A gh4093 high temperature alloy forging and method of manufacturing the same

Abstract

The present application relates to a kind of GH4093 high-temperature alloy forgings and its manufacturing method, belong to metal processing technical field.The manufacturing method includes the following steps: vacuum induction smelting, using Ni-B alloy optimization refining process, improve the purity of liquid steel and composition uniformity;Vacuum consumable melting, further purify metal, improve crystalline structure, reduce segregation;Forging breakdown, after upsetting, drawing and multiple back furnace heating, prepare high-quality blank;Forging into material, adopt optimized process and forge out the size head structure forging blank;Heat treatment, by solid solution and aging treatment, significantly improve grain structure and mechanical properties.The chemical composition of the obtained forging includes: C:0.05%-0.08%, Cr:18.0%-21.0%, Co:15.0%-21.0%, Al:1.0%-2.0%, Ti:2.0%-3.0%, B:≤0.02%, the balance is Ni and impurities.The manufacturing method of the present application is advanced, and the quality of product is stable, significantly improves the comprehensive performance and size precision of the prepared forging, meets the demand of high-end field such as aviation, nuclear energy and other complex structure high-temperature alloy forgings.

Description

Technical Field

[0001] This invention relates to the field of metal processing technology, and more specifically, to a GH4093 high-temperature alloy forging and its manufacturing method. Background Technology

[0002] GH4093 is a precipitation-strengthened nickel-based superalloy widely used in aerospace applications, including turbine disks, turbine blades, and other high-temperature components. This material exhibits excellent high-temperature creep resistance, oxidation resistance, and fatigue resistance, maintaining good strength and stability even at temperatures ranging from 600°C to 800°C. However, the manufacturing process of GH4093 alloy forgings still faces the following technical challenges and limitations in the current technology:

[0003] Controlling compositional uniformity is challenging: GH4093 alloy contains various high-melting-point elements (such as Cr, Co, Mo, and W), which are prone to segregation during smelting and forging, leading to uneven compositional distribution. This segregation directly affects the alloy's mechanical properties and high-temperature stability, especially noticeable in large-sized forgings. Current smelting and heat treatment methods are insufficient to completely eliminate this segregation.

[0004] Influence of forging process parameters on grain size control: Grain size is a key factor affecting the overall performance of high-temperature alloy forgings. Fine and uniform grains can significantly improve the high-temperature strength, creep properties, and ductility of materials. However, in existing forging processes, improper control of temperature and deformation rate may lead to grain growth or uneven deformation, thereby affecting the high-temperature performance of the material.

[0005] The contradiction between mechanical properties and grain size: In existing processes, grain refinement is usually required to achieve high strength. However, excessive grain refinement may reduce the plasticity and toughness of the material, thus limiting the service life of forgings under complex stress conditions. Therefore, achieving the optimal balance between strength and plasticity is a major technical challenge in the production of GH4093 forgings.

[0006] Limitations of heat treatment processes: During solution treatment and aging treatment of GH4093 alloy forgings, precise control of temperature and holding time is required to ensure the full precipitation and uniform distribution of strengthening phases (such as γ' phase). However, existing heat treatment processes often fail to simultaneously achieve grain refinement, stress relief, and optimized precipitate distribution, resulting in significant fluctuations in the mechanical properties of the forgings.

[0007] The conflict between dimensional accuracy and defect control: In existing technologies, the large-scale manufacturing of GH4093 forgings is prone to dimensional deviations and surface defects such as cracks and oxide scale. These defects not only affect subsequent processing but also significantly reduce the reliability of the forgings.

[0008] In summary, existing technologies for manufacturing GH4093 alloy forgings suffer from problems such as poor compositional uniformity, insufficient grain size control, unstable mechanical properties, and difficulty in controlling dimensions and surface quality. These issues severely limit the further application of this material in high-end fields such as aerospace. Therefore, there is an urgent need to develop an optimized manufacturing method to achieve high performance and high reliability of GH4093 alloy forgings, providing a better solution for complex high-temperature operating conditions. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a manufacturing method for GH4093 high-temperature alloy forgings, so as to solve the problems of uneven grain structure, unstable mechanical properties and difficulty in forming complex structure forgings in the conventional manufacturing methods of the prior art.

[0010] To overcome the shortcomings of the prior art, the present invention provides a method for manufacturing GH4093 high-temperature alloy forgings, characterized by comprising the following steps:

[0011] S1: Vacuum induction smelting electrode rod;

[0012] Metallic Cr, metallic Co, and electrolytic Ni are loaded into a vacuum induction furnace, vacuumed, and energized to melt the raw materials. Then, metallic Al and metallic Ti are added for refining. After refining, samples are taken to analyze the chemical composition. When the chemical composition is qualified, Ni-B alloy is added, and refining is continued before steel is tapped. The molten steel is poured into an ingot mold and cooled to room temperature to obtain an electrode rod.

[0013] S2: Vacuum self-consumable steel ingot production;

[0014] After the surface of the electrode rod is polished to a metallic luster, it is placed in a vacuum arc remelting furnace, vacuumed and energized to melt it, thus completing the vacuum arc remelting process and obtaining a steel ingot with high purity and low segregation.

[0015] S3: Forging blanking;

[0016] After the surface of the steel ingot is polished, it is placed into a heating furnace, heated and held at a certain temperature before being taken out of the furnace. The steel ingot is first upset on a forging machine, and then drawn into a square billet. After being held in the furnace for 1 hour, it is taken out of the furnace again and forged into a round bar. After forging, it is air-cooled to room temperature.

