Wide cold-rolled sheet containing cobalt-nickel-based superalloy GH4098 and manufacturing method of wide cold-rolled sheet

Abstract

The invention provides a cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet and a manufacturing method thereof. The GH4098 cold-rolled sheet comprises, by mass, 17.50%-19.50% of Cr, 5%-8% of Co, 5.5%-7.0% of W, 3.5%-5.0% of Mo, 2.50%-3.0% of Al, 1.0%-1.5% of Ti, smaller than or equal to 3.00% of Fe, smaller than or equal to 1.50% of Nb, smaller than or equal to 0.30% of Mn, smaller than or equal to 0.30% of Si, smaller than or equal to 0.10% of C, smaller than or equal to 0.015% of S and smaller than or equal to 0.015% of P. The manufacturing method comprises the steps that S1, a plate blank is forged, the forging frequency and temperature are controlled in a light hammer and fast beating mode, and a uniform forged blank is prepared; s2, hot-rolling cogging: heating through a sheath and closing cooling water for rolling to obtain a hot-rolled semi-finished product; and S3, cold rolling machining is conducted, specifically, the wide cold-rolled sheet is manufactured through the repeated cold rolling and intermediate solution heat treatment alternating technology. Through component optimization and process improvement, the strength, plasticity and grain size uniformity of the material are remarkably improved, the manufactured wide cold-rolled sheet is smooth in surface and high in glossiness and can meet the performance requirements in the fields of aerospace and high-end manufacturing, and meanwhile the problems of edge cracking and non-uniform performance in wide plate production in the prior art are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of metal material manufacturing, and in particular to a cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet and a manufacturing method thereof. Background Art

[0002] GH4098 alloy is a cobalt-containing nickel-based high-temperature alloy recently developed in my country. It is a typical difficult-to-process alloy in the field of high-temperature materials. Due to its excellent high-temperature strength, oxidation resistance and good weldability, it is widely used in baffles, heat shields, reinforcements and other high-temperature working parts of aerospace engines. The main characteristics of this alloy are that it achieves solid solution strengthening through W, Cr, Mo, and Co elements, and precipitation strengthening by using the γ' phase generated by Al and Ti. At the same time, the addition of Nb further improves the stability of the γ' phase. However, despite the excellent mechanical properties and high-temperature properties of this alloy, there are still many technical difficulties in its processing and manufacturing process.

[0003] First of all, GH4098 alloy is a typical solid solution strengthened and precipitation strengthened high temperature alloy that is difficult to deform. The alloy contains a high proportion of strengthening elements (such as W, Mo, Co, Al and Ti), and the total content of these elements reaches more than 15%, which leads to a very obvious solid solution strengthening effect of the material at high temperature, and a large amount of carbides (such as M23C6, WC, Mo2C) and γ' phase are generated at the same time. Although these strengthening phases significantly improve the high temperature performance of the alloy, they also greatly reduce the processing plasticity of the material, making hot processing processes such as forging and rolling extremely difficult, and it is very easy to have edge cracking and cracking problems during processing, especially when producing wide plates.

[0004] Secondly, GH4098 alloy is prone to coarse grain structure and grain boundary oxidation during hot working. This phenomenon significantly limits the alloy's processing temperature range, making it difficult to select appropriate processing parameters during forging and rolling. In addition, since grain coarsening will further weaken the plasticity of the material, especially in the subsequent cold rolling process, it is more likely to cause cracks, thereby reducing the material's yield and utilization rate.

[0005] For the production of wide-width plates, the material width under conventional processes is usually difficult to exceed 800mm, while the demand for wide-width plates in the aerospace field is growing, requiring the plate width to reach more than 1000mm. However, when producing wide-width plates, the existing processing technology often has problems such as cracked edges, cracks and uneven deformation, resulting in low pass rates or even failure to produce wide-width plates that meet the requirements.

[0006] In addition, the room temperature performance requirements of GH4098 cold-rolled thin plates are relatively high, such as tensile strength requirements of ≤1180MPa, elongation requirements of ≥25%, and grain size requirements of 5-8 levels with a grade difference of no more than 2 levels. It is difficult to simultaneously meet the above performance indicators and manufacturing process requirements in the existing technology, especially in controlling grain uniformity and finished product performance stability. There is still a large technical gap.

[0007] In summary, in order to address the problems of edge cracking, coarse grains and grain boundary oxidation in the processing of GH4098 alloy, as well as the insufficient manufacturing capacity of existing wide-width plates, it is urgent to develop an optimized manufacturing process to comprehensively improve processing plasticity and material utilization from forging to hot rolling to cold rolling, so as to meet the urgent demand for high-performance wide-width cold-rolled thin plates in the aerospace field. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a wide-width cold-rolled sheet of a cobalt-containing nickel-based high-temperature alloy GH4098, so as to solve the problems of limited width, uneven mechanical properties and poor surface quality of conventional cold-rolled sheets in the prior art.

