Nickel-based superalloy powder and preparation method and application thereof, nickel-based superalloy and preparation method and application thereof

Abstract

The invention provides nickel-based superalloy powder and a preparation method and application thereof, nickel-based superalloy and a preparation method and application thereof, and relates to the technical field of alloys. The preparation method comprises the following steps: smelting a nickel-based high-temperature alloy raw material to obtain alloy liquid; and the alloy liquid is atomized and crushed, and the nickel-based high-temperature alloy powder is obtained. Compared with traditional nickel-based superalloy preparation, aluminum nitride and titanium nitride raw materials are added in the nickel-based superalloy powder preparation process, aluminum nitride and titanium nitride are separated out in the alloy powder preparation process to form a strengthening phase, and the tensile strength and the elongation at break of the nickel-based superalloy can be improved; and particularly, as a main raw material for additive manufacturing of high-performance metal components, the material has a very good application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of alloys, and in particular to a nickel-based high-temperature alloy powder and a preparation method and application thereof, and a nickel-based high-temperature alloy and a preparation method and application thereof. Background Art

[0002] Metal powder is a key raw material for additive manufacturing, and its quality largely determines the final quality of the product. The powder prepared by gas atomization powder making technology has the advantages of fine particle size, high sphericity, and low oxygen content, and has become the main raw material for additive manufacturing of high-performance metal components.

[0003] The basic principle of gas atomization is to impact the molten metal with a high-speed gas flow, convert the kinetic energy of the gas into the surface energy of the molten metal through collision, so that the molten metal flow is broken into fine droplets, and then quickly cooled and solidified in the gas flow atmosphere to form powder. At present, the mainstream atomization process is carried out in a vacuum or inert gas environment (the most commonly used inert gas is argon) to reduce the oxygen content and impurity content in the powder and improve the purity of the powder. However, the tensile properties of the alloy obtained after the nickel-based high-temperature alloy powder prepared by the above method are not good enough, which limits its application.

[0004] Chinese patent CN108941592A discloses a method for optimizing the sphericity and empty powder rate of nickel-based high-temperature alloy powder, wherein the nickel-based high-temperature alloy is melted to a molten state; a mixed gas of nitrogen and an inert gas is used as an atomizing gas to gas-atomize the molten nickel-based high-temperature alloy to obtain a nickel-based high-temperature alloy powder with optimized sphericity and empty powder rate; the volume ratio of nitrogen to inert gas (argon) in the mixed gas is 85:15 to 95:5; when gas-atomizing, the atomizing pressure of the mixed gas is 2.5 to 3.5 MPa. However, the tensile properties and plasticity of the nickel-based high-temperature alloy prepared by the nickel-based high-temperature alloy powder prepared by the above method are not high enough, the nitriding rate of the nitrogen atmosphere alone is slow, and a uniform nitride cannot be effectively formed, and the comprehensive mechanical properties are not good enough. Summary of the invention

[0005] In view of this, the object of the present invention is to provide a nickel-based high-temperature alloy powder and a preparation method and application thereof, a nickel-based high-temperature alloy and a preparation method and application thereof. The nickel-based high-temperature alloy powder provided by the present invention has high tensile strength, high elongation at break, excellent tensile properties and comprehensive plastic mechanical properties after molding, and the preparation cost of the nickel-based high-temperature alloy powder is low.

[0006] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0007] The present invention provides a method for preparing nickel-based high-temperature alloy powder, comprising the following steps:

[0008] The nickel-based high-temperature alloy raw material is heated until it is melted and then refined to obtain alloy liquid; the refining pressure is 1-6 MPa;

[0009] Atomizing and crushing the alloy liquid by high-pressure carrier gas to obtain nickel-based high-temperature alloy powder; the pressure of the high-pressure carrier gas is 4-6 MPa;

[0010] The melting, refining and atomization crushing are carried out under an inert atmosphere, which is nitrogen or argon.

[0011] Preferably, the nickel-based high-temperature alloy raw material includes simple substances, aluminum nitride and titanium nitride; the simple substances include Fe, Nb, Cr, Mo, Mn, Cu, Si and Ni;

[0012] Preferably, the melting includes vacuum melting, and the vacuum degree of the vacuum melting is 0.4-0.6 MPa;

[0013] The refining holding time is 12 to 20 minutes;

[0014] The temperatures of the melting and refining are independently 1480-1580°C.

