Preparation method for improving carbide dispersion distribution of large-size GH4586 alloy bar and application

Abstract

The invention belongs to the technical field of metal material preparation, and relates to a preparation method for improving carbide dispersion distribution of a large-size GH4586 alloy bar and application. The method comprises the following steps: 1, carrying out triple smelting and homogenization treatment on a GH4586 alloy cast ingot to obtain a uniform cast ingot; secondly, the uniform cast ingot is subjected to first-time heating and heat preservation, then radial cogging forging is conducted, and an intermediate blank is obtained; thirdly, the middle blank is subjected to axial and radial alternate upsetting and drawing forming, and then the middle blank is subjected to secondary heating and heat preservation; and fourthly, the intermediate blank obtained after second-time heating and heat preservation is subjected to upsetting and drawing again, and the GH4586 alloy bar is obtained. The size of carbide in a cast ingot is refined through optimal design of the component proportion of a slag system in the electroslag smelting process. Meanwhile, by means of axial and radial alternate upsetting and drawing forming, tissues and carbides are fully crushed in different directions, and the dispersivity of carbide distribution and the uniformity of the tissues are improved.

Description

Technical Field

[0001] This invention belongs to the field of metal material preparation technology, and relates to a preparation method and application for improving the carbide dispersion distribution of large-size GH4586 alloy bars. Background Technology

[0002] GH4586 alloy is a typical age-hardening wrought superalloy. Its strengthening system is centered on carbides and the γ' phase, exhibiting excellent high-temperature strength and creep resistance through this strengthening mechanism. The carbide composition of this alloy mainly includes primary carbides MC and secondary carbides M6C and M... 23 C6; Among them, both carbides and γ' phases can effectively hinder dislocation movement and grain boundary migration by pinning grain boundaries, which not only significantly improves the overall strength of the alloy, but also inhibits recrystallization and grain growth, ensuring the structural stability of the alloy under high-temperature conditions. However, in the actual production and application of GH4586 alloy bars, there has long been a critical problem of carbide segregation and banding distribution. This problem directly and severely restricts the service life of key engine components, specifically in two aspects: First, during long-term engine service, cracks tend to propagate preferentially along the carbide banding region, significantly reducing the component's resistance to failure; Second, during the heat treatment process, the carbide banding region maintains a fine-grained structure due to the inhibitory effect of carbides, while areas with less carbide content exhibit significant grain growth, ultimately leading to an uneven structure of coarse and fine grain bands, further affecting the consistency of component performance. To address the aforementioned technical challenges, the inventors hereby propose a method for preparing large-size GH4586 alloy bars. The core objective is to improve the carbide distribution and achieve a dispersed distribution of carbides, thereby providing technical support for improving the performance of alloy bars and extending the service life of key engine components. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and to propose a preparation method and application for improving the carbide dispersion distribution of large-size GH4586 alloy bars.

[0004] On the one hand, such as Figure 1 As shown, this invention discloses a method for improving the carbide dispersion distribution in large-size GH4586 alloy bars, comprising the following steps: Step 1: Perform three-stage smelting and homogenization treatment on the GH4586 alloy ingot to obtain a uniform ingot. Step 2: Perform radial forging on the uniform ingot 2-3 times to obtain intermediate billet; Step 3: Alternately upset the intermediate billet in the axial and radial directions to obtain a preformed billet; Step four, the preform is again axially upset formed to obtain a GH4586 alloy bar.

[0005] Further, in step one, the triple smelting is that the GH4586 alloy ingot is first vacuum induction melted to form an induction ingot, then the surface of the induction ingot is subjected to light cutting treatment, and then the induction ingot after the light cutting treatment is subjected to electroslag remelting to obtain an electroslag ingot; finally, the electroslag ingot is subjected to vacuum consumable melting.

[0006] Further, in the vacuum induction melting process, the refining temperature is 1490-1550℃, and the casting temperature is 1430-1480℃.

[0007] Specifically, the refining temperature can be 1490℃, 1500℃, 1540℃, 1550℃, and the specific temperature can be adjusted according to the actual situation; the casting temperature can be 1430℃, 1440℃, 1450℃, 1460℃, 1470℃, 1480℃, and the specific temperature can be adjusted according to the actual situation.