[0017] S4: Forged finished product;

[0018] The round bar billet is cut into blanks; the blanks are loaded into a heating furnace, heated and kept warm, and then taken out of the furnace and forged into square billets on a forging equipment; after being taken out of the furnace and kept warm, they are first drawn into square billets, and then further forged into forging blanks with a large and small end structure, wherein the cross-sectional dimensions of the large end and the small end are connected by a transition area. After forging, the blanks are air-cooled to room temperature.

[0019] S5: Heat treatment;

[0020] Solution treatment: The forging blank is placed in a heating furnace for solution treatment;

[0021] Aging treatment: The solution-treated forging blank is put back into the heating furnace for aging treatment.

[0022] Compared with the prior art, the manufacturing method of GH4093 high-temperature alloy forgings provided in this application has the following advantages:

[0023] Precise control of composition and microstructure uniformity: The manufacturing method in this invention significantly improves the purity and composition uniformity of molten steel by combining vacuum induction melting with Ni-B alloy optimization process; vacuum self-consumption further reduces segregation problems;

[0024] Precision forming of high-performance forgings: By optimizing the forging process and adopting a combination of multiple reheating, upsetting and drawing steps, the problem of forming complex-shaped forgings has been successfully solved, ensuring the high quality and dimensional accuracy of the blanks for large and small end forgings.

[0025] Significantly improved mechanical properties: The manufacturing method in this invention obtains a uniform grain structure through precise solution treatment and aging heat treatment. The mechanical property test results (such as room temperature tensile and high temperature creep properties) show that the forgings fully meet the technical standard requirements and have stable and reliable performance.

[0026] The manufacturing method of this invention employs a high-vacuum environment and step-by-step temperature-controlled heat treatment, which ensures that strengthening elements (such as Al and Ti) are uniformly distributed and fully dissolved in the alloy, effectively improving the high-temperature performance and service stability of the forgings, while ensuring the machinability and surface quality of complex structures. Through innovative process design and precise parameter control, not only is the segregation problem in the prior art solved, but also the efficient manufacturing of high-strength, high-plasticity, and complex-structured GH4093 high-temperature alloy forgings is achieved, providing a reliable guarantee for applications in high-end fields such as aerospace and nuclear power.

[0027] In one possible implementation, after step S5, step S6, sampling inspection and machining and flaw detection, is further included, including:

[0028] S6: Sampling inspection, machining, and flaw detection:

[0029] After the large end of the forging is cut off, a sample is taken to test the chemical composition, room temperature tensile properties, and high temperature creep properties to ensure that the performance of the forging meets the technical standards. Then, the qualified forging is machined and the excess part is cut off according to the size requirements. The forging is then subjected to ultrasonic testing according to the GB / T4162 standard to obtain the finished forging.

[0030] Compared with existing technologies, the above-mentioned technical solution, by removing the large end of the forging and sampling key areas (such as half the radius of the cross-section), can representatively inspect the internal structure uniformity and mechanical properties of the forging, ensuring that the quality of the final product meets stringent technical standards. Surface finishing eliminates oxide layers and defects from the processing, and combined with ultrasonic testing to detect latent defects, effectively eliminating potential problems such as internal cracks and inclusions, thereby improving the service safety and reliability of the forging. The above implementation method, through standardized sampling, physicochemical testing, and flaw detection procedures, significantly improves the overall performance stability and reliability of the forging, providing strong quality assurance for high-temperature service in downstream applications.

[0031] In one possible implementation, the conditions for vacuuming and electro-melting in step S1 are: vacuuming to ≤1.0 Pa and electro-melting to ≥1520℃.

[0032] Compared with existing technologies, the above-mentioned technical solution effectively eliminates residual oxygen, nitrogen and other impurity gases in the furnace by evacuating to ≤1.0 Pa, reducing the impact of dissolved gases on the purity of the molten steel and avoiding uneven composition caused by oxide inclusions and nitride formation. By electrifying the molten steel to a temperature ≥1520℃, the metal raw materials are fully melted, providing an optimal reaction temperature range for the subsequent addition of alloying elements (such as Al and Ti), avoiding uneven distribution of alloying elements due to insufficient temperature. Furthermore, at high temperatures above 1520℃, the metal raw materials are completely melted and form a uniform molten steel, reducing the possibility of local component segregation and laying the foundation for subsequent refining and alloy composition adjustment. Ultimately, it provides high-quality initial materials for subsequent processes, ensuring that the mechanical properties and service reliability of the forgings fully meet the technical requirements of high-end application fields.

[0033] In one possible implementation, in step S1, the refining time is greater than or equal to 1 hour, and the continued refining time is 10-15 minutes.

[0034] Compared with existing technologies, the above-mentioned technical solution, which sets the refining time to be greater than or equal to 1 hour, can fully remove dissolved gases (such as O, N, H) and volatile impurities from the molten steel, while also ensuring the complete separation of inclusions from the slag and molten metal, thereby improving the purity of the molten steel. Continuing the refining process for another 10-15 minutes provides a sufficient time window for key alloying elements (such as Al, Ti, Ni-B) to be evenly distributed in the molten steel and to react completely with residual impurities (such as oxygen), avoiding compositional deviations or impurity residues caused by insufficient reaction. By adding Ni-B alloy after refining and controlling the refining time to 10-15 minutes, it is possible to ensure uniform dissolution of B element, avoiding excessive volatilization or over-reaction of B due to prolonged refining, thereby optimizing the distribution of the strengthening phase and the grain structure of the alloy.

