Printable Gamma Prime Super Alloy

Abstract

Nickel-based alloy composition for additive manufacturing and additive-manufactured parts made from nickel-based alloy, comprising 36-89 wt% nickel, 4-9 wt% aluminum, 6-14 wt% cobalt, 4-26 wt% chromium, 2-5 wt% tantalum, and 3-13 wt% tungsten. The nickel-based alloy composition has a crack density of 4.0 cracks / mm². 2 To provide additive manufacturing parts having a crack density of less than 1.

Description

[Technical Field]

[0001] (Cross-reference of related applications) This application claims the interests of U.S. Provisional Application No. 63 / 461,667, filed on 25 April 2023, the disclosures of which are expressly incorporated herein by reference in their entirety.

[0002] (Field of invention) The embodiments relate to Ni-based alloys used in additive manufacturing (AM) of net-shape or near-net-shape parts for aerospace, power generation, automotive, or general industrial applications, but not limited to these. [Background technology]

[0003] Gamma-prime reinforced superalloys are important materials used in the manufacture of components exposed to high temperatures in gas turbine engines. They generally exhibit high mechanical strength, creep resistance, corrosion resistance, and oxidation resistance at high temperatures. Gamma-prime precipitates are crucial in achieving these unique properties.

[0004] Historically, superalloy design has centered around conventional manufacturing processes such as casting or forging. However, with advancements in additive manufacturing (AM) capabilities, there is growing interest in using AM to produce gamma-prime reinforced superalloy components. In this regard, AM offers advantages over conventional manufacturing processes, such as increased design freedom for components and reduced material waste.

[0005] A key requirement for successful AM (additive manufacturing) of superalloys is the ability to print crack-free parts. It has been observed that cracking increases with increasing gamma-prime phase fraction, which makes successful AM processing of high-gamma-prime superalloys more difficult.

[0006] Cracks or any defects in AM parts significantly degrade the mechanical properties and performance of the parts. As a result, if these AM parts fail to achieve the required performance, the advantages of AM over conventional manufacturing techniques are lost.

[0007] While known prior art provides special manufacturing techniques for gamma-prime superalloys with a wide composition range, these composition ranges do not teach the techniques disclosed herein in that they include both cracking and non-cracking superalloy compositions when applied by additive manufacturing processes. In fact, the majority of potential alloys within these broad composition ranges will crack when applied via additive manufacturing processes. For example, U.S. Patent No. 4,226,644 describes the manufacture of superalloy parts by particulate matter compression techniques, which are thought to be related to a wide composition range. However, the majority of alloys within the disclosed composition range will crack when processed by additive manufacturing. Furthermore, U.S. Patent Application Publication No. 2020 / 0010930(A1) describes the manufacture of superalloy parts by hot plastic working techniques, which are thought to be related to a wide composition range. In this case as well, the majority of alloys within the composition range will crack when processed by additive manufacturing.

[0008] Gamma-prime-reinforced nickel-based superheat-resistant alloys (AMs) are known, for example, from European Patent No. 2886225(B1), European Patent No. 2949768(B1), U.S. Patent No. 10,941,466(B2), U.S. Patent No. 10,752,978(B2), U.S. Patent Publication No. 2021 / 0355564(A1), U.S. Patent Publication No. 2020 / 0172998(A1), and U.S. Patent Publication No. 2020 / 0149145(A1). However, these alloys contain components in amounts outside the range described in the disclosed embodiments, and similarly, lead to unacceptable cracking in AM parts. Furthermore, other gamma-prime-reinforced nickel-based superalloys are known, for example, from U.S. Patent No. 5,069,873, U.S. Patent No. 9,902,021 (B2), U.S. Patent No. 1,035,8701 (B2), U.S. Patent No. 1,145,9640 (B2), U.S. Patent No. 2019,005,5627 (A1), and International Publication No. 2018,157,228 (A1), but these alloys also contain components in amounts outside the range described in the disclosed embodiments, resulting in unacceptable cracking in AM parts. [Overview of the project]

[0009] The embodiment aims to improve the manufacturability of high-gamma-prime superalloys by reducing crack susceptibility during AM treatment.

[0010] The embodiments relate to nickel-based alloy compositions for additive manufacturing, comprising 4-9 wt% aluminum, 6-14 wt% cobalt, 4-26 wt% chromium, 2-5 wt% tantalum, 3-13 wt% tungsten, and the remainder nickel.

[0011] According to the embodiment, the nickel-based alloy composition may further include at least one of up to 8 wt% molybdenum, up to 1 wt% titanium, and up to 4 wt% niobium.