[0008] Further, in the vacuum induction melting process, the slag system components used in electroslag remelting are: 52-61% CaF2, 21-25% CaO, 10-25% Al2O3, 2-5% TiO2, 2-6% MgO, 0.5-3% ZrO2, 0.5-2% SiO2, and the melting rate in the stable stage of electroslag remelting is 210 kg / h-220 kg / h.

[0009] Specifically, CaF2 can be 52%, 53%, 54%, … 61%; CaO can be 21%, 22%, 23%, 24%, 25%; Al2O3 can be 10%, 11%, 12%, … 23%, 24%, 25%; TiO2 can be 2%, 3%, 4%, 5%; MgO can be 2%, 3%, 4%, 5%, 6%; ZrO2 can be 0.5%, 1%, 1.5%, 2%, … 5%; SiO2 can be 0.5%, 1%, 1.5%, 2%, and the above data can be adjusted according to actual needs, and the proportions of CaF2, CaO, Al2O3, TiO, MgO, ZrO2, and SiO2 add up to 100%; Further, in step two, a stepped heating method is used, and the heating temperature is 850-1210℃.

[0010] Specifically, the heating temperature is 850℃, 900℃, 950℃, 1000℃, 1050℃, 1100℃, 1150℃, 1200℃, 1210℃, and the specific temperature can be adjusted according to actual needs.

[0011] Further, in step two, the radial open-die forging is performed by using an 80MN fast forging machine, and the forging is performed for 2-3 times, and the deformation mode of the radial open-die forging is circle→octagon→hexadecagon→circle, and the deformation amount is controlled to be 15%-25%.

[0012] Specifically, each time of the radial open-die forging in step two is first heated and kept, then forged out of the furnace, and finally returned to the furnace for keeping.

[0013] Further, in step three, the alternating upsetting and drawing forming is performed by using an 80MN fast forging machine, and a total of 2-3 cycle forgings are performed, wherein each cycle forging includes 1 time of axial upsetting, 1 time of radial drawing and round processing, the deformation amount of the axial upsetting is controlled to be 30%-40%, and the deformation amount of the radial drawing is controlled to be 30-40%.

[0014] Specifically, each time of the axial upsetting and the radial drawing is first heated and kept, then forged out of the furnace, and finally returned to the furnace for keeping.

[0015] Further, in step three, in the axial upsetting, the radial drawing and the round processing, the heating temperature of each time is 1080℃-1120℃, and the keeping time is 90min-240min.

[0016] Further, in step four, in the axial upsetting and drawing forming process, the heating temperature is 1020℃-1100℃, the keeping time is 60min-180min, and the deformation amount of each time of upsetting or drawing is controlled to be 30%-45%.

[0017] On the other hand, the application also discloses the GH4586 alloy rod prepared by the preparation method.

[0018] Compared with the prior art, the application has the following beneficial effects: (1) The application proposes that the GH4586 alloy is prepared by using the vacuum induction+electroslag remelting+vacuum consumable process to replace the traditional vacuum induction+vacuum consumable process, through the optimization design of the component proportioning of the slag system in the electroslag melting process, the nanometer scale oxide particles existing in the ingot in the electroslag melting process can be used as carbide nucleation points, which is helpful to refine the carbide size in the ingot and improve the dispersion of the carbide distribution in the ingot; (2) The present application proposes a process of radial breakdown forging + axial and radial alternating upsetting and drawing forming + finished product forging of large-size GH4586 ingot. Compared with the traditional axial high-temperature breakdown forging process, there is a bidirectional tensile stress in the radial breakdown process along the diameter direction, and the bidirectional tensile stress is better in the crushing effect of carbides in the repeated forging process, so that the carbide strips distributed along the axial dendrites in the ingot are fully crushed, and the intermediate billet with optimized distribution of carbides is obtained. Subsequently, the axial and radial alternating upsetting and drawing forming process is adopted, and the structure and carbides are fully crushed in different directions, so that the problems of carbide strips and aggregation caused by the elongation in a single direction in the traditional preparation process are solved. BRIEF DESCRIPTION OF DRAWINGS

[0019] The drawings incorporated into the specification and constituting a part of the specification, together with the specification, serve to explain the principles of the present application.

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows, and obviously, other drawings can also be obtained by those skilled in the art without creative labor.

