Dual solid solution GH4169 alloy annular forge piece forging and heat treatment method

Abstract

The invention belongs to the field of high-temperature alloy hot working, and relates to a forging and heat treatment method for a dual solid solution GH4169 alloy annular forge piece. Comprising the steps of blanking, cake upsetting, punching, trestle chambering and on-machine chambering, and 80%-90% of deformation is completed at the on-machine chambering heating temperature of 990DEG C-1010DEG C; when the temperature of the forge piece is reduced to 930-940 DEG C after the forge piece is stopped for preset time, the remaining 10-20% deformation task is completed; the forged piece subjected to broaching is sequentially subjected to two times of solid solution and one time of aging, and the first time of solid solution comprises low-temperature section solid solution and high-temperature section solid solution; the secondary solid solution is high-temperature furnace entering, high-temperature solid solution is carried out, and the difference value between the temperature of the secondary solid solution and the temperature of a high-temperature section in the primary solid solution is 0-10 DEG C; and the aging temperature is as follows: entering the furnace when the furnace temperature is 500-600 DEG C, rapidly heating to 710-730 DEG C at the speed of 50-100 DEG C / h, preserving heat for 480-640 minutes, then cooling to 620 DEG C along with the furnace at the speed of 50 + / -10 DEG C / h, preserving heat for 480-640 minutes, taking out of the furnace after sufficient heat preservation, performing air cooling, selecting an air cooling mode, and ensuring that the total aging time is not less than 18 hours.

Description

Technical Field

[0001] This invention belongs to the field of high-temperature alloy hot working technology, specifically relating to a method for forging and heat treatment of GH4169 alloy ring forgings with double solid solution treatment. Background Technology

[0002] GH4169 alloy forgings are widely used in aero engines, with applications in many parts, including rotating parts and ring parts. This is mainly due to their excellent high-temperature performance and relatively mature development compared to other grades, meeting the requirements for both short and long service cycles.

[0003] The conventional manufacturing process for GH4169 alloy forgings typically involves only one solution heat treatment step during hot working. However, with increasing user demands for subsequent processing and use, some forgings require a second solution treatment. The first solution treatment is performed by the forging manufacturer after forging, while a second solution treatment is required upon arrival at the factory. This second treatment aims to achieve dimensional stability and further ensure precise dimensional control of the parts. Engineers are generally aware that repeated solution treatments generally lead to a decrease in mechanical properties, especially in yield strength during room temperature and high-temperature tensile testing, often failing to meet the mechanical property acceptance requirements of the parts standards. For aging processes, traditional methods typically involve a preheating step before 720℃, which cannot guarantee the sufficient precipitation of the main strengthening phase (γ-phase), negatively impacting mechanical properties. Based on research into the two-stage solution treatment process, and through extensive experimentation by engineers, specific requirements for aging have been established, resulting in further improvements in the mechanical properties of the forgings.

[0004] To address the issue of mechanical property degradation in GH4169 alloy forgings due to repeated solid solution treatment, technicians conducted extensive technical practice and experimental exploration, mastering a forging and heat treatment method for GH4169 alloy ring forgings with double solid solution treatment. This method can effectively improve the performance degradation problem and meet the usage requirements of the parts. Summary of the Invention

[0005] Objective of the invention: To provide a method for forging and heat treatment of GH4169 alloy ring forgings with double solid solution treatment.

