Heat treatment method for improving mechanical properties of additive manufactured gh4169 superalloy parts

Abstract

The application discloses a heat treatment method for improving mechanical properties of an additive manufacturing GH4169 high-temperature alloy part, and belongs to the technical field of heat treatment, which comprises the following steps: S1, placing the additive manufacturing GH4169 high-temperature alloy part into a hot isostatic pressing device for heat preservation and pressure preservation treatment; S2, placing the additive manufacturing GH4169 high-temperature alloy part obtained in the step S1 into a vacuum heat treatment furnace for aging treatment; S3, placing the additive manufacturing GH4169 high-temperature alloy part obtained in the step S2 into a deep cooling control box for deep cooling treatment; S4, placing the additive manufacturing GH4169 high-temperature alloy part obtained in the step S3 after the cooling treatment into the vacuum heat treatment furnace for heating treatment; S5, placing the additive manufacturing GH4169 high-temperature alloy part obtained in the step S4 after the aging treatment into the deep cooling control box for deep cooling treatment; and S6, placing the additive manufacturing GH4169 high-temperature alloy part obtained in the step S5 after the cooling treatment into the vacuum heat treatment furnace for heating treatment. The application has the advantages of reducing heat treatment procedures and reducing working hours.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heat treatment, in particular to a heat treatment method for improving mechanical properties of an additive manufacturing GH4169 high-temperature alloy part. BACKGROUND

[0002] GH4169 high-temperature alloy is a precipitation-strengthened nickel-based high-temperature alloy, which has good high-temperature mechanical properties, oxidation resistance and corrosion resistance, and is one of important materials for manufacturing aero-engine parts. With the rapid development of aero-engines, aero-engine parts are also developing in the direction of complexity and structural integration. The existing traditional manufacturing technology cannot meet the manufacturing requirements of complex structure parts, which greatly limits the improvement of aero-engine performance. Additive manufacturing technology is a near-net-shape process, which is more suitable for the manufacturing of complex structure parts compared with traditional manufacturing processes, and thus has been more and more widely used in the field of aero-engine manufacturing.

[0003] The cooling speed of the additive manufacturing process is fast, so the as-deposited mechanical properties of the GH4169 high-temperature alloy cannot usually meet the use requirements and must be used after heat treatment. At present, the additive manufacturing GH4169 high-temperature alloy usually adopts the same heat treatment process as the traditional manufacturing process.

[0004] There are usually pores in the additive manufacturing metal material, which may adversely affect the mechanical properties of the formed material. At present, the mechanical properties of the material are usually improved by heat isostatic pressing, solid solution treatment and aging treatment processes, but the conventional process has more process procedures and longer working hours. SUMMARY

[0005] The present application provides a heat treatment method for improving the mechanical properties of an additive manufacturing GH4169 high-temperature alloy part to solve the technical problems of the existing process having more process procedures and longer working hours.

[0006] According to one aspect of the present application, a heat treatment method for improving the mechanical properties of an additive manufacturing GH4169 high-temperature alloy part is provided, comprising the following steps: S1, placing the additive manufacturing GH4169 high-temperature alloy part into a heat isostatic pressing device for heat preservation and pressure preservation treatment;

[0007] S2, placing the additive manufacturing GH4169 high-temperature alloy part subjected to heat isostatic pressing and solid solution treatment obtained in step S1 into a vacuum heat treatment furnace for aging treatment;

[0008] S3, placing the additive manufacturing GH4169 high-temperature alloy part subjected to aging treatment obtained in step S2 into a deep cooling control box for deep cooling treatment;

[0009] S4, the cooled additive manufacturing GH4169 high-temperature alloy part obtained in step S3 is placed into a vacuum heat treatment furnace for heating treatment;

[0010] S5, the aged additive manufacturing GH4169 high-temperature alloy part obtained in step S4 is placed into a deep cooling control box for deep cooling treatment;

[0011] S6, the cooled additive manufacturing GH4169 high-temperature alloy part obtained in step S5 is placed into a vacuum heat treatment furnace for heating treatment.

