Nickel-based alloy forged bar and preparation method thereof

Abstract

The invention relates to the technical field of alloy processing, and particularly discloses a nickel-based alloy forged bar and a preparation method thereof. The nickel-based alloy forged bar is prepared from 0.05%-0.1% of C, 0.2%-0.5% of Mn, 3%-4% of Al, 0.2%-0.4% of Si, 0.3%-0.5% of Ti, 1%-2% of Nb, 25%-31% of Cr, 0.1%-0.31% of Cu, 0.0003%-0.001% of S, 4.0%-5.3% of Fe and the balance Ni and inevitable impurities. According to the nickel-based alloy forged bar, chemical components are adjusted, the forging technology of the bar is limited, the nickel-based alloy forged bar with high strength and high plasticity is prepared, and the problem that N06693 nickel-based alloy is prone to cracking in the preparation process is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the alloy processing technical field, and specifically discloses a nickel-based alloy forged bar and a preparation method thereof. BACKGROUND

[0002] N06693 alloy is a new type of nickel-based corrosion-resistant high-temperature alloy, which is obtained by adding Al and Ti elements on the basis of N06690 alloy. Under annealing conditions, N06693 alloy exhibits a single solid solution disorder face-centered cubic (fcc) austenite (gamma) phase, which improves the strength of the alloy, and the addition of Al can improve the high-temperature corrosion resistance.

[0003] However, N06693 alloy also has obvious performance short board, when forging deformation at 950℃, very fine gamma prime phase particles will be precipitated in the gamma phase, which will cause the alloy to fail in a brittle manner, specifically manifested as cracking of the forged bar; in addition, after solution treatment of the alloy, the cooling rate is relatively strict, if cooled at a cooling rate lower than 4500℃ / min, more gamma prime phase particles will be formed at a temperature lower than 950℃, which will bring serious strain to the matrix and reduce the plasticity during deformation, ultimately leading to transgranular brittle cracking of the alloy during deformation. Due to the need for rapid cooling after alloy hot deformation to avoid cracking, this higher production requirement makes the alloy rarely produced in China. SUMMARY

[0004] Therefore, the present application provides a nickel-based alloy forged bar and a preparation method thereof. The nickel-based alloy forged bar provided by the present application is prepared by adjusting the chemical composition and limiting the forging process of the bar, and has high strength and high plasticity, avoiding the problem of easy cracking of N06693 nickel-based alloy during preparation.

[0005] To achieve the above-mentioned application purposes, the present application provides the following technical solutions.

[0006] The present application provides a nickel-based alloy forged bar, which comprises the following chemical components in mass percentage: C: 0.05%-0.1%, Mn: 0.2%-0.5%, Al: 3%-4%, Si: 0.2%-0.4%, Ti: 0.3%-0.5%, Nb: 1%-2%, Cr: 25%-31%, Cu: 0.1%-0.31%, S: 0.0003%-0.001%, Fe: 4.0%-5.3%, and the balance is Ni and inevitable impurities.

[0007] Compared with the prior art, the nickel-based alloy forged bar provided by the application can form a dense aluminum oxide film on the surface of the bar due to the specific content of aluminum element, thereby slowing down the oxidation rate of the bar, inhibiting the invasion of elements such as sulfur, and improving the corrosion resistance of the bar; in addition, the addition of the aluminum element can also form stable strengthening phases at high temperatures, and these strengthening phases can effectively hinder the dislocation movement between grains, thereby improving the high-temperature strength of the bar; the specific content of carbon element and niobium element can form stable carbides, and these carbides can be pinned to the grain boundary to inhibit grain growth, thereby improving the strength and creep resistance; and the niobium element can refine the grain structure of the bar, increase the number of grains, and inhibit the formation of harmful phases, thereby improving the strength and toughness of the bar. The manganese element and the iron element can optimize the toughness of the matrix and reduce the sliding resistance; in addition, the inventor found in the research process that the specific content of the manganese element dissolved in the alloy matrix will not cause large distortion to the lattice of the bar matrix, thereby balancing the strength and plasticity of the bar. The titanium, nickel and aluminum elements form nanoscale γ' phases, which significantly improve the strength of the bar by hindering the dislocation movement of the grain structure, and the nanoscale γ' phases have low lattice mismatch with the alloy matrix of the bar, thereby avoiding the cracking problem caused by excessive brittleness of the bar; the specific content of the copper element dissolved in the bar matrix will cause slight lattice distortion to the matrix to improve the strength of the bar, and since the addition amount is small, the bar also has good toughness.