[0012] In other embodiments, the aluminum composition may be 4.5–7.7 wt%, the cobalt composition may be 7.7–12.9 wt%, the chromium composition may be 5–23 wt%, the tantalum composition may be 2.5–4.8 wt%, and the tungsten composition may be 3.3–11 wt%. The nickel-based alloy composition may further include at least one of up to 7.0 wt% molybdenum, up to 0.9 wt% titanium, and up to 2.8 wt% niobium. In other embodiments, the aluminum composition may be 5–7 wt%, the cobalt composition may be 8–12 wt%, the chromium composition may be 5–23 wt%, the tantalum composition may be 3–4 wt%, and the tungsten composition may be 4–11 wt%. The nickel-based alloy composition may further include at least one of up to 7 wt% molybdenum, up to 1 wt% titanium, and up to 3 wt% niobium.

[0013] In yet another embodiment, the additively manufactured part may include the nickel-based alloy composition specified above. The part may have a high-temperature crack index of less than 2.0, a shale porridge zone of less than 250K, an equilibrium porridge zone of less than 100K, a gamma-prime phase fraction of 40-67 mol% at 1200K, a gamma-prime formation temperature of less than 1500K, a topologically close-packed (TCP) formation temperature of 900K-1650K, and a density of 1.50 mm / mm 2 Crack density less than 350 HV 0.3 ~560 HV 0.3 It may include at least one of the hardnesses.

[0014] According to the embodiment, the nickel-based alloy composition may more specifically include Al: 3.9-7.2 wt%, Co: 6.4-12.0 wt%, Cr: 14.0-26.0 wt%, Mo: 0.4-0.7 wt%, Ta: 2.2-4.0 wt%, Ti: 0.5-0.9 wt%, W: 6.7-12.4 wt%, and Ni: the remainder. Furthermore, the aluminum composition may be 4.7-6.3 wt%, the cobalt composition may be 7.8-10.6 wt%, the chromium composition may be 17.0-23.0 wt%, the molybdenum composition may be 0.4-0.6 wt%, the tantalum composition may be 2.6-3.6 wt%, the titanium composition may be 0.6-0.8 wt%, and the tungsten composition may be 8.1-10.9 wt%. The additively manufactured parts contain the above nickel-based alloy composition, with a thickness of 0.09 mm / mm². 2 It can have a crack density of [value missing]. Furthermore, this part can exhibit a high-temperature crack index of 0.58.

[0015] According to other embodiments, the nickel-based alloy composition may more specifically include Al: 3.9-7.2 wt%, Co: 6.4-12.0 wt%, Cr: 5.7-10.7 wt%, Mo: 4.2-7.8 wt%, Ta: 2.2-4.0 wt%, Ti: 0.5-0.9 wt%, W: 6.7-12.4 wt%, and Ni: the remainder. Furthermore, the aluminum composition may be 4.7-6.3 wt%, the cobalt composition may be 7.8-10.6 wt%, the chromium composition may be 7.0-9.4 wt%, the molybdenum composition may be 5.1-6.9 wt%, the tantalum composition may be 2.6-3.6 wt%, the titanium composition may be 0.6-0.8 wt%, and the tungsten composition may be 8.1-10.9 wt%. The additively manufactured parts contain the above nickel-based alloy composition, with a thickness of 0.12 mm / mm². 2 It can have a crack density of [value]. Furthermore, this part can exhibit a high-temperature crack index of 0.50.

[0016] In other embodiments, the nickel-based alloy composition may include, in particular, Al: 3.9-7.2 wt%, Co: 6.4-12.0 wt%, Cr: 5.7-10.7 wt%, Mo: 0.4-0.7 wt%, Nb: 1.5-2.9 wt%, Ta: 2.2-4.0 wt%, W: 2.8-5.2 wt%, and Ni: the remainder. Furthermore, the aluminum composition may be 4.7-6.3 wt%, the cobalt composition may be 7.8-10.6 wt%, the chromium composition may be 7.0-9.4 wt%, the molybdenum composition may be 0.4-0.6 wt%, the niobium composition may be 1.9-2.5 wt%, and the tantalum composition may be 2.6-3.6 wt%, and the tungsten composition may be 3.4-4.6 wt%. The additively manufactured parts contain the above nickel-based alloy composition, 1.31 mm / mm 2 It can have a crack density of [value]. Furthermore, this part can exhibit a high-temperature crack index of 1.76.

