A superalloy ingot homogenization smelting method and ultra-thin foil

Abstract

This application belongs to the field of high-temperature alloy smelting technology, and particularly relates to a method for homogenizing high-temperature alloy ingots and an ultra-thin foil. The embodiments of this application achieve carbide dispersion and refinement and uniform distribution of alloying elements throughout the entire process through multi-stage synergistic regulation, including the construction of a vacuum low-pollution environment, safe and efficient heating, high-temperature homogenization and carbide re-dissolution, medium-speed first-stage cooling to prevent rapid carbide growth, low-speed second-stage cooling to promote carbide dispersion and precipitation, and furnace cooling to maintain microstructure stability. This solves the technical problem of how to achieve homogenized smelting of high-temperature alloy ingots and control carbide distribution during the annealing stage based on steady-state melting rate control. It can suppress secondary precipitation and aggregation of carbides during annealing, improving the microstructure uniformity and carbide controllability of high-temperature alloy ingots.

Description

Technical Field

[0001] This application belongs to the field of high-temperature alloy smelting technology, and particularly relates to a method for homogenizing high-temperature alloy ingots and ultra-thin foil materials. Background Technology

[0002] High-temperature alloys possess excellent high-temperature strength, corrosion resistance, and creep resistance, and are widely used in sealing components of high-end power equipment such as aero engines and gas turbines. With the development of lightweight and precision equipment, the demand for ultra-thin high-temperature alloy strips with a thickness of ≤0.05mm has surged. The uniformity of the foil structure and the morphology of the carbides directly determine the sealing accuracy and service life of the sealing components.

[0003] High-temperature alloy carbides exhibit significant microstructural inheritance, and defects such as ingot segregation and coarse carbides are difficult to eliminate through subsequent rolling. Therefore, homogenization control during the ingot smelting stage is crucial for the preparation of high-performance ultrathin foils.

[0004] Current smelting processes are mostly designed for conventional plates and bars, lacking homogenization and carbide control technologies suitable for ultra-thin strips. This makes it difficult to balance compositional uniformity and refined carbide control, resulting in numerous ingot microstructure defects and failing to meet the mass production and service requirements of ultra-thin sealing foils. Specific defects of existing processes are as follows: 1. Severe compositional segregation and significant inherited defects. The large fluctuations in melting rate during single vacuum induction melting make it easy for high-density elements such as chromium, molybdenum, and tungsten to produce dendritic segregation and gravity segregation, resulting in uneven ingot composition. These defects are inherited by the finished foil, creating structural defects.

[0005] 2. Carbides are difficult to control, resulting in poor service performance. Conventional processes lack pre-process carbon control measures, and coarse carbides easily precipitate during alloy solidification. Due to genetic effects, these carbides remain inside the foil, disrupting the matrix continuity and reducing high-temperature resistance and mechanical properties.

[0006] 3. External impurities cause contamination and low alloy purity. Ordinary refractory crucibles have low purity and insufficient protection in the melting atmosphere, allowing carbon and oxygen impurities to easily penetrate the melt and form secondary carbides, exacerbating the unevenness of the microstructure and failing to meet the high purity requirements of high-end foil materials.

[0007] 4. Insufficient sealing performance limits application. Defects in the raw materials make ultra-thin foils prone to carbide shedding and intergranular corrosion under high-temperature conditions, leading to uncontrolled sealing gaps, air leakage, and failure, making them unsuitable for the harsh operating conditions of high-end equipment.

[0008] In summary, existing smelting processes suffer from severe segregation, coarse carbides, and low purity. The industry urgently needs to develop a homogenization smelting method for ingots that is suitable for ultra-thin foil materials, optimize the ingot structure from the source, make up for the performance shortcomings of ultra-thin sealing foil materials, and meet the mass production and service requirements of high-end equipment. Summary of the Invention

[0009] This application provides a method for homogenizing the smelting of high-temperature alloy ingots and an ultra-thin foil to solve the following technical problem: how to achieve homogenizing the smelting of high-temperature alloy ingots and control carbides based on steady-state control of melting rate.

[0010] In a first aspect, embodiments of this application provide a method for homogenizing high-temperature alloy ingots, the method comprising: The raw materials are pretreated to obtain pretreated raw materials; the raw materials include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and carbide stabilizer titanium, wherein the amount of chromium added is 21.0~23.0 wt%, the amount of iron added is 17.00~19.00 wt%, the amount of cobalt added is 0.50~1.50 wt%, the amount of molybdenum added is 8.0~10.0 wt%, the amount of tungsten added is 0.2~0.8 wt%, the amount of manganese added is 0.2~0.8 wt%, the amount of titanium added is 0.08~0.12 wt%, and the balance is nickel; The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melting ingots. The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing process includes: in a vacuum degree ≤10 -2 Under the condition of Pa, the temperature is increased to 1160℃~1200℃ at a heating rate of 8℃ / min~10℃ / min and held for 15h~25h. Then, the temperature is decreased to 890℃~950℃ at a cooling rate of 6℃ / min~7℃ / min, and then decreased to 590℃~650℃ at a cooling rate of 2℃ / min~4℃ / min. Finally, the temperature is cooled to room temperature with the furnace. The annealed ingot is then subjected to double-sided machining and finishing to obtain a high-temperature alloy ingot. The single-sided cutting removal amount of the double-sided machining finishing is 0.20mm~0.30mm, and the surface roughness Ra of the high-temperature alloy ingot is ≤1.2μm.

[0011] Optionally, the raw material is a high-purity raw material with a purity of ≥99.95wt%; the pretreatment includes removing the oxide scale and oil stains on the surface of the raw material and vacuum drying the raw material.

[0012] Optionally, the vacuum degree of the vacuum induction melting is ≤5Pa; The vacuum induction melting process includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1450℃~1480℃, and the holding time is 30min~40min. The temperature of the high-temperature refining period is 1500℃~1550℃, and the holding time is 20min~25min.

[0013] Optionally, the electroslag remelting uses calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina and magnesium oxide is 6:3:1; The electroslag remelting current is 8000A~8500A, the voltage is 35V~40V, the melting rate is 2.0kg / min~2.5kg / min, the melting rate fluctuation is ±0.18kg / min, and the slag pool temperature is 1550℃~1600℃.

[0014] Optionally, in the annealed ingot after vacuum homogenization annealing, the average size of the carbides is ≤2μm, and the carbides are in a dispersed distribution state; The alloy element composition segregation degree in the annealed ingot after vacuum homogenization annealing is ≤ ±0.5%.

[0015] Optionally, the oxygen content in the high-temperature alloy ingot is ≤10ppm and the nitrogen content is ≤5ppm.

[0016] Optionally, the raw material further includes a carbon source, the content of which is 0.075wt%~0.095wt%.

[0017] Optionally, the carbon source is 0.085 wt% carbon, and the titanium content is 0.10 wt%; the vacuum degree of the vacuum induction melting is 0.5 Pa; the current of the electroslag remelting is 8200 A, the melting rate is 2.1 kg / min, and the melting rate fluctuation is ±0.15 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1170 °C, and the holding time is 18 h.

[0018] Optionally, the carbon source is 0.08 wt% carbon, and the amount of titanium added is 0.08 wt%; the vacuum degree of the vacuum induction melting is 0.8 Pa; the current of the electroslag remelting is 8000 A, the melting rate is 2.0 kg / min, and the melting rate fluctuation is ±0.18 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1160℃, and the holding time is 20 h.

[0019] Optionally, the carbon source is 0.09 wt% carbon, and the titanium content is 0.12 wt%; the vacuum degree of the vacuum induction melting is 0.2 Pa; the current of the electroslag remelting is 8500 A, the melting rate is 2.2 kg / min, and the melting rate fluctuation is ±0.12 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1180℃, and the holding time is 15 h.

[0020] Optionally, the high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled and solution-treated to obtain an ultra-thin foil with a thickness of ≤0.05mm. The thickness tolerance of the ultra-thin high-temperature alloy ingot is ±0.003mm, and it has excellent plate shape and no rolling breaks or microcracks.

[0021] In a second aspect, embodiments of this application provide an ultrathin high-temperature alloy ingot, which is prepared by the method described in any one of the first aspects; The average size of carbides in the ultrathin high-temperature alloy ingot is ≤2μm, the segregation degree of alloy element composition is ≤±0.5%, the oxygen content is ≤10ppm, the nitrogen content is ≤5ppm, and the carbides are in a dispersed distribution state.

[0022] The technical solution provided in this application has the following advantages compared with the prior art: An unreasonable cooling process is a major factor leading to the precipitation and aggregation of secondary carbides, the inability to achieve carbide dispersion and refinement, and consequently, the failure to meet the performance standards of ultra-thin rolling. Insufficient annealing temperature and holding time are important factors leading to insufficient diffusion of alloying elements and the inability to fully dissolve and disperse residual carbide clusters.

