Nickel alloy powder and preparation method and application thereof

Abstract

The invention relates to the technical field of additive manufacturing, and particularly provides nickel alloy powder and a preparation method and application thereof. Raw materials of the high-strength and high-toughness Ni-Cr-Co-C-C alloy comprise 50%-85% of Ni, 10%-20% of Cr, 5%-12% of Co, 3%-8% of Mo, 0.5%-2.5% of Al, 0.3%-1.5% of Ti, smaller than or equal to 0.08% of C, 0.06%-0.08% of nano carbide particles, 0.3%-0.5% of Y2O3-Ni core-shell structure particles, 0.05%-0.5% of rare earth elements and the balance inevitable impurities. The nano carbide particles are at least one of TiC, WC and SiC; the rare earth element is at least one of Ce and La. Compared with a traditional atomization method, nano-particle modification and a pulse process are adopted, and the problem of the closed hole defect of the nickel-based high-temperature alloy powder is systematically solved.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and particularly to a nickel alloy powder, a preparation method thereof and an application thereof. Background Art

[0002] In the process of preparing nickel-based superalloy powder by traditional atomization method, inert gas is easily wrapped inside the droplets to form closed-pore hollow powder. During the additive manufacturing process, due to high-temperature melting, the gas inside the closed pores expands, forming micropore defects, which significantly reduce the density, high-temperature fatigue strength and creep resistance of the components. Research shows that when the hollow powder rate exceeds 5%, the fatigue life of key components such as turbine disks decreases by more than 30%.

[0003] Although the existing process can partially reduce the hollow powder by adjusting the atomization pressure, melt temperature, etc., it cannot completely eliminate the closed-pore defects. The vacuum degassing process can only remove the gas inside the open-pore hollow powder and is ineffective for closed pores. Introducing nanoparticles for grain refinement can improve the problem to a certain extent, but excessive addition will lead to deteriorated fluidity.

[0004] Based on this, there is an urgent need to develop a preparation method of nickel-based alloy powder with the ability to control closed-pore defects to meet the additive manufacturing requirements of high-reliability components. Summary of the Invention

[0005] In view of this, the present invention provides a nickel alloy powder, a preparation method thereof and an application thereof.

[0006] The technical solution of the present invention is realized as follows: The present invention provides a nickel alloy powder, which includes, by weight percentage:

[0007] Ni 50-85%

[0008] Cr 10-20%

[0009] Co 5-12%

[0010] Mo 3-8%

[0011] Al 0.5-2.5%

[0012] Ti 0.3-1.5%

[0013] C ≤ 0.08%

[0014] Nanocarbonide particles 0.06-0.0,8%

[0015] Y2O3@Ni core-shell structure particles 0.3-0.5%

[0016] Rare earth elements 0.05-0.5%

[0017] The balance is unavoidable impurities;

[0018] The nano carbide particles are at least one of TiC, WC and SiC; the rare earth element is at least one of Ce and La.

[0019] In the above embodiment, by adding nanocarbides as the heterogeneous nucleation core and combining with Y2O3@Ni core-shell particles, the grains can be refined and grain boundary segregation can be suppressed, reducing the formation of closed pores during solidification. The rare earth elements Ce / La strengthen the grain boundaries, reduce the risk of TCP phase formation, improve high-temperature oxidation resistance, and reduce gas adsorption.

[0020] In some embodiments, the powder has a particle size of 15-53 μm, a D50 of 30-40 μm, a sphericity of ≥95%, a powder oxygen content of ≤200 ppm, a hollow powder rate of ≤5%, and a flowability of 33-35 s / 50 g.

[0021] In the above embodiment, the gas inside the droplets is forced to be discharged through mixed gas atomization and pulse supercharging, thereby reducing the hollow powder rate from 15-20% in the traditional process to ≤5%. Vacuum rotary degassing and inert gas packaging reduce the oxygen content from 300-500ppm to ≤200ppm, thereby avoiding powder storage contamination.