[0017] In further embodiments, the nickel-based alloy composition may include Al: 3.9-7.2 wt%, Co: 6.4-12.0 wt%, Cr: 7.1-13.3 wt%, Mo: 0.4-0.7 wt%, Ta: 2.2-4.0 wt%, Ti: 0.5-0.9 wt%, W: 5.3-9.8 wt%, and Ni: the remainder. Furthermore, the aluminum composition may be 4.7-6.3 wt%, the cobalt composition may be 7.8-10.6 wt%, the chromium composition may be 8.7-11.7 wt%, the molybdenum composition may be 0.4-0.6 wt%, the tantalum composition may be 2.6-3.6 wt%, the titanium composition may be 0.6-0.8 wt%, and the tungsten composition may be 6.4-8.6 wt%. The additively manufactured parts contain the above nickel-based alloy composition, with a thickness of 1.37 mm / mm². 2 It can have a crack density of [value]. Furthermore, this part can exhibit a high-temperature crack index of 1.24.

[0018] According to still other embodiments, the nickel-based alloy composition may include Al: 4.6 to 8.5 wt%, Co: 7.7 to 14.3 wt%, Cr: 4.2 to 7.8 wt%, Ta: 2.2 to 4.0 wt%, W: 5.6 to 10.4 wt%, and the balance Ni. Further, the composition of aluminum may be 5.5 to 7.5 wt%. The composition of cobalt may be 9.4 to 12.7 wt%. The composition of chromium may be 5.1 to 6.9 wt%. The composition of tantalum may be 2.6 to 3.6 wt%. The composition of tungsten may be 6.8 to 9.2 wt%. The additive manufactured part may include the above nickel-based alloy composition and have a crack density of 1.44 mm / mm 2 and may exhibit a hot crack index of 0.95.

[0019] According to still other embodiments, the nickel-based alloy composition may include Al: 4.6 to 8.5 wt%, Co: 7.0 to 13.0 wt%, Cr: 5.6 to 10.4 wt%, Ta: 2.8 to 5.2 wt%, W: 4.2 to 7.8 wt%, and the balance Ni. Further, the composition of aluminum may be 5.5 to 7.5 wt%. The composition of cobalt may be 8.5 to 11.5 wt%. The composition of chromium may be 6.8 to 9.2 wt%. The composition of tantalum may be 3.4 to 4.6 wt%. The composition of tungsten may be 5.1 to 6.9 wt%. The additive manufactured part may include the above nickel-based alloy composition and have a crack density of 1.46 mm / mm 2 and may exhibit a hot crack index of 0.88.

[0020] The embodiments are directed to additive manufactured parts that include a nickel-based alloy composition and have a hot crack index of less than 2.0, a shale mush zone of less than 250 K, an equilibrium mush zone of less than 100 K, a gamma prime phase fraction at 1200 K of 40 to 65 mol%, a gamma prime formation temperature of less than 1500 K, and a TCP formation temperature of 900 K to 1600 K.

[0021] The embodiments include a nickel-based alloy composition and have a crack density of less than 1.50 mm / mm 2 and a hardness of 350 HV 0.3This applies to additively manufactured parts with a hardness of up to 560. [Brief explanation of the drawing]

[0022] The present invention is further described in the following detailed description with reference to several drawings which are cited as non-limiting examples of exemplary embodiments of the invention, and similar reference numerals throughout some of the drawings represent similar parts. [Figure 1] A graph shows a Shale-Gulliver model based on the solidification behavior of the alloy for calculating the high-temperature crack index (HCI) for the embodiment. [Figure 2] The Shale-Gulliver model for determining the alloy porridge zone in the embodiment is shown graphically. [Figure 3] In an exemplary embodiment, the equilibrium calculation, particularly highlighting the gamma prime fraction and the equilibrium porridge zone, is shown graphically. [Figure 4] For exemplary embodiments, equilibrium calculations that specifically highlight the gamma prime formation temperature and the first TCP phase are shown graphically. [Figure 5] This shows cracks in the printed microstructure of a known gamma-prime superalloy. [Modes for carrying out the invention]

[0023] The details provided herein are illustrative and intended solely for illustrative purposes of embodiments of the present invention, and are presented to provide what is considered to be the most useful and readily understandable explanation of the principles and conceptual aspects of the present invention. In this regard, no attempt has been made to provide structural details of the present invention in more detail than is necessary for a basic understanding of the present invention, and the description provided in conjunction with the drawings will make it clear to those skilled in the art how some forms of the present invention can actually be embodied.

[0024] As used herein, the singular forms “a,” “an,” and “the” include multiple references unless the context explicitly indicates otherwise. For example, a reference to “a powder material” further implies that a mixture of one or more powder materials may exist, unless specifically excluded. As used herein, the indefinite article “a” indicates one or more and does not necessarily limit its referent noun to the singular form.