[0009] In order to overcome the defects of the above-mentioned prior art, the present invention provides a cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled thin plate, comprising the following components by mass: Cr: 17.50-19.50%, Co: 5-8%, W: 5.5-7.0%, Mo: 3.5-5.0%, Al: 2.50-3.0%, Ti: 1.0-1.5%, Fe≤3.00%, Nb≤1.50%, Mn≤0.30%, Si≤0.30%, C≤0.10%, S≤0.015%, P≤0.015%, and the balance is Ni and other inevitable impurities.

[0010] Compared with the prior art, the wide cold-rolled thin plate of the cobalt-containing nickel-based high-temperature alloy GH4098 of the present application has the following advantages: the present invention realizes the synergistic effect of solid solution strengthening and aging strengthening by precisely controlling the content and proportion of strengthening elements such as Cr, Co, W, Mo, Al and Ti, so that the alloy maintains excellent strength and oxidation resistance at a high temperature of 1000°C, and has good plasticity and toughness, meeting the dual requirements of material strength and toughness in the field of aerospace, which specifically include: Improved stability of strengthening phase: Adding 5-8% Co and less than 1.5% Nb to the alloy effectively improves the stability of the γ' phase, inhibits the precipitation coarsening phenomenon at high temperatures, improves the stability of the grain boundary, reduces the risk of grain boundary embrittlement, and thus improves the high temperature strength and service life of the material; Enhanced crack resistance: By controlling the W and Mo contents to 5.5-7.0% and 3.5-5.0% respectively, and combining the synergistic effect of trace elements such as Ti and Al, the present invention significantly improves the processing plasticity of the alloy, reduces the probability of hot cracks and cold-rolled cracks during processing, and lays the foundation for the production of wide cold-rolled thin plates; Grain size uniformity: The precise ratio of Ti and Al in the alloy improves the alloy's recrystallization ability by controlling the precipitation amount of γ' phase, ensuring that the grain size of the thin plate reaches 5-8 levels with a grade difference of no more than 2, effectively improving the performance uniformity of the material; Improved high-temperature oxidation resistance: The Cr content (17.50-19.50%) is optimized in the alloy of the present invention. While enhancing the corrosion resistance, combined with the solid solution strengthening effect of W and Co, the alloy exhibits excellent oxidation resistance in a high-temperature oxidation environment.

[0011] Wide size realization: The present invention achieves stable production of cold-rolled thin plates with a width of 1000 mm or more by controlling composition and improving processing adaptability, providing an important domestic material alternative for high-end fields such as aerospace.

[0012] In summary, the present invention effectively overcomes the technical problems of insufficient strength, poor plasticity, easy cracking and difficulty in achieving wide width of cold-rolled thin plates in the prior art by optimizing the design of the GH4098 alloy composition, significantly improves the comprehensive performance of the alloy, and has broad market prospects and technical application value.

[0013] In a possible implementation, the thickness of the cold-rolled sheet is 0.5±0.05 mm, the width is greater than 1000 mm, and the performance parameters of the cold-rolled sheet at room temperature include: σb≤1180 MPa, δ5≥25%, and the grain size is 5-8 levels with a grade difference of no more than 2.

[0014] Compared with the prior art, the above technical scheme is adopted, which can ensure that the cold-rolled thin plate has high strength, high toughness, excellent dimensional accuracy and structural uniformity by optimizing the control of thickness, strength, elongation and grain size. By strictly controlling the thickness within the range of 0.5±0.1mm, as well as performance parameters such as σb, δ5 and grain size, the cold-rolled thin plate can not only meet the demand for lightweight thin plate materials in high-end fields such as aerospace, but also maintain stable strength and ductility under high temperature and complex stress environment. The grain size is set to 5-8 levels with a level difference of no more than 2. By suppressing the phenomenon of uneven structure and over-coarse grains, the plasticity and crack resistance of the material are further improved.

[0015] Another technical problem to be solved by the present invention is to provide a method for manufacturing a wide-width cold-rolled sheet of a cobalt-containing nickel-based high-temperature alloy GH4098, so as to solve the problems of easy edge cracking during forging, difficult hot rolling temperature control, improper control of cold rolling deformation and poor solution treatment effect existing in the conventional cold-rolled sheet manufacturing method in the prior art.