[0015] Preferably, the alloy liquid is heated before the atomization and crushing;

[0016] The heating temperature is 1600-1750° C., the heat preservation time is 6 minutes, and the pressure is 1-6 MPa.

[0017] The present invention also provides a nickel-based high-temperature alloy powder obtained by the preparation method described in the above technical solution, wherein the nickel-based high-temperature alloy powder contains a nitride precipitation phase.

[0018] Preferably, the particle size of the nickel-based high-temperature alloy powder is 15 to 53 μm.

[0019] The present invention also provides a method for preparing a nickel-based high-temperature alloy, comprising the following steps: subjecting the nickel-based high-temperature alloy powder described in the above technical solution to laser powder bed melting process to obtain a nickel-based high-temperature alloy.

[0020] Preferably, the laser powder bed fusion process includes: drying nickel-based high temperature alloy powder, preheating the substrate, and performing 3D printing in an inert atmosphere;

[0021] The process parameters of the 3D printing include: laser power of 170-180W, scanning speed of 800-900mm / s, scanning layer thickness of 0.02-0.05mm, scanning spacing of 0.05-0.1mm, and oxygen content of the inert atmosphere of less than 1000ppm.

[0022] The present invention also provides a nickel-based high-temperature alloy prepared by the preparation method described in the above technical solution.

[0023] The present invention also provides the use of the nickel-based high-temperature alloy powder described in the above technical solution or the nickel-based high-temperature alloy described in the above technical solution as a raw material for additive manufacturing.

[0024] Compared with the traditional nickel-based high-temperature alloy smelting using single raw materials, the present invention adds aluminum nitride and titanium nitride in the selection of raw materials for nickel-based high-temperature alloy powder. During the preparation of the alloy powder, aluminum nitride and titanium nitride are dissolved and precipitated to form a strengthening phase, which can improve the tensile strength and elongation at break of the nickel-based high-temperature alloy. The nickel-based high-temperature alloy has excellent tensile properties and plastic comprehensive mechanical properties. It has a good application prospect as a raw material for additive manufacturing, especially as the main raw material for additive manufacturing of high-performance metal components.

[0025] In the process of preparing nickel-based high-temperature alloy powder according to the present invention, aluminum nitride and titanium nitride are dissolved and precipitated into a strengthening phase. The nickel-based high-temperature alloy obtained by forming the nickel-based high-temperature alloy powder through a laser powder bed melting process has the advantages of high strength, high elongation after fracture and high plasticity. It has a good application prospect as a raw material for additive manufacturing, especially as a main raw material for additive manufacturing of high-performance metal components. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The microstructure diagram of the nickel-based high-temperature alloy prepared in Example 1;

[0027] Figure 2 is the tensile property curve of the nickel-based high-temperature alloy prepared in Example 1;

[0028] Figure 3 The microstructure diagram of the nickel-based high-temperature alloy prepared in Example 2;

[0029] Figure 4 This is the tensile property curve of the nickel-based high-temperature alloy prepared in Example 2;

[0030] Figure 5 The microstructure diagram of the nickel-based high-temperature alloy prepared in Example 3;

[0031] Figure 6 This is the tensile property curve of the nickel-based high-temperature alloy prepared in Example 3;

[0032] Figure 7 It is a comparison curve of tensile properties of nickel-based high-temperature alloys prepared in Example 1 (within the process) and Comparative Example 1 (outside the process);

[0033] Figure 8 The tensile properties comparison curve of the nickel-based high-temperature alloy prepared in Example 1 (within the process) and Comparative Example 2 (outside the process);

[0034] Fig. 9 The tensile properties comparison curve of the nickel-based high-temperature alloy prepared in Example 1 (within the process) and Comparative Example 3 (outside the process); DETAILED DESCRIPTION

[0035] The present invention provides a method for preparing nickel-based high-temperature alloy powder, comprising the following steps:

[0036] The nickel-based high-temperature alloy raw material is heated until it is melted and then refined to obtain alloy liquid; the refining pressure is 1 to 6 MPa;

[0037] Atomizing and crushing the alloy liquid by high-pressure carrier gas to obtain nickel-based high-temperature alloy powder; the pressure of the high-pressure carrier gas is 4-6 MPa;

[0038] The melting, refining and atomization crushing are carried out under an inert atmosphere, which is nitrogen or argon.