[0025] Unless otherwise indicated, all numbers representing quantities used herein and in the claims should be understood to be modified in all embodiments by the term "about." Therefore, unless otherwise indicated, the numerical parameters described herein and in the claims are approximations that may vary depending on the desired characteristics sought by the embodiments of this disclosure. Each numerical parameter should be interpreted in light of the number of significant figures and the usual methods of rounding off decimal places, and should not be considered as an attempt to limit the application of the doctrine of equivalents to the claims.

[0026] Furthermore, any enumeration of numerical ranges within this specification is considered to be a disclosure of all numbers and ranges within that range (unless otherwise explicitly indicated). For example, if the range is approximately 1 to approximately 40, it is considered to include, for example, 1, 7, 23.7, 34, 36.1, 40, or any other value or range within that range.

[0027] Where used herein, the terms “about” and “approximately” indicate that the quantity or value in question may be a specific value or some other value in its vicinity. Generally, the terms “about” and “approximately” indicating a specific value are intended to indicate a range of ±5% of that value. In one embodiment, the phrase “about 100” indicates a range of 100 ± 5, i.e., 95 to 105. Generally, where the terms “about” and “approximately” are used, it can be expected that similar results or effects according to this disclosure can be obtained within a range of ±5% of the indicated value.

[0028] The term "at least partially" is intended to indicate that the following characteristics are met to some extent (e.g., 25% or 50%) or completely:

[0029] The terms “substantially” and “essentially” are used to indicate that the following features, characteristics, or parameters are either fully realized or satisfied (overall), or to a major degree (such as 90%, 95%, or 99%) that does not adversely affect the intended outcome.

[0030] The term “comprising” as used herein is intended to be non-exclusive and open-ended. Therefore, for example, a composition comprising oxide A may also comprise other oxides. However, the term “comprising” further encompasses the more restrictive meanings of “consisting essentially of” and “consisting of,” so that, for example, “a composition comprising oxide A” may also consist (essentially) of oxide A.

[0031] In this disclosure, unless otherwise specified, all weight percentages relating to elements / components of a composition / material / layer are based on the total weight of the composition / material / layer including any unavoidable impurities that may be present.

[0032] The alloy composition according to the embodiment provides a high-gamma-prime superalloy with improved manufacturability by reducing the crack susceptibility of the alloy in additive manufacturing (AM) processes. This alloy composition contains nickel as the primary element and may further contain aluminum, cobalt, chromium, molybdenum, niobium, tantalum, titanium, and tungsten. In a preferred embodiment, the alloy composition may contain about 4–9 wt% aluminum, 6–14 wt% cobalt, 4–26 wt% chromium, 2–5 wt% tantalum, 3–13 wt% tungsten, and the remainder nickel. Furthermore, this alloy composition may (optionally) contain at least one of up to 8 wt% molybdenum, up to 4 wt% niobium, and / or up to 1 wt% titanium. Furthermore, if the alloy composition contains niobium, it may be advantageous to contain only up to 1.0 wt%, preferably up to 0.5 wt%, of niobium.

[0033] In a more preferred embodiment, the alloy composition may include about 5–7 wt% aluminum, 8–12 wt% cobalt, 5–23 wt% chromium, 3–4 wt% tantalum, and 4–11 wt% tungsten. Furthermore, this preferred embodiment of the alloy composition may (optionally) include at least one of up to 7 wt% molybdenum, up to 3 wt% niobium, and / or up to 1 wt% titanium. Furthermore, if the alloy composition contains niobium, it may be advantageous to include only up to 1.0 wt%, preferably 0.5 wt% of niobium. [Examples]

[0034] Example 1 (X2): The alloy composition is, Al: 3.9-7.2% by weight, preferably 4.7-6.3% by weight. Co: 6.4-12.0% by weight, preferably 7.8-10.6% by weight. Cr: 14.0-26.0% by weight, preferably 17.0-23.0% by weight. Mo: 0.4-0.7% by weight, preferably 0.4-0.6% by weight. Ta: 2.2-4.0% by weight, preferably 2.6-3.6% by weight. Ti: 0.5-0.9% by weight, preferably 0.6-0.8% by weight. W: 6.7-12.4% by weight, preferably 8.1-10.9% by weight. Ni: Includes the remaining portion.

[0035] Example 2 (X3): Al: 3.9-7.2% by weight, preferably 4.7-6.3% by weight. Co: 6.4-12.0% by weight, preferably 7.8-10.6% by weight. Cr: 5.7~10.7% by weight, preferably 7.0~9.4% by weight. Mo: 4.2-7.8% by weight, preferably 5.1-6.9% by weight. Ta: 2.2-4.0% by weight, preferably 2.6-3.6% by weight. Ti: 0.5-0.9% by weight, preferably 0.6-0.8% by weight. W: 6.7-12.4% by weight, preferably 8.1-10.9% by weight, and Ni: Rest.