[0016] In order to overcome the above defects of the prior art, the present invention provides a method for manufacturing a wide cold-rolled sheet of a cobalt-containing nickel-based high-temperature alloy GH4098, comprising the following steps: S1: Forged slab A GH4098 alloy steel ingot is selected and forged to obtain a forged blank, wherein the chemical composition of the alloy steel ingot is the same as the chemical composition requirements of the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet; S2: Hot rolling The billet obtained in step S1 is heated and opened to obtain a GH4098 slab, which is then heated to a furnace temperature of 1200±10° C. by encapsulation, kept warm and the cooling water of the rolling mill is turned off, and then rolled to obtain a hot-rolled semi-finished product; S3: Cold rolling The hot-rolled semi-finished product obtained in step S2 is subjected to solution heat treatment, pickling, and grinding in sequence, and then enters cold rolling treatment. When the total deformation of the hot-rolled semi-finished product reaches 30%, it is subjected to solution heat treatment again to soften the hot-rolled semi-finished product. Subsequently, the alternating operation of cold rolling treatment and solution heat treatment is repeated until the cold rolling is achieved to the desired thickness. After pickling and finishing again, the cobalt-containing nickel-based high-temperature alloy GH4098 wide-width cold-rolled sheet is obtained by solution treatment of the finished product.

[0017] The present invention discloses a method for manufacturing a wide-width cold-rolled sheet of a cobalt-containing nickel-based high-temperature alloy GH4098, which has the following advantages over the prior art: the manufacturing method of the present invention rationally optimizes the hot working plasticity and cold rolling deformation capacity of the alloy through a scientific combination of forging, hot rolling and cold rolling processes, and realizes grain refinement and performance stabilization through multiple solid solution heat treatments, successfully solving the key problems in the prior art and laying a technical foundation for the large-scale production of high-performance cobalt-containing nickel-based high-temperature alloy wide-width cold-rolled sheets, and specifically includes the following principles: the manufacturing method of the present invention effectively reduces the edge cracking problem caused by the rapid temperature drop during the hot rolling process by means of jacket heating and shutting off the cooling water of the rolling mill, and at the same time improves the wide-width forming capacity of the sheet, and adopts By using alternating cold rolling and solution heat treatment processes, the uniformity of the grain size of the cold-rolled thin plate is significantly improved, and the fluctuations in the organization and performance of the plate during processing are effectively controlled; further, by accurately controlling the single-pass deformation and total deformation of cold rolling, combined with the regulation of grains and mechanical properties by solution treatment, the strength, toughness and dimensional accuracy of the thin plate are significantly improved; in the method of the present invention, the optimization of the solution treatment of the finished product ensures that the grain size of the cold-rolled thin plate is between levels 5 and 8 and the level difference does not exceed 2, and the final product has excellent strength, plasticity and high-temperature performance, and ultimately realizes the domestic production of plates with a width of 1000 mm and above, overcoming the problem of limited width and dependence on imports of plates in traditional processes, and has important technical and market value in the aerospace field.

[0018] In a possible implementation manner, in the step S1, the forging method is: heating the GH4098 alloy steel ingot and then forging it into a forging blank by two-fire forging, and the heating temperature is 1200±10°C.

[0019] Compared with the existing technology, the above technical scheme can significantly optimize the temperature control and plastic deformation behavior during the forging process, thereby achieving higher quality billet manufacturing: by controlling the heating temperature to 1200±10℃, it can ensure that the GH4098 alloy maintains suitable plasticity during the deformation process, while avoiding grain coarsening and oxidation defects caused by excessively high temperatures, as well as processing cracking problems caused by excessively low temperatures. In addition, the use of the 2-fire forging process can reduce local stress concentration through multiple re-melting and uniform deformation, further improving the organizational uniformity and quality stability of the forged billet.

[0020] In a possible implementation, in step S1, during the forging process, the hammering frequency is 30-45 times / min, and the final forging temperature is ≥1000°C.

[0021] Compared with the prior art, the above technical solution can optimize the control of heat loss and the distribution of deformation stress during the forging process, thereby effectively improving the quality and yield rate of GH4098 alloy forging billets: by setting the hammering frequency to 30-45 times / min, it is ensured that continuous deformation can be completed at a faster pace during the forging process to avoid the billet temperature from dropping too quickly, especially under the condition that high-temperature alloys are more likely to lose plasticity due to cooling, the good plasticity of the material can be maintained; at the same time, the setting of the final forging temperature ≥1000°C can effectively prevent the material from being forged at a low temperature, avoiding the occurrence of grain boundary cracking and work hardening.

[0022] In a possible implementation, in step S1, during the forging process, the frequency of hammering the edges of the steel ingot is 40-45 times / min, and the frequency of hammering the X / Y / Z surfaces of the steel ingot is 30-40 times / min, and when hammering the X surface, the deformation rate of each hammer is ≥6%, and when hammering the Y / Z / edge surface, the deformation rate of each hammer is ≥3%.