[0021] Figure 1 is a flow chart of the preparation method of the present application; Figure 2 is a microstructure diagram of 1 / 2 radius of GH4586 alloy bar with a specification of Φ350mm prepared by the embodiment 1 of the present application; Figure 3 is a microstructure diagram of 1 / 2 radius of GH4586 alloy bar with a specification of Φ300mm prepared by the embodiment 2 of the present application; Figure 4 is a microstructure diagram of 1 / 2 radius of GH4586 alloy bar with a specification of Φ250mm prepared by the embodiment 3 of the present application; Figure 5 is a microstructure diagram of 1 / 2 radius of GH4586 alloy bar with a specification of Φ300mm prepared by the comparative example 1 of the present application. DETAILED DESCRIPTION

[0022] Here, the exemplary embodiments will be described in detail, and the embodiments described in the following exemplary embodiments do not represent all the embodiments consistent with the present application. Instead, they are only examples consistent with some aspects of the present application as described in the appended claims.

[0023] In order to make those skilled in the art better understand the technical solutions of the present application, the present application will be further described in detail below with reference to the drawings and embodiments.

[0024] Example 1 (preparation of GH4586 high-temperature alloy bar with a specification of Φ350 mm) Step one, triple smelting and homogenization treatment of GH4586 alloy ingot to obtain a uniform ingot; Specifically, the triple smelting adopts the smelting process of induction melting + electroslag remelting + vacuum consumable remelting to sequentially smelt, wherein the refining temperature of vacuum induction melting is controlled at 1490℃, and the casting temperature is controlled at 1480℃; the slag ratio of electroslag remelting is 52% CaF2, 25% CaO, 15% Al2O3, 3% TiO2, 3% MgO, 1% ZrO2, 1% SiO2, and the melting rate in the stable stage is 220 kg / h; the melting rate in the stable stage of vacuum consumable smelting is 3.2 kg / min, and finally a GH4586 high-temperature alloy ingot with a diameter of Φ508 mm is obtained.

[0025] Specifically, the GH4586 high-temperature alloy ingot obtained in step one is first subjected to high-temperature homogenization treatment by using a natural gas furnace to promote the full diffusion of each element, and the specific process is divided into the following four continuous stages: First stage: heat the GH4586 high-temperature alloy ingot to 850℃ and keep for 360 min; Second stage: after the first stage is completed, immediately heat the GH4586 high-temperature alloy ingot to 1000℃ at a heating rate of 5℃ / min and keep for 400 min; Third stage: after the second stage is completed, immediately heat the GH4586 high-temperature alloy ingot to 1160℃ at a heating rate of 5℃ / min and keep for 2500 min; Fourth stage: after the third stage is completed, immediately heat the GH4586 high-temperature alloy ingot to 1210℃ at a heating rate of 6℃ / min and keep for 3500 min, and then air cool after the holding is completed.

[0026] Step two, 2-3 fire radial breakdown forging of the uniform ingot to obtain an intermediate blank; Specifically, the GH4586 high-temperature alloy ingot after high-temperature homogenization treatment is subjected to 2-fire continuous back furnace radial breakdown forging by using an 80MN fast forging machine, the first fire heating temperature is 1180℃, the holding time is 420 min, the second fire heating temperature is 1160℃, the holding time is 180 min, the hammer anvil width of the fast forging machine is 900 mm, the whole ingot is placed horizontally under the hammer anvil during forging, in order to reduce the deformation dead zone, the deformation mode is circular → octagonal → round deformation mode, the first fire deformation amount is 15%, and the second fire deformation amount is 25%.

[0027] Step three, alternating upsetting and drawing of the intermediate blank in the axial and radial directions to obtain a preformed blank; Specifically, the intermediate blank after radial cogging is processed by 1 fire axial upsetting + 1 fire radial elongation + rounding as a cycle, 3 cycles of axial and radial alternating upsetting and drawing forming, a total of 6 fires, wherein the heating temperature of 1-2 fires is 1120 DEG C, the holding time is 240 min, the deformation of axial upsetting and radial elongation is 30%; the heating temperature of 3-4 fires is 1100 DEG C, the holding time is 160 min, the deformation of axial upsetting and radial elongation is 35%; the heating temperature of 5-6 fires is 1080 DEG C, the holding time is 90 min, the deformation of axial upsetting and radial elongation is 40%.

[0028] Step four, the preformed blank is again axially upset and drawn to obtain a GH4586 alloy rod.