[0008] The application balances the strength and plasticity of the nickel-based alloy forged bar by reasonably optimizing the chemical composition and component ratio of the nickel-based alloy forged bar, and the bar is not prone to cracking during the forging process.

[0009] The application provides a preparation method of the above-mentioned nickel-based alloy forged bar, which comprises the following steps:

[0010] S1, heat the ingot at 1120-1150 DEG C, upset the ingot after heat preservation, and elongate the ingot to obtain a first treated ingot;

[0011] S2, heat the first treated ingot at 1110-1130 DEG C, elongate the ingot after heat preservation to obtain a second treated ingot;

[0012] S3, heat the second treated ingot at 1090-1120 DEG C, wrap the ingot with ceramic fibers after heat preservation, elongate the ingot, air cool, and heat treat to obtain a nickel-based alloy forged bar.

[0013] Compared with the prior art, the preparation method of the nickel-based alloy forged bar provided by the application has the advantages that: in the preparation method, the cast ingot is kept at a specific temperature, which can provide a good plasticity basis for subsequent upsetting and elongating forging by homogenizing the metal composition and reducing internal stress; the upsetting forging can compact the internal defects such as porosity and shrinkage cavity of the cast ingot, so as to densify the metal; the elongating forging can break the coarse as-cast grain structure by plastic deformation, so that the grain structure in the cast ingot is changed from the as-cast grain structure to the forged grain structure, and the plasticity and strength of the cast ingot are preliminarily improved, and early cracking caused by the embrittlement of the as-cast structure can be avoided.

[0014] In S2, keeping at a specific temperature can ensure the plasticity of the second processed cast ingot, and then through elongating forging, the grain structure is fully refined, the broken grain structure is uniformly distributed along the deformation direction, the grain boundary bonding force is strengthened, the strength is improved, the plasticity is improved, and the problem of cracks in the bar caused by insufficient plasticity during forging is avoided; in addition, the grain structure is fully refined, which prepares for obtaining uniform equiaxed grains in the subsequent process.

[0015] In S3, after keeping at a specific temperature, the elongating forging is performed, the grain structure in the second processed cast ingot is changed into fibrous grain structure, and the grain structure has a high internal energy state because it contains a large number of dislocations and grain boundary distortions; during the forging process, heat is generated, the grain structure reduces defects by dislocation movement and combination to lay a foundation for recrystallization; when the forging reaches a certain degree, there is no dislocation new grain nucleus in the fibrous grain interior or grain boundary, and equiaxed grain structure is formed through recrystallization to eliminate deformation defects, and then the grain structure grows to a specific size to realize the transformation from fibrous grain structure to equiaxed grain structure, and the performance of the bar is ensured. Wrapping the cast ingot with ceramic fibers after the keeping can realize slow cooling, reduce thermal stress and organizational stress in the cooling process, eliminate residual stress, and ensure that the bar does not crack during elongating forging.

[0016] In S1, the cast ingot is obtained by vacuum induction and electroslag remelting process on the raw material.

[0017] Preferably, in S1, the diameter of the cast ingot is 480mm-500mm.

[0018] Preferably, in S1, the cast ingot comprises the following pretreatment steps: keeping at 1000℃-1150℃ for 3h-5h, and after the keeping, performing a press pinch handle treatment to obtain a cast ingot with a tail part with a pinch handle.

[0019] The press pinch handle treatment can detect the deformation resistance and plasticity of the cast ingot at the heating temperature, and prepare for the subsequent elongating treatment.

[0020] Preferably, in S1, the keeping time is 1h-2h.

[0021] Preferably, in S1, the upsetting ratio of the upsetting forging is 1.45-1.55.

[0022] Preferably, in S1, the drawing ratio of the drawing forging is 1.89-2.1.

[0023] By limiting the specific parameters of the upsetting forging and the drawing forging, the plasticity of the ingot is improved, and the plasticity of subsequent forging is improved.

[0024] Illustratively, in S1, the cross-sectional area of the first processed ingot is square.

[0025] Preferably, in S2, the holding time is 1-2 hours.

