A method for manufacturing a titanium-aluminum alloy target

Abstract

This invention provides a method for preparing a titanium-aluminum alloy target material, comprising the following steps: (1) uniformly mixing titanium raw materials and aluminum raw materials to obtain a mixture; (2) smelting the mixture obtained in step (1) to obtain a molten alloy liquid; (3) using the molten alloy liquid obtained in step (2) for spray granulation, and then subjecting the spray-granulated particles to spark plasma sintering to obtain the titanium-aluminum alloy target material. The preparation method provided by this invention obtains alloy powder through spray granulation, and then prepares the titanium-aluminum alloy target material through spark plasma sintering. No plastic processing is required during the preparation process, and the obtained target material has low impurity content, fine and uniform grains, and excellent performance.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor technology and relates to a method for preparing a metal target, and more particularly to a method for preparing a titanium-aluminum alloy target. Background Technology

[0002] With the development of the electronics industry and sputtering technology, more and more materials need to be coated to achieve better results. Titanium-aluminum alloys, due to their high strength and wear resistance, have become the target material required for many materials. However, the existing titanium-aluminum alloy target preparation process has problems such as low target density, complex preparation process and high cost.

[0003] Moreover, titanium and aluminum have significantly different melting points, and the two elements can form a variety of metallic compounds, making it difficult to prepare titanium-aluminum alloys with uniform composition. The titanium-aluminum alloys prepared by existing technologies have uneven composition and are too expensive. Furthermore, the titanium-aluminum alloy targets contain a large number of defects such as shrinkage cavities and porosity.

[0004] CN112410739A discloses a method for preparing a titanium-aluminum alloy target, comprising mixing a main powder, a supplementary powder, and a trace powder evenly, filtering out large particulate impurities, and retaining uniformly sized powder particles to obtain a mixed powder; and immersing and cleaning the mixed powder in medical alcohol. This method improves the performance of the obtained titanium-aluminum alloy target by using a supplementary powder composed of silicon and magnesium powder and a trace powder composed of chromium powder, but the process is relatively complex and introduces elements such as silicon, magnesium, and chromium.

[0005] CN112725658A discloses a method for preparing a titanium-aluminum alloy target, comprising: dividing titanium raw materials into a first titanium raw material and a second titanium raw material; dividing aluminum raw materials into a first aluminum raw material and a second aluminum raw material; melting the first titanium raw material and the first aluminum raw material in a water-cooled copper crucible to obtain a first melt; cooling the first melt to obtain a first ingot; placing the first ingot at the bottom of the water-cooled copper crucible and adding the second titanium raw material and the second aluminum raw material to melt to obtain a second melt; cooling the second melt to obtain a second ingot; heating the second ingot to complete melting and refining it, then rapidly casting it to obtain a target blank; sequentially subjecting the target blank to cladding, degassing, hot isostatic pressing, and finally sintering it to obtain a sintered body; removing the cladding from the sintered body and machining it to obtain an aluminum-titanium alloy target.

[0006] CN114525479A discloses a method for preparing a titanium-aluminum alloy target, comprising the following steps: mixing titanium powder and aluminum powder in a vacuum rolling mixer to obtain a mixture; preparing a titanium-aluminum alloy target green blank by a rolling heating and melting process; hot-pressing and sintering the titanium-aluminum alloy target green blank to obtain a titanium-aluminum alloy target blank; and annealing the titanium-aluminum alloy target blank to obtain a titanium-aluminum alloy target.

[0007] Existing methods for preparing titanium-aluminum alloy targets include vacuum induction melting, vacuum arc remelting, and solidification melting. Regardless of the method, issues such as melting defects, component segregation, and impurities need to be addressed. Therefore, there is a need for a method to prepare titanium-aluminum alloy targets with small component deviations, high purity, and uniform, fine grains. Summary of the Invention

[0008] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a method for preparing titanium-aluminum alloy targets. The preparation method does not require plastic processing, and the resulting titanium-aluminum alloy targets have low impurity content, fine and uniform grains, and excellent performance.

[0009] To achieve this objective, the present invention adopts the following technical solution:

[0010] This invention provides a method for preparing a titanium-aluminum alloy target, the method comprising the following steps:

[0011] (1) The titanium raw material and the aluminum raw material are uniformly mixed to obtain a mixture;

[0012] (2) The mixture obtained in step (1) is smelted to obtain molten alloy liquid;

[0013] (3) The molten alloy liquid obtained in step (2) is sprayed and granulated, and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target.

