A preparation method of in-situ synthesizing ODS multi-principal element alloy powder

Abstract

The application is a preparation method of in-situ synthesis of ODS multi-principal element alloy powder. The method uses in-situ oxidation in the thermal spraying process and selective oxidation of Al or Cr in the alloy powder to introduce nano-oxides, and realizes uniform distribution of the nano-oxides in the alloy powder by high-speed impact and spatter of the powder at the liquid surface in the spraying process. After the spraying is completed, the alloy powder is rapidly cooled in the cooling liquid and still maintains the spherical shape. The ODS alloy powder prepared by the application has the advantages of uniform distribution of oxide particles in the powder and high powdering efficiency, and the microstructure of the ODS alloy powder can be controlled by adjusting the composition ratio of the raw material powder and the spraying process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of alloy powder feedstock preparation, in particular to a spherical powder preparation method for generating in-situ reaction of dispersively distributed nano-oxide particles in Al or Cr containing multi-principal element alloy powder by thermal spraying-flame quenching technology, which can be widely used in the manufacturing of high-temperature, radiation-resistant, corrosion-resistant and other extreme environment components. BACKGROUND

[0002] High-temperature components used in aerospace, nuclear power, petrochemical power generation and other fields are faced with complex and severe service environments, and their performance and service life are greatly reduced after long-term service. Oxide dispersion strengthened (ODS) alloys can withstand extremely high radiation and high-temperature environments while maintaining good mechanical properties and oxidation resistance. Currently, ODS alloys have been used to manufacture nuclear reactor cladding materials and extreme environment components such as combustion chambers and turbine blades in aircraft engines. However, the preparation quality and efficiency of ODS alloy powder feedstock is a major obstacle to its large-scale application. The mechanical alloying process based on long-period high-energy ball milling is the current more common method for preparing ODS alloy powder, but the ODS alloy powder prepared by this method has quality problems such as uneven distribution of oxides, easy agglomeration of powder, poor sphericity, easy introduction of impurities, and production efficiency problems such as complex process flow. The technologies disclosed in “Nanometer oxide dispersion strengthened high-entropy alloy bonding layer and its preparation method and application (ZL202210349595.6)”, “ODS / GH4169 composite material and its preparation method and formed piece (ZL202311754820.5)”, “Corrosion-resistant oxide dispersion strengthened steel and its preparation method (202311380991.6)” and other technologies all have the problems of oxides not entering the interior of the alloy powder and long process time.

[0003] The documents “New preparation technology of oxide dispersion strengthened ferrite alloy and microstructure research” and “Preparation and characterization of Al2O3 dispersed strengthened copper-tin alloy powder by diffusion method” report a new powder preparation method that uses pre-oxidation instead of mechanical alloying process to introduce oxygen elements into the alloy powder. The patent “Nanometer oxide dispersion type MCrAlY oxidation-resistant coating and its preparation method (202111177182.6)” discloses a method for preparing ODS alloy powder by pre-oxidation process. The alloy powder is laid flat in a high-temperature furnace and heated at a temperature of 600-1000℃ for 5 hours to form a NiCoCrAlYTa multi-principal element alloy powder with nanometer oxide in a dispersed distribution. However, the upper limit of the heating temperature of the high-temperature furnace (≤1000℃) and the process time (>5 hours) seriously limit the production quality and efficiency of the ODS alloy powder. SUMMARY

[0004] The present application aims at the problems of poor powder quality and insufficient production efficiency in the existing ODS alloy powder preparation technology, and provides a method for in-situ preparation of ODS alloy powder by using thermal spraying-flame quenching method. The method is unique in the formation mode of nano-oxides, and uses in-situ oxidation and selective oxidation of Al or Cr in the alloy powder to introduce nano-oxides, and realizes uniform distribution of nano-oxides in the alloy powder by high-speed impact and spatter of the powder at the liquid surface during the spraying process. After spraying, the alloy powder is rapidly cooled in the cooling liquid, and still maintains the spherical shape. The ODS alloy powder obtained by the method contains 2-5 vol.% of in-situ oxides, and has a particle size of 100-500 nm, while the sphericity and flowability of the alloy powder are not affected. The ODS alloy powder prepared by the present application has the advantages of uniform distribution of oxide particles in the powder and high powdering efficiency, and the microstructure control of the ODS alloy powder can be realized by adjusting the composition ratio of the raw material powder and the spraying process.