[0006] Technical solution: A method for forging and heat treatment of a double-solution GH4169 alloy ring forging includes: Step 1: Cut the material and chamfer both ends of the bar evenly; Step 2: Upsetting and punching the bar stock; Step 3: After punching the hole in the upsetting blank, the forging is enlarged using a frame. Step 4: After the forging frame is enlarged on the machine, the hole is enlarged again. The forging is heated to 990℃~1010℃ to complete 80%~90% of the deformation. The forging is stopped for a predetermined time and the temperature of the forging drops to 930℃~940℃ before the remaining 10%~20% of the deformation is completed. The forging is then cooled. Step 5: Perform two solution treatments and one aging process on the forgings after hole expansion in Step 4. The first solution treatment includes a low-temperature solution treatment and a high-temperature solution treatment. The second solution treatment involves high-temperature furnace entry and high-temperature solution treatment. The temperature difference between the second solution treatment and the high-temperature section of the first solution treatment is 0-10 degrees Celsius. Aging temperature: Enter the furnace at a furnace temperature of 500℃ to 600℃, rapidly heat to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h, hold for 480min to 640min, then cool in the furnace at a rate of 50±10℃ / h to 620℃ for a second holding, and hold for 480min to 640min. After sufficient holding, remove from the furnace and air cool. Air cooling is selected as the cooling method to ensure that the total aging time is not less than 18h.

[0007] Furthermore, it also includes: Step 6: Perform a second aging on the forging after the first aging.

[0008] Further, step 2 specifically involves: upsetting and punching the bar stock, with a deformation of 40% to 60%, a heating temperature of 1010℃ to 1030℃, and air cooling.

[0009] Further, step 3 specifically involves: After punching holes in the upsetting disc on a 3t free forging hammer, the forging is enlarged using a frame, with a deformation of 20%~50%, a heating temperature of 1000℃~1020℃, and an air cooling method.

[0010] Further, step 4 specifically involves: after the forging is enlarged on a reamer, the forging is enlarged to a deformation rate of 10% to 40%, and the heating temperature is 990℃ to 1010℃. During the forging process, the forging temperature is monitored. After completing 80% to 90% of the deformation task according to the heating temperature, the forging is held for a predetermined time. The length of the holding time depends on the forging temperature. When the forging temperature reaches 930℃ to 940℃, the remaining 10% to 20% of the deformation task is completed.

[0011] Furthermore, in step 4, the cooling method is as follows: rapid air cooling for 1-3 minutes after forging, cooling to below 720℃, and then switching to air cooling.

[0012] Furthermore, in step 5, the first solution treatment is specifically as follows: the forging is put into the furnace at a furnace temperature of 400℃ to 500℃, and the temperature is increased to 650℃ to 720℃ at a rate of 50℃ to 100℃ / h, held for 60min to 120min, and then increased to 950℃ to 970℃ at a rate of 50℃ to 100℃ / h, held for 60min to 120min. The cooling method is oil cooling, the oil cooling temperature does not exceed 50℃, and the number of forgings loaded into the furnace does not exceed 2 / 3 of the furnace volume.

[0013] Furthermore, in step 5, the secondary solution treatment is specifically as follows: the furnace is introduced when the furnace temperature is 700℃ to 800℃, and the temperature is rapidly increased to 950℃ to 960℃ at a rate of 50℃ to 100℃ / h, and held for 60min to 120min. The cooling method is oil cooling, the oil cooling temperature does not exceed 50℃, and the number of items loaded into the furnace does not exceed 2 / 3 of the furnace volume.

[0014] Furthermore, the second time limit is specifically defined as follows: When the furnace temperature is 500℃ to 600℃, the furnace is fed in and rapidly heated to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h. The temperature is held for 480min to 640min. Then, the furnace is cooled to 620℃ at a rate of 50±10℃ / h for a second holding period of 480min to 640min. After sufficient holding, the furnace is removed and air-cooled. Air cooling is selected as the cooling method to ensure that the total aging time is not less than 18h. The number of furnace-loaded items should not exceed 2 / 3 of the furnace volume.

[0015] Furthermore, steps 2 and 3 are performed using a 3t free forging hammer.

[0016] Beneficial effects: This invention addresses the issue of repeatedly solution-treated GH4169 alloy forgings failing to meet standards regarding room temperature and high temperature tensile yield strength decay by optimizing the forging and heat treatment processes. Various fluctuations in the heat treatment requirements specified in the standards were repeatedly studied during implementation, and conditions favorable to mechanical properties were optimized through experiments and practical exploration. Ultimately, a forging and heat treatment manufacturing process for double-solution-treated GH4169 alloy forgings was mastered, guiding the development of forging and heat treatment processes for repeatedly solution-treated forgings in the field, maximizing material properties and meeting design requirements. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] The features and illustrative embodiments of various aspects of the present invention will now be described in detail. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without requiring some of these specific details. The following description of embodiments is merely intended to provide a better understanding of the invention by illustrating examples of the invention. The invention is by no means limited to any specific setup and method set forth below, but covers any improvements, substitutions, and modifications to the structures, methods, and devices without departing from the spirit of the invention.