[0036] Example 3 (X4): Al: 3.9-7.2% by weight, preferably 4.7-6.3% by weight. Co: 6.4-12.0% by weight, preferably 7.8-10.6% by weight. Cr: 5.7~10.7% by weight, preferably 7.0~9.4% by weight. Mo: 0.4-0.7% by weight, preferably 0.4-0.6% by weight. Nb: 1.5-2.9% by weight, preferably 1.9-2.5% by weight. Ta: 2.2-4.0% by weight, preferably 2.6-3.6% by weight. W: 2.8-5.2% by weight, preferably 3.4-4.6% by weight, and Ni: Rest.

[0037] Example 4 (X5): Al: 3.9-7.2% by weight, preferably 4.7-6.3% by weight. Co: 6.4-12.0% by weight, preferably 7.8-10.6% by weight. Cr: 7.1-13.3% by weight, preferably 8.7-11.7% by weight. Mo: 0.4-0.7% by weight, preferably 0.4-0.6% by weight. Ta: 2.2-4.0% by weight, preferably 2.6-3.6% by weight. Ti: 0.5-0.9% by weight, preferably 0.6-0.8% by weight. W: 5.3-9.8% by weight, more preferably 6.4-8.6% by weight, and Ni: Rest.

[0038] Example 5 (X6): Al: 4.6-8.5% by weight, preferably 5.5-7.5% by weight. Co: 7.7-14.3% by weight, preferably 9.4-12.7% by weight. Cr: 4.2-7.8% by weight, preferably 5.1-6.9% by weight. Ta: 2.2-4.0% by weight, preferably 2.6-3.6% by weight. W: 5.6~10.4% by weight, more preferably 6.8~9.2% by weight, and Ni: remaining

[0039] Example 6 (X7): Al: 4.6-8.5% by weight, preferably 5.5-7.5% by weight. Co: 7.0-13.0% by weight, preferably 8.5-11.5% by weight. Cr: 5.6~10.4% by weight, preferably 6.8~9.2% by weight. Ta: 2.8-5.2% by weight, preferably 3.4-4.6% by weight. W: 4.2-7.8% by weight, more preferably 5.1-6.9% by weight, and Ni: Rest.

[0040] Furthermore, the exemplary compositions in this disclosure, including the experimental alloys X2-X7 described above, were formed by blending elemental powders to achieve the target compositions. However, since the experimental alloys are intended for use in additive manufacturing via gas atomization (GA), it may be advantageous to produce powder feedstocks. Gas atomization processes are known in the art, as disclosed in U.S. Patents No. 4,988,464 and 4,064,295, European Patent No. 0225080, and the paper "Metal Powder Atomization Methods for Modern Manufacturing" by J. Dunkley (these disclosures are expressly incorporated herein by reference in their entirety).

[0041] thermodynamic criteria In embodiments, the alloy may be described by its retained thermodynamic characteristics. This alloy exhibits a low High Temperature Crack Index (HCI), as defined by Clyne and Davis to predict high temperature crack susceptibility in cast alloys. The High Temperature Crack Index is calculated from the Shale-Gulliver model and is based on the solidification behavior of the alloy. The following formula is used to calculate the High Temperature Crack Index criterion.

[0042]

number

[0043] In addition to HCI, the Shale-Gulliver model can also be used to calculate the porridge zone of an alloy. The porridge zone criterion is defined as the temperature difference between the liquidus temperature and the solidus temperature. The liquidus temperature is defined as the temperature at which the first solid phase begins to form, and the solidus temperature is defined as the temperature at which the alloy is completely solidified. Similar to HCI, a lower porridge zone value can be an indicator of the alloy's tendency towards high-temperature cracking or solidification cracking. Furthermore, a low porridge zone is desirable to promote rapid solidification of the alloy and reduce compositional heterogeneity. In embodiments, the porridge zone is 250K or less, preferably 200K or less, and more preferably 150K or less. As an example, Figure 2 shows the Shale-Gulliver model for the alloy described in Example 2(X3), where the porridge zone is 116K.

[0044] Similar methods for calculating the porridge zone criterion can be applied to equilibrium calculations. As a non-limiting example, Figures 3 and 4 and Table 1 show the equilibrium calculation for Example 5(X6). When using equilibrium calculations, the same definitions described above for the Shale-Gulliver model are applied to the solidus and liquidus temperatures, and lower porridge zone values, called equilibrium porridge zone values, correspond to alloys with lower susceptibility to high-temperature cracks or solidification cracks. In some embodiments, the porridge zone is 100K or less. In preferred embodiments, the porridge zone is 75K or less. In even more preferred embodiments, the porridge zone is 50K or less.