[0012] Optionally, in step S1, the temperature of the heat preservation and pressure maintaining treatment in the hot isostatic pressing equipment is 1100-1250℃, the pressure is 130-150 MPa, and the time is 1h±15min.

[0013] Optionally, in step S1, after the heat preservation and pressure maintaining treatment is completed, the pressure is first reduced to below 100 MPa, argon is then filled to reduce the temperature, and when the pressure in the furnace is reduced to below 31 MPa, the filling of argon is stopped.

[0014] Optionally, in step S1, when the furnace is cooled to below 300℃, the pressure is started to be released until the pressure in the furnace is 0.

[0015] Optionally, in step S2, after the temperature of the vacuum heat treatment furnace is raised to 700-750℃, the temperature is maintained for 6-9h; after the temperature maintaining at 700-750℃ is completed, the temperature is cooled to 600-650℃ at a cooling rate of 30-50℃ / h, and the temperature is maintained for 6-9h.

[0016] Optionally, in step S2, after the temperature maintaining at 600-650℃ is completed, argon is filled to cool the temperature to room temperature.

[0017] Optionally, in the deep cooling treatment of step 3, the cooling rate is 5-10℃ / min, and the temperature is maintained for 24-48h after being cooled to -130--180℃.

[0018] Optionally, in the heating treatment of step 4, the temperature is raised to 700-750℃, and the temperature is maintained for 6-9h; after the temperature maintaining at 700-750℃ is completed, the temperature is cooled to 600-650℃ at a cooling rate of 30-50℃ / h, and the temperature is maintained for 6-9h; after the temperature maintaining at 600-650℃ is completed, argon is filled to cool the temperature to room temperature.

[0019] Optionally, in the deep cooling treatment of step 5, the cooling rate is 5-10℃ / min, and the temperature is maintained for 24-48h after being cooled to -130--180℃.

[0020] Optionally, in the heating treatment of step 6, after being heated to 700-750 DEG C, the temperature is kept for 6-9 hours; after the temperature keeping at 700-750 DEG C, the temperature is cooled to 600-650 DEG C at a cooling rate of 30-50 DEG C / h, and the temperature is kept for 6-9 hours; after the temperature keeping at 600-650 DEG C, argon is filled to cool to room temperature.

[0021] In summary, the present application includes at least one of the following beneficial technical effects:

[0022] The present application is directed to the heat isostatic pressing treatment and solid solution treatment of the additive manufacturing GH4169 high-temperature alloy. Through high-temperature solid solution treatment, the harmful phase formed in the rapid cooling process of the additive manufacturing can be fully dissolved. Through heat isostatic pressing, the pores, micro-cracks and other defects in the material can be eliminated. The solid solution treatment can be completed synchronously when the heat isostatic pressing treatment is performed, so that the process steps can be simplified and the process time can be shortened. For the GH4169 high-temperature alloy, the traditional heat treatment system only includes solid solution and aging treatment. For the additive manufacturing GH4169 high-temperature alloy, due to the fast cooling speed in the additive manufacturing process, the size of the grains of the forming material is small, and the mechanical properties are good. However, after the heat treatment, the grain size may grow, resulting in the decrease of the mechanical properties. Therefore, the additive manufacturing GH4169 high-temperature alloy which has been subjected to the heat isostatic pressing and heat treatment is subjected to two cycles of deep cooling treatment, so that the grains can be refined, the grains can be rotated, a large number of twin crystals can be formed, the lattice constant of the matrix can be reduced, and the second phase particles can be precipitated. Through the above heat treatment which is directed to the organization and performance characteristics of the additive manufacturing GH4169 high-temperature alloy, the mechanical properties can be improved, and the engineering application of the additive manufacturing GH4169 high-temperature alloy parts can be promoted.

[0023] In addition to the objects, features, and advantages described above, the present application has other objects, features, and advantages. The present application is further described below in detail. DETAILED DESCRIPTION

[0024] The embodiments of the present application are described in detail below, but the present application can be implemented in various different ways as defined and covered by the following.

[0025] The present application is further described in detail below.