[0035] In one possible implementation, in step S2, the vacuuming condition is that the vacuum level inside the furnace is ≤0.1 Pa.

[0036] Compared with existing technologies, the above-mentioned technical solution effectively balances the needs of impurity volatilization and alloy element protection through a high vacuum environment of ≤0.1Pa, reducing the problems of impurity residue or element loss in traditional processes. This technical solution ensures the purity and compositional uniformity of steel ingots while providing a reliable foundation for the high performance of forgings. It is particularly suitable for high-performance alloy materials operating under extreme high-temperature conditions, further enhancing the advancement of the manufacturing process and the competitiveness of the materials.

[0037] In one possible implementation, in step S3, the furnace loading temperature of the billet is ≤600℃, and the heating and holding conditions are: heating for 5 hours to 1100±10℃ and holding for 5 hours.

[0038] Compared with existing technologies, the above technical solution, by controlling the furnace charging temperature of the billet to ≤600℃, reducing the furnace charging temperature and controlling the heating rate, can significantly reduce the amount of oxide scale generated on the surface of the billet during the heating process, further reducing the impact of oxide scale removal on production efficiency. It can effectively avoid thermal shock caused by excessive temperature difference between the billet and the furnace, thereby reducing the generation of surface cracks and internal thermal stress in the billet. The slow heating process of 5 hours to 1100±10℃ gradually reduces the temperature difference between the inside and outside of the billet, ensuring that the entire billet reaches a uniform heating state, providing stable material conditions for subsequent forging. Under the holding temperature of 1100±10℃, the recrystallization process of the billet can be fully carried out, the grains are refined and uniformly distributed, which helps to improve the plasticity and toughness of the metal.

[0039] In one possible implementation, in step S4, the furnace loading temperature of the billet is ≤600℃, and the heating and holding conditions are: heating to 1100±10℃, holding for 4 hours, and the furnace return holding time is 1 hour.

[0040] Compared with existing technologies, the above technical solution effectively reduces the temperature difference between the billet and the furnace by controlling the furnace loading temperature to ≤600℃, avoiding cracks and internal stress concentration caused by thermal shock, and ensuring the structural integrity of the billet during heating. Heating to 1100±10℃ and holding for 4 hours ensures that the billet reaches the optimal temperature required for forging, which helps improve the plasticity of the metal and reduces local stress caused by internal temperature differences. Under the condition of holding in the furnace for 1 hour, the internal stress and temperature gradient after the initial forging are eliminated, so that the billet has a better microstructure during further forging, reducing the formation of cracks or other defects during reprocessing. By strictly controlling the holding time, the problem of grain coarsening caused by excessive holding time is avoided, while ensuring that grain homogenization is promoted during heating and holding, thus enhancing the comprehensive mechanical properties of the material.

[0041] In one possible implementation, in step S5, the conditions for the solution treatment are: heating the blank to 1060±10℃ and holding it for 8 hours, then removing it from the furnace and air-cooling it to room temperature; the conditions for the aging treatment are: heating the blank to 710±10℃ and holding it for 12 hours, then removing it from the furnace and air-cooling it to room temperature.

[0042] Compared with the existing technology, the above technical solution heats the blank to 1060±10℃ during the solution treatment process, reaching the dissolution temperature of the alloy strengthening phase, so that the main strengthening elements (such as Ti and Al) in the alloy dissolve uniformly in the matrix, eliminating segregation and uneven microstructure, and providing a uniform microstructure basis for subsequent aging treatment. The aging treatment heats the blank to 710±10℃ and holds it for 12 hours, providing sufficient time for the strengthening phase (including Ni3(Ti,Al)) to precipitate uniformly and be refined in the matrix. This precipitation strengthening mechanism significantly improves the high-temperature strength and creep resistance of forgings; air cooling after solution treatment effectively avoids stress concentration and cracking risks caused by rapid cooling, while refining grains; by combining solution treatment and aging treatment, the heat treatment process of forgings is precisely controlled, taking into account the comprehensive optimization of strength, toughness and fatigue resistance, which is particularly suitable for manufacturing key structural components with high temperature and high strength requirements: aging treatment further stabilizes the crystal structure, reduces internal stress and enhances the dimensional stability of forgings, the optimized design of dual heat treatment eliminates micro-defects that may remain in the solution treatment process, and the high temperature resistance and fatigue resistance of forgings are improved by aging treatment, especially exhibiting excellent mechanical properties and creep strength at a high temperature of 800℃.

[0043] The technical problem to be solved by the present invention is to provide a manufacturing method for GH4093 high-temperature alloy forgings, so as to solve the problem of unstable mechanical properties of forgings prepared by conventional manufacturing methods in the prior art.

[0044] To overcome the shortcomings of the prior art, the present invention provides a GH4093 high-temperature alloy forging, wherein the chemical composition of the forging is: C: 0.05%-0.08%, Si: ≤0.1%, Mn: ≤0.1%, P: ≤0.015%, S: ≤0.005%, Cr: 18.0%-21.0%, Co: 15.0%-21.0%, Al: 1.0%-2.0%, Ti: 2.0%-3.0%, B: ≤0.02%, Fe: ≤1.0%, with the balance being Ni and other unavoidable impurities.

