, with high mechanical properties and without subsequent gradient heat treatment.

[0011] The present application first performs large deformation amount closed finish forging on a turbine disc pancake blank with a disc hub thickness greater than a disc rim thickness in a die to obtain a turbine disc forging blank. The turbine disc pancake blank of the present application is a "top" turbine disc preform pancake blank, which is a turbine disc pancake blank with a disc hub thickness greater than a disc rim thickness, and presents a shape with a thick middle and thin edges. The turbine disc pancake blank of the present application is also provided with a center hole at the disc hub position. The difference between the disc hub thickness and the disc rim thickness of the turbine disc pancake blank is 50-80% of the disc hub thickness of the turbine disc pancake blank. In some embodiments of the present application, the disc hub thickness of the turbine disc pancake blank with a disc hub thickness greater than a disc rim thickness is 140-160 mm, and the disc rim thickness is 30-50 mm.

[0012] In some embodiments of the present application, the turbine disk blank with the hub thickness greater than the rim thickness is prepared by the following method: blanking high-temperature alloy bars according to the shape and volume of the turbine disk forging blank to be prepared, preparing a cylindrical turbine disk preform blank by isothermal forging, and further processing the cylindrical turbine disk preform blank into a turbine disk blank with the hub thickness greater than the rim thickness; wherein the average grain size of the selected high-temperature alloy bar structure is 6-7 levels.

[0013] Before the large deformation closed final forging of the turbine disk blank in the present application, the turbine disk blank is heated, and the heating temperature is consistent with the solid solution heat treatment temperature of the same brand alloy. In the present application, the turbine disk blank is heated to 750-850℃ for heat preservation, heated to 900-1000℃ for heat preservation, and heated to the final forging heating temperature for heat preservation. The final forging heating temperature is 30-80℃ below the complete re-dissolution temperature of the gamma prime strengthening phase of the nickel-based alloy, and the final forging heating temperature in the present application is 1100-1150℃. The heating rate is 50-200℃ / h. The heat preservation time is 1-2 min / mm in terms of the hub thickness of the turbine disk blank.

[0014] When the large deformation closed final forging of the turbine disk blank is performed in the present application, the deformation amount of the large deformation closed final forging is the difference between the hub thickness and the rim thickness of the turbine disk blank. In the present application, the large deformation closed final forging of the turbine disk blank is performed in a die, and the die includes an upper die insert and a lower die insert. In some embodiments of the present application, the turbine disk blank is placed in the lower die insert of the die, ensuring that the turbine disk blank and the lower die insert of the die are coaxial, and then the large deformation closed final forging of the turbine disk blank is performed in the axial direction. The reduction speed of the large deformation closed final forging in the present application is 0.01-10 mm / s. The method of the present application obtains a fine-grained structure by large deformation of the hub part, so it is not necessary to prepare ultra-fine-grained bars by multiple large deformation processes, reducing the forming times.

[0015] When the large deformation closed final forging of the turbine disk blank is performed in the present application, the forging method used is isothermal forging, i.e. the die temperature is consistent with the forging heating temperature of the turbine disk blank. When the large deformation closed final forging of the turbine disk blank is performed in the present application, it is also necessary to spray lubricant. The sprayed lubricant is graphite lubricant with good heat conductivity, which prevents the influence of the cooling system of the upper and lower dies on the heat transfer of the turbine disk forging after the final forging is completed, affecting the cooling effect.

[0016] After the large deformation closed final forging of the turbine disc blank, the present application further comprises pressure holding for 5-30 minutes. During the pressure holding process, the temperature of the isothermal forging die remains unchanged, which promotes the static recrystallization of the alloy and is conducive to the dissolution of more strengthening phases into the matrix so as to facilitate the precipitation of strengthening phases of different sizes and morphologies during the subsequent cooling process.

[0017] After the large deformation closed final forging of the turbine disc blank, the present application further comprises pressure holding for 5-30 minutes. During the pressure holding process, the temperature of the isothermal forging die remains unchanged, which promotes the static recrystallization of the alloy and is conducive to the dissolution of more strengthening phases into the matrix so as to facilitate the precipitation of strengthening phases of different sizes and morphologies during the subsequent cooling process.

