High-strength high-temperature-resistant alloy material for gas turbine casing and preparation method thereof

Abstract

The application relates to the technical field of high-temperature alloy materials, and discloses a high-strength high-temperature-resistant alloy material for a gas turbine casing and a preparation method thereof, which comprises the following raw materials in parts by mass: modified nickel powder 90-100 parts, chromium powder 20-25 parts, cobalt powder 8-10 parts, aluminum powder 2-3 parts, titanium powder 2.5-3 parts and molybdenum powder 3-4 parts. The modified nickel powder, the chromium powder, the cobalt powder, the aluminum powder, the titanium powder and the molybdenum powder are mixed, ball-milled, pressed and sintered to form an alloy material which has high mechanical strength at high temperatures, can meet the use requirements of high-temperature resistance and high strength of the gas turbine casing, and has the modified nickel powder with randomly distributed composite carbon fibers on the surface, which serves as a skeleton structure of the nickel powder, is dispersed at the interface of the alloy material and can hinder the crack propagation of the alloy, thereby enhancing the strength of the alloy material.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of high-temperature alloy materials, in particular to a high-strength high-temperature-resistant alloy material for a gas turbine casing and a preparation method thereof. BACKGROUND

[0002] The gas turbine is an internal combustion power machine taking continuous flow gas as working medium to drive the impeller to rotate at high speed and convert the energy of fuel into useful work. The gas turbine is a rotary impeller type heat engine. The material required by the key part, the casing, in the gas turbine should meet the long-term working conditions under high temperature, high pressure, cold and hot alternation, high-temperature oxidation corrosion, high-speed airflow scouring and the like. Therefore, the alloy material is usually selected as the gas turbine casing, and has the advantages of good high-temperature resistance, mechanical strength and corrosion resistance.

[0003] The high-temperature alloy refers to a kind of metal material taking iron, nickel and cobalt as matrix and capable of working at high temperature above 600 DEG C and under certain stress for a long time. The high-temperature alloy has good comprehensive properties such as oxidation resistance, thermal corrosion resistance, fatigue resistance, fracture toughness and plasticity, and is widely applied to the gas turbine casing. However, in the production and manufacturing process of the existing alloy, the interface bonding of nickel powder and other metal elements is prone to be poor in the sintering process, cracks are formed, and the mechanical properties and high-temperature resistance of the alloy material are affected. SUMMARY

[0004] The application provides a high-strength high-temperature-resistant alloy material for a gas turbine casing, and solves the problem that the interface bonding of nickel powder and other metal elements is prone to be poor in the sintering process, cracks are formed, and the mechanical properties and high-temperature resistance of the alloy material are affected.

[0005] The technical scheme of the application is as follows:

[0006] The high-strength high-temperature-resistant alloy material for the gas turbine casing comprises the following raw materials in parts by mass: modified nickel powder 90-100 parts, chromium powder 20-25 parts, cobalt powder 8-10 parts, aluminum powder 2-3 parts, titanium powder 2.5-3 parts and molybdenum powder 3-4 parts.

[0007] The modified nickel powder is obtained by mixing and reacting the modified nickel powder, the composite carbon fiber and the silane coupling agent after the modified nickel powder is coated on the surface of the nickel powder by the reaction of the benzene triol modified lignin and the acryloyl chloride.

[0008] The composite carbon fiber is obtained by mixing and reacting the zinc powder after the porous carbon layer is formed on the surface of the carbon fiber.

[0009] The preparation method of the high-strength high-temperature-resistant alloy material for the gas turbine casing comprises the following preparation steps:

[0010] S1, the modified nickel powder, the chromium powder, the cobalt powder, the aluminum powder, the titanium powder and the molybdenum powder are mixed, vacuum dried and ball milled to obtain a mixture;

[0011] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material.

[0012] Further, in step S1, vacuum drying is performed at a temperature of 90-100℃, a vacuum degree of 5-10Pa, and a drying time of 10-15min.

[0013] Furthermore, in step S1, the ball milling is carried out using a ball mill, the ball material is tungsten carbide with a diameter of 10 mm, the ball-to-material ratio in the ball mill is 10:1, the ball milling speed is 300-400 r / min, the ball milling time is 2-5 h, and the ball milling atmosphere is argon.

[0014] Furthermore, in step S2, the pressing pressure is 100-200 MPa, and the pressing time is 1-2 min.

[0015] Furthermore, in step S2, the sintering temperature is 1500-1550℃, the sintering time is 2-3h, and the sintering pressure is 30-40Pa.

[0016] Furthermore, the modified nickel powder is prepared by the following steps:

[0017] A1. Add carbon fiber and tannic acid to ethanol, stir evenly, add glucose, stir evenly, filter, wash, dry, add potassium hydroxide solution, purge with nitrogen gas, carbonize, cool to room temperature, take out, wash, dry, and obtain modified carbon fiber.

[0018] A2. Add modified carbon fiber and zinc powder to ethanol, stir at 100-150 r / min for 1-2 h, and after adsorption is complete, filter, wash, dry, place in a reaction furnace, calcine at 1000-1200℃ for 2-4 h, and cool to room temperature to obtain composite carbon fiber.

[0019] A3. Phenylene-modified lignin and triethylamine were added to N,N-dimethylformamide, stirred evenly, cooled, and then acryloyl chloride was added. After stirring and reacting, the temperature was raised and the reaction was stirred again. Deionized water was added, and after removing the organic solvent by rotary evaporation, the mixture was washed and dried to obtain the lignin derivative.