[0029] Specifically, the intermediate blank after alternating upsetting and drawing is formed along the axial direction by 1 fire upsetting + 1 fire elongation forming, the upsetting temperature is 1100 DEG C, the holding time is 180 min, the deformation is 30%, the elongation temperature is 1060 DEG C, the holding time is 120 min, the deformation is 45%, thereby obtaining a Φ350mm specification GH4586 alloy rod with dispersed carbides.

[0030] Example 2 (preparation of GH4586 high-temperature alloy rod with a specification of Φ300mm) The purpose of the embodiment of the present application is to prepare a GH4586 high-temperature alloy rod blank with a diameter of Φ300mm, and the specific preparation process is as follows: Step one, three-link smelting and homogenization treatment are performed on the GH4586 alloy ingot to obtain a uniform ingot; 1) The smelting process of vacuum induction melting + electroslag remelting + vacuum consumable remelting is sequentially carried out, the refining temperature of induction melting is controlled at 1550 DEG C, and the casting temperature is controlled at 1430 DEG C; the slag ratio of electroslag remelting is 56% CaF2, 23% CaO, 13% Al2O3, 2% TiO2, 2% MgO, 2% ZrO2, 2% SiO2, and the melting rate in the stable stage is 215 kg / h. The melting rate in the stable stage of vacuum consumable melting is 3.2 kg / min. Finally, a GH4586 high-temperature alloy ingot with a diameter of Φ508mm is obtained.

[0031] The GH4586 high-temperature alloy ingot obtained in step one is subjected to high-temperature homogenization treatment by using a natural gas furnace to promote the full diffusion of each element, and the specific process is divided into the following four continuous stages: First stage: heat the GH4586 high-temperature alloy ingot to 850 DEG C and keep for 360 min; Second stage: after the first stage, the GH4586 high-temperature alloy ingot is heated to 1000℃ at a heating rate of 5℃ / min, and the temperature is kept for 400min; Third stage: after the second stage, the GH4586 high-temperature alloy ingot is heated to 1160℃ at a heating rate of 5℃ / min, and the temperature is kept for 2500min; Fourth stage: after the third stage, the GH4586 high-temperature alloy ingot is heated to 1210℃ at a heating rate of 6℃ / min, and the temperature is kept for 3500min, and then air cooling is performed after the temperature keeping.

[0032] Step two: the uniform ingot is subjected to 2-3 times of radial open-die forging to obtain an intermediate blank; Specifically, the 80MN fast forging machine is used to perform 2 times of continuous re-melting radial open-die forging on the GH4586 high-temperature alloy ingot after high-temperature homogenization treatment, the first heating temperature is 1180℃, the holding time is 420min, the second heating temperature is 1160℃, the holding time is 150min, the hammer anvil width of the fast forging machine is 900mm, the whole ingot is placed horizontally under the hammer anvil during forging, in order to reduce the deformation dead zone, the deformation mode is circular→octagonal→rounding deformation mode, the first deformation amount is 15%, and the second deformation amount is 20%.

[0033] Step three: the intermediate blank is subjected to alternating upsetting and drawing forming in the axial and radial directions to obtain a pre-formed blank; Specifically, the 80MN fast forging machine is used to perform 1 time of axial upsetting+1 time of radial drawing+rounding treatment as one cycle, and the axial and radial alternating upsetting and drawing forming is performed for 3 cycles, a total of 6 times, wherein the heating temperature of 1-2 times is 1120℃, the holding time is 240min, and the deformation amount of axial upsetting and radial drawing is 30%; the heating temperature of 3-4 times is 1100℃, the holding time is 160min, and the deformation amount of axial upsetting and radial drawing is 35%; the heating temperature of 5-6 times is 1080℃, the holding time is 90min, and the deformation amount of axial upsetting and radial drawing is 35%.

[0034] Step four: the pre-formed blank is subjected to axial upsetting and drawing forming again to obtain a GH4586 alloy rod.

[0035] Specifically, the 80MN fast forging machine is used to perform 1 time of drawing forming along the axial direction, the heating temperature is 1040℃, the holding time is 90min, and the drawing deformation amount is 40%, thereby obtaining a Φ300mm specification GH4586 alloy rod with dispersed carbides.

