CN114289722B - Preparation method of fine-grained spherical tungsten powder - Google Patents
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Abstract
A preparation method of fine-grained spherical tungsten powder belongs to the technical field of powder metallurgy. Aiming at the problems of large particle size, wide powder particle size distribution and low yield after spheroidization in the spheroidization process due to irregular morphology of raw material fine-particle tungsten powder and easy agglomeration at present, the invention firstly adopts fluidized bed treatment to improve the powder state of tungsten powder, improves the dispersibility of the powder and changes the surface morphology of the powder. And then the treated powder is sent into a powder feeding device, pressure is applied to form a plasma torch, and the powder is spheroidized. Finally, the spherical tungsten powder with smooth surface and high spheroidization rate is obtained. The invention combines the fluidization and dispersion technology and the plasma spheroidization technology to prepare the fine-grained spherical tungsten powder, and the spheroidized tungsten powder has low activity, no pollution, good sphericity, full spheroidization and high yield.
Description
Technical Field
The invention belongs to the technical field of powder metallurgy, and particularly relates to a preparation method of fine-grained spherical tungsten powder.
Background
Tungsten and tungsten alloys have the excellent performances of high melting point, high-temperature strength, good heat resistance and corrosion resistance and the like, and are widely applied to the fields of aerospace, nuclear power, medical treatment and the like. The traditional powder metallurgy method is difficult to prepare tungsten with complex structure and alloy products thereof. With the continued development of material forming techniques, 3D printing and powder injection forming techniques are effective methods of preparing small tungsten and their alloy articles. As a raw material for preparing tungsten product pieces with complex structures by 3D printing and powder injection molding, the preparation of spherical tungsten powder is an important link for developing novel tungsten and alloy products thereof. The method for preparing the spherical tungsten powder is endless, such as a halogenation method, a rotating electrode method, a partial preferential oxidation-alkali washing method, an ammonium paratungstate circulating oxidation-reduction method, a spray drying method and the like, and the method has various defects and cannot realize industrialization. Therefore, the preparation process of the spherical tungsten powder with simple process and low cost is very necessary.
The plasma spheroidization has the advantages of high energy density, high heating strength, no pollution and the like, has good effect on the treatment of refractory metal powder such as tungsten and the like, and can obtain spherical powder with good sphericity, high spheroidization rate and high purity. Since the agglomeration of the commercial fine-grained tungsten powder is serious, the granularity and granularity distribution of the powder obtained after the radio-frequency plasma spheroidization treatment are mainly determined by the granularity and granularity distribution of the feed powder, in this case, the spheroidization rate of the powder is improved by improving the power, so that the fine-grained spherical tungsten powder is gasified and disappears in the process, the median diameter of the powder is increased, the granularity distribution of the powder obtained after the plasma spheroidization treatment is wide, and the powder is easy to aggregate and grow. The fluidization dispersion treatment can realize deagglomeration, crushing refinement and surface shaping of the powder, improves loose loading, tap density and the like of the powder, and has the advantages of low energy consumption, small abrasion and the like. Chinese patent (CN 104070173B) discloses a method for preparing spherical tungsten powder, which comprises grinding tungsten powder with particle size of 5-27 μm in an air flow mill, and spheroidizing with an argon plasma torch to obtain spherical tungsten powder, wherein the spheroidized tungsten powder has larger particle size, uneven distribution and low spheroidization rate due to agglomeration. Chinese patent (CN 104174862B) discloses a preparation method of spherical tungsten powder which is low in cost, easy to produce in a large scale and easy to control parameters, but the prepared powder has uneven granularity, poor sphericity and easy to pollute, and fine spherical tungsten powder is difficult to obtain. Therefore, the invention adopts the combination of the fluidization and dispersion technology and the plasma spheroidization technology to prepare the fine-grained spherical tungsten powder, and the spheroidized tungsten powder has low activity, no pollution, good sphericity, full spheroidization and high yield.
Disclosure of Invention
Aiming at the problems of large particle size, wide powder particle size distribution and low yield of the spheroidized tungsten powder caused by irregular and easy agglomeration of the tungsten powder with fine particle size in the prior art, the invention adopts the combination of a fluidization dispersion technology and a plasma spheroidization technology to prepare the spherical tungsten powder.