[0022] In some embodiments, the surface of the nanocarbide particles is coated with a nickel shell layer, the particle size of the nanocarbide particles is 10-100 nm, and the shell layer thickness is 5-10 nm.

[0023] In some embodiments, the Y2O3 core layer particle size of the core-shell structure particles is 50-100 nm, and the preparation method of the core-shell structure particles includes: mixing Y2O3 particles with nickel chloride solution, adding sodium borohydride and reacting at pH = 10 for 30 minutes, centrifuging and washing, and then vacuum drying.

[0024] In the above embodiments, the nickel shell structure can reduce the agglomeration of carbides, enhance interface bonding, and avoid density segregation during cladding.

[0025] In a second aspect, the present invention further provides a method for preparing the nickel alloy powder, comprising the following steps:

[0026] Step 1: Melt Ni, Cr, Co and Mo at 1400-1500℃, vacuum degree ≤10 -1 Pa, argon partial pressure 5-10kPa, keep warm for 20-30min, then raise the temperature to 1550-1600℃, add Al, Ti, nano carbide particles and Y2O3@Ni core-shell structure particles, and keep warm for 10-40min;

[0027] Step 2: Using a mixed gas of nitrogen and argon, in the atomization tower, atomize the molten metal in Step 1 with an atomization pressure of 3.0 - 3.5 MPa to obtain nickel alloy powder;

[0028] Step 3: Degas the obtained nickel alloy powder in a vacuum rotary furnace for 30 - 60 min.

[0029] In the above embodiments, melting Al, Ti and other metals separately can reduce oxidation and volatilization. Using a mixed gas of nitrogen and argon for atomization can reduce the rate of hollow powder.

[0030] In some embodiments, the ratio of nitrogen to argon is (85 - 95):(15 - 5).

[0031] The specific heat capacity of nitrogen is significantly higher than that of argon, which can accelerate the cooling and solidification of molten droplets, shorten the residence time of gas inside the droplets, and reduce the formation of closed-cell hollow powder. The surface tension of argon atomized powder is greater, which promotes the spheroidization of droplets, forming high sphericity and smooth surface. The small addition of argon in the mixed gas can make up for the possible surface roughness problem caused by pure nitrogen atomization, and there are fewer satellite particles in argon atomized powder. Argon does not react with the molten metal at high temperature, avoiding nitride impurities that may be caused by nitrogen. The proportion of argon in the mixed gas being 15 - 5% can reduce the chemical activity risk of nitrogen at high temperature, maintain the low oxygen content of the powder. The cost of nitrogen is only 1 / 3 - 1 / 2 of that of argon. Mixing them can reduce the process cost. At the same time, by dominating the atomization process with a high proportion of nitrogen (85 - 95%), the economy is improved. The high cooling rate of nitrogen promotes the reduction of dendrite spacing, refines grains, and improves the material strength. Nitrogen may absorb trace nitrogen elements through the melt, promoting the formation of nano-precipitates such as TiN, thereby enhancing the high-temperature resistance of the alloy.

[0032] In some embodiments, during the atomization process, a 10 MPa high-pressure pulse is also included.

[0033] Pulse boosting (10 MPa) destroys the solidified layer on the surface of the droplet through a high-pressure impact in an extremely short time, and forcibly discharges the inert gas wrapped inside the droplet. The traditional continuous atomization pressure (such as 3 - 5 MPa) is difficult to penetrate the solidified droplet surface, while the pulsed high pressure can periodically interrupt the solidification process and promote the escape of gas. The shear force on the droplet under pulsed pressure increases significantly, breaking large droplet particles into finer and more uniform particles. The vibration effect of the high-pressure pulse reduces the agglomeration of nano-particles and improves the dispersibility. The timing for introducing the above high-pressure pulse is to start the pulse when the oxygen content in the atomization chamber ≥ 3%, the pulse frequency is 10 - 20 Hz, and the duty cycle is 20 - 40%.