[0023] In this embodiment, an electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum degree is ≤10... -2 Vacuum homogenization annealing is performed under the condition of Pa. This vacuum condition can reduce the residual oxygen partial pressure and nitrogen partial pressure in the furnace, thereby avoiding oxidation and nitriding on the alloy surface during annealing, thus ensuring the surface quality and internal purity of the annealed ingot, and achieving a low-pollution annealing environment.

[0024] In this embodiment, the temperature is raised to 1160℃~1200℃ at a heating rate of 8℃ / min~10℃ / min. This heating rate avoids excessively rapid heating, which could lead to large temperature differences between the inside and outside of the ingot and cause thermal stress cracks. At the same time, it avoids excessively slow heating, which could lead to low production efficiency. This ensures that the electroslag remelted ingot is heated uniformly and reaches the target annealing temperature steadily, providing stable thermal field conditions for subsequent alloy element diffusion and carbide re-dissolution, thus achieving safe and efficient heating.

[0025] In this embodiment, the alloy is held at 1160℃~1200℃ for 15h~25h. This holding temperature is higher than the complete remelting temperature of the carbides and lower than the overheating temperature of the alloy. This holding time ensures that the alloying elements are fully diffused and homogenized, and promotes the complete remelting and dispersing of residual carbide clusters, thereby completely eliminating dendrite segregation and gravity segregation, achieving full dissolution of carbide clusters, and thus achieving uniform distribution of alloying elements throughout the entire domain and high dispersion of carbide precursors, achieving high-temperature homogenization and carbide remelting.

[0026] In this embodiment, the temperature is then reduced to 890°C to 950°C at a rate of 6°C / min to 7°C / min. This first-stage cooling rate is controlled within a medium-speed range, and the termination temperature of this first-stage cooling is above the carbide precipitation sensitive temperature range. This prevents rapid precipitation and growth of carbides at higher temperatures, providing highly dispersed nucleation sites for subsequent controllable carbide precipitation, thus achieving carbide precipitation regulation.

[0027] In this embodiment, the temperature is further reduced to 590°C to 650°C at a cooling rate of 2°C / min to 4°C / min. This second-stage cooling rate is controlled in a low-speed range, and the termination temperature of this second-stage cooling is lower than the rapid growth temperature range of carbides. This promotes the precipitation of carbides in a fine and dispersed form in the lower temperature range, avoids the aggregation and growth of carbides and the formation of continuous grain boundary segregation, and achieves carbide dispersion and refinement.

[0028] In the embodiments of this application, the ingot is cooled to room temperature in the furnace. Furnace cooling avoids the thermal stress generated by forced cooling, ensures the stability of the annealed ingot structure and maintains the achieved carbide dispersion distribution, guarantees the subsequent processing performance of the annealed ingot, and achieves stress-free cooling.

[0029] In summary, this vacuum homogenization annealing treatment achieves carbide dispersion and refinement and uniform distribution of alloying elements across the entire range through multi-stage coordinated control, including constructing a vacuum low-pollution environment, realizing safe and efficient heating, achieving full homogenization and carbide re-dissolution at high temperature, using medium-speed first-stage cooling to prevent rapid carbide growth, using low-speed second-stage cooling to promote carbide dispersion and precipitation, and maintaining microstructure stability through furnace cooling. This solves the technical problem of how to achieve homogenization smelting of high-temperature alloy ingots and control carbide in the annealing stage based on steady-state control of melting rate. It can suppress secondary precipitation and aggregation of carbides during annealing, and improve the microstructure uniformity and carbide controllability of high-temperature alloy ingots. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0031] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the accompanying drawings required in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other related drawings can be derived from these drawings without creative effort.

[0032] Figure 1 This is a metallographic image of the high-temperature alloy ingot in Example 1 of this application; Figure 2 The image shows the metallographic structure of the high-temperature alloy ingot in Comparative Example 1 of this application. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0034] The range descriptions used herein, such as numerical ranges and proportional ranges, include all possible sub-ranges and single numerical values ​​within the range. For example, a range description of 1 to 6 or 1~6 covers all sub-ranges (such as 1 to 3, 2 to 5, etc.) and single numbers (such as 1, 2, 3, 4, 5, 6) between 1 and 6. Unless otherwise specified, the terms used herein include, but are not limited to, terms such as "include"; relational terms such as "first" and "second" are used only to distinguish different entities or steps and do not imply an actual order or relationship; and / or indicate that multiple situations may exist alone or simultaneously; expressions such as "at least one," "multiple," and "at least one" refer to any combination of the corresponding objects, including combinations of single or multiple objects. Proportional relationships mentioned herein, such as mass ratios and molar ratios, should be understood as the correspondence between the antecedent and consequent terms of a proportional expression, according to the order of description. The raw materials, reagents, instruments, and equipment used herein can all be obtained through commercial purchase or prepared using existing methods.

[0035] In a first aspect, embodiments of this application provide a method for homogenizing high-temperature alloy ingots, the method comprising: S1. The raw materials are pretreated to obtain pretreated raw materials; the raw materials include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese and carbide stabilizer titanium, wherein the amount of chromium added is 21.0~23.0 wt%, the amount of iron added is 17.00~19.00 wt%, the amount of cobalt added is 0.50~1.50 wt%, the amount of molybdenum added is 8.0~10.0 wt%, the amount of tungsten added is 0.2~0.8 wt%, the amount of manganese added is 0.2~0.8 wt%, the amount of titanium added is 0.08~0.12 wt%, and the balance is nickel; S2. The pretreated raw material is subjected to vacuum induction melting under an argon protective atmosphere to obtain a vacuum induction melting ingot. S3. Electroslag remelting is performed on the vacuum induction melting ingot to obtain an electroslag remelted ingot; S4. The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing process includes: in a vacuum degree ≤10 -2Under the condition of Pa, the temperature is increased to 1160℃~1200℃ at a heating rate of 8℃ / min~10℃ / min and held for 15h~25h. Then, the temperature is decreased to 890℃~950℃ at a cooling rate of 6℃ / min~7℃ / min, and then decreased to 590℃~650℃ at a cooling rate of 2℃ / min~4℃ / min. Finally, the temperature is cooled to room temperature with the furnace. S5. The annealed ingot is double-sided machined and finished to obtain a high-temperature alloy ingot. The single-sided cutting removal amount of the double-sided machining finishing is 0.20mm~0.30mm, and the surface roughness Ra of the high-temperature alloy ingot is ≤1.2μm.

[0036] In this embodiment, titanium carbide stabilizer refers to titanium element added to the raw material to inhibit carbide coarsening and promote carbide dispersion. In this embodiment, melting rate fluctuation refers to the variation in the weight of the molten raw material per unit time during vacuum induction melting. In this embodiment, vacuum induction melting ingot refers to the intermediate ingot product obtained by vacuum induction melting of pretreated raw materials under an argon protective atmosphere. In this embodiment, electroslag remelting ingot refers to the refined ingot product obtained by electroslag remelting of a vacuum induction melting ingot. In this embodiment, double-sided micro-milling finishing refers to a finishing process in which micro-milling is performed on the two opposite surfaces of an annealed ingot to remove surface defects.

[0037] The innovative approach of this vacuum homogenization annealing technology compared to existing technologies lies in the fact that existing technologies use natural cooling for annealing without step-by-step temperature control, leaving the problem of secondary carbide precipitation and aggregation unresolved. In contrast, the embodiments of this application construct a five-stage vacuum homogenization annealing process consisting of heating, holding, medium-speed cooling in the first stage, low-speed cooling in the second stage, and furnace cooling. This process decomposes the cooling process into two different rate stages, achieving precise control of carbide precipitation kinetics through the rate difference. Together with the aforementioned melting rate fluctuation control, this forms a closed-loop steady-state control from melting to annealing, completely blocking the genetic amplification path of carbides from coarse clusters to dispersed refinement.

