Application of dual-channel powder feeding process in the preparation of aero-engine turbine disk blanks

Abstract

This invention discloses the application of a dual-channel powder feeding process in the preparation of turbine disk blanks for aero-engines, belonging to the field of aero-engine turbine disk manufacturing technology. It utilizes an electric arc powder feeding additive manufacturing process to deposit high-temperature alloy powder through a dual-channel system with gradient proportions, forming a material gradient distribution in the disk core, transition, and edge regions. Simultaneously, a synchronous micro-forging process is employed to apply dynamic mechanical deformation to the newly deposited layer in a high-temperature plastic state. The resulting turbine disk blank undergoes hot isostatic pressing to eliminate internal defects, followed by high-temperature homogenization annealing in a vacuum furnace to improve microstructure uniformity. Finally, solution treatment and aging treatment are used to obtain the desired mechanical properties, thus producing the turbine disk blank. This process achieves precise gradient control of material composition in different regions of the turbine disk, effectively improving and regulating the microstructure of the deposited material during manufacturing, and reducing metallurgical defects.

Description

Technical Field

[0001] This invention relates to the field of aero-engine turbine disk manufacturing technology, specifically to the application of a dual-channel powder feeding process in the preparation of aero-engine turbine disk blanks. Background Technology

[0002] The turbine disk of an aero-engine is one of the core hot-end components of the engine. Operating under multiple extreme conditions, including high temperature, high speed, and complex stress, it places extremely stringent requirements on the comprehensive performance of the materials. Different regions of the turbine disk, such as the center, transition zone, and rim, experience different temperatures and stress states, thus requiring different microstructures and properties, such as strength, toughness, fatigue resistance, creep resistance, and oxidation resistance. For example, the center region typically requires materials with high yield strength, good low-cycle fatigue performance, and fracture toughness to withstand cyclic loads during startup and shutdown; while the rim region requires materials with excellent creep resistance, endurance strength, and microstructure stability to withstand the challenges of long-term high-temperature operation.

[0003] Traditional turbine disk manufacturing processes, such as integral forging or powder metallurgy hot isostatic pressing, typically employ a single-component high-temperature alloy material for integral fabrication. While this method is technologically mature, it has limitations in meeting the specific performance requirements of different regions of the turbine disk. Often, performance in one region is sacrificed at the expense of another, making it difficult to achieve optimal matching of material properties across different regions. This limits further improvements in the overall performance of the turbine disk and the increase in the engine's thrust-to-weight ratio.

[0004] In recent years, additive manufacturing (AM) technology, especially powder-feed-based directional energy deposition technologies (such as arc additive manufacturing or laser melting deposition), has provided a new technological approach for the manufacture of high-performance turbine disks due to its unique advantages in forming complex structural parts, material design freedom, and near-net-shape forming. Theoretically, additive manufacturing technology can achieve gradient distributions of material composition and microstructure, thereby producing functionally graded materials (FGM) turbine disks that meet specific performance requirements in different regions.

[0005] However, in practical applications, existing single-channel powder feeding additive manufacturing processes have limited capabilities in precisely controlling the gradient ratio of multi-component, multi-part powders, making it difficult to flexibly and accurately achieve smooth transitions and precise control of material composition in different regions of the turbine disk. Furthermore, the rapid melting and solidification characteristics of additive manufacturing easily lead to coarse microstructures, elemental segregation, internal porosity, or lack of fusion in the resulting deposited material. These defects significantly affect the material's mechanical properties and service reliability. Although subsequent heat treatment processes can improve the microstructure and properties to some extent, eliminating all primary defects and obtaining an ideal fine and uniform grain structure remains a challenge. Summary of the Invention

[0006] This invention discloses the application of a dual-channel powder feeding process in the preparation of turbine disk blanks for aero-engines. A turbine disk blank is prepared, which realizes precise gradient control of material composition in different regions of the turbine disk. It can effectively improve and regulate the microstructure of the deposited material during the manufacturing process, reduce metallurgical defects, and solve the technical problems of insufficient performance, short service life and low reliability of aero-engine turbine disks in the prior art.

[0007] This invention claims protection for the application of a dual-channel powder feeding process in the preparation of turbine disk blanks for aero-engines. The process involves using an arc-feeding additive manufacturing process to deposit high-temperature alloy powder through a dual-channel system in a gradient proportion, creating a material gradient distribution in the disk core, transition, and edge regions. Simultaneously, a synchronous micro-forging process is employed to apply dynamic mechanical deformation to the newly deposited layer in a high-temperature plastic state. The resulting turbine disk blank undergoes hot isostatic pressing, followed by high-temperature homogenization annealing in a vacuum furnace. Finally, solution treatment and aging treatment are used to obtain the turbine disk blank.

[0008] As a further improvement to the present invention, the following steps are included:

[0009] S1. Arc-fed powder additive manufacturing process: High-temperature alloy powder is deposited in a gradient ratio through a dual-channel powder feeding system, specifically including: additive manufacturing in the core area, additive manufacturing in the transition area, and additive manufacturing in the edge area. The gradient distribution of materials is achieved by adjusting the powder feeding rate of the two powder feeding channels.

[0010] The general parameters of the electric arc powder feeding additive manufacturing process are: powder feeding speed in the mixing powder channel, electric arc current, electric arc voltage, deposition layer thickness, interlayer residence time, and protective atmosphere.

[0011] S2. Synchronous micro-forging process: While the material is being deposited, mechanical deformation is applied to the newly deposited material layer that is in a high-temperature plastic state. Dynamic extrusion or rolling is applied to the newly deposited layer through a micro-rolling and forging mechanism.

[0012] S3. Hot isostatic pressing heat treatment process: Hot isostatic pressing is performed on the turbine disk blanks that have completed additive manufacturing and synchronous micro forging.

[0013] S4. Homogenization treatment: The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace;

[0014] S5. Solution treatment + aging heat treatment process: The homogenized billet is subjected to solution treatment and aging treatment in a vacuum furnace to obtain turbine disk blank.

[0015] As a further improvement of the present invention, in S1, the gradient ratio of additive manufacturing in the disk core area is as follows: the powder feeding rate of channel one is set to 2.5-4.0 m / min, and the powder feeding rate of channel two is set to 0.5-1.5 m / min or 0 m / min.

[0016] The gradient ratio of additive manufacturing in the transition region is as follows: as the additive manufacturing path moves from the center of the disk to the edge of the disk, the powder feeding rate of channel one gradually decreases, and the powder feeding rate of channel two gradually increases.

[0017] The gradient ratio of additive manufacturing in the disk edge area is as follows: the powder feeding rate of channel one is set to 0.5-1.5 m / min or 0 m / min, and the powder feeding rate of channel two is set to 2.5-4.0 m / min.

[0018] As a further improvement of the present invention, in S1, the general parameters of the arc-feeding additive manufacturing process are specifically as follows:

[0019] Powder feeding speed in the mixing channel: 1~5m / min;

[0020] Arc current: 100~300A;

[0021] Arc voltage: 15~25V;

[0022] Deposition layer thickness: 0.5~2mm;

[0023] Inter-floor dwell time: 10~30s;

[0024] Protective atmosphere: high-purity Ar gas, flow rate 10-25 L / min, temperature controlled at -15~0℃.

[0025] As a further improvement of the present invention, in step S2, the parameters for applying mechanical deformation are:

[0026] Forging timing: Immediately after each or several layers of material have solidified and are at a high temperature of 800-1150℃;

[0027] Forging method: The new deposited layer is subjected to unidirectional or multidirectional dynamic extrusion or rolling through a micro-rolling forging mechanism;

[0028] Forging pressure: 50~200MPa;

[0029] Forging mechanism moving speed: 1~5m / min;

[0030] Compression ratio: 5%~20%.

[0031] As a further improvement of the present invention, the parameters for the hot isostatic pressing process in step S3 are as follows:

[0032] Pressure: 100~150MPa;

[0033] Temperature: 1000~1200℃;

[0034] Insulation time: 2-4 hours;

[0035] Heating / cooling rate: 3-10℃ / min.