[0039] Unless otherwise specified, the materials and equipment used in the present invention are all commercially available products in the art.

[0040] In the present invention, the nickel-based high-temperature alloy raw material preferably includes simple substances, aluminum nitride and titanium nitride; the simple substances preferably include Fe, Nb, Cr, Mo, Mn, Cu, Si and Ni.

[0041] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Fe15-19%, TiN 0.6-1.2%, Nb 4-7%, Cr 15-19%, Mo 2-5%, aluminum nitride 0.2-0.8%, Mn 0.05-0.1%, Cu 0.01-0.05%, Si 0.05-0.1%, and Ni balance.

[0042] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Fe15-19%, and in specific embodiments it may be 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, 18%, 18.5% or 19%.

[0043] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, 0.6-1.2% titanium nitride, and in specific embodiments it can be 0.6%, 0.65%, 0.7%, 0.75%, 0.8%, 0.85%, 0.9%, 0.95%, 1%, 1.05%, 1.1%, 1.15% or 1.2%.

[0044] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Nb4-7%, and in specific embodiments it may be 1%, 4.5%, 5%, 5.5%, 6%, 6.5% or 7%.

[0045] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Cr15-19%, and in specific embodiments it may be 15%, 15.5%, 16%, 16.5%, 17%, 17.5%, 18%, 18.5% or 19%.

[0046] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Mo2-5%, and in specific embodiments it may be 2%, 2.5%, 3%, 3.13%, 3.5%, 4%, 4.5% or 5%.

[0047] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, 0.2-0.8% aluminum nitride, and in specific embodiments it can be 0.2%, 0.25%, 0.3%, 0.35%, 0.4%, 0.45%, 0.5%, 0.55%, 0.6%, 0.65%, 0.7%, 0.75% or 0.8%.

[0048] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Mn 0.05-0.1%, and in specific embodiments it can be 0.05%, 0.055%, 0.06%, 0.065%, 0.07%, 0.075%, 0.08%, 0.085%, 0.09%, 0.095% or 0.1%.

[0049] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Cu 0.01-0.05%, and in specific embodiments it may be 0.01%, 0.015%, 0.02%, 0.025%, 0.03%, 0.035%, 0.04%, 0.045% or 0.05%.

[0050] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, by mass percentage, Si0.05-0.1%, and in specific embodiments it can be 0.01%, 0.015%, 0.02%, 0.025%, 0.03%, 0.035%, 0.04%, 0.045% or 0.05%.

[0051] In the present invention, the nickel-based high-temperature alloy raw material preferably includes, in terms of mass percentage: Ni balance.

[0052] In the present invention, the melting preferably includes vacuum melting; the vacuum degree of the vacuum melting is preferably 0.4-0.6 MPa, and in a specific embodiment of the present invention, it can be 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.55 MPa or 0.6 MPa; the melting temperature is preferably 1480-1580°C, more preferably 1500-1550°C, and in a specific embodiment of the present invention, it can be 1480°C, 1490°C, 1500°C, 1510°C, 1510°C, 1530°C, 1540°C, 1550°C, 1560°C, 1570°C or 1580°C, which is any temperature between 1480 and 1580°C, and no further enumeration is given here.

[0053] In the present invention, the refining pressure is preferably 1-6 MPa, and in a specific embodiment it can be 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa or 6 MPa; the refining holding time is preferably 12-20 min, and in a specific embodiment it can be 12 min, 13 min, 14 min, 15 min, 16 min, 17 min, 18 min, 19 min or 20 min; the refining temperature is preferably 1480-1580°C, more preferably 1500-1550°C, and in a specific embodiment it can be 1480°C, 1490°C, 1500°C, 1510°C, 1510°C, 1530°C, 1540°C, 1550°C, 1560°C, 1570°C or 1580°C, which is any temperature between 1480 and 1580°C, and no further enumeration is given here.

[0054] After the refining is completed, the present invention preferably further comprises evacuating to a vacuum degree of 0.4-0.6 MPa, which can be 0.4 MPa, 0.45 MPa, 0.5 MPa, 0.55 MPa or 0.6 MPa in a specific embodiment of the present invention.