[0014] The preparation method provided by the present invention obtains alloy powder by spray granulation, and then prepares titanium-aluminum alloy target material by spark plasma sintering. No plastic processing is required during the preparation process, and the obtained target material has low impurity content, fine and uniform grains, and excellent performance.

[0015] Preferably, the melting method in step (2) includes vacuum induction melting.

[0016] Preferably, the vacuum degree of the vacuum induction melting is 5×10⁻⁶. -2 Below Pa.

[0017] Preferably, after the vacuum induction melting is completed, the vacuum level is maintained for 3-4 hours, and then a protective gas is introduced to restore the normal pressure.

[0018] Preferably, the protective gas includes nitrogen and / or an inert gas.

[0019] Preferably, the gas used for spray granulation in step (3) includes nitrogen and / or an inert gas.

[0020] Preferably, the atomization pressure of the spray granulation in step (3) is 2-3 MPa.

[0021] Preferably, the axial sintering pressure of the discharge plasma sintering in step (3) is 50-70 MPa.

[0022] Preferably, the discharge plasma sintering in step (3) includes a first heating stage, a second heating stage and a third heating stage;

[0023] The final temperature of the first heating stage is 580-620℃;

[0024] The final temperature of the second heating stage is 1080-1120℃;

[0025] The final temperature of the third heating stage is 1200-1300℃.

[0026] Preferably, the heating rate in the first heating stage is 110-130℃ / min.

[0027] Preferably, the heating rate in the second heating stage is 90-110℃ / min.

[0028] Preferably, the heating rate of the third heating stage is 25-35℃ / min.

[0029] Preferably, the holding time for the discharge plasma sintering in step (3) is 30-60 min.

[0030] Preferably, the particle size D50 of the titanium raw material in step (1) is 10-20 mm.

[0031] Preferably, the particle size D50 of the aluminum raw material in step (1) is 10-20 mm.

[0032] Preferably, the titanium raw material and aluminum raw material in step (1) are ultrasonically cleaned and dried before mixing.

[0033] Preferably, the ultrasonic cleaning is performed in anhydrous ethanol.

[0034] Preferably, the drying temperature is 100-150℃ and the time is 2-3 hours.

[0035] Preferably, the titanium-aluminum atomic ratio in the mixture in step (1) is 1:(0.8-1.2).

[0036] As a preferred embodiment of the preparation method provided by the present invention, the preparation method includes the following steps:

[0037] (1) A titanium raw material with a particle size D50 of 10-20 mm and an aluminum raw material with a particle size D50 of 10-20 mm are uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:(0.8-1.2);

[0038] (2) Vacuum degree is 5×10-2 Under conditions below Pa, the mixture obtained in step (1) of vacuum induction melting; after the vacuum induction melting is completed, the vacuum degree is maintained for 3-4 hours, and then a protective gas is introduced to restore the normal pressure to obtain molten alloy liquid;

[0039] (3) Spray granulation is performed using the molten alloy liquid obtained in step (2), and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material; the axial sintering pressure of the discharge plasma sintering is 50-70 MPa; the discharge plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 110-130℃ / min, and the final temperature is 580-620℃; the heating rate of the second heating stage is 90-110℃ / min, and the final temperature is 1080-1120℃; the heating rate of the third heating stage is 25-35℃ / min, the final temperature is 1200-1300℃, and the holding time is 30-60 min.

[0040] The numerical range described in this invention includes not only the point values ​​listed above, but also any point values ​​within the numerical ranges not listed above. Due to space limitations and for the sake of brevity, this invention will not exhaustively list all the specific point values ​​included in the range.

[0041] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0042] The preparation method provided by the present invention obtains alloy powder by spray granulation, and then prepares titanium-aluminum alloy target material by spark plasma sintering. No plastic processing is required during the preparation process, and the obtained target material has low impurity content, fine and uniform grains, and excellent performance. Detailed Implementation

[0043] The technical solution of the present invention will be further illustrated below through specific embodiments.

[0044] An embodiment of the present invention provides a method for preparing a titanium-aluminum alloy target, the method comprising the following steps:

[0045] (1) The titanium raw material and the aluminum raw material are uniformly mixed to obtain a mixture;

[0046] (2) The mixture obtained in step (1) is smelted to obtain molten alloy liquid;

[0047] (3) The molten alloy liquid obtained in step (2) is sprayed and granulated, and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target.