[0026] The embodiments of the present application disclose a heat treatment method for improving the mechanical properties of an additive manufacturing GH4169 high-temperature alloy part, comprising:

[0027] S1, the additive manufacturing GH4169 high-temperature alloy part is put into a heat isostatic pressing device for temperature keeping and pressure keeping treatment;

[0028] S2, the additive manufacturing GH4169 high-temperature alloy part subjected to the heat isostatic pressing treatment and the solid solution treatment obtained in step S1 is put into a vacuum heat treatment furnace for aging treatment;

[0029] S3, the age-treated additive manufacturing GH4169 high-temperature alloy part obtained in step S2 is placed in a deep cooling control box for deep cooling treatment;

[0030] S4, the cooled additive manufacturing GH4169 high-temperature alloy part obtained in step S3 is placed in a vacuum heat treatment furnace for heating treatment;

[0031] S5, the age-treated additive manufacturing GH4169 high-temperature alloy part obtained in step S4 is placed in a deep cooling control box for deep cooling treatment;

[0032] S6, the cooled additive manufacturing GH4169 high-temperature alloy part obtained in step S5 is placed in a vacuum heat treatment furnace for heating treatment.

[0033] Specifically, in step S1, the temperature of the heat preservation and pressure maintaining treatment in the hot isostatic pressing equipment is 1100-1250℃, the pressure is 130MPa-150MPa, and the time is 1h±15min. In step S1, after the heat preservation and pressure maintaining is completed, the pressure is first reduced to below 100MPa, then argon is filled to cool down, and when the pressure in the furnace is reduced to below 31MPa, the filling of argon is stopped. In step S1, when the furnace is cooled to below 300℃, the pressure is released until the pressure in the furnace is 0.

[0034] The purpose of step S1 is to significantly improve the defects such as pores and micro-cracks formed during the additive manufacturing process by combining hot isostatic pressing and high-temperature solid solution treatment, and to improve the density and uniformity of the material. In the high-temperature solid solution process, harmful phases and non-uniform phases are dissolved in the matrix, which restores the microstructure of the material to be uniform and provides a more ideal basis for subsequent aging treatment. At the same time, the hot isostatic pressing process can also rearrange the grains in the material, reduce the residual stress in the material, optimize the grain structure, and significantly improve the plasticity and toughness of the material. In addition, by simultaneously performing hot isostatic pressing and solid solution treatment in a high-temperature and high-pressure environment, the process steps are simplified, the entire processing flow is shortened, the production efficiency is improved, and the time and energy costs are saved. Therefore, the key of step 1 is to eliminate the micro-defects in the additive manufacturing process by simultaneously performing hot isostatic pressing and solid solution treatment, optimize the microstructure, and improve the mechanical properties of the material, which lays a solid foundation for subsequent aging and deep cooling treatment, and enables the GH4169 high-temperature alloy to have excellent comprehensive performance under high temperature and high stress conditions.

[0035] In step S2, the temperature of the vacuum heat treatment furnace is raised to 700-750°C, and then held for 6-9 hours. After holding at 700-750°C, the temperature is cooled to 600-650°C at a rate of 30-50°C / h, and then held for 6-9 hours. After holding at 600-650°C, the vacuum heat treatment furnace is filled with argon and cooled to room temperature.

[0036] The purpose of step 2 is to further improve the microstructure and mechanical properties of the additive manufacturing GH4169 high-temperature alloy parts by aging treatment after hot isostatic pressing and solid solution treatment in step 1. In this step, the parts are placed in a vacuum heat treatment furnace for aging treatment, usually heated to 700-750°C, so that the alloy elements inside the material can be redistributed, and the precipitation of γ' and γ'' phases is promoted. The formation of these precipitates can significantly improve the strength, hardness and creep resistance of the alloy, thereby enhancing the durability and stability of the material in high-temperature environments. At the same time, aging treatment can also improve the crystal lattice structure of the material, making it more stable, and can reduce the residual stress inside the parts due to solid solution treatment, improving the toughness and ductility of the material. In addition, through reasonable aging treatment, the morphology and size of the precipitates can be controlled, thereby optimizing the microstructure of the material, so that the GH4169 alloy can exhibit excellent comprehensive performance under high-temperature and high-pressure working conditions. Therefore, the aging treatment in step 2 not only further complements the previous hot isostatic pressing and solid solution treatment, but also controls the structure and strengthening phase precipitation inside the material through micro-adjustment, so that the mechanical properties of the alloy reach the best state, providing a more optimized material basis for subsequent deep cryogenic treatment and heating treatment