[0019] In the description of this invention, the use of ordinal numbers (e.g., "first and second", etc.) is for distinguishing objects and is not limited to the order, and should not be construed as indicating or implying relative importance.

[0020] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly, encompassing both direct connection and indirect connection via an intermediate medium. Those skilled in the art can understand the specific meaning of these terms in this invention based on the specific circumstances.

[0021] It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other, and the various embodiments can be referenced and cited from each other.

[0022] This invention addresses the issue of insufficient yield strength at room temperature and high temperature during repeated solution treatment forgings by optimizing the forging and heat treatment processes of GH4169 alloy. During forging, variable measures are employed to optimize deformation and cooling methods. The deformation amount is redistributed to ensure sufficient precipitation and growth of the γ” phase. Cooling is performed first with air cooling followed by general air cooling, rapidly precipitating the γ” phase and improving mechanical properties. The heat treatment process design intentionally establishes a correlation between the previously unrelated two solution treatment processes. The temperature difference between the two solutions should not be too large, typically controlled within 0–10℃. Furthermore, a preheating step should be set at the low-temperature stage of the first solution treatment heating process, with a selectable step temperature between 650℃ and 720℃. This preheating step prepares the energy storage for subsequent high-temperature solution treatment heating, improving microstructural stability. The high-temperature stage temperature is selected between 950℃ and 980℃. Cooling can be achieved through rapid cooling methods such as air cooling, diffused air cooling, oil cooling, or water cooling, which can be adjusted appropriately based on the stress and deformation during subsequent part processing, with the principle being to cool as quickly as possible. For secondary solution treatment, the temperature should be rapidly increased to the required level without the need for a preheating step. After the combined secondary solution treatment, the forging undergoes two aging processes. For the first aging, the temperature should be rapidly increased to the aging temperature without the need for a preheating step. After a sufficient holding time, the forging should be furnace cooled at a rate of 50±10℃ / h to 620℃ for the second aging holding. After a sufficient holding time, the forging should be removed from the furnace and air-cooled.

[0023] The following section uses a GH4169 alloy ring forging of a certain type of machine as an example to introduce the forging and heat treatment process of the forging, and provides a detailed explanation of the process steps of the present invention.

[0024] A method for forging and heat treatment of a double-solution GH4169 alloy ring forging includes the following steps: Step 1: Cut the material and chamfer both ends of the bar evenly; Step 2: Upset and punch the bar stock on a 3t free forging hammer, with a deformation of 40%~60%, a punch size of Φ90~Φ110, a heating temperature of 1010℃~1030℃, and an air cooling method. Step 3: After punching the hole in the upsetting on a 3t free forging hammer, the forging is enlarged by a frame, with a deformation of 20%~50%, a heating temperature of 1000℃~1020℃, and an air cooling method. Step 4: After the forging frame has been expanded on a Φ1200mm reamer, expand the hole again, with a deformation of 10%~40%. The heating temperature is 990℃~1010℃. Monitor the forging temperature during forging. First, complete 80%~90% of the deformation at the heating temperature, then pause for 5~15 seconds. The pause time depends on the forging temperature. When the forging temperature reaches 930℃~940℃, complete the remaining 10%~20% of the deformation. After forging, quickly air cool for 1~3 minutes until the temperature drops below 720℃, then switch to air cooling.

[0025] The γ” phase of GH4169 alloy begins to precipitate at 930℃. Therefore, by increasing the time when the temperature is about 10℃ closer to 930℃, the γ” phase can be fully precipitated. The cooling method of first air cooling and then air cooling can suppress the precipitation of δ phase and obtain fine and uniform γ” phase, thereby improving the strength of the forging.