[0036] As a further improvement of the present invention, the parameters for high-temperature homogenization annealing in step S4 are as follows:

[0037] Processing environment: Vacuum level better than 5×10⁻²Pa, it is recommended to reach 1×10⁻³Pa or higher;

[0038] Temperature: 900~1110℃;

[0039] Insulation time: 1-3 hours;

[0040] Cooling method: furnace cooling or controlled rate cooling.

[0041] As a further improvement of the present invention, in S4, the parameters of the solution treatment are: temperature 800~1000℃, holding time 2~4 hours, and cooling method is oil quenching, gas quenching or water quenching.

[0042] As a further improvement of the present invention, in S4, the parameters of the aging treatment are: temperature 600~700℃, holding time 8~16 hours, and cooling method is air cooling or furnace cooling.

[0043] As a further improvement to the present invention, the specific steps include:

[0044] S1. Arc-fed powder additive manufacturing process: High-temperature alloy powder is deposited in a gradient ratio using a dual-channel powder feeding system, specifically as follows:

[0045] Additive manufacturing in the core area: Set the powder feeding rate of channel one to 2.5-4.0 m / min, and set the powder feeding rate of channel two to 0.5-1.5 m / min or 0 m / min;

[0046] Additive manufacturing in the transition zone: As the additive manufacturing path moves from the center of the disc to the edge of the disc, the powder feeding rate of channel one gradually decreases, while the powder feeding rate of channel two gradually increases.

[0047] Additive manufacturing in the disk edge area: Set the powder feeding rate of channel one to 0.5-1.5 m / min or 0 m / min, and set the powder feeding rate of channel two to 2.5-4.0 m / min;

[0048] The general parameters of the electric arc powder feeding additive manufacturing process are as follows:

[0049] Powder feeding speed in the mixing channel: 1~5m / min;

[0050] Arc current: 100~300A;

[0051] Arc voltage: 15~25V;

[0052] Deposition layer thickness: 0.5~2mm;

[0053] Inter-floor dwell time: 10~30s;

[0054] Protective atmosphere: high-purity Ar gas, flow rate 10-25 L / min, temperature controlled at -15~0℃;

[0055] S2. Synchronous micro-forging process: Mechanical deformation is applied to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. Specifically:

[0056] Forging timing: Immediately after each or several layers of material have solidified and are at a high temperature of 800-1150℃;

[0057] Forging method: The new deposited layer is subjected to unidirectional or multidirectional dynamic extrusion or rolling through a micro-rolling forging mechanism;

[0058] Forging pressure: 50~200MPa;

[0059] Forging mechanism moving speed: 1~5m / min;

[0060] Compression ratio: 5%~20%;

[0061] S3. Hot Isostatic Pressing Heat Treatment Process: The turbine disk blanks that have undergone additive manufacturing and simultaneous micro-forging are subjected to hot isostatic pressing treatment. The specific parameters are as follows:

[0062] Pressure: 100~150MPa;

[0063] Temperature: 1000~1200℃;

[0064] Insulation time: 2-4 hours;

[0065] Heating / cooling rate: 3-10℃ / min;

[0066] S4. Homogenization treatment: The billet after hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The specific parameters are as follows:

[0067] Processing environment: Vacuum level better than 5×10⁻²Pa, it is recommended to reach 1×10⁻³Pa or higher;

[0068] Temperature: 900~1110℃;

[0069] Insulation time: 1-3 hours;

[0070] Cooling method: furnace cooling or controlled-rate cooling;

[0071] S5. Solution treatment + aging heat treatment process: In a vacuum furnace with a vacuum degree ≤1×10⁻³Pa, the homogenized billet undergoes standard solution treatment and aging treatment to obtain a turbine disk blank, specifically:

[0072] Solution treatment: Temperature 800~1000℃, holding time 2~4 hours, cooling method is oil quenching, gas quenching or water quenching;

[0073] Aging treatment: temperature 600~700℃, holding time 8~16 hours, cooling method is air cooling or furnace cooling.

[0074] The present invention has the following beneficial effects:

[0075] This invention provides an application of a dual-channel powder feeding process in the preparation of turbine disk blanks for aero-engines. By combining gradient proportioning deposition, synchronous micro-forging process, cryogenic protective atmosphere and heat treatment process through a dual-channel powder feeding system, the technical problem of insufficient performance of turbine disks prepared by traditional processes is solved.

[0076] (1) The dual-channel powder feeding system combined with synchronous micro-forging process adopted in this invention achieves effective grain refinement and microstructure optimization. By mechanically deforming and breaking the cast dendrites, the recrystallization process is promoted, forming a fine and uniform grain structure, increasing the grain boundary area, effectively hindering dislocation movement, and improving the material strength. Experimental data show that the room temperature tensile strength and yield strength of Example 1 using this process are increased by about 12% and 15% respectively compared with Comparative Example 1, and the high temperature tensile strength and yield strength are increased by about 14% and 18% respectively.

[0077] (2) The dual-channel powder feeding system of the present invention realizes the gradient ratio deposition of two high-temperature alloys, forming a compositional gradient distribution in different parts of the turbine disk, giving full play to the complementary advantages of the two alloys. The gradient transition design avoids abrupt changes in interface composition, reduces interface stress concentration, and improves overall performance. Experiments show that, compared with Comparative Example 2, the creep rupture life of Example 1 under the conditions of 650℃ / 650MPa and 760℃ / 450MPa is increased by 33% and 50%, respectively, the fatigue life is increased by 39% and 50%, the crack propagation rate is reduced by 22%, and the thermal fatigue life is increased by 42%.

[0078] (3) The present invention employs a low-temperature protective atmosphere and a high-vacuum treatment environment, which effectively inhibits the oxidation reaction during the material preparation process. By reducing the oxygen partial pressure and active oxygen content in the environment, the initial oxide content inside the material is reduced, thereby improving the purity and oxidation resistance of the material. Experimental data show that the oxidation weight gain of Example 1 at 900℃ / 100h is about 28% lower than that of Comparative Example 1 and about 63% lower than that of Comparative Example 3.

[0079] (4) This invention employs a combination of heat treatment processes including hot isostatic pressing, homogenization, and solution treatment plus aging, which optimizes the microstructure and phase composition of the material. In particular, by controlling the size, morphology, and distribution of the γ′ phase, the thermal stability and high-temperature performance of the material are improved. Experiments show that the hardness of Example 1 decreased by about 5% after heat exposure at 900℃ for 500h, while that of Comparative Example 1 decreased by about 9%, and that of Comparative Example 3 decreased by about 12%.

[0080] (5) Through the synergistic effect of the above-mentioned processes, the present invention achieves a comprehensive improvement in the overall performance of turbine disk materials. Compared with Comparative Example 1, Example 1 shows an increase of 78% and 80% in creep rupture life, an increase of 67% and 80% in fatigue life, a decrease of 30% in crack propagation rate, and an increase of 63% in thermal fatigue life; compared with Comparative Example 3, it shows an increase of 100% and 112% in creep rupture life, an increase of 92% and 125% in fatigue life, a decrease of 36% in crack propagation rate, and an increase of 77% in thermal fatigue life.

[0081] (6) By improving the key properties of turbine disk materials such as high temperature strength, fatigue performance, crack propagation resistance, thermal fatigue life and oxidation resistance, this invention significantly improves the reliability, safety and service life of aero-engine turbine disks. At the same time, it provides technical support for the weight reduction design of turbine disks and the improvement of engine thrust-to-weight ratio, and has important engineering application value. Attached Figure Description

[0082] Figure 1 This is a schematic diagram of the synchronous micro-forging process using a dual-channel powder feeding process in Example 1.

[0083] Figure 2This is a schematic diagram of the dual-channel powder feeding system in Example 1, wherein powder feeding port 1 is channel one, powder feeding port 2 is channel two, and the powder feeding port is a powder feeding channel for mixing powder.

[0084] Figure 3 This is a schematic diagram of the powder feeding starting point and powder feeding direction in Example 1, wherein the powder feeding starting point is the center of the disk, and the powder feeding direction is counterclockwise.

[0085] Figure 4 This is a schematic diagram of the micro-rolling and forging mechanism in Example 1. Detailed Implementation

[0086] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0087] Example 1: A turbine disk blank was prepared using a dual-channel powder feeding process (see schematic diagram of the dual-channel powder feeding process and micro-forging process in this example). Figure 1 (As shown).