[0037] In step 3, the cooling rate is 5-10℃ / min, and the temperature is cooled to -130 to -180℃ and kept for 24-48h. The purpose of step 3 is to further optimize the microstructure and mechanical properties of the additive manufacturing GH4169 high-temperature alloy parts by deep cryogenic treatment after aging treatment in step 2. In this step, the parts are placed in a deep cryogenic control box, and the temperature is rapidly reduced to -130 to -180℃ at a cooling rate of 5-10℃ / min, and kept at this temperature for 24-48h. Through such deep cryogenic treatment, the grain structure of the material can be significantly refined, and the grains can be induced to rotate and rearrange, which helps to form twin structures, thereby improving the strength and hardness of the material. In addition, deep cryogenic treatment helps to reduce the residual stress in the material, reduces the stress concentration area caused by rapid cooling and processing, thereby improving the toughness and impact resistance of the material, further enhancing its fatigue resistance. Deep cryogenic treatment also causes slight changes in the lattice constant of the material, promoting the precipitation of second-phase particles. Such changes in microstructure help to improve the overall stability and wear resistance of the alloy. Therefore, the deep cryogenic treatment in step 3 plays a key role in the microstructure control of the material, through the effects of grain refinement, twin formation, and reduction of residual stress, etc., so that the additive manufacturing GH4169 high-temperature alloy parts have more excellent physical properties and more stable organizational basis in the subsequent heating treatment process, thereby significantly improving the performance of the material in severe service environments.

[0038] In step 4, the heating treatment is to heat to 700-750℃ and keep for 6-9h; after the 700-750℃ holding is completed, cool to 600-650℃ at a cooling rate of 30-50℃ / h and keep for 6-9h; after the 600-650℃ holding is completed, fill with argon to cool to room temperature. The purpose of this process is to release the stress concentration points generated during the deep cryogenic treatment process by moderate heating, and promote the transformation of some hard and brittle phases that are broken or precipitated during the deep cryogenic process into more stable and dispersed particles, thereby improving the toughness and fatigue resistance of the material. In addition, this heating treatment can further stabilize the grain structure inside the material, avoid the increase in brittleness caused by excessive refinement after deep cryogenic treatment, and restore the grains to the best state by heating, which helps to maintain a small and uniform organizational structure, thereby enhancing the durability of the material under high temperature and complex stress conditions.

[0039] In the cryogenic treatment described in Step 5, the cooling rate is 5-10℃ / min, and the temperature is cooled to -130 to -180℃ and held for 24-48h. The purpose of this process is to promote more significant rotation and rearrangement of the grain structure in the material through a second cryogenic treatment, which further increases the twin crystals and other strengthening structures, thereby improving the hardness and strength of the material. In addition, the repetition of cryogenic treatment can reduce the residual stress that may be generated in the previous heating process, making the internal structure of the material more stable, while reducing the risk of internal stress concentration, improving the impact resistance and toughness of the material. The second cryogenic treatment can also further promote the precipitation and distribution of the second phase particles, increase the stability and wear resistance of the alloy, and thus make the material perform more excellently in high temperature and high stress environments.

[0040] In the heating treatment described in Step 6, the temperature is raised to 700-750℃ and held for 6-9h; after the holding at 700-750℃, the temperature is cooled to 600-650℃ at a cooling rate of 30-50℃ / h and held for 6-9h; after the holding at 600-650℃, argon is filled to cool to room temperature. The core function of this process is to further homogenize the microstructure produced after cryogenic treatment by moderate heat treatment, so that the residual stress and unevenness in the material are completely eliminated. At the same time, the heating treatment helps to make the fine and brittle phase precipitated in the previous cryogenic process stable again, so that it is uniformly distributed in the matrix, further improving the toughness and fatigue resistance of the material. In addition, this heating treatment can also optimize the grain structure of the material, making it further stable on the basis of the refinement after cryogenic treatment, forming uniform and fine grains, thereby enhancing the durability and creep resistance of the material in high temperature environments. Through the slow cooling process, the microcracks and potential defects in the material are minimized, so that the alloy has higher stability and stronger crack resistance.