[0018] After the large deformation closed final forging of the turbine disc blank, the present application further comprises pressure holding for 5-30 minutes. During the pressure holding process, the temperature of the isothermal forging die remains unchanged, which promotes the static recrystallization of the alloy and is conducive to the dissolution of more strengthening phases into the matrix so as to facilitate the precipitation of strengthening phases of different sizes and morphologies during the subsequent cooling process.

[0019] The application provides a nickel-based alloy double-property hollow turbine disc obtained by the preparation method.

[0020] The application further provides a hollow turbine disc forging die, which comprises an upper die and a lower die.

[0021] The number of the spiral cooling pipes is more than 3, and the diameter of the spiral cooling pipes increases by 5-15 mm from the center to the edge of each circle. In some embodiments of the application, the number of the spiral cooling pipes is 3, and the diameter of the spiral cooling pipes is 25-35 mm, 35-45 mm and 45-55 mm from the center to the edge of each circle. The cooling pipes arranged in the center of the hollow turbine disc forging die are arranged more closely than those arranged in the edge, and the unit area of the center with more closely arranged cooling pipes can take away more heat, so that the cooling speed of the center is faster than that of the edge, thereby achieving the effect of gradient cooling of the turbine disc forging blank from the center to the edge. The distribution of the spiral cooling pipes arranged in the upper die and the lower die of the hollow turbine disc forging die is consistent, and is distributed in the anticlockwise or clockwise direction, which is helpful to obtain uniform cooling effect of the hollow turbine disc forging blank.

[0022] The cooling medium inlet is arranged on the pipe at the center position of the spiral cooling pipe, and the cooling medium outlet is arranged on the pipe at the edge position, so that the cooling medium can sequentially cool the center and the edge of the hollow turbine disc forging die. The inlet of the upper die cooling pipe and the lower die cooling pipe of the hollow turbine disc forging die is arranged at the center of the die, and the outlet is arranged at the edge of the die, so that the temperature of the cooling medium at the outlet is higher than that at the inlet after flowing through the heated die, thereby facilitating faster cooling effect of the center of the turbine disc than the edge, and further constructing a cooling system with gradually decreasing cooling effect from the center of the disc hub to the disc edge.

[0023] The center position of the lower die of the hollow turbine disc forging die is further provided with an axial cooling pipe specially passing through the center hole of the hollow turbine disc forging blank, so as to ensure faster cooling effect of the turbine disc hub part during the solid solution heat treatment after the finish forging, to establish a cooling gradient with gradually decreasing cooling speed from the disc hub to the disc edge, and to ensure that the strengthening phases with different morphologies and sizes are precipitated in different regions of the disc.

[0024] The application provides a nickel-based alloy double-property hollow turbine disc, a preparation method thereof and a hollow turbine disc forging die. The preparation method provided by the application realizes double-property turbine disc forming control by adopting a set of tooling die with a cooling system. During the forging forming process, the turbine disc hub is partially deformed, pressure is maintained, and the gradual control cooling solid solution heat treatment technology is ingeniously combined in different parts, so that the fine grain size 10-12 grade fine grain structure and fine spherical γ' precipitated phase of the hub part, the coarse grain size 6-7 grade coarse grain structure and large size block γ' precipitated phase of the rim part and the medium size grain structure and γ' precipitated phase in the web transition region are obtained. In the forming method of the application, by reasonably matching the deformation amount and gradient cooling of different regions of the hub and the rim, the turbine disc does not need to be subjected to gradient heat treatment in a special heat treatment tooling after forming, the production efficiency is improved, the production cost is reduced, and good economic benefits are obtained. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 It is a structure schematic diagram of the hollow turbine disc preform in the method embodiment 1 of the application;

[0026] Figure 2 It is a structure schematic diagram of the upper die cooling pipe distribution in the method embodiment 1 of the application;

[0027] Figure 3 It is a structure schematic diagram of the lower die cooling pipe distribution in the method embodiment 1 of the application;

[0028] Figure 4 It is a schematic diagram of the initial state of the final forging deformation in the method embodiment 1 of the application;

[0029] Figure 5 It is a schematic diagram of the end state of the final forging deformation in the method embodiment 1 of the application;

[0030] Figure 6 It is a grain microstructure diagram of the hub of the GH4151 alloy turbine disc forging blank in the embodiment 1 of the application;

[0031] Figure 7 It is a grain microstructure diagram of the web transition region of the GH4151 alloy turbine disc forging blank in the embodiment 1 of the application;

[0032] Figure 8 It is a grain microstructure diagram of the rim of the GH4151 alloy turbine disc forging blank in the embodiment 1 of the application;

[0033] Figure 9 It is a precipitated phase morphology microstructure diagram of the hub of the GH4151 alloy turbine disc forging blank in the embodiment 1 of the application;

[0034] Figure 10 The microstructure diagram of precipitated phase morphology of the GH4151 alloy turbine disc forging blank web transition zone of Example 1 of the present application is shown in the figure;

[0035] Figure 11 The microstructure diagram of precipitated phase morphology of the GH4151 alloy turbine disc forging blank disc web of Example 1 of the present application is shown in the figure. DETAILED DESCRIPTION

[0036] The present application discloses a kind of nickel-based alloy double performance hollow turbine disc and its preparation method and hollow turbine disc forging die.The person skilled in the art can improve process parameters appropriately according to the content of the present application.It is particularly pointed out that all similar substitutions and changes are obvious to the person skilled in the art, and they are regarded as including in the present application.The method and application of the present application have been described by preferred embodiments, and relevant personnel can obviously change or appropriately change and combine the method and application of the present application without departing from the content, spirit and scope of the present application, to realize and apply the present application technology.

[0037] The present application is further described below in combination with embodiments:

[0038] Example 1

[0039] Step one, forging pre-made cake blank (1)

[0040] According to the shape and volume of the hollow turbine disc forging blank to be prepared, GH4151 high-temperature alloy bar is cut down, the blank size is Φ120 mm*300 mm, the average grain size of the initial organization of the bar blank is 6 levels, the blank and the die heating temperature are both 1110 DEG C, and the isothermal forging method is used to prepare the turbine disc pre-made cake blank (1);As shown in the figure, Figure 1 Figure 1 The structure diagram of the hollow turbine disc pre-made cake blank in the method embodiment 1 of the present application is shown in the figure.

[0041] Step two, process hollow pre-made blank (26)

[0042] In combination with final forging forming process, the pre-made cake blank is processed into "gyroscope" with disc hub thickness G1 of 150 mm and disc web thickness G2 of 40 mm, and a center hole is processed at the disc hub position, to obtain the hollow pre-made blank (26);

[0043] Step three, prepare forging die

[0044] The cooling system of the final forging die is formed by machining the upper die cooling pipe (23) and the lower die cooling pipe (27) between the upper die (21) and the upper die insert (22), the lower die (28) and the lower die insert (29), the cooling pipe spacing D1=30 mm, D2=40 mm, D3=50 mm, and the cooling pipes are distributed in a clockwise direction; as shown in Figures 2-3 , Figure 2 which is a structure diagram of the distribution of the upper die cooling pipe in the method embodiment 1 of the application, Figure 3 which is a structure diagram of the distribution of the lower die cooling pipe in the method embodiment 1 of the application.

[0045] Step four, heating the hollow preform blank (26)

[0046] The hollow preform blank (26) is placed into a heating furnace with a furnace temperature lower than 300 DEG C for stepwise heating, through the stepwise heating, firstly, the temperature is raised to 800 DEG C at a temperature rising rate of 100 DEG C / h for 3 hours, after the heat preservation is finished, the temperature is raised to 950 DEG C at a temperature rising rate of 100 DEG C / h for 3 hours, after the heat preservation is finished, the temperature is raised to the final forging temperature 1120 DEG C at a temperature rising rate of 60 DEG C / h for heating and heat preservation; the heat preservation time of each stage is calculated according to formula 1.

[0047] T=150 mm x 1.2 min / mm=180 min Formula 1;

[0048] In the formula, T is the heat preservation time of the hollow turbine disc preform blank (26), and G2 is the initial thickness of the disc hub of the hollow turbine disc preform blank (26).