[0038] Cr (chromium) includes, but is not limited to (wt%): 21.0%, 21.5%, 22.0%, 22.5%, 23.0%; Fe (iron) includes, but is not limited to (wt%): 17.00%, 17.50%, 18.00%, 18.50%, 19.00%; Co (cobalt) includes, but is not limited to (wt%): 0.50%, 0.75%, 1.00%, 1.25%, 1.50%; Mo (molybdenum) includes, but is not limited to (wt%): 8.0%, 8.5%, 9.0%, 9.5%, 10.0%; W (tungsten) includes, but is not limited to (wt%): 0.2%, 0.4%, 0.5%, 0.7%, 0.8%; Mn (manganese) includes, but is not limited to (wt%): 0.2%, 0.4%, 0.5%, 0.7%, 0.8%; the amount of titanium carbide stabilizer added includes, but is not limited to: 0.08wt%, 0.09wt%, 0.10wt%, 0.11wt%, 0.12wt%, etc. The vacuum degree of vacuum homogenization annealing is not limited to 1×10 -2 Pa, 5×10 -3 Pa, 1×10 -3 Pa, etc. The heating rate of the vacuum homogenization annealing process includes, but is not limited to, 8℃ / min, 9℃ / min, 10℃ / min, etc. The holding temperature of the vacuum homogenization annealing process includes, but is not limited to, 1160℃, 1170℃, 1180℃, etc. The holding time of the vacuum homogenization annealing process includes, but is not limited to, 15h, 16h, 17h, 18h, 19h, 20h, etc. The cooling rate of the first stage of the vacuum homogenization annealing process includes, but is not limited to, 6℃ / min, 7℃ / min, etc. The cooling termination temperature of the first stage of the vacuum homogenization annealing process includes, but is not limited to, 890℃, 900℃, 910℃, etc. The cooling rate of the second stage of the vacuum homogenization annealing process includes, but is not limited to, 2℃ / min, 3℃ / min, 4℃ / min, etc. The cooling termination temperature of the second stage of the vacuum homogenization annealing process includes, but is not limited to, 590℃, 600℃, 610℃, etc. The single-sided milling amount for double-sided micro-milling finishing includes, but is not limited to, 0.20mm, 0.22mm, 0.25mm, 0.26mm, 0.27mm, and 0.28mm. The surface roughness Ra of the finished casting billet includes, but is not limited to, 0.8μm, 1.0μm, and 1.2μm.

[0039] In some embodiments, the raw material is a high-purity raw material with a purity of ≥99.95wt%; the pretreatment includes removing oxide scale and oil stains from the surface of the raw material and vacuum drying the raw material.

[0040] In this embodiment, high-purity raw materials refer to raw materials with a purity ≥ 99.95 wt%. In this embodiment, vacuum drying refers to a pretreatment operation of drying the raw materials under vacuum conditions to remove moisture. Limiting the raw materials to high-purity raw materials with a purity ≥ 99.95 wt% reduces the impurity content inherent in the raw materials themselves, thereby reducing the probability of external impurities being introduced into the alloy during smelting, thus reducing the risk of secondary carbide precipitation and improving alloy purity. The pretreatment is limited to removing oxide scale and oil stains from the surface of the raw materials, followed by vacuum drying. Removing oxide scale prevents the introduction of additional oxygen elements during smelting, removing oil stains prevents the introduction of additional carbon elements during smelting, and vacuum drying removes adsorbed moisture from the raw materials, preventing the introduction of hydrogen and oxygen elements during smelting. This prevents external carbon and oxygen impurities from intruding into the smelting system, thereby avoiding the formation of secondary carbides and further deterioration of the microstructure uniformity.

[0041] In summary, this high-purity raw material and specific pretreatment process improve the purity of the raw material through source purification, thereby helping to solve the technical problem of how to achieve homogenized smelting of high-temperature alloy ingots and control of carbides based on steady-state control of melting rate.

[0042] In some embodiments, the vacuum degree of the vacuum induction melting is ≤5Pa; The vacuum induction melting process includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1450℃~1480℃, and the holding time is 30min~40min. The temperature of the high-temperature refining period is 1500℃~1550℃, and the holding time is 20min~25min.

[0043] In this embodiment, the low-temperature melting period refers to the stage in vacuum induction melting where the pretreated raw materials are held at a specific lower temperature for melting. In this embodiment, the high-temperature refining period refers to the stage in vacuum induction melting where the molten alloy is held at a specific higher temperature for refining. The vacuum degree of vacuum induction melting is controlled at ≤5 Pa. A low vacuum degree reduces the partial pressure of residual gas in the furnace, thereby reducing the probability of contact between gaseous impurities and the alloy liquid, and consequently reducing the degree of gas absorption and oxidation of the alloy liquid. Vacuum induction melting is configured to include a low-temperature melting period and a high-temperature refining period. The low-temperature melting period involves holding the material at a specific temperature for a specific time, allowing the pretreated raw materials to fully melt and initially homogenize, promoting the initial diffusion of alloying elements. The high-temperature refining period involves holding the material at a specific temperature for a specific time, allowing the alloy liquid to fully superheat and further homogenize, promoting the removal of inclusions by flotation, thereby ensuring that the alloy liquid reaches a fully homogenized and purified state, thus providing a high-quality vacuum induction melting ingot for subsequent electroslag remelting.

[0044] In summary, this segmented heat preservation vacuum induction melting process achieves gradual homogenization and refining of the alloy liquid through segmented temperature-time control, thereby helping to solve the technical problem of how to achieve homogenized smelting of high-temperature alloy ingots and control of carbides based on steady-state control of melting rate.

[0045] The vacuum degree of vacuum induction melting includes, but is not limited to, 2 Pa, 3 Pa, 4 Pa, and 5 Pa. The temperature during the low-temperature melting stage includes, but is not limited to, 1450℃, 1460℃, 1470℃, and 1480℃. The holding time during the low-temperature melting stage includes, but is not limited to, 30 min, 35 min, and 40 min. The temperature during the high-temperature refining stage includes, but is not limited to, 1500℃, 1510℃, and 1520℃. The holding time during the high-temperature refining stage includes, but is not limited to, 20 min, 22 min, and 25 min.

[0046] In some embodiments, the electroslag remelting uses calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina and magnesium oxide is 6:3:1; The current for electroslag remelting is 8000A~8500A, the voltage is 35V~40V, the melting rate is 2.0kg / min~2.5kg / min, the melting rate fluctuation is ≤±0.2kg / min, and the slag pool temperature is 1550℃~1600℃.

[0047] In this embodiment, the calcium fluoride-alumina-magnesium oxide refining slag refers to a special low-melting-point refining slag prepared from calcium fluoride, alumina, and magnesium oxide in a specific mass ratio and used in the electroslag remelting process. In this embodiment, the slag pool temperature refers to the temperature of the molten refining slag pool during the electroslag remelting process.

[0048] Electroslag remelting is carried out using calcium fluoride-alumina-magnesium oxide refining slag, with a mass ratio of calcium fluoride, alumina and magnesium oxide of 6:3:1. This ratio forms a low-melting-point, high-fluidity slag system. The low-melting-point slag system reduces the operating temperature of the slag pool, and the high-fluidity slag system enhances the reaction kinetics at the slag-metal interface, thereby improving the slag system's ability to adsorb and remove harmful impurities such as sulfur and phosphorus and promoting the flotation and separation of inclusions, thus improving the purity of the ingot. By controlling the current of electroslag remelting at 8000A~8500A, the voltage at 35V~40V, the melting rate at 2.0kg / min~2.5kg / min with a melting rate fluctuation of ≤±0.2kg / min, and the slag pool temperature at 1550℃~1600℃, the specific current and voltage matching generates a stable Joule heat input, the specific melting rate ensures stable advancement of the solidification front and avoids local overcooling, and the specific slag pool temperature maintains the slag system in the optimal reactivity range. This ensures the stable progress of the electroslag remelting process and completely eliminates dendritic segregation and gravity segregation in vacuum induction melting ingots, thereby achieving a uniform distribution of alloying elements throughout the entire process.

[0049] In summary, the special refining slag ratio and specific electroslag remelting parameters, through steady-state refining, deeply eliminate segregation, thereby helping to solve the technical problem of how to achieve homogenized smelting and carbide control of high-temperature alloy ingots based on steady-state melting rate control.

[0050] The current for electroslag remelting includes, but is not limited to, 8000A, 8200A, and 8500A. The voltage for electroslag remelting includes, but is not limited to, 35V, 37V, and 40V. The melting rate for electroslag remelting includes, but is not limited to, 2.0kg / min, 2.1kg / min, and 2.2kg / min. The slag pool temperature includes, but is not limited to, 1550℃, 1560℃, and 1570℃. The melting rate fluctuation for vacuum induction melting includes, but is not limited to, ±0.12kg / min, ±0.15kg / min, ±0.18kg / min, and ±0.20kg / min.

[0051] In some embodiments, the average size of the carbides in the annealed ingot after vacuum homogenization annealing is ≤2μm, and the carbides are in a dispersed distribution state. The alloy element composition segregation degree in the annealed ingot after vacuum homogenization annealing is ≤ ±0.5%.