[0023] Compared with the prior art, the above technical solution can quickly trim the corners of the steel ingot by setting the frequency of hammering the corners to 40-45 times / min, reduce stress concentration caused by sharp corners, avoid the generation of cracks in the early stage of forging, and at the same time, ensure uniform temperature distribution in the corner area, and reduce the risk of material loss of plasticity caused by sudden temperature drop; when hammering the X / Y / Z surface of the steel ingot, by adjusting the frequency to 30-40 times / min, it can be ensured that the deformation is sufficient during the overall forging process but does not cause excessive cooling, and maintain the hot working performance of the material, and the setting of deformation rate of each hammer of the X surface ≥6% and deformation rate of each hammer of the Y / Z and corner surfaces ≥3% can evenly distribute the deformation in all directions, further optimize the internal structure of the steel ingot, reduce stress concentration, and form a more uniform grain structure; by using different forging first shots for different positions in the above forging process, the problems of cracked edges, cracks and uneven organization caused by improper forging frequency control in the prior art are solved, thereby improving the processing efficiency of GH4098 wide-width cold-rolled thin plates and the performance stability of the final products.

[0024] In a possible implementation, in step S3, the deformation rate of a single cold rolling process is ≤10%, and the deformation rate of a single cold rolling process is ≤35%.

[0025] Compared with the prior art, the above technical solution, by setting the deformation of a single pass to ≤10%, limits the deformation of a single pass, helps to avoid excessive processing stress in each cold rolling, prevents cracks or instability of the alloy plate due to strain concentration during the cold rolling process, and can also ensure that the grain structure inside the material is gradually homogenized after cold rolling, reducing the work hardening phenomenon during the deformation process; and limiting the deformation of a single cold rolling treatment to ≤35%, so that the work hardening during the cold rolling process is kept within a controllable range, which can prevent the material processing performance from decreasing and avoid the risk of fracture due to excessive total deformation. At the same time, this setting also helps to ensure the final thickness accuracy of the plate.

[0026] In a possible implementation, in step S3, the temperature of the solution heat treatment is 1150-1160° C., and the condition of the solution treatment of the finished product is to keep the temperature at 1155-1165° C. for 5 minutes.

[0027] Compared with the prior art, the above technical solution is set at 1150-1160°C, which is in the optimal solution temperature range of GH4098 alloy. This temperature range is sufficient to fully dissolve the γ′ strengthening phase, carbides (such as M23C6, WC, Mo2C, etc.) and other structures in the alloy into the matrix, improve the uniformity of the alloy matrix, and avoid excessive grain growth or coarsening of the structure due to high temperature; in the final solution treatment of the finished product, the temperature of 1155-1165°C is set to be kept for 5 minutes. Short-term heat preservation is conducive to the uniform dissolution of the strengthening phase and avoids abnormal grain growth. The brittleness increased due to enlargement or boundary coarsening, ensuring grain refinement and optimization of mechanical properties; during solution heat treatment, more attention is paid to the full dissolution of the strengthening phase, allowing the grains to grow moderately to improve the processability, but the influence of grain coarsening can be adjusted by controlling recrystallization in subsequent cold rolling, and in the solution treatment of the finished product, more attention is paid to the optimization of the final organization and performance. A moderate increase in temperature is conducive to moderate grain growth and organization homogenization, and improves the toughness of the material. Therefore, a slightly higher temperature is set to compensate for the influence of residual stress and work hardening on the organization performance during cold rolling, ensuring that the performance meets the final requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The blank is forged by conventional method; Figure 2 The blank obtained in step S1 of the method of the present invention; Figure 3 It is a cold rolled sheet produced by conventional method; Figure 4 A cold-rolled sheet prepared by the method of the present invention; Figure 5 It is a schematic diagram of the deformation process of forging in Example 1 and Example 2 of the present invention. DETAILED DESCRIPTION

[0029] First, those skilled in the art should understand that these implementations are only used to explain the technical principles of the embodiments of the present application, and are not intended to limit the protection scope of the embodiments of the present application. Those skilled in the art can make adjustments to them as needed to adapt to specific application scenarios.

[0030] The invention provides a cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet, comprising the following components by mass: Cr: 17.50-19.50%, Co: 5-8%, W: 5.5-7.0%, Mo: 3.5-5.0%, Al: 2.50-3.0%, Ti: 1.0-1.5%, Fe≤3.00%, Nb≤1.50%, Mn≤0.30%, Si≤0.30%, C≤0.10%, S≤0.015%, P≤0.015%, and the balance is Ni and other inevitable impurities.