[0048] The preparation method provided by the present invention obtains alloy powder by spray granulation, and then prepares titanium-aluminum alloy target material by spark plasma sintering. No plastic processing is required during the preparation process, and the obtained target material has low impurity content, fine and uniform grains, and excellent performance.

[0049] In the preparation method provided by this invention, considering the loss of raw materials during smelting, the amount of aluminum raw material added is increased by 1.5-2.5 wt% on the theoretical basis. For example, it can be 1.5 wt%, 1.8 wt%, 2 wt%, 2.2 wt%, or 2.5 wt%, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0050] The titanium-aluminum alloy target material described in this invention is a target blank commonly made in the art. The final target material product is obtained by performing conventional machining on the target blank.

[0051] In some embodiments, the melting method in step (2) includes vacuum induction melting.

[0052] In some embodiments, the vacuum degree of the vacuum induction melting is 5 × 10⁻⁶. -2 Below Pa, for example, it could be 1×10 -2 Pa, 2×10 -2 Pa, 3×10 -2 Pa, 4×10 -2 Pa or 5×10 -2 Pa, but not limited to the listed values, applies to other unlisted values ​​within the range as well.

[0053] In some embodiments, after the vacuum induction melting is completed, the vacuum level is maintained for 3-4 hours, and then a protective gas is introduced to restore the atmospheric pressure.

[0054] In this invention, after vacuum induction melting is completed, the vacuum level is maintained for 3-4 hours, for example, 3 hours, 3.2 hours, 3.5 hours, 3.8 hours or 4 hours, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0055] In some embodiments, the protective gas includes nitrogen and / or an inert gas.

[0056] In some embodiments, the gas used for spray granulation in step (3) includes nitrogen and / or an inert gas. The inert gas includes any one or a combination of at least two of helium, neon, or argon, with typical but non-limiting combinations including a combination of helium and neon, a combination of helium and argon, a combination of helium and argon, or a combination of helium, neon, and argon.

[0057] In some embodiments, the atomization pressure of the spray granulation in step (3) is 2-3 MPa, for example, it can be 2 MPa, 2.2 MPa, 2.5 MPa, 2.8 MPa or 3 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0058] For example, the nozzle diameter used in the spray granulation of the present invention is 2.5-3.5 mm, such as 2.5 mm, 3 mm or 3.5 mm, but not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0059] In some embodiments, the axial sintering pressure of the discharge plasma sintering in step (3) is 50-70 MPa, for example, it can be 50 MPa, 55 MPa, 60 MPa, 65 MPa or 70 MPa, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0060] In some embodiments, the discharge plasma sintering in step (3) includes a first heating stage, a second heating stage and a third heating stage.

[0061] The final temperature of the first heating stage is 580-620℃, for example, it can be 580℃, 590℃, 600℃, 610℃ or 620℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0062] The final temperature of the second heating stage is 1080-1120℃, for example, it can be 1080℃, 1090℃, 1100℃, 1110℃ or 1120℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0063] The final temperature of the third heating stage is 1200-1300℃, for example, it can be 1200℃, 1220℃, 1250℃, 1280℃ or 1300℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0064] In some embodiments, the heating rate of the first heating stage is 110-130℃ / min, for example, it can be 110℃ / min, 115℃ / min, 120℃ / min, 125℃ / min or 130℃ / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0065] In some embodiments, the heating rate of the second heating stage is 90-110°C / min, for example, it can be 90°C / min, 95°C / min, 100°C / min, 105°C / min or 110°C / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0066] In some embodiments, the heating rate of the third heating stage is 25-35°C / min, for example, it can be 25°C / min, 28°C / min, 30°C / min, 32°C / min or 35°C / min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0067] In some embodiments, the holding time for the discharge plasma sintering in step (3) is 30-60 min, for example, it can be 30 min, 35 min, 40 min, 45 min, 50 min, 55 min or 60 min, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0068] In some embodiments, the particle size D50 of the titanium raw material in step (1) is 10-20 mm, for example, it can be 10 mm, 12 mm, 15 mm, 18 mm or 20 mm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0069] In some embodiments, the particle size D50 of the aluminum raw material in step (1) is 10-20 mm, for example, it can be 10 mm, 12 mm, 15 mm, 18 mm or 20 mm, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0070] In some embodiments, the titanium and aluminum raw materials in step (1) are ultrasonically cleaned and dried before mixing.

[0071] In some embodiments, the ultrasonic cleaning is performed in anhydrous ethanol.