[0041] Compared with gradient multiple cooling, the present scheme has significant advantages, including more significant grain refinement effect, more complete stress release, more uniform strengthening phase precipitation, simplified process flow, and improved low-temperature performance of the material. First, deep cryogenic treatment can promote grain rotation and rearrangement by making the material experience extremely low temperature environment in a short time, thereby forming fine grains and twin structures, and significantly improving the strength and hardness of the material. Gradient multiple cooling has insufficient driving force for grain refinement due to its slow cooling speed, and it is difficult to achieve the same effect. Second, through two deep cryogenic treatments, the residual stress generated during high-temperature heat treatment can be quickly eliminated after each treatment, thereby effectively reducing the brittleness of the material and improving its toughness. In contrast, the stress release effect of gradient cooling is not as complete as that of deep cryogenic treatment. Deep cryogenic treatment can also promote the precipitation of small strengthening phases (such as γ' phase and γ'' phase) in the alloy and make them more uniformly distributed in the matrix, thereby improving the wear resistance and creep resistance of the alloy. Gradient cooling may not result in sufficient precipitation of strengthening phases. In terms of process flow, although deep cryogenic treatment needs to be carried out at extremely low temperature, by concentrating on two deep cryogenic treatments, the overall heat treatment cycle can be shortened, avoiding the complex operation and control difficulty brought by multiple treatments, and improving production efficiency. Finally, deep cryogenic treatment gives the material higher low-temperature performance, making it perform more excellently in extreme temperature environments. Gradient cooling cannot achieve the same low-temperature strengthening effect. Therefore, compared with gradient multiple cooling, the present scheme significantly improves the mechanical properties and heat treatment efficiency of the additive manufacturing GH4169 high-temperature alloy by two deep cryogenic treatments, making the material have more excellent performance in both high-temperature and low-temperature environments. Embodiment

[0042] The heat treatment method of the additive manufacturing GH4169 high-temperature alloy material comprises the following steps:

[0043] (1) The additive manufacturing of GH4169 high-temperature alloy parts is carried out by laser powder bed fusion technology.

[0044] (2) The additive manufacturing GH4169 high-temperature alloy is placed in a hot isostatic pressing device for heat preservation and pressure treatment, with a temperature of 1200°C, a pressure of 140MPa, and a time of 1h.

[0045] (3) After the heat preservation and pressure treatment is completed, the pressure is reduced to 90MPa and argon is filled for cooling.

[0046] (4) When the pressure in the furnace is reduced to 28MPa, stop filling argon.

[0047] (5) When the furnace temperature is reduced to 290°C, start unloading until the pressure in the furnace is 0.

[0048] (6) The part after the heat preservation and pressure preservation treatment is placed in an argon furnace for aging treatment, heated to 750°C and preserved for 7h.

[0049] (7) After the heat preservation, the cooling rate is 30°C / h to cool to 650°C and preserved for 8h.

[0050] (8) After the heat preservation, argon is filled to cool to room temperature.

[0051] (9) The part after the aging treatment is placed in a deep cooling control box for cooling treatment, the cooling rate is 10°C / min, cooled to -160°C and preserved for 36h.

[0052] (10) The part after the deep cooling treatment is placed in an argon furnace for heating treatment, heated to 700°C and preserved for 9h.

[0053] (11) After the heat preservation, the cooling rate is 30°C / h to cool to 650°C and preserved for 6h.

[0054] (12) After the heat preservation, argon is filled to cool to room temperature.

[0055] (13) The part after the heating treatment is placed in a deep cooling control box for cooling treatment, the cooling rate is 10°C / min, cooled to -160°C and preserved for 36h.

[0056] (14) The part after the deep cooling treatment is placed in an argon furnace for heating treatment, heated to 700°C and preserved for 9h.