[0026] Step 5: Cut the prepared GH4169 alloy ring forging into 3 parts at 120°C, mark them as SYA, SYB and SYC, and conduct heat treatment tests under different conditions.

[0027] Step 6: SYA forging heat treatment temperature settings. First solution treatment temperature: When the furnace temperature is 400℃ to 500℃, the test forging is put into the furnace. The temperature is increased at a rate of 50℃~100℃ / h to the low temperature stage. The low temperature stage temperature is between 650℃ and 720℃, the heating rate is between 50℃ and 100℃ / h, and the holding time is between 60min and 120min. The high temperature stage temperature is between 970℃ and 980℃, the heating rate is between 50℃ and 100℃ / h, and the holding time is between 60min and 120min. The cooling method is oil cooling, the oil cooling temperature does not exceed 50℃, and the number of forgings loaded into the furnace does not exceed 2 / 3 of the furnace volume. Secondary solution treatment temperature: When the furnace temperature is 700℃ to 800℃, the furnace is rapidly heated to 950℃ to 960℃ at a rate of 50℃ to 100℃ / h, and held for 60min to 120min. Oil cooling is used, with the oil cooling temperature not exceeding 50℃. The number of furnace loads should not exceed 2 / 3 of the furnace volume. Aging temperature: When the furnace temperature is 500℃ to 600℃, the furnace is rapidly heated to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h, and held for 480min to 640min. Then, the furnace is cooled to 620℃ at a rate of 50±10℃ / h for secondary aging, and held for 480min to 640min. After sufficient holding, the furnace is removed and air-cooled, ensuring a total aging time of no less than 18 hours.

[0028] Step 7: SYB forging heat treatment temperature settings. First solution treatment temperature: When the furnace temperature is 400℃ to 500℃, the test forging is put into the furnace and heated at a rate of 50℃~100℃ / h to the low temperature stage. The low temperature stage temperature is between 650℃ and 720℃, the heating rate is between 50℃ and 100℃ / h, and the holding time is between 60min and 120min. The high temperature stage temperature is between 950℃ and 970℃, the heating rate is between 50℃ and 100℃ / h, and the holding time is between 60min and 120min. The cooling method is oil cooling, the oil cooling temperature does not exceed 50℃, and the number of forgings loaded into the furnace does not exceed 2 / 3 of the furnace volume. Secondary solution treatment temperature: When the furnace temperature is 700℃ to 800℃, the furnace is rapidly heated to 950℃ to 960℃ at a rate of 50℃ to 100℃ / h, and held for 60min to 120min. Oil cooling is used, with the oil cooling temperature not exceeding 50℃. The number of items loaded into the furnace should not exceed 2 / 3 of the furnace volume. Aging temperature: When the furnace temperature is 500℃ to 600℃, the furnace is rapidly heated to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h, and held for 480min to 640min. Then, the furnace is cooled to 620℃ at a rate of 50±10℃ / h for a secondary holding period of 480min to 640min. After sufficient holding, the furnace is removed and air-cooled, ensuring a total aging time of at least 18 hours.

[0029] Step 8: SYC forging heat treatment temperature settings. First solution treatment temperature: When the furnace temperature is 400℃ to 500℃, the test forging is put into the furnace. The temperature is increased at a rate of 50℃~100℃ / h to the low temperature stage. The low temperature stage temperature is between 650℃ and 720℃, the heating rate is between 50℃ and 100℃ / h, and the holding time is between 60min and 120min. The high temperature stage temperature is between 970℃ and 980℃, the heating rate is between 50℃ and 100℃ / h, and the holding time is between 60min and 120min. The cooling method is oil cooling, the oil cooling temperature does not exceed 50℃, and the number of forgings loaded into the furnace does not exceed 2 / 3 of the furnace volume. Secondary solution treatment temperature: When the furnace temperature is 700℃ to 800℃, the furnace is rapidly heated to 970℃ to 980℃ at a rate of 50℃ to 100℃ / h, and held for 60min to 120min. Oil cooling is used, with the oil cooling temperature not exceeding 50℃. The number of furnace-loaded items should not exceed 2 / 3 of the furnace volume. Aging temperature: When the furnace temperature is 500℃ to 600℃, the furnace is rapidly heated to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h, and held for 480min to 640min. Then, the furnace is cooled to 620℃ at a rate of 50±10℃ / h for secondary aging and holding for 480min to 640min. After sufficient holding, the furnace is removed and air-cooled. Air cooling is used to ensure a total aging time of not less than 18 hours. The number of furnace-loaded items should not exceed 2 / 3 of the furnace volume.