[0045] Compared with existing technologies, the GH4093 high-temperature alloy forging disclosed in this application has the following advantages: The GH4093 high-temperature alloy forging of this invention, through optimized vacuum induction smelting and vacuum arc remelting processes, combined with precise addition of Ni-B alloy and efficient refining measures, effectively reduces the content of impurities (such as S and P) in the molten steel, while stabilizing the proportions of key elements (such as Al, Ti, and B), significantly improving the room temperature tensile properties and high-temperature creep rupture properties of the forging. Furthermore, the manufacturing method employs a step-by-step heating, upsetting, and drawing forging process, first forming a uniform square billet, and then further forging it into a large-and-small-head structure blank, effectively overcoming the cracking and uneven microstructure problems caused by the narrow forging temperature range of high-temperature alloys. Ultimately, it achieves a comprehensive improvement in the mechanical properties and dimensional accuracy of the forging. Through solution treatment and aging heat treatment processes, and by precisely controlling the temperature (1060℃ and 710℃) and holding time (8 hours and 12 hours respectively), the forging achieves a comprehensive improvement in the mechanical properties and dimensional accuracy of the forging. The invention achieves uniform precipitation of strengthening phases and refinement of matrix grains, significantly improving the high-temperature creep resistance and ductility of forgings. Through reasonable component ratios (including optimized ratios of C and Co), combined with high-purity molten steel and precise forging processes, the GH4093 forgings prepared by this invention significantly outperform existing technologies in terms of room temperature tensile properties, high-temperature creep resistance, and fatigue resistance, meeting the stringent requirements of high-temperature materials in high-end fields such as aerospace and nuclear power. By strictly controlling each process condition from vacuum smelting to forging, segregation and internal stress in the forgings are significantly reduced. At the same time, the flaw detection process is optimized to ensure that the flaw detection pass rate of finished forgings reaches the A-level standard, further improving the consistency and reliability of the products. This invention effectively solves the problems of uneven component distribution, grain coarsening, and unstable performance existing in the prior art, providing a reliable process guarantee and technical route for the production of high-performance GH4093 high-temperature alloy forgings.

[0046] In one possible embodiment, the chemical composition of the forging is: C: 0.062%, Si: 0.06%, Mn: 0.052%, S: 0.0021%, P: 0.004%, Cr: 19.73%, Co: 17.32%, Al: 1.57%, Ti: 2.75%, B: 0.007%, Fe: 0.36%, with the balance being Ni and other unavoidable impurities.

[0047] Compared with existing technologies, the above-mentioned technical solution further optimizes the chemical composition of the forgings, ensuring the carbon content is at an optimal level of 0.062%, strengthening the matrix structure, and avoiding brittleness caused by excessive carbon. Optimization of silicon and manganese content improves the deoxidation and grain refinement effects of the molten steel, further enhancing the high-temperature strength and toughness of the forgings. Furthermore, strictly controlling the sulfur and phosphorus contents to 0.0021% and 0.004% respectively significantly reduces grain boundary segregation and crack sensitivity, improving the corrosion resistance and high-temperature service stability of the forgings. The Cr and Co contents are maintained at [specific levels]. The 19.73% and 17.32% content ensures excellent oxidation resistance and high-temperature strength. Meanwhile, the titanium content of 2.75% optimizes the precipitation effect of the strengthening phase and significantly improves the creep resistance of the forging. The optimization of aluminum and boron content (1.57% and 0.007%) balances matrix strengthening and crack resistance, significantly improving the comprehensive mechanical properties of the forging. Through the above composition optimization, the service reliability of the prepared GH4093 high-temperature alloy forging in high-temperature environments is significantly improved, which can meet the requirements of high-end fields such as aviation and nuclear power for the consistency and long-term stability of material properties. Detailed Implementation

[0048] First, those skilled in the art should understand that these embodiments are merely used to explain the technical principles of the embodiments of this application and are not intended to limit the scope of protection of the embodiments of this application. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0049] This invention provides a method for manufacturing GH4093 high-temperature alloy forgings, comprising the following steps:

[0050] S1: Vacuum induction smelting electrode rod;

[0051] Metallic Cr, metallic Co, and electrolytic Ni are loaded into a vacuum induction furnace, vacuumed, and energized to melt the raw materials. Then, metallic Al and metallic Ti are added for refining. After refining, samples are taken to analyze the chemical composition. When the chemical composition is qualified, Ni-B alloy is added, and refining is continued before steel is tapped. The molten steel is poured into an ingot mold and cooled to room temperature to obtain an electrode rod.

[0052] S2: Vacuum self-consumable steel ingot production;

[0053] After the surface of the electrode rod is polished to a metallic luster, it is placed in a vacuum arc remelting furnace, vacuumed and energized to melt it, thus completing the vacuum arc remelting process and obtaining a steel ingot with high purity and low segregation.

[0054] S3: Forging blanking;

[0055] After the surface of the steel ingot is polished, it is placed into a heating furnace, heated and held at a certain temperature before being taken out of the furnace. The steel ingot is first upset on a forging machine, and then drawn into a square billet. After being held in the furnace for 1 hour, it is taken out of the furnace again and forged into a round bar. After forging, it is air-cooled to room temperature.

[0056] S4: Forged finished product;

[0057] The round bar billet is cut into blanks; the blanks are loaded into a heating furnace, heated and kept warm, and then taken out of the furnace and forged into square billets on a forging equipment; after being taken out of the furnace and kept warm, they are first drawn into square billets, and then further forged into forging blanks with a large and small end structure, wherein the cross-sectional dimensions of the large end and the small end are connected by a transition area. After forging, the blanks are air-cooled to room temperature.

[0058] S5: Heat treatment;

[0059] Solution treatment: The forging blank is placed in a heating furnace for solution treatment;

[0060] Aging treatment: The solution-treated forging blank is put back into the heating furnace for aging treatment.

[0061] As a preferred embodiment, after step S5, step S6, sampling inspection, machining, and flaw detection, is further included, including:

[0062] S6: Sampling inspection, machining, and flaw detection:

[0063] After the large end of the forging is cut off, a sample is taken to test the chemical composition, room temperature tensile properties, and high temperature creep properties to ensure that the performance of the forging meets the technical standards. Then, the qualified forging is machined and the excess part is cut off according to the size requirements. The forging is then subjected to ultrasonic testing according to the GB / T4162 standard to obtain the finished forging.

[0064] The manufacturing method of the present invention uses a 1600-ton high-speed forging machine to produce GH4093 large and small end forgings, which overcomes the problem of the narrow forging temperature range of this alloy. It produces GH4093 high-temperature alloy large and small end forgings with qualified mechanical properties in two forgings. The forging material is forged into large and small ends in one forging. The process design and forging operation are innovative.

[0065] As a preferred embodiment, in step S1, the conditions for vacuuming and powering to melt are: vacuuming to ≤1.0 Pa and powering to melt the steel to a temperature ≥1520℃.

[0066] As a preferred embodiment, in step S1, the refining time is greater than or equal to 1 hour, and the continued refining time is 10-15 minutes.

[0067] As a preferred embodiment, in step S2, the vacuuming condition is that the vacuum level inside the furnace is ≤0.1 Pa.

[0068] As a preferred embodiment, in step S3, the furnace loading temperature of the billet is ≤600℃, and the heating and holding conditions are: heating for 5 hours to 1100±10℃, and holding for 5 hours.

[0069] As a preferred embodiment, in step S4, the furnace loading temperature of the billet is ≤600℃, and the heating and holding conditions are: heating to 1100±10℃, holding for 4 hours, and the furnace return holding time is 1 hour.

[0070] As a preferred embodiment, in step S5, the conditions for the solution treatment are: heating the blank to 1060±10℃ and holding it for 8 hours, then removing it from the furnace and air-cooling it to room temperature; the conditions for the aging treatment are: heating the blank to 710±10℃ and holding it for 12 hours, then removing it from the furnace and air-cooling it to room temperature.

[0071] The present invention also provides a GH4093 high-temperature alloy forging, wherein the chemical composition of the forging is: C: 0.05%-0.08%, Si: ≤0.1%, Mn: ≤0.1%, P: ≤0.015%, S: ≤0.005%, Cr: 18.0%-21.0%, Co: 15.0%-21.0%, Al: 1.0%-2.0%, Ti: 2.0%-3.0%, B: ≤0.02%, Fe: ≤1.0%, with the balance being Ni and other unavoidable impurities.

[0072] As a preferred embodiment, the chemical composition of the forging is: C: 0.062%, Si: 0.06%, Mn: 0.052%, S: 0.0021%, P: 0.004%, Cr: 19.73%, Co: 17.32%, Al: 1.57%, Ti: 2.75%, B: 0.007%, Fe: 0.36%, with the balance being Ni and other unavoidable impurities.

[0073] The following explanation and description, in conjunction with specific data, further elaborates on the scope of the technical solution of the present invention:

[0074] Example 1

[0075] This embodiment provides a GH4093 high-temperature alloy forging and its manufacturing method. The chemical composition of the GH4093 high-temperature alloy forging is as follows:

[0076] C: 0.062%, Si: 0.06%, Mn: 0.052%, S: 0.0021%, P: 0.004%, Cr: 19.73%, Co: 17.32%, Al: 1.57%, Ti: 2.75%, B: 0.007%, Fe: 0.36%, balance Ni and other unavoidable impurities.

[0077] The manufacturing process steps are as follows:

[0078] S1: Vacuum induction smelting electrode rod

[0079] Metallic Cr, metallic Co, and electrolytic Ni were loaded into a vacuum induction furnace. After evacuating to ≤1.0 Pa, electricity was applied for melting. Once the metals were completely melted and the temperature reached 1520℃, metallic Al and metallic Ti were added for refining for 1 hour. After refining, samples were taken for chemical composition analysis. If the chemical composition was found to be acceptable, a Ni-B alloy was added, and refining continued for 10 minutes before tapping the steel. The molten steel was poured into a Φ440mm ingot mold, cooled for 2 hours, demolded, and air-cooled to room temperature to obtain the electrode rod.

[0080] S2: Vacuum self-consumable steel ingot production

[0081] After the surface of the electrode rod is polished to a metallic luster, it is placed in a vacuum arc remelting furnace, vacuumed to ≤0.1Pa, and then energized to melt, completing the vacuum arc remelting process and obtaining a Φ508mm steel ingot with high purity and low segregation.

[0082] S3: Forging blank

[0083] After the steel ingot surface is polished to its actual size of Φ485mm, it is placed in a natural gas heating furnace and heated to 1100℃ for 5 hours, then held at that temperature for 5 hours before being removed from the furnace. Using a 5000-ton high-speed forging mill, the steel ingot is first upset to half its original height, then drawn into a 500mm×500mm square billet, returned to the furnace for holding for 1 hour, and then forged again into a Φ420mm round bar. After forging, it is air-cooled to room temperature, completing the forging and billet opening process.

[0084] S4: Forged finished product

[0085] The Φ420mm round bar billet was cut at a rate of 970kg / piece, with a blank size of Φ420mm×855mm. The billet was then returned to the electric heating furnace and heated to 1100℃ for 5 hours, held at that temperature for 4 hours, and then forged into a 300mm×300mm×1315mm square billet on a 1600-ton high-speed forging mill. After being returned to the furnace and held at that temperature for 1 hour, it was drawn to a 235mm×235mm square billet, then chamfered at 385mm from the end, and forged into a Φ135mm×1482mm billet. It was then turned and forged into a Φ235mm×2150mm forging blank, with final dimensions of Φ235mm×2150mm + Φ135mm×1482mm. After forging, it was air-cooled to room temperature.

[0086] S5: Heat Treatment

[0087] Solution treatment: The forging blank is placed in an electric heating furnace, heated to 1060°C and held for 8 hours, and then removed from the furnace and air-cooled to room temperature.

[0088] Aging treatment: The solution-treated forging blank is put back into the electric heating furnace, heated to 710℃ and held for 12 hours, and then removed from the furnace and air-cooled to room temperature.

[0089] S6: Sampling Inspection and Machining Flaw Detection

[0090] After removing 100mm from the large end of the forging, a 60mm long sample was cut for testing its chemical composition, room temperature tensile properties, and high temperature creep rupture properties. After passing the performance tests, the forging surface was machined and sized. Surface machining began after the forging passed the physical and chemical tests, and was carried out according to… Figure 1 After removing the excess portion to meet dimensional requirements, the finished forging dimensions are Φ225*1950+Φ135*1182mm, with a total length of 3132mm. Figure 1 As shown, Figure 1 This shows the final dimensions of the forging obtained in Example 1 and a schematic diagram of the forging.

[0091] Ultrasonic testing was performed on the forgings in accordance with the GB / T4162 standard to ensure that the testing met the Class A standard, and finally the finished forgings were obtained.

[0092] The mechanical properties of the forgings obtained in Example 1 above were tested, and the results are shown in the table below:

[0093] Table 1:

[0094]

[0095] Example 2

[0096] This embodiment provides a GH4093 high-temperature alloy forging and its manufacturing method. The chemical composition of the GH4093 high-temperature alloy forging is as follows:

[0097] C: 0.05%, Si: 0.1%, Mn: 0.1%, S: 0.005%, P: 0.015%, Cr: 18.0%, Co: 15.0%, Al: 1.0%, Ti: 2.0%, B: 0.02%, Fe: 1.0%, with the balance being Ni and other unavoidable impurities.

[0098] The manufacturing method includes:

[0099] S1: Vacuum induction smelting electrode rod

[0100] Metallic Cr, metallic Co, and electrolytic Ni were loaded into a vacuum induction furnace and evacuated to ≤1.0 Pa. Electricity was applied to melt the metals until they were completely melted and the temperature reached 1530℃. Then, metallic Al and metallic Ti were added for refining, which lasted for 1 hour. After refining, samples were taken for chemical composition analysis. Once the chemical composition was deemed acceptable, a Ni-B alloy was added, and refining continued for another 15 minutes before tapping the steel. The molten steel was poured into a Φ440mm ingot mold, cooled for 2 hours, and then demolded and air-cooled to room temperature to obtain the electrode rod.

[0101] S2: Vacuum self-consumable steel ingot production

[0102] After polishing the surface of the electrode rod to a metallic luster, it is placed in a vacuum arc remelting furnace, evacuated to ≤0.1Pa, and then energized to melt, completing the vacuum arc remelting process to obtain a Φ508mm steel ingot with high purity and low segregation.

[0103] S3: Forging blank

[0104] After the steel ingot surface is polished to its actual size of Φ485mm, it is placed in a natural gas heating furnace and heated to 1090℃ for 5 hours, then held at that temperature for 5 hours before being removed from the furnace. Using a 5000-ton high-speed forging mill, the steel ingot is first upset to half its original height, then drawn into a 500mm×500mm square billet, returned to the furnace for holding for 1 hour, and then forged again into a Φ420mm round bar. After forging, it is air-cooled to room temperature, completing the forging and billet opening step.

[0105] S4: Forged finished product

[0106] The Φ420mm round bar billet was cut at a rate of 970kg / piece, with a blank size of Φ420mm×855mm. The billet was then returned to the electric heating furnace and heated to 1090℃ for 5 hours, held at that temperature for 4 hours, and then forged into a 300mm×300mm×1315mm square billet on a 1600-ton high-speed forging mill. After being returned to the furnace and held at that temperature for 1 hour, it was drawn to a 235mm×235mm square billet, then chamfered at 385mm from the end, and forged into a Φ135mm×1482mm billet. It was then turned and forged into a Φ235mm×2150mm forging blank, with final dimensions of Φ235mm×2150mm + Φ135mm×1482mm. After forging, it was air-cooled to room temperature.

[0107] S5: Heat Treatment

[0108] Solution treatment: The forging blank is placed in an electric heating furnace, heated to 1055°C and held for 8 hours, and then removed from the furnace and air-cooled to room temperature.

[0109] Aging treatment: The solution-treated forging blank is put back into the electric heating furnace, heated to 705℃ and held for 12 hours, and then removed from the furnace and air-cooled to room temperature.

[0110] S6: Sampling Inspection and Machining Flaw Detection

[0111] After removing 100mm from the large end of the forging, a 60mm long sample was cut for testing its chemical composition, room temperature tensile properties, and high temperature creep rupture properties. After passing the performance tests, the forging surface was machined, and excess material was removed according to the finished product dimensions. Ultrasonic testing was then performed on the forging according to GB / T4162 standard to ensure it met the Class A standard, ultimately yielding the finished forging.

