An isothermal near-net forming method for TC4 titanium alloy aero-engine integral blade disk

Abstract

An isothermal near-net forming method for an integral blisk of a TC4 titanium alloy aeroengine, comprising the following steps: 1) Coating the surface of a TC4 titanium alloy bar with a glass lubricant and heating it to T β -(30 - 80) °C; 2) Coating the pre-forging die with a glass lubricant and heating it to T β -(30 - 80) °C; 3) Loading the bar into the pre-forging die to forge an intermediate blank, forging in at least one heat, strain rate ≤ 0.01 s ‑1 , deformation amount 60 - 70%; After forging, water-cool the intermediate blank to room temperature; 4) Heat the intermediate blank to T β -(30 - 80) °C; 5) Coating the finish-forging die with a glass lubricant and heating it to T β -(30 - 80) °C; 6) Loading the intermediate blank into the finish-forging die to press it into an integral blisk forging, forging in at least one heat, strain rate ≤ 0.005 s ‑1 , deformation amount 60 - 70%; After forging, water-cool the integral blisk forging to room temperature; 7) Performing solution treatment on the integral blisk forging and then water-cooling it to room temperature; 8) Performing aging treatment on the integral blisk forging and air-cooling it to room temperature after completion.

Description

Technical Field

[0001] The invention belongs to the field of titanium alloy manufacturing, and in particular relates to an isothermal near-net forming method for a TC4 titanium alloy aero-engine integral blade disk. Background Art

[0002] The fan disk and compressor disk of aircraft engines originally used a combination of wheel disk + blades. There was a tenon on the outside of the wheel disk and a tenon at the root of the blade. The tenon was embedded in the tenon to form a fan disk. With the development of forging technology and processing technology, the integral blade disk has been widely used as one of the iconic technologies of the fourth-generation aircraft engines. This structure eliminates the tenon-tenon connection, prevents gas escape and friction and wear between the tenon-tenon, and has the advantages of reducing weight and improving intake efficiency.

[0003] TC4 titanium alloy is a Ti-AI-V series α-β titanium alloy successfully developed by the United States in 1954. It has moderate room temperature and high temperature strength, good creep resistance and thermal stability, high fatigue performance and crack growth resistance, as well as good fracture toughness and hot salt stress corrosion performance. It is mainly used for fans and compressor discs and blades of aircraft engines, various beams, bulkheads, slide rails, landing gear beams in aircraft structures, shells and pressure vessels of space rockets, and various types of fasteners. It is suitable for manufacturing parts designed using the damage tolerance principle. In the aerospace industry, TC4 alloy semi-finished products account for more than 80% of the total output of various titanium alloy semi-finished products.

[0004] Difficulties of TC4 titanium alloy blisk: The blisk consists of two parts: the disc body and the blades. In addition to the conventional requirements of strength and plasticity, the disc body is mainly tested for low-cycle fatigue, fracture toughness and other properties, while the blades are mainly tested for high-cycle fatigue, creep and other properties. The performance requirements of the disc body and the blades are contradictory to the organizational requirements, which requires strict control of the deformation and temperature during the forging process to obtain the required organization and performance.

[0005] Chinese patent publication number CN115502314A discloses a preparation process for a large-size fine-grained integral blade disk of high uniformity TC4 titanium alloy, which includes forging the alloy ingot at 1050℃~1150℃, then subjecting the obtained blank to one-time upsetting and drawing deformation at 1015℃~1035℃, water cooling after forging, then heating the blank to 880℃~910℃ and keeping it for 12~20h, then heating it to 940℃~980℃ with the furnace for forging, then subjecting the blank to 6~8 times of upsetting and drawing deformation at 935℃~985℃, then forming the blank at 945℃~965℃ to obtain a forged blank; finally, subjecting the obtained forged blank to annealing treatment to obtain an integral blade disk forging blank. This process is suitable for preparing integral blade disk forgings with a size of 600mm to 1500mm and a height of 60mm to 150mm, and the organizational uniformity and performance of the forgings are better than those of traditional processes. The room temperature tensile strength of any part of the forging is ≥950Mpa, the yield is ≥850Mpa, the elongation is ≥15.0%, and the cross-sectional shrinkage is ≥25%. The tensile strength of the 400℃ tensile performance is ≥650MPa; the elongation is ≥20%, and the cross-sectional shrinkage is ≥40%; after the sample is exposed to heat at 400℃ / 100h, the elongation is ≥10.0%, and the cross-sectional shrinkage is ≥20%.