[0045] Equilibrium calculations can also be used to predict the gamma-prime phase fraction in the alloy. Generally, for nickel-based superalloys intended for use in high-temperature and high-stress applications, a high gamma-prime fraction, e.g., over 30 mol% at 1200 K, is desirable. Conventionally, cast superalloys used in these types of applications tend to contain a gamma-prime fraction of over 50%. High-temperature aging heat treatment in the range of about 800-1000°C (1073-1273 K) is commonly used to precipitate the gamma-prime phase. However, these conventional cast superalloys cannot be printed without cracking by AM. From equilibrium calculations, the gamma-prime phase fraction at 1200 K is obtained (see Figure 3). In some embodiments, the gamma-prime fraction at 1200 K is 40-50 mol%, preferably 45-55 mol%, and more preferably 55-67 mol%.

[0046] The gamma-prime formation temperature is another important criterion for predicting the crack behavior of nickel-based superalloys treated by AM. Some gamma-prime may form during the solidification of the molten pool. Additional gamma-prime precipitation can also be induced by reheating the alloy during the application of subsequent layers. Gamma-prime formation and precipitation during AM treatment are more likely to occur in nickel-based superalloys designed to form a high percentage of gamma-prime. Gamma-prime precipitation reduces the ductility of the alloy, and as internal stresses increase from the heating and cooling cycles caused by the application of each building layer, cracks may develop. This phenomenon is often called strain-aging cracking. By evaluating the gamma-prime formation temperature using equilibrium calculations, as shown in Figure 4, the susceptibility of the alloy to strain-aging cracking is predicted. Lower gamma-prime formation temperatures, e.g., below 1500K, suggest less gamma-prime formation during the printing process and therefore a reduced tendency of the alloy to strain-aging crack. In the embodiment, the gamma prime formation temperature may be less than 1500K, preferably less than 1475K, and more preferably less than 1450K.

[0047] Similar to the formation temperature of the gamma prime, the formation temperature of the first phase close-packed (TCP) phase can also be predicted from equilibrium calculations. In embodiments, the first TCP phase formation temperature may be 900 to 1650 K, preferably 1100 to 1600 K, and more preferably 1300 to 1600 K. The TCP phase is known to include the A15 phase, the Raves phase, the sigma, mu, M, P, and R phases. Figure 4 shows the first TCP phase formation temperature of Example 5 (X6).

[0048] All thermodynamic properties of alloys produced by the AM treatment of exemplary embodiments of alloy powders are described above and listed in Table I. It is understood that the thermodynamic properties of each exemplary powder are the same regardless of the method by which the exemplary alloy powders are formed, including the spraying process. However, as described below, the performance properties of the alloy powders may vary depending on the powder composition and applied process parameters.

[0049] [Table 1]

[0050] Microstructure criteria The embodiments can be described by the microstructural features they possess. In the embodiments, the gamma-prime phase fraction in the microstructure may be greater than 40%, preferably greater than 50%, and more preferably greater than 60%. In the embodiments, the TCP phase fraction in the microstructure is less than 35%, preferably less than 25%, and more preferably less than 15%. In the embodiments, the crack density in the microstructure when treated by AM is 1.50 mm / mm 2 Less than 1.00 mm / mm 2 Less than, more preferably 0.50 mm / mm 2 It is less than.

[0051] performance standards The embodiments relate to alloys that exhibit increased crack resistance compared to conventional cast alloys when treated by AM. To fully utilize the advantages of AM, it is crucial to manufacture parts free from defects that would result in significant loss of mechanical properties and functionality. Defects can be quantified using a simple optical microstructure evaluation of the printed part. Figure 5 shows an example of cracks in the printed microstructure of a conventional nickel-based alloy such as CM247LC. The crack susceptibility of an alloy during AM treatment can be quantified by crack density, which can be done in two different ways: 1) by counting the total number of cracks present in a given cross-sectional area per 1 mm². 2 1) The unit of cracks per square meter, and 2) the sum of the lengths of all cracks present in a given cross-sectional area, in 1 mm². 2 The calculation can be performed in units of total crack length per unit area (mm). Measuring crack length per unit area (Method 2) is a more common method for measuring crack density in AM parts. Nickel-based alloys designed for conventional casting, such as CM247LC, when treated with AM, can have a crack density of, for example, 4.96 mm / mm. 2 It exhibits a high crack density. In contrast, the crack density of the as-printed alloy according to the disclosed embodiment is 1.50 mm / mm². 2 Less than 1.00 mm / mm 2 Less than, more preferably 0.50 mm / mm 2 It may be less than.