[0112] Example 3

[0113] This embodiment provides a GH4093 high-temperature alloy forging and its manufacturing method. The chemical composition of the GH4093 high-temperature alloy forging is as follows:

[0114] C: 0.08%, Si: 0.08%, Mn: 0.09%, S: 0.004%, P: 0.014%, Cr: 21.0%, Co: 20.0%, Al: 2.0%, Ti: 3.0%, B: 0.015%, Fe: 0.8%, balance Ni and other unavoidable impurities.

[0115] The manufacturing method includes:

[0116] S1: Vacuum induction smelting electrode rod

[0117] Metallic Cr, metallic Co, and electrolytic Ni were loaded into a vacuum induction furnace and evacuated to ≤1.0 Pa. Electricity was applied to melt the metals until they were completely melted and the temperature reached 1525℃. Then, metallic Al and metallic Ti were added for refining, which lasted for 1 hour. After refining, samples were taken for chemical composition analysis. Once the chemical composition was deemed acceptable, a Ni-B alloy was added, and refining continued for another 12 minutes before tapping the steel. The molten steel was poured into a Φ440mm ingot mold, cooled for 2 hours, and then demolded and air-cooled to room temperature to obtain the electrode rod.

[0118] S2: Vacuum self-consumable steel ingot production

[0119] After polishing the surface of the electrode rod to a metallic luster, it is placed in a vacuum arc remelting furnace, evacuated to ≤0.1Pa, and then energized to melt, completing the vacuum arc remelting process to obtain a Φ508mm steel ingot with high purity and low segregation.

[0120] S3: Forging blank

[0121] After the steel ingot surface is polished to its actual size of Φ485mm, it is placed in a natural gas heating furnace and heated to 1110℃ for 5 hours, then held at that temperature for 5 hours before being removed from the furnace. Using a 5000-ton high-speed forging mill, the steel ingot is first upset to half its original height, then drawn into a 500mm×500mm square billet, returned to the furnace for holding for 1 hour, and then forged again into a Φ420mm round bar. After forging, it is air-cooled to room temperature, completing the forging and billet opening step.

[0122] S4: Forged finished product

[0123] The Φ420mm round bar billet was cut at a rate of 970kg / piece, with a blank size of Φ420mm×855mm. The billet was then returned to the electric heating furnace and heated to 1110℃ for 5 hours, held at that temperature for 4 hours, and then forged into a 300mm×300mm×1315mm square billet on a 1600-ton high-speed forging mill. After being returned to the furnace and held at that temperature for 1 hour, it was drawn to a 235mm×235mm square billet, then chamfered at 385mm from the end, and forged into a Φ135mm×1482mm billet. It was then turned around and forged into a Φ235mm×2150mm forging blank, with final dimensions of Φ235mm×2150mm + Φ135mm×1482mm. After forging, it was air-cooled to room temperature.

[0124] S5: Heat Treatment

[0125] Solution treatment: The forging blank is placed in an electric heating furnace, heated to 1070°C and held for 8 hours, and then removed from the furnace and air-cooled to room temperature.

[0126] Aging treatment: The solution-treated forging blank is put back into the electric heating furnace, heated to 720℃ and held for 12 hours, and then removed from the furnace and air-cooled to room temperature.

[0127] S6: Sampling Inspection and Machining Flaw Detection

[0128] After removing 100mm from the large end of the forging, a 60mm long sample was cut for testing its chemical composition, room temperature tensile properties, and high temperature creep rupture properties. After passing the performance tests, the forging surface was machined, and excess material was removed according to the finished product dimensions. Ultrasonic testing was then performed on the forging according to GB / T4162 standard to ensure it met the Class A standard, ultimately yielding the finished forging.

[0129] The above embodiments further demonstrate that the present invention provides a GH4093 high-temperature alloy forging and its manufacturing method. This method solves several key problems existing in the background art through the following technical principles:

[0130] Component uniformity control:

[0131] This invention employs vacuum induction smelting combined with an optimized Ni-B alloy refining process, significantly reducing the content of impurities (such as S and P) in the molten steel, suppressing segregation, and ensuring the precise proportions and uniform distribution of key elements (such as Cr, Co, Ti, and Al). Simultaneously, vacuum arc refining further purifies the metal, improving the crystal structure of the steel ingot and avoiding the mechanical property fluctuations caused by compositional inhomogeneity in conventional processes.

[0132] Forging process optimization:

[0133] The manufacturing method of this invention ensures the uniformity of grain size in the forging blank by precisely controlling the forging temperature and employing multiple heating cycles, combined with upsetting and drawing processes. This avoids the cracking and grain coarsening problems caused by the narrow temperature range in traditional processes. In particular, the combination of multiple reheating cycles and gradual deformation enhances the internal consistency of the material and the dimensional accuracy of the final product.

[0134] Enhanced phase precipitation control:

[0135] The manufacturing method of this invention combines solution treatment and aging treatment. Through precise temperature and holding time design (solution treatment temperature 1060±10℃, holding time 8 hours; aging treatment temperature 710±10℃, holding time 12 hours), it achieves uniform precipitation of reinforcing phases (such as Ni3(Ti,Al)) and refinement of matrix grains, which significantly improves the high-temperature strength and creep resistance of the material.

[0136] Unstable mechanical properties:

[0137] The manufacturing method of this invention optimizes the refining process and heat treatment parameters, which significantly improves the room temperature tensile properties of the forgings. The measured values ​​show that the yield strength (σ0.2) is 728 MPa, the tensile strength (σb) is 1123 MPa, and the elongation (δ5) is 27%, all of which are higher than the technical standard requirements (≥700 MPa, ≥1100 MPa, ≥20%), indicating that the forgings have excellent strength and plasticity matching at room temperature.