[0006] However, the poor hardenability of TC4 alloy and the increasing size of the integral blade disk have become the main contradictions. Due to the large torsion angle of the fan integral blade disk, the maximum height of the part has increased to more than 200mm. It is difficult to obtain a TC4 titanium alloy integral blade disk with uniform structure and performance between various parts using traditional forging and heat treatment processes. Therefore, a near-net forming process is needed to deal with the above problems. Summary of the invention

[0007] The purpose of the present invention is to provide an isothermal near-net forming method for a TC4 titanium alloy aero-engine integral blade disk, which integrally forges a large-sized TC4 titanium alloy integral blade disk with a diameter of 800-1500 mm and a thickness of 200-350 mm; the technical problem that the difficulty of controlling the uniformity of forging structure and performance due to the increase in specifications is increased exponentially, which easily leads to reduced strength of forgings, coarse structure, and failure to meet use requirements is solved; the room temperature tensile properties of any part of the TC4 titanium alloy integral blade disk forging produced by the present invention are as follows: tensile strength ≥960MPa, yield strength ≥880MPa, elongation ≥12.0%, and cross-sectional shrinkage ≥25%; the high temperature tensile properties at 400°C are as follows: tensile strength ≥650MPa, elongation ≥15%, cross-sectional shrinkage ≥50%, room temperature impact energy ≥28J, and Brinell hardness (indentation diameter) ≥3.35mm.

[0008] To achieve the above object, the technical solution of the present invention is:

[0009] An isothermal near-net forming method for a TC4 titanium alloy aero-engine integral blade disk comprises the following steps:

[0010] 1) Coat the surface of TC4 titanium alloy rod with glass lubricant and heat the TC4 titanium alloy rod to T β - (30~80)℃, heating time T1=D×(0.6~0.9), T1 heating time, unit, min; D is the diameter of TC4 titanium alloy rod, unit, mm;

[0011] 2) The pre-forging die is coated with a layer of glass lubricant and heated to T β - (30~80)℃, keep warm after reaching the temperature;

[0012] 3) Load the TC4 titanium alloy bar into the pre-forging die and forge it into the TC4 titanium alloy intermediate billet of the required shape using a hydraulic press. Forge it at least once, and the strain rate of each time is ≤0.01s -1 , the deformation of each fire is controlled at 60~70%; after forging, the TC4 titanium alloy intermediate billet is water-cooled to room temperature;

[0013] 4) Heat the TC4 titanium alloy intermediate billet to T β - (30~80) ℃, heating time T2=H×(0.6~0.9), T2 heating time, unit, min; H is the thickness of TC4 titanium alloy intermediate billet, unit, mm;

[0014] 5) The final forging die is coated with glass lubricant and heated to T β - (30~80)℃, keep warm after reaching the temperature;

[0015] 6) The heated TC4 titanium alloy intermediate billet is loaded into the final forging die, and the TC4 titanium alloy intermediate billet is pressed into the final TC4 titanium alloy integral blisk forging by a hydraulic press, and forged at least once, and the strain rate of each fire is ≤0.005s -1 The deformation of each fire is controlled at 60~70%; after forging, the TC4 titanium alloy blisk forging is water-cooled to room temperature;

[0016] 7) T-test the TC4 titanium alloy blisk forging β - (30~80)℃, 1~2h solution treatment, and water cooling to room temperature after treatment;

[0017] 8) The TC4 titanium alloy integral blade disk forging was subjected to aging treatment and then air-cooled to room temperature.

[0018] Furthermore, the method further comprises step 9), wherein the TC4 titanium alloy integral blisk forging is subjected to finishing treatment, and the single-side machining allowance of the TC4 titanium alloy integral blisk forging to the rough-machined blank is 3-4 mm.

[0019] Preferably, in step 3), the heated TC4 titanium alloy rod is placed into a heat-insulating pre-forging die within 30 seconds.