[0088] First, an arc-feeding additive manufacturing process is performed, where high-temperature alloy powder is fed through a dual-channel powder feeding system (see schematic diagram). Figure 2 Gradient-ratio deposition was performed (as shown). Channel 1 used GH4169 high-temperature alloy powder with a particle size of 45-105 μm, and Channel 2 used GH4738 high-temperature alloy powder with a particle size of 53-150 μm. During additive manufacturing in the disk core region, the powder feeding rate for Channel 1 was set to 3.5 m / min, and the powder feeding rate for Channel 2 was set to 0.8 m / min. During additive manufacturing in the transition region, the powder feeding rate was adjusted as the additive manufacturing path moved from the disk core to the disk edge (see schematic diagram of powder feeding start point and direction). Figure 3 As shown in the figure, the powder feeding rate of channel one gradually decreases to 1.5 m / min, and the powder feeding rate of channel two gradually increases to 2.8 m / min; when additive manufacturing in the disk edge region, the powder feeding rate of channel one is set to 0.8 m / min, and the powder feeding rate of channel two is set to 3.5 m / min. The general parameters of the arc powder feeding additive manufacturing process are: powder feeding speed of the mixed powder channel is 4.3 m / min, arc current is 180 A, arc voltage is 20 V, deposition layer thickness is 1.2 mm, interlayer residence time is 15 s, the protective atmosphere is high-purity Ar gas with a flow rate of 18 L / min, and the temperature is controlled at -10℃.

[0089] Subsequently, a synchronous micro-forging process is performed, applying mechanical deformation to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. The forging is initiated immediately when each layer of material has solidified and is at a high temperature of 950°C. The forging method utilizes a micro-rolling forging mechanism (see schematic diagram). Figure 4 As shown, a bidirectional dynamic extrusion is applied to the new deposited layer. The forging pressure is 120 MPa, the forging mechanism moving speed is 3 m / min, and the reduction rate is 12%.

[0090] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 125 MPa, temperature of 1100℃, holding time of 3 hours, and heating and cooling rate of 5℃ / min.

[0091] Then, homogenization treatment is carried out. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The treatment environment is a vacuum degree of 1×10⁻³Pa, a temperature of 1050℃, a holding time of 2 hours, and a controlled rate cooling method with a cooling rate of 3℃ / min.

[0092] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 1×10⁻³Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 950℃, the holding time is 3 hours, and the cooling method is oil quenching; the aging treatment temperature is 650℃, the holding time is 12 hours, and the cooling method is air cooling, to obtain the turbine disk blank.

[0093] Example 2: A turbine disk blank was prepared by applying a dual-channel powder feeding process.

[0094] First, an arc-feed additive manufacturing process is performed. High-temperature alloy powder is deposited in a gradient ratio using a dual-channel powder feeding system. Channel 1 uses GH4169 high-temperature alloy powder with a particle size of 40-100 μm, while Channel 2 uses GH4738 high-temperature alloy powder with a particle size of 50-145 μm. During additive manufacturing in the disk center region, the powder feeding rate for Channel 1 is set to 2.8 m / min, and the rate for Channel 2 is set to 0.5 m / min. During additive manufacturing in the transition region, as the additive path moves from the disk center to the disk edge, the powder feeding rate for Channel 1 gradually decreases to 1.2 m / min, while the rate for Channel 2 gradually increases to 2.1 m / min. During additive manufacturing in the disk edge region, the powder feeding rate for Channel 1 is set to 0.5 m / min, and the rate for Channel 2 is set to 2.8 m / min. The general parameters for the electric arc powder feeding additive manufacturing process are as follows: the powder feeding speed in the mixing powder channel is 3.3 m / min, the arc current is 150 A, the arc voltage is 18 V, the deposition layer thickness is 1.0 mm, the interlayer residence time is 20 s, the protective atmosphere is high-purity Ar gas with a flow rate of 15 L / min, and the temperature is controlled at -12 ℃.

[0095] Subsequently, a synchronous micro-forging process is carried out, in which mechanical deformation is applied to the newly deposited material layer that is in a high-temperature plastic state while the material is being deposited. The forging is carried out immediately after every two layers of material have solidified and are at a high temperature of 900°C. The forging method is to apply unidirectional dynamic rolling pressure to the newly deposited layer through a micro-rolling forging mechanism. The forging pressure is 100 MPa, the moving speed of the forging mechanism is 2 m / min, and the reduction rate is 10%.

[0096] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 110 MPa, temperature of 1050 ℃, holding time of 2.5 hours, and heating and cooling rate of 4 ℃ / min.

[0097] Then, homogenization treatment is carried out. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The treatment environment is a vacuum degree of 2×10⁻³Pa, a temperature of 1000℃, a holding time of 1.5 hours, and furnace cooling is used.

[0098] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 1×10⁻³Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 900℃, the holding time is 2.5 hours, and the cooling method is gas quenching; the aging treatment temperature is 630℃, the holding time is 10 hours, and the cooling method is furnace cooling, to obtain the turbine disk blank.

[0099] Example 3: A turbine disk blank was prepared by applying a dual-channel powder feeding process.

[0100] First, an arc-feed additive manufacturing process is performed. High-temperature alloy powder is deposited using a gradient ratio through a dual-channel powder feeding system. Channel 1 uses GH4169 high-temperature alloy powder with a particle size of 50-110 μm, while Channel 2 uses GH4738 high-temperature alloy powder with a particle size of 55-155 μm. During additive manufacturing in the disk center region, the powder feeding rate for Channel 1 is set to 4.0 m / min, and the powder feeding rate for Channel 2 is set to 0 m / min. During additive manufacturing in the transition region, as the additive path moves from the disk center to the disk edge, the powder feeding rate for Channel 1 gradually decreases to 2.0 m / min, while the powder feeding rate for Channel 2 gradually increases to 2.0 m / min. During additive manufacturing in the disk edge region, the powder feeding rate for Channel 1 is set to 0 m / min, and the powder feeding rate for Channel 2 is set to 4.0 m / min. The general parameters for the electric arc powder feeding additive manufacturing process are as follows: the powder feeding speed in the mixing powder channel is 4.0 m / min, the arc current is 200 A, the arc voltage is 22 V, the deposition layer thickness is 1.5 mm, the interlayer residence time is 25 s, the protective atmosphere is high-purity Ar gas with a flow rate of 20 L / min, and the temperature is controlled at -8℃.

[0101] Subsequently, a synchronous micro-forging process is carried out, in which mechanical deformation is applied to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. The forging is carried out immediately when each layer of material is solidified and at a high temperature of 1000℃. The forging method is to apply multi-directional dynamic extrusion to the newly deposited layer through a micro-rolling forging mechanism. The forging pressure is 150MPa, the forging mechanism moving speed is 4m / min, and the reduction rate is 15%.

[0102] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 140 MPa, temperature of 1150 ℃, holding time of 3.5 hours, and heating and cooling rate of 7 ℃ / min.

[0103] Then, a homogenization process is performed. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace under a vacuum environment of 5×10⁻⁻⁻⁶. 4 Pa, temperature is 1100℃, holding time is 2.5 hours, cooling method is controlled rate cooling, cooling rate is 5℃ / min.

[0104] Finally, a solution treatment followed by aging heat treatment is performed at a vacuum degree of 5×10⁻⁻⁻⁻⁻⁻⁻⁻⁵ ... 4 In a vacuum furnace of Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 980℃, the holding time is 3.5 hours, and the cooling method is oil quenching; the aging treatment temperature is 670℃, the holding time is 14 hours, and the cooling method is air cooling, to obtain turbine disk blank.

[0105] Example 4: A turbine disk blank was prepared by applying a dual-channel powder feeding process.