[0026] Preferably, in S2, the drawing ratio of the drawing forging is 1.66-1.9.

[0027] The preferred parameters of the drawing forging are advantageous for further improving the plasticity and strength of the rod and avoiding cracking of the rod.

[0028] Illustratively, in S2, the cross-sectional area of the second processed ingot is square.

[0029] Preferably, in S3, the holding time is 1-1.5 hours.

[0030] Preferably, in S3, the drawing ratio of the drawing forging is 1.94-2.

[0031] The present application further limits the parameters of the drawing forging in S3, which can ensure that the rod forms a specific size of equiaxed grain structure, so that the prepared rod has high strength and plasticity, and ensures that the rod does not crack during heat treatment.

[0032] Preferably, in S3, the cladding thickness of the ceramic fiber is 5-10 mm.

[0033] Preferably, in S3, the heat treatment conditions are: holding at 1050-1150 DEG C and then water cooling, and then holding at 800-810 DEG C and then air cooling.

[0034] The inventors have found through a large number of studies that for the ingot under the above forging conditions, the heat treatment conditions are advantageous for further optimizing the performance of the nickel-based alloy forged rod.

[0035] Preferably, the holding time at 1050-1150 DEG C is 60-90 min.

[0036] Preferably, the holding time at 800-810 DEG C is 360-380 min.

[0037] The present application makes the prepared nickel-based alloy forged rod have high strength and excellent plasticity, and does not have the problem of cracking in the production process, solves the problems of high production condition requirement and easy alloy cracking of the existing N06693 alloy. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 The microstructure diagram of the ingot in the embodiment 1 of the present application is shown in the figure.

[0039] Figure 2 The microstructure diagram of the nickel-based alloy forged rod in the embodiment 1 of the present application is shown in the figure. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be described clearly and completely below, obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all the other embodiments obtained by the person skilled in the art without creative labor are within the protection scope of the present application.

[0041] The preparation method of the ingot provided by the present application comprises the following steps:

[0042] Step 1, the weighed C, Mn, Si, Ti, Nb, Cr, Cu and Fe are added into an induction crucible, and are smelted at 1490-1500 DEG C, the composition of the molten steel is tested, and the components are finely adjusted to C: 0.05-0.1%, Si: 0.2-0.4%, Ti: 0.3-0.5%, Nb: 1-2%, Cr: 25-31% and Cu: 0.1-0.31%, to obtain a first molten steel;

[0043] Step 2, under the condition of 1500-1520 DEG C and vacuum degree ≤2Pa, Al is added to the first molten steel, and is refined for more than 1.5h, the composition of the molten steel is tested, and the components are adjusted to C: 0.05-0.1%, Al: 3-4%, Si: 0.2-0.4%, Ti: 0.3-0.5%, Nb: 1-2%, Cr: 25-31%, Cu: 0.1-0.31%, S: 0.0003-0.001%, Fe: 4.0-5.3%, to obtain a second molten steel;

[0044] Step 3, argon is injected into the second molten steel, the pressure of the argon is controlled to be greater than or equal to 6000Pa, then Mn is added and stirred for 5-10min, the temperature of the molten steel is controlled to be 1430-1450 DEG C, and then the molten steel is poured into two Φ250mm electrodes;

[0045] Step 4, the mold cooling time of the control electrode is greater than 40 min, the mold is cooled to 700-800 DEG C, and after the mold cooling, the electrode is cover-cooled until the temperature is less than 150 DEG C, and the cover-cooling time is greater than 24 h;

[0046] Step 5, the surfaces of the two electrodes obtained in step 4 are polished by using a non-atmosphere protection electroslag furnace, and then electroslag remelting treatment is carried out, the furnace cooling time after power-off is greater than or equal to 60 min, and after demolding, air cooling is carried out to obtain the ingot;

[0047] The slag material comprises the following components in mass percentage: CaF2: 60%, Al2O3: 20%, CaO: 10%, and MgO: 10%;

[0048] The electroslag remelting parameters are as follows: the voltage is 56-65 V, the current is 6500-8000 A, the slag making time is 40-50 min, and the feeding time is 35-50 min.

[0049] The preparation method of the ingot provided by the application can be prepared by referring to the above method, but is not limited to the above preparation method.