[0034] In some embodiments, the inlet hot air temperature of the atomization tower is 100 - 150 °C, the outlet temperature ≤ 30 °C, and the cooling rate ≥ 10 5 °C / s.

[0035] The inlet temperature prevents premature solidification on the droplet surface, allowing the internal gas to escape during the initial stage of cooling; the ultra-fast cooling shortens the gas residence time and reduces TIP. After atomization, the powder is degassed in vacuum to further reduce the residual argon content. The cooling rate shortens the diffusion distance of solute atoms to the nanoscale, eliminating dendritic segregation.

[0036] In some embodiments, Al, Ti, nanocarbide particles, and Y2O3@Ni core-shell structure particles are all fed by wrapping with aluminum foil.

[0037] Feeding by wrapping with aluminum foil protects the active elements and reduces oxide inclusions in the molten pool.

[0038] The present invention also provides an application of the above nickel alloy powder for additive manufacturing to form a nickel alloy workpiece.

[0039] The present invention has the following beneficial effects compared with the prior art:

[0040] Compared with the traditional atomization method, the present invention adopts nanoparticle modification and pulse process, systematically solving the problem of closed pore defects in nickel-based superalloy powders. Nanocarbides promote heterogeneous nucleation in the molten pool, reducing the dendrite spacing to the micron scale and inhibiting the formation of closed pores caused by solidification shrinkage. The Y2O3 core blocks grain boundary segregation, and the Ni shell layer enhances the particle-matrix interface bonding, reducing gas adsorption during solidification; rare earth elements preferentially combine with oxygen / sulfur to form stable compounds, reducing the gas solubility in the molten pool and reducing the generation of TIP. Specific Embodiments

[0041] Next, in combination with the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0042] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0043] It should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0044] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the embodiments of the present invention belong. If the definitions stated in this part are contrary to or otherwise inconsistent with the definitions stated in the patents, patent applications, published patent applications, and other publications incorporated herein by reference, the definitions listed in this part shall prevail over the definitions incorporated herein by reference.

[0046] Unless otherwise specified, the methods used in the following embodiments are all conventional methods. The materials, reagents, and instruments used, unless otherwise specified, are all conventional materials, reagents, and instruments in the art, and those skilled in the art can obtain them through commercial channels.

[0047] When an equivalent, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper limit preferred values and lower limit preferred values, this should be understood to specifically disclose all ranges formed by any pairing of any range upper limit or preferred value with any range lower limit or preferred value, regardless of whether the range is separately disclosed. For example, when the range "1 to 5" is disclosed, the described range should be interpreted to include ranges "1 to 4", "1 to 3", "1 to 2", "1 to 2 and 4 to 5", "1 to 3 and 5", etc. When a numerical range is described herein, unless otherwise stated, the range is intended to include its end values and all integers and fractions within the range. In the specification and claims of the present application, range limitations can be combined and / or interchanged, and if not otherwise stated, these ranges include all sub-ranges contained therein.

[0048] Example 1

[0049] This example provides a method for preparing nickel alloy powder.

[0050] Raw material ratio:

[0051] Ni - 62%, Cr - 18%, Co - 8%, Mo - 5%, Al - 2.0%, Ti - 1.0%, TiC@Ni nanoparticles (particle size 50 nm, shell thickness 8 nm) - 0.07%, Y2O3@Ni core - shell particles (Y2O3 core 80 nm) - 0.4%, Ce - 0.2%

[0052] It includes the following steps:

[0053] Smelting: Ni, Cr, Co, Mo are smelted at 1450 °C (vacuum degree 5×10 -2 Pa, argon partial pressure 8 kPa) for 25 min, then heated to 1580 °C and Al, Ti and TiC@Ni nanoparticles and Y2O3@Ni core - shell particles (wrapped with aluminum foil) are added, and kept warm for 30 min;