[0005] A preparation method of in-situ synthesized ODS multi-principal element alloy powder, comprising the following steps:

[0006] Step one: selecting a multi-principal element alloy powder containing Al or Cr, and obtaining an original powder after drying;

[0007] The multi-principal element alloy contains basic elements and residual elements, the basic elements are one or both of Al and Cr, and the percentage of the elements in the multi-principal element alloy is: Al 5-30 at.%, Cr 10-30 at.%; the residual elements are one or more elements of Ni, Fe and Co, and the sum of the residual elements in the multi-principal element alloy is greater than 40 at.%; the particle size range is 50-150 μm;

[0008] Step two: using the original powder in step one as thermal spraying feedstock, and thermal spraying into a cooling liquid for flame quenching;

[0009] The thermal spraying power is 25-40 kW, and the gun distance is 100-450 mm; the powder feeding gas in the thermal spraying is compressed air or a mixture of compressed air and argon; the volume ratio of argon in the powder feeding gas is 0-70 vol.%;

[0010] Step three: collecting the powder sprayed into the cooling liquid in step two, and obtaining a spherical ODS alloy powder after filtration, ultrasonic cleaning, drying and screening.

[0011] The multi-principal element alloy is one or more of AlCoCrFeNi, CoCrFeNi, CoCrNi, NiCoCrAl, NiCrAl, FeCrAl and NiCr.

[0012] The original powder further comprises a modified element X, and the amount of the modified element X is 0-2.0 wt.% of the mass of the original powder; X is one or more of Si, Ti, Mo, V and a rare earth element; and the rare earth element is Y, Ce or La.

[0013] The thermal spraying is ion spraying or flame spraying; the cooling liquid covers a water-based cooling medium or an oil-based cooling medium; the water-based cooling medium is deionized water or brine; and the oil-based cooling medium is mineral oil or kerosene.

[0014] The ODS multi-principal element alloy powder obtained by the method can be applied to high-temperature components or oxidation-resistant coatings under the working conditions of room temperature to 1100 DEG C.

[0015] The substantial features of the present application are:

[0016] In the prior art, ODS alloy powder is prepared by long-time mechanical alloying of alloy powder mixed with nano-oxides, and problems such as uneven distribution of oxides (only on the surface of the powder), easy agglomeration of nano-powder, long ball milling period and poor sphericity exist.

[0017] In view of the above problems, the present application provides a method for in-situ preparation of ODS alloy spherical powder by thermal spraying-flame quenching technology. The present application creatively applies thermal spraying technology to the field of powder manufacturing, uses alloy powder with Al and Cr content of 5-30 at.% as initial feedstock, uses the ultra-high temperature flame (<15000 DEG C) and ultra-fast heating speed (milliseconds) of plasma spraying / flame spraying to greatly improve the pre-oxidation temperature and heating speed, and rapidly generates oxides through in-situ selective oxidation reaction; and uses liquid medium as the spraying matrix to collect the in-situ oxidized powder. The nano-oxides in the ODS alloy powder prepared by the method are more dispersible and controllable, the process is more simple, and the efficiency is also higher.

[0018] In a specific operation, the powder matrix is selected as a multi-component alloy containing Al or Cr (content < 30 at.%), the powder contains dispersedly distributed nano-aluminum oxide or chromium oxide particles, the oxide particle size is in the range of 100-500 nm, and the volume fraction is 2-5 vol.%, so that the high-temperature oxidation rate and the high-temperature softening rate of the powder are reduced by 60% and 90%, respectively; the original powder is sprayed to a liquid medium by using a thermal spraying technology, the nano-particles are synthesized by selective oxidation of Al and Cr elements in the super-high-temperature flame flow, and the dispersed distribution of the nano-oxides in the powder is realized by high-speed impact of the powder on the liquid surface. The prepared ODS alloy powder has better dispersity of the nano-oxides, and the powder maintains high sphericity and fluidity. A key step is to use the multi-component alloy powder containing Al or Cr as the original feedstock, and to spray the original feedstock to the liquid medium by using the thermal spraying technology. In order to realize selective oxidation and efficient collection of the powder, the following key parameters need to be met: the original spraying feedstock is a multi-component alloy powder with Al and Cr content of 5-30 at.%, and the spraying matrix is a liquid medium (distilled water, etc.), which is different from the single main element or coated mixed powder in the current thermal spraying feedstock and the metal spraying matrix.

[0019] The present application has the following advantages:

[0020] (1) The present application provides a spherical ODS alloy powder feedstock and a preparation method. In the preparation process, the oxidation temperature is increased by 1400%, and the required time is reduced by 2900%. The powder maintains good sphericity and fluidity (particle size 15-53 μm, flow rate 18.7 s / 50 g). The present application overcomes the problem that oxides cannot be distributed in the powder in the traditional powder preparation process, so that the number density of the nano-oxides in the powder reaches 2.35 x 10 10 particles / m -3 , and the volume fraction is 5 vol.%. The powder is suitable for the fields of additive manufacturing, thermal spraying, etc.

[0021] (2) The present application uses a multi-component alloy powder containing Al or Cr as the raw material, generates nano-oxides by in-situ oxidation and high affinity of Al and Cr with oxygen during the thermal spraying process, and realizes the dispersed distribution of the nano-oxides in the powder by high-speed impact and spatter of the powder on the liquid surface. There is no report on the preparation of ODS alloy powder by this method. Compared with the current technology of preparing ODS alloy powder by mechanical alloying, the present application has the advantages of more uniform and dispersed distribution of oxides in the powder matrix, high sphericity of the powder, and high powder preparation efficiency.

[0022] (3) The prepared ODS alloy powder is composed of an alloy matrix and nano-oxides dispersedly distributed in the alloy matrix, the nano-oxide composition is controllable (aluminum oxide or chromium oxide), the particle size is 100-500 nm, and the volume fraction is 2-5 vol.%.

[0023] (4) As embodiment 1 of the present application, AlCoCrFeNi alloy powder is used as raw material, and dispersed distribution of nano-aluminum oxide is formed in-situ inside by thermal spraying-flame quenching, with particle size of 100-200 nm and volume fraction of 3.2 vol. %.

[0024] (5) As embodiment 2 of the present application, Al 0.2 CoCrFeNi alloy powder is used as raw material, and dispersed distribution of nano-chromium oxide is formed in-situ inside by thermal spraying-flame quenching, with particle size of 150-500 nm and volume fraction of 3.9 vol. %.

[0025] (6) As embodiment 3 of the present application, CoCrFeNi alloy powder is used as raw material, and dispersed distribution of nano-chromium oxide is formed in-situ inside by thermal spraying-flame quenching, with particle size of 150-500 nm and volume fraction of 4.1 vol. %.

[0026] (7) As embodiment 4 of the present application, NiCrAlY alloy powder is used as raw material, and dispersed distribution of nano-chromium oxide is formed in-situ inside by thermal spraying-flame quenching, with particle size of 150-500 nm and volume fraction of 3.5 vol. %.

