阅读说明：本技术 一种孪晶强化的镍基高温合金及其制备方法和应用 (Twin crystal strengthened nickel-based high-temperature alloy and preparation method and application thereof ) 是由 张建新 李盼 金辉鑫 张友健 王子晗 于 2020-05-12 设计创作，主要内容包括：本发明提供一种孪晶强化的镍基高温合金及其制备方法和应用,属于高温合金技术领域。所述镍基高温合金由以下重量百分比的成分组成：Co：20.0～30.0％,Cr：10.0～15.0％,Mo：1.0～4.0％,W：1.0～5.0％,Al：3.0～9.0％,Ti：5.0～15.0％,Ta：1.0～7.0％,Re：1.0～8.0％,Ru：1.0～6.0％,余量为Ni。本发明通过优化合金成分,让合金在退火处理以及蠕变过程中可以产生孪晶,而孪晶界则可以阻挡位错滑移,进一步提高合金强度,同时降低了合金成本,因此具有良好的实际推广应用之价值。(The invention provides a twin crystal strengthened nickel-based superalloy and a preparation method and application thereof, and belongs to the technical field of superalloys. The nickel-based superalloy consists of the following components in percentage by weight: co: 20.0-30.0%, Cr: 10.0-15.0%, Mo: 1.0-4.0%, W: 1.0-5.0%, Al: 3.0-9.0%, Ti: 5.0-15.0%, Ta: 1.0-7.0%, Re: 1.0-8.0%, Ru: 1.0-6.0% and the balance of Ni. The invention can generate twin crystal in the annealing treatment and creep process by optimizing the alloy components, and the twin crystal boundary can block dislocation sliding, thereby further improving the alloy strength and simultaneously reducing the alloy cost, and having good practical popularization and application values.)

1. The twin crystal strengthened nickel-based superalloy is characterized by comprising the following components in percentage by weight:

co: 20.0-30.0%, Cr: 10.0-15.0%, Mo: 1.0-4.0%, W: 1.0-5.0%, Al: 3.0-9.0%, Ti: 5.0-15.0%, Ta: 1.0-7.0%, Re: 1.0-8.0%, Ru: 1.0-6.0% and the balance of Ni.

2. The twin strengthened nickel-base superalloy as in claim 1, wherein the nickel-base superalloy consists of the following composition in weight percent:

co: 25.0%, Cr: 10.0 percent; mo: 3.0 percent; w: 3.0 percent; al: 5.0 percent; ti: 10.0 percent; ta: 5.0 percent; re: 1.0 percent; ru: 1.0% and the balance of Ni.

3. The twin strengthened nickel-base superalloy as in claim 1, wherein the nickel-base superalloy consists of the following composition in weight percent:

co: 20.0%, Cr: 15.0 percent; mo: 2.0 percent; w: 2.0 percent; al: 6.0 percent; ti: 5.0 percent; ta: 2.0 percent; re: 2.0 percent; ru: 3.0 percent and the balance of Ni.

4. The twin strengthened nickel-base superalloy as in claim 1, wherein the nickel-base superalloy consists of the following composition in weight percent:

co: 30.0%, Cr: 12.0 percent; mo: 1.0 percent; w: 1.0 percent; al: 3.0 percent; ti: 15.0 percent; ta: 1.0 percent; re: 6.0 percent; ru: 5.0 percent, and the balance being Ni.

5. The method of producing the twin strengthened nickel base superalloy of any of claims 1 to 4, wherein the method comprises: smelting the alloy element raw materials to enable the raw materials to be evenly smelted to obtain cast materials, and then carrying out heat treatment on the cast materials.

6. The method according to claim 5, wherein the melting is performed by an arc melting furnace.

7. The method according to claim 5, wherein the heat treatment process comprises in particular: keeping the temperature at 1050-; air cooling after aging at 620-680 ℃ for 20-28 hours; then air cooling is carried out after aging for 18-22 hours at 750-800 ℃.

8. The method according to claim 7, wherein the heat treatment process comprises: keeping the temperature at 1100 ℃ for 5 hours, and then cooling in air; air cooling is carried out after aging is carried out for 24 hours at 660 ℃; then air cooling is carried out after aging for 20 hours at 760 ℃.