[0036] Example 3 (preparation of GH4586 high-temperature alloy rod with a specification of Φ250mm) The embodiment of the present application aims to prepare a GH4586 high-temperature alloy rod with a diameter of Φ250mm, and the specific preparation process is as follows: Step one, triple smelting and homogenization treatment are performed on the GH4586 alloy ingot to obtain a uniform ingot. Specifically, vacuum induction melting + electroslag remelting + vacuum consumable remelting smelting process is sequentially performed, the refining temperature of induction melting is controlled at 1520℃, and the pouring temperature is controlled at 1450℃; the slag ratio of electroslag remelting is 58% CaF2, 21% CaO, 10% Al2O3, 3% TiO2, 3% MgO, 3% ZrO2, 2% SiO2, and the melting speed in the stable stage is 210kg / h. The melting speed in the stable stage of vacuum consumable melting is 3.2kg / min, and finally a GH4586 high-temperature alloy ingot with a diameter of Φ508mm is obtained.

[0037] The GH4586 high-temperature alloy ingot obtained in step one is subjected to high-temperature homogenization treatment by using a natural gas furnace to promote the full diffusion of each element, and the specific process is divided into the following four continuous stages as follows: First stage: the GH4586 high-temperature alloy ingot is heated to 850℃ and kept for 360min; Second stage: after the first stage is completed, the GH4586 high-temperature alloy ingot is immediately heated to 1000℃ at a heating rate of 5℃ / min and kept for 400min; Third stage: after the second stage is completed, the GH4586 high-temperature alloy ingot is immediately heated to 1160℃ at a heating rate of 5℃ / min and kept for 2500min; Fourth stage: after the third stage is completed, the GH4586 high-temperature alloy ingot is immediately heated to 1210℃ at a heating rate of 6℃ / min and kept for 3500min, and then air-cooled after the keeping is completed.

[0038] Step two, the uniform ingot is subjected to 2-3 times of radial breakdown forging to obtain an intermediate blank. Specifically, the GH4586 high-temperature alloy ingot after high-temperature homogenization treatment is subjected to 3 times of continuous back furnace radial breakdown forging by using an 80MN fast forging machine, the heating temperature of the first fire is 1180℃, the holding time is 420min, the heating temperature of the second fire is 1160℃, the holding time is 150min, the heating temperature of the third fire is 1160℃, the holding time is 120min, the hammer anvil width of the fast forging machine is 900mm, the whole ingot is placed horizontally under the hammer anvil during forging, in order to reduce the deformation dead zone, the deformation mode is circular→octagonal→round deformation mode, the deformation amount of the first fire is 15%, the deformation amount of the second fire is 20%, and the deformation amount of the third fire is 25%.

[0039] Step three, the intermediate blank is alternately formed by axial upsetting and radial drawing to obtain a preformed blank; Specifically, the intermediate blank subjected to radial breakdown forging is subjected to 1-fire axial upsetting + 1-fire radial drawing + roundness processing as one cycle, and is subjected to 2 cycles of axial and radial alternating upsetting and drawing, a total of 4 fires, wherein the heating temperature of 1-2 fires is 1100℃, the holding time is 160min, and the deformation of axial upsetting and radial drawing is 35%; the heating temperature of 3-4 fires is 1080℃, the holding time is 90min, and the deformation of axial upsetting and radial drawing is 40%.

[0040] Step four, the preformed blank is again formed by axial upsetting and drawing to obtain a GH4586 alloy rod.

[0041] Specifically, the intermediate blank is subjected to 1-fire drawing along the axial direction by using an 80MN fast forging machine, the heating temperature is 1020℃, the holding time is 60min, and the drawing deformation is 45%, thereby obtaining a Φ250mm specification GH4586 alloy rod with dispersed distribution of carbides.

[0042] Comparative Example 1 (preparing a GH4586 high-temperature alloy rod with a specification of Φ300mm) 1) The smelting process of vacuum induction melting + vacuum consumable remelting + vacuum consumable remelting is sequentially carried out, the refining temperature of induction melting is controlled at 1490-1550℃, and the pouring temperature is controlled at 1430-1480℃; the melting speed in the stable stage is 210kg / h-220kg / h. The melting speed in the stable stage of vacuum consumable melting is 3.2kg / min, and finally a GH4586 high-temperature alloy ingot with a diameter of Φ508mm is obtained.