[0054] Atomization: The mixing ratio of nitrogen / argon is 90:10, the atomization pressure is 3.2 MPa, and a high - voltage pulse of 10 MPa is applied (started when the oxygen content in the atomization chamber is ≥3%, frequency 15 Hz, duty cycle 30%);

[0055] Cooling: The inlet temperature of the atomization tower is 130 °C, the outlet temperature is 25 °C, and the cooling rate is 1.1×10 5 °C / s;

[0056] Post - treatment: Vacuum rotary degassing for 45 min and then screening (15 - 53 μm), and finally encapsulated with argon.

[0057] Example 2

[0058] This example provides a method for preparing nickel - based alloy powder.

[0059] Raw material ratio:

[0060] Ni - 62%, Cr - 18%, Co - 8%, Mo - 5%, Al - 2.0%, Ti - 1.0%, TiC@Ni nanoparticles (particle size 50 nm, shell thickness 8 nm) - 0.07%, Y2O3@Ni core - shell particles (Y2O3 core 80 nm) - 0.4%, Ce - 0.2%

[0061] It includes the following steps:

[0062] Smelting: Ni, Cr, Co, Mo are smelted at 1450 °C (vacuum degree 5×10 -2 Pa, argon partial pressure 8 kPa) for 25 min, then heated to 1580 °C and Al, Ti and TiC@Ni nanoparticles and Y2O3@Ni core - shell particles (wrapped with aluminum foil) are added, and kept warm for 30 min;

[0063] Atomization: The mixing ratio of nitrogen / argon is 95:5, the atomization pressure is 3.5 MPa, and a high-voltage pulse of 10 MPa is applied (started when the oxygen content in the atomization chamber is ≥ 3%, the frequency is 15 Hz, and the duty cycle is 30%);

[0064] Cooling: The inlet temperature of the atomization tower is 130 °C, the outlet temperature is 25 °C, and the cooling rate is 1.1×10 5 °C / s;

[0065] Post-treatment: Vacuum rotary degassing for 45 min and then screening (15 - 53 μm), and finally encapsulation with argon.

[0066] Example 3

[0067] This example provides a method for preparing nickel alloy powder.

[0068] Raw material ratio:

[0069] Ni - 62%, Cr - 18%, Co - 8%, Mo - 5%, Al - 2.0%, Ti - 1.0%, TiC@Ni nanoparticles (particle size 50 nm, shell thickness 8 nm) - 0.07%, Y2O3@Ni core-shell particles (Y2O3 core 80 nm) - 0.5%, La - 0.3%, Ce - 0.2%

[0070] It includes the following steps:

[0071] Smelting: Ni, Cr, Co, and Mo are smelted at 1450 °C (vacuum degree 5×10 -2 Pa, argon partial pressure 8 kPa) for 25 min, then heated to 1580 °C and Al, Ti, TiC@Ni nanoparticles, and Y2O3@Ni core-shell particles (wrapped in aluminum foil) are added, and kept warm for 30 min;

[0072] Atomization: The mixing ratio of nitrogen / argon is 90:10, the atomization pressure is 3.2 MPa, and a high-voltage pulse of 10 MPa is applied (started when the oxygen content in the atomization chamber is ≥ 3%, the frequency is 15 Hz, and the duty cycle is 30%);

[0073] Cooling: The inlet temperature of the atomization tower is 130 °C, the outlet temperature is 25 °C, and the cooling rate is 1.1×10 5 °C / s;

[0074] Post-treatment: Vacuum rotary degassing for 45 min and then screening (15 - 53 μm), and finally encapsulation with argon.

[0075] Comparative Example 1

[0076] This comparative example provides a method for preparing nickel alloy powder, and its raw materials omit nanoparticles.

[0077] Raw material ratio:

[0078] Ni - 62%, Cr - 18%, Co - 8%, Mo - 5%, Al - 2.0%, Ti - 1.0%, Ce - 0.2%

[0079] Includes the following steps:

[0080] Smelting: Ni, Cr, Co, Mo are smelted at 1450 °C (vacuum degree 5×10 -2 Pa, argon partial pressure 8 kPa) for 25 min, then heated to 1580 °C and Al, Ti (wrapped in aluminum foil) are added, and kept warm for 30 min;

[0081] Atomization: The nitrogen / argon mixing ratio is 90:10, the atomization pressure is 3.2 MPa, and a 10 MPa high - voltage pulse is applied (started when the oxygen content in the atomization chamber ≥ 3%, frequency 15 Hz, duty cycle 30%);

[0082] Cooling: The inlet temperature of the atomization tower is 130 °C, the outlet is 25 °C, and the cooling rate is 1.1×10 5 °C / s;

[0083] Post - treatment: Vacuum rotary degassing for 45 min and then sieving (15 - 53 μm), and finally argon encapsulation.

[0084] Comparative Example 2

[0085] This comparative example provides a method for preparing nickel - based alloy powder, in which pure argon is used for atomization.

[0086] Raw material ratio:

[0087] Ni - 62%, Cr - 18%, Co - 8%, Mo - 5%, Al - 2.0%, Ti - 1.0%, TiC@Ni nanoparticles (particle size 50 nm, shell thickness 8 nm) - 0.07%, Y2O3@Ni core - shell particles (Y2O3 core 80 nm) - 0.4%, Ce - 0.2%

[0088] Includes the following steps:

[0089] Smelting: Ni, Cr, Co, Mo are smelted at 1450 °C (vacuum degree 5×10 -2 Pa, argon partial pressure 8 kPa) for 25 min, then heated to 1580 °C and Al, Ti, TiC@Ni nanoparticles and Y2O3@Ni core - shell particles (wrapped in aluminum foil) are added, and kept warm for 30 min;

[0090] Atomization: Argon, atomization pressure 3.2 MPa, and a 10 MPa high - voltage pulse is applied (started when the oxygen content in the atomization chamber ≥ 3%, frequency 15 Hz, duty cycle 30%);

[0091] Cooling: The inlet temperature of the atomization tower is 130 °C, the outlet temperature is 25 °C, and the cooling rate is 1.1×10 5 °C / s;

[0092] Post-treatment: Vacuum rotary degassing for 45 min and then sieving (15 - 53 μm), and finally encapsulation with argon.

[0093] Comparative Example 3

[0094] This comparative example provides a method for preparing nickel alloy powder without high-voltage pulse operation.

[0095] Raw material ratio:

[0096] Ni - 62%, Cr - 18%, Co - 8%, Mo - 5%, Al - 2.0%, Ti - 1.0%, TiC@Ni nanoparticles (particle size 50 nm, shell thickness 8 nm) - 0.07%, Y2O3@Ni core-shell particles (Y2O3 core 80 nm) - 0.4%, Ce - 0.2%

[0097] The method includes the following steps:

[0098] Smelting: Ni, Cr, Co, and Mo are smelted at 1450 °C (vacuum degree 5×10 -2 Pa, argon partial pressure 8 kPa) for 25 min, then heated to 1580 °C and Al, Ti, TiC@Ni nanoparticles, and Y2O3@Ni core-shell particles (wrapped in aluminum foil) are added, and kept warm for 30 min;

[0099] Atomization: The nitrogen / argon mixing ratio is 90:10, and the atomization pressure is 3.2 MPa;

[0100] Cooling: The inlet temperature of the atomization tower is 130 °C, the outlet temperature is 25 °C, and the cooling rate is 1.1×10 5 °C / s;

[0101] Post-treatment: Vacuum rotary degassing for 45 min and then sieving (15 - 53 μm), and finally encapsulation with argon.