[0057] (15) After the heat preservation, the cooling rate is 30°C / h to cool to 650°C and preserved for 6h.

[0058] (16) After the heat preservation, argon is filled to cool to room temperature. Example

[0059] The heat treatment method of the GH4169 high-temperature alloy material of additive manufacturing comprises the following steps:

[0060] (1) The GH4169 high-temperature alloy part is manufactured by using the laser powder bed melting technology;

[0061] (2) The additive manufactured GH4169 high-temperature alloy is placed in a hot isostatic pressing device for heat preservation and pressure preservation treatment, the temperature is 1100°C, the pressure is 150MPa, and the time is 1h10min.

[0062] (3) After the heat preservation and pressure preservation, the pressure is reduced to 75MPa and argon is filled to cool.

[0063] (4) When the pressure in the furnace is reduced to 30MPa, stop filling argon.

[0064] (5) After the furnace is cooled to 260°C, pressure relief is started until the pressure in the furnace is 0.

[0065] (6) The part after the heat and pressure treatment is placed in an argon furnace for aging treatment, heated to 740°C and held for 6.5 h.

[0066] (7) After the holding is completed, the cooling is performed at a rate of 40°C / h to 620°C and held for 7 h.

[0067] (8) After the holding is completed, argon is filled to cool to room temperature.

[0068] (9) The part after the aging treatment is placed in a cryogenic control box for cooling treatment, at a cooling rate of 8°C / min, cooled to -180°C and held for 24 h.

[0069] (10) The part after the cryogenic treatment is placed in an argon furnace for heating treatment, heated to 750°C and held for 6 h.

[0070] (11) After the holding is completed, the cooling is performed at a rate of 50°C / h to 600°C and held for 9 h.

[0071] (12) After the holding is completed, argon is filled to cool to room temperature.

[0072] (13) The part after the heating treatment is placed in a cryogenic control box for cooling treatment, at a cooling rate of 8°C / min, cooled to -180°C and held for 24 h.

[0073] (14) The part after the cryogenic treatment is placed in an argon furnace for heating treatment, heated to 750°C and held for 6 h.

[0074] (15) After the holding is completed, the cooling is performed at a rate of 50°C / h to 600°C and held for 9 h.

[0075] (16) After the holding is completed, argon is filled to cool to room temperature. Example

[0076] The heat treatment method of the GH4169 high-temperature alloy material manufactured by additive manufacturing comprises the following steps:

[0077] (1) The GH4169 high-temperature alloy part is manufactured by additive manufacturing using laser powder bed melting technology;

[0078] (2) The GH4169 high-temperature alloy manufactured by additive manufacturing is placed in a hot isostatic pressing device for heat and pressure treatment, at a temperature of 1250°C, a pressure of 130 MPa, and a time of 50 min.

[0079] (3) After the heat and pressure treatment is completed, the pressure is reduced to 95 MPa and argon is filled to cool.

[0080] (4) When the pressure in the furnace is reduced to 27 MPa, stop the argon gas charging.

[0081] (5) When the furnace is cooled to 290℃, start the pressure relief until the pressure in the furnace is 0.

[0082] (6) Put the workpiece after the heat preservation and pressure maintaining treatment into the argon furnace for aging treatment, heat to 700℃ and keep for 9h.

[0083] (7) After the heat preservation, cool to 600℃ at a cooling rate of 35℃ / h and keep for 9h.

[0084] (8) After the heat preservation, charge the argon gas and cool to room temperature.

[0085] (9) Put the workpiece after the aging treatment into the cryogenic control box for cooling treatment, the cooling rate is 8℃ / min, cool to -130℃ and keep for 48h.

[0086] (10) Put the workpiece after the cryogenic treatment into the argon furnace for heating treatment, heat to 730℃ and keep for 7h.

[0087] (11) After the heat preservation, cool to 610℃ at a cooling rate of 50℃ / h and keep for 8h.

[0088] (12) After the heat preservation, charge the argon gas and cool to room temperature.

[0089] (13) Put the workpiece after the heating treatment into the cryogenic control box for cooling treatment, the cooling rate is 8℃ / min, cool to -130℃ and keep for 48h.

