阅读说明：本技术 一种粉末镍基高温合金及其制备方法 (Powder nickel-based high-temperature alloy and preparation method thereof ) 是由 李云平 滕剑威 于 2020-05-14 设计创作，主要内容包括：本发明公开了一种粉末镍基高温合金及其制备方法,合金各元素质量百分数分别为：Cr:15.0％～25.0％；W:15.0％～25.0％；Co:9.0％～15.0％；Mo:0.5％～3.0％；Al:0.5％～4.0％；Ti:0.5％～1.5％；C:0.001％～0.20％；Sc:0.001％～0.20％；Y:0.001％～0.50％；Ni:余量。本发明充分利用合金的强化元素、抗氧化元素以及微量元素之间的协调作用,同时通过平衡热力学计算优化其他的合金元素含量,在保证合金抗氧化性能的基础上,综合提高合金的力学性能,尤其高温性能中强度和塑性同步提高,满足了新一代航空发动机涡轮盘以及热端部件的要求。(The invention discloses a powder nickel-based high-temperature alloy and a preparation method thereof, wherein the alloy comprises the following elements in percentage by mass: 15.0 to 25.0 percent of Cr; 15.0 to 25.0 percent of W; 9.0 to 15.0 percent of Co; 0.5 to 3.0 percent of Mo; 0.5 to 4.0 percent of Al; 0.5 to 1.5 percent of Ti; 0.001 to 0.20 percent of C; sc is 0.001 to 0.20 percent; 0.001 to 0.50 percent of Y; the balance being Ni. The invention fully utilizes the coordination among the strengthening elements, the antioxidant elements and the trace elements of the alloy, optimizes the content of other alloy elements by balancing thermodynamic calculation, comprehensively improves the mechanical property of the alloy on the basis of ensuring the oxidation resistance of the alloy, particularly synchronously improves the strength and the plasticity in high-temperature property, and meets the requirements of a turbine disc and a hot end part of a new generation of aeroengine.)

1. The powder nickel-based superalloy is characterized by comprising the following elements in percentage by mass: 15.0 to 25.0 percent of Cr; 15.0 to 25.0 percent of W; 9.0 to 15.0 percent of Co; 0.5 to 3.0 percent of Mo; 0.5 to 4.0 percent of Al; 0.5 to 1.5 percent of Ti; 0.001 to 0.20 percent of C; sc is 0.001 to 0.20 percent; 0.001 to 0.50 percent of Y; the balance being Ni.

2. The powder nickel-base superalloy according to claim 1, wherein the content of Mo and W is as follows: 1.3 to 1.9 percent of Mo; 16.0 to 19.0 percent of W.

3. The powder nickel-base superalloy as claimed in claim 1, wherein the content of Al and Ti is: 1.9 to 2.3 percent of Al; 0.5 to 0.7 percent of Ti.

4. The powder nickel-base-superalloy as in claim 1 or 3, wherein the amount of Cr, Y is: 19.0 to 24.0 percent of Cr; 0.03 to 0.12 percent of Y.

5. The powder nickel-base superalloy as claimed in claim 1, wherein the contents of Sc and C are: sc is 0.02 to 0.05 percent; 0.11 to 0.14 percent of C.

6. The powder nickel-base superalloy according to claim 1 or 5, wherein the content of Co is 11.0% to 13.0%.

7. A method for preparing the powder nickel-base superalloy as set forth in any of claims 1 to 6, comprising the steps of: (1) smelting an alloy ingot with a target component by an induction heating method; (2) preparing alloy powder from the alloy ingot by an atomization method; (3) putting the alloy powder into a sheath, and performing hot isostatic pressing treatment to obtain a hot isostatic pressing material; (4) carrying out hot extrusion on the hot isostatic pressing material to obtain an extruded bar; (5) removing the sheath of the extruded bar to obtain a nickel-based superalloy bar; (6) and annealing the nickel-based high-temperature alloy bar to obtain the powder nickel-based high-temperature alloy.

8. The method for preparing powder nickel-base superalloy according to claim 7, wherein in the step (2), the alloy is atomized by using nitrogen or inert gas, and the gas flow rate is 0.02-0.24m³The gas pressure is 0.5-0.9MPa, and the temperature of the atomized melt is 1400-1500 ℃; the granularity of the alloy powder in the step (2) is 10-150 mu m.

9. According to claimThe method for preparing the powder nickel-base superalloy as set forth in claim 7, wherein the hot isostatic pressing treatment in the step (3) comprises the following specific operation steps: firstly, alloy powder is put into a package sleeve and pumped at the temperature of 550 ℃ under the temperature of 450-^-4Compacting the powder under Pa; and then carrying out hot isostatic pressing treatment in an inert gas protective environment, wherein the hot isostatic pressing pressure is 150MPa-180MPa, the temperature is 1100-1200 ℃, and the heat preservation time is 120-300 min.

10. The method for preparing powder nickel-base superalloy according to claim 7, wherein the step (4) of hot pressing comprises the following specific steps: firstly, preheating a hot isostatic pressing material to an extrusion temperature, preheating an extrusion cylinder to the temperature of 300-; then carrying out extrusion treatment, wherein the extrusion temperature is 1130-1200 ℃, and the extrusion ratio is 13-16: 1, the extrusion pressure is 950-1100MPa, and the extrusion speed is 170-260 mm/s; the temperature of the annealing treatment in the step (6) is 1100-1200 ℃, and the time is 30-120 min.

Technical Field

The invention belongs to the technical field of alloys, and particularly relates to a powder Ni-based high-temperature alloy and a preparation method thereof.

Background

The Ni-based high-temperature alloy is a key material of important parts such as a turbine disc, a hot-end part and the like on an aeroengine. With the continuous development and improvement of thrust level of an aircraft engine and the flight speed of a missile, the currently used Ni-based high-temperature alloy gradually cannot meet the requirements of higher and higher service temperature and the like, and is easy to have defects of oxidation, cracks and the like, so that the service life and the service performance of the aircraft engine are influenced. Therefore, research and development of a Ni-based superalloy with excellent mechanical properties are required to meet the higher use requirements of an aircraft engine.

Disclosure of Invention

The invention aims to solve the technical problem of overcoming the defects and shortcomings in the background art and provide a Ni-based high-temperature alloy with excellent mechanical property and oxidation resistance and a preparation method thereof.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

the powder nickel-based high-temperature alloy comprises the following elements in percentage by mass: 15.0 to 25.0 percent of Cr; 15.0 to 25.0 percent of W; 9.0 to 15.0 percent of Co; 0.5 to 3.0 percent of Mo; 0.5 to 4.0 percent of Al; 0.5 to 1.5 percent of Ti; 0.001 to 0.20 percent of C; sc is 0.001 to 0.20 percent; 0.001 to 0.50 percent of Y; the balance being Ni.

Further, the contents of Mo and W are as follows: 1.3 to 1.9 percent of Mo; 16.0 to 19.0 percent of W.

Further, the contents of Al and Ti are as follows: 1.9 to 2.3 percent of Al; 0.5 to 0.7 percent of Ti.

Further, the contents of Cr and Y are as follows: 19.0 to 24.0 percent of Cr; 0.03 to 0.12 percent of Y.

Further, the contents of Sc and C are as follows: sc is 0.02 to 0.05 percent; 0.11 to 0.14 percent of C.

Further, the content of Co is 11.0% -13.0%.

The invention provides a preparation method of the powder nickel-based superalloy, which comprises the following steps: (1) smelting an alloy ingot with a target component by an induction heating method; (2) preparing alloy powder from the alloy ingot by an atomization method; (3) putting the alloy powder into a sheath, and performing hot isostatic pressing treatment to obtain a hot isostatic pressing material; (4) carrying out hot extrusion on the hot isostatic pressing material to obtain an extruded bar; (5) removing the sheath of the extruded bar to obtain a nickel-based superalloy bar; (6) and annealing the nickel-based high-temperature alloy bar to obtain the powder nickel-based high-temperature alloy.

Further, alloy atomization in the step (2) is adoptedAtomizing nitrogen or inert gas with gas flow of 0.02-0.24m³The gas pressure is 0.5-0.9MPa, and the temperature of the atomized melt is 1400-1500 ℃; the granularity of the alloy powder in the step (2) is 10-150 mu m.

Further, the hot isostatic pressing treatment in the step (3) comprises the following specific operation steps: firstly, alloy powder is put into a package sleeve and pumped at the temperature of 550 ℃ under the temperature of 450-^-4Compacting the powder under Pa; and then carrying out hot isostatic pressing treatment in an inert gas protective environment, wherein the hot isostatic pressing pressure is 150MPa-180MPa, the temperature is 1100-1200 ℃, and the heat preservation time is 120-300 min.

Further, the hot extrusion treatment in the step (4) comprises the following specific operation steps: firstly, preheating a hot isostatic pressing material to an extrusion temperature, preheating an extrusion cylinder to the temperature of 300-; then carrying out extrusion treatment, wherein the extrusion temperature is 1130-1200 ℃, and the extrusion ratio is 13-16: 1, the extrusion pressure is 950-1100MPa, and the extrusion speed is 170-260 mm/s; the temperature of the annealing treatment in the step (6) is 1100-1200 ℃, and the time is 30-120 min.

Compared with the prior art, the invention has the advantages that:

on the basis of the research of the existing polycrystalline Ni-based high-temperature alloy, the invention provides a component design idea of a novel Ni-based high-temperature alloy simultaneously added with Co and Sc, fully utilizes the coordination among strengthening elements, antioxidant elements and trace elements of the alloy, optimizes the contents of other alloy elements by balancing thermodynamic calculation, comprehensively improves the mechanical property of the alloy on the basis of ensuring the antioxidant property of the alloy, particularly synchronously improves the strength and plasticity in the high-temperature property, and meets the requirements of a turbine disc and a hot end part of a new-generation aero-engine.

Detailed Description

In order to facilitate an understanding of the present invention, the present invention will be described more fully and in detail with reference to the preferred embodiments, but the scope of the present invention is not limited to the specific embodiments below.

Unless otherwise defined, all terms of art used hereinafter have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention.

Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.

The powder Ni-based high-temperature alloy with excellent mechanical property and complete oxidation resistance, which is disclosed by the invention, comprises the following elements in percentage by mass: 15.0 to 25.0 percent of Cr; 15.0 to 25.0 percent of W; 9.0 to 15.0 percent of Co; 0.5 to 3.0 percent of Mo; 0.5 to 4.0 percent of Al; 0.5 to 1.5 percent of Ti; 0.001 to 0.20 percent of C; sc is 0.001 to 0.20 percent; 0.001 to 0.50 percent of Y; the balance being Ni.

According to the invention, the solid solution strengthening effect is achieved by adding elements such as Mo and W, but the stability of the structure is reduced and the oxidation resistance of the alloy is damaged due to the excessively high content of the element Mo, so that the content of the Mo in the invention is 0.5-3.0%, and more preferably 1.3-1.9%; too high a content of element W similarly reduces the stability of the alloy, but too low a content will not fully dissolve in the matrix to exert the solid solution strengthening effect, so the content of element W in the present application is 15.0% to 25.0%, more preferably 16.0% to 19.0%.

Since addition of Ti, Al, etc. elements to form a precipitate strengthens the precipitate, and excessive content of Al and Ti elements is detrimental to the workability of the alloy and affects the stability of the structure, the Al and Ti contents in the present application are 0.5% to 4.0% (more preferably 1.9% to 2.3%) and 0.5% to 1.5% (more preferably 0.5% to 0.7%), respectively.

Elements such as Cr, Al and Y are added to ensure the oxidation resistance of the alloy, but the high-temperature strength of the alloy is influenced by the excessively high Cr element, so that the content of the Cr element is 15.0-25.0%, more preferably 19.0-24.0%, and the content of the Y element is 0.001-0.50%, more preferably 0.03-0.12%.

The addition of trace elements Sc and C can improve the grain boundary strength by segregation in the grain boundary, wherein the element C forms M₆C improves the strength of the alloy at high temperature, and Sc can refine grains to improve the strength of the alloy. The content of C in the application is 0.001-0.20%,more preferably 0.11 to 0.14%, and the Sc content is 0.001 to 0.20%, more preferably 0.02 to 0.05%.

The addition of Co element to reduce the stacking fault can improve the creep and plasticity of the alloy and improve the processing performance of the alloy, but the high content of Co can reduce the strength of the alloy and influence the stability of the alloy, so that the content of Co is 9.0-15.0%, and more preferably 11.0-13.0%.

Meanwhile, the addition of the alloy element Co and the alloy element Sc can simultaneously improve the tensile strength and the elongation after fracture of the Ni-based high-temperature alloy at room temperature and high temperature, and has no obvious influence on the oxidation resistance.

In one embodiment, the method for preparing the Ni-based superalloy of the present invention comprises the steps of: (1): firstly, smelting an alloy ingot with a target component by an induction heating method; (2): preparing alloy powder from the alloy ingot by an atomization method; (3): putting the alloy powder into a stainless steel sheath, and performing hot isostatic pressing treatment to obtain a hot isostatic pressing material; (4): carrying out hot extrusion on the hot isostatic pressing material at high temperature to obtain an extruded bar; (5): removing the sheath of the extruded bar to obtain a Ni-based high-temperature alloy bar; (6): and carrying out short-time annealing treatment on the obtained extruded bar to finally obtain the Ni-based high-temperature alloy with excellent mechanical property and complete oxidation resistance.

Preferably, the smelting process of the target master alloy in the step (1) is carried out in a vacuum or argon protection mode.

Preferably, the alloy atomization in the step (2) adopts nitrogen or argon atomization, and the gas flow is 0.02-0.24m³The gas pressure is 0.5-0.9MPa, and the temperature of the atomized melt is 1400-1500 ℃.

Preferably, the particle size of the alloy powder in step (2) is selected to be 10-150 μm.

Preferably, the hot isostatic pressing treatment in step (3) comprises the following specific operation steps: firstly, alloy powder is put into a package sleeve and pumped at the temperature of 450-^-4Compacting the powder under Pa; and then carrying out hot isostatic pressing treatment in an argon protective environment, wherein the hot isostatic pressing pressure is 150MPa-180MPa, the temperature is 1100-1200 ℃, and the heat preservation time is 120-300 min.

Preferably, the hot extrusion treatment in the step (4) comprises the following specific operation steps: firstly, preheating a hot isostatic pressing material to an extrusion temperature, preheating an extrusion cylinder to the temperature of 300-; then carrying out extrusion treatment, wherein the extrusion temperature is 1130-1200 ℃, and the extrusion ratio is 13-16: 1, the extrusion pressure 950-.

Preferably, the sheath treatment in the step (5) adopts a wire-cut electric discharge machine to cut off the stainless steel sheath on the outer layer of the sample after the hot extrusion.

Preferably, the temperature of the annealing treatment in the step (6) is 1100-1200 ℃, and the time is 30-120 min.