[0020] A4. Add the lignin derivative to ethanol, stir until homogeneous, add nickel powder, stir until homogeneous, heat and stir until the ethanol evaporates to obtain pretreated nickel powder;

[0021] A5. Add the composite carbon fiber to ethanol and deionized water, stir evenly, add silane coupling agent, stir until the reaction is complete, cool to room temperature, filter, wash, and dry to obtain double-bonded composite carbon fiber.

[0022] A6. Add pretreated nickel powder and double-bonded composite carbon fiber to N,N-dimethylformamide, stir evenly, add azobisisobutyronitrile, stir until the reaction is complete, cool to room temperature, filter, wash, and dry to obtain modified nickel powder.

[0023] Furthermore, in the A1 reaction process described above, tannic acid contains a large number of phenolic hydroxyl groups, which have good adhesion. As a binder, it allows the carbon precursor glucose to be coated onto the carbon fiber surface through tannic acid. After high-temperature carbonization, the glucose decomposes to form a dense carbon layer. Potassium hydroxide acts as an activator, and the potassium hydroxide molecules decompose to form channels on the surface of the dense carbon layer. This achieves the coating of the carbon fiber surface with a porous carbon layer, giving it a porous structure and excellent adsorption properties, thus obtaining modified carbon fiber.

[0024] Furthermore, during the A2 reaction process described above, the porous carbon layer on the surface of the modified carbon fiber contains a large number of pore structures and has good adsorption properties. It can load zinc powder onto the surface of the modified carbon fiber, so that the zinc powder is evenly distributed on the surface of the modified carbon fiber. At a high temperature of 1000-1200℃, the zinc powder is oxidized to generate zinc oxide vapor. The generated zinc oxide vapor is adsorbed on the surface of the modified carbon fiber to form zinc oxide crystal nuclei. As the reaction proceeds, the zinc oxide crystal nuclei grow in a directional manner to form four-needle-shaped zinc oxide whiskers, thereby achieving the formation of four-needle-shaped zinc oxide whiskers on the surface of the modified carbon fiber and obtaining composite carbon fiber.

[0025] Furthermore, in the A3 reaction process described above, triethylamine acts as a catalyst in N,N-dimethylformamide solvent, enabling the hydroxyl groups on the pyrogallol-modified lignin to react with acryloyl chloride, removing chlorine and allowing acryloyl chloride to be grafted onto the pyrogallol-modified lignin to obtain lignin derivatives.

[0026] Furthermore, during the A4 reaction process described above, the phenolic hydroxyl groups contained in the lignin derivative have high activity and adhesion properties, and can bind with nickel powder through hydrogen bonds, so that the lignin derivative coats the surface of the nickel powder to obtain pretreated nickel powder.

[0027] Furthermore, during the A5 reaction process described above, the hydroxyl groups generated by the hydrolysis of the silane coupling agent can combine with the hydroxyl groups contained on the surface of the composite carbon fiber, so that the silane coupling agent is uniformly grafted onto the surface of the composite carbon fiber, giving the composite carbon fiber reactive double bonds, and obtaining double-bonded composite carbon fiber.

[0028] Furthermore, in the A6 reaction process described above, azobisisobutyronitrile (AIBN) acts as an initiator, enabling the double bonds in the pretreated nickel powder to copolymerize with the double-bonded composite carbon fibers. This results in the composite carbon fibers being uniformly coated on the surface of the pretreated nickel powder, and the composite carbon fibers being randomly distributed on the surface of the pretreated nickel powder, forming a rough surface, thus obtaining modified nickel powder.

[0029] Further, in step A1, the mass ratio of carbon fiber, tannic acid, ethanol, glucose and potassium hydroxide solution is (4-5):(0.8-1):(100-150):(3.5-4):(2-3).

[0030] Further, in step A2, the mass ratio of modified carbon fiber, zinc powder and ethanol is (4-6):(2.5-3.5):(90-110).

[0031] Further, in step A3, the mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water is (1.4-1.6):(0.4-0.8):(20-25):(0.8-1.2):(150-200).

[0032] Further, in step A4, the mass ratio of lignin derivative, ethanol and nickel powder is (2-2.5):(45-50):(5-6).

[0033] Further, in step A5, the mass ratio of composite carbon fiber, ethanol, deionized water and silane coupling agent is (3-4):(50-60):(20-25):(1-1.5).

[0034] Further, in step A6, the mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide and azobisisobutyronitrile is (5-6):(2-2.5):(70-80):(0.5-0.7).

[0035] The present invention has the following beneficial effects:

[0036] (1) In the technical solution of the present invention, a porous carbon layer is formed on the surface of carbon fiber. On the one hand, the rich porosity of the porous carbon layer endows the carbon fiber with excellent adsorption performance and porous structure. As a synthesis site for tetraneedle zinc oxide whiskers, it is beneficial to form tetraneedle zinc oxide whiskers on the surface of carbon fiber and add them to the nickel-based alloy material to improve the strength and high temperature resistance of the nickel-based alloy material. On the other hand, during the high temperature sintering process, the porous carbon layer can form a metal carbide reinforcing phase with the alloy metal raw material and fill the gaps in the alloy material to improve the compactness of the alloy material, thereby improving the strength and high temperature resistance of the nickel-based alloy material. In addition, carbon fiber has excellent aspect ratio, strength and high temperature resistance. When it is inserted into the nickel-based alloy material, it improves the mechanical strength and high temperature resistance of the alloy.

[0037] (2) In the technical solution of the present invention, four needle-shaped zinc oxide whiskers are formed on the surface of modified carbon fiber. On the one hand, the four needle-shaped zinc oxide whiskers increase the contact area between the modified carbon fiber and the alloy metal raw material, which is conducive to the uniform dispersion of composite carbon fiber in the alloy material. Moreover, the formed four needle-shaped zinc oxide whiskers have a unique four-dimensional spatial structure. Four needle-shaped crystals extend from the core radial direction, which can form a mechanical interlock with the alloy material, improve the density of the alloy, and thus improve the strength and high temperature resistance of the alloy material. On the other hand, the modified carbon fiber serves as the carrier of the four needle-shaped zinc oxide whiskers, which improves the dispersion of the four needle-shaped zinc oxide whiskers in the alloy material. Moreover, the random distribution of the modified carbon fiber forms a network structure that can absorb and weaken stress, improve the compressive strength of the whiskers, and prevent the needle-shaped whiskers from being crushed when they are pressed into preforms, thus destroying their unique four-dimensional spatial structure and thereby improving the strength and high temperature resistance of the alloy material.

[0038] (3) In the technical solution of the present invention, the lignin derivative formed by the reaction of pyrogallol-modified lignin and acryloyl chloride is coated on the surface of nickel powder. On the one hand, the lignin derivative has good adhesion, which gives the nickel powder good bonding performance, so that the nickel powder and other metal powders form a uniform and dense mixture, which is conducive to the synthesis of a denser alloy material, so that the alloy material has higher mechanical strength and high temperature resistance. On the other hand, during the sintering process, the lignin derivative forms a dense carbon network structure, which forms metal carbides with the metal raw materials and is dispersed in the alloy material matrix, thereby improving the strength of the alloy material. In addition, the reactive double bonds contained in the lignin derivative are conducive to the composite carbon fiber coating on the surface of nickel powder to form a rough surface, further increasing the contact area between the metal raw materials and nickel powder, which can hinder the propagation of alloy cracks, enhance the strength and high temperature resistance of the alloy material, and improve the dispersion of composite carbon fiber in the alloy material, thereby improving the strength and high temperature resistance of the alloy material.

[0039] (4) In the technical solution of the present invention, the double bonds contained in the pretreated nickel powder can undergo a copolymerization reaction with the double bonded composite carbon fiber, so as to achieve uniform coating of the composite carbon fiber on the surface of the pretreated nickel powder. The composite carbon fiber is randomly distributed on the surface of the pretreated nickel powder to form a rough surface, which further increases the contact area between the metal raw material and the nickel powder, so that the metal raw material and the nickel powder are uniformly mixed. The carbon fiber is selected as nano carbon fiber with a diameter of 200nm and a length of 10μm, which can uniformly coat the surface of the nickel powder and serve as the skeleton structure of the nickel powder. It is dispersed at the interface of the alloy material, which can hinder the propagation of alloy cracks and enhance the strength of the alloy material.

[0040] The alloy material formed by mixing modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder and molybdenum powder, ball milling, pressing and sintering has high mechanical strength at high temperature, which can meet the high temperature resistance and high strength requirements of gas turbine casing. Attached Figure Description

[0041] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0042] Figure 1 This is a scanning electron microscope image of the alloy material prepared in Example 3 of the present invention.

[0043] Figure 2 This is a thermogravimetric analysis diagram of the alloy material of this invention.

[0044] Figure 3 This is a scanning electron microscope image of the alloy material prepared in Comparative Example 1 of this invention.

[0045] Figure 4 This is a scanning electron microscope image of the alloy material prepared in Comparative Example 4 of this invention. Detailed Implementation

[0046] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0047] The raw materials used in the embodiments of this invention are shown below, and all reagents used are analytical grade.

[0048] The nickel powder has a particle size of 2.5μm and a purity of 99.9%, and was purchased from Shanghai Shuitian Technology Co., Ltd.

[0049] The chromium powder has a particle size of 3.5 μm, the cobalt powder has a particle size of 3 μm, and both have a purity of 99.9%. They were purchased from Guangdong Daxiao Chemical Co., Ltd.

[0050] The aluminum powder had a particle size of 2.5 μm and a purity of 99.9%, and was purchased from Hunan Jinhao New Material Technology Co., Ltd.

[0051] The titanium powder with a particle size of 4.5μm and the product number is T109127, and the molybdenum powder with a particle size of 4.5μm and the product number is M141395, were purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0052] The carbon fiber is a nanofiber with a diameter of 200 nm and a length of 10 μm, purchased from Zhongke Jinyan (Beijing) Technology Co., Ltd.

[0053] The silane coupling agent is KH570 (γ-methacryloyloxypropyltrimethoxysilane).

[0054] The zinc powder used is nano zinc powder with a particle size of 100nm, purchased from Beijing Ruiante Technology Co., Ltd.

[0055] The enzymatically hydrolyzed lignin was purchased from Shandong Longli Biotechnology Co., Ltd.

[0056] Pyrogallol-modified lignin is prepared by the following steps:

[0057] Enzymatically hydrolyzed lignin and pyrogallol were added to a 65% (w / w) lithium chloride aqueous solution, stirred until homogeneous, and the pH was adjusted to 3.5 with 2.4 mol / L hydrochloric acid. The reaction was carried out at 110℃ for 2 h, cooled to room temperature, and the solid was collected by filtration. The solid was washed with ethanol to remove unreacted pyrogallol and dried at 40℃ for 48 h to obtain pyrogallol-modified lignin. The mass ratio of enzymatically hydrolyzed lignin, pyrogallol and lithium chloride aqueous solution was 2.5:0.8:50.

[0058] Example 1:

[0059] A high-strength, high-temperature resistant alloy material for gas turbine casings comprises the following raw materials in parts by weight: 90 parts modified nickel powder, 20 parts chromium powder, 8 parts cobalt powder, 2 parts aluminum powder, 2.5 parts titanium powder, and 3 parts molybdenum powder;

[0060] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0061] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 90℃, a vacuum degree of 5Pa, and a drying time of 10 minutes. The ball milling is performed using a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 300 r / min, the milling time is 2 hours, and the milling atmosphere is argon.

[0062] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 100MPa, the pressing time is 1min, the sintering temperature is 1500℃, the sintering time is 2h, and the sintering pressure is 30Pa.

[0063] Modified nickel powder is prepared by the following steps:

[0064] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added and stirred at 70℃ for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70℃ for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800℃ for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70℃ for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 4:0.8:100:3.5:2.

[0065] A2. Modified carbon fiber and zinc powder were added to ethanol and stirred at 100 r / min for 1 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70℃ for 10 min, placed in a reactor, and calcined at 1000℃ for 2 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of modified carbon fiber, zinc powder and ethanol was 4:2.5:90.

[0066] A3. Pyrogallol-modified lignin and triethylamine were added to N,N-dimethylformamide and stirred at 25°C and 80 r / min for 2 h. After cooling to 5°C, acryloyl chloride was added, and the reaction was continued for 3 h. The temperature was then raised to 40°C and stirred for 4 h. Deionized water was added, and the organic solvent was removed by rotary evaporation at 80°C. The mixture was washed three times with deionized water and dried in an oven at 70°C for 5 min to obtain the lignin derivative. The mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water was 1.4:0.4:20:0.8:150.

[0067] A4. Add the lignin derivative to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of lignin derivative, ethanol and nickel powder is 2:45:5.

[0068] A5. Add the composite carbon fiber to ethanol and deionized water, stir evenly, add KH570, stir and react at 70℃ for 1 hour, cool to room temperature, filter, wash 3 times with deionized water, and dry in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber; the mass ratio of composite carbon fiber, ethanol, deionized water and KH570 is 3:50:20:1.

[0069] A6. Pretreated nickel powder and double-bonded composite carbon fiber were added to N,N-dimethylformamide and stirred evenly. Azobisisobutyronitrile was then added, and the mixture was stirred and reacted at 75°C for 4 hours. After cooling to room temperature, the mixture was filtered, washed three times with deionized water, and dried in an oven at 70°C for 10 minutes to obtain modified nickel powder. The mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide, and azobisisobutyronitrile was 5:2:70:0.5.

[0070] Example 2:

[0071] A high-strength, high-temperature resistant alloy material for gas turbine casings comprises the following raw materials in parts by weight: 95 parts modified nickel powder, 23 parts chromium powder, 9 parts cobalt powder, 2.5 parts aluminum powder, 2.8 parts titanium powder, and 3.5 parts molybdenum powder;

[0072] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0073] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 95℃, a vacuum degree of 8Pa, and a drying time of 13 minutes. The ball milling is performed using a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 350 r / min, the milling time is 3 hours, and the milling atmosphere is argon.

[0074] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain an alloy material; wherein the pressing pressure is 150MPa, the pressing time is 1.5min, the sintering temperature is 1530℃, the sintering time is 2.5h, and the sintering pressure is 35Pa.

[0075] Modified nickel powder is prepared by the following steps:

[0076] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added and stirred at 70℃ for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70℃ for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800℃ for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70℃ for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 4.5:0.9:130:3.8:2.5.

[0077] A2. Modified carbon fiber and zinc powder were added to ethanol and stirred at 130 r / min for 1.5 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70 ℃ for 10 min, placed in a reactor, and calcined at 1100 ℃ for 3 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of modified carbon fiber, zinc powder and ethanol was 5:3:100.

[0078] A3. Pyrogallol-modified lignin and triethylamine were added to N,N-dimethylformamide and stirred at 25°C and 80 r / min for 2 h. After cooling to 5°C, acryloyl chloride was added, and the reaction was continued for 3 h. Then, the temperature was raised to 40°C and the reaction was stirred for 4 h. Deionized water was added, and the organic solvent was removed by rotary evaporation at 80°C. The mixture was washed three times with deionized water and dried in an oven at 70°C for 5 min to obtain the lignin derivative. The mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water was 1.5:0.6:23:1:180.

[0079] A4. Add the lignin derivative to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of lignin derivative, ethanol and nickel powder is 2.3:48:5.5;

[0080] A5. The composite carbon fiber was added to ethanol and deionized water, stirred evenly, KH570 was added, and the mixture was stirred and reacted at 70℃ for 1 hour. After cooling to room temperature, it was filtered, washed three times with deionized water, and dried in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber. The mass ratio of composite carbon fiber, ethanol, deionized water and KH570 was 3.5:55:23:1.3.

[0081] A6. Pretreated nickel powder and double-bonded composite carbon fiber were added to N,N-dimethylformamide and stirred evenly. Azobisisobutyronitrile was then added, and the mixture was stirred and reacted at 75°C for 4 hours. After cooling to room temperature, the mixture was filtered, washed three times with deionized water, and dried in an oven at 70°C for 10 minutes to obtain modified nickel powder. The mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide, and azobisisobutyronitrile was 5.5:2.3:75:0.6.

[0082] Example 3:

[0083] A high-strength, high-temperature resistant alloy material for a gas turbine casing comprises the following raw materials in parts by weight: 100 parts modified nickel powder, 25 parts chromium powder, 10 parts cobalt powder, 3 parts aluminum powder, 3 parts titanium powder, and 4 parts molybdenum powder.

[0084] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0085] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 100℃, a vacuum degree of 10Pa, and a drying time of 15 minutes. The ball milling process uses a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 400 r / min, the milling time is 5 hours, and the milling atmosphere is argon.

[0086] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 200MPa, the pressing time is 2min, the sintering temperature is 1550℃, the sintering time is 3h, and the sintering pressure is 40Pa.

[0087] Modified nickel powder is prepared by the following steps:

[0088] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added, and the mixture was stirred at 70°C for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70°C for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800°C for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70°C for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 5:1:150:4:3.

[0089] A2. Modified carbon fiber and zinc powder were added to ethanol and stirred at 150 r / min for 2 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70℃ for 10 min, placed in a reactor, and calcined at 1200℃ for 4 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of modified carbon fiber, zinc powder and ethanol was 6:3.5:110.

[0090] A3. Pyrogallol-modified lignin and triethylamine were added to N,N-dimethylformamide and stirred at 25°C and 80 r / min for 2 h. After cooling to 5°C, acryloyl chloride was added, and the reaction was continued for 3 h. The temperature was then raised to 40°C, and the reaction was stirred for 4 h. Deionized water was added, and the organic solvent was removed by rotary evaporation at 80°C. The mixture was washed three times with deionized water and dried in an oven at 70°C for 5 min to obtain the lignin derivative. The mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water was 1.6:0.8:25:1.2:200.

[0091] A4. Add the lignin derivative to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of lignin derivative, ethanol and nickel powder is 2.5:50:6.

[0092] A5. The composite carbon fiber was added to ethanol and deionized water, stirred evenly, KH570 was added, and the mixture was stirred and reacted at 70℃ for 1 hour. After cooling to room temperature, it was filtered, washed three times with deionized water, and dried in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber. The mass ratio of composite carbon fiber, ethanol, deionized water and KH570 was 4:60:25:1.5.

[0093] A6. Pretreated nickel powder and double-bonded composite carbon fiber were added to N,N-dimethylformamide and stirred evenly. Azobisisobutyronitrile was then added and stirred at 75°C for 4 hours. After cooling to room temperature, the mixture was filtered, washed three times with deionized water, and dried in an oven at 70°C for 10 minutes to obtain modified nickel powder. The mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide, and azobisisobutyronitrile was 6:2.5:80:0.7.

[0094] Comparative Example 1

[0095] A high-strength, high-temperature resistant alloy material for a gas turbine casing comprises the following raw materials in parts by weight: 100 parts modified nickel powder, 25 parts chromium powder, 10 parts cobalt powder, 3 parts aluminum powder, 3 parts titanium powder, and 4 parts molybdenum powder.

[0096] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0097] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 100℃, a vacuum degree of 10Pa, and a drying time of 15 minutes. The ball milling process uses a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 400 r / min, the milling time is 5 hours, and the milling atmosphere is argon.

[0098] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 200MPa, the pressing time is 2min, the sintering temperature is 1550℃, the sintering time is 3h, and the sintering pressure is 40Pa.

[0099] Modified nickel powder is prepared by the following steps:

[0100] A1. Carbon fiber and zinc powder were added to ethanol and stirred at 150 r / min for 2 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70℃ for 10 min, placed in a reactor, and calcined at 1200℃ for 4 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of carbon fiber, zinc powder and ethanol was 6:3.5:110.

[0101] A2. Pyrogallol-modified lignin and triethylamine were added to N,N-dimethylformamide and stirred at 25°C and 80 r / min for 2 h. After cooling to 5°C, acryloyl chloride was added, and the reaction was continued for 3 h. The temperature was then raised to 40°C and stirred for 4 h. Deionized water was added, and the organic solvent was removed by rotary evaporation at 80°C. The mixture was washed three times with deionized water and dried in an oven at 70°C for 5 min to obtain the lignin derivative. The mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water was 1.6:0.8:25:1.2:200.

[0102] A3. Add the lignin derivative to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of lignin derivative, ethanol and nickel powder is 2.5:50:6.

[0103] A4. Add the composite carbon fiber to ethanol and deionized water, stir evenly, add KH570, stir and react at 70℃ for 1 hour, cool to room temperature, filter, wash 3 times with deionized water, and dry in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber; the mass ratio of composite carbon fiber, ethanol, deionized water and KH570 is 4:60:25:1.5.

[0104] A5. Pretreated nickel powder and double-bonded composite carbon fiber were added to N,N-dimethylformamide and stirred evenly. Azobisisobutyronitrile was then added, and the mixture was stirred and reacted at 75°C for 4 hours. After cooling to room temperature, the mixture was filtered, washed three times with deionized water, and dried in an oven at 70°C for 10 minutes to obtain modified nickel powder. The mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide, and azobisisobutyronitrile was 6:2.5:80:0.7.

[0105] Comparative Example 2

[0106] A high-strength, high-temperature resistant alloy material for a gas turbine casing comprises the following raw materials in parts by weight: 100 parts modified nickel powder, 25 parts chromium powder, 10 parts cobalt powder, 3 parts aluminum powder, 3 parts titanium powder, and 4 parts molybdenum powder.

[0107] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0108] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 100℃, a vacuum degree of 10Pa, and a drying time of 15 minutes. The ball milling process uses a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 400 r / min, the milling time is 5 hours, and the milling atmosphere is argon.

[0109] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 200MPa, the pressing time is 2min, the sintering temperature is 1550℃, the sintering time is 3h, and the sintering pressure is 40Pa.

[0110] Modified nickel powder is prepared by the following steps:

[0111] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added, and the mixture was stirred at 70°C for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70°C for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800°C for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70°C for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 5:1:150:4:3.

[0112] A2. Pyrogallol-modified lignin and triethylamine were added to N,N-dimethylformamide and stirred at 25°C and 80 r / min for 2 h. After cooling to 5°C, acryloyl chloride was added, and the reaction was continued for 3 h. The temperature was then raised to 40°C and stirred for 4 h. Deionized water was added, and the organic solvent was removed by rotary evaporation at 80°C. The mixture was washed three times with deionized water and dried in an oven at 70°C for 5 min to obtain the lignin derivative. The mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water was 1.6:0.8:25:1.2:200.

[0113] A3. Add the lignin derivative to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of lignin derivative, ethanol and nickel powder is 2.5:50:6.

[0114] A4. Add the modified carbon fiber to ethanol and deionized water, stir evenly, add KH570, stir and react at 70℃ for 1 hour, cool to room temperature, filter, wash 3 times with deionized water, and dry in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber; the mass ratio of modified carbon fiber, ethanol, deionized water and KH570 is 4:60:25:1.5.

[0115] A5. Pretreated nickel powder and double-bonded composite carbon fiber were added to N,N-dimethylformamide and stirred evenly. Azobisisobutyronitrile was then added, and the mixture was stirred and reacted at 75°C for 4 hours. After cooling to room temperature, the mixture was filtered, washed three times with deionized water, and dried in an oven at 70°C for 10 minutes to obtain modified nickel powder. The mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide, and azobisisobutyronitrile was 6:2.5:80:0.7.

[0116] Comparative Example 3

[0117] A high-strength, high-temperature resistant alloy material for a gas turbine casing comprises the following raw materials in parts by weight: 100 parts modified nickel powder, 25 parts chromium powder, 10 parts cobalt powder, 3 parts aluminum powder, 3 parts titanium powder, and 4 parts molybdenum powder.

[0118] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0119] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 100℃, a vacuum degree of 10Pa, and a drying time of 15 minutes. The ball milling process uses a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 400 r / min, the milling time is 5 hours, and the milling atmosphere is argon.

[0120] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 200MPa, the pressing time is 2min, the sintering temperature is 1550℃, the sintering time is 3h, and the sintering pressure is 40Pa.

[0121] Modified nickel powder is prepared by the following steps:

[0122] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added, and the mixture was stirred at 70°C for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70°C for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800°C for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70°C for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 5:1:150:4:3.

[0123] A2. Modified carbon fiber and zinc powder were added to ethanol and stirred at 150 r / min for 2 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70℃ for 10 min, placed in a reactor, and calcined at 1200℃ for 4 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of modified carbon fiber, zinc powder and ethanol was 6:3.5:110.

[0124] A3. Add pyrogallol-modified lignin to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of pyrogallol-modified lignin, ethanol and nickel powder is 2.5:50:6.

[0125] A4. Add the composite carbon fiber to ethanol and deionized water, stir evenly, add KH570, stir and react at 70℃ for 1 hour, cool to room temperature, filter, wash 3 times with deionized water, and dry in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber; the mass ratio of composite carbon fiber, ethanol, deionized water and KH570 is 4:60:25:1.5.

[0126] A5. Pretreated nickel powder and double-bonded composite carbon fiber were added to N,N-dimethylformamide and stirred evenly. Azobisisobutyronitrile was then added, and the mixture was stirred and reacted at 75°C for 4 hours. After cooling to room temperature, the mixture was filtered, washed three times with deionized water, and dried in an oven at 70°C for 10 minutes to obtain modified nickel powder. The mass ratio of pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide, and azobisisobutyronitrile was 6:2.5:80:0.7.

[0127] Comparative Example 4

[0128] A high-strength, high-temperature resistant alloy material for a gas turbine casing comprises the following raw materials in parts by weight: 100 parts modified nickel powder, 25 parts chromium powder, 10 parts cobalt powder, 3 parts aluminum powder, 3 parts titanium powder, and 4 parts molybdenum powder.

[0129] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0130] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 100℃, a vacuum degree of 10Pa, and a drying time of 15 minutes. The ball milling process uses a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 400 r / min, the milling time is 5 hours, and the milling atmosphere is argon.

[0131] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 200MPa, the pressing time is 2min, the sintering temperature is 1550℃, the sintering time is 3h, and the sintering pressure is 40Pa.

[0132] Modified nickel powder is prepared by the following steps:

[0133] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added, and the mixture was stirred at 70°C for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70°C for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800°C for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70°C for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 5:1:150:4:3.

[0134] A2. Modified carbon fiber and zinc powder were added to ethanol and stirred at 150 r / min for 2 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70℃ for 10 min, placed in a reactor, and calcined at 1200℃ for 4 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of modified carbon fiber, zinc powder and ethanol was 6:3.5:110.

[0135] A3. The composite carbon fiber was added to ethanol and deionized water, stirred evenly, KH570 was added, and the mixture was stirred and reacted at 70℃ for 1 hour. After cooling to room temperature, it was filtered, washed three times with deionized water, and dried in an oven at 70℃ for 10 minutes to obtain double-bonded composite carbon fiber. The mass ratio of composite carbon fiber, ethanol, deionized water and KH570 was 4:60:25:1.5.

[0136] A4. Add nickel powder and double-bonded composite carbon fiber to N,N-dimethylformamide, stir evenly, add azobisisobutyronitrile, stir and react at 75℃ for 4h, cool to room temperature, filter, wash 3 times with deionized water, and dry in an oven at 70℃ for 10min to obtain modified nickel powder; the mass ratio of nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide and azobisisobutyronitrile is 6:2.5:80:0.7.

[0137] Comparative Example 5

[0138] A high-strength, high-temperature resistant alloy material for a gas turbine casing comprises the following raw materials in parts by weight: 100 parts modified nickel powder, 25 parts chromium powder, 10 parts cobalt powder, 3 parts aluminum powder, 3 parts titanium powder, and 4 parts molybdenum powder.