[0027] (8) As comparative example 1 of the present application, AlCoCrFeNi alloy powder and nano-aluminum oxide powder are used as raw material, and oxides only exist on the surface of the powder after mechanical alloying for 12 hours, and cannot realize dispersed distribution of oxides inside the powder. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a comparison of surface morphology of powders prepared in embodiment 1 and comparative example 1: wherein, Figure 1 (a) is a morphology photo of ODS alloy powder prepared by thermal spraying-flame quenching method (embodiment 1), Figure 1 (b) is a morphology photo of powder prepared by mechanical alloying method (comparative example 1);

[0029] Figure 2 is a comparison of cross-sectional morphology of powders prepared in embodiment 1 and comparative example 1: wherein, Figure 2 (a), Figure 2 (b) is a morphology photo of ODS alloy powder prepared by thermal spraying-flame quenching method (embodiment 1); Figure 2 (c), Figure 2 (d) is a morphology photo of powder prepared by mechanical alloying method (comparative example 1);

[0030] Figure 3 is a comparison of element distribution results inside powders prepared in embodiment 1 and comparative example 1: wherein, Figure 3(a) is the elemental distribution result of the ODS alloy powder prepared by thermal spraying flame quenching method (Example 1); Figure 3 (b) is the elemental distribution result of the powder prepared by mechanical alloying process (Comparative Example 1);

[0031] Figure 4 is the TEM and EDS result of the internal nano-oxides of the ODS alloy powder in Example 1: wherein, Figure 4 (a), Figure 4 (b) is the FIB sampling area and morphology of the powder; Figure 4 (c), Figure 4 (d) is the HRTEM and SAED image of a single nano-oxide; Figure 4 (e) is the elemental distribution image of the nano-oxide.

[0032] Figure 5 is the high temperature oxidation rate detection comparison chart of the powders prepared in Example 1 and Comparative Example 1;

[0033] Figure 6 is the high temperature softening rate detection comparison chart of the powders prepared in Example 1 and Comparative Example 1. DETAILED DESCRIPTION

[0034] In order to further understand the present application, the present application will be further described below in conjunction with examples, comparative examples and their drawings. It should be pointed out that the following examples are used to introduce the characteristics and advantages of the present application, and do not impose any limitation on the present application.

[0035] Example 1:

[0036] In this example, AlCoCrFeNi alloy powder is used as raw material, and nano-alumina particles are synthesized by selective oxidation of Al during thermal spraying process to realize in-situ preparation of nano-alumina reinforced AlCoCrFeNi alloy powder. The operation steps are as follows:

[0037] Step one: select an equimolar ratio of AlCoCrFeNi alloy powder suitable for thermal spraying, with a composition of 20at.% Al-20at.% Co-20at.% Cr-20at.% Fe-20at.% Ni, and sieve the particle size to 50-150 μm, dry in an 80°C oven for 4h for standby;

[0038] Step two: use the original powder in step one as the plasma spraying-flame quenching feed, and use a self-made device to spray the original powder into distilled water. The process parameters used are: power 32kW, gun distance 200mm, compressed air as powder feeding gas (the same in the following examples);

[0039] Step three: collect the powder sprayed into the cooling liquid in step two, and after filtration, ultrasonic cleaning, drying and screening, the spherical ODS alloy powder with a particle size of 50-150 μm is obtained.

[0040] The powder prepared above is observed using a scanning electron microscope (SEM, JSM7100F, JEOL), and the surface morphology of the powder prepared in Example 1 is shown in Figure 1 (a), which is a regular sphere; and the cross-sectional morphology of the powder is shown in Figure 2 (a) and (b), and the internal oxide particles are dispersed therein, with an average particle size of 132 nm and a volume fraction of 3.2 vol.%;

[0041] The cross-sectional element distribution of the powder prepared above is analyzed using a field emission electron probe microscope (EPMA, JXA-8530F, JEOL), and the results of Example 1 are shown in Figure 3 (a), and the powder of Example 1 is composed of an AlCoCrFeNi matrix and nano-alumina particles;

