A B-class nickel-based multi-principal element alloy, a preparation method and application thereof

Abstract

This invention provides a nickel-based multi-principal-element alloy containing type B, its preparation method, and its application. The nickel-based multi-principal-element alloy containing type B has the general formula AlCoCrNb. (6‑x) Ni 76 B x Where 0% ≤ x ≤ 1%, and x is the atomic percentage content. This invention achieves a synergistic improvement in alloy strength and toughness by precisely controlling the relative ratio of non-metallic element B to metallic element Nb in a soft and tough face-centered cubic (FCC) solid solution matrix, utilizing a combination of microalloying of B and grain boundary engineering. This invention also discloses a method for preparing and applying B-type nickel-based multi-principal element alloys. The B-type nickel-based multi-principal element alloys of this invention not only possess excellent room-temperature mechanical properties (such as high tensile strength, high yield strength, and good elongation), but also exhibit potential high-temperature stability, oxidation resistance, wear resistance, and corrosion resistance.

Description

Technical Field

[0001] This invention relates to alloy technology, and more particularly to a nickel-based multi-principal-element alloy containing type B, its preparation method, and its application. Background Technology

[0002] With engineering applications demanding increasingly higher performance from structural materials under extreme service environments, the compositional design and microstructure of multi-principal element alloys have become important research directions in the field of metallic materials. Among them, nickel-based multi-principal element alloys with face-centered cubic (FCC) solid solutions as the matrix exhibit excellent ductility. Furthermore, introducing alloying elements such as Al and Nb into the matrix can effectively improve the material's high-temperature stability, oxidation resistance, wear resistance, and corrosion resistance. However, single FCC solid solution phases often exhibit low room-temperature yield strength, severely limiting the application of this type of alloy in engineering fields. To improve the strength of nickel-based multi-principal element alloys, microalloying combined with grain boundary engineering is a crucial strategy in current alloy design. In existing alloy systems, the addition of larger-radius atoms such as Nb can provide a certain solid solution strength, while the introduction of the non-metallic element B can improve grain boundary morphology.

[0003] In nickel-based multi-principal alloys, the interaction between metallic and non-metallic elements has a significant impact on the alloy's microstructure and mechanical properties. However, balancing strength and ductility remains a challenge in nickel-based multi-principal alloys: how to precisely control the relative proportions of non-metallic element B and metallic element Nb to introduce high-strength precipitates into the soft and tough FCC matrix, and to fully utilize the role of B in grain boundary engineering. Therefore, there is an urgent need to develop a novel B-containing nickel-based multi-principal alloy to achieve a synergistic improvement in strength and ductility, while simultaneously acquiring excellent high-temperature stability, oxidation resistance, wear resistance, and corrosion resistance. Summary of the Invention

[0004] The purpose of this invention is to address the problem of low room temperature yield strength in single FCC solid solution phase nickel-based multi-principal alloys by providing a B-type nickel-based multi-principal alloy. This alloy achieves a good balance of high strength and toughness, high temperature stability, oxidation resistance, wear resistance, and corrosion resistance by precisely controlling the ratio of non-metallic element B to metallic element Nb and combining it with a specific preparation process.

[0005] It should be noted that, in this invention, unless otherwise specified, the specific meaning of "comprising" in relation to composition and description includes both open-ended meanings such as "comprising," "including," etc., and closed-ended meanings such as "composed of," "consisting of," etc., and similar meanings.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: a nickel-based multi-principal-element alloy containing type B, wherein the main elements of the alloy are Al, Co, Cr, Ni, Nb and B, with the general formula AlCoCrNb.(6-x) Ni 76 B x Where 0% < x ≤ 1%, and x is the atomic percentage content.

[0007] Furthermore, the general formula AlCoCrNb (6-x) Ni 76 B x In the middle: 0.3% ≤ x ≤ 0.5%.

[0008] Furthermore, the nickel-based multi-principal-element alloy containing type B has a tensile strength of 1295~1328 MPa, a yield strength of 936~988 MPa, and a fracture elongation of 17%~22%.

[0009] Another object of the present invention discloses a method for preparing a nickel-based multi-principal-element alloy containing type B, comprising the following steps: weighing each component according to the general formula; placing Al, Co, Cr, Ni, Nb and B into a copper crucible in a vacuum arc melting furnace, and placing a pre-prepared Ti ingot into another copper crucible; closing the furnace door and evacuating to a vacuum of 2.5 × 10⁻⁶. -3 ~3×10 -3 After Pa, high-purity argon gas is introduced in reverse to -0.06~-0.04 MPa; after arc initiation, Ti ingots are first melted, and then the alloy raw materials are melted to obtain a nickel-based multi-principal element alloy containing type B.

[0010] Furthermore, before smelting, the surfaces of the metallic elemental raw materials Al, Co, Cr, Ni, and Nb are polished to remove surface oxide scale and impurities. The non-metallic element B is selected as a high-purity blocky elemental as raw material and does not undergo the above polishing process. The polished metallic elemental raw materials Al, Co, Cr, Ni, and Nb are placed in separate containers, ethanol is poured in, and ultrasonic cleaning is performed. After being fully dried, they are placed in sealed bags for later use. The non-metallic element B does not participate in the above cleaning process and is directly placed in a sealed bag for later use.

[0011] Furthermore, the polishing is performed using different grades of SiC sandpaper (80#, 240#, and 600#).

[0012] Furthermore, during ultrasonic cleaning, the metallic raw materials are cleaned 2 to 4 times, with each cleaning cycle lasting 5 to 10 minutes.

[0013] Furthermore, the purity of the metallic elemental raw materials Al, Co, Cr, Ni and Nb is greater than or equal to 99.95 wt.%, and the purity of the non-metallic element B is greater than or equal to 99.999 wt.%.

[0014] Furthermore, B is a high-purity, blocky element.

[0015] Furthermore, when weighing the elemental raw materials, the weighing error is ±0.001g.

[0016] Furthermore, when placing the elemental raw materials, B is placed at the bottom of the copper crucible, while the metallic elemental raw materials Al, Co, Cr, Ni and Nb are placed on top of B.

[0017] Furthermore, when smelting Ti ingots, the smelting process is repeated 2-4 times, with each smelting lasting 50-70 seconds, to remove excess oxygen as much as possible. Furthermore, when smelting the alloy raw materials, the melting process involves repeatedly turning and remelting the materials 5 to 7 times, with each melting cycle lasting 90 to 120 seconds, in order to obtain a uniform microstructure.

[0018] Another objective of this invention is to disclose the application of a type B nickel-based multi-principal-element alloy in the field of engineering structural components.

[0019] Furthermore, the engineering structural components are high-strength bolts for aircraft engines, high-load fasteners, drive shafts, or landing gear load-bearing joints.

[0020] Furthermore, the engineering structural component is a high-performance cold-drawing die, a precision cold-stamping punch, or an ultra-high pressure vessel liner.

[0021] This invention, while maintaining constant contents of Al, Co, Cr, and Ni, precisely controls the relative ratio of B to Nb in the alloy by microalloying of B to replace part of the Nb element, thus designing and preparing alloys with the general formula AlCoCrNb. (6-x) Ni 76 B x A nickel-based multi-principal element alloy containing type B (where 0% ≤ x ≤ 1%). This alloy significantly improves its overall mechanical properties through the coupling effect of a soft face-centered cubic FCC solid solution and grain boundary engineering, overcoming the low room-temperature yield strength defect of a single FCC solid solution phase. Specifically, this invention has the following advantages: 1. This invention realizes the microalloying design of non-metallic element B in nickel-based multi-principal alloys containing B-type nickel. By precisely controlling the ratio of Al, Co, Cr, Ni, Nb and B, a nickel-based multi-principal alloy with both high strength and good plasticity is obtained, overcoming the defect of low room temperature yield strength of single FCC solid solution phase.

[0022] 2. The nickel-based multi-principal element alloy containing type B of the present invention not only exhibits excellent room temperature mechanical properties (tensile strength 1295~1328 MPa, yield strength 936~988 MPa, elongation at break 17%~22%), but also the synergistic introduction of Al, Nb and B elements significantly improves the alloy's high temperature stability, oxidation resistance, wear resistance and corrosion resistance, making it have broad application prospects in the field of engineering structures.

[0023] 3. Compared with existing nickel-based multi-principal alloys, the nickel-based multi-principal alloy containing B in this invention exhibits typical dendritic and interdendritic structures in the as-cast state. XRD confirms that it is a single-phase FCC structure. At the same time, the introduction of B element makes the grain boundaries serrated. Through the coupling effect of grain boundary engineering and FCC matrix, the strength and toughness are synergistically improved.

[0024] 4. The nickel-based multi-principal alloy of the present invention has the characteristics of high melting point and good fluidity, which is suitable for casting complex structural parts and can achieve integral molding, which is conducive to engineering promotion and application.

[0025] In summary, this invention has successfully developed a nickel-based multi-principal element alloy with a face-centered cubic (FCC) solid solution as the matrix and the use of B element to improve grain boundaries by precisely controlling the ratio of non-metallic element B and metallic element Nb, as well as its preparation method. While maintaining good ductility, it significantly improves the room temperature strength of the alloy, thereby achieving excellent strength and toughness matching, and simultaneously obtaining potential high-temperature stability, oxidation resistance, wear resistance and corrosion resistance. Attached Figure Description

[0026] Figure 1 Example 1: AlCoCrNb 5.7 Ni 76 B 0.3 Microstructure of nickel-based multi-principal-element alloys in the as-cast state; Figure 2 Example 1: AlCoCrNb 5.7 Ni 76 B 0.3 XRD patterns of nickel-based multi-principal element alloys in the as-cast state; Figure 3 Example 1: AlCoCrNb 5.7 Ni 76 B 0.3 Stress-strain curves of nickel-based multi-principal-element alloys under as-cast conditions at room temperature under tensile stress-strain conditions; Figure 4 Example 2 AlCoCrNb 5.5 Ni 76 B 0.5 Microstructure of nickel-based multi-principal-element alloys in the as-cast state; Figure 5 Example 2 AlCoCrNb 5.5 Ni 76 B 0.5 XRD patterns of nickel-based multi-principal element alloys in the as-cast state; Figure 6 Example 2 AlCoCrNb 5.5 Ni 76 B 0.5 Stress-strain curves of nickel-based multi-principal-element alloys under as-cast conditions at room temperature during tensile engineering. Detailed Implementation

[0027] The present invention will be further described below with reference to embodiments. The description of the technical features described below is based on representative embodiments and specific examples of the present invention, but the present invention is not limited to these embodiments and specific examples. It should be noted that: Unless otherwise stated, all units used in this specification are international standard units, and all numerical values ​​and ranges appearing in this invention should be understood to include systematic errors that are unavoidable in industrial production.

[0028] In this specification, the range of values ​​referred to as "value A to value B" refers to the range including the endpoint values ​​A and B.

[0029] In this specification, the numerical range indicated by "above" or "below" refers to the numerical range that includes the stated number.

[0030] In this specification, the word "may" has two meanings: to perform a certain process and not to perform a certain process.

[0031] In this specification, the terms "optional" or "optional" are used to indicate the use or omission of certain substances, components, procedures, application conditions, etc.

[0032] In this instruction manual, when "room temperature" or "room temperature" is used, the temperature can be 15-25℃.

[0033] Unless otherwise specified, all reagents or instruments used in this instruction manual are commercially available products. Example 1

[0034] This embodiment discloses a nickel-based multi-principal-element alloy containing type B alloy, with the general formula AlCoCrNb. 5.7 Ni 76 B 0.3 The specific preparation method is as follows: Step 1, Grinding: Use different grades (80#, 240#, and 600#) of SiC sandpaper to grind the surface of the metallic raw materials Al, Co, Cr, Ni, and Nb (purity 99.95 wt.%) to remove the oxide scale and impurities. Non-metallic element B is selected as a high-purity blocky element (purity 99.999 wt.%) and does not undergo the above grinding process.

[0035] Step 2, Cleaning: Place the polished elemental metals Al, Co, Cr, Ni, and Nb into separate beakers, add alcohol, and perform ultrasonic cleaning. During ultrasonic cleaning, the elemental metals are cleaned three times, with each cleaning cycle lasting 8 minutes. After thorough drying, place them in sealed bags for later use. High-purity blocky elemental boron is not included in this cleaning process.

[0036] Step 3, Batching: Calculate the mass percentage based on the molar percentage of the B-type nickel-based multi-principal alloy. Using a total mass of 70 g for each alloy ingot, weigh each element using an electronic balance. The weighed masses of Al, Co, Cr, Ni, Nb, and B are 1.947 g, 4.252 g, 3.752 g, 6.368 g, 53.642 g, and 0.039 g, respectively, with a weighing error of ±0.001 g.

[0037] Step 4, Melting: Powdered graphite is placed at the bottom of a copper crucible in the electric arc melting furnace, while the elemental metals Al, Co, Cr, Ni, and Nb are placed on top of the bulk boron. The pre-prepared Ti ingot is placed in another copper crucible. The furnace door is closed, and a vacuum of 2.8 × 10⁻⁶ is created. -3 After Pa, high-purity argon gas is introduced in reverse to -0.05 MPa. After arc ignition, the Ti ingot is first melted three times, each time for 60 s, to remove excess oxygen as much as possible. Then, the mixed raw materials are melted, repeatedly turned and melted six times, each time for 110 s, to obtain a uniform microstructure, ultimately yielding AlCoCrNb. 5.7 Ni 76 B 0.3 Nickel-based multi-principal-element alloys.

[0038] Figure 1 Example AlCoCrNb 5.7 Ni 76 B 0.3 The microstructure of a nickel-based multi-principal alloy in the as-cast state. This nickel-based multi-principal alloy exhibits an equiaxed crystal structure with serrated grain boundaries.