[0050] Example 1

[0051] The nickel-based alloy forged rod provided by the embodiment comprises the following chemical components in mass percentage: C: 0.1%, Mn: 0.2%, Al: 4%, Si: 0.2%, Ti: 0.5%, Nb: 2%, Cr: 25%, Cu: 0.31%, S: 0.001%, Fe: 4.0%, and the balance is Ni and inevitable impurities.

[0052] The preparation method of the above nickel-based alloy forged rod comprises the following steps:

[0053] S1, the Φ480 mm ingot is pretreated, specifically including: the ingot to be treated is heated to 1150 DEG C and kept for 3 h, after the keeping, the ingot with a handle is obtained after pressure handle processing, the ingot is kept at 1120 DEG C for 2 h, the ingot after the keeping is upset forged and drawn, the upsetting ratio is 1.45, the drawing ratio is 2.1, and the first processed ingot with a square cross section is obtained;

[0054] S2, the first processed ingot is kept at 1130 DEG C for 2 h, the ingot after the keeping is drawn, the drawing ratio is 1.66, and the second processed ingot with a square cross section is obtained;

[0055] S3, the second processing ingot is kept at 1090 DEG C for 1h, the ingot after the keeping is wrapped with 5mm ceramic fiber, elongation forging is carried out, the elongation ratio is 1.94, air cooling is carried out, then the ingot is kept at 1050 DEG C for 60min, water cooling is carried out, the ingot is kept at 800 DEG C for 380min, air cooling is carried out, a nickel-based alloy forged bar is obtained.

[0056] Embodiment 2

[0057] The embodiment provides a nickel-based alloy forged bar which is composed of the following chemical components in percentage by mass: C: 0.05%, Mn: 0.5%, Al: 3%, Si: 0.4%, Ti: 0.3%, Nb: 1%, Cr: 31%, Cu: 0.1%, S: 0.0006%, Fe: 5.3%, and the balance of Ni and inevitable impurities.

[0058] The embodiment provides a preparation method of the nickel-based alloy forged bar.

[0059] S1, a Φ500mm ingot is pretreated, specifically including the following steps: the ingot to be treated is heated to 1150 DEG C and kept for 5h, after the keeping, the ingot is subjected to press jaw handle processing, a tail part ingot with a jaw handle is obtained, the ingot is kept at 1150 DEG C for 1h, the ingot after the keeping is subjected to upsetting forging and elongation forging, the upsetting ratio is 1.55, the elongation ratio is 1.89, a first processing ingot with a square cross section is obtained;

[0060] S2, the first processing ingot is kept at 1110 DEG C for 1h, the ingot after the keeping is subjected to elongation forging, the elongation ratio is 1.9, a second processing ingot with a square cross section is obtained;

[0061] S3, the second processing ingot is kept at 1120 DEG C for 1.5h, the ingot after the keeping is wrapped with 10mm ceramic fiber, elongation forging is carried out, the elongation ratio is 2, air cooling is carried out, then the ingot is kept at 1150 DEG C for 90min, water cooling is carried out, the ingot is kept at 810 DEG C for 360min, air cooling is carried out, a nickel-based alloy forged bar is obtained.

[0062] Embodiment 3

[0063] The embodiment provides a nickel-based alloy forged bar which is composed of the following chemical components in percentage by mass: C: 0.07%, Mn: 0.4%, Al: 3.5%, Si: 0.3%, Ti: 0.3%, Nb: 1.5%, Cr: 27%, Cu: 0.2%, S: 0.0007%, Fe: 5%, and the balance of Ni and inevitable impurities.

[0064] The embodiment provides a preparation method of the nickel-based alloy forged bar.

[0065] S1, the Φ500mm ingot is pretreated, specifically including: the ingot to be treated is heated to 1150℃ and kept for 4h, after keeping, the ingot with a tail handle is obtained after pressing handle processing, the ingot is kept at 1140℃ for 1h, upsetting forging and elongating forging are carried out on the ingot after keeping, wherein the upsetting ratio is 1.5, the elongating ratio is 2, and the first processed ingot with a square cross section is obtained;

[0066] S2, the first processed ingot is kept at 1120℃ for 1.5h, elongating forging is carried out on the ingot after keeping, the elongating ratio is 1.8, and the second processed ingot with a square cross section is obtained;

[0067] S3, the second processed ingot is kept at 1100℃ for 1h, the ingot after keeping is wrapped with 7mm ceramic fiber, elongating forging is carried out, the elongating ratio is 2, air cooling is carried out, then the ingot is kept at 1100℃ for 80min, water cooling is carried out, keeping at 800℃ for 370min, and air cooling is carried out, and the nickel-based alloy forged bar is obtained.