[0106] First, an arc-feed additive manufacturing process is performed. High-temperature alloy powder is deposited in a gradient ratio using a dual-channel powder feeding system. Channel 1 uses GH4169 high-temperature alloy powder with a particle size of 48-108 μm, while Channel 2 uses GH4738 high-temperature alloy powder with a particle size of 52-148 μm. During additive manufacturing in the disk center region, the powder feeding rate for Channel 1 is set to 2.5 m / min, and the rate for Channel 2 is set to 1.0 m / min. During additive manufacturing in the transition region, as the additive path moves from the disk center to the disk edge, the powder feeding rate for Channel 1 gradually decreases to 1.8 m / min, while the rate for Channel 2 gradually increases to 1.8 m / min. During additive manufacturing in the disk edge region, the powder feeding rate for Channel 1 is set to 1.0 m / min, and the rate for Channel 2 is set to 2.5 m / min. The general parameters for the electric arc powder feeding additive manufacturing process are as follows: the powder feeding speed in the mixing powder channel is 3.5 m / min, the arc current is 160 A, the arc voltage is 19 V, the deposition layer thickness is 0.8 mm, the interlayer residence time is 18 s, the protective atmosphere is high-purity Ar gas with a flow rate of 16 L / min, and the temperature is controlled at -15 ℃.

[0107] Subsequently, a synchronous micro-forging process is carried out, in which mechanical deformation is applied to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. The forging is carried out immediately after every 3 layers of material have solidified and are at a high temperature of 850°C. The forging method is to apply unidirectional dynamic extrusion to the newly deposited layer through a micro-rolling forging mechanism. The forging pressure is 80 MPa, the forging mechanism moving speed is 1.5 m / min, and the reduction rate is 8%.

[0108] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 105 MPa, temperature of 1020℃, holding time of 2 hours, and heating and cooling rate of 3.5℃ / min.

[0109] Then, homogenization treatment is carried out. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The treatment environment is a vacuum degree of 3×10⁻³Pa, a temperature of 950℃, a holding time of 1 hour, and furnace cooling is used.

[0110] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 3×10⁻³Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 850℃, the holding time is 2 hours, and the cooling method is gas quenching. The aging treatment temperature is 620℃, the holding time is 9 hours, and the cooling method is furnace cooling to obtain turbine disk blank.

[0111] Example 5: A turbine disk blank was prepared using a dual-channel powder feeding process.

[0112] First, an arc-feed additive manufacturing process is performed. High-temperature alloy powder is deposited using a gradient ratio through a dual-channel powder feeding system. Channel 1 uses GH4169 high-temperature alloy powder with a particle size of 42-102 μm, while Channel 2 uses GH4738 high-temperature alloy powder with a particle size of 54-152 μm. During additive manufacturing in the disk center region, the powder feeding rate for Channel 1 is set to 3.2 m / min, and the rate for Channel 2 is set to 1.5 m / min. During additive manufacturing in the transition region, as the additive path moves from the disk center to the disk edge, the powder feeding rate for Channel 1 gradually decreases to 2.3 m / min, while the rate for Channel 2 gradually increases to 2.4 m / min. During additive manufacturing in the disk edge region, the powder feeding rate for Channel 1 is set to 1.5 m / min, and the rate for Channel 2 is set to 3.2 m / min. The general parameters for the electric arc powder feeding additive manufacturing process are as follows: the powder feeding speed in the mixing powder channel is 4.7 m / min, the arc current is 250 A, the arc voltage is 23 V, the deposition layer thickness is 1.8 mm, the interlayer residence time is 30 s, the protective atmosphere is high-purity Ar gas with a flow rate of 22 L / min, and the temperature is controlled at -5 ℃.

[0113] Subsequently, a synchronous micro-forging process is carried out, in which mechanical deformation is applied to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. The forging is carried out immediately after every two layers of material have solidified and are at a high temperature of 1100°C. The forging method is to apply multi-directional dynamic rolling to the newly deposited layer through a micro-rolling forging mechanism. The forging pressure is 180 MPa, the moving speed of the forging mechanism is 4.5 m / min, and the reduction rate is 18%.

[0114] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 145 MPa, temperature of 1180℃, holding time of 4 hours, and heating and cooling rate of 9℃ / min.

[0115] Then, homogenization treatment is carried out. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The treatment environment is a vacuum degree of 1×10⁻³Pa, a temperature of 1080℃, a holding time of 3 hours, and a controlled rate cooling method with a cooling rate of 6℃ / min.

[0116] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 1×10⁻³Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 980℃, the holding time is 4 hours, and the cooling method is water quenching; the aging treatment temperature is 680℃, the holding time is 16 hours, and the cooling method is air cooling, to obtain the turbine disk blank.

[0117] Comparative Example 1: A turbine disk blank was prepared. Unlike Example 1, this comparative example did not undergo synchronous micro-forging process, but directly underwent hot isostatic pressing heat treatment process.

[0118] First, an arc-feed additive manufacturing process is performed. High-temperature alloy powder is deposited using a gradient ratio through a dual-channel powder feeding system. Channel 1 uses GH4169 high-temperature alloy powder with a particle size of 45-105 μm, while Channel 2 uses GH4738 high-temperature alloy powder with a particle size of 53-150 μm. During additive manufacturing in the disk center region, the powder feeding rate for Channel 1 is set to 3.5 m / min, and the rate for Channel 2 is set to 0.8 m / min. During additive manufacturing in the transition region, as the additive path moves from the disk center to the disk edge, the powder feeding rate for Channel 1 gradually decreases to 1.5 m / min, while the rate for Channel 2 gradually increases to 2.8 m / min. During additive manufacturing in the disk edge region, the powder feeding rate for Channel 1 is set to 0.8 m / min, and the rate for Channel 2 is set to 3.5 m / min. The general parameters for the electric arc powder feeding additive manufacturing process are as follows: the powder feeding speed in the mixing powder channel is 4.3 m / min, the arc current is 180 A, the arc voltage is 20 V, the deposition layer thickness is 1.2 mm, the interlayer residence time is 15 s, the protective atmosphere is high-purity Ar gas with a flow rate of 18 L / min, and the temperature is controlled at -10 ℃.

[0119] The additively manufactured turbine disk blank was subjected to hot isostatic pressing (HIP) with the following parameters: pressure 125 MPa, temperature 1100℃, holding time 3 hours, and heating / cooling rate 5℃ / min. Then, homogenization was performed. The HIP-treated blank was subjected to high-temperature homogenization annealing in a vacuum furnace at a vacuum level of 1×10⁻³ Pa, a temperature of 1050℃, a holding time of 2 hours, and controlled-rate cooling at a rate of 3℃ / min.

[0120] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 1×10⁻³Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 950℃, the holding time is 3 hours, and the cooling method is oil quenching; the aging treatment temperature is 650℃, the holding time is 12 hours, and the cooling method is air cooling, to obtain the turbine disk blank.

[0121] Comparative Example 2: A turbine disk blank was prepared. Unlike Example 1, the dual-channel powder feeding system was replaced with a single-channel powder feeding system.

[0122] First, an arc-feed additive manufacturing process was performed, depositing high-temperature alloy powder through a single-channel powder feeding system. A single type of GH4169 high-temperature alloy powder with a particle size of 45-105 μm was used. During the entire turbine disk additive manufacturing process, the powder feeding rate was set to 3.5 m / min. The general parameters for the arc-feed additive manufacturing process were: powder feeding speed 3.5 m / min, arc current 180 A, arc voltage 20 V, deposition layer thickness 1.2 mm, interlayer residence time 15 s, high-purity Ar gas at a flow rate of 18 L / min, and temperature controlled at -10℃.

[0123] Subsequently, a synchronous micro-forging process is carried out, in which mechanical deformation is applied to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. The forging is carried out immediately when each layer of material is solidified and at a high temperature of 950°C. The forging method is to apply bidirectional dynamic extrusion to the newly deposited layer through a micro-rolling forging mechanism. The forging pressure is 120 MPa, the forging mechanism moving speed is 3 m / min, and the reduction rate is 12%.

[0124] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 125 MPa, temperature of 1100℃, holding time of 3 hours, and heating and cooling rate of 5℃ / min.

[0125] Then, homogenization treatment is carried out. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The treatment environment is a vacuum degree of 1×10⁻³Pa, a temperature of 1050℃, a holding time of 2 hours, and a controlled rate cooling method with a cooling rate of 3℃ / min.

[0126] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 1×10⁻³Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 950℃, the holding time is 3 hours, and the cooling method is oil quenching; the aging treatment temperature is 650℃, the holding time is 12 hours, and the cooling method is air cooling, to obtain the turbine disk blank.

[0127] Comparative Example 3: A turbine disk blank was prepared. Compared with Example 1, Comparative Example 3 lacked the low-temperature protective atmosphere and high-vacuum processing environment.