9. Use of the twin crystal strengthened nickel-base superalloy as defined in any of claims 1 to 4 or the nickel-base superalloy prepared by the method as defined in any of claims 5 to 8 in any one or more of the following:

1) a gas turbine component or preparing a gas turbine component;

2) an aircraft engine component or preparing an aircraft engine component;

3) chemical plant components or prepared chemical plant components;

4) turbocharger rotors or preparing turbocharger rotors;

5) or preparing the high-temperature furnace component.

10. The use of claim 9, wherein in 2) the aircraft engine component comprises an aircraft engine turbine blade.

Technical Field

The invention belongs to the technical field of high-temperature alloys, and particularly relates to a twin crystal strengthened nickel-based high-temperature alloy and a preparation method and application thereof.

Background

The information in this background section is only for enhancement of understanding of the general background of the invention and is not necessarily to be construed as an admission or any form of suggestion that this information forms the prior art that is already known to a person of ordinary skill in the art.

The nickel-based high-temperature alloy has excellent high-temperature performance and is a key material for manufacturing advanced aeroengines and gas turbine blades at present. In order to meet the continuously developing requirements of high-performance aircraft engines, it is necessary to develop nickel-based single crystal superalloys having good high-temperature strength and other combination properties, in particular good durability and structural stability. Modern nickel-based alloys usually contain more than ten elements, and particularly, refractory elements with high melting point and large atomic radius play a good role in solid solution strengthening, so that the service temperature of the alloys is increased. For example, in the case of a CMSX series single crystal alloy, the total addition of refractory elements in the first generation is 14.6 (wt%), the second generation is 16.4 (wt%), and the third generation is up to 20.7 (wt%), significantly improving the high temperature creep and fatigue fracture properties of the alloy.

With the development of nickel-based high-temperature alloy, the content of refractory elements is continuously improved, so that the proportion of precipitation strengthening gamma' phase is as high as about 70%, the refractory elements such as Re, W and the like are seriously segregated in the gamma phase, and the alloy presents very high supersaturation. Since solid solution strengthening elements such as Re and W are also main elements that effectively form a TCP phase (topologically close-packed phase), the tendency of the TCP phase to precipitate during high-temperature use of the single crystal alloy increases. On one hand, the formation of the TCP phase consumes a large amount of Mo, Re, Cr, W and other solid solution strengthening elements, and weakens the solid solution strengthening effect of the matrix phase; on the other hand, the needle-like or flake-like TCP phase is often the origin of cracks and the channel for rapid crack propagation, which leads to the reduction of the endurance life of the high-temperature alloy, and the obvious deterioration of plasticity and toughness, and seriously affects the high-temperature mechanical properties of the alloy.

In general, in the past, the strength of the nickel-based superalloy is improved mainly through the solid solution strengthening of a large amount of solute elements, the principle is that solute atoms can block the slippage of dislocation, but the inventor finds that the addition of a large amount of expensive alloy elements greatly improves the alloy cost, and is not beneficial to the large-scale application of the nickel-based superalloy.

Disclosure of Invention

Aiming at the problems in the prior art, the invention aims to provide a twin crystal reinforced nickel-based high-temperature alloy and a preparation method and application thereof.

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

in a first aspect of the invention, a twin crystal strengthened nickel-based superalloy is provided, which comprises the following components in percentage by weight:

co: 20.0-30.0%, Cr: 10.0-15.0%, Mo: 1.0-4.0%, W: 1.0-5.0%, Al: 3.0-9.0%, Ti: 5.0-15.0%, Ta: 1.0-7.0%, Re: 1.0-8.0%, Ru: 1.0-6.0% and the balance of Ni.

In a second aspect of the present invention, there is provided a method for preparing the twin crystal strengthened nickel-base superalloy, comprising: smelting the alloy element raw materials to enable the raw materials to be evenly smelted to obtain cast materials, and then carrying out heat treatment on the cast materials.