[0139] A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing includes the following preparation steps:

[0140] S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder, and molybdenum powder are mixed, vacuum dried, and then ball-milled to obtain a mixture. The vacuum drying process involves a temperature of 100℃, a vacuum degree of 10Pa, and a drying time of 15 minutes. The ball milling process uses a ball mill with tungsten carbide balls of 10mm diameter. The ball-to-material ratio in the ball mill is 10:1, the milling speed is 400 r / min, the milling time is 5 hours, and the milling atmosphere is argon.

[0141] S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material; wherein the pressing pressure is 200MPa, the pressing time is 2min, the sintering temperature is 1550℃, the sintering time is 3h, and the sintering pressure is 40Pa.

[0142] Modified nickel powder is prepared by the following steps:

[0143] A1. Carbon fiber and tannic acid were added to ethanol and stirred evenly. Glucose was added, and the mixture was stirred at 70°C for 30 min. After filtration, the mixture was washed three times with deionized water and dried in an oven at 70°C for 10 min. The mixture was then placed in a tube furnace, and a 30% potassium hydroxide solution was added. Nitrogen gas was introduced, and the mixture was carbonized at 800°C for 4 h. After cooling to room temperature, the mixture was removed, washed three times with deionized water, and dried in an oven at 70°C for 10 min to obtain modified carbon fiber. The mass ratio of carbon fiber, tannic acid, ethanol, glucose, and potassium hydroxide solution was 5:1:150:4:3.

[0144] A2. Modified carbon fiber and zinc powder were added to ethanol and stirred at 150 r / min for 2 h. After adsorption was complete, the mixture was filtered, washed three times with deionized water, dried in an oven at 70℃ for 10 min, placed in a reactor, and calcined at 1200℃ for 4 h. After cooling to room temperature, composite carbon fiber was obtained. The mass ratio of modified carbon fiber, zinc powder and ethanol was 6:3.5:110.

[0145] A3. Pyrogallol-modified lignin and triethylamine were added to N,N-dimethylformamide and stirred at 25°C and 80 r / min for 2 h. After cooling to 5°C, acryloyl chloride was added, and the reaction was continued for 3 h. The temperature was then raised to 40°C, and the reaction was stirred for 4 h. Deionized water was added, and the organic solvent was removed by rotary evaporation at 80°C. The mixture was washed three times with deionized water and dried in an oven at 70°C for 5 min to obtain the lignin derivative. The mass ratio of pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water was 1.6:0.8:25:1.2:200.

[0146] A4. Add the lignin derivative to ethanol, stir evenly, add nickel powder, stir at 70℃ for 30 min, raise the temperature to 85℃, stir until the ethanol evaporates, and obtain pretreated nickel powder; the mass ratio of lignin derivative, ethanol and nickel powder is 2.5:50:6.

[0147] A5. Add pretreated nickel powder and composite carbon fiber to N,N-dimethylformamide, stir evenly, add azobisisobutyronitrile, stir and react at 75℃ for 4h, cool to room temperature, filter, wash 3 times with deionized water, and dry in an oven at 70℃ for 10min to obtain modified nickel powder; the mass ratio of pretreated nickel powder, composite carbon fiber, N,N-dimethylformamide and azobisisobutyronitrile is 6:2.5:80:0.7.

[0148] The performance of the alloy materials prepared in Examples 1-3 and Comparative Examples 1-5 was then tested.

[0149] The tensile properties of the alloy material prepared above were tested at room temperature and at 850℃ according to GB / T 228.1-2021 standard.

[0150] As shown in Table 1 below.

[0151]

[0152] As can be seen from the data in Table 1, the alloy materials prepared in Examples 1-3 have high mechanical strength and high temperature resistance, and the reinforcing filler is coated on the surface of nickel powder, so that the filler is uniformly dispersed in the alloy material.

[0153] In Comparative Example 1, when modified carbon fiber was replaced with modified nickel powder prepared from carbon fiber and added to the alloy material, its mechanical properties and high-temperature resistance decreased. This demonstrates that forming a porous carbon layer on the surface of carbon fiber as a synthesis site for tetraneedle zinc oxide whiskers is beneficial to improving the strength and high-temperature resistance of nickel-based alloy materials. Furthermore, during high-temperature sintering, the porous carbon layer can form a metal carbide reinforcing phase with the alloy metal raw material, thereby improving the strength and high-temperature resistance of nickel-based alloy materials. In addition, as a carrier for tetraneedle zinc oxide whiskers, modified carbon fiber can prevent the tetraneedle zinc oxide whiskers from being crushed when pressed into preforms, thus improving the strength and high-temperature resistance of the alloy material.

[0154] In Comparative Example 2, when the composite carbon fiber was replaced with modified nickel powder prepared by modified carbon fiber and added to the alloy material, its mechanical properties and high temperature resistance decreased. This proves that the tetra-needle-shaped zinc oxide whiskers formed on the surface of the modified carbon fiber can form a mechanical interlock with the alloy material, improve the density of the alloy, and thus improve the strength and high temperature resistance of the alloy material.

[0155] In Comparative Example 3, when the lignin derivative was replaced with pyrogallol-modified lignin and the modified nickel powder was added to the alloy material, its mechanical properties and high-temperature resistance decreased. This proves that the reactive double bonds contained in the lignin derivative formed by the reaction of pyrogallol-modified lignin and acryloyl chloride are beneficial to the formation of a rough surface on the nickel powder by the composite carbon fiber coating, which further increases the contact area between the metal raw material and the nickel powder. This can hinder the propagation of alloy cracks, enhance the strength and high-temperature resistance of the alloy material, and improve the dispersibility of the composite carbon fiber in the alloy material, thereby improving the strength and high-temperature resistance of the alloy material.