[0042] The structure and composition of the nano-oxide inside the powder prepared in Example 1 are analyzed using a transmission electron microscope (TEM, G2 F30, Tecnai), and the results are shown in Figure 4 . The spherical nano-oxide particles are composed of alumina and are formed by selective oxidation of Al in the raw material during the plasma spraying and quenching process. When the molten powder is sprayed into the liquid medium, the nano-alumina particles enter the interior of the powder by means of the violent impact and splashing of the powder;

[0043] The mass change of the powder prepared in Example 1 and Comparative Example 1 in the high-temperature atmosphere environment within 100 hours of exposure is recorded using an electronic analytical balance, and the weight gain rate is calculated, and the results are shown in Figure 5 . The oxidation rate of the ODS alloy powder prepared in Example 1 is maintained at <1.25 mg / cm 2 at 900°C, which is decreased by 90% compared with Comparative Example 1. The ODS alloy powder prepared by the present application has obvious advantages in oxidation resistance compared with the prior art;

[0044] The hardness change of the powder prepared in Example 1 and Comparative Example 1 in the high-temperature atmosphere environment within 100 hours of exposure is detected using a microhardness tester (HMV-2T, Shimadzu), and the softening rate is calculated. The loading load of the hardness test is 100 g (HV0.1), the loading time is 15 s, and the average value is obtained by repeating the measurement multiple times (>10 times), and the results are shown in Figure 6The ODS alloy powder prepared in Example 1 has a Vickers hardness of >330HV at 900℃, and a softening rate of <5% within 100 hours. Compared with the prior art, the ODS alloy powder prepared in the application has obvious advantages in softening resistance. The powder prepared in the application can meet the requirements of high-temperature components or high-temperature coatings in high-temperature oxidation performance, softening resistance and sphericity.

[0045] Example 2:

[0046] In this example, Al 0.2 CoCrFeNi alloy powder is used as raw material, and the composition is 5at.% Al-23.75at.% Co-23.75at.% Cr-23.75at.% Fe-23.75at.% Ni. Nano-chromium oxide particles are introduced by selective oxidation of Cr during thermal spraying, so as to realize nano-chromium oxide reinforced Al 0.2 The in-situ preparation of CoCrFeNi alloy powder is as follows:

[0047] Step 1: select Al 0.2 CoCrFeNi alloy powder with a particle size of 50-150μm is dried in an 80℃ oven for 4h for standby;

[0048] Step 2: use the raw powder in Step 1 as the thermal spraying-flame quenching feed, and use a self-made device to spray the raw powder into distilled water. The process parameters used are: power 30kW, and the other parameters are the same as those in Example 1;

[0049] Step 3: collect the powder sprayed into the cooling liquid in Step 2, and after filtration, ultrasonic cleaning, drying and screening, spherical ODS alloy powder with a particle size of 50-150μm is obtained.

[0050] In Example 2, the powder prepared from an alloy with low Al and high Cr content is regular spherical, and the surface morphology is similar to that of Figure 1 (a); the chromium oxide particles dispersed in the powder have a particle size range of 150-500nm, an average particle size of 360nm, and a volume fraction of 3.7vol.%; the cross-sectional morphology is similar to that of Figure 2 (a)(b); the powder is composed of CoCrFeNi matrix and dispersed nano-chromium oxide particles, and the element distribution results are similar to those of Figure 3 (a).

[0051] Example 3:

[0052] The present embodiment uses CoCrFeNi alloy powder as raw material, the composition is 25at.% Co-25at.% Cr-25at.% Fe-25at.% Ni, and the in-situ preparation of the nano-chromium oxide reinforced CoCrFeNi alloy powder is realized by introducing nano-chromium oxide particles by selective oxidation of Cr in the thermal spraying process. The operation steps are as follows:

[0053] Step one: select the CoCrFeNi alloy powder suitable for thermal spraying, and sieve the particle size to 50-150 μm, dry in the 80℃ oven for 4h for standby;

[0054] Step two: use the self-made device to spray the original powder into distilled water by taking the original powder in step one as the plasma spraying-flame quench feeding. The process parameters used are: power 28kW, and the rest of the parameters are the same as example 1;

[0055] Step three: collect the powder sprayed into the cooling liquid in step two, and after filtration, ultrasonic cleaning, drying and screening, the spherical ODS alloy powder with particle size of 50-150 μm is obtained.