Wherein, the smelting is preferably carried out by adopting an electric arc smelting furnace;

the heat treatment process specifically comprises: keeping the temperature at 1050-; air cooling after aging at 620-680 ℃ for 20-28 hours; then air cooling is carried out after aging is carried out for 18-22 hours at 750-800 ℃; further preferably, the temperature is kept at 1100 ℃ for 5 hours, and then air cooling is carried out; air cooling is carried out after aging is carried out for 24 hours at 660 ℃; then air cooling is carried out after aging for 20 hours at 760 ℃. According to the invention, by optimizing the alloy components, twin crystals can be generated in the annealing treatment and creep process of the alloy, and the twin crystal boundary can block dislocation slip, so that the alloy strength is further improved, and the alloy cost is reduced.

In a third aspect of the invention, there is provided the use of the twin crystal strengthened nickel base superalloy described above in any one or more of:

1) a gas turbine component or preparing a gas turbine component;

2) an aircraft engine component or preparing an aircraft engine component;

3) chemical plant components or prepared chemical plant components;

4) turbocharger rotors or preparing turbocharger rotors;

5) or preparing the high-temperature furnace component.

Wherein in 2) the aircraft engine component comprises an aircraft engine turbine blade.

The beneficial technical effects of one or more technical schemes are as follows:

the nickel-based high-temperature alloy obtained by reasonably using the elements in the specific proportion in the technical scheme has excellent high-temperature strength and durability, does not contain noble metal elements, has lower cost and is more beneficial to industrial production;

according to the technical scheme, each alloy element can generate twin crystals in the annealing treatment and creep deformation processes, so that dislocation movement is hindered, the effect of strengthening the high-temperature alloy is achieved, the alloy cost is reduced, the nickel-based high-temperature alloy prepared in the technical scheme is applied to the fields of engine turbine blades and the like, the use requirement under the condition of long-time high temperature can be effectively met, and the nickel-based high-temperature alloy has good practical application value.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings according to the provided drawings without creative efforts.

FIG. 1 is a diagram showing the morphology of twin crystals existing in the creep deformation process of the alloy in example 1 of the present invention.

Detailed Description

It is to be understood that the following detailed description is exemplary and is intended to provide further explanation of the invention as claimed. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof, unless the context clearly indicates otherwise.

As mentioned above, the strength of the nickel-base superalloy is improved mainly by solid solution strengthening of a large amount of solute elements, the principle is that solute atoms can block slippage of dislocation, and the addition of a large amount of expensive alloy elements greatly improves the alloy cost, which is not beneficial to large-scale application of the nickel-base superalloy.

In view of the above, in an exemplary embodiment of the present invention, a twin crystal strengthened nickel-based superalloy is provided, which is composed of the following components in percentage by weight:

co: 20.0-30.0%, Cr: 10.0-15.0%, Mo: 1.0-4.0%, W: 1.0-5.0%, Al: 3.0-9.0%, Ti: 5.0-15.0%, Ta: 1.0-7.0%, Re: 1.0-8.0%, Ru: 1.0-6.0% and the balance of Ni.

In the twin crystal reinforced nickel-based high-temperature alloy, Co element can effectively reduce stacking fault energy of a matrix, improve the probability of occurrence of faults and widen the faults, thereby hindering diffusion dislocation slippage, reducing creep rate, increasing creep resistance and improving high-temperature strength.

Cr element enters a matrix phase to play a role in solid solution strengthening, and can also effectively reduce the stacking fault energy of the solid solution and improve the high-temperature durable strength of the alloy; in addition, Cr can form Cr on the surface of the alloy₂O₃And the oxide film protects the alloy from high-temperature oxidation and corrosion. However, too high Cr content in the nickel-base alloy promotes an increased tendency to precipitate the TCP phase, which is a harmful phase, and deteriorates the structural stability of the alloy. Therefore, the control range of the Cr content in the invention is 10.0-15.0%.