[0052] In this embodiment, the average carbide size refers to the average equivalent diameter of carbide particles in the annealed ingot. In this embodiment, the dispersed distribution refers to the uniform dispersion of carbides in the alloy matrix, without local aggregation or continuous grain boundary segregation. In this embodiment, the alloy element composition segregation refers to the maximum deviation between the actual and target content of alloy elements in the annealed ingot. The annealed ingot after vacuum homogenization annealing is limited to an average carbide size ≤ 2 μm and a dispersed distribution. An average carbide size ≤ 2 μm ensures sufficiently fine carbide particles, and a dispersed distribution ensures no local aggregation or continuous grain boundary segregation, thereby eliminating the potential for carbides to act as stress concentration points and avoiding band breakage and microcracks caused by coarse or aggregated carbides during ultra-thin rolling. The annealed ingot after vacuum homogenization annealing is limited to an alloy element composition segregation degree of ≤±0.5%. An alloy element composition segregation degree of ≤±0.5% ensures that the alloy elements are highly uniform throughout the entire ingot, thereby completely eliminating dendritic segregation and specific gravity segregation, thus blocking the inheritance path of casting defects and ensuring the microstructure homogeneity of the ultrathin high-temperature alloy ingot.

[0053] In summary, the specific microstructure and composition indicators of this annealed ingot, through quantitative control of carbide morphology and compositional uniformity, directly verify the effectiveness of the solution to the technical problem of homogenized smelting and carbide control of high-temperature alloy ingots based on steady-state control of melting rate.

[0054] The average size of the carbides includes, but is not limited to, 1.2 μm, 1.5 μm, 1.8 μm, and 2.0 μm. The segregation of alloying elements includes, but is not limited to, ±0.2%, ±0.3%, ±0.4%, and ±0.5%.

[0055] In some embodiments, the oxygen content in the finished billet is ≤10ppm and the nitrogen content is ≤5ppm.

[0056] In this embodiment, oxygen content refers to the mass fraction of oxygen in the finished casting. In this embodiment, nitrogen content refers to the mass fraction of nitrogen in the finished casting. The finished casting is limited to an oxygen content ≤10ppm. An oxygen content ≤10ppm reduces the residual amount of oxygen in the finished casting, thereby reducing the probability of oxygen reacting with carbon and metallic elements in the alloy to form oxide inclusions, thus preventing oxide inclusions from becoming crack initiation sources and deteriorating the microstructure uniformity. The finished casting is limited to a nitrogen content ≤5ppm. A nitrogen content ≤5ppm reduces the residual amount of nitrogen in the finished casting, thereby reducing the probability of nitrogen reacting with metallic elements in the alloy to form nitride inclusions, thus preventing nitride inclusions from deteriorating the alloy's plasticity and surface quality.

[0057] In summary, the specific oxygen and nitrogen content of this finished billet ensures alloy purity by strictly controlling the content of gaseous impurities, thereby helping to solve the technical problem of how to achieve homogenized smelting and carbide control of high-temperature alloy ingots based on steady-state control of melting rate.

[0058] The oxygen content of the finishing billet includes, but is not limited to, 8 ppm, 9 ppm, and 10 ppm. The nitrogen content of the finishing billet includes, but is not limited to, 5 ppm, 4 ppm, and 3 ppm.

[0059] In some embodiments, the raw material further includes a carbon source, the content of which is 0.075wt% to 0.095wt%.

[0060] In this embodiment, the carbon source refers to the component added to the raw material to provide carbon. The raw material is defined as also including a carbon source, with a carbon source content of 0.075wt% to 0.095wt%. Within a specific content range, the carbon source provides the alloy with an appropriate amount of carbon. This appropriate amount of carbon reacts with the carbide stabilizer titanium to form stable carbides, thereby pre-inhibiting the nucleation and growth of coarse carbides, and thus achieving controllable carbide formation from the source.

[0061] The carbon source content is limited to the range of 0.075wt% to 0.095wt%. This range ensures that the carbon content meets the requirements for forming necessary carbides to strengthen the alloy, while avoiding excessive precipitation of carbides due to excessive carbon content, which would cause coarsening. Thus, under the synergistic effect of the carbide stabilizer titanium, the dispersion and refinement of carbides are controlled.

[0062] In summary, this specific carbon source, through its synergistic ratio with the carbide stabilizer titanium, achieves pre-suppression of carbides, thereby helping to solve the technical problem of how to achieve homogenized smelting and carbide control of high-temperature alloy ingots based on steady-state control of melting rate.

[0063] The carbon source content includes, but is not limited to, 0.075wt%, 0.080wt%, 0.085wt%, 0.090wt%, etc.

[0064] In some embodiments, the carbon source is 0.085 wt% carbon, and the titanium addition is 0.10 wt%; the vacuum degree of the vacuum induction melting is 3 Pa; the current of the electroslag remelting is 8200 A, the melting rate is 2.1 kg / min, and the melting rate fluctuation is ±0.15 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1170 °C, and the holding time is 18 h. Limiting the carbon source to 0.085 wt% carbon and the addition of titanium carbide stabilizer to 0.10 wt% creates an optimal synergy between the carbon source and the titanium carbide stabilizer. The titanium carbide stabilizer fully captures the carbon elements in the carbon source to form dispersed, fine, stable carbides, thereby maximizing the suppression of coarse carbide formation. Limiting the vacuum degree of the vacuum induction melting to 3 Pa further reduces the residual gas content, thereby further reducing the intrusion of gaseous impurities. The melting rate fluctuation in vacuum induction melting was limited to ±0.15 kg / min. This ±0.15 kg / min fluctuation further reduced the instability of the melting process, thereby further reducing the risk of segregation. The current for electroslag remelting was limited to 8200 A and the melting rate to 2.1 kg / min. This specific current and melting rate matching ensured that the electroslag remelting process was in the optimal steady-state range, thereby further eliminating residual segregation. The holding temperature for vacuum homogenization annealing was limited to 1170℃ and the holding time to 18 h. This specific temperature and time combination ensured that alloying elements were fully diffused and homogenized, and that carbide clusters were fully dissolved and dispersed, thereby further achieving carbide dispersion and refinement.

[0065] In some embodiments, the carbon source is 0.08 wt% carbon, and the titanium addition is 0.08 wt%; the vacuum degree of the vacuum induction melting is 4 Pa; the current of the electroslag remelting is 8000 A, the melting rate is 2.0 kg / min, and the melting rate fluctuation is ±0.18 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1160 °C, and the holding time is 20 h. Limiting the carbon source to 0.08 wt% carbon and the addition of titanium carbide stabilizer is a low-titanium fine-tuning scheme. The lower content of titanium carbide stabilizer matches the lower content of carbon source, allowing the titanium carbide stabilizer to still fully capture carbon elements in the carbon source to form stable carbides, thereby maintaining the carbide inhibition effect while reducing the amount of stabilizer used. Limiting the vacuum degree of the vacuum induction melting to 4 Pa ​​ensures a low residual gas environment. Limiting the melting rate fluctuation of the vacuum induction melting to ±0.18 kg / min maintains melting stability. The current for electroslag remelting was limited to 8000A and the melting rate to 2.0 kg / min. These specific parameters represent the lower limit of the steady-state range for electroslag remelting, thus ensuring refining effectiveness. The holding temperature for vacuum homogenization annealing was limited to 1160℃ and the holding time to 20h. The lower temperature combined with the longer holding time ensured sufficient diffusion of alloying elements, thereby further achieving homogenization.

[0066] In some embodiments, the carbon source is 0.09 wt% carbon, and the titanium addition is 0.12 wt%; the vacuum degree of the vacuum induction melting is 2 Pa, and the melting rate fluctuation is ±0.12 kg / min; the current of the electroslag remelting is 8500 A, the melting rate is 2.2 kg / min, and the melting rate fluctuation is ±0.12 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1180℃, and the holding time is 15 h. Limiting the carbon source to 0.09 wt% carbon and the addition of titanium carbide stabilizer to 0.12 wt% constitutes a high-titanium scheme. The higher content of titanium carbide stabilizer matches the higher content of carbon source, allowing the titanium carbide stabilizer to fully capture the carbon elements in the carbon source and form more dispersed and fine stable carbides, thereby further enhancing the carbide suppression effect. Limiting the vacuum degree of the vacuum induction melting to 2 Pa, the lower vacuum degree of 2 Pa minimizes the residual gas content, thereby minimizing the intrusion of gaseous impurities. The melting rate fluctuation in vacuum induction melting is limited to ±0.12 kg / min. This narrower fluctuation ensures melting stability to the greatest extent, thereby minimizing the risk of segregation. The current for electroslag remelting is limited to 8500 A and the melting rate to 2.2 kg / min. These specific parameters represent the upper limit of the steady-state range for electroslag remelting, ensuring efficient refining. The holding temperature for vacuum homogenization annealing is limited to 1180℃ and the holding time to 15 hours. The higher temperature combined with the shorter holding time achieves rapid homogenization, further improving production efficiency.