[0055] In the present invention, the refining after heating to melting specifically preferably includes: placing the nickel-based high-temperature alloy raw material preferably in a crucible, placing it in a powder making furnace, closing the furnace cover, first evacuating the smelting chamber and the atomizing chamber, and then filling the furnace cavity with an inert atmosphere until the pressure in the furnace rises to the standard atmospheric pressure, and then evacuating the smelting chamber and the atomizing chamber for the second time, raising the furnace temperature to the smelting temperature, and refining the nickel-based high-temperature alloy raw material after it is melted; during the refining process, filling the furnace with an inert atmosphere until the pressure in the furnace is maintained at the refining pressure for refining; the vacuum degree after the first vacuuming and the second vacuuming is independently preferably 0.4-0.6MPa, and in a specific embodiment of the present invention, it can be 0.4MPa, 0.45MPa, 0.5MPa, 0.55MPa or 0.6MPa.

[0056] After obtaining the alloy liquid, the present invention uses high-pressure carrier gas to atomize and crush the alloy liquid to obtain nickel-based high-temperature alloy powder; the pressure of the high-pressure carrier gas is 4-6MPa.

[0057] In the present invention, the alloy liquid is preferably heated before the atomization and crushing, and then atomized and crushed by high-pressure carrier gas. In the present invention, the heating temperature is preferably 1600-1750°C, more preferably 1650-1700°C, and in a specific embodiment of the present invention, it can be 1600°C, 1610°C, 1620°C, 1630°C, 1640°C, 1650°C, 1660°C, 1670°C, 1680°C, 1690°C, 1700°C, 1710°C, 1720°C, 1730°C, 1740°C or 1750°C. ℃, which are not enumerated here; the heating insulation time is preferably 4 to 10 min, and in a specific embodiment it can be 4 min, 5 min, 6 min, 7 min, 8 min, 9 min or 10 min; the heating pressure is preferably 1 to 6 MPa, and in a specific embodiment it can be 1 MPa, 2 MPa, 3 MPa, 4 MPa, 5 MPa or 6 MPa; the present invention preferably introduces a nitrogen-containing atmosphere to a pressure of 1 to 6 MPa.

[0058] In the present invention, the pressure of the high-pressure carrier gas is 4-6 MPa, and in a specific embodiment, it can be 4 MPa, 4.5 MPa, 5 MPa or 6 MPa; the temperature of the high-pressure carrier gas is preferably ≤20°C.

[0059] In the present invention, the atomization and crushing operation specifically preferably includes: heating the alloy liquid in the smelting chamber to 1600-1750°C, and simultaneously filling the smelting chamber and the atomization chamber with an inert gas atmosphere to a pressure of 1-6MPa; turning on the exhaust fan of the atomization chamber, and then turning on the carrier gas passing into the atomization nozzle, and keeping the carrier gas temperature below 20°C; pouring the alloy solution into the tundish and then flowing into the nozzle, the alloy liquid is atomized and crushed by the high-pressure carrier gas to form spherical nickel-based high-temperature alloy powder, and the spherical nickel-based high-temperature alloy powder falls into a powder collecting tank at the lower end of the atomization chamber.

[0060] After the atomization and crushing, the present invention preferably further comprises: cooling the alloy powder obtained by the atomization and crushing to room temperature and then sieving and grading to obtain a nickel-based high-temperature alloy powder. In the present invention, the sieving and grading preferably includes airflow grading, and the sieving and grading is preferably performed in a sieving and grading machine. The present invention has no special restrictions on the conditions of the sieving and grading, and the nickel-based high-temperature alloy powder with a particle size of 15 to 53 μm can be used.

[0061] The present invention also provides a nickel-based high-temperature alloy powder prepared by the preparation method described in the above technical solution. In the present invention, the particle size of the nickel-based high-temperature alloy powder is preferably 15 to 53 μm, the fluidity is preferably ≤20s / 50g, and the bulk density is ≥4g / cm 3 .

[0062] The present invention also provides a method for preparing a nickel-based high-temperature alloy, comprising the following steps: subjecting the nickel-based high-temperature alloy powder described in the above technical solution to laser powder bed melting process to obtain a nickel-based high-temperature alloy.

[0063] In the present invention, the laser powder bed fusion process preferably includes: drying the nickel-based high-temperature alloy powder, preheating the substrate, and performing 3D printing in an inert atmosphere.

[0064] In the present invention, the drying temperature is preferably 70-100°C, more preferably 80-90°C, and in specific embodiments it can be 70°C, 75°C, 80°C, 85°C, 90°C, 95°C or 100°C; the drying time is preferably 1-3h, and in specific embodiments it can be 1h, 1.5h, 2h, 2.5h or 3h; the drying preferably includes vacuum drying.