[0156] In Comparative Example 4, when pretreated nickel powder was replaced with modified nickel powder prepared from nickel powder and added to the alloy material, its mechanical properties and high-temperature resistance decreased. This proves that lignin derivatives endow nickel powder with better bonding properties, enabling nickel powder and other metal powders to form a uniform and dense mixture, which is beneficial for synthesizing a denser alloy material. This results in the alloy material having higher mechanical strength and high-temperature resistance. Furthermore, during the sintering process, lignin derivatives form a dense carbon network structure, which forms metal carbides with the metal raw materials and is dispersed in the alloy material matrix, improving the strength of the alloy material.

[0157] In Comparative Example 5, when double-bonded composite carbon fibers were replaced with modified nickel powder prepared from composite carbon fibers and added to the alloy material, its mechanical properties and high-temperature resistance decreased. This proves that the composite carbon fibers are uniformly coated on the surface of the pretreated nickel powder. The composite carbon fibers are randomly distributed on the surface of the pretreated nickel powder, forming a rough surface, which allows the metal raw materials and nickel powder to be mixed uniformly. Moreover, the composite carbon fibers, as the skeleton structure of the nickel powder, are dispersed at the interface of the alloy material, which can hinder the propagation of alloy cracks and enhance the strength of the alloy material.

[0158] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0159] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described, or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in the claims, all of which should fall within the protection scope of the present invention.

Claims

1. A high-strength, high-temperature resistant alloy material for gas turbine casings, characterized in that, The raw materials include the following parts by weight: 90-100 parts modified nickel powder, 20-25 parts chromium powder, 8-10 parts cobalt powder, 2-3 parts aluminum powder, 2.5-3 parts titanium powder, and 3-4 parts molybdenum powder; The modified nickel powder is obtained by reacting pyrogallol-modified lignin and acryloyl chloride, coating it onto the surface of the nickel powder, and then mixing and reacting it with composite carbon fiber and silane coupling agent. The composite carbon fiber is obtained by forming a porous carbon layer on the surface of carbon fiber and then mixing and reacting it with zinc powder. The modified nickel powder is prepared by the following steps: A1. Add carbon fiber and tannic acid to ethanol, stir evenly, add glucose, stir evenly, filter, wash, dry, add potassium hydroxide solution, purge with nitrogen gas, carbonize, cool to room temperature, take out, wash, dry, and obtain modified carbon fiber. A2. Add modified carbon fiber and zinc powder to ethanol, stir at 100-150 r / min for 1-2 h, and after adsorption is complete, filter, wash, dry, place in a reaction furnace, calcine at 1000-1200℃ for 2-4 h, and cool to room temperature to obtain composite carbon fiber. A3. Phenylene-modified lignin and triethylamine were added to N,N-dimethylformamide, stirred evenly, cooled, and then acryloyl chloride was added. After stirring and reacting, the temperature was raised and the reaction was stirred again. Deionized water was added, and after removing the organic solvent by rotary evaporation, the mixture was washed and dried to obtain the lignin derivative. A4. Add the lignin derivative to ethanol, stir until homogeneous, add nickel powder, stir until homogeneous, heat and stir until the ethanol evaporates to obtain pretreated nickel powder; A5. Add the composite carbon fiber to ethanol and deionized water, stir evenly, add silane coupling agent, stir until the reaction is complete, cool to room temperature, filter, wash, and dry to obtain double-bonded composite carbon fiber. A6. Add pretreated nickel powder and double-bonded composite carbon fiber to N,N-dimethylformamide, stir evenly, add azobisisobutyronitrile, stir until the reaction is complete, cool to room temperature, filter, wash, and dry to obtain modified nickel powder.

2. The high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 1, characterized in that, In step A1, the mass ratio of the carbon fiber, tannic acid, ethanol, glucose and potassium hydroxide solution is (4-5):(0.8-1):(100-150):(3.5-4):(2-3).

3. The high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 1, characterized in that, In step A2, the mass ratio of the modified carbon fiber, zinc powder, and ethanol is (4-6):(2.5-3.5):(90-110).

4. The high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 1, characterized in that, In step A3, the mass ratio of the pyrogallol-modified lignin, triethylamine, N,N-dimethylformamide, acryloyl chloride, and deionized water is (1.4-1.6):(0.4-0.8):(20-25):(0.8-1.2):(150-200).

5. The high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 1, characterized in that, In step A4, the mass ratio of the lignin derivative, ethanol and nickel powder is (2-2.5):(45-50):(5-6).

6. The high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 1, characterized in that, In step A5, the mass ratio of the composite carbon fiber, ethanol, deionized water and silane coupling agent is (3-4):(50-60):(20-25):(1-1.5).

7. The high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 1, characterized in that, In step A6, the mass ratio of the pretreated nickel powder, double-bonded composite carbon fiber, N,N-dimethylformamide and azobisisobutyronitrile is (5-6):(2-2.5):(70-80):(0.5-0.7).

8. A method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing as described in any one of claims 1-7, characterized in that, The preparation steps include the following: S1. Modified nickel powder, chromium powder, cobalt powder, aluminum powder, titanium powder and molybdenum powder are mixed, vacuum dried and ball-milled to obtain a mixture; S2. The mixture is placed in a pressure mold to be pressed into a preform, and then the preform is placed in a sintering furnace for sintering and cooled to room temperature to obtain the alloy material.

9. The method for preparing a high-strength, high-temperature resistant alloy material for a gas turbine casing according to claim 8, characterized in that, The sintering temperature is 1500-1550℃, the sintering time is 2-3h, and the sintering pressure is 30-40Pa.

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