[0020] Preferably, in step 3), the TC4 titanium alloy intermediate billet is water-cooled within 30 seconds after the pre-forging is completed, and the cooling rate is ≥5°C / min.

[0021] Preferably, in step 6), the heated TC4 titanium alloy intermediate billet is placed into a heat-insulating final forging die within 30 seconds.

[0022] Preferably, in step 6), the TC4 titanium alloy blisk forging is water-cooled within 30 seconds after the final forging is completed, and the cooling rate is ≥5°C / min.

[0023] Preferably, in step 7), the TC4 titanium alloy integral blade disk forging is water-cooled within 30 seconds after the solution treatment, and the cooling rate is ≥5°C / min.

[0024] Preferably, the aging treatment temperature in step 8) is 550-800° C. and kept at this temperature for 2-10 hours, after which the TC4 titanium alloy blisk forging is air-cooled to room temperature.

[0025] In the method of the present invention:

[0026] Since the TC4 titanium alloy integral blade disk forging of the present invention is large in size and its maximum thickness exceeds the theoretical hardening size of the TC4 titanium alloy material, the cooling rate of air cooling is very slow, which is very unfavorable for the uniform control of the microstructure and performance of the integral blade disk. If only water cooling is performed after solution heat treatment according to conventional processes, it is difficult to reduce the microstructure differences caused by slow cooling after forging.

[0027] The method of the present invention adopts a water cooling process after pre-forging, forming forging and solution heat treatment, which avoids grain growth caused by slow cooling to a certain extent, controls the uniformity of the structure and reduces the difference in each water cooling process; at the same time, the high-temperature β phase undergoes martensitic transformation during the multi-pass rapid water cooling process, and the structure contains many dislocations and twins, which have a serious pinning effect on slip, thereby improving the strength performance of the material.

[0028] The present invention heats and maintains the TC4 titanium alloy bar (intermediate billet) and the forging die to T βIn the following range of 30℃~80℃, since the deformation resistance of the material is negatively correlated with the temperature, there will be no temperature drop during the long-term contact between the bar (intermediate billet) and the die. Therefore, the deformation resistance of the bar (intermediate billet) is very small and the plasticity is good. The high plasticity characteristics at low strain rates are fully utilized to achieve large forming in each pass during the forging process of large-sized integral blade disk forgings. The deformation amount of each fire in the present invention is controlled at 60~70% because according to the existing experimental research results, when the forging deformation amount is less than 20%, the grains of the forging are very coarse; as the deformation amount increases, the grain size will gradually decrease; when the forging deformation amount is greater than 85%, the grains will grow again due to factors such as recrystallization. When the forging deformation amount is 60%~70%, the anisotropy in the microstructure is the smallest, the grains are the finest and most uniform, and the comprehensive performance is the best.

[0029] The present invention adopts a two-phase isothermal forging process to achieve precision forming of forgings. The single-side machining allowance of the forging is 3-4 mm, which is a very large machining allowance compared to ordinary hot die forging, further improving the hardening range of the core of the thick-section integral blade forging, thereby improving the uniformity of the final forging structure.

[0030] The TC4 titanium alloy aero-engine integral blade disk prepared by the method of the present invention has a diameter of 800-1500 mm and a thickness of 200-350 mm; the room temperature tensile properties of any part of the TC4 titanium alloy aero-engine integral blade disk are as follows: tensile strength ≥960 MPa, yield strength ≥880 MPa, elongation ≥12.0%, and cross-sectional shrinkage ≥25%; the 400°C high temperature tensile properties are as follows: tensile strength ≥650 MPa, elongation ≥15%, cross-sectional shrinkage ≥50%, room temperature impact energy ≥28 J, and Brinell hardness (indentation diameter) ≥3.35 mm.

[0031] The microstructure of the TC4 titanium alloy aero-engine integral blade disk of the present invention is a (α+β) two-phase region structure, which is mainly an equiaxed primary α phase distributed on a β transformation structure matrix, with a primary α phase content of 40% to 50% and a size of ≤20μm.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] Since the effective forging temperature range of titanium alloy is very narrow (within 100℃) and the thermal conductivity is poor, the die temperature in the existing conventional forging process is lower than the billet temperature, and the heat of the billet is quickly transferred to the die, causing a significant temperature drop on its surface, resulting in a continuous increase in deformation resistance and a continuous decrease in plasticity, and ultimately poor surface quality and uneven performance structure of the forging. Therefore, the forgings produced by the existing conventional forging process have a relatively large machining allowance and a relatively fast deformation speed.

[0034] The present invention adopts isothermal forging process and strictly controls the strain rate during the forming forging process (using a very small strain rate, the pre-forging strain rate is ≤0.01s -1 , final forging strain rate ≤ 0.005s -1 ), the die and the blank are always stably under the same high temperature conditions, the dynamic recrystallization and dynamic recovery processes during deformation are close to equilibrium, which significantly reduces the residual stress caused by forging deformation, and is beneficial to improving the dimensional control accuracy in the subsequent processing; at the same time, a very small strain rate can achieve a single large deformation (deformation of more than 60%), which can fully break the original grains and obtain uniform and fine dual-state structure intermediate blanks and forgings, especially the equiaxed primary α phase size ≤20μm, which is fully beneficial to improve the strength and plasticity of the integral blade.

[0035] The TC4 titanium alloy integral blade disk forging described in the present invention is large in size, with a thickness of more than 200 mm, and the thickest can reach 350 mm, which exceeds the theoretical hardening size of TC4 titanium alloy material. Therefore, the present invention continuously adopts three water cooling processes during pre-forging, forming forging and solution heat treatment, making full use of rapid cooling to obtain unsaturated transformation structure and fine equiaxed primary α phase (equiaxed primary α phase size ≤ 20μm), providing a basis for the final aging heat treatment; at the same time, in the process of cooling the billet from high temperature to room temperature, the structure will grow, and water cooling can greatly increase the cooling rate of the core of the billet compared to air cooling, shorten the cooling time, and effectively reduce the organizational differences between the surface and the core of the large-size billet (forging), and finally obtain an integral blade disk forging with uniform organization, high strength and plasticity. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 This is a microstructure photograph of the core of the forging in Example 1 of the present invention;

[0037] Figure 2 This is a microstructure photograph of the forging near the surface in Example 1 of the present invention;

[0038] Figure 3 This is a microstructure photograph of the core of the forging in Comparative Example 1 of the present invention;

[0039] Figure 4 This is a microstructure photograph of the forging near the surface in Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0040] The present invention will be further described below in conjunction with the embodiments and drawings.

[0041] The isothermal near-net forming method of the TC4 titanium alloy aero-engine integral blade disk of the present invention comprises the following steps:

[0042] 1) Coat the surface of TC4 titanium alloy rod with glass lubricant and heat the TC4 titanium alloy rod to T β - (30~80)℃, heating time T1=D×(0.6~0.9), T1 heating time, unit, min; D is the diameter of TC4 titanium alloy rod, unit, mm;

[0043] 2) The pre-forging die is coated with a layer of glass lubricant and heated to T β - (30~80)℃, keep warm after reaching the temperature;

[0044] 3) Load the TC4 titanium alloy bar into the pre-forging die and forge it into the TC4 titanium alloy intermediate billet of the required shape using a hydraulic press. Forge it at least once, and the strain rate of each time is ≤0.01s -1 , the deformation of each fire is controlled at 60~70%; after forging, the TC4 titanium alloy intermediate billet is water-cooled to room temperature;

[0045] 4) Heat the TC4 titanium alloy intermediate billet to T β - (30~80) ℃, heating time T2=H×(0.6~0.9), T2 heating time, unit, min; H is the thickness of TC4 titanium alloy intermediate billet, unit, mm;

[0046] 5) The final forging die is coated with glass lubricant and heated to T β - (30~80)℃, keep warm after reaching the temperature;

[0047] 6) The heated TC4 titanium alloy intermediate billet is loaded into the final forging die, and the TC4 titanium alloy intermediate billet is pressed into the final TC4 titanium alloy integral blisk forging by a hydraulic press, and forged at least once, and the strain rate of each fire is ≤0.005s -1 The deformation of each fire is controlled at 60~70%; after forging, the TC4 titanium alloy blisk forging is water-cooled to room temperature;

[0048] 7) T-test the TC4 titanium alloy blisk forging β - (30~80)℃, 1~2h solution treatment, and water cooling to room temperature after treatment;

[0049] 8) The TC4 titanium alloy integral blade disk forging is subjected to aging treatment, and air-cooled to room temperature after the treatment; finally, a TC4 titanium alloy aero-engine integral blade disk with a diameter of 800-1500 mm and a thickness of 200-350 mm is obtained.

[0050] Example 1

[0051] Aircraft engine integral blade disk, forging weight 560kg, diameter 1000mm, thickness 250mm, β phase transformation temperature T β=1000°C, and its manufacturing method comprises the following steps:

[0052] 1) Blanking a Φ400 mm TC4 titanium alloy rod into a rod segment and coating it with glass lubricant, and heating the rod segment to 950° C. for 300 min;

[0053] 2) coating the pre-forging die with glass lubricant and heating it to 950° C., and maintaining the temperature at 950° C. during the production process;

[0054] 3) The heated and insulated TC4 titanium alloy rod segment is placed into the insulated pre-forging die within 30 seconds, and the rod segment is forged into an intermediate billet of the desired shape using a hydraulic press. The forging is performed once, and the strain rate is 0.01s -1 , deformation 65%; put into water and cool to room temperature within 30s after forging, cooling rate 5℃ / min;

[0055] 4) heating the obtained intermediate billet to 950° C. for 300 min;

[0056] 5) Coating the final forging die with glass lubricant and heating it to 950° C., and maintaining the temperature at 950° C. during the production process;

[0057] 6) The heated and insulated TC4 titanium alloy intermediate billet is placed into the insulated final forging die within 30 seconds; the TC4 titanium intermediate billet is pressed into the final TC4 titanium alloy integral blade forging by a hydraulic press, and the forging is performed once, with a strain rate of 0.005s -1 , deformation 65%; after forging, the TC4 titanium alloy blisk forging was taken out within 30 seconds and placed in water to cool to room temperature, with a cooling rate of 6℃ / min;

[0058] 7) The obtained TC4 titanium alloy integral blade disk forging was subjected to a solution treatment at 950°C / 2h, and after the treatment, it was taken out and placed in water within 30s to cool to room temperature at a cooling rate of 5°C / min;

[0059] 8) The cooled TC4 titanium alloy integral blade disk forging is subjected to aging treatment at 720°C, and then air-cooled to room temperature after the treatment.

[0060] Comparative Example 1

[0061] Weight, size and material T of the blisk β Exactly the same as in Example 1, the manufacturing method comprises the following steps:

[0062] 1) Blanking a Φ400 mm TC4 titanium alloy rod into a rod segment and coating it with glass lubricant, and heating the rod segment to 950° C. for 300 min;

[0063] 2) coating the pre-forging die with glass lubricant and heating it to 950° C., and maintaining the temperature at 950° C. during the production process;

[0064] 3) Transfer the heated and insulated TC4 titanium alloy rod segment into an insulated pre-forging die within 30 seconds; use a hydraulic press to forge the rod segment into a TC4 titanium alloy intermediate billet of the desired shape, forging once, with a strain rate of 0.01s -1 , deformation 65%; after forging, air cool to room temperature;

[0065] 4) heating the obtained TC4 titanium alloy intermediate billet to 950° C. for 300 min;

[0066] 5) Coating the final forging die with glass lubricant and heating it to 950° C., and maintaining the temperature at 950° C. during the production process;

[0067] 6) Transfer the heated and insulated TC4 titanium alloy intermediate billet into the insulated final forging die within 30 seconds; use a hydraulic press to press the intermediate billet into the final TC4 titanium alloy integral blade forging, forging once, with a strain rate of 0.005s -1 , deformation 65%; after forging, air cool to room temperature;

[0068] 7) The obtained TC4 titanium alloy integral blade disk forging was subjected to a solution treatment at 950°C / 2h, and after the treatment, it was taken out and placed in water within 30s to cool to room temperature at a cooling rate of 5°C / min;

[0069] 8) The cooled TC4 titanium alloy integral blade disk forging is subjected to aging treatment at 720°C / 2h, and then air-cooled to room temperature after the treatment.