[0138] Insufficient reliability during high-temperature service:

[0139] Regarding the creep performance under high temperature conditions of 800℃, the forging prepared by this invention has a fracture time of 46 hours under stress of 300 MPa, which is significantly better than the standard requirement of 30 hours. At the same time, the elongation under high temperature conditions reaches 18.5%, further verifying the superior performance and stability of the material under high temperature and high stress conditions.

[0140] Grain coarsening and dimensional accuracy:

[0141] The manufacturing method of this invention optimizes the solution treatment and aging processes, controlling grain refinement while maintaining uniform distribution, thus eliminating the brittleness problem caused by grain growth. Furthermore, the synergistic optimization of forging and heat treatment significantly improves the dimensional accuracy of the finished forgings, ensuring the shape stability of complex structures (forgings with different end sizes), and meeting the stringent quality requirements of high-end fields such as aerospace and nuclear power.

[0142] In summary, through comprehensive optimization of composition, microstructure, and mechanical properties, this invention not only solves the problems of compositional segregation, mechanical property fluctuations, and insufficient high-temperature service stability existing in the prior art, but also achieves a significant improvement in the mechanical properties, dimensional accuracy, and overall service performance of forgings, providing a reliable guarantee for the application of GH4093 high-temperature alloy forgings in high-end fields such as aerospace and nuclear power.

[0143] In the description of this application, the references to terms such as "an embodiment," "some embodiments," "in this embodiment," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0144] 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 manufacturing a GH4093 high-temperature alloy forging, characterized in that, Includes the following steps: S1: Vacuum induction smelting electrode rod; Metallic Cr, metallic Co, and electrolytic Ni are loaded into a vacuum induction furnace as raw materials, a vacuum is drawn and electricity is supplied to melt the raw materials; then metallic Al and metallic Ti are added for refining. After refining, samples are taken to analyze the chemical composition. When the chemical composition is qualified, Ni-B alloy is added, and refining is continued before steel is tapped; the molten steel is poured into an ingot mold and cooled to room temperature to obtain the electrode rod; S2: Vacuum self-consumable steel ingot production; After polishing the surface of the electrode rod to a metallic luster, it is placed into a vacuum self-consumable furnace, vacuumed and electrically melted to complete the vacuum self-consumable remelting process, and a steel ingot with high purity and low segregation is obtained. S3: Forging and billet preparation; After polishing the surface of the steel ingot, it is placed into a heating furnace, heated and held at a certain temperature, and then taken out of the furnace; On the forging equipment, the steel ingot is first upset, and then drawn into a square billet; After being held in the furnace for 1 hour, it is taken out of the furnace again and forged into a round bar, and then air-cooled to room temperature after forging; S4: Forging into finished product; The round bar billet is cut into blanks; The cut billet is loaded into a heating furnace, heated and kept at a certain temperature, and then taken out of the furnace and forged into a square billet on a forging equipment; After being reheated in the furnace, the forged blank is first drawn into a square billet, and then further forged into a forged blank with a large and small end structure. The cross-sectional dimensions of the large end and the small end are connected by a transition area. After forging, the blank is air-cooled to room temperature; S5: Heat treatment; Solution treatment: The forged blank is added to a heating furnace for solution treatment; Aging treatment: The solution-treated forged blank is put back into the heating furnace for aging treatment; In step S3, the furnace loading temperature of the billet is ≤600℃, and the heating and holding conditions are: heating for 5 hours to 1100±10℃ and holding for 5 hours. In step S4, the furnace loading temperature of the billet is ≤600℃, and the heating and holding conditions are: heating to 1100±10℃, holding for 4 hours, and the furnace holding time is 1 hour. In step S5, the conditions for solution treatment are: heating the blank to 1060±10℃ and holding it for 8 hours, then removing it from the furnace and air-cooling it to room temperature; the conditions for aging treatment are: heating the blank to 710±10℃ and holding it for 12 hours, then removing it from the furnace and air-cooling it to room temperature. The finished forging of the GH4093 high-temperature alloy has dimensions of Φ225mm*1950mm+Φ135mm*1182mm and a total length of 3132mm.

2. The method for manufacturing the GH4093 high-temperature alloy forging according to claim 1, characterized in that, After step S5, step S6, sampling inspection and machining and flaw detection, is also included, including: S6: Sampling inspection and machining and flaw detection: After the large end of the forging is cut off, a sample is taken to test the chemical composition, room temperature tensile properties, and high temperature creep properties to ensure that the performance of the forging meets the technical standards. Then, the qualified forging is machined and the excess part is cut off according to the size requirements. The forging is subjected to ultrasonic flaw detection according to the GB / T4162 standard to obtain the finished forging.

3. The method for manufacturing the GH4093 high-temperature alloy forging according to claim 1, characterized in that, In step S1, the conditions for vacuuming and electric melting are: vacuuming to ≤1.0 Pa and electric melting to ≥1520℃.

4. The method for manufacturing the GH4093 high-temperature alloy forging according to claim 1, characterized in that, In step S1, the refining time is greater than or equal to 1 hour, and the refining time is 10-15 minutes.

5. The method for manufacturing the GH4093 high-temperature alloy forging according to claim 1, characterized in that, In step S2, the vacuuming condition is that the vacuum level inside the furnace is ≤0.1 Pa.

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