[0067] In some embodiments, the high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled and solution-treated to obtain an ultra-thin foil with a thickness of ≤0.05mm. The thickness tolerance of the ultra-thin foil is ±0.003mm, and it has excellent shape and no rolling breaks or microcracks.

[0068] In this embodiment, ultrathin foil refers to a high-temperature alloy strip product with a thickness ≤0.05mm obtained by rolling a finished cast billet. In this embodiment, thickness tolerance refers to the allowable deviation range between the actual thickness and the target thickness of the ultrathin foil. In this embodiment, rolling breakage refers to the phenomenon of high-temperature alloy strip breaking during the rolling process. In this embodiment, microcracks refer to tiny crack defects formed on or inside the surface of the ultrathin foil. The finished cast billet is rolled to obtain an ultrathin foil with a thickness ≤0.05mm. After homogenization smelting and carbide control, the finished cast billet possesses high purity, high uniformity, and a dispersed fine carbide structure, thereby ensuring excellent rolling plasticity. Limiting the thickness tolerance of the ultrathin foil to ±0.003mm ensures a high degree of consistency in the thickness of the ultrathin foil, thereby meeting the precision fitting requirements of high-end sealing components. The ultrathin foil material was defined as having excellent plate shape, no rolling breaks, and no microcracks. The excellent plate shape and absence of rolling breaks and microcracks indicate that the homogenization of the microstructure and the control of carbides in the finished billet effectively eliminated stress concentration points and defect inheritance. This proves that the homogenization smelting and carbide control method based on steady-state melting rate control has successfully achieved mass production adaptability of ultrathin high-temperature alloy ingots.

[0069] In summary, the specific performance indicators of this ultrathin foil, by verifying the rolling quality and surface integrity of the final product, ultimately validate the effectiveness of the solution to the technical problem of homogenized smelting and carbide control of high-temperature alloy ingots based on steady-state melting rate control at the end-product level.

[0070] The thickness of ultra-thin foil includes, but is not limited to, 0.03mm, 0.04mm, and 0.05mm.

[0071] In a second aspect, embodiments of this application provide an ultrathin foil material, which is prepared by the method described in any one of the first aspects; The ultra-thin high-temperature alloy ingot has an average carbide size ≤2μm, an alloy element segregation degree ≤±0.5%, an oxygen content ≤10ppm, and a nitrogen content ≤5ppm, with the carbides exhibiting a dispersed distribution. The ultra-thin high-temperature alloy ingot is defined as being prepared using the aforementioned high-temperature alloy ingot homogenization smelting method. This preparation method, based on steady-state melting rate control, performs homogenization smelting and carbide control, blocking microstructure inheritance at the source and achieving carbide dispersion and refinement, thereby providing a highly homogeneous, highly pure microstructure with finely dispersed carbides for the ultra-thin high-temperature alloy ingot. The ultra-thin high-temperature alloy ingot is defined as having an average carbide size ≤2μm. An average carbide size ≤2μm ensures that the carbide particles in the ultra-thin high-temperature alloy ingot are sufficiently fine, thereby eliminating stress concentration risks and ensuring high-temperature service stability. The ultra-thin high-temperature alloy ingot is limited to an alloy element segregation degree of ≤±0.5%. This ensures high compositional uniformity, guaranteeing microstructural stability and sealing tightness during high-temperature service. The oxygen content is limited to ≤10ppm. This ensures no external oxygen contamination, preventing oxide inclusions from detaching and causing uncontrolled sealing gaps during high-temperature service. The nitrogen content is limited to ≤5ppm. This ensures no external nitrogen contamination, preventing nitride inclusions from deteriorating high-temperature plasticity and sealing performance. Finally, the carbides are dispersed in the ultra-thin high-temperature alloy ingot. This dispersed distribution prevents localized carbide aggregation and continuous grain boundary segregation, avoiding carbide detachment and intergranular corrosion during high-temperature service.

[0072] In summary, by inheriting all the technical effects of the method described in the first aspect, this ultrathin high-temperature alloy ingot ultimately solves the technical problem of how to achieve homogenized smelting and carbide control of high-temperature alloy ingots based on steady-state control of melting rate, and realizes the high-temperature sealing reliability and airtightness of the ultrathin high-temperature alloy ingot.

[0073] The average carbide size of the ultrathin superalloy ingot includes, but is not limited to, 1.2 μm, 1.5 μm, 1.8 μm, and 2.0 μm. The segregation of alloying elements in the ultrathin superalloy ingot includes, but is not limited to, ±0.2%, ±0.3%, ±0.4%, and ±0.5%. The oxygen content of the ultrathin superalloy ingot includes, but is not limited to, 8 ppm, 9 ppm, and 10 ppm. The nitrogen content of the ultrathin superalloy ingot includes, but is not limited to, 3 ppm, 4 ppm, and 5 ppm.

[0074] The present application is further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to industry standards. If there is no corresponding industry standard, then generally accepted international standards, conventional conditions, or conditions recommended by the manufacturer are followed.

[0075] I. Implementation Examples

[0076] Example 1 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.10 wt%. The raw materials also include a carbon source with a content of 0.085 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0077] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0078] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0079] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1170℃ at a heating rate of 9℃ / min and held for 18h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0080] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0081] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0082] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.3%; the average size of carbides in the annealed ingot is 1.5 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 8 ppm, and the nitrogen content is 3 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.001 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.5%; the sealing life of the ultrathin foil is 1200 h; the high-temperature sealing leakage rate of the ultrathin foil is 1.5 × 10⁻⁶. -9 Pa·m 3 / s.

[0083] Example 2 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.08 wt%. The raw materials also include a carbon source with a content of 0.08 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0084] The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting was 4 Pa. The vacuum induction melting included a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period was 1465℃, and the holding time was 35 min; the temperature of the high-temperature refining period was 1525℃, and the holding time was 22 min.

[0085] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8000A, the voltage is 37V, the melting rate is 2.0 kg / min, the melting rate fluctuation is 0.18 kg / min, and the slag pool temperature is 1575℃.

[0086] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1160℃ at a heating rate of 9℃ / min and held for 20h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0087] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0088] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0089] Performance data: The alloy element segregation degree in the annealed ingot is 0.4%; the average size of carbides in the annealed ingot is 1.8 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 9 ppm, and the nitrogen content is 4 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.003 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.8%; the sealing life of the ultrathin foil is 1150 h; the high-temperature sealing leakage rate of the ultrathin foil is 2.0 × 10⁻⁶. -9 Pa·m 3 / s.

[0090] Example 3 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.12 wt%. The raw materials also include a carbon source with a content of 0.09 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0091] The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain a vacuum induction melted ingot. The vacuum degree of the vacuum induction melting was 2 Pa. The vacuum induction melting included a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period was 1465℃, and the holding time was 35 min. The temperature of the high-temperature refining period was 1525℃, and the holding time was 22 min.

[0092] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8500A, the voltage is 37V, the melting rate is 2.2 kg / min, the melting rate fluctuation is 0.12 kg / min, and the slag pool temperature is 1575℃.

[0093] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1180℃ at a heating rate of 9℃ / min and held for 15h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0094] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0095] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0096] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.2%; the average size of carbides in the annealed ingot is 1.2 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 6 ppm, and the nitrogen content is 2 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.003 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.2%; the sealing life of the ultrathin foil is 1380 h; the high-temperature sealing leakage rate of the ultrathin foil is 1.2 × 10⁻⁶. -9 Pa·m 3 / s.

[0097] Example 4 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.10%. The raw materials also include a carbon source with a content of 0.085%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0098] The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting was 4 Pa. The vacuum induction melting included a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period was 1465℃, and the holding time was 35 min; the temperature of the high-temperature refining period was 1525℃, and the holding time was 22 min.

[0099] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0100] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2Under the condition of Pa, the temperature was increased to 1170℃ at a heating rate of 9℃ / min and held for 18h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0101] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0102] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0103] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.35%; the average size of carbides in the annealed ingot is 1.6 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 7 ppm, and the nitrogen content is 3 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.002 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.4%; the sealing life of the ultrathin foil is 1250 h; the high-temperature sealing leakage rate of the ultrathin foil is 1.6 × 10⁻⁶. -9 Pa·m 3 / s.

[0104] Example 5 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.08 wt%. The raw materials also include a carbon source with a content of 0.08%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0105] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0106] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8000A, the voltage is 37V, the melting rate is 2.0 kg / min, the melting rate fluctuation is 0.18 kg / min, and the slag pool temperature is 1575℃.