[0070] Comparative Example 2

[0071] Weight, size and material T of the blisk β Exactly the same as in Example 1, the manufacturing method comprises the following steps:

[0072] 1) Blanking a Φ400 mm TC4 titanium alloy rod into a rod segment and coating it with glass lubricant, and heating the rod segment to 900° C. for 300 min;

[0073] 2) coating the pre-forging die with glass lubricant and heating it to 400° C.;

[0074] 3) Transfer the heated and insulated TC4 titanium alloy rod segment into an insulated pre-forging die within 30 seconds; use a hydraulic press to forge the rod segment into a TC4 titanium alloy intermediate billet of the desired shape, forging once, with a strain rate of 0.1s -1 , deformation 65%; put into water and cool to room temperature within 30s after forging, cooling rate 2℃ / min;

[0075] 4) heating the obtained TC4 titanium alloy intermediate billet to 900° C. for 300 min;

[0076] 5) Coating the final forging die with glass lubricant and heating it to 500°C;

[0077] 6) Transfer the heated and insulated TC4 titanium alloy intermediate billet into the insulated final forging die within 30 seconds; use a hydraulic press to press the intermediate billet into the final TC4 titanium alloy integral blade forging, forging once, with a strain rate of 0.05s -1 , deformation 65%; put into water and cool to room temperature within 30s after forging, cooling rate 2℃ / min;

[0078] 7) The obtained TC4 titanium alloy integral blade disk forging was subjected to a solution treatment at 900°C / 2h, and after the treatment, it was taken out and placed in water within 30s to cool to room temperature, with a cooling rate of 2°C / min;

[0079] 8) The cooled TC4 titanium alloy integral blade disk forging is subjected to aging treatment at 720°C / 2h, and then air-cooled to room temperature after the treatment.

[0080] Forging parameters, manufacturing process parameters and finished product performance of the integral blade disk of other embodiments of the present invention, please refer to Tables 1 to 3.

[0081] It can be seen from Tables 1 to 3 that in Example 1, water cooling is performed after pre-forging, forming forging and solution heat treatment. β The same as Example 1, but the cooling method after each forging is air cooling, and water cooling is implemented after solution heat treatment. Due to the slow cooling rate of air cooling, the structure is coarse, the primary α phase content increases, and the strength is also reduced to a certain extent. Therefore, there are obvious differences in the structure size, phase content and strength between Example 1 and Comparative Example 1. In Comparative Example 2, the weight, size and T of the integral blade disk are β The same as Example 1, but the blank temperature, die temperature and strain rate of each forging are out of the process scope of the present invention. Due to the low die temperature and blank temperature, insufficient cooling rate, the primary α phase content is high, and the impact performance is greatly reduced.

[0082] A comparative analysis of the performance and structure of the integral blisk forgings of Example 1 and Comparative Example 1 was performed.

[0083] See also Figure 1 , Figure 2, which shows the microstructure of the forging of Example 1 of the present invention. As shown in the figure, it is a typical two-phase region structure, the primary α phase content is in the range of 40-50%, the α phase size is basically consistent and evenly distributed, the size is ≤20μm, the secondary α phase is small and flaky, and has a certain aspect ratio; combined with the mechanical properties of Table 1, each part has high strength and plasticity, and has excellent comprehensive performance.

[0084] See also Figure 3 , Figure 4 , which shows the microstructure of the forging of Comparative Example 1. The high magnification of Comparative Example 1 is a two-phase region structure, the primary α phase content is 30% on the surface and 70% in the core. The primary α phase content in the core of the forging is significantly greater than that on the surface, and there is an obvious difference in the structure; combined with the mechanical properties in Table 1, since Comparative Example 1 uses air cooling after pre-forging and forming forging, the cooling is slow, resulting in coarse structure, causing the overall strength to fail to meet the requirements.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

[0086]

[0087]

[0088]