[0065] The present invention preferably places the dried nickel-based high-temperature alloy powder in a powder storage bin of a 3D printer, starts preheating of a substrate, and then performs 3D printing according to the process parameters of 3D printing.

[0066] In the present invention, the preheating temperature is preferably 90-120°C, more preferably 100-110°C, and in specific embodiments may include 90°C, 95°C, 100°C, 105°C, 110°C, 115°C or 120°C.

[0067] In the present invention, the process parameters of the 3D printing preferably include: a laser power of 170 to 180 W, which may be 170 W, 171 W, 172 W, 173 W, 174 W, 175 W, 176 W, 177 W, 178 W, 179 W or 180 W in a specific embodiment of the present invention, which is any number between 170 and 180 W, and will not be enumerated here; a scanning speed of 800 to 900 mm / s, more preferably 850 to 880 mm / s, which may be 810 mm / s, 820 mm / s or more in a specific embodiment of the present invention. s, 830mm / s, 840mm / s, 850mm / s, 860mm / s, 870mm / s, 880mm / s, 890mm / s or 900mm / s, which is any number between 800 and 900mm / s, and no more exhaustive list is given here; the scanning layer thickness is 0.02 to 0.05mm, more preferably 0.03 to 0.04mm, the scanning interval is 0.05 to 0.1mm, more preferably 0.06 to 0.09mm, further preferably 0.07 to 0.08mm, and the oxygen content of the inert atmosphere is less than 1000ppm.

[0068] The present invention also provides a nickel-based high-temperature alloy prepared by the preparation method described in the above technical solution, wherein the nickel-based high-temperature alloy powder contains a nitride precipitation phase. In the present invention, the nitride precipitation phase is a solid solution precipitation phase of aluminum nitride and titanium nitride. In the present invention, the tensile strength of the nickel-based high-temperature alloy is preferably 890 to 1000 MPa, preferably 920 to 950 MPa, and in a specific embodiment of the present invention, it can be 890.1 MPa, 921.8 MPa, 925.45 MPa or 926.98 MPa; the elongation after fracture of the nickel-based high-temperature alloy is preferably 30 to 38%, more preferably 31 to 35%, and in a specific embodiment of the present invention, it can be 31.1478%, 31.87%, 34.5816% or 34.7397%.

[0069] The present invention also provides the use of the nickel-based high-temperature alloy powder described in the above technical solution or the nickel-based high-temperature alloy described in the above technical solution as an additive manufacturing raw material. In the present invention, the additive manufacturing raw material preferably includes additive manufacturing high-performance metal components. The nickel-based high-temperature alloy powder prepared by the present invention has the advantages of fine particle size, high sphericity, low oxygen content, etc. The nickel-based high-temperature alloy has the advantages of high strength, high elongation after fracture and high plasticity, etc., and has good application prospects as the main raw material for additive manufacturing of high-performance metal components.

[0070] In order to further illustrate the present invention, the nickel-based high-temperature alloy powder and its preparation method and application, the nickel-based high-temperature alloy and its preparation method and application provided by the present invention are described in detail below in combination with the embodiments, but they should not be understood as limiting the scope of protection of the present invention.

[0071] Example 1

[0072] Step 1, charging: iron, titanium nitride, niobium, chromium, molybdenum, aluminum nitride, manganese, copper, silicon, and nickel are loaded into a crucible of a powder making furnace; in terms of mass percentage, the loaded nickel-based high-temperature alloy raw materials are: Fe 17.5%, titanium nitride 0.9%, Nb 5.5%, Cr 17.5%, Mo 3.13%, aluminum nitride 0.5%, Mn 0.085%, Cu 0.02%, Si 0.075%, and Ni balance;

[0073] Step 2, smelting and refining: close the furnace cover, first evacuate the smelting chamber and the atomizing chamber to a vacuum degree of 0.6MPa, then fill the furnace cavity with high-purity nitrogen (mass concentration of 99.999%) until the pressure in the furnace rises to the standard atmospheric pressure, evacuate the smelting chamber and the atomizing chamber to a vacuum degree of 0.6MPa again, then increase the furnace temperature to 1500°C, gradually melt the charge, and keep it warm and refine for 15min to obtain a molten alloy; during the refining process, fill the furnace with high-purity nitrogen until the pressure in the furnace is maintained at 5MPa, and evacuate to a vacuum degree of 0.6MPa after the refining is completed;