[0107] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1160℃ at a heating rate of 9℃ / min and held for 20h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0108] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0109] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0110] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.45%; the average size of carbides in the annealed ingot is 1.9 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 9 ppm, and the nitrogen content is 4 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.003 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.9%; the sealing life of the ultrathin foil is 1100 h; the high-temperature sealing leakage rate of the ultrathin foil is 2.2 × 10⁻⁶. -9 Pa·m 3 / s.

[0111] Example 6 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.12 wt%. The raw materials also include a carbon source with a content of 0.09 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0112] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0113] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8500A, the voltage is 37V, the melting rate is 2.2 kg / min, the melting rate fluctuation is 0.12 kg / min, and the slag pool temperature is 1575℃.

[0114] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1180℃ at a heating rate of 9℃ / min and held for 15h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0115] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0116] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0117] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.25%; the average size of carbides in the annealed ingot is 1.3 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 5 ppm, and the nitrogen content is 2 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.002 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.1%; the sealing life of the ultrathin foil is 1400 h; the high-temperature sealing leakage rate of the ultrathin foil is 1.1 × 10⁻⁶. -9 Pa·m 3 / s.

[0118] Example 7 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.08 wt%. The raw materials also include a carbon source with a content of 0.075 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0119] The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting was 4 Pa. The vacuum induction melting included a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period was 1465℃, and the holding time was 35 min; the temperature of the high-temperature refining period was 1525℃, and the holding time was 22 min.

[0120] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8000A, the voltage is 37V, the melting rate is 2.0 kg / min, the melting rate fluctuation is 0.18 kg / min, and the slag pool temperature is 1575℃.

[0121] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2Under the condition of Pa, the temperature was increased to 1160℃ at a heating rate of 9℃ / min and held for 25h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0122] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0123] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0124] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.48%; the average size of carbides in the annealed ingot is 1.9 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 9 ppm, and the nitrogen content is 4 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.003 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.8%; the sealing life of the ultrathin foil is 1120 h; the high-temperature sealing leakage rate of the ultrathin foil is 2.1 × 10⁻⁶. -9 Pa·m 3 / s.

[0125] Example 8 The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.12 wt%. The raw materials also include a carbon source with a content of 0.095 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0126] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0127] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8500A, the voltage is 37V, the melting rate is 2.5 kg / min, the melting rate fluctuation is 0.10 kg / min, and the slag pool temperature is 1575℃.

[0128] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1200℃ at a heating rate of 9℃ / min and held for 15h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0129] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0130] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0131] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.28%; the average size of carbides in the annealed ingot is 1.4 μm, and the carbides are dispersed; the oxygen content in the high-temperature alloy ingot is 6 ppm, and the nitrogen content is 3 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.002 mm, and the plate shape is excellent, with no rolling breaks or microcracks; the ultrathin foil shows no intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 1.3%; the sealing life of the ultrathin foil is 1350 h; the high-temperature sealing leakage rate of the ultrathin foil is 1.4 × 10⁻⁶. -9 Pa·m 3 / s.

[0132] II. Comparative Example Comparative Example 1 (Single vacuum induction melting, without electroslag remelting process) The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, and manganese is 0.5%. No titanium carbide stabilizer is added to the raw materials. No carbon source is added to the raw materials. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0133] The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. A common refractory crucible was used for the vacuum induction melting. The vacuum degree of the vacuum induction melting was 3 Pa. The vacuum induction melting included a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period was 1465℃, and the holding time was 35 min; the temperature of the high-temperature refining period was 1525℃, and the holding time was 22 min.

[0134] The electroslag remelting process is omitted.

[0135] The vacuum induction melting ingot was subjected to conventional annealing to obtain an annealed ingot. The conventional annealing process consisted of holding at 1150℃ for 10 hours, followed by natural air cooling to room temperature.

[0136] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0137] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0138] Performance data: The segregation degree of alloying elements in the annealed ingot is 1.2%; the average size of carbides in the annealed ingot is 6.5 μm, and the carbides exhibit localized aggregation; the oxygen content in the high-temperature alloy ingot is 25 ppm, and the nitrogen content is 18 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.008 mm, and the plate shape is not excellent, with rolling breaks and microcracks; the ultrathin foil exhibits intergranular corrosion when used at 900℃; the high-temperature creep deformation of the ultrathin foil is 5.5%; the sealing life of the ultrathin foil is 300 h; the high-temperature sealing leakage rate of the ultrathin foil is 8.5 × 10⁻⁶. -8 Pa·m 3 / s.

[0139] Comparative Example 2 (vacuum homogenization annealing treatment) The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.10%. The raw materials also include a carbon source with a content of 0.078 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0140] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0141] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0142] The electroslag remelted ingot is directly subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0143] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0144] Performance data: The segregation degree of alloying elements in the electroslag remelting ingot is 0.8%; the average size of carbides in the electroslag remelting ingot is 4.5 μm, and the carbides are in a residual blocky state; the oxygen content in the high-temperature alloy ingot is 18 ppm, and the nitrogen content is 12 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.006 mm, and the plate shape is not excellent, with rolling breaks and microcracks; the ultrathin foil exhibits intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 4.2%; the sealing life of the ultrathin foil is 450 h; carbides detach from the ultrathin foil during high-temperature service; the high-temperature sealing airtightness leakage rate of the ultrathin foil is 5.2 × 10⁻⁶. -8 Pa·m 3 / s.

[0145] Comparative Example 3 (no carbide stabilizer titanium added to the raw materials) The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, and manganese is 0.5%. No titanium carbide stabilizer is added to the raw materials. The raw materials also include a carbon source with a content of 0.078 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0146] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0147] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0148] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2Under the condition of Pa, the temperature was increased to 1170℃ at a heating rate of 9℃ / min and held for 18h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0149] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0150] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0151] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.9%; the average size of carbides in the annealed ingot is 5.2 μm, and the carbides are in a non-dispersed distribution state; the oxygen content in the high-temperature alloy ingot is 20 ppm, and the nitrogen content is 14 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.007 mm, and the plate shape is not excellent, with rolling breaks and microcracks; the ultrathin foil exhibits intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 5.0%; the sealing life of the ultrathin foil is 350 h; carbides detach from the ultrathin foil during high-temperature service; the high-temperature sealing airtightness leakage rate of the ultrathin foil is 7.5 × 10⁻⁶. -8 Pa·m 3 / s.

[0152] Comparative Example 4 (Titanium addition exceeds the scope of the embodiments in this application) The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.20 wt%. The raw materials also include a carbon source with a content of 0.078 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0153] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0154] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0155] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1170℃ at a heating rate of 9℃ / min and held for 18h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0156] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0157] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0158] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.82%; the average size of carbides in the annealed ingot is 4.6 μm, and the carbides are in a non-dispersed distribution state; the oxygen content in the high-temperature alloy ingot is 21 ppm, and the nitrogen content is 14 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.006 mm, and the plate shape is not excellent, with rolling breaks and microcracks; the ultrathin foil exhibits intergranular corrosion during service at 900℃; the high-temperature creep deformation of the ultrathin foil is 4.6%; the sealing life of the ultrathin foil is 400 h; carbides detach from the ultrathin foil during high-temperature service; the high-temperature sealing airtightness leakage rate of the ultrathin foil is 6.5 × 10⁻⁶. -8 Pa·m 3 / s.

[0159] Comparative Example 5 (vacuum homogenization annealing temperature is lower than the range of embodiments in this application) The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.10 wt%. The raw materials also include a carbon source with a content of 0.078 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0160] The pretreated raw materials are subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melted ingots. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0161] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0162] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2 Under the condition of Pa, the temperature was increased to 1050℃ at a heating rate of 9℃ / min and held for 18h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the temperature was cooled to room temperature with the furnace.

[0163] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0164] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0165] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.88%; the average size of carbides in the annealed ingot is 4.5 μm, and the carbides are in a non-dispersed distribution state; the oxygen content in the high-temperature alloy ingot is 17 ppm, and the nitrogen content is 11 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.006 mm, and the plate shape is not excellent, with rolling breaks and microcracks; the ultrathin foil exhibits intergranular corrosion when serving at 900℃; the high-temperature creep deformation of the ultrathin foil is 4.3%; the sealing life of the ultrathin foil is 430 h; carbides detach from the ultrathin foil during high-temperature service; the high-temperature sealing airtightness leakage rate of the ultrathin foil is 5.5 × 10⁻⁶. -8 Pa·m 3 / s.

[0166] Comparative Example 6 (vacuum induction melting was not carried out under an argon protective atmosphere) The raw materials are pretreated to obtain pretreated raw materials. The raw materials are high-purity raw materials with a purity of 99.95 wt%, and include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium carbide stabilizer. By mass fraction, the added amounts of chromium are 22.0%, iron is 18.00%, cobalt is 1.00%, molybdenum is 9.0%, tungsten is 0.5%, manganese is 0.5%, and titanium is 0.10 wt%. The raw materials also include a carbon source with a content of 0.078 wt%. The pretreatment includes removing oxide scale and oil from the surface of the raw materials and vacuum drying the raw materials.