[0128] First, an arc-feed additive manufacturing process is performed. High-temperature alloy powder is deposited using a gradient ratio through a dual-channel powder feeding system. Channel 1 uses GH4169 high-temperature alloy powder with a particle size of 45-105 μm, while Channel 2 uses GH4738 high-temperature alloy powder with a particle size of 53-150 μm. During additive manufacturing in the disk center region, the powder feeding rate for Channel 1 is set to 3.5 m / min, and the rate for Channel 2 is set to 0.8 m / min. During additive manufacturing in the transition region, as the additive path moves from the disk center to the disk edge, the powder feeding rate for Channel 1 gradually decreases to 1.5 m / min, while the rate for Channel 2 gradually increases to 2.8 m / min. During additive manufacturing in the disk edge region, the powder feeding rate for Channel 1 is set to 0.8 m / min, and the rate for Channel 2 is set to 3.5 m / min. The general parameters for the electric arc powder feeding additive manufacturing process are as follows: the powder feeding speed in the mixing powder channel is 4.3 m / min, the arc current is 180 A, the arc voltage is 20 V, the deposition layer thickness is 1.2 mm, the interlayer residence time is 15 s, the protective atmosphere is ordinary Ar gas with a purity of 99.5% with a flow rate of 18 L / min, and the temperature is 25 ℃.

[0129] Subsequently, a synchronous micro-forging process is carried out, in which mechanical deformation is applied to the newly deposited material layer in a high-temperature plastic state while the material is being deposited. The forging is carried out immediately when each layer of material is solidified and at a high temperature of 950°C. The forging method is to apply bidirectional dynamic extrusion to the newly deposited layer through a micro-rolling forging mechanism. The forging pressure is 120 MPa, the forging mechanism moving speed is 3 m / min, and the reduction rate is 12%.

[0130] Next, a hot isostatic pressing (HIP) heat treatment process is carried out on the turbine disk blank that has completed additive manufacturing and synchronous micro-forging. The specific parameters are: pressure of 125 MPa, temperature of 1100℃, holding time of 3 hours, and heating and cooling rate of 5℃ / min.

[0131] Then, homogenization treatment is carried out. The billet that has undergone hot isostatic pressing is subjected to high-temperature homogenization annealing in a vacuum furnace. The treatment environment is a vacuum degree of 1×10⁻²Pa, a temperature of 1050℃, a holding time of 2 hours, and a controlled rate cooling method with a cooling rate of 3℃ / min.

[0132] Finally, a solution treatment and aging heat treatment process is carried out. In a vacuum furnace with a vacuum degree of 1×10⁻²Pa, the homogenized billet is subjected to standard solution treatment and aging treatment. The solution treatment temperature is 950℃, the holding time is 3 hours, and the cooling method is oil quenching; the aging treatment temperature is 650℃, the holding time is 12 hours, and the cooling method is air cooling, to obtain the turbine disk blank.

[0133] Performance testing

[0134] Test Method 1, Microstructure Analysis: Metallographic specimens were prepared from the turbine disk samples of the examples and comparative examples, taking samples from the disk center, transition zone, and disk rim. First, the samples were cut into 10mm × 10mm × 5mm pieces, and then subjected to a standard metallographic preparation procedure: coarse grinding (120-1200 grit sandpaper sequentially), fine grinding (polishing with 1.0μm and 0.5μm diamond suspensions), ultrasonic cleaning (10 minutes each with acetone and ethanol), and drying (30 minutes in a 60℃ oven). Subsequently, an etching solution (10ml HNO3 + 30ml HCl + 40ml H2O) was used to etch the specimens at room temperature for 30–60 seconds, followed by ultrasonic cleaning and drying. Grain morphology and size were observed using a ZEISS Axio Imager M2m metallurgical microscope at magnifications of 100×, 500×, and 1000×. Grain size statistical analysis was performed using Image-Pro Plus 6.0 software. Ten fields of view were randomly selected for each sample, and at least 200 grains were measured. Microstructure characteristics were observed using a FEI Quanta 650 FEG scanning electron microscope (SEM) with an accelerating voltage of 20 kV and a working distance of 10 mm. The morphology and distribution of precipitated phases were observed using a JEOL JEM-2100F transmission electron microscope (TEM). Dual-jet electrolytic polishing was used to prepare the thin film samples. The electrolyte was 10% perchloric acid + 90% ethanol, the temperature was -30℃, the voltage was 20 V, the current was 30 mA, and the polishing time was 60–90 seconds.

[0135] Test method 2: Mechanical property test method.

[0136] Tensile property testing: Standard tensile specimens were fabricated from the turbine disk center, transition zone, and rim areas prepared according to GB / T 228.1-2010 standard. The gauge length of the specimens was 25 mm and the diameter was 5 mm. Tensile tests were conducted at room temperature (25℃), medium temperature (650℃), and high temperature (850℃) using an MTS810 material testing system. For the high-temperature test, the specimen was first heated to the target temperature and held for 30 minutes to ensure uniform temperature. Then, the tensile test was performed at a rate of 1 mm / min until the specimen fractured. The tensile strength (σb), yield strength (σ0.2), elongation (δ), and reduction of area (ψ) were recorded. Three parallel samples were tested under each condition, and the average value was taken as the final result.

[0137] Creep performance testing: Standard creep test specimens were fabricated according to GB / T 2039-2012 standard, from the turbine disk center, transition zone, and rim areas prepared in the examples and comparative examples. The gauge length of the specimens was 25 mm, and the diameter was 5 mm. Creep performance testing was conducted using an RDL-50 high-temperature creep testing machine at test temperatures of 650℃ and 760℃, and stress levels of 650 MPa and 450 MPa, respectively. The fracture time and elongation at break were recorded. Three parallel samples were tested under each condition, and the average value was taken as the final result.

[0138] Fatigue performance testing: Standard high-cycle fatigue specimens were fabricated from the turbine disk core, transition zone, and rim areas prepared according to GB / T 3075-2008 standard. The gauge length of the specimens was 12 mm and the diameter was 6 mm. High-cycle fatigue tests were conducted using an MTS810 fatigue testing system at room temperature (25℃) and high temperature (650℃) with axial loading, a stress ratio R=0.1, frequencies of 20 Hz (room temperature) and 10 Hz (high temperature), and a maximum stress level of 800 MPa. The number of cycles at fracture was recorded. Five parallel specimens were tested under each condition, and the logarithmic mean was taken as the final result.

[0139] Crack propagation rate testing: CT specimens, with a thickness of 12.5 mm, were fabricated from the turbine disk core, transition zone, and rim regions prepared according to GB / T 6398-2000 standard. Crack propagation rates at room temperature (25℃) and high temperature (650℃) were tested using an MTS 810 fatigue crack propagation testing system, employing a constant amplitude loading method with a stress ratio R=0.1 and frequencies of 10 Hz (room temperature) and 5 Hz (high temperature). Crack length was monitored in real-time using the DC potential drop method. Based on the test data, the crack propagation rate (da / dN) was calculated for different stress intensity factor ranges (ΔK).

[0140] Test Method 3: High Temperature Performance Test Method

[0141] Thermal fatigue performance testing: Thermal fatigue specimens with dimensions of 100mm × 10mm × 3mm were machined from the turbine disk rim region prepared in the examples and comparative examples. Thermal fatigue testing was conducted using a self-developed thermal fatigue testing device. The temperature cycling range was 100-750℃, the heating rate was 50℃ / s, the cooling rate was 30℃ / s, the high-temperature holding time was 60s, and the low-temperature holding time was 30s. Surface cracking was checked every 100 cycles, and crack length and density were observed and recorded using an optical microscope. The test continued until a through crack exceeding 2mm in length appeared on the sample surface; the number of cycles at this point was recorded as the thermal fatigue life.

[0142] Oxidation resistance test: Oxidized samples with dimensions of 20 mm × 10 mm × 2 mm were processed from the rim region of the turbine disks prepared in the examples and comparative examples. Isothermal oxidation tests were conducted using a high-temperature box furnace at 900 °C for 100 hours. Samples were removed every 10 hours, cooled to room temperature, and their mass was measured using a precision electronic balance (accuracy 0.01 mg). Based on the test data, the weight gain per unit area was calculated, and an oxidation kinetic curve was fitted. After the test, the morphology and cross-sectional structure of the oxide film on the sample surface were observed using SEM, and the oxide composition was analyzed using energy dispersive spectroscopy (EDS).

[0143] Thermal stability test: Turbine disk samples prepared from the examples and comparative examples were subjected to long-term heat exposure at 900°C (500 hours), and then the changes in hardness and microstructure before and after heat exposure were measured. The Vickers hardness of the samples was measured using an HVS-1000 digital microhardness tester with a load of 1 kg and a holding time of 15 s. Ten points were randomly selected for measurement on each sample, and the average value was taken.

[0144] Test Results Table

[0145] Table 1. Grain size statistics (μm)

[0146] Sample number The center area Transition area Plate edge area Example 1 35±3 38±4 42±3 Example 2 38±4 40±3 45±4 Example 3 32±2 35±3 40±3 Example 4 40±3 42±4 47±4 Example 5 30±2 33±3 38±2 Comparative Example 1 48±5 52±6 58±5 Comparative Example 2 36±4 45±5 55±6 Comparative Example 3 42±4 45±5 50±5

[0147] Table 2. Statistical results of γ' phase precipitates

[0148] Sample number The center area Plate edge area Size (nm) Volume fraction (%) Size (nm) Volume fraction (%) Example 1 25±5 12±2 45±8 25±3 Example 2 28±6 10±2 48±7 23±3 Example 3 22±4 14±2 42±6 28±3 Example 4 30±6 9±2 50±8 22±3 Example 5 20±4 15±2 40±5 30±3 Comparative Example 1 32±8 11±3 55±10 22±4 Comparative Example 2 26±5 12±2 28±6 13±2 Comparative Example 3 35±8 10±3 60±12 18±4

[0149] Table 3. Room Temperature Tensile Properties Test Data

[0150] Sample number Tensile strength (MPa) Yield strength (MPa) Elongation (%) Reduction of area (%) Example 1 1320±20 1050±15 22±2 25±2 Example 2 1280±25 1020±20 24±2 28±3 Example 3 1350±15 1080±15 20±2 23±2 Example 4 1250±25 980±20 26±3 30±3 Example 5 1380±15 1100±10 19±2 22±2 Comparative Example 1 1160±30 890±25 18±3 20±3 Comparative Example 2 1220±25 950±20 21±2 24±2 Comparative Example 3 1200±30 920±25 16±3 18±3

[0151] Table 4. Tensile property test data at 650℃

[0152] Sample number Tensile strength (MPa) Yield strength (MPa) Elongation (%) Reduction of area (%) Example 1 1050±20 850±15 18±2 20±2 Example 2 1020±25 820±20 20±2 22±2 Example 3 1080±15 880±15 16±2 18±2 Example 4 980±25 780±20 22±2 24±2 Example 5 1100±15 900±10 15±2 17±2 Comparative Example 1 920±30 720±25 14±3 16±3 Comparative Example 2 950±25 760±20 17±2 19±2 Comparative Example 3 880±30 700±25 12±3 14±3

[0153] Table 5. Durability Test Data at 650℃ / 650MPa

[0154] Sample number Fragmentation time (h) Elongation at break (%) Example 1 320±20 15±2 Example 2 280±25 18±2 Example 3 350±15 13±2 Example 4 250±25 20±2 Example 5 380±15 12±2 Comparative Example 1 180±30 22±3 Comparative Example 2 240±25 16±2 Comparative Example 3 160±30 25±3

[0155] Table 6.760℃ / 450MPa Durability Test Data

[0156] Sample number Fragmentation time (h) Elongation at break (%) Example 1 180±15 12±2 Example 2 160±20 14±2 Example 3 200±10 10±1 Example 4 140±20 16±2 Example 5 220±10 9±1 Comparative Example 1 100±25 18±3 Comparative Example 2 120±20 15±2 Comparative Example 3 85±25 20±3

[0157] Table 7. High-cycle fatigue test data at room temperature (800MPa, R=0.1)

[0158] Sample number Fatigue life (number of cycles) Example 1 <![CDATA[2.5×10 5 ±0.3×10 5 ]]> Example 2 <![CDATA[2.2×10 5 ±0.4×10 5 ]]> Example 3 <![CDATA[2.8×10 5 ±0.2×10 5 ]]> Example 4 <![CDATA[2.0×10 5 ±0.4×10 5 <!-- 12 -->]]> Example 5 <![CDATA[3.0×10 5 ±0.2×10 5 ]]> Comparative Example 1 <![CDATA[1.5×10 5 ±0.5×10 5 ]]> Comparative Example 2 <![CDATA[1.8×10 5 ±0.4×10 5 ]]> Comparative Example 3 <![CDATA[1.3×10 5 ±0.5×10 5 ]]>

[0159] Table 8. High-cycle fatigue test data at 650℃ (800MPa, R=0.1)

[0160] Sample number Fatigue life (number of cycles) Example 1 <![CDATA[1.8×10 5 ±0.2×10 5 ]]> Example 2 <![CDATA[1.6×10 5 ±0.3×10 5 ]]> Example 3 <![CDATA[2.0×10 5 ±0.2×10 5 ]]> Example 4 <![CDATA[1.4×10 5 ±0.3×10 5 ]]> Example 5 <![CDATA[2.2×10 5 ±0.1×10 5 ]]> Comparative Example 1 <![CDATA[1.0×10 5 ±0.4×10 5 ]]> Comparative Example 2 <![CDATA[1.2×10 5 ±0.3×10 5 ]]> Comparative Example 3 <![CDATA[0.8×10 5 ±0.4×10 5 ]]>

[0161] Table 9. Crack propagation rate test data at 650℃ (ΔK=20MPa·m^(1 / 2))

[0162] Sample number Crack propagation rate (m / cycle) Example 1 <![CDATA[3.5×10⁻ 8 ±0.3×10⁻ 8 ]]> Example 2 <![CDATA[3.8×10⁻ 8 ±0.4×10⁻ 8 ]]> Example 3 <![CDATA[3.2×10⁻ 8 ±0.2×10⁻ 8 ]]> Example 4 <![CDATA[4.0×10⁻ 8 ±0.4×10⁻ 8 ]]> Example 5 <![CDATA[3.0×10⁻ 8 ±0.2×10⁻ 8 ]]> Comparative Example 1 <![CDATA[5.0×10⁻ 8 ±0.5×10⁻ 8 ]]> Comparative Example 2 <![CDATA[4.5×10⁻ 8 ±0.4×10⁻ 8 ]]> Comparative Example 3 <![CDATA[5.5×10⁻ 8 ±0.5×10⁻ 8 ]]>

[0163] Table 10. Thermal fatigue life test data (100-750℃ cycle)

[0164] Sample number Thermal fatigue life (number of cycles) Example 1 850±50 Example 2 780±60 Example 3 920±40 Example 4 720±60 Example 5 980±40 Comparative Example 1 520±80 Comparative Example 2 600±70 Comparative Example 3 480±80

[0165] Table 11. Oxidative weight gain test data at 900℃ / 100h

[0166] Sample number Oxidative weight gain (mg / cm²) Example 1 1.8±0.2 Example 2 2.0±0.2 Example 3 1.6±0.1 Example 4 2.2±0.2 Example 5 1.5±0.1 Comparative Example 1 2.5±0.3 Comparative Example 2 2.3±0.2 Comparative Example 3 4.8±0.4

[0167] Table 12. Hardness change rate data after 900℃ / 500h heat exposure (%)

[0168] Sample number Hardness change rate (%) Example 1 -5±1 Example 2 -6±1 Example 3 -4±1 Example 4 -7±1 Example 5 -3±1 Comparative Example 1 -9±2 Comparative Example 2 -8±2 Comparative Example 3 -12±2

[0169] Data Analysis

[0170] As shown in Table 1, the grain size of Examples 1-5 is significantly smaller than that of Comparative Examples 1-3, especially Comparative Example 1, whose grain size is approximately 35% smaller than that of Example 1. This is because the examples employed a simultaneous micro-forging process, which applied mechanical deformation to the newly deposited layer while the material was being deposited, promoting dynamic recrystallization and refining the grains. This grain refinement not only improved the strength of the material but also its plasticity and toughness. Comparative Example 1, lacking the simultaneous micro-forging process, resulted in coarse grains and an uneven microstructure. Although Comparative Example 2 also employed a simultaneous micro-forging process, the lack of a dual-channel powder feeding system for gradient proportioning deposition led to coarser grains in the disk edge region. Although Comparative Example 3 employed both a dual-channel powder feeding system and a simultaneous micro-forging process, the lack of a low-temperature protective atmosphere and a high-vacuum treatment environment resulted in increased oxidation of the material, increased oxides at grain boundaries, hindered and uneven grain growth, and a more uneven grain size distribution.

[0171] As can be seen from Table 2, the volume fraction of γ' phase precipitates in the disk edge region of Examples 1-5 is significantly higher than that of Comparative Example 2. This is because the examples used a dual-channel powder feeding system for gradient ratio deposition, which proves that the dual-channel powder feeding system used in this invention can effectively control the alloy composition and microstructure of different regions of the turbine disk. The disk edge region has a higher GH4738 alloy composition, and the volume fraction of γ' phase precipitates in GH4738 alloy is higher than that in GH4169 alloy, which is beneficial to improving the high-temperature performance of the disk edge region. Although Comparative Example 1 also used a dual-channel powder feeding system, the lack of a synchronous micro-forging process resulted in larger and unevenly distributed γ' phase precipitates with a slightly lower volume fraction than in Example 1. Comparative Example 2, lacking a dual-channel powder feeding system for gradient deposition, resulted in a lower volume fraction of γ' phase precipitates in the disk edge region and insufficient high-temperature performance. Although Comparative Example 3 used a dual-channel powder feeding system and a synchronous micro-forging process, the lack of a low-temperature protective atmosphere and a high-vacuum treatment environment led to increased material oxidation, inhibited γ' phase precipitation, a lower volume fraction than in Example 1, and larger and unevenly distributed γ' phases.

[0172] As shown in Table 3, the room temperature tensile properties of Examples 1-5 are significantly better than those of Comparative Examples 1-3, fully demonstrating that the synchronous micro-forging process and the gradient proportioning deposition using the dual-channel powder feeding system employed in this invention can effectively improve the strength of the material. The tensile strength and yield strength of Example 1 are approximately 12% and 15% higher than those of Comparative Example 1, respectively. This is because Example 1 employs a synchronous micro-forging process, which refines the grains and improves the material's strength. The elongation and reduction of area of ​​Example 1 are also higher than those of Comparative Example 1, indicating that the material's plasticity has also been improved. Although Comparative Example 2 also employs a synchronous micro-forging process, the lack of a dual-channel powder feeding system for gradient proportioning deposition leads to uneven material properties, resulting in overall performance lower than Example 1. Although Comparative Example 3 employs a dual-channel powder feeding system and a synchronous micro-forging process, the lack of a low-temperature protective atmosphere and a high-vacuum treatment environment leads to increased oxidation and internal oxide content, reducing the material's strength and plasticity.

[0173] As can be seen from Table 4, the high-temperature tensile properties of Examples 1-5 are significantly better than those of Comparative Examples 1-3. The high-temperature tensile strength and yield strength of Example 1 are about 14% and 18% higher than those of Comparative Example 1, respectively. This is mainly because Example 1 adopted a synchronous micro-forging process and a dual-channel powder feeding system for gradient proportioning deposition, which optimized the microstructure of the material and improved the high-temperature strength.

[0174] As can be seen from Tables 5 and 6, the creep resistance of Examples 1-5 is significantly better than that of Comparative Examples 1-3. The fracture time of Example 1 under the conditions of 650℃ / 650MPa and 760℃ / 450MPa is about 78% and 80% longer than that of Comparative Example 1, respectively. This is because Example 1 adopted a synchronous micro-forging process, which refined the grains, reduced grain boundary slip, and improved the creep resistance of the material. At the same time, the gradient ratio deposition of the dual-channel powder feeding system resulted in a higher GH4738 alloy composition in the disk edge region. The high-temperature performance of GH4738 alloy is better than that of GH4169 alloy, which further improved the creep resistance of the material. Although Comparative Example 2 also adopted a synchronous micro-forging process, the lack of a dual-channel powder feeding system for gradient ratio deposition led to insufficient high-temperature performance in the disk edge region, resulting in creep resistance lower than that of Example 1. Although Comparative Example 3 adopted a dual-channel powder feeding system and a synchronous micro-forging process, the lack of a low-temperature protective atmosphere and a high-vacuum treatment environment led to increased oxidation of the material and an increase in internal oxides, which reduced the creep resistance of the material.

[0175] As can be seen from Tables 7 and 8, the fatigue performance of Examples 1-5 is significantly better than that of Comparative Examples 1-3. The room temperature and 650°C high-cycle fatigue lives of Example 1 are approximately 67% and 80% longer than those of Comparative Example 1, respectively. This is because Example 1 employs a synchronous micro-forging process, which refines the grains, reduces microcrack initiation points, and improves the fatigue resistance of the material. Simultaneously, the low-temperature protective atmosphere and high-vacuum treatment environment reduce oxides and other defects within the material, further enhancing its fatigue performance.

[0176] As can be seen from Table 9, the crack propagation rates of Examples 1-5 are significantly lower than those of Comparative Examples 1-3. The crack propagation rate at 650℃ in Example 1 is about 30% lower than that in Comparative Example 1. This is because Example 1 uses a synchronous micro-forging process and a dual-channel powder feeding system for gradient proportioning deposition, which optimizes the microstructure of the material, improves the fracture toughness of the material, and reduces the crack propagation rate.

[0177] As can be seen from Table 10, the thermal fatigue life of Examples 1-5 is significantly longer than that of Comparative Examples 1-3. The thermal fatigue life of Example 1 is about 63% longer than that of Comparative Example 1. This is because Example 1 uses a synchronous micro-forging process and a dual-channel powder feeding system for gradient proportioning deposition, which optimizes the microstructure of the material and improves its thermal fatigue resistance. At the same time, the low-temperature protective atmosphere and high-vacuum treatment environment reduce oxides and other defects inside the material, further improving the material's thermal fatigue performance. Turbine disks are frequently subjected to thermal cycling loads during operation, and improving the thermal fatigue life is of great significance for the service life and safety of turbine disks.

[0178] As shown in Table 11, the oxidation resistance of Examples 1-5 is significantly better than that of Comparative Examples 1-3, especially Comparative Example 3. The oxidation weight gain of Example 1 at 900℃ / 100h is approximately 28% lower than that of Comparative Example 1 and approximately 63% lower than that of Comparative Example 3. This is because Example 1 uses a low-temperature protective atmosphere and a high-vacuum treatment environment, which reduces the initial oxides inside the material and improves its oxidation resistance. This fully demonstrates that the low-temperature protective atmosphere and high-vacuum treatment environment used in this invention can effectively reduce the initial oxides inside the material and improve its oxidation resistance. Comparative Example 3, lacking a low-temperature protective atmosphere and a high-vacuum treatment environment, has a higher degree of initial oxidation inside the material, resulting in a significant decrease in oxidation resistance.

[0179] As shown in Table 12, the thermal stability of Examples 1-5 is significantly better than that of Comparative Examples 1-3. After 900℃ / 500h heat exposure, the hardness of Example 1 decreased by approximately 5%, while that of Comparative Example 1 decreased by approximately 9%, and that of Comparative Example 3 by approximately 12%, indicating that Example 1 has better thermal stability. This is because Example 1 employed a synchronous micro-forging process and a dual-channel powder feeding system for gradient proportioning deposition, optimizing the microstructure of the material, particularly the size, morphology, and distribution of the γ' phase, thus improving the material's thermal stability. Simultaneously, the low-temperature protective atmosphere and high-vacuum treatment environment reduced oxides and other defects within the material, further enhancing its thermal stability. This fully demonstrates that the process employed in this invention can effectively improve the thermal stability of materials. Turbine disks are prone to microstructural evolution under long-term high-temperature operating conditions, and improved thermal stability is crucial for maintaining the long-term performance of turbine disks.

[0180] In summary, Examples 1-5 exhibited significant advantages over Comparative Examples 1-3 in terms of microstructure, mechanical properties, and high-temperature performance. Specifically, compared to Comparative Example 1, Example 1 showed a 12% increase in room temperature tensile strength and a 14% increase in high-temperature tensile strength, a 78% increase in creep rupture life and an 80% increase in fatigue life, a 67% increase in crack propagation rate and an 80% increase in thermal fatigue life, a 30% decrease in crack propagation rate, a 63% increase in thermal fatigue life, a 28% decrease in oxidative weight gain, and a 4 percentage point increase in thermal stability. Compared to Comparative Example 2, Example 1 showed a 33% increase in creep rupture life and a 50% increase in fatigue life, a 39% increase in fatigue life, a 22% decrease in crack propagation rate, a 42% increase in thermal fatigue life, a 22% decrease in oxidative weight gain, and a 3 percentage point increase in thermal stability. Compared to Comparative Example 3, Example 1 showed a 10% increase in room temperature tensile strength and a 19% increase in high-temperature tensile strength, a 100% increase in creep rupture life and a 112% increase in fatigue life, a 92% increase in fatigue life and a 125% increase in fatigue life, a 36% decrease in crack propagation rate, a 77% increase in thermal fatigue life, a 63% decrease in oxidative weight gain, and a 7 percentage point increase in thermal stability.

[0181] These results fully demonstrate that the innovative process combination of this invention, including the dual-channel powder feeding system and cryogenic protective atmosphere in the arc-fed additive manufacturing process, timely forging and appropriate forging parameters in the synchronous micro-forging process, and subsequent hot isostatic pressing, homogenization, and solution + aging treatments, can effectively improve the microstructure and overall performance of high-temperature alloy turbine disks, especially their high-temperature performance. This is of great significance for improving the reliability, safety, and service life of aero-engine turbine disks, as well as reducing turbine disk weight and improving the thrust-to-weight ratio of engines.

[0182] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. Use of a double-channel powder feeding process in the preparation of a turbine disk blank for an aeroengine, characterized in that, The turbine disk blank is obtained by the following steps: S1. Arc powder feeding additive process: high-temperature alloy powder is deposited by gradient proportioning through a double-channel powder feeding system, and material gradient distribution is formed in the disc core, transition and disc rim areas, and a synchronous micro-forging process is used to apply dynamic mechanical deformation to the newly deposited layer in a high-temperature plastic state, and the obtained turbine disk blank is subjected to hot isostatic pressing treatment, high-temperature homogenization annealing in a vacuum furnace, and finally solid solution treatment and aging treatment to obtain the turbine disk blank; S2. Synchronous micro-forging process: mechanical deformation is applied to the material layer which is newly deposited and in a high-temperature plastic state at the same time of material accumulation, and dynamic extrusion or rolling is applied to the newly deposited layer by a micro-rolling forging mechanism, wherein the parameters of applying mechanical deformation are as follows: forging timing: immediately after each layer or a plurality of layers of material solidification and at a high temperature of 800-1150 DEG C; forging mode: one-way or multi-way dynamic extrusion or rolling is applied to the newly deposited layer by the micro-rolling forging mechanism; forging pressure: 50-200 MPa; forging mechanism moving speed: 1-5 m / min; reduction: 5%-20%; S3. Hot isostatic pressing heat treatment process: the turbine disk blank after additive manufacturing and synchronous micro-forging is subjected to hot isostatic pressing treatment; S4. Homogenization treatment: the blank after hot isostatic pressing treatment is subjected to high-temperature homogenization annealing in a vacuum furnace; S5. Solid solution + aging heat treatment process: the blank after homogenization treatment is subjected to solid solution treatment and aging treatment in a vacuum furnace to obtain the turbine disk blank, wherein the parameters of the solid solution treatment are as follows: temperature 800-1000 DEG C, holding time 2-4 hours, and cooling mode oil quenching, gas quenching or water quenching, and the parameters of the aging treatment are as follows: temperature 600-700 DEG C, holding time 8-16 hours, and cooling mode air cooling or furnace cooling. In S1, the gradient proportioning of the disc core area additive is that the powder feeding rate of channel one is set to 2.5-4.0 m / min, and the powder feeding rate of channel two is set to 0.5-1.5 m / min or 0 m / min; The gradient proportioning of the transition area additive is that as the additive path moves from the disc core to the disc rim, the powder feeding rate of channel one gradually decreases, and the powder feeding rate of channel two gradually increases; 2. Use according to claim 1, characterized in that, The gradient proportioning of the disc rim area additive is that the powder feeding rate of channel one is set to 0.5-1.5 m / min or 0 m / min, and the powder feeding rate of channel two is set to 2.5-4.0 m / min. In S1, the general parameters of the arc powder feeding additive process are as follows: Mixed powder channel powder feeding speed: 1-5 m / min; 3. Use according to claim 1, characterized in that, Arc current: 100-300 A; Arc voltage: 15-25 V; Deposited layer thickness: 0.5-2 mm; ​ ​ Interlayer residence time: 10-30s; Protective atmosphere: high-purity Ar gas, flow rate 10-25 L / min, temperature control at -15-0℃.

4. Use according to claim 1, characterized in that, In S3, the parameters of the hot isostatic pressing treatment are: Pressure: 100-150 MPa; Temperature: 1000-1200℃; Soaking time: 2-4 hours; Ramp-up / ramp-down rate: 3-10℃ / min.

5. The use according to claim 1, characterized in that, In S4, the parameters of the high-temperature homogenization annealing are: Treatment environment: vacuum degree better than 5×10⁻² Pa; Temperature: 900-1110℃; Soaking time: 1-3 hours; Cooling method: furnace cooling or controlled rate cooling.

6. Use according to claim 1, characterized in that, Specifically comprising the following steps: S1. Arc powder feeding additive process: depositing high-temperature alloy powder through a double-channel powder feeding system for gradient proportioning, specifically: Disc core area additive: set the powder feeding rate of channel one at 2.5-4.0 m / min, and set the powder feeding rate of channel two at 0.5-1.5 m / min or 0 m / min; Transition area additive: as the additive path moves from the disc core to the disc rim, gradually reduce the powder feeding rate of channel one and gradually increase the powder feeding rate of channel two; Disc rim area additive: set the powder feeding rate of channel one at 0.5-1.5 m / min or 0 m / min, and set the powder feeding rate of channel two at 2.5-4.0 m / min; The general parameters of the arc powder feeding additive process are: Mixed powder channel powder feeding speed: 1-5 m / min; Arc current: 100-300 A; Arc voltage: 15-25 V; Deposited layer thickness: 0.5-2 mm; Interlayer residence time: 10-30s; Protective atmosphere: high-purity Ar gas, flow rate 10-25 L / min, temperature control at -15-0℃. S2. Synchronous micro-forging process: simultaneously applying mechanical deformation to the newly deposited and high-temperature plastic state material layer during material accumulation, specifically: Forging timing: immediately after each layer or several layers of material solidification and at a high temperature of 800-1150℃; Forging method: applying unidirectional or multidirectional dynamic extrusion or rolling to the newly deposited layer through a micro-rolling forging mechanism; Forging pressure: 50-200 MPa; Forging mechanism moving speed: 1-5 m / min; Reduction rate: 5%-20%; S3. Hot isostatic pressing heat treatment process: hot isostatic pressing treatment of the turbine disc blank after additive manufacturing and synchronous micro-forging, with specific parameters as follows: Pressure: 100-150 MPa; Temperature: 1000-1200℃; Soaking time: 2-4 hours; Ramp-up / ramp-down rate: 3-10℃ / min. S4. Homogenization treatment: high-temperature homogenization annealing of the blank after hot isostatic pressing treatment in a vacuum furnace, with specific parameters as follows: Treatment environment: vacuum degree better than 5×10⁻² Pa; Temperature: 900-1110℃; Soaking time: 1-3 hours; Cooling method: furnace cooling or controlled rate cooling. S5. Solid solution + aging heat treatment process: standard solid solution treatment and aging treatment of the homogenized blank in a vacuum furnace with a vacuum degree ≤1×10⁻³ Pa to obtain a turbine disc blank, specifically: Solution treatment: temperature 800-1000℃, holding time 2-4 hours, cooling method oil quenching, gas quenching or water quenching; Aging treatment: temperature 600-700℃, holding time 8-16 hours, cooling method air cooling or furnace cooling.

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