[0039] Figure 2 Example AlCoCrNb 5.7 Ni 76 B 0.3 The XRD pattern of the nickel-based multi-principal-element alloy in the as-cast state shows that the alloy has an FCC single-phase structure.

[0040] Figure 3 Example AlCoCrNb 5.7 Ni 76 B 0.3The room temperature tensile stress-strain curves of the nickel-based multi-principal element alloy in the as-cast state show that the tensile strength, yield strength and fracture plasticity are 1294 MPa, 946 MPa and 22%, respectively, exhibiting extremely excellent mechanical properties. Example 2

[0041] This embodiment discloses a nickel-based multi-principal-element alloy containing type B alloy, with the general formula AlCoCrNb. 5.5 Ni 76 B 0.5 The preparation method of the B-type nickel-based multi-principal-element alloy in this embodiment is the same as that in Example 1.

[0042] Figure 4 Example AlCoCrNb 5.5 Ni 76 B 0.5 The microstructure of the nickel-based multi-principal alloy in the as-cast state shows that the alloy exhibits a typical equiaxed grain structure with serrated grain boundaries.

[0043] Figure 5 Example AlCoCrNb 5.5 Ni 76 B 0.5 The XRD pattern of the nickel-based multi-principal-element alloy in the as-cast state shows that the alloy has an FCC single-phase structure.

[0044] Figure 6 Example AlCoCrNb 5.5 Ni 76 B 0.5 The room temperature tensile stress-strain curves of the nickel-based multi-principal element alloy in the as-cast state show that the tensile strength, yield strength and fracture plasticity are 1331 MPa, 1011 MPa and 16.5% of the compressive strength, yield strength and fracture plasticity, respectively, which also demonstrate extremely excellent mechanical properties.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nickel-based multi-principal element alloy containing type B, characterized in that, The general formula is AlCoCrNb (6-x) Ni 76 B x Where 0% < x ≤ 1%, and x is the atomic percentage content.

2. The nickel-based multi-principal-element alloy containing type B according to claim 1, characterized in that, The general formula AlCoCrNb (6-x) Ni 76 B x In the middle: 0.3% ≤ x ≤ 0.5%.

3. The nickel-based multi-principal-element alloy containing type B according to claim 1, characterized in that, The nickel-based multi-principal-element alloy containing type B has a tensile strength of 1295~1328 MPa, a yield strength of 936~988 MPa, and a fracture elongation of 17%~22%.

4. A method for preparing a nickel-based multi-principal element alloy containing type B as described in any one of claims 1-3, characterized in that, Includes the following steps: Weigh each component according to the general formula; place Al, Co, Cr, Ni, Nb, and B into a copper crucible in a vacuum arc melting furnace, and place the pre-prepared Ti ingot into another copper crucible; close the furnace door and evacuate to 2.5 × 10⁻⁶. -3 ~3×10 -3 After Pa, high-purity argon gas is introduced in reverse to -0.06~-0.04 MPa; after arc initiation, Ti ingots are first melted, and then the alloy raw materials are melted to obtain a nickel-based multi-principal element alloy containing type B.

5. The method for preparing a nickel-based multi-principal-element alloy containing type B according to claim 4, characterized in that, Before smelting, the surfaces of the elemental metal raw materials Al, Co, Cr, Ni and Nb are polished. The polished elemental metal raw materials Al, Co, Cr, Ni and Nb are placed in separate containers, ethanol is poured in, and ultrasonic cleaning is performed. After being fully dried, they are placed in sealed bags for later use.

6. The method for preparing a nickel-based multi-principal-element alloy containing type B according to claim 4, characterized in that, The purity of the metallic elemental raw materials Al, Co, Cr, Ni and Nb is greater than or equal to 99.95 wt.%, and the purity of the non-metallic element B is greater than or equal to 99.999 wt.%.

7. The method for preparing a nickel-based multi-principal element alloy containing type B according to claim 4, characterized in that, When placing elemental raw materials, B is placed at the bottom of the copper crucible, while the metallic elemental raw materials Al, Co, Cr, Ni and Nb are placed on top of B.

8. The method for preparing a nickel-based multi-principal element alloy containing type B according to claim 4, characterized in that, When smelting Ti ingots, smelt 2 to 4 times, with each smelting lasting 50 to 70 seconds.

9. The method for preparing a nickel-based multi-principal-element alloy containing type B according to claim 4, characterized in that, When smelting alloy raw materials, repeatedly turn and smelt 5 to 7 times, with each smelting time being 90 to 120 seconds.

10. The application of the nickel-based multi-principal alloy containing type B as described in any one of claims 1-3 in the field of preparing engineering structural components.

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