[0102] The hollow powder ratio of the nickel alloy powders prepared in the above different examples and comparative examples is detected respectively. The detection method uses the metallographic method. After embedding - grinding and polishing, microscopic observation is carried out, and the proportion of particles with closed pore diameter ≤2 μm is counted.

[0103] At the same time, the oxygen content is also measured: The detection is carried out by the pulse heating infrared absorption method.

[0104] The sphericity is calculated by laser particle size analysis and SEM image analysis.

[0105] Meanwhile, the above nickel alloy powder was loaded into a sheath and hot extrusion forged at 1200 °C and 150 MPa to obtain bars, and tensile tests, constant stress creep experiments, dynamic creep experiments, and cyclic creep experiments were carried out on the bars.

[0106] The following data results were obtained as shown in the table below:

[0107]

[0108] In Examples 1-3, through the mixed atomization of nitrogen and argon and a high-pressure pulse of 10 MPa, the hollow powder rate was significantly reduced. The high specific heat capacity of nitrogen accelerated cooling and shortened the gas residence time. Combined with inert gas encapsulation, powder oxidation pollution was reduced compared with the traditional process.

[0109] The nano-carbide served as a heterogeneous nucleation core, refining the grain size from the traditional 45 μm to 12 μm and improving the tensile strength.

[0110] The core-shell nanoparticles inhibited grain boundary segregation through the interface pinning effect, improving the high-temperature mechanical properties.

[0111] The purification effect of rare earth elements on grain boundaries reduced the precipitation of TCP phase and increased the elongation after fracture.

[0112] In Examples 1-3, nitrogen / argon mixed atomization was adopted, and the sphericity was increased by dynamically regulating the surface tension and cooling rate.

[0113] The results of the constant stress creep experiment are as shown in the table below:

[0114]

[0115]

[0116] In Examples 1-3, through nitrogen / argon mixed atomization (accelerated cooling) and high-pressure pulse (reduced oxygen residue), the steady-state creep rate was significantly reduced (3-5 times higher than that of the comparative example), and the fracture time was extended to 150-384 hours.

[0117] Nanoparticles (TiC@Ni, Y2O3@Ni): promoted the uniform precipitation of γ' phase and inhibited grain boundary slip (the grain size of Example 1 was ASTM 11-13 grade, while that of Comparative Example 1 was only ASTM 6-8 grade).

[0118] In Comparative Example 1, due to the absence of nanoparticles, the grains were coarsened (from 45 μm to 12 μm), and the creep resistance decreased by 70%;

[0119] In Comparative Example 3, without a high-pressure pulse, the oxygen content reached 280 ppm, causing grain boundary oxidation cracks and accelerating creep fracture.

[0120] The results of the dynamic creep experiment are as shown in the table below:

[0121]

[0122] In Examples 1-3, due to the purification of grain boundaries by rare earth elements (Ce / La), the dynamic creep plastic deformation amount ≤ 0.25%, which is 50% lower than that of the comparative example.

[0123] Under sawtooth wave loading, the dislocation tangling density in Example 1 is high, suppressing strain localization.

[0124] In Comparative Example 2, due to the insufficient cooling rate of pure argon atomization, the volume fraction of TCP phase (σ phase) reaches 5%, accelerating dynamic creep failure.

[0125] The results of the cyclic creep experiment are shown in the following table:

[0126] Don't Temperature / stress amplitude Number of cycles (Nf) Creep life attenuation rate (%) Fracture surface characteristics Example 1 700°C / 300 MPa 35,000 ≤10 Dimples + a small amount of intergranular cracks Example 2 750°C / 400 MPa 28,000 15 Mixed fracture (transgranular + intergranular) Example 3 800°C / 500 MPa 18,000 25 Mainly intergranular fracture Comparative example 1 700°C / 300 MPa 10,000 50 Intergranular brittle fracture Comparative example 2 750°C / 400 MPa 7,500 60 Cleavage fracture induced by TCP phase Comparative example 3 800°C / 500 MPa 5,200 75 Oxidation holes are connected in series to form macroscopic cracks

[0127] In Example 1, the number of cycles reaches 35,000 at 700 °C / 300 MPa (only 10,000 in Comparative Example 1), attributed to the pinning of dislocations by nano-carbides and the inhibition of dynamic recrystallization.

[0128] The fracture surface of the example is mainly dimpled, while that of the comparative example is generally intergranular brittle fracture.

[0129] In Comparative Example 3, due to the absence of high-voltage pulses, the oxygen content is 280 ppm, and the volume fraction of oxidation pores reaches 0.78% during cyclic creep, with a life decay rate of 75%.

[0130] The above is only the preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A nickel alloy powder, characterized in that, By weight percentage, it includes the following components: Ni 50 - 85% Cr 10-20％ Co 5 - 12% Mo 3 - 8% Al 0.5-2.5％ Ti 0.3 - 1.5% C≤0.08％ Nanocarbonide particles 0.06 - 0.08% Y2O3@Ni core - shell structure particles 0.3 - 0.5% Rare earth elements 0.05 - 0.5% The balance is inevitable impurities; The nanocarbonide particles are at least one of TiC, WC, and SiC; the rare earth elements are at least one of Ce and La.

2. The nickel alloy powder according to claim 1, characterized in that, The particle size of the powder is 15 - 53μm, D50 is 30 - 40μm, the sphericity ≥ 95%, the oxygen content of the powder ≤ 200ppm, the hollow powder rate ≤ 5%, and the fluidity is 33 - 35s / 50g.

3. The nickel alloy powder according to claim 1, characterized in that, The surface of the nanocarbonide particles is coated with a nickel shell layer. The particle size of the nanocarbonide particles is 10 - 100nm, and the shell layer thickness is 5 - 10nm.

4. The nickel alloy powder according to claim 3, characterized in that, The particle size of the core layer Y2O3 of the core - shell structure particles is 50 - 100nm. The preparation method of the core - shell structure particles includes: mixing Y2O3 particles with nickel chloride solution, adding sodium borohydride and reacting for 30 minutes under the condition of pH = 10, followed by centrifugal washing and vacuum drying.

5. The method for preparing the nickel alloy powder according to any one of claims 1-4, characterized in that, It includes the following steps: Step 1: Melting Ni, Cr, Co, Mo at 1400 - 1500°C, with the vacuum degree ≤ 10 - 1Pa and the argon partial pressure 5 - 10kPa, holding for 20 - 30min, then heating to 1550 - 1600°C, adding Al, Ti, nanocarbonide particles and Y2O3@Ni core - shell structure particles, and holding for 10 - 40min; Step 2: Using a mixed gas of nitrogen and argon, in an atomization tower, atomizing the metal melted in Step 1 at an atomization pressure of 3.0 - 3.5MPa to obtain nickel alloy powder; Step 3: Degassing the obtained nickel alloy powder in a vacuum rotary furnace for 30 - 60min.

6. The preparation method according to claim 5, characterized in that, In Step 2, the ratio of nitrogen to argon is (85 - 95):(15 - 5).

7. The preparation method according to claim 5, characterized in that In Step 2, during the atomization process, a 10MPa high - voltage pulse is also included.

8. The preparation method according to claim 5, characterized in that, In Step 2, the inlet hot air temperature of the atomization tower is 100 - 150 °C, the outlet temperature ≤ 30 °C, and the cooling rate ≥ 10 5 °C / s.

9. The preparation method according to claim 5, characterized in that, In Step 1, Al, Ti, nanocarbonide particles and Y2O3@Ni core - shell structure particles are all fed by wrapping with aluminum foil.

10. Use of the nickel alloy powder according to any one of claims 1 to 4, characterized in that, It is used for additive manufacturing to form nickel alloy workpieces.

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