[0056] The powder prepared in example 3 is regular spherical, and the surface morphology is similar to that of Figure 1 (a); the chromium oxide particles are dispersedly distributed in the powder, the particle size range is 150-500 nm, the average particle size is 409 nm, the volume fraction is 4.2vol.%, and the cross-sectional morphology is similar to that of Figure 2 (a)(b); the in-situ reaction product of example 3 is nano-chromium oxide particles; and the element distribution results in the powder are similar to those of Figure 3 (a), which is composed of CoCrFeNi alloy matrix and chromium oxide nanoparticles.

[0057] Example 4:

[0058] The present embodiment is based on NiCrAlY powder raw material, the composition is Ni balance-22at.% Cr-10at.% Al-0.5at.% Y, and the in-situ preparation of ODS powder feed is realized by introducing nano-chromium oxide particles by selective oxidation of Cr in the thermal spraying-flame quenching process. The operation steps are as follows:

[0059] Step one: select the NiCrAlY alloy powder suitable for thermal spraying, and sieve the particle size to 50-150 μm, dry in the 80℃ oven for 4h for standby;

[0060] Step two: use the self-made device to spray the original powder into distilled water by taking the original powder in step one as the plasma spraying-flame quench feeding. The process parameters used are: power 30kW, and the rest of the parameters are the same as example 2;

[0061] Step three: collect the powder sprayed into the cooling liquid in step two, and after filtration, ultrasonic cleaning, drying and screening, spherical ODS alloy powder with a particle size of 50-150 μm is obtained.

[0062] The powder prepared in Example 4 is regular spherical, and the surface morphology is similar to Figure 1 (a); the powder is composed of a dispersed distribution of chromium oxide particles in the interior, the particle size range of the particles is 200-500 nm, the average particle size of the particles is 449 nm, the volume fraction is 3.5 vol.%, and the cross-sectional morphology is similar to Figure 2 (a) (b); the powder is composed of a NiCrAl alloy matrix and nano-chromium oxide particles in the interior, and the element distribution results are similar to Figure 3 (a).

[0063] Comparative Example 1:

[0064] In order to illustrate the organizational characteristics and process advantages of the ODS alloy powder prepared in the present application, the present comparative example is set as a reference. The AlCoCrFeNi alloy powder and nano-alumina are used as raw materials in the present comparative example, and the composition is 20 at.% Al-20 at.% Co-20 at.% Cr-20 at.% Fe-20 at.% Ni. The ODS alloy powder is prepared by mechanical alloying, and the preparation method of Comparative Example 1 is different from that of Examples 1, 2, 3 and 4 in that the introduction method of the oxide is exogenous addition instead of in-situ generation. The operation steps are as follows:

[0065] Step one: select α-alumina powder with a particle size of 50 nm and AlCoCrFeNi alloy powder, and sieve the particle size to 50-150 μm, and dry in a 80°C oven for 4 h for standby;

[0066] Step two: use a planetary ball mill to mechanically alloy the AlCoCrFeNi and nano-alumina raw material powder, and the parameters are: 5 wt.% alumina, ball-to-material ratio 20:1, rotation speed 400 r / min, and time 12 h.

[0067] Step three: collect the powder after ball milling in step two, and sieve to obtain alloy powder with a particle size of 50-150 μm.

[0068] The surface morphology and cross-sectional morphology of the powder prepared in Comparative Example 1 are shown in Figure 1 (b) and Figure 2 (c) (d), and the oxide only exists on the surface of the powder and cannot be uniformly distributed in the interior of the powder; the element distribution results in the interior of the powder are shown in Figure 3 (b), and no oxide is observed in the interior of the powder.