[0043] 2) The GH4586 high-temperature alloy ingot obtained in step 1) is subjected to high-temperature homogenization treatment by using a natural gas furnace to promote the full diffusion of each element, and the specific process is divided into the following four continuous stages as follows: First stage: heat the GH4586 high-temperature alloy ingot to 750℃ and keep for 360min; Second stage: after the first stage is completed, immediately heat the GH4586 high-temperature alloy ingot to 990℃ at a heating rate of 3℃ / min and keep for 400min; Third stage: after the second stage is completed, immediately heat the GH4586 high-temperature alloy ingot to 1130℃ at a heating rate of 5℃ / min and keep for 2500min; Fourth stage: after the third stage is completed, immediately heat the GH4586 high-temperature alloy ingot to 1170℃ at a heating rate of 6℃ / min and keep for 3500min, and then air cool after the holding is completed.

[0044] 3) using 80MN fast forging machine, the GH4586 high-temperature alloy ingot after the step 3) high-temperature homogenization treatment is forged for 8 times of continuous back furnace forging, wherein the forging temperature of the first 4 times is 1170℃, the forging temperature of the 5th to 6th times is 1120℃, and the forging temperature of the 7th to 8th times is 1100℃, and the specific forging process parameters are shown in Table 1 below: Table 1: forging process parameters of comparative example 1 Result analysis: Figure 2 is the microstructure of the Φ350mm specification bar R / 2 of example 1, Figure 3 is the microstructure of the Φ300mm specification bar R / 2 of example 2, Figure 4 is the microstructure of the Φ250mm specification bar R / 2 of example 3, combined with the optimization design of the melting and forging process, the three specifications of GH4586 bars prepared have good uniformity and consistency of the microstructure, the carbide distribution is relatively dispersed, and no obvious carbide strip aggregation problem is found.

[0045] As a comparison, Figure 5 is the microstructure of the Φ300mm specification GH4586 bar without optimization in the comparative example, compared with Figure 3 the grain size is relatively coarse and there is obvious carbide strip.

[0046] The above description is only a specific embodiment of the present application, which enables those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application.

[0047] It should be understood that the present application is not limited to the above described and that various modifications and changes can be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A method for improving the carbide dispersion distribution in large-size GH4586 alloy bars, characterized in that, Includes the following steps: Step 1: Perform three-stage smelting and homogenization treatment on the GH4586 alloy ingot to obtain a uniform ingot. Step 2: Perform radial forging on the uniform ingot 2-3 times to obtain intermediate billet; Step 3: Alternately upset the intermediate billet in the axial and radial directions to obtain a preformed billet; Step 4: The preformed billet is axially uptaken again to obtain GH4586 alloy bar.

2. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 1, characterized in that, The three-stage smelting process in step one involves first performing vacuum induction melting on the GH4586 alloy ingot to form an induction ingot, then polishing the surface of the induction ingot, followed by electroslag remelting of the polished induction ingot to obtain an electroslag ingot, and finally performing vacuum arc remelting on the electroslag ingot.

3. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 2, characterized in that, During the vacuum induction melting process, the refining temperature is 1490~1550℃ and the casting temperature is 1430~1480℃.

4. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 2, characterized in that, During vacuum induction melting, the slag system used in electroslag remelting consists of: 52-61% CaF2, 21-25% CaO, 10-25% Al2O3, 2-5% TiO2, 2-6% MgO, 0.5-3% ZrO2, and 0.5-2% SiO2. The melting rate during the stable stage of electroslag remelting is 210 kg / h to 220 kg / h.

5. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 1, characterized in that, In step two, radial billet forging is carried out using an 80MN high-speed forging machine, with 2 to 3 forging passes. The radial billet forging adopts a deformation method of round → octagon → hexagon → round, and the deformation amount is controlled at 15% to 25%.

6. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 1, characterized in that, In step three, alternating upsetting and drawing is completed using an 80MN fast forging machine, with a total of 2 to 3 forging cycles. Each forging cycle includes one axial upsetting, one radial drawing, and rounding. The deformation amount of the axial upsetting is controlled at 30% to 40%, and the deformation amount of the radial drawing is controlled at 30% to 40%.

7. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 6, characterized in that, In the axial upsetting, radial drawing and rounding processes, the heating temperature for each heat treatment is 1080℃~1120℃, and the holding time is 90min~240min.

8. The preparation method for improving the carbide dispersion distribution of large-size GH4586 alloy bars according to claim 1, characterized in that, In step four, during the axial upsetting and drawing process, the heating temperature is 1020℃~1100℃, the holding time is 60min~180min, and the deformation of upsetting or drawing per heat is controlled at 40%~45%.

9. A GH4586 alloy bar prepared by the preparation method according to any one of claims 1 to 8, used in the preparation of aero-engine turbine disks.

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