Claims

1. An isothermal near-net forming method for a TC4 titanium alloy aero-engine integral blade disk, characterized in that: The steps include: 1) Coat the surface of TC4 titanium alloy rod with glass lubricant and heat the TC4 titanium alloy rod to T β - (30~80)℃, heating time T1=D×(0.6~0.9), T1 heating time, unit, min; D is the diameter of TC4 titanium alloy rod, unit, mm; 2) The pre-forging die is coated with a layer of glass lubricant and heated to T β - (30~80)℃, keep warm after reaching the temperature; 3) Load the TC4 titanium alloy bar into the pre-forging die, and use a hydraulic press to forge the TC4 titanium alloy intermediate billet of the required shape. Forge once, and the strain rate of each fire is ≤0.01s -1 The deformation of each fire is controlled at 60~70%; after forging, the TC4 titanium alloy intermediate billet is water-cooled to room temperature at a cooling rate of 5~8℃ / min; 4) Heat the TC4 titanium alloy intermediate billet to T β - (30~80) ℃, heating time T2=H×(0.6~0.9), T2 heating time, unit, min; H is the thickness of TC4 titanium alloy intermediate billet, unit, mm; 5) The final forging die is coated with glass lubricant and heated to T β - (30~80)℃, keep warm after reaching the temperature; 6) The heated TC4 titanium alloy intermediate billet is loaded into the final forging die, and the TC4 titanium alloy intermediate billet is pressed into the final TC4 titanium alloy integral blisk forging by a hydraulic press, and the forging is performed in one fire, and the strain rate of each fire is ≤0.005s -1 The deformation of each fire is controlled at 60~70%; after forging, the TC4 titanium alloy integral blade forging is water-cooled to room temperature, and the cooling rate is 5~8℃ / min; 7) T-test the TC4 titanium alloy blisk forging β - Solution treatment at 30-80°C for 1-2h, followed by water cooling to room temperature at a cooling rate of 5-8°C / min; 8) The TC4 titanium alloy integral blade disk forging was subjected to aging treatment and then air-cooled to room temperature.

2. The method according to claim 1, characterized in that include: Step 9), the TC4 titanium alloy integral blade disk forging is processed and finished, and the single-side processing allowance of the TC4 titanium alloy integral blade disk forging to the rough processing blank is 3~4mm.

3. The method according to claim 1, characterized in that: Step 3) The heated TC4 titanium alloy bar is placed into a heat-insulating pre-forging die within 30 seconds.

4. The method according to claim 1 or 3, characterized in that: Step 3) After the pre-forging is completed, the TC4 titanium alloy intermediate billet is water-cooled within 30 seconds.

5. The method according to claim 1, characterized in that: Step 6) The heated TC4 titanium alloy intermediate billet is placed into the heat-insulating final forging die within 30 seconds.

6. The method according to claim 1 or 5, characterized in that: Step 6) After the final forging is completed, the TC4 titanium alloy integral blade disk forging is water-cooled within 30 seconds.

7. The method according to claim 1, characterized in that: Step 7) The TC4 titanium alloy integral blade disk forging is water-cooled within 30 seconds after the solution treatment.

8. The method according to claim 1, characterized in that: Step 8) The aging treatment temperature is 550-800° C. and kept for 2-10 hours, after which the TC4 titanium alloy blisk forging is air-cooled to room temperature.

9. A TC4 titanium alloy aero-engine integral blade disk prepared by the method according to any one of claims 1 to 8, characterized in that: The diameter of the TC4 titanium alloy aero-engine integral blade disk is 800~1500mm, and the thickness is 200~350mm; the room temperature tensile properties of any part of the TC4 titanium alloy aero-engine integral blade disk are as follows: tensile strength ≥960MPa, yield strength ≥880MPa, elongation ≥12.0%, and cross-sectional shrinkage ≥25%; the 400℃ high temperature tensile properties are as follows: tensile strength ≥650MPa, elongation ≥15%, cross-sectional shrinkage ≥50%, room temperature impact energy ≥28J, and Brinell hardness indentation diameter ≥3.35mm.

10. The TC4 titanium alloy aero-engine integral blade disk according to claim 9, characterized in that: The microstructure of the TC4 titanium alloy aero-engine integral blade disk is a (α+β) two-phase region structure, which is mainly an equiaxed primary α phase distributed on a β transformation structure matrix, with a primary α phase content of 40% to 50% and a size of ≤20μm.

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