[0031] Compared with the cold-rolled thin plates in the prior art, the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled thin plates provided by the present invention have the following key factors affecting the performance of the finished plates: as mentioned above, the chemical composition of the controlled steel ingot is first optimized. GH4098 is a cobalt-containing nickel-based alloy with a high gas content. In order to achieve sufficient degassing, improve the purity of the alloy, and improve the plasticity of the alloy, under normal circumstances, when smelting in a vacuum induction furnace, the insulation time is appropriately extended. While degassing, the surface evaporation of the metal molten pool is used to eliminate low-pressure harmful impurities such as lead, bismuth, tin, and antimony. When mixing the ingredients, the carbon is mixed to the upper and middle limits to facilitate the carbon-oxygen reaction under vacuum to fully degas; and combined with the requirements of the technical conditions for room temperature tensile strength, the content of strengthening elements is controlled at the lower and middle limits, and Be and Ce are added to strengthen the grain boundaries. From the perspective of forging and rolling, the effect is very good; As a preferred solution, the thickness of the cold-rolled sheet is 0.5±0.05 mm, the width is more than 1000 mm, and the performance parameters of the cold-rolled sheet at room temperature include: σb≤1180 MPa, δ5≥25%, and the grain size is 5-8 levels and the level difference cannot exceed 2.

[0032] The present invention also provides a method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled thin plate, comprising the following steps: S1: Forged slab A GH4098 alloy steel ingot is selected and forged to obtain a forged blank, wherein the chemical composition of the alloy steel ingot is the same as the chemical composition requirements of the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet; S2: Hot rolling The billet obtained in step S1 is heated and opened to obtain a GH4098 slab, which is then heated to a furnace temperature of 1200±10° C. by encapsulation, kept warm and the cooling water of the rolling mill is turned off, and then rolled to obtain a hot-rolled semi-finished product; In the above step S2, due to the certain gap between the furnace temperature and the material temperature, the material temperature is only about 1180℃ when heated in a furnace temperature of 1200℃, which is 20℃ lower than the theoretical temperature. In addition, the cooling water of the rolling mill causes the temperature to drop sharply during the rolling process. At the same time, due to the small length of the billet, a furnace plate is required to discharge the billet. The transportation process of the billet to the rolling mill and the removal of the furnace plate also cause the temperature to drop, making the already narrow optimal deformation temperature range even narrower, and correspondingly reducing the final rolling temperature. In the subsequent actual production, at a rolling temperature of 1200℃, sheath rolling was adopted and the cooling water of the rolling mill was turned off. At this time, even if the total deformation reaches 39%, the problem of edge cracking can be solved.

[0033] S3: Cold rolling The hot-rolled semi-finished product obtained in step S2 is subjected to solution heat treatment, pickling, and grinding in sequence, and then enters cold rolling treatment. When the total deformation of the hot-rolled semi-finished product reaches 30%, it is subjected to solution heat treatment again to soften the hot-rolled semi-finished product. Subsequently, the alternating operation of cold rolling treatment and solution heat treatment is repeated until the cold rolling is achieved to the desired thickness. After pickling and finishing again, the cobalt-containing nickel-based high-temperature alloy GH4098 wide-width cold-rolled sheet is obtained by solution treatment of the finished product.

[0034] As a preferred solution, in step S1, the forging method is: heating the GH4098 alloy steel ingot and then forging it into a forging blank by double-heat forging, and the heating temperature is 1200±10°C.

[0035] As a preferred solution, in the step S1, during the forging process, the hammering frequency is 30-45 times / min, and the final forging temperature is ≥1000°C.

[0036] As a preferred solution, in step S1, during the forging process, the frequency of hammering the edges of the steel ingot is 40-45 times / min, and the frequency of hammering the X / Y / Z surfaces of the steel ingot is 30-40 times / min, and when hammering the X surface, the deformation rate of each hammer is ≥6%, and when hammering the Y / Z / edge surface, the deformation rate of each hammer is ≥3%.

[0037] In the above step S1, the forging temperature is controlled at 1200°C, the forging frequency is fast with a light hammer to reduce heat loss as much as possible, and when hammering the corners, the hammer frequency is 40-45 times / min, and when hammering the X / Y / Z surfaces, 30-40 hammer frequencies / min are the best. The final forging temperature needs to be ≥1000°C, and when hammering the X surface, the deformation rate of each hammer is ≥6%, and when hammering the Y / Z / corner surface, the deformation rate of each hammer is ≥3%. This ensures that the temperature compensation and temperature loss of the X / Y / Z surface and the corner surface are minimized.

[0038] As a preferred solution, in step S3, the deformation rate of a single cold rolling process is ≤10%, and the deformation rate of a single cold rolling process is ≤35%.

[0039] As a preferred solution, in step S3, the temperature of the solution heat treatment is 1150-1160°C, and the condition of the solution treatment of the finished product is to keep the temperature at 1155-1165°C for 5 minutes.

[0040] Compared with the prior art, in the above step S2 / S3 of the present invention, the method of jacket rolling is adopted during hot rolling blanking, the purpose of which is to ensure the deformation temperature of hot rolling. When heated at a furnace temperature of 1200°C, the material temperature is only about 1180°C, which is 20°C lower than the theoretical temperature. In addition, the cooling water of the rolling mill causes the temperature to drop sharply during the rolling process. Therefore, the cooling water must be turned off during the rolling process to ensure that the hot-rolled semi-finished product does not produce edge cracks, thereby ensuring that the width of the finished product reaches 1000mm; such as the control of the solution heat treatment temperature of the finished product in the above step S3, due to the high strength of the GH4098 alloy, the room temperature tensile strength (σb) of the cold-rolled plate is very easy to exceed the standard, the room temperature tensile strength of the alloy decreases with the increase of the solution temperature, and the room temperature plasticity does not change significantly, but it is far higher than the standard requirements. When the GH4098 alloy is between 1105°C and 1160°C, its grain size slowly increases with the increase of the solution temperature. In this temperature range, the increase of the solution temperature has little effect on the grain size. Since room temperature tensile plasticity has a large margin, in order to meet standard requirements, a higher temperature (1150°C to 1160°C) can be used for solution treatment in actual production. Therefore, the present invention uses this solution temperature for pretreatment and then slightly increases the temperature for final solution treatment.

[0041] The following provides specific embodiments in combination with the data of the present invention to explain the scope of the technical solution of the present invention: Embodiment 1: This embodiment provides a wide cold-rolled sheet of a nickel-based high-temperature alloy GH4098 containing cobalt and a method for manufacturing the same. The wide cold-rolled sheet of the nickel-based high-temperature alloy GH4098 containing cobalt includes the following components in the following mass ratios: C: 0.090%, Mn: 0.25%, S: 0.011%, Co: 6.2%, Mo: 4.1%, Cr: 18.2%, Si: 0.20%, Fe: 2.3%, P: 0.009%, W: 6.1%, Ti: 1.13%, Al: 2.57%, Nb: 1.12%, and the balance is Ni and inevitable impurities.

[0042] The preparation steps of the above-mentioned cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled thin plate are as follows: S1: The steel ingot of the new cobalt-nickel-based high-temperature alloy GH4098 with a diameter of Φ350 is pre-hammered to 250 octagonal at the opening forging temperature of 1200℃±10℃, returned to the furnace, and after being taken out of the furnace, the four corners are pre-chamfered at a high temperature. After rapid chamfering, the Y direction is immediately deformed by a small amount of 250mm, and then the main deformation is carried out in the Z direction. It is immediately returned to the furnace when the temperature is lower than the final forging temperature. After being taken out of the furnace, the chamfering → Y direction edge deformation → Z direction main deformation are repeated. The forging frequency is to use light hammers and fast hammers to reduce heat loss as much as possible. When hammering the edges and corners, the hammer frequency is 40-45 times / min, and when hammering the X / Y / Z surfaces, the hammer frequency is 30-40 times / min. The final forging temperature must be ≥1000℃. When hammering the X surface, the deformation rate of each hammer is ≥6%, and when hammering the Y / Z / angle surfaces, the deformation rate of each hammer is ≥3%. A 60mmd slab can be obtained. The specific deformation process is as follows: Figure 5 As shown;

[0043] Compared with the prior art, the key factors affecting the width of the finished plate in the forging process of the above step S1 of the present invention are analyzed as follows: if the forging material is φ305 round steel ingot, which has a large diameter, it can be hammered to 250 octagonal angles on the hammer in advance due to slow cooling, and then returned to the furnace. After being taken out of the furnace, the four corners are pre-chamfered at a high temperature (to avoid sharp edges), and the Y direction is quickly deformed and trimmed by 250mm immediately after rapid chamfering, and then the main deformation is performed in the Z direction (this process cannot deform in the Y direction, increasing the risk of cracks), and the furnace is immediately returned to the furnace when the temperature is lower than the final forging temperature, and after being taken out of the furnace, the chamfering → Y direction trimming deformation → Z direction main deformation are repeated until the forging is reached. The billet obtained by this forging method has no cracks at all, creating good conditions for subsequent plate rolling.

[0044] S2: heating and blanking the slab in step S1 to obtain a GH4098 slab, heating the slab to 1200°C±10°C, keeping the temperature, turning off the cooling water of the rolling mill, and rolling to obtain a hot-rolled semi-finished product as a blank for a cold-rolled sheet; S3: The GH4098 hot-rolled semi-finished product obtained in step S2 is subjected to multiple cold rolling processes at 1150°C to 1160°C, pickled, and then cold rolled multiple times (solution heat treatment and pickling are added in the middle, and the process is the same as the hot-rolled semi-finished product). The single-pass deformation of the cold-rolled semi-finished product is controlled to be ≤10%, and the total deformation is controlled to be ≤35%. The solution temperature of the finished product is controlled to be kept at 1155-1165°C for 5 minutes, and a 0.5 mm thick cobalt-containing nickel-based high-temperature alloy GH4098 wide-width cold-rolled sheet is obtained.

[0045] Embodiment 2: This embodiment provides a wide cold-rolled sheet of a nickel-based high-temperature alloy GH4098 containing cobalt and a method for manufacturing the same. The wide cold-rolled sheet of the nickel-based high-temperature alloy GH4098 containing cobalt includes the following components in the following mass ratios: C=0.083%, Mn=0.22%, S=0.010%, Co=5.96%, Mo=4.12%, Cr=17.95%, Si=0.18%, Fe=2.24%, P=0.009%, W=6.17%, Ti=1.07%, Al=2.49%, Nb=1.09%, and the balance is Ni.

[0046] The preparation steps of the novel cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet are as follows: S1: The steel ingot of the new cobalt-nickel-based high-temperature alloy GH4098 with a diameter of Φ350 is pre-hammered to 250 octagonal at the opening forging temperature of 1200℃±10℃, and then returned to the furnace. After being taken out of the furnace, the four corners are pre-chamfered at a relatively high temperature. After rapid chamfering, the Y direction is immediately deformed by a small amount of 250mm, and then the main deformation is performed in the Z direction. When the temperature is lower than the final forging temperature, it is immediately returned to the furnace. After being taken out of the furnace, the chamfering → Y direction edge deformation → Z direction main deformation are repeated. The forging frequency is to use light hammers and fast hammers to reduce heat loss as much as possible. When hammering the corners, the hammer frequency is 40-45 times / min. When hammering the X / Y / Z surfaces, the hammer frequency is 30-40 times / min. The final forging temperature must be ≥1000℃. When hammering the X surface, the deformation rate of each hammer is ≥6%. When hammering the Y / Z / corner surfaces, the deformation rate of each hammer is ≥3%. A 60mmd slab can be obtained. The deformation process is as follows Figure 5 As shown:

[0047] S2: heating and blanking the slab in step S1 to obtain a GH4098 slab, heating the slab to 1200°C±10°C, keeping the temperature, turning off the cooling water of the rolling mill, and rolling to obtain a hot-rolled semi-finished product as a blank for a cold-rolled sheet; S3: The GH4098 hot-rolled semi-finished product obtained in step S2 is subjected to multiple cold rolling processes at 1150°C to 1160°C, pickled, and then cold rolled multiple times (solution heat treatment and pickling are added in the middle, and the process is the same as the hot-rolled semi-finished product). The single-pass deformation of the cold-rolled semi-finished product is controlled to be ≤10%, and the total deformation is controlled to be ≤35%. The solution temperature of the finished product is controlled to be kept at 1155-1165°C for 5 minutes to obtain a wide-width cold-rolled sheet of cobalt-containing nickel-based high-temperature alloy GH4098.

[0048] like Figure 1 , Figure 2 As shown, Figure 2 The blank is forged after being processed in step S1 of the above-mentioned embodiment 1 and embodiment 2 of the present invention. Figure 1 The blank is obtained by conventional forging method, such as Figure 3 , Figure 4 As shown, Figure 3 It is a cold-rolled sheet manufactured by conventional methods. Figure 4 The cold-rolled thin plate obtained in the above-mentioned embodiment 1 and embodiment 2 of the present invention is Figure 1 , Figure 2 as well as Figure 3 , Figure 4 It can be seen from the comparison that the improved forging process used in the present invention can significantly improve the surface flatness and uniformity of the billet, and significantly reduce the edge and surface crack defects of the billet; Figure 3 , Figure 4 It can be seen from the comparison that the cold-rolled sheet manufactured by the present invention has higher surface gloss and flatness than the cold-rolled sheet manufactured by the conventional method, and the grain structure inside the material is more uniform. This proves that the present invention can effectively solve the problems of billet cracks and plate surface defects in the conventional process through improved forging and cold rolling processes, while improving the quality stability of the cold-rolled sheet, providing technical guarantee for the manufacture of high-performance wide-width cold-rolled sheets.

[0049] The following table shows the grain size, tensile strength and elongation of the cold-rolled thin plates obtained in the above-mentioned embodiments 1 and 2 of the present invention. Table 1: Grain size, tensile strength and elongation of cold-rolled sheets obtained in Examples 1 and 2 The above table also further proves that: the grain size of Example 1 and Example 2 are both between 6.0 and 7.0, indicating that through the manufacturing method of the present invention, the grain size distribution of the material is relatively uniform, without significant over-coarse or over-fine grain phenomenon, and this uniform grain size helps to improve the mechanical stability and high temperature resistance of the material; the tensile strength (σb) of Example 1 is 1035MPa and 1032MPa respectively, and the tensile strength of Example 2 is 1080MPa and 1090MPa respectively, both of which meet and exceed the design requirements of cold-rolled thin plates (σb≤1180MPa). This shows that the tensile strength of the cobalt-containing nickel-based high-temperature alloy GH4098 can be effectively improved through the manufacturing process of the present invention; the elongation (δ5) of Example 1 and Example 2 is between 45% and 48% respectively, which is significantly higher than the materials manufactured by the industry or conventional processes (usually the elongation requirement is ≥25%). This good ductility indicates that the material has good plasticity while maintaining high strength and can withstand deformation requirements under complex working conditions; and the data variation range of the grain size, tensile strength and elongation of the two embodiments is small, indicating that the method of the present invention can ensure a high degree of consistency in material properties and avoid performance deviation problems caused by process fluctuations between batches.

[0050] The three key indicators of grain size, tensile strength and elongation further demonstrate that the manufacturing method of the present invention significantly improves the comprehensive performance of GH4098 wide-width cold-rolled thin plate, which not only meets the requirements of high strength and high plasticity, but also ensures the uniformity and stability of the performance, making it suitable for applications in aerospace and other high-end fields with extremely high performance requirements.

[0051] In the description of the present application, the description with reference to the terms "one embodiment", "some embodiments", "in the present embodiment", "specific example", or "some examples" etc. means that the specific features, mechanisms, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, mechanisms, materials or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0052] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A wide cold-rolled sheet of cobalt-containing nickel-based high-temperature alloy GH4098, characterized in that: It includes the following components by mass: Cr: 17.50-19.50%, Co: 5-8%, W: 5.5-7.0%, Mo: 3.5-5.0%, Al: 2.50-3.0%, Ti: 1.0-1.5%, Fe≤3.00%, Nb≤1.50%, Mn≤0.30%, Si≤0.30%, C≤0.10%, S≤0.015%, P≤0.015%, and the balance is Ni and other inevitable impurities.

2. The cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to claim 1, characterized in that: The thickness of the cold-rolled sheet is 0.5±0.05 mm, the width is more than 1000 mm, and the performance parameters of the cold-rolled sheet at room temperature include: σb≤1180 MPa, δ5≥25%, and the grain size is 5-8 levels and the level difference cannot exceed 2.

3. A method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to any one of claims 1-2, characterized in that: The following steps are involved: S1: Forged slab A GH4098 alloy steel ingot is selected and forged to obtain a forged blank, wherein the chemical composition of the alloy steel ingot is the same as the chemical composition requirements of the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet; S2: Hot rolling The billet obtained in step S1 is heated and opened to obtain a GH4098 slab, which is then heated to a furnace temperature of 1200±10° C. by encapsulation, kept warm and the cooling water of the rolling mill is turned off, and then rolled to obtain a hot-rolled semi-finished product; S3: Cold rolling The hot-rolled semi-finished product obtained in step S2 is subjected to solution heat treatment, pickling, and grinding in sequence, and then enters cold rolling treatment. When the total deformation of the hot-rolled semi-finished product reaches 30%, it is subjected to solution heat treatment again to soften the hot-rolled semi-finished product. Subsequently, the alternating operation of cold rolling treatment and solution heat treatment is repeated until the cold rolling is achieved to the desired thickness. After pickling and finishing again, the cobalt-containing nickel-based high-temperature alloy GH4098 wide-width cold-rolled sheet is obtained by solution treatment of the finished product.

4. The method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to claim 3, characterized in that: In the step S1, the forging method is: heating the GH4098 alloy steel ingot and then forging it into a forging blank by two-fire forging, and the heating temperature is 1200±10°C.

5. The method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to claim 4, characterized in that: In the step S1, during the forging process, the hammering frequency is 30-45 times / min, and the final forging temperature is ≥1000°C.

6. The method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to claim 5, characterized in that: In the step S1, during the forging process, the frequency of hammering the edges of the steel ingot is 40-45 times / min, and the frequency of hammering the X / Y / Z surfaces of the steel ingot is 30-40 times / min, and when hammering the X surface, the deformation rate of each hammer is ≥6%, and when hammering the Y / Z / edge surface, the deformation rate of each hammer is ≥3%.

7. The method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to claim 3, characterized in that: In the step S3, the deformation rate of a single cold rolling process is ≤10%, and the deformation rate of a single cold rolling process is ≤35%.

8. The method for manufacturing the cobalt-containing nickel-based high-temperature alloy GH4098 wide cold-rolled sheet according to claim 3, characterized in that: In step S3, the temperature of the solution heat treatment is 1150-1160° C., and the condition of the solution treatment of the finished product is to keep the temperature at 1155-1165° C. for 5 minutes.

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