[0052] In addition to the conventional alloy CM247LC, the experimental alloys X2-X7 described above were printed using a powder-feed direct energy deposition (DED) machine equipped with a 650 W AO-650 blue (450 nm) laser. The parameters used to print each sample are shown in Table II. Furthermore, as described above, any of the powder compositions of experimental alloys X2-X7 can be formed by gas atomization. As an example, gas-atomized X3 alloy powder was printed using the powder-feed DED machine described above, using the same printing parameters as shown in Table II, except that laser power outputs of 230 W, 240 W, 245 W, 250 W, 260 W, and 270 W were used. The printed samples were cut, and the crack density and hardness of each printed sample were measured. The results of the crack density measurements and hardness measurements are shown in Table III.

[0053] [Table 2]

[0054] [Table 3]

[0055] Furthermore, samples printed with gas-sprayed alloy raw material powder can be improved by including at least one of boron, zirconium, or carbon. For example, by changing the composition of gas-sprayed X3250W alloy powder by adding 0.1 wt% boron, the crack density was increased to 0.44 mm / mm 2 It was found that this reduced the crack density to 0.26 mm / mm². Furthermore, samples printed with modified compositions of gas-sprayed X3 250W alloy powder containing 0.5 wt%, 1.0 wt%, 1.5 wt%, and 2.0 wt% zirconium showed crack densities of 0.26 mm / mm², respectively. 2 , 0.34mm / mm 2 , 0.14mm / mm 2 , and 0.03 mm / mm 2 It was found that this could be further reduced.

[0056] It should be noted that the embodiments described herein are provided solely for illustrative purposes and are not intended to be construed as limitations of the invention. While the invention has been described with reference to exemplary embodiments, it should be understood that the terms used herein are descriptive and illustrative, not limiting. Modifications may be made within the scope and spirit of the appended claims, as described and amended, in such embodiments. While the invention is described herein with reference to specific means, materials, and embodiments, the invention is not intended to be limited to the details disclosed herein. Rather, the invention extends to all functionally equivalent structures, methods, and uses, such as those within the scope of the appended claims.

Claims

1. Nickel-based alloy compositions for additive manufacturing, 4-9% by weight of aluminum, 6-15% by weight of cobalt, 4-26% by weight of chromium, 2-5% by weight of tantalum, 3 to 13% by weight of tungsten, and A nickel-based alloy composition containing the remainder nickel.

2. Up to 8% by weight of molybdenum, Up to 1% by weight of titanium, and The nickel-based alloy composition according to claim 1, further comprising at least one of up to 4% by weight of niobium.

3. The nickel-based alloy composition according to claim 1, wherein the composition of aluminum is 4.5 to 7.7% by weight, the composition of cobalt is 7.7 to 12.9% by weight, the composition of chromium is 5 to 23% by weight, the composition of tantalum is 2.5 to 4.8% by weight, and the composition of tungsten is 3.3 to 11% by weight.

4. Up to 7.0% by weight of molybdenum, Up to 0.9% by weight of titanium, and The nickel-based alloy composition according to claim 3, further comprising at least one of up to 2.8% by weight of niobium.

5. Additive-manufactured part comprising the nickel-based alloy composition described in claim 1, wherein the part is High temperature crack index less than 2.0, Shale porridge zone below 250K, A porridge-like zone with a blood glucose level of less than 100K, Gamma prime phase fraction at 1200K: 40-67 mol%, Gamma prime formation temperature below 1500K, The phase close-packed (TCP) formation temperature is 900K to 1650K. 1.50 mm / mm ２ Crack density less than, or 350HV ０．３ ~560HV ０．３ Additive-manufactured part further comprising at least one of the hardnesses.

6. The aforementioned composition is Al: 3.9 to 7.2% by weight, Co: 6.4 to 12.0% by weight, Cr: 14.0 to 26.0% by weight, Mo: 0.4 to 0.7% by weight, Ta: 2.2 to 4.0% by weight, Ti: 0.5 to 0.9% by weight, W: 6.7 to 12.4% by weight, and Ni: The nickel-based alloy composition according to claim 1, including the remainder.

7. The nickel-based alloy composition according to claim 5, wherein the composition of aluminum is 4.7 to 6.3% by weight, the composition of cobalt is 7.8 to 10.6% by weight, the composition of chromium is 17.0 to 23.0% by weight, the composition of molybdenum is 0.4 to 0.6% by weight, the composition of tantalum is 2.6 to 3.6% by weight, the composition of titanium is 0.6 to 0.8% by weight, and the composition of tungsten is 8.1 to 10.9% by weight.

8. The aforementioned composition is Al: 3.9 to 7.2% by weight, Co: 6.4 to 12.0% by weight, Cr: 5.7 to 10.7% by weight, Mo: 4.2 to 7.8% by weight, Ta: 2.2 to 4.0% by weight, Ti: 0.5 to 0.9% by weight, W: 6.7 to 12.4% by weight, and Ni: The nickel-based alloy composition according to claim 1, including the remainder.