[0090] (14) Put the workpiece after the cryogenic treatment into the argon furnace for heating treatment, heat to 730℃ and keep for 7h.

[0091] (15) After the heat preservation, cool to 610℃ at a cooling rate of 50℃ / h and keep for 8h.

[0092] (16) After the heat preservation, charge the argon gas and cool to room temperature.

[0093] The above only describes the preferred embodiments of the present application and is not used to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A heat treatment method for improving the mechanical properties of an additively manufactured GH4169 superalloy part, characterized in that, It comprises the following steps: S1, the additive manufacturing GH4169 high temperature alloy parts are put into the hot isostatic pressing equipment for heat preservation and pressure treatment; S2, the additive manufacturing GH4169 high temperature alloy parts obtained in step S1 are put into a vacuum heat treatment furnace for aging treatment; S3, the additive manufacturing GH4169 high temperature alloy parts obtained in step S2 are put into a deep cooling control box for deep cooling treatment; S4, the additive manufacturing GH4169 high temperature alloy parts obtained in step S3 are put into a vacuum heat treatment furnace for heating treatment; S5, the additive manufacturing GH4169 high temperature alloy parts obtained in step S4 are put into a deep cooling control box for deep cooling treatment; S6, the additive manufacturing GH4169 high temperature alloy parts obtained in step S5 are put into a vacuum heat treatment furnace for heating treatment; In step S1, the temperature of heat preservation and pressure treatment in the hot isostatic pressing equipment is 1100-1250℃, the pressure is 130MPa-150MPa, and the time is 1h±15min; In step S1, after the heat preservation and pressure treatment is completed, the pressure is first reduced to below 100MPa, then argon is filled to cool down, and when the pressure in the furnace is reduced to below 31MPa, the filling of argon is stopped. In step S1, when the furnace is cooled to below 300℃, the pressure is started to be released until the pressure in the furnace is 0.

2. The heat treatment method for improving the mechanical properties of additive manufacturing GH4169 high temperature alloy parts according to claim 1, characterized in that: In step S2, the temperature of the vacuum heat treatment furnace is raised to 700-750℃, and then heat preservation is carried out for 6-9h; After the heat preservation at 700-750℃ is completed, cooling is carried out at a cooling rate of 30-50℃ / h to 600-650℃, and then heat preservation is carried out for 6-9h.

3. The heat treatment method for improving the mechanical properties of additive manufacturing GH4169 high temperature alloy parts according to claim 2, characterized in that: In step S2, after the heat preservation at 600-650℃ is completed, argon is filled to cool to room temperature.

4. The heat treatment method for improving the mechanical properties of additive manufacturing GH4169 high temperature alloy parts according to claim 1, characterized in that: In the deep cooling treatment of step 3, the cooling rate is 5-10℃ / min, and after cooling to -130--180℃, heat preservation is carried out for 24-48h.

5. The heat treatment method for improving the mechanical properties of additive manufacturing GH4169 high temperature alloy parts according to claim 1, characterized in that: In the heating treatment of step 4, after being raised to 700-750℃, heat preservation is carried out for 6-9h; After the heat preservation at 700-750℃ is completed, cooling is carried out at a cooling rate of 30-50℃ / h to 600-650℃, and then heat preservation is carried out for 6-9h; After the heat preservation at 600-650℃ is completed, argon is filled to cool to room temperature.

6. The heat treatment method for improving the mechanical properties of additive manufacturing GH4169 high temperature alloy parts according to claim 1, characterized in that: In the cryogenic treatment described in step 5, the cooling rate is 5-10℃ / min, and the temperature is kept at -130 to -180℃ for 24-48 hours.

7. The heat treatment method for improving the mechanical properties of an additive manufacturing GH4169 superalloy part according to claim 1, characterized in that: In the heating treatment described in step 6, the temperature is kept at 700-750℃ for 6-9 hours; After the temperature holding at 700-750℃ is completed, the temperature is cooled to 600-650℃ at a cooling rate of 30-50℃ / h, and the temperature is kept for 6-9 hours; After the temperature holding at 600-650℃ is completed, argon is filled to cool the temperature to room temperature.