[0030] Step 9: After heat treatment, test the room temperature deep drawing and 650℃ high temperature tensile properties of SYA, SYB and SYC test pieces.

[0031] Step 10: Supplement the aging test for SYA, SYB, and SYC test pieces. Place them in the furnace when the furnace temperature is 500℃ to 600℃, and rapidly heat them to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h. Hold them at this temperature for 480min to 640min. Then, cool them in the furnace at a rate of 50±10℃ / h to 620℃ for a second holding period of 480min to 640min. After sufficient holding, remove them from the furnace and air cool them. Choose air cooling as the cooling method to ensure that the total aging time is not less than 18h. The number of pieces loaded into the furnace should not exceed 2 / 3 of the furnace volume.

[0032] Step 11: After the supplementary aging is completed, test the room temperature deep drawing and 650℃ high temperature tensile properties of SYA, SYB and SYC test pieces.

[0033] Step 12: Compare the degree of performance degradation between two room temperature tensile tests and a high temperature tensile test.

[0034] Example 1 The GH4169 alloy ring forging described in this invention has an outer diameter of Φ568mm, an inner diameter of Φ512mm, and a height of 68mm. Different primary solution heat treatment regimes and secondary solution heat treatment regimes are designed to test the degree of mechanical property degradation and establish the correlation between the two solution temperatures.