[0074] Step 3, atomization: heat the alloy liquid in the furnace after refining in step 2 to 1650°C, keep it warm for 5 minutes, and at the same time fill the melting chamber and the atomizing chamber with high-purity nitrogen to a pressure of 3MPa; turn on the exhaust fan of the atomizing chamber, and then turn on the nitrogen passing into the atomizing nozzle, and keep the nitrogen temperature below 20°C; pour the alloy liquid into the tundish and then flow into the nozzle, the alloy liquid is atomized and crushed by the high-pressure nitrogen to form spherical nickel-based high-temperature alloy powder, and falls into the powder collecting tank at the lower end of the atomizing chamber;

[0075] Step 4, screening and grading: After the nickel-based high-temperature alloy powder in the powder collecting tank is cooled, the nickel-based high-temperature alloy powder in the powder collecting tank is collected in an air flow classifier, and the nickel-based high-temperature alloy powder with a particle size of 15 to 53 μm is obtained through air flow classification.

[0076] Step 5, laser powder bed fusion process: vacuum the nickel-based high-temperature alloy powder with a particle size of 15 to 53 μm with a powder drying machine, then bake the powder at 80°C for 2 hours, then take out the baked powder and put it into the powder storage bin of the 3D printer, start the substrate preheating, the preheating temperature is 100°C, and prepare high-strength nickel-based high-temperature alloy according to the 3D printing parameters. 3D printing parameters: laser power is 170W, scanning speed is 850mm / s, scanning layer thickness is 0.03mm, scanning spacing is 0.08mm, and oxygen content in argon atmosphere is <1000ppm.

[0077] The microstructure of nickel-based high-temperature alloys is Figure 1 As shown, it can be seen that the prepared nickel-based high-temperature alloy has a uniform distribution of precipitation phase and a good microstructure.

[0078] The tensile properties curve of nickel-based high-temperature alloy is as follows: Figure 2 As shown, it can be seen that the tensile strength is 1050.2897 MPa and the elongation after break is 40.7866%.

[0079] Example 2

[0080] Nickel-based high-temperature alloy powder and nickel-based high-temperature alloy were prepared according to the method of Example 1, the only difference from Example 1 being that high-purity nitrogen (mass concentration of 99.999%) was replaced with high-purity argon (mass concentration of 99.999%).

[0081] The microstructure of nickel-based high-temperature alloys is Figure 3 As shown, it can be seen that the prepared nickel-based high-temperature alloy has a uniform distribution of precipitation phase and a good microstructure.

[0082] The tensile properties curve of nickel-based high-temperature alloy is as follows: Figure 4 As shown, it can be seen that the tensile strength is 1002.2 MPa and the elongation after break is 35.52%.

[0083] Example 3

[0084] Nickel-based high-temperature alloy powder and nickel-based high-temperature alloy were prepared according to the method of Example 1, the only difference from Example 1 being that the nickel-based high-temperature alloy raw material contained 0.7% titanium nitride and 0.4% aluminum nitride.

[0085] The microstructure of nickel-based high-temperature alloys is Figure 5 As shown, it can be seen that the prepared nickel-based high-temperature alloy has a uniform distribution of precipitation phase and a good microstructure.

[0086] The tensile properties curve of nickel-based high-temperature alloy is as follows: Figure 6 As shown, it can be seen that the tensile strength is 983.51 MPa and the elongation after break is 34.03%.

[0087] Comparative Example 1

[0088] Nickel-based high-temperature alloy powder and nickel-based high-temperature alloy were prepared according to the method of Example 1, the only difference from Example 1 being that the nickel-based high-temperature alloy raw material contained 3% titanium nitride and 2% aluminum nitride.

[0089] The tensile properties comparison curves of the nickel-based high-temperature alloys prepared in Example 1 (within the process) and Comparative Example 1 (outside the process) are as follows: Figure 7 As shown, it can be seen that the tensile strength is 968.98 MPa, the elongation at break is 33.78%, and the tensile strength and elongation at break are significantly reduced compared with those in Example 1, that is, the tensile properties and plasticity of the nickel-based high-temperature alloy prepared in Comparative Example 1 are significantly reduced compared with those in Example 1.