The atomic radius of Mo and W elements is larger than that of Ni atoms, so that the alloy has strong solid solution strengthening effect on gamma and gamma' phases, and the heat strength of the alloy can be effectively improved. However, W, Mo is also an element forming TCP phase, so too high content of W, Mo causes precipitation of harmful TCP phase and block carbide, and lowers the high temperature mechanical properties of the alloy, therefore, the content of W element in the present invention is controlled to 1.0-4.0%, and the content of W element is controlled to 1.0-5.0%.

Both Al and Ti elements are gamma prime phase forming elements, the content of which determines the percentage content of the strengthening phase gamma' of the alloy and the degree of strengthening thereof. Further, Al element is also an antioxidant element, and Ti is also an MC carbide-forming element. Therefore, the Al element content is controlled to be 3.0-9.0%, and the Ti element content is controlled to be 5.0-15.0%, so that the high-temperature resistance and durability of the alloy are effectively improved.

Ta is also one of the main forming elements of the gamma' -phase in the nickel-based single crystal superalloy, and can also effectively improve the heat strength of the alloy and improve the casting performance of the alloy, but the excessive Ta can increase the eutectic content in the alloy and increase the difficulty of heat treatment. Therefore, the amount of Ta added in the alloy is controlled to be Ta 1.0-7.0%.

The Re element and Ru element are platinum group elements and are effective alloy components for improving oxidation resistance, and when 0.5% or more of either element is added, the effect is remarkable, but when the element is added in excess, harmful phases are induced to be formed, so that the amount of Re element added in the alloy is controlled to be Re: 1.0-8.0%; the addition amount of the Re element is controlled to be Ru: 1.0 to 6.0 percent.

In another embodiment of the present invention, the nickel-base superalloy consists of the following components in weight percent:

co: 25.0%, Cr: 10.0 percent; mo: 3.0 percent; w: 3.0 percent; al: 5.0 percent; ti: 10.0 percent; ta: 5.0 percent; re: 1.0 percent; ru: 1.0% and the balance of Ni.

In another embodiment of the present invention, the nickel-base superalloy consists of the following components in weight percent:

co: 20.0%, Cr: 15.0 percent; mo: 2.0 percent; w: 2.0 percent; al: 6.0 percent; ti: 5.0 percent; ta: 2.0 percent; re: 2.0 percent; ru: 3.0 percent and the balance of Ni.

In another embodiment of the present invention, the nickel-base superalloy consists of the following components in weight percent:

co: 30.0%, Cr: 12.0 percent; mo: 1.0 percent; w: 1.0 percent; al: 3.0 percent; ti: 15.0 percent; ta: 1.0 percent; re: 6.0 percent; ru: 5.0 percent, and the balance being Ni.

In another embodiment of the present invention, a method for preparing the twin crystal strengthened nickel-base superalloy is provided, the method comprising: smelting the alloy element raw materials to enable the raw materials to be evenly smelted to obtain cast materials, and then carrying out heat treatment on the cast materials.

Wherein, the smelting is preferably carried out by adopting an electric arc smelting furnace;

the heat treatment process specifically comprises: keeping the temperature at 1050-; air cooling after aging at 620-680 ℃ for 20-28 hours; then air cooling is carried out after aging is carried out for 18-22 hours at 750-800 ℃; further preferably, the temperature is kept at 1100 ℃ for 5 hours, and then air cooling is carried out; air cooling is carried out after aging is carried out for 24 hours at 660 ℃; then air cooling is carried out after aging for 20 hours at 760 ℃. According to the invention, by optimizing the alloy components, twin crystals can be generated in the annealing treatment and creep process of the alloy, and the twin crystal boundary can block dislocation slip, so that the alloy strength is further improved, and the alloy cost is reduced.

In a third aspect of the invention, there is provided the use of the twin crystal strengthened nickel base superalloy described above in any one or more of:

1) a gas turbine component or preparing a gas turbine component;

2) an aircraft engine component or preparing an aircraft engine component;

3) chemical plant components or prepared chemical plant components;

4) turbocharger rotors or preparing turbocharger rotors;

5) or preparing the high-temperature furnace component.

Wherein in 2) the aircraft engine component comprises an aircraft engine turbine blade.

The invention is further illustrated by the following examples, which are not to be construed as limiting the invention thereto. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention.