Device for preparing spherical titanium carbide powder and method thereof

Abstract

The application relates to a method for preparing spherical titanium carbide powder, which is prepared by using a laser spheroidization device, and steps are as follows: TiO2 powder and carbon black are mixed by ball milling at a molar ratio of 1:1; spray granulation is carried out to obtain mixed granulation powder; a reaction chamber is vacuumized to below 0.1 Pa, argon is introduced from a protective gas inlet of the laser spheroidization device, a laser generator and an auxiliary device are started, a stable laser beam flow with a focused light spot area is formed; a powder feeder is started, powder feeding gas flow and powder feeding rate are controlled, the mixed granulation powder is fed into the laser beam flow, spheroidization and reaction are carried out in the focused light spot area, and the spherical titanium carbide powder is prepared. The application has the advantages of short technological process, extremely short reaction time, greatly improved production efficiency, and foundation for realizing industrialized production of the spherical titanium carbide powder; and the prepared TiC powder has high purity.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of additive manufacturing technology, and more particularly, to a method for preparing spherical titanium carbide powder by laser spheroidization, and more particularly, to a device and method for preparing spherical titanium carbide powder. BACKGROUND

[0002] Titanium carbide (TiC) is a typical transition metal carbide. Its bond type is a mixture of ionic, covalent and metallic bonds in the same crystal structure, so titanium carbide has many unique properties. The structure of the crystal determines that titanium carbide has high hardness, high melting point, wear resistance and electrical conductivity, etc. Titanium carbide is an important reinforcing agent in metal matrix composites, and its products are widely used in many fields such as machinery, electronics, chemical industry, environmental protection, fusion reactor, national defense industry, etc. Especially, titanium carbide ultrafine composite powder as a reinforcing phase of composite material has great development value and application prospect. Therefore, the preparation of high-purity, small particle size, and narrow particle size distribution titanium carbide powder material is the current research hotspot. Compared with non-spherical titanium carbide powder, the mechanical properties of spherical titanium carbide are the same in all directions, and it is easier to obtain products with excellent performance in plasma thermal spraying and laser cladding, and it is often used as an additive to nickel-based, iron-based and titanium-based powders as a reinforcing phase. Therefore, there is an urgent need for a spherical titanium carbide preparation method with simple preparation process, high spheroidization rate and high purity.

[0003] In the patent with Chinese patent publication number CN111422874A, titanium powder and carbon black are mixed by ball milling at a molar ratio of 1:1, spray granulation is carried out to obtain granulated powder, and spherical titanium carbide powder is obtained by plasma spheroidization. The patent with Chinese patent publication number CN107364865A discloses a preparation method in which irregularly shaped titanium carbide powder prepared by carbothermal reduction of TiO2 is carried by a carrier gas to a plasma torch for spheroidization to obtain titanium carbide powder. However, the domestic plasma atomization equipment currently relies on import from Canada Tekna Company, and is of trial level. Industrial-grade plasma equipment is complex and has high production cost, which limits the use of titanium carbide powder and poses the risk of neck blockage.

[0004] The patent with Chinese patent publication number CN115818646A discloses a method in which titanium dioxide powder and calcium carbide are mixed uniformly at a certain ratio, then pressed into tablets, and calcined under argon protection to form titanium carbide and calcium oxide. The product is crushed and washed to remove calcium oxide and other impurities to obtain titanium carbide powder. However, the main disadvantage of this method is that the process is long, and there is pollution in the processes of extrusion, sintering, crushing and washing, resulting in high impurity content of the final titanium carbide powder.

[0005] Therefore, it is desirable to provide a device for preparing spherical titanium carbide powder and a method thereof to solve the problems of low purity, low spheroidization rate and high production cost of TiC powder. SUMMARY

[0006] The present application aims to solve the problems of complex preparation process, low spheroidization rate and low purity of TiC powder, and therefore provides a device for preparing spherical titanium carbide powder and a method thereof.

[0007] To solve the above technical problems, the present application adopts the following technical solutions:

[0008] According to one aspect of the present application, a method for preparing spherical titanium carbide powder is provided, which is prepared by using a laser spheroidization device, and specifically includes the following steps:

[0009] 1) TiO2 powder and carbon black are mixed by ball milling at a molar ratio of 1:1;

[0010] 2) Spray granulation to obtain mixed granulated powder of TiO2 powder and carbon black;

[0011] 3) Beam current: the reaction chamber is vacuumed to below 0.1 pa, argon gas is introduced from the protective gas inlet of the laser spheroidization device, and the laser generator and auxiliary equipment are turned on to form a stable laser beam current with a focused spot area;

[0012] 4) Powder feeding: the powder feeder is turned on to control the powder feeding gas flow and powder feeding rate, the mixed granulated powder is fed into the laser beam current, and spheroidization and reaction are carried out in the focused spot area of the laser beam current to prepare spherical titanium carbide powder.

[0013] In one embodiment of the present application, in step 1), the particle size of TiO2 powder is 10-25 μm, and the particle size of carbon black is 20-53 μm.

[0014] In one embodiment of the present application, in step 1), argon gas protection is provided during ball milling, the ball milling speed is 180 rad / min, the time is 20 h, and the ball-to-material ratio is 26:1.

[0015] In one embodiment of the present application, in step 2), the nozzle speed during spray granulation is 11800 rad / min, and the particle size of the mixed granulated powder is 74-145 μm.

[0016] In one embodiment of the present application, in step 3), the purity of argon gas is ≥99.999%, and the flow rate of argon gas introduced is 2.5 L / min.

[0017] In one embodiment of the present application, in step 3), the power of the laser generator is 2.0-6.0 kW, and the spot diameter in the focused spot area is 3.5-6.5 mm.

[0018] In one embodiment of the present application, in step 4), the powder feeding gas is argon with a purity of ≥99.999%, and the powder feeding gas flow is 3.8 L / min, and the powder feeding rate is 13-17 g / min.

[0019] In one embodiment of the present application, in step 4), the particle size of the prepared titanium carbide powder is 53-105 μm.

[0020] In one embodiment of the present application, the laser beam stream adopts a high energy density beam stream.

[0021] According to another aspect of the present application, a device for preparing spherical titanium carbide powder is provided, which comprises a laser spheroidization device prepared by the method for preparing spherical titanium carbide powder as described above.

[0022] By adopting the technical solution described above, the present application has the following advantages compared with the prior art:

[0023] The present application uses TiO2 powder or carbon black as raw material, and argon as reaction gas to prepare titanium carbide powder, and has a short process flow and extremely short reaction time, greatly improving the production efficiency and laying a foundation for realizing the industrialized production of spherical titanium carbide powder.

[0024] The powder prepared by the present application has controllable particle size and sphericity, and the particle size and sphericity of the powder can be controlled by controlling the laser power, spot diameter and powder feeding rate.

[0025] The present application uses laser as heat source, has high energy density, and the mixed powder has no contact with the outside world during the high-temperature reaction process, and no external impurities are introduced, so that the prepared TiC powder has high purity. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A flowchart of a method for preparing spherical titanium carbide powder provided by the present application is shown;

[0027] Figure 2 An SEM image of the spherical titanium carbide powder prepared in Example 1 of the present application is shown;

[0028] Figure 3 An SEM image of the spherical titanium carbide powder prepared in Example 2 of the present application is shown;

[0029] Figure 4 An SEM image of the spherical titanium carbide powder prepared in Example 3 of the present application is shown. DETAILED DESCRIPTION

[0030] It should be understood that the embodiments of the application shown in the example embodiments are only illustrative. Although only a few embodiments are described in detail in the present application, those skilled in the art can easily appreciate that various modifications are possible without departing from the teachings of the subject matter of the present application. Accordingly, all such modifications should be included within the scope of the present application. Other substitutions, modifications, changes and omissions can be made to the design, operating conditions and parameters of the following example embodiments without departing from the spirit of the present application.

[0031] As shown in Figure 1 The present application provides a method for preparing spherical titanium carbide powder, which is prepared by using a laser spheroidization device, and specifically comprises the following steps:

[0032] Step S101: TiO2 powder and carbon black are mixed by ball milling at a molar ratio of 1:1;

[0033] Step S102: Spray granulation to obtain mixed granulated powder of TiO2 powder and carbon black;

[0034] Step S103: The reaction chamber is vacuumed to below 0.1 pa, argon gas is introduced from the protective gas inlet of the laser spheroidization device, and the laser generator and the auxiliary equipment are turned on to form a stable laser beam stream with a focused spot area;

[0035] Step S104: Powder feeding: the powder feeder is turned on, the powder feeding gas flow and the powder feeding rate are controlled, the mixed granulated powder is fed into the laser beam stream, and spheroidization and reaction are carried out in the focused spot area of the laser beam stream to prepare spherical titanium carbide powder.

[0036] The present application uses TiO2 powder or carbon black as raw material and argon gas as reaction gas to prepare titanium carbide powder, which has a short process flow and extremely short reaction time, greatly improves the production efficiency, and lays a foundation for realizing the industrialized production of spherical titanium carbide powder; the particle size and sphericity of the powder prepared by the present application are controllable; the particle size and sphericity of the powder are controlled by controlling the laser power, spot diameter and powder feeding rate; the present application uses laser as heat source, has high energy density, and the mixed powder has no contact with the outside during high-temperature reaction, without introducing external impurities, so that the prepared TiC powder has high purity.

[0037] In the above method, in step S101, the particle size of the TiO2 powder is 10-25 μm, and the particle size of the carbon black is 20-53 μm.

[0038] In the above method, in step S101, preferably, argon gas protection is provided during the ball milling process, the ball milling speed is 180 rad / min, the time is 20 h, and the ball-to-material ratio is 26:1.

[0039] In the above method, in step S102, preferably, the nozzle rotation speed in the spray granulation process is 11800 rad / min, and the particle size of the mixed granulation powder is 74-145 μm.

[0040] In the above method, in step S103, the purity of the argon is ≥99.999%, the flow rate of the argon is 2.5 L / min; the power of the laser generator is 2.0-6.0 kW, and the spot diameter in the focused light spot area is 3.5-6.5 mm.

[0041] In the above method, in step S104, the powder feeding gas is argon, the purity is ≥99.999%, the powder feeding gas flow rate is 3.8 L / min, and the powder feeding rate is 13-17 g / min.

[0042] In the above method, in step S104, the particle size of the prepared titanium carbide powder is 53-105 μm.

[0043] In the above method, the laser beam flow is a high-energy density beam flow.

[0044] In addition, the application also provides a device for preparing spherical titanium carbide powder, which comprises a laser spheroidizing device prepared by the method for preparing spherical titanium carbide powder as described above.

[0045] The above technical solutions of the application will be described in detail through specific embodiments.

[0046] The technical solution adopted by the application is that TiO2 powder and carbon black are mixed in a proportion of 1:1 in terms of molar ratio, spray granulation is performed to obtain mixed granulation powder, the mixed powder is heated and reacted in the focused light spot area of the laser beam and is melted into a spherical shape to generate spherical titanium carbide powder.

[0047] Specifically, a method for preparing spherical titanium carbide powder comprises the following steps of mixing, granulation and laser spheroidizing.

[0048] (1) TiO2 powder and carbon black are mixed in a proportion of 1:1 in terms of molar ratio to be fully mixed;

[0049] (2) Spray granulation is performed to obtain mixed granulation powder of titanium powder and carbon black;

[0050] (3) Beam flow is started: vacuum is extracted to below 0.1 pa, argon is introduced from the protective gas inlet of the laser spheroidizing device, and the laser generator and the auxiliary equipment are started to form a stable laser beam flow with a focused light spot area;

[0051] (4) Powder feeding: open the powder feeder, control the powder feeding gas flow and powder feeding rate, and mix the granulated powder into the focused light spot area, spheroidize and react under the high energy density beam to obtain spherical titanium carbide powder.

[0052] In the above method, preferably, in order to ensure that the particle size of the titanium carbide powder is 53-105 μm, the particle size of the TiO2 powder in step (1) is 10-25 μm, and the particle size of the carbon black is 20-53 μm.

[0053] In the above method, preferably, in the ball milling process in step (1), argon is protected, the ball milling speed is 180 rad / min, the time is 20 h, and the ball-to-material ratio is 26:1.

[0054] In the above method, preferably, in step (2), the nozzle speed in the spray granulation process is 11800 rad / min, and the particle size of the mixed granulated powder is 74-145 μm.

[0055] In the above method, preferably, in step (3), the flow rate of argon is 2.5 L / min, the purity is ≥99.999%, the power of the laser generator is 2.0-6.0 kW, and the spot diameter is 3.5-6.5 mm.

[0056] In the above method, preferably, the powder feeding rate is 13-17 g / min, the powder feeding gas flow is 3.8 L / min, the powder feeding gas is argon, and the purity is ≥99.999%.

[0057] Example 1

[0058] A method for preparing spherical titanium carbide powder, comprising the following steps:

[0059] (1) mixing TiO2 powder with a particle size of 10-25 μm and carbon black with a particle size of 20-53 μm at a molar ratio of 1:1, using a planetary ball mill for ball milling at a speed of 11800 rad / min for 20 h, and a ball-to-material ratio of 26:1;

[0060] (2) spray granulation using a spray granulator to obtain mixed granulated powder of TiO2 and carbon black with a particle size of 74-145 μm;

[0061] (3) vacuuming the reaction chamber to 0.1 pa, introducing argon from the protective gas inlet of the laser spheroidization equipment, turning on the laser generator and auxiliary equipment, and forming a stable laser beam with a focused light spot area, wherein the operating parameters of the laser spheroidization equipment are set as follows: the flow rate of argon is 2.5 L / min, the laser power is 2.5 kW, and the spot diameter is 3.5 mm;

[0062] (4) Turn on the powder feeder, control the powder gas flow to be 3.8 L / min and the powder feeding rate to be 13 g / min, and the mixed granulation powder enters the focused light spot area, spheroidizes and reacts under the high energy density beam to obtain spherical titanium carbide powder with a particle size of 53-105 μm.

[0063] The spherical titanium carbide powder prepared in the above embodiment 1 was tested, and the spheroidization rate of the titanium carbide powder in the above method was 93.2%, and the SEM image of the spherical titanium carbide powder is shown in Figure 2 .

[0064] The spheroidization rate is tested according to YS / T1296-2019 “Determination of Titanium and Titanium Alloy Powder Morphology”.

[0065] Example 2

[0066] A method for preparing spherical titanium carbide powder, the steps are as follows:

[0067] (1) Mix TiO2 powder with a particle size of 10-25 μm and carbon black with a particle size of 20-53 μm at a molar ratio of 1:1, use a planetary ball mill for ball milling, the rotation speed is 11800 rad / min, the time is 20 h, and the ball-to-material ratio is 26:1;

[0068] (2) Spray granulation is carried out by using a spray granulator to obtain mixed granulation powder of TiO2 and carbon black with a particle size of 74-145 μm;

[0069] (3) The reaction chamber is vacuumed to 0.1 pa, argon is introduced from the protective gas inlet of the laser spheroidization equipment, the laser generator and the auxiliary equipment are turned on, and a stable laser beam with a focused light spot area is formed, wherein the operating parameters of the laser spheroidization equipment are set as follows: the flow rate of argon is 2.5 L / min, the laser power is 4.5 kW, and the spot diameter is 4.5 mm;

[0070] (4) Turn on the powder feeder, control the powder gas flow to be 3.8 L / min and the powder feeding rate to be 15 g / min, and the mixed granulation powder enters the focused light spot area, spheroidizes and reacts under the high energy density beam to obtain spherical titanium carbide powder with a particle size of 53-105 μm.

[0071] The spherical titanium carbide powder prepared in the above embodiment 2 was tested, and the spheroidization rate of the titanium carbide in the above method was 94.3%, and the SEM image of the spherical titanium carbide powder is shown in Figure 3 .

[0072] The spheroidization rate is tested according to YS / T1296-2019 “Determination of Titanium and Titanium Alloy Powder Morphology”.

[0073] Example 3

[0074] A method for preparing spherical titanium carbide powder, comprising the following steps:

[0075] (1) TiO2 powder with a particle size of 10-25 μm and carbon black with a particle size of 20-53 μm are mixed at a molar ratio of 1:1, and ball milling is performed using a planetary ball mill at a rotation speed of 11800 rad / min for 20 h, with a ball-to-material ratio of 26:1;

[0076] (2) Spray granulation is performed using a spray granulator to obtain mixed granulated powder of TiO2 and carbon black with a particle size of 74-145 μm;

[0077] (3) The reaction chamber is evacuated to 0.1 Pa, argon is introduced from the protective gas inlet of the laser spheroidization device, the laser generator and the auxiliary equipment are turned on, and a stable laser beam with a focused spot area is formed, wherein the operating parameters of the laser spheroidization device are set as follows: the flow rate of argon is 2.5 L / min, the laser power is 6.0 kW, and the spot diameter is 6.5 mm;

[0078] (4) The powder feeder is turned on, and the mixed granulated powder enters the focused spot area at a powder feeding gas flow rate of 3.8 L / min and a powder feeding rate of 17 g / min, and is spheroidized and reacted under a high-energy-density beam to obtain spherical titanium carbide powder with a particle size of 53-105 μm.

[0079] The spherical titanium carbide powder prepared in Example 3 is tested, and the spheroidization rate of the titanium carbide in the above method is 91.1%, and the SEM image of the spherical titanium carbide powder is as shown in Figure 4 .

[0080] The spheroidization rate is tested according to YS / T 1296-2019 “Determination of the Morphology of Titanium and Titanium Alloy Powder”.

[0081] In addition, the Vickers hardness of the titanium carbide powder prepared in Examples 1-3 is tested, and the results are shown in Table 1.

[0082] Table 1 Vickers hardness of spherical titanium carbide powder changes with temperature

[0083] Temperature (°C) 20 300 500 Example 1 Vickers Hardness (HV0.1) 3198 3192 3156 Example 2 Vickers Hardness (HV0.1) 3205 3201 3174 Example 3 Vickers Hardness (HV0.1) 3182 3180 3140

[0084] As can be seen from Table 1, the Vickers hardness of the spherical titanium carbide powder prepared by the present application ranges from 3205 (HV0.1) to 3140 (HV0.1) at 20-500°C, and has high red hardness.

[0085] In summary, the application adopts TiO2 and carbon black as raw materials, and adopts mixing-granulating-laser spheroidization to prepare spherical titanium carbide powder, so that the production process is simplified and the production cost is reduced.

[0086] The above merely describes preferred embodiments of the present application, but is not intended to limit the scope of the application; if the application is modified or replaced equivalently without departing from the spirit and scope of the application, it should be covered in the protection scope of the claims of the application.

Claims

1. A method for preparing spherical titanium carbide powder, characterized in that, It is prepared using a laser spheroidization device, specifically including the following steps: 1) Ball mill and mix TiO2 powder and carbon black in a molar ratio of 1:1; the particle size of TiO2 powder is 10-25 μm and the particle size of carbon black is 20-53 μm; 2) Spray granulation to obtain a mixed granulated powder of TiO2 powder and carbon black; the nozzle speed during spray granulation is 11800 rad / min, and the particle size of the mixed granulated powder is 74-145 μm; 3) Beam initiation: The reaction chamber is evacuated to below 0.1 Pa, and argon gas is introduced through the protective gas inlet of the laser spheroidizing device. The laser generator and auxiliary equipment are turned on to form a stable laser beam with a focused spot area. The power of the laser generator is 2.0-6.0 kW, and the spot diameter in the focused spot area is 3.5-6.5 mm. 4) Powder feeding: Turn on the powder feeder, control the powder feeding gas flow rate and powder feeding rate, and feed the mixed granulated powder into the laser beam. Sphericalization and reaction are carried out in the focused spot area of ​​the laser beam to prepare spherical titanium carbide powder. The powder feeding gas is argon with a purity ≥99.999%, the powder feeding gas flow rate is 3.8 L / min, and the powder feeding rate is 13-17 g / min.

2. The method for preparing spherical titanium carbide powder according to claim 1, characterized in that, In step 1), argon gas is used for protection during the ball milling process, the ball milling speed is 180 rad / min, the time is 20 h, and the ball-to-material ratio is 26:

1.

3. The method for preparing spherical titanium carbide powder according to claim 1, characterized in that, In step 3), the purity of argon gas is ≥99.999%, and the flow rate of argon gas is 2.5 L / min.

4. The method for preparing spherical titanium carbide powder according to claim 2, characterized in that, In step 4), the particle size of the titanium carbide powder prepared is 53-105 μm.

5. The method for preparing spherical titanium carbide powder according to claim 1, characterized in that, The laser beam is a high-energy-density beam.

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