9. The nickel-based alloy composition according to claim 9, wherein the composition of aluminum is 4.7 to 6.3% by weight, the composition of cobalt is 7.8 to 10.6% by weight, the composition of chromium is 7.0 to 9.4% by weight, the composition of molybdenum is 5.1 to 6.9% by weight, the composition of tantalum is 2.6 to 3.6% by weight, the composition of titanium is 0.6 to 0.8% by weight, and the composition of tungsten is 8.1 to 10.9% by weight.

10. Up to 0.2% by weight of carbon, A maximum of 0.2% by weight of boron, or The nickel-based alloy composition according to claim 9, further comprising at least one of up to 3% by weight of zirconium.

11. The aforementioned composition is Al: 3.9 to 7.2% by weight, Co: 6.4 to 12.0% by weight, Cr: 5.7 to 10.7% by weight, Mo: 0.4 to 0.7% by weight, Nb: 1.5 to 2.9% by weight, Ta: 2.2 to 4.0% by weight, W: 2.8 to 5.2% by weight, and Ni: The nickel-based alloy composition according to claim 1, including the remainder.

12. The nickel-based alloy composition according to claim 13, wherein the composition of aluminum is 4.7 to 6.3% by weight, the composition of cobalt is 7.8 to 10.6% by weight, the composition of chromium is 7.0 to 9.4% by weight, the composition of molybdenum is 0.4 to 0.6% by weight, the composition of niobium is 1.9 to 2.5% by weight, the composition of tantalum is 2.6 to 3.6% by weight, and the composition of tungsten is 3.4 to 4.6% by weight.

13. The aforementioned composition is Al: 3.9 to 7.2% by weight, Co: 6.4 to 12.0% by weight, Cr: 7.1 to 13.3% by weight, Mo: 0.4 to 0.7% by weight, Ta: 2.2 to 4.0% by weight, Ti: 0.5 to 0.9% by weight, W: 5.3 to 9.8% by weight, and Ni: The nickel-based alloy composition according to claim 1, including the remainder.

14. The nickel-based alloy composition according to claim 17, wherein the composition of aluminum is 4.7 to 6.3% by weight, the composition of cobalt is 7.8 to 10.6% by weight, the composition of chromium is 8.7 to 11.7% by weight, the composition of molybdenum is 0.4 to 0.6% by weight, the composition of tantalum is 2.6 to 3.6% by weight, the composition of titanium is 0.6 to 0.8% by weight, and the composition of tungsten is 6.4 to 8.6% by weight.

15. The aforementioned composition is Al: 4.6 to 8.5% by weight, Co: 7.7 to 14.3% by weight, Cr: 4.2 to 7.8% by weight, Ta: 2.2 to 4.0% by weight, W: 5.6 to 10.4% by weight, and Ni: The nickel-based alloy composition according to claim 1, including the remainder.

16. The nickel-based alloy composition according to claim 15, wherein the composition of aluminum is 5.5 to 7.5% by weight, the composition of cobalt is 9.4 to 12.7% by weight, the composition of chromium is 5.1 to 6.9% by weight, the composition of tantalum is 2.6 to 3.6% by weight, and the composition of tungsten is 6.8 to 9.2% by weight.

17. The aforementioned composition is Al: 4.6 to 8.5% by weight, Co: 7.0 to 13.0% by weight, Cr: 5.6 to 10.4% by weight, Ta: 2.8 to 5.2% by weight, W: 4.2 to 7.8% by weight; and Ni: The nickel-based alloy composition according to claim 1, including the remainder.

18. The nickel-based alloy composition according to claim 17, wherein the composition of aluminum is 5.5 to 7.5% by weight, the composition of cobalt is 8.5 to 11.5% by weight, the composition of chromium is 6.8 to 9.2% by weight, the composition of tantalum is 3.4 to 4.6% by weight, and the composition of tungsten is 5.1 to 6.9% by weight.

19. Additive-manufactured parts, Including nickel-based alloy compositions, Additive-manufactured parts having a high-temperature crack index of less than 2.0, a shale porridge zone below 250 K, an equilibrium porridge zone below 100 K, a gamma-prime phase fraction of 40-65 mol% at 1200 K, a gamma-prime formation temperature below 1500 K, and a TCP formation temperature of 900 K-1600 K.

20. Additive-manufactured parts, Including nickel-based alloy compositions, 1.50 mm / mm ２ Crack density less than 350 HV ０．３ ~560HV ０．３ Additive manufacturing part having a hardness of [value].

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