[0049] Step five, closed final forging of the hollow preform blank (26) with large deformation

[0050] After the hot penetration of the hollow preform blank (26), the hollow preform blank (26) is sprayed with graphite lubricant and then quickly transferred to the lower die (28), so as to ensure that the hollow preform blank (26) and the lower die (28) are coaxial, and the hollow preform blank (26) is subjected to final forging in the axial direction, the downward deformation amount is 110 mm, and the downward speed is 0.5 mm / s, thereby obtaining a turbine disc forging blank (30); as shown in Figures 4-5 , Figure 4 which is a schematic diagram of the initial state of the final forging deformation in the method embodiment 1 of the application, Figure 4 In the formula, 21 is an upper die insert, 22 is an upper die, 23 is an upper die cooling pipe, 24 is a heat insulation gasket, 25 is an upper die sleeve, 26 is a preform blank, 27 is a lower die cooling pipe, 28 is a lower die, 29 is a lower die insert, and 210 is a lower die sleeve. Figure 5 which is a schematic diagram of the final state of the final forging deformation in the method embodiment 1 of the application, Figure 5 In the formula, 30 is a dual-performance turbine disc blank, which is obtained by Figure 4The 26-preform blank is obtained after large deformation amount closed finish forging.

[0051] Step six, the hollow turbine disk forging blank (30) is pressure-kept

[0052] After finish forging, the turbine disk forging blank (30) is pressure-kept through the upper die (21) and the upper die insert (22), the lower die (28) and the lower die insert (29), and the pressure-keeping time is 10 min;

[0053] Step seven, the hollow turbine disk forging blank (30) is gradient cooled

[0054] After the pressure-keeping, the upper die (21) and the upper die insert (22), the lower die (28) and the lower die insert (29) and the hollow turbine disk forging blank (30) are quickly taken out from the die heating furnace, the upper die cooling pipeline (23) and the lower die cooling pipeline (27) are connected with cooling water, the cooling water flow speed V is 5 mm / s, the hub, the web plate and the disk rim part of the hollow turbine disk forging blank (30) are gradient cooled, and the hollow turbine disk forging blank (30) is taken out from the die and air-cooled after the temperature of the disk rim part is reduced to below 800 DEG C;

[0055] Step eight, the hollow turbine disk forging blank (30) is heat treated

[0056] The cooled GH4151 high-temperature alloy hollow turbine disk forging blank is treated at 850 DEG C for 8 hours / air-cooled and at 760 DEG C for 16 hours / air-cooled.

[0057] Comparative example 1

[0058] The hollow preform blank (26) prepared by the same method as in example 1 is finish forged with small deformation amount in step five, that is, the hot penetrated hollow preform blank (26) is quickly transferred to the lower die (28) after being sprayed with graphite lubricant, the hollow preform blank (26) and the lower die (28) are coaxial, and the hollow preform blank (26) is finish forged along the axial direction, the lower pressing deformation amount is 30 mm (deformation amount 20%), and the lower pressing speed is 0.5 mm / s, to obtain the turbine disk forging blank (30). The subsequent treatment of the turbine disk forging blank is consistent with steps six to eight in the example.

[0059] Comparative example 2

[0060] The hollow turbine disk forging blank (30) prepared by the same method as in Example 1 is uniformly cooled in Step 7, i.e. without the gradient cooling system innovatively designed in the method of the application, but with the uniformly arranged cooling pipes in the mold structure to uniformly cool the hollow turbine disk forging blank (30), and after the temperature of the disk rim portion of the hollow turbine disk forging blank (30) is reduced to below 800℃, it is taken out of the mold and air-cooled. The subsequent processing of the turbine disk forging blank is consistent with Step 8 in the example.

[0061] Through the tests in Example 1 and Comparative Examples 1 and 2 above, the room temperature tensile mechanical properties of the nickel-based wrought superalloy turbine disk obtained are shown in Table 1:

[0062] Table 1

[0063]

[0064] As can be seen from Table 1, compared with the small deformation amount final forging of Comparative Example 1 and the traditional uniform cooling system of Comparative Example 2, the nickel-based superalloy of Example 1 of the method of the application simultaneously obtains better room temperature tensile strength and high temperature endurance life, which are both significantly better than those of the comparative examples. Figures 6-8 The grain microstructure diagram of the GH4151 alloy turbine disk forging blank of Example 1 of the application is shown, wherein Figure 6 is the grain microstructure diagram of the disk hub of the GH4151 alloy turbine disk forging blank of Example 1 of the application, Figure 7 is the grain microstructure diagram of the web transition zone of the GH4151 alloy turbine disk forging blank of Example 1 of the application, Figure 8 is the grain microstructure diagram of the disk rim of the GH4151 alloy turbine disk forging blank of Example 1 of the application. Figures 9-11 The precipitated phase morphology microstructure diagram of the GH4151 alloy turbine disk forging blank of Example 1 of the application is shown, wherein Figure 9 is the precipitated phase morphology microstructure diagram of the disk hub of the GH4151 alloy turbine disk forging blank of Example 1 of the application, Figure 10 is the precipitated phase morphology microstructure diagram of the web transition zone of the GH4151 alloy turbine disk forging blank of Example 1 of the application, Figure 11 is the precipitated phase morphology microstructure diagram of the disk rim of the GH4151 alloy turbine disk forging blank of Example 1 of the application. It can be seen that Figures 6-8 the grain size of the turbine disk prepared by the method of the application gradually increases from the disk hub to the disk rim region, wherein the grain size of the disk hub region is ASTM 8~10 grade, and the grain size of the disk rim region is ASTM 7~8 grade. It can be seen that Figures 9-11It can be known that the size of the secondary γ' strengthening phase precipitated from the turbine disc prepared by the method gradually decreases from the disc hub to the disc rim region, the cooling speed of the disc rim region is slower, the secondary γ' strengthening phase mainly presents block distribution, and the average size is about 240 μm; the cooling speed of the disc hub region is fast, the secondary γ' strengthening phase presents spherical dispersion distribution, and the average size is about 130 μm; the further smaller γ' strengthening phase further improves the service strength of the nickel-based alloy disc hub region. The turbine disc formed by the method does not need to be subjected to gradient heat treatment in a special heat treatment tooling, the production efficiency is improved, the production cost is reduced, and good economic benefits are obtained.

[0065] The above merely describes a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can make equivalent replacements or changes according to the technical scheme and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method of manufacturing a nickel-based alloy dual property hollow turbine disk, characterized by, Comprise the following steps: S1) large deformation amount closed final forging of turbine disc pancake blank with disc hub thickness greater than disc rim thickness in a mold to obtain turbine disc forging blank; the deformation amount of the large deformation amount closed final forging is the difference between the disc hub thickness and the disc rim thickness of the turbine disc pancake blank; the difference between the disc hub thickness and the disc rim thickness of the turbine disc pancake blank is 60-80% of the disc hub thickness of the turbine disc pancake blank; before the large deformation amount closed final forging of the turbine disc pancake blank, it also comprises heating the turbine disc pancake blank to 750-850 DEG C for heat preservation, heating to 900-1000 DEG C for heat preservation, and heating to 1100-1150 DEG C for heat preservation; The heating rate is 50-200 DEG C / h; the heat preservation time is 1-2 min / mm of the disc hub thickness of the turbine disc pancake blank; S2) turbine disc forging blank obtained in step S1) is cooled from disc hub to disc rim by cooling medium through vortex-shaped cooling pipeline with cooling effect decreasing from disc hub to disc rim, and then heat treated to obtain nickel-based alloy dual-property hollow turbine disc; the number of turns of the vortex-shaped cooling pipeline is more than 3 turns, and the pipeline diameter of the vortex-shaped cooling pipeline increases by 5-15 mm from the center to the edge of each turn.

2. The production method according to claim 1, characterized by, In step S1), the disc hub thickness of the turbine disc pancake blank is 140-160 mm, and the disc rim thickness is 30-50 mm.

3. The production method according to claim 1, characterized by, In step S1), the reduction rate of the large deformation amount closed final forging is 0.01-10 mm / s.

4. The method of claim 1, wherein, In step S1), after the large deformation amount closed final forging of the turbine disc pancake blank, it also comprises pressure holding for 5-30 min.

5. The preparation method according to claim 1, characterized in that, In step S2), the number of turns of the vortex-shaped cooling pipeline is 3 turns, and the pipeline diameter of the vortex-shaped cooling pipeline is 25-35 mm, 35-45 mm and 45-55 mm from the center to the edge of each turn in turn.

6. The nickel-based alloy dual-property hollow turbine disc obtained by the preparation method of any one of claims 1-5.

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