[0069] The detection results of the comparative example show that the oxides in the powder prepared by using the current technology (mechanical alloying) usually exist only on the surface of the powder. This is because the physical and chemical environment (temperature, pressure, atmosphere and other factors) of mechanical alloying causes the lack of sufficient oxygen diffusion in the interior of the powder, thereby limiting the formation and dispersion distribution of oxides in the interior of the powder.

[0070] The comparison of examples 1-4 and comparative example 1 shows that the present application can efficiently realize the dispersion distribution of nano-oxides in the interior of the alloy powder.

[0071] The thermal spraying-flame quenching technology provided by the present application has the characteristics of simple process, high powder preparation efficiency and low cost. The technology uses alloy powder containing Al or Cr as raw material, realizes in-situ formation of oxides by selective oxidation reaction of the powder in the thermal spraying process, and makes the oxides more uniformly distributed in the powder by high-speed impact and splashing of the powder on the liquid surface, so as to realize the structure regulation of ODS alloy powder by adjusting the composition ratio of the raw material and the spraying process. The ODS alloy powder prepared by the present application has uniformly distributed nano-oxides in the interior, the content of which is 2-5 vol.%, the particle size is 100-500 nm, and the powder has good sphericity and fluidity.

[0072] The above-described examples and their accompanying drawings have made a detailed introduction to the present application. It should be pointed out that the above-described examples are used to introduce the characteristics and advantages of the present application, and do not make any limitation requirements on the present application, but it is necessary to point out that all the similar ways of modification, supplement, replacement and the like made within the principle range of the present application should be included in the protection scope of the present application.

[0073] The remaining matters of the present application are the known technology.

Claims

1. A method for in-situ synthesis of ODS multi-principal element alloy powders, characterized by, The method comprises the following steps: Step one: selecting Al or Cr containing multi-principal element alloy powder, drying to obtain original powder; The multi-principal element alloy contains basic elements and residual elements, the basic elements are one or both of Al and Cr, the percentage of the elements in the multi-principal element alloy is: Al 5-30 at.%, Cr 10-30 at.%; the residual elements are one or more of Ni, Fe and Co, the sum of the residual elements in the multi-principal element alloy is greater than 40 at.%, the particle size range is 50-150 μm; Step two: using the original powder in step one as thermal spraying feedstock, thermal spraying into cooling liquid for flame quenching; The thermal spraying power is 25-40 kW, the gun distance is 100-450 mm; the powder feeding gas in thermal spraying is compressed air or a mixture of compressed air and argon; the argon volume ratio in the powder feeding gas is 0-70 vol.%; The cooling liquid is water-based cooling medium or oil-based cooling medium; Step three: collecting the powder sprayed into the cooling liquid in step two, filtering, ultrasonic cleaning, drying and screening to obtain spherical ODS alloy powder.

2. The method of claim 1, wherein the in-situ synthesis of ODS multi-principal element alloy powder is characterized by, The multi-principal element alloy is one or more of AlCoCrFeNi, CoCrFeNi, CoCrNi, NiCoCrAl, NiCrAl, FeCrAl and NiCr.

3. The method of claim 1, wherein the in-situ synthesis of ODS multi-principal element alloy powder is characterized by, The original powder further contains modifying element X, the adding amount of the modifying element is 0-2.0 wt.% of the mass of the original powder; X is one or more of Si, Ti, Mo, V and rare earth elements; the rare earth elements are Y, Ce or La.

4. The method of claim 1, wherein the in-situ synthesis of ODS multi-principal element alloy powder is characterized by, The thermal spraying is ion spraying or flame spraying; the water-based cooling medium is deionized water or brine, and the oil-based cooling medium is mineral oil or kerosene.

5. Use of the ODS multi-principal element alloy powder obtained by the method of claim 1, characterized in that, The application is applied to raw materials of high temperature components or oxidation resistant coatings under room temperature-1100℃ working conditions.

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