[0035] The manufacturing process is detailed below: 1. Cutting: Sawing machine, cutting size φ200×140mm; 2. Billet machining: Chamfering of both ends of the bar stock with a radius of R10; 3. Upsetting and punching: Upsetting φ200×140 along the axial direction to φ280×70, with a center punch size of φ110, completed in two heat treatments, with a deformation of 50%, a heating temperature of 1020℃, and an air cooling method; 4. Expanding the hole in the frame: First expand the hole from ~φ280×φ110×70 to ~φ330×φ200×70, with a deformation of 24%, then expand the hole to ~φ400×φ300×70, with a deformation of 23%. The process is completed in two stages. The heating temperature is 1010℃, and the cooling method is air cooling. 5. Hole Reaming: First, ream the hole from ~φ400×φ300×70 to ~φ435×φ350×70, with a deformation of 15%. Then, ream the hole to ~φ566×φ503×70, with a deformation of 25%, hold for 10 seconds, and when the forging temperature is 940℃, begin reaming to ~φ570×φ510×70, with a deformation of 5%. Complete the process in two stages, with a heating temperature of 1000℃. During cooling, rapidly air-cool for 2 minutes until the temperature drops below 720℃, then switch to air cooling. 6. After forging, the forging is cut into 3 parts at 120°C with a notch width ≤5mm. The parts are marked as SYA, SYB, and SYC respectively, and then subjected to heat treatment tests. 7. SYA test specimens undergo heat treatment using a single solution treatment, double solution treatment, and aging process. Single solution treatment temperature: <500℃, furnace entry, heating at 100℃ / h to 700℃, holding for 60 min, then heating at 50℃ / h to 975℃, holding for 60 min, followed by oil cooling (oil cooling temperature not exceeding 50℃). Double solution treatment temperature: <800℃, furnace entry, heating at 100℃ / h to 955℃, holding for 60 min, followed by oil cooling (oil cooling temperature not exceeding 50℃). Aging temperature: <600℃, furnace entry, rapid heating at 100℃ / h to 720℃, holding for 480 min, then furnace cooling at 50±10℃ / h to 620℃ for double aging (holding for 480 min), followed by sufficient holding and air cooling for 18 hours. 8. SYB test pieces undergo heat treatment with a first solution treatment, second solution treatment, and aging process. First solution treatment temperature: <500℃, furnace entry, heating at 100℃ / h to 700℃, holding for 60 min, then heating at 50℃ / h to 960℃, holding for 60 min, followed by oil cooling (oil cooling temperature not exceeding 50℃). Second solution treatment temperature: <800℃, furnace entry, heating at 100℃ / h to 955℃, holding for 60 min, followed by oil cooling (oil cooling temperature not exceeding 50℃). Aging temperature: <600℃, furnace entry, rapid heating at 100℃ / h to 720℃, holding for 480 min, then furnace cooling at 50±10℃ / h to 620℃ for a second aging holding of 480 min, followed by sufficient holding and air cooling for 18 hours. 9. SYC test pieces undergo heat treatment. The heat treatment regime is one solution treatment, two solution treatments, and aging. First solution treatment temperature: <500℃, enter the furnace, heat to 700℃ at a rate of 100℃ / h, hold for 60 min, then heat to 975℃ at a rate of 50℃ / h, hold for 60 min, followed by oil cooling, with the oil cooling temperature not exceeding 50℃. Second solution treatment temperature: <800℃, enter the furnace, heat to 975℃ at a rate of 100℃ / h, hold for 60 min, followed by oil cooling, with the oil cooling temperature not exceeding 50℃. Aging temperature: <600℃, enter the furnace, rapidly heat to 720℃ at a rate of 100℃ / h, hold for 480 min, then furnace cool to 620℃ at a rate of 50±10℃ / h for a second aging holding of 480 min, after sufficient holding, remove from the furnace and air cool for 18 hours. 10. Test the room temperature deep drawing and 650℃ high temperature tensile properties of SYA, SYB, and SYC specimens; 11. Supplement the aging test for SYA, SYB, and SYC test pieces. Aging temperature: <600℃. Put the piece into the furnace and rapidly heat it to 720℃ at a rate of 100℃ / h. Hold it for 480 min. Then, cool it in the furnace at a rate of 50±10℃ / h to 620℃ for a second aging and holding period of 480 min. After sufficient holding, remove the piece from the furnace and air cool it for 18 h. 12. After the supplementary aging is completed, test the room temperature deep drawing and 650℃ high temperature tensile properties of the SYA, SYB, and SYC test pieces; The three test pieces after the heat treatment experiment were tested: room temperature yield strength of the three forgings after one solution treatment, two solution treatments, and aging: SYA: σ 0.2 =1091MPa, SYB: σ 0.2 =1172MPa, SYC: σ 0.2 =1126MPa 650℃ High Temperature Yield Strength: SYA: σ 0.2 =905MPa, SYB: σ 0.2 =969MPa, SYC: σ 0.2 =922MPa.

[0036] Supplement the room temperature yield strength of the three forgings after aging: SYA: σ 0.2 =1121MPa, SYB: σ 0.2 =1154MPa, SYC: σ 0.2 =1191MPa, yield strength at 650℃: SYA: σ 0.2 =930MPa, SYB: σ 0.2 =1031MPa, SYC: σ 0.2 =984MPa.

[0037] The primary solution treatment temperature is between 950℃ and 970℃, and the secondary solution treatment temperature is between 950℃ and 960℃. When the two solution treatment temperatures are close, the yield strength decreases relatively little. This heat treatment process can produce forgings that meet standard requirements, with low processing stress, and can guarantee the dimensional accuracy of the parts.

[0038] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for forging and heat treatment of a double-solution GH4169 alloy ring forging, characterized in that, include: Step 1: Cut the material and chamfer both ends of the bar evenly; Step 2: Upsetting and punching the bar stock; Step 3: After punching the hole in the upsetting blank, the forging is enlarged using a frame. Step 4: After the forging frame is enlarged on the machine, the hole is enlarged again. The forging is heated to 990℃~1010℃ to complete 80%~90% of the deformation. The forging is stopped for a predetermined time and the temperature of the forging drops to 930℃~940℃ before the remaining 10%~20% of the deformation is completed. The forging is then cooled. Step 5: Perform two solution treatments and one aging process on the forgings after hole expansion in Step 4. The first solution treatment includes a low-temperature solution treatment and a high-temperature solution treatment. The second solution treatment involves high-temperature furnace entry and high-temperature solution treatment. The temperature difference between the second solution treatment and the high-temperature section of the first solution treatment is 0-10 degrees Celsius. Aging temperature: Enter the furnace at a furnace temperature of 500℃ to 600℃, rapidly heat to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h, hold for 480min to 640min, then cool in the furnace at a rate of 50±10℃ / h to 620℃ for a second holding, and hold for 480min to 640min. After sufficient holding, remove from the furnace and air cool. Air cooling is selected as the cooling method to ensure that the total aging time is not less than 18h.

2. The method according to claim 1, characterized in that, Also includes: Step 6: Perform a second aging on the forging after the first aging.

3. The method according to claim 2, characterized in that, Step 2, specifically: upsetting and punching the bar stock, with a deformation of 40%~60%, heating temperature of 1010℃~1030℃, and air cooling.

4. The method according to claim 3, characterized in that, Step 3, specifically: After punching holes in the upsetting disc on a 3t free forging hammer, the forging is enlarged using a frame, with a deformation of 20%~50%, a heating temperature of 1000℃~1020℃, and an air cooling method.

5. The method according to claim 4, characterized in that, Step 4, specifically: After the forging is enlarged on the reamer, the deformation is increased by 10% to 40% and the heating temperature is 990℃ to 1010℃. During the forging process, the forging temperature is monitored. After completing 80% to 90% of the deformation task according to the heating temperature, the workpiece is held for a predetermined time. The length of the holding time depends on the forging temperature. When the forging temperature reaches 930℃ to 940℃, the remaining 10% to 20% of the deformation task is completed.

6. The method according to claim 5, characterized in that, In step 4, the cooling method is as follows: rapid air cooling for 1-3 minutes after forging, cooling to below 720℃, and then switching to air cooling.

7. The method according to claim 6, characterized in that, In step 5, the solution treatment is performed as follows: the forging is placed into the furnace at a furnace temperature of 400℃ to 500℃, and the temperature is increased to 650℃ to 720℃ at a rate of 50℃ to 100℃ / h, held for 60min to 120min, and then increased to 950℃ to 970℃ at a rate of 50℃ to 100℃ / h, held for 60min to 120min. The cooling method is oil cooling, the oil cooling temperature does not exceed 50℃, and the number of forgings loaded into the furnace does not exceed 2 / 3 of the furnace volume.

8. The method according to claim 7, characterized in that, In step 5, the secondary solution treatment is carried out as follows: the furnace is put into the furnace when the furnace temperature is 700℃ to 800℃, and the temperature is rapidly increased to 950℃ to 960℃ at a rate of 50℃ to 100℃ / h. The temperature is held for 60min to 120min. The cooling method is oil cooling, and the oil cooling temperature does not exceed 50℃. The number of items loaded into the furnace does not exceed 2 / 3 of the furnace volume.

9. The method according to claim 8, characterized in that, The second time limit is specifically as follows: When the furnace temperature is 500℃ to 600℃, the furnace is fed in and rapidly heated to 710℃ to 730℃ at a rate of 50℃ to 100℃ / h. The temperature is held for 480min to 640min. Then, the furnace is cooled to 620℃ at a rate of 50±10℃ / h for a second holding period of 480min to 640min. After sufficient holding, the furnace is removed and air-cooled. Air cooling is selected as the cooling method to ensure that the total aging time is not less than 18h. The number of furnace-loaded items should not exceed 2 / 3 of the furnace volume.

10. The method according to claim 1, characterized in that, Steps 2 and 3 are performed using a 3t free forging hammer.