[0167] The pretreated raw materials are induction melted under vacuum conditions to obtain vacuum induction melted ingots. The vacuum induction melting is not performed under an argon protective atmosphere. The vacuum degree of the vacuum induction melting is 3 Pa. The vacuum induction melting includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1465℃, and the holding time is 35 min; the temperature of the high-temperature refining period is 1525℃, and the holding time is 22 min.

[0168] The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelting uses a calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina, and magnesium oxide is 6:3:1. The electroslag remelting current is 8200A, the voltage is 37V, the melting rate is 2.1 kg / min, the melting rate fluctuation is 0.15 kg / min, and the slag pool temperature is 1575℃.

[0169] The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenization annealing includes: annealing at a vacuum degree of 1×10⁻⁻⁻⁶. 2Under the condition of Pa, the temperature was increased to 1170℃ at a heating rate of 9℃ / min and held for 18h. Then, the temperature was decreased to 920℃ at a cooling rate of 6.5℃ / min, and then decreased to 620℃ at a cooling rate of 3℃ / min. Finally, the furnace was cooled to room temperature.

[0170] The annealed ingot is subjected to double-sided machining to obtain a high-temperature alloy ingot. The single-sided cutting removal amount during the double-sided machining is 0.25 mm, and the surface roughness Ra of the high-temperature alloy ingot is 1.0 μm.

[0171] The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled, and solution-treated to obtain an ultra-thin foil with a thickness of 0.03 mm.

[0172] Performance data: The segregation degree of alloying elements in the annealed ingot is 0.78%; the average size of carbides in the annealed ingot is 4.0 μm, and the carbides are in a non-dispersed distribution state; the oxygen content in the high-temperature alloy ingot is 28 ppm, and the nitrogen content is 20 ppm; the thickness of the ultrathin foil is 0.03 mm, the thickness tolerance is 0.006 mm, and the plate shape is not excellent, with rolling breaks and microcracks; the ultrathin foil exhibits intergranular corrosion when in service at 900℃; the high-temperature creep deformation of the ultrathin foil is 4.3%; the sealing life of the ultrathin foil is 430 h; carbides detach from the ultrathin foil during high-temperature service; the high-temperature sealing leakage rate of the ultrathin foil is 5.5 × 10⁻⁶. -8 Pa·m 3 / s.

[0173] Experimental methods for evaluating results: 1. Method for detecting the segregation degree of alloying elements Sampling was taken at three locations: the core, half radius, and edge of the annealed ingot or the electroslag remelted ingot, with at least three sampling points at each location. The percentage content of chromium, iron, cobalt, molybdenum, tungsten, manganese, and titanium at each sampling point was determined using a direct-reading spectrometer or inductively coupled plasma atomic emission spectrometer. The arithmetic mean of the measured values ​​for each element at all sampling points was taken as the nominal composition of that element. The maximum absolute deviation between the measured values ​​at each sampling point and the nominal composition was taken as the maximum segregation amount of that element. The ratio of the maximum segregation amount to the nominal composition was taken as the degree of segregation of that element. The degree of segregation of the alloying element composition was the maximum value among all element segregation degrees.

[0174] 2. Method for detecting the average size of carbides Samples were taken from the core of the annealed ingot or the electroslag remelted ingot, and metallographic specimens were prepared by mechanical grinding and polishing. The morphology of the carbides was observed using a scanning electron microscope in backscattered electron mode at a magnification of not less than 5000x. At least 20 carbide particles were randomly selected within the field of view, and the equivalent circle diameter of each carbide particle was measured using image analysis software. The arithmetic mean of the equivalent circle diameters of all carbide particles was taken as the average size of the carbide.

[0175] 3. Methods for detecting carbide distribution state Samples were taken from the core of the annealed ingot or the electroslag remelted ingot, and metallographic specimens were prepared by mechanical grinding and polishing. The distribution of carbides was observed using a scanning electron microscope in backscattered electron mode at a magnification of at least 1000x. Five equally spaced straight lines were drawn along both the horizontal and vertical directions within the field of view, and the frequency distribution of intersections between the lines and the carbides was statistically analyzed. If there were no obvious aggregation areas of carbides within the field of view and the frequency distribution of intersections along the lines was uniform, the carbides were determined to be in a diffuse distribution state. If there were obvious aggregation areas of carbides within the field of view or the frequency of intersections along a certain line was significantly higher than that along other lines, the carbides were determined to be in a locally aggregated state or a residual blocky state.

[0176] 4. Oxygen content detection methods Samples were taken from the core of the high-temperature alloy ingot, and the oxygen content was determined using either the inert gas melting-infrared absorption method or the inert gas melting-thermal conductivity method. The sample was placed in a graphite crucible and melted at high temperature under inert gas protection. The released oxygen reacted with carbon to form carbon monoxide, which was then quantitatively determined using an infrared detector or a thermal conductivity detector. The oxygen content in the high-temperature alloy ingot was the arithmetic mean of three parallel measurements.

[0177] 5. Nitrogen content detection methods A sample was taken from the core of the high-temperature alloy ingot, and the nitrogen content was determined using the inert gas melting-thermal conductivity method. The sample was placed in a graphite crucible and melted at high temperature under inert gas protection. The released nitrogen was quantitatively measured using a thermal conductivity detector. The nitrogen content in the high-temperature alloy ingot was the arithmetic mean of three parallel measurements.

[0178] 6. Methods for testing the thickness of ultra-thin foil materials At least five measurement points are equally spaced along the width of the ultrathin foil, and at least five measurement points are equally spaced along the length of the ultrathin foil, forming at least 25 measurement grids. The thickness value of each grid point is measured using a micrometer or a laser thickness gauge. The arithmetic mean of the thickness values ​​of all measurement points is taken as the thickness of the ultrathin foil, and half of the difference between the maximum and minimum thickness values ​​of all measurement points is taken as the thickness tolerance.

[0179] 7. Rolled Strip Breakage Detection Method The ultrathin foil was prepared by forging, hot rolling, precision cold rolling, and solution treatment of the high-temperature alloy ingot. The number of strip breaks and the total number of rolling passes were recorded during the rolling process. The strip breakage rate is the ratio of the number of strip breaks to the total number of rolling passes, expressed as a percentage.

[0180] 8. Microcrack Detection Methods At least 10 fields of view are randomly selected on the surface of the ultrathin foil, each with an area of ​​not less than 1 cm². The surface morphology of each field of view is observed using an optical microscope or a scanning electron microscope at a magnification of not less than 200x. The number and length of microcracks in each field of view are counted, and the ratio of the total length of microcracks in all fields of view to the total area of ​​all fields of view is taken as the microcrack density. If no cracks longer than 50 μm are observed in any field of view, it is determined that there are no microcracks.

[0181] 9. Plate shape detection method The ultrathin foil is placed flat on a horizontal testing platform, and the maximum gap between the ultrathin foil and the platform is measured using a feeler gauge or laser profilometer. If the maximum gap does not exceed 5% of the thickness of the ultrathin foil, the foil shape is considered excellent. Simultaneously, the surface roughness Ra value of the ultrathin foil is measured using a surface roughness meter.

[0182] 10. Detection method for intergranular corrosion during service at 900℃ The ultrathin foil was processed into standard intergranular corrosion samples, and then subjected to intergranular corrosion testing after being held at 900℃ for 100 hours. The intergranular corrosion test was conducted according to GB / T 7998-2005 "Method for Determination of Intergranular Corrosion of Aluminum Alloys" or equivalent standards, and the grain boundary morphology of the corroded samples was observed using a metallographic microscope. If there were no obvious corrosion grooves or widening of the grain boundaries, it was determined that there was no intergranular corrosion.

[0183] 11. High-Temperature Creep Deformation Detection Method The ultrathin foil material is processed into standard creep specimens and subjected to creep tests at 900℃ and a stress of 50MPa for at least 100 hours. The total deformation of the specimen during the test time is measured using an extensometer, and the ratio of the total deformation to the original gauge length of the specimen is taken as the high-temperature creep deformation. If the high-temperature creep deformation does not exceed 2%, it is considered to be small.

[0184] 12. Sealing life testing method The ultrathin foil was processed into standard sealing samples, and a high-temperature sealing airtightness test was conducted under simulated service conditions. The time interval from the initial state of the ultrathin foil to the point where the high-temperature sealing airtightness failed to meet the standard was recorded as the sealing life. Based on the sealing life of Example 1, the improvement ratio of the sealing life of other examples relative to Example 1 was calculated.

[0185] 13. High-Temperature Sealing Tightness Testing Method The ultrathin foil material was processed into standard sealing samples, and airtightness tests were conducted under simulated service temperature and pressure. The leakage rate of the ultrathin foil material was measured using a helium mass spectrometer or the pressure drop method. If the leakage rate did not exceed the design allowable value, the high-temperature sealing airtightness was deemed to meet the standard or design requirements; if the leakage rate exceeded the design allowable value, the high-temperature sealing was deemed to have failed due to leakage or the sealing gap was deemed to have exceeded the standard.

[0186] 14. Surface Defect Detection Methods At least 10 fields of view are randomly selected on the surface of the ultrathin foil, each with an area of ​​not less than 1 cm². The surface morphology of each field of view is observed using an optical microscope or a scanning electron microscope at a magnification of not less than 100x. The number and size of pits and scratches in each field of view are counted, and the ratio of the total area of ​​pits and scratches in all fields of view to the total area of ​​all fields of view is taken as the surface defect rate.

[0187] 15. Detection method for carbide shedding during high-temperature service The ultrathin foil was processed into standard samples and kept at 900℃ for 200 hours before surface morphology observation. The sample surface was observed using a scanning electron microscope at a magnification of no less than 1000x. If pits or holes formed by carbide detachment were present on the sample surface, it was determined that carbide detachment had occurred during high-temperature service.

[0188] Table 1. Effect Data of Example Implementation Table 2 Comparative Effect Data Table As shown by the examples and comparative effect data, the technical advancements of this application's technical solution include: The segregation degree of the composition is reduced by more than 75%: the segregation degree of the example is 0.2%~0.48%, the segregation degree of the comparative example is 0.78%~1.2%, and the segregation degree is controlled within 0.5% by electroslag remelting duplex smelting.

[0189] Carbide size reduction of more than 60%: The average carbide size in the example is 1.2μm~1.9μm, and in the comparative example it is 4.0μm~6.5μm. The carbon source and titanium synergistic stabilization control the carbide size to within 2μm.

[0190] Oxygen and nitrogen impurities are reduced by more than 70%: in the example, the oxygen content is 5ppm~9ppm and the nitrogen content is 2ppm~4ppm; in the comparative example, the oxygen content is 17ppm~28ppm and the nitrogen content is 11ppm~20ppm. Argon protection and high-purity raw materials control the impurity content to within 10ppm and 5ppm, respectively.

[0191] The sealing life is increased by more than 3 times: the sealing life of the example is 1100h~1400h, and that of the comparative example is 300h~480h. Vacuum homogenization annealing significantly extends the sealing life.

[0192] The airtightness leakage rate was reduced by two orders of magnitude: the leakage rate in the example was 1.1 × 10⁻⁶. -9 ~2.2×10 -9 Pa·m 3 / s, comparative example 5.2×10 -8 ~8.5×10 -8 Pa·m 3 / s, significantly improving the high-temperature sealing performance of ultra-thin foil materials.

[0193] Rolling breakage rate reduced to 0: The example showed no rolling breakage and no microcracks, while the comparative example showed a breakage rate of 17%~35%. Process synergistic optimization enabled stable mass production of ultra-thin foil materials.

[0194] Detailed explanation of the attached diagram: Figure 1 This is a metallographic image of the high-temperature alloy ingot in Example 1 of this application; Figure 2 This is a metallographic image of the high-temperature alloy ingot in Comparative Example 1 of this application. It can be clearly seen from the image that the carbides in the high-temperature alloy ingot of Example 1 are dispersed and small in size, while the carbides in the high-temperature alloy ingot of Comparative Example 1 are large in size and locally aggregated.

[0195] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for homogenizing high-temperature alloy ingots, characterized in that, The method includes: The raw materials are pretreated to obtain pretreated raw materials; the raw materials include nickel, chromium, iron, cobalt, molybdenum, tungsten, manganese, and carbide stabilizer titanium, wherein the amount of chromium added is 21.0~23.0 wt%, the amount of iron added is 17.00~19.00 wt%, the amount of cobalt added is 0.50~1.50 wt%, the amount of molybdenum added is 8.0~10.0 wt%, the amount of tungsten added is 0.2~0.8 wt%, the amount of manganese added is 0.2~0.8 wt%, the amount of titanium added is 0.08~0.12 wt%, and the balance is nickel; The pretreated raw materials were subjected to vacuum induction melting under an argon protective atmosphere to obtain vacuum induction melting ingots. The vacuum induction melting ingot is subjected to electroslag remelting to obtain an electroslag remelted ingot. The electroslag remelted ingot is subjected to vacuum homogenization annealing to obtain an annealed ingot. The vacuum homogenizing annealing treatment comprises: under the condition of vacuum degree ≤10 -2 Pa, heating to 1160℃~1200℃ at the heating rate of 8℃ / min~10℃ / min, and keeping for 15h~25h, then cooling to 890℃~950℃ at the cooling rate of 6℃ / min~7℃ / min, and cooling to 590℃~650℃ at the cooling rate of 2℃ / min~4℃ / min, and then furnace cooling to room temperature; The annealed ingot is then subjected to double-sided machining and finishing to obtain a high-temperature alloy ingot. The single-sided cutting removal amount of the double-sided machining finishing is 0.20mm~0.30mm, and the surface roughness Ra of the high-temperature alloy ingot is ≤1.2μm.

2. The method according to claim 1, characterized in that, The raw material is a high-purity raw material with a purity of ≥99.95wt%; the pretreatment includes removing the oxide scale and oil stains on the surface of the raw material and vacuum drying the raw material.

3. The method according to claim 1, characterized in that, The vacuum degree of the vacuum induction melting is ≤5Pa; The vacuum induction melting process includes a low-temperature melting period and a high-temperature refining period. The temperature of the low-temperature melting period is 1450℃~1480℃, and the holding time is 30min~40min. The temperature of the high-temperature refining period is 1500℃~1550℃, and the holding time is 20min~25min.

4. The method according to claim 1, characterized in that, The electroslag remelting uses calcium fluoride-alumina-magnesium oxide refining slag, wherein the mass ratio of calcium fluoride, alumina and magnesium oxide is 6:3:1; The current for electroslag remelting is 8000A~8500A, the voltage is 35V~40V, the melting rate is 2.0kg / min~2.5kg / min, the melting rate fluctuation is ≤±0.2kg / min, and the slag pool temperature is 1550℃~1600℃.

5. The method according to claim 1, characterized in that, In the annealed ingot after vacuum homogenization annealing, the average size of the carbides is ≤2μm, and the carbides are in a dispersed distribution state. The alloy element composition segregation degree in the annealed ingot after vacuum homogenization annealing is ≤ ±0.5%.

6. The method according to claim 1, characterized in that, The oxygen content in the high-temperature alloy ingot is ≤10ppm and the nitrogen content is ≤5ppm.

7. The method according to claim 1, characterized in that, The raw materials also include a carbon source, the content of which is 0.075wt%~0.095wt%.

8. The method according to claim 7, characterized in that, The carbon source is 0.085 wt% carbon, and the titanium content is 0.10 wt%; the vacuum degree of the vacuum induction melting is 0.5 Pa; the current of the electroslag remelting is 8200 A, the melting rate is 2.1 kg / min, and the melting rate fluctuation is ±0.15 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1170℃, and the holding time is 18 h; or, The carbon source is 0.08 wt% carbon, and the titanium addition is 0.08 wt%; the vacuum degree of the vacuum induction melting is 0.8 Pa; the current of the electroslag remelting is 8000 A, the melting rate is 2.0 kg / min, and the melting rate fluctuation is ±0.18 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1160℃, and the holding time is 20 h; or, The carbon source is 0.09 wt% carbon, and the titanium content is 0.12 wt%; the vacuum degree of the vacuum induction melting is 0.2 Pa; the current of the electroslag remelting is 8500 A, the melting rate is 2.2 kg / min, and the melting rate fluctuation is ±0.12 kg / min; the holding temperature of the vacuum homogenization annealing treatment is 1180℃, and the holding time is 15 h.

9. The method according to claim 1, characterized in that, The high-temperature alloy ingot is forged, hot-rolled, precision cold-rolled and solution-treated to obtain an ultra-thin foil with a thickness of ≤0.05mm. The thickness tolerance of the ultra-thin foil is ±0.003mm, and it has excellent plate shape and no rolling breaks or microcracks.

10. An ultrathin foil material, characterized in that, The ultrathin foil is made from a high-temperature alloy ingot, which is prepared by the method described in any one of claims 1 to 9; The ultrathin foil has an average carbide size of ≤2μm, an alloy element segregation degree of ≤±0.5%, an oxygen content of ≤10ppm, a nitrogen content of ≤5ppm, and the carbides are in a dispersed distribution state.

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