[0090] Comparative Example 2

[0091] Nickel-based high-temperature alloy powder and nickel-based high-temperature alloy were prepared according to the method of Example 1. The only difference from Example 1 was that the aluminum nitride in the nickel-based high-temperature alloy raw material was replaced by aluminum alone, and the titanium nitride was replaced by titanium alone. The tensile strength of the prepared nickel-based high-temperature alloy was 944.99 MPa, and the elongation after fracture was 33.775%.

[0092] The tensile properties comparison curves of the nickel-based high-temperature alloys prepared in Example 1 and Comparative Example 2 are as follows: Figure 8 As shown, it can be seen that the mechanical properties of the nickel-based high-temperature alloy prepared by printing the nickel-based high-temperature alloy powder prepared by titanium nitride and aluminum nitride in the present invention are better than those of titanium and aluminum.

[0093] Comparative Example 3

[0094] Nickel-based high-temperature alloy powder and nickel-based high-temperature alloy were prepared according to the method of Example 1, and the only difference from Example 1 was: 3D printing parameters in step 5: laser power was 275 W, scanning speed was 960 mm / s, scanning layer thickness was 0.04 mm, scanning spacing was 0.1 mm, and oxygen content in argon atmosphere was <1000 ppm.

[0095] The tensile properties comparison curves of the nickel-based high-temperature alloys prepared in Example 1 (recorded as in-process) and Comparative Example 3 (recorded as out-of-process) are shown in FIG. Fig. 9 As shown, the tensile strength of the nickel-based high-temperature alloy prepared in Comparative Example 3 is 940.66 MPa, and the elongation after fracture is 31.215%. It can be seen that the strength and plasticity of the nickel-based high-temperature alloy prepared in Comparative Example 3 are greatly reduced compared with Example 1.

Claims

1. A method for preparing a nickel-based high-temperature alloy powder, characterized in that: The following steps are involved: The nickel-based high-temperature alloy raw material is heated until it is melted and then refined to obtain alloy liquid; the refining pressure is 1-6 MPa; Atomizing and crushing the alloy liquid by high-pressure carrier gas to obtain nickel-based high-temperature alloy powder; the pressure of the high-pressure carrier gas is 4-6 MPa; The melting, refining and atomization crushing are carried out under an inert atmosphere, which is nitrogen or argon.

2. The preparation method according to claim 1, characterized in that: The nickel-based high-temperature alloy raw materials include simple substances, aluminum nitride and titanium nitride; the simple substances include Fe, Nb, Cr, Mo, Mn, Cu, Si and Ni.

3. The preparation method according to claim 1 or 2, characterized in that: The melting includes vacuum melting, and the vacuum degree of the vacuum melting is 0.4-0.6MPa; The refining holding time is 12 to 20 minutes; The temperatures of the melting and refining are independently 1480-1580°C.

4. The preparation method according to claim 1, characterized in that: The alloy liquid is heated before the atomization and crushing; The heating temperature is 1600-1750° C., the heat preservation time is 6 minutes, and the pressure is 1-6 MPa.

5. The nickel-based high-temperature alloy powder obtained by the preparation method according to any one of claims 1 to 4, wherein the nickel-based high-temperature alloy powder contains a nitride precipitated phase.

6. The nickel-based high-temperature alloy powder according to claim 5, characterized in that: The particle size of the nickel-based high-temperature alloy powder is 15 to 53 μm.

7. A method for preparing a nickel-based high-temperature alloy, comprising the following steps: The nickel-based high-temperature alloy powder according to claim 5 or 6 is formed by laser powder bed melting process to obtain a nickel-based high-temperature alloy.

8. The preparation method according to claim 7, characterized in that: The laser powder bed fusion process includes: drying the nickel-based high-temperature alloy powder, preheating the substrate, and performing 3D printing in an inert atmosphere; The process parameters of the 3D printing include: laser power of 170-180W, scanning speed of 800-900mm / s, scanning layer thickness of 0.02-0.05mm, scanning spacing of 0.05-0.1mm, and oxygen content of the inert atmosphere of less than 1000ppm.

9. The nickel-based high-temperature alloy obtained by the preparation method according to claim 7 or 8.

10. Use of the nickel-based high-temperature alloy powder according to claim 5 or 6 or the nickel-based high-temperature alloy according to claim 9 as a raw material for additive manufacturing.

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