[0068] Example 4

[0069] Compared with example 1, the difference of the embodiment is that in S3, the elongating ratio is 2.2, and the embodiment is as follows:

[0070] The nickel-based alloy forged bar consists of the following chemical components in mass percentage: C: 0.1%, Mn: 0.2%, Al: 4%, Si: 0.2%, Ti: 0.5%, Nb: 2%, Cr: 25%, Cu: 0.31%, S: 0.001%, Fe: 4.0%, and the balance is Ni and inevitable impurities.

[0071] The embodiment provides a preparation method of the above-mentioned nickel-based alloy forged bar, which comprises the following steps:

[0072] S1, the Φ480mm ingot is pretreated, specifically including: the ingot to be treated is heated to 1150℃ and kept for 3h, after keeping, the ingot with a tail handle is obtained after pressing handle processing, the ingot is kept at 1120℃ for 2h, upsetting forging and elongating forging are carried out on the ingot after keeping, wherein the upsetting ratio is 1.45, the elongating ratio is 2.1, and the first processed ingot with a square cross section is obtained;

[0073] S2, the first processed ingot is kept at 1130℃ for 2h, elongating forging is carried out on the ingot after keeping, the elongating ratio is 1.66, and the second processed ingot with a square cross section is obtained;

[0074] S3, the second processing ingot is kept at 1090 °C for 1 h, the ingot after the keeping is wrapped with 5 mm ceramic fiber, elongation forging is carried out with an elongation ratio of 2.2, air cooling is carried out, then the ingot is kept at 1050 °C for 60 min, water cooling is carried out, the ingot is kept at 800 °C for 380 min, air cooling is carried out, and a nickel-based alloy forged bar is obtained.

[0075] Comparative Example 1

[0076] The present comparative example provides a nickel-based alloy forged bar, which is different from Example 1 in that Cu is replaced with an equal amount of Ni, and other components remain unchanged; specifically comprising the following:

[0077] The nickel-based alloy forged bar consists of the following chemical components in mass percentage: C: 0.1%, Mn: 0.2%, Al: 4%, Si: 0.2%, Ti: 0.5%, Nb: 2%, Cr: 25%, S: 0.001%, Fe: 4.0%, and the balance of Ni and unavoidable impurities.

[0078] The nickel-based alloy forged bar specifically comprises the following steps:

[0079] S1, the ingot with a diameter of 480 mm is pretreated, specifically comprising: the ingot to be treated is heated to 1150 °C and kept for 3 h, after the keeping, the ingot with a tail handle is obtained after pressing handle processing, the ingot is kept at 1120 °C for 2 h, the ingot after the keeping is subjected to upsetting forging and elongation forging, wherein the upsetting ratio is 1.45 and the elongation ratio is 2.1, and a first processing ingot with a square cross section is obtained;

[0080] S2, the first processing ingot is kept at 1130 °C for 2 h, the ingot after the keeping is subjected to elongation forging with an elongation ratio of 1.66, and a second processing ingot with a square cross section is obtained;

[0081] S3, the second processing ingot is kept at 1090 °C for 1 h, the ingot after the keeping is wrapped with 5 mm ceramic fiber, elongation forging is carried out with an elongation ratio of 1.94, air cooling is carried out, then the ingot is kept at 1050 °C for 60 min, water cooling is carried out, the ingot is kept at 800 °C for 380 min, air cooling is carried out, and a nickel-based alloy forged bar is obtained.

[0082] Comparative Example 2

[0083] The present comparative example provides a nickel-based alloy forged bar, which is different from Example 1 in that Mn is replaced with an equal amount of Ni, and other components remain unchanged; specifically comprising the following:

[0084] The nickel-based alloy forged bar is composed of the following chemical components: C: 0.1%, Al: 4%, Si: 0.2%, Ti: 0.5%, Nb: 2%, Cr: 25%, Cu: 0.31%, S: 0.001%, Fe: 4.0%, and the balance of Ni and inevitable impurities.

[0085] The preparation method of the nickel-based alloy forged bar comprises the following steps:

[0086] S1, the cast ingot of Φ480mm is pretreated, specifically including: the cast ingot to be treated is heated to 1150℃ and kept for 3h, after the keeping, the cast ingot with a handle at the tail is obtained after the pressing handle treatment, the cast ingot is kept at 1120℃ for 2h, the upsetting forging and the elongation forging are performed on the cast ingot after the keeping, the upsetting ratio is 1.45, the elongation ratio is 2.1, and the first treated cast ingot with a square cross section is obtained;

[0087] S2, the first treated cast ingot is kept at 1130℃ for 2h, the elongation forging is performed on the cast ingot after the keeping, the elongation ratio is 1.66, and the second treated cast ingot with a square cross section is obtained;

[0088] S3, the second treated cast ingot is kept at 1090℃ for 1h, the elongation forging is performed on the cast ingot after the keeping, the elongation ratio is 1.94, the air cooling is performed, then the cast ingot is kept at 1050℃ for 60min, the water cooling is performed, the cast ingot is kept at 800℃ for 380min, and the air cooling is performed, and the nickel-based alloy forged bar is obtained.

[0089] Comparative Example 3

[0090] The comparative example provides a nickel-based alloy forged bar, which is different from the example 1 in that only the upsetting forging is performed in S1, the elongation forging is not performed, and the other components and steps are unchanged; specifically including the following:

[0091] The preparation method of the nickel-based alloy forged bar comprises the following steps:

[0092] S1, the cast ingot of Φ480mm is pretreated, specifically including: the cast ingot to be treated is heated to 1150℃ and kept for 3h, after the keeping, the cast ingot with a handle at the tail is obtained after the pressing handle treatment, the cast ingot is kept at 1120℃ for 2h, the upsetting forging is performed on the cast ingot after the keeping, the upsetting ratio is 1.45, and the first treated cast ingot with a square cross section is obtained;

[0093] S2, the first treated cast ingot is kept at 1130℃ for 2h, the elongation forging is performed on the cast ingot after the keeping, the elongation ratio is 1.66, and the second treated cast ingot with a square cross section is obtained;

[0094] S3, the second processing ingot is kept at 1090 DEG C for 1 h, the ingot after the keeping is wrapped with 5 mm ceramic fiber, elongation forging is carried out, the elongation ratio is 1.94, air cooling is carried out, then the ingot is kept at 1050 DEG C for 60 min, water cooling is carried out, the ingot is kept at 800 DEG C for 380 min, air cooling is carried out, and a nickel-based alloy forged bar is obtained.

[0095] Comparative Example 4

[0096] The present comparative example provides a nickel-based alloy forged bar, which is different from example 1 in that in S2, the temperature of keeping is increased, and other components and steps are unchanged; specifically comprising the following:

[0097] The preparation method of the nickel-based alloy forged bar comprises the following steps:

[0098] S1, the ingot with a diameter of 480 mm is pretreated, specifically comprising: the ingot to be treated is heated to 1150 DEG C and kept for 3 h, after the keeping, the ingot is subjected to press handle processing, and the ingot with a handle at the tail is obtained, the ingot is kept at 1120 DEG C for 2 h, the ingot after the keeping is subjected to upsetting forging and elongation forging, the upsetting ratio is 1.45, the elongation ratio is 2.1, and a first processing ingot with a square cross section is obtained;

[0099] S2, the first processing ingot is kept at 1180 DEG C for 2 h, the ingot after the keeping is subjected to elongation forging, and the elongation ratio is 1.66, so that a second processing ingot with a square cross section is obtained;

[0100] S3, the second processing ingot is kept at 1090 DEG C for 1 h, the ingot after the keeping is wrapped with 5 mm ceramic fiber, elongation forging is carried out, the elongation ratio is 1.94, air cooling is carried out, then the ingot is kept at 1050 DEG C for 60 min, water cooling is carried out, the ingot is kept at 800 DEG C for 380 min, air cooling is carried out, and a nickel-based alloy forged bar is obtained.

[0101] Comparative Example 5

[0102] The present comparative example provides a nickel-based alloy forged bar, which is different from example 1 in that the S3 step is omitted, and other components and steps are unchanged; specifically comprising the following:

[0103] The preparation method of the nickel-based alloy forged bar comprises the following steps:

[0104] S1, the ingot with a diameter of 480 mm is pretreated, specifically comprising: the ingot to be treated is heated to 1150 DEG C and kept for 3 h, after the keeping, the ingot is subjected to press handle processing, and the ingot with a handle at the tail is obtained, the ingot is kept at 1120 DEG C for 2 h, the ingot after the keeping is subjected to upsetting forging and elongation forging, the upsetting ratio is 1.45, the elongation ratio is 2.1, and a first processing ingot with a square cross section is obtained;

[0105] S2, the first processing ingot is kept at 1130 DEG C for 2h, the ingot after the keeping is wrapped with 5mm ceramic fiber, elongation forging is carried out, the elongation ratio is 1.66, air cooling is carried out, then the ingot is kept at 1050 DEG C for 60min, water cooling is carried out, the ingot is kept at 800 DEG C for 380min, air cooling is carried out, and a nickel-based alloy forged bar is obtained.

[0106] Effect example

[0107] In order to further embody the technical effect of the present application, the bar obtained in examples 1-4 and the bar obtained in comparative examples 1-5 are subjected to the following performance test.

[0108] The yield strength, tensile strength, elongation and reduction of area are detected according to the standard of ASTM E8 / E8M-24, and the results are shown in Table 1.

[0109] Table 1: performance test results of each bar

[0110]

[0111] The nickel-based alloy forged bar provided by the embodiment of the present application has excellent strength and plasticity, and the forging process does not crack. The tensile strength can reach 1117MPa, the elongation can reach 60%, and the reduction of area can reach 58%.

[0112] The above only describes the preferred embodiments of the present application and is not used to limit the present application, and any modification, equivalent replacement or improvement made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A nickel-based alloy forging bar, characterized in that: Calculated in mass percentage, the chemical components include the following mass percentages: C: 0.05%~0.1%, Mn: 0.2%~0.5%, Al: 3%~4%, Si: 0.2%~0.4%, Ti: 0.3%~0.5%, Nb: 1%~2%, Cr: 25%~31%, Cu: 0.1%~0.31%, S: 0.0003%~0.001%, Fe: 4.0%~5.3%, and the balance is Ni and unavoidable impurities.

2. A method for preparing the nickel-based alloy forging bar according to claim 1, characterized in that: The steps include: S1, keeping the ingot at 1120° C. to 1150° C., and performing upsetting forging and stretching forging on the ingot after the holding is completed to obtain a first treated ingot; S2, keeping the first treated ingot at 1110° C. to 1130° C., and performing stretching forging on the ingot after the holding is completed to obtain a second treated ingot; S3. The second-treated ingot is kept at 1090° C. to 1120° C., the ingot is wrapped with ceramic fiber, and then stretched and forged, air-cooled, and heat-treated to obtain a nickel-based alloy forged rod.

3. The method for preparing the nickel-based alloy forging bar according to claim 2, wherein: In S1, the diameter of the ingot is 480 mm to 500 mm.

4. The method for preparing the nickel-based alloy forging bar according to claim 2, wherein: In S1, the insulation time is 1 h to 2 h.

5. The method for preparing the nickel-based alloy forging bar according to claim 2, wherein: In S1, the upsetting ratio of the upsetting forging is 1.45 to 1.55; and / or In S1, the drawing ratio of the drawing forging is 1.89 to 2.

1.

6. The method for preparing the nickel-based alloy forging bar according to claim 2, wherein: In S2, the insulation time is 1 hour to 2 hours.

7. The method for preparing nickel-based alloy forging bar according to claim 2, wherein: In S2, the drawing ratio of the drawing forging is 1.66 to 1.

9.

8. The method for preparing nickel-based alloy forging bar according to claim 2, wherein: In S3, the insulation time is 1 hour to 1.5 hours.

9. The method for preparing a nickel-based alloy forging bar according to claim 2, wherein: In S3, the drawing ratio of the drawing forging is 1.94-2.

10. The method for preparing nickel-based alloy forging bar according to claim 2, wherein: In S3, the coating thickness of the ceramic fiber is 5 mm to 10 mm; and / or In S3, the heat treatment conditions are: keeping at 1050°C to 1150°C and then cooling with water, and then keeping at 800°C to 810°C and then cooling with air.

Images