[0072] In some embodiments, the drying temperature is 100-150°C and the time is 2-3 hours.

[0073] The drying temperature described in this invention is 100-150℃, for example, it can be 100℃, 110℃, 120℃, 130℃, 140℃ or 150℃, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0074] In some embodiments, the titanium-aluminum atomic ratio in the mixture in step (1) is 1:(0.8-1.2), for example, it can be 1:0.8, 1:0.9, 1:1, 1:1.1 or 1:1.2, but is not limited to the listed values. Other unlisted values ​​within the range are also applicable.

[0075] In some embodiments, the preparation method includes the following steps:

[0076] (1) A titanium raw material with a particle size D50 of 10-20 mm and an aluminum raw material with a particle size D50 of 10-20 mm are uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:(0.8-1.2);

[0077] (2) Vacuum degree is 5×10 -2 Under conditions below Pa, the mixture obtained in step (1) of vacuum induction melting; after the vacuum induction melting is completed, the vacuum degree is maintained for 3-4 hours, and then a protective gas is introduced to restore the normal pressure to obtain molten alloy liquid;

[0078] (3) Spray granulation is performed using the molten alloy liquid obtained in step (2), and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material; the axial sintering pressure of the discharge plasma sintering is 50-70 MPa; the discharge plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 110-130℃ / min, and the final temperature is 580-620℃; the heating rate of the second heating stage is 90-110℃ / min, and the final temperature is 1080-1120℃; the heating rate of the third heating stage is 25-35℃ / min, the final temperature is 1200-1300℃, and the holding time is 30-60 min.

[0079] To clearly illustrate the technical solution of the present invention, in the specific embodiment of the present invention, the purity of the titanium raw material is 99.98 wt% and the purity of the aluminum raw material is 99.99 wt%. The purity of the above-mentioned titanium and aluminum raw materials is not considered as a limitation on the raw materials, but is only for better illustrating the technical solution.

[0080] Example 1

[0081] This embodiment provides a method for preparing a titanium-aluminum alloy target, the method comprising the following steps:

[0082] (1) Titanium raw material with a particle size D50 of 15 mm and aluminum raw material with a particle size D50 of 15 mm are uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:1; the titanium raw material and aluminum raw material are ultrasonically cleaned and dried before mixing; the ultrasonic cleaning is carried out in anhydrous ethanol; the drying temperature is 125℃ and the time is 2.5h.

[0083] (2) The vacuum degree is 3×10 -2 Under the condition of Pa, the mixture obtained in the vacuum induction melting step (1); after the vacuum induction melting is completed, the vacuum degree is maintained for 3.5h, and then helium is introduced to restore the normal pressure to obtain molten alloy liquid;

[0084] (3) The molten alloy liquid obtained in step (2) is sprayed and granulated, and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material.

[0085] The gas used for spray granulation is helium, the atomization pressure is 2.5 MPa, and the nozzle diameter for spray granulation is 3 mm.

[0086] The axial sintering pressure of the spark plasma sintering is 60 MPa; the spark plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 120 °C / min, and the final temperature is 600 °C; the heating rate of the second heating stage is 100 °C / min, and the final temperature is 1100 °C; the heating rate of the third heating stage is 30 °C / min, the final temperature is 1250 °C, and the holding time is 45 min.

[0087] Example 2

[0088] This embodiment provides a method for preparing a titanium-aluminum alloy target, the method comprising the following steps:

[0089] (1) Titanium raw material with a particle size D50 of 10 mm and aluminum raw material with a particle size D50 of 10 mm are uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:1; the titanium raw material and aluminum raw material are ultrasonically cleaned and dried before mixing; the ultrasonic cleaning is carried out in anhydrous ethanol; the drying temperature is 100℃ and the time is 3h.

[0090] (2) The vacuum degree is 1×10 -2 Under the condition of Pa, the mixture obtained in the vacuum induction melting step (1); after the vacuum induction melting is completed, the vacuum degree is maintained for 3 hours, and then helium is introduced to restore the normal pressure to obtain molten alloy liquid;

[0091] (3) The molten alloy liquid obtained in step (2) is sprayed and granulated, and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material.

[0092] The gas used for spray granulation is helium, the atomization pressure is 2MPa, and the nozzle diameter for spray granulation is 3mm.

[0093] The axial sintering pressure of the spark plasma sintering is 50 MPa; the spark plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 110 °C / min, and the final temperature is 580 °C; the heating rate of the second heating stage is 90 °C / min, and the final temperature is 1080 °C; the heating rate of the third heating stage is 25 °C / min, the final temperature is 1200 °C, and the holding time is 60 min.

[0094] Example 3

[0095] This embodiment provides a method for preparing a titanium-aluminum alloy target, the method comprising the following steps:

[0096] (1) Titanium raw material with a particle size D50 of 20 mm and aluminum raw material with a particle size D50 of 20 mm are uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:1; the titanium raw material and aluminum raw material are ultrasonically cleaned and dried before mixing; the ultrasonic cleaning is carried out in anhydrous ethanol; the drying temperature is 150℃ and the time is 2h.

[0097] (2) The vacuum degree is 5×10 -2 Under the condition of Pa, the mixture obtained in the vacuum induction melting step (1); after the vacuum induction melting is completed, the vacuum degree is maintained for 4 hours, and then helium is introduced to restore the normal pressure to obtain molten alloy liquid;

[0098] (3) The molten alloy liquid obtained in step (2) is sprayed and granulated, and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material.

[0099] The gas used for spray granulation is helium, the atomization pressure is 3MPa, and the nozzle diameter for spray granulation is 3mm.

[0100] The axial sintering pressure of the spark plasma sintering is 70 MPa; the spark plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 130℃ / min, and the final temperature is 620℃; the heating rate of the second heating stage is 110℃ / min, and the final temperature is 1120℃; the heating rate of the third heating stage is 35℃ / min, the final temperature is 1300℃, and the holding time is 30 min.

[0101] Example 4

[0102] This embodiment provides a method for preparing a titanium-aluminum alloy target. Except for the titanium-aluminum atomic ratio of 1:0.8 in the mixture described in step (1), the rest is the same as in Example 1.

[0103] Example 5

[0104] This embodiment provides a method for preparing a titanium-aluminum alloy target. Except for the titanium-aluminum atomic ratio of 1:1.2 in the mixture described in step (1), the rest is the same as in Example 1.

[0105] Example 6

[0106] This embodiment provides a method for preparing a titanium-aluminum alloy target. In this embodiment, except that the heating rate in the first heating stage is 100℃ / min, the rest is the same as in Example 1.

[0107] Example 7

[0108] This embodiment provides a method for preparing a titanium-aluminum alloy target. In this embodiment, except that the heating rate in the first heating stage is 120℃ / min, the rest is the same as in Example 1.

[0109] Example 8

[0110] This embodiment provides a method for preparing a titanium-aluminum alloy target. Except for the heating rate of 20℃ / min in the third heating stage, the rest is the same as in Example 1.

[0111] Example 9

[0112] This embodiment provides a method for preparing a titanium-aluminum alloy target. Except for the heating rate of 40℃ / min in the third heating stage, the rest is the same as in Example 1.

[0113] Comparative Example 1

[0114] This comparative example provides a method for preparing a titanium-aluminum alloy target, the method comprising the following steps:

[0115] (1) Titanium raw material with a particle size D50 of 15 mm and aluminum raw material with a particle size D50 of 15 mm are uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:1; the titanium raw material and aluminum raw material are ultrasonically cleaned and dried before mixing; the ultrasonic cleaning is carried out in anhydrous ethanol; the drying temperature is 125℃ and the time is 2.5h.

[0116] (2) The obtained mixture is subjected to spark plasma sintering to obtain the titanium-aluminum alloy target material;

[0117] The gas used for spray granulation is helium, the atomization pressure is 2.5 MPa, and the nozzle diameter for spray granulation is 3 mm.

[0118] The axial sintering pressure of the spark plasma sintering is 60 MPa; the spark plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 120 °C / min, and the final temperature is 600 °C; the heating rate of the second heating stage is 100 °C / min, and the final temperature is 1100 °C; the heating rate of the third heating stage is 30 °C / min, the final temperature is 1250 °C, and the holding time is 45 min.

[0119] The preparation method provided in this comparative example cannot form alloy grains, and it is impossible to detect the average grain size of the final product.

[0120] The purity and average grain size of the titanium-aluminum alloy targets obtained in Examples 1-9 and Comparative Example 1 were tested. The purity was detected by glow discharge mass spectrometry (GDMS), and the average grain size was detected by GB / T 6394-2017 "Method for Determination of Average Grain Size of Metals".

[0121] The results are shown in Table 1.

[0122] Table 1

[0123] Purity (wt%) Average grain size (μm) Example 1 99.998 56 Example 2 99.994 65 Example 3 99.996 62 Example 4 99.995 58 Example 5 99.996 60 Example 6 99.997 73 Example 7 99.997 77 Example 8 99.997 63 Example 9 99.997 66 Comparative Example 1 99.991 -

[0124] In summary, the preparation method provided by this invention obtains alloy powder through spray granulation, and then prepares titanium-aluminum alloy target material through spark plasma sintering. No plastic processing is required during the preparation process, and the obtained target material has low impurity content, fine and uniform grains, and excellent performance.

[0125] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a titanium-aluminum alloy target material with small component deviation, high purity, and uniform and fine grains, characterized in that, The preparation method includes the following steps: (1) The titanium raw material and the aluminum raw material are uniformly mixed to obtain a mixture; (2) The mixture obtained in step (1) is smelted to obtain molten alloy liquid; (3) The molten alloy liquid obtained in step (2) is sprayed and granulated, and then the granulated particles are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material. Step (3) of the discharge plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 110-130℃ / min; the heating rate of the third heating stage is 25-35℃ / min; the end temperature of the first heating stage is 580-620℃; the end temperature of the second heating stage is 1080-1120℃; and the end temperature of the third heating stage is 1200-1300℃.

2. The preparation method according to claim 1, characterized in that, The melting method described in step (2) includes vacuum induction melting.

3. The preparation method according to claim 2, characterized in that, The vacuum degree of the vacuum induction melting is 5×10. - 2 Below Pa.

4. The preparation method according to claim 2, characterized in that, After the vacuum induction melting is completed, maintain the vacuum level for 3-4 hours, and then introduce protective gas to restore normal pressure.

5. The preparation method according to claim 4, characterized in that, The protective gas includes nitrogen and / or an inert gas.

6. The preparation method according to claim 1, characterized in that, The gas used in the spray granulation in step (3) includes nitrogen and / or inert gas.

7. The preparation method according to claim 1, characterized in that, The atomization pressure of the spray granulation in step (3) is 2-3 MPa.

8. The preparation method according to claim 1, characterized in that, The axial sintering pressure of the spark plasma sintering in step (3) is 50-70 MPa.

9. The preparation method according to claim 1, characterized in that, The heating rate in the second heating stage is 90-110℃ / min.

10. The preparation method according to claim 1, characterized in that, The holding time for the discharge plasma sintering in step (3) is 30-60 min.

11. The preparation method according to claim 1, characterized in that, The particle size D50 of the titanium raw material in step (1) is 10-20 mm.

12. The preparation method according to claim 1, characterized in that, The particle size D50 of the aluminum raw material in step (1) is 10-20 mm.

13. The preparation method according to claim 1, characterized in that, In step (1), the titanium and aluminum raw materials are ultrasonically cleaned and dried before mixing.

14. The preparation method according to claim 13, characterized in that, The ultrasonic cleaning was performed in anhydrous ethanol.

15. The preparation method according to claim 13, characterized in that, The drying temperature is 100-150℃, and the time is 2-3 hours.

16. The preparation method according to claim 1, characterized in that, The titanium-aluminum atomic ratio in the mixture in step (1) is 1:(0.8-1.2).

17. The preparation method according to claim 1, characterized in that, The preparation method includes the following steps: (1) A mixture of titanium raw material with a particle size D50 of 10-20 mm and aluminum raw material with a particle size D50 of 10-20 mm was uniformly mixed to obtain a mixture with a titanium-aluminum atomic ratio of 1:(0.8-1.2); (2) Vacuum degree is 5×10 -2 Under conditions below Pa, the mixture obtained in step (1) of vacuum induction melting; after the vacuum induction melting is completed, the vacuum degree is maintained for 3-4 hours, and then a protective gas is introduced to restore the normal pressure to obtain molten alloy liquid; (3) Spray granulation is performed using the molten alloy liquid obtained in step (2), and then the particles obtained by spray granulation are subjected to discharge plasma sintering to obtain the titanium-aluminum alloy target material; the axial sintering pressure of the discharge plasma sintering is 50-70 MPa; the discharge plasma sintering includes a first heating stage, a second heating stage and a third heating stage; the heating rate of the first heating stage is 110-130℃ / min, and the final temperature is 580-620℃; the heating rate of the second heating stage is 90-110℃ / min, and the final temperature is 1080-1120℃; the heating rate of the third heating stage is 25-35℃ / min, the final temperature is 1200-1300℃, and the holding time is 30-60 min.