A preparation method of spherical tungsten powder is characterized in that a counter-jet mill dispersion technology and a plasma spheroidization technology are combined to prepare spherical tungsten powder;
the method comprises the following specific steps:
1) The raw material powder is tungsten powder with the purity of more than 99.9 percent and the granularity of less than 3 mu m;
2) The raw material powder is added into a fluidized bed, high-purity inert gas is firstly filled into the equipment from bottom to top to remove air before dispersion treatment, gas protection environment is provided for the powder, and the equipment is inflated and cleaned; after the air in the cavity of the fluidized bed is exhausted, transferring the air into a heating device, continuously introducing high-purity hydrogen gas with stable flow in the fluidized bed treatment process, and carrying out fluidization treatment for a certain time at constant flow and constant temperature;
3) After the dispersion treatment of the fluidized bed, removing the cavity of the fluidized bed from the heating device, continuously introducing high-purity inert protective gas, and stopping introducing the protective gas after cooling to room temperature to obtain treated powder;
4) Calcining the powder treated in the step 3) for one time or more times at the temperature of 200-450 ℃ under the protective atmosphere of high-purity hydrogen with the purity of more than 99.9%;
5) Sending the treated powder into a powder feeding device, taking argon as working gas, applying pressure to form a plasma torch, and performing spheroidization on the powder;
6) And cooling the powder subjected to plasma spheroidization, and collecting to obtain the treated powder.
Further, the flow rate of the hydrogen gas flow in the step 2) is 1.5-5L/min, the heating temperature is 150-280 ℃, and the fluidization treatment is carried out for 100-360 min under constant flow and constant temperature.
Further, the calcination treatment process in step 4) is as follows: the temperature rising rate is 1-2 ℃/min, the heat preservation time is 60-300 min, and the temperature reducing rate is 2-5 ℃/min.
Further, the spheroidizing treatment in the step 5) is performed, wherein the powder feeding rate is 10-18 g/min, the treatment power is 10-35 kw, the powder feeding air flow is 8-15L/min, the medium air flow is 35-50L/min, and the side air flow is 30-75L/min.
The invention has the advantages that:
(1) The fluidization treatment is carried out under the high-purity inert and hydrogen atmosphere, and due to the action of air flow, collision and friction occur between the powder and the inner wall of the cavity of the fluidized bed, so that agglomeration among particles is opened, the surface morphology of the particles is changed, and no pollution is caused;
(2) After fluidization dispersion treatment, tungsten powder is agglomerated and opened, the fluidity is improved, and the loose tap density is improved;
(3) After the powder after fluidization treatment is calcined, the internal stress generated in the fluidization process can be eliminated, the powder activity is reduced, and the particle growth can be avoided in the subsequent plasma spheroidization process;
(4) The energy density in the plasma spheroidizing process is high, the heating strength is high, the purity of the obtained powder is high, the spheroidization rate is high, the sphericity is good, and the method is suitable for the treatment of refractory metal powder;
(5) The tungsten powder after fluidization and dispersion treatment is subjected to radio frequency plasma spheroidization, and the aggregation growth of agglomerate particles can be effectively avoided due to better fluidity of the tungsten powder, so that the spheroidized tungsten powder has good sphericity, full spheroidization and high yield.
Drawings
Fig. 1 is an XRD pattern of tungsten powder before and after fluidization-plasma spheroidization.
Detailed Description
Example 1
1) The raw material powder is commercial tungsten powder, the granularity is 2 mu m, and the purity is more than 99.9%;
2) The raw material powder is added into a fluidized bed, high-purity inert gas is firstly filled into the equipment from bottom to top to remove air before dispersion treatment, gas protection environment is provided for the powder, and the equipment is inflated and cleaned; after the air in the cavity of the fluidized bed is exhausted, transferring the air into a heating device, continuously introducing high-purity inert gas with stable flow in the fluidized bed treatment process, wherein the flow speed of the gas flow is 5L/min, the heating temperature is 250 ℃, and carrying out fluidization treatment for 180min at constant flow and constant temperature;
3) After the dispersion treatment of the fluidized bed, removing the cavity of the fluidized bed from the heating device, continuously introducing high-purity inert protective gas, and stopping introducing the protective gas after cooling to room temperature to obtain treated powder;
4) Heating the fluidized powder to 400 ℃ at a speed of 1 ℃/min under the condition that high-purity hydrogen with purity of more than 99.9% is used as a protective atmosphere, and performing twice calcination treatment at a temperature-reducing speed of 3 ℃/min in a heat-preserving 60 min;
5) Feeding the treated powder into a powder feeding device, using argon as working gas, applying pressure to form a plasma torch, and performing spheroidizing treatment on the powder, wherein the powder feeding speed is 15g/min, the treatment power is 30kw, the powder feeding air flow is 15L/min, the middle air flow is 50L/min, and the side air flow is 75L/min;
6) And cooling and collecting the powder after plasma treatment to obtain spherical tungsten powder with the particle size distribution concentrated at about 2 mu m, the spheroidization rate being close to 100% and the sphericity being good.
Example 2
1) The raw material powder is commercial tungsten powder, the granularity is 1 mu m, and the purity is more than 99.9%;
2) The raw material powder is added into a fluidized bed, high-purity inert gas is firstly filled into the equipment from bottom to top to remove air before dispersion treatment, gas protection environment is provided for the powder, and the equipment is inflated and cleaned; after the air in the cavity of the fluidized bed is exhausted, transferring the air into a heating device, continuously introducing high-purity hydrogen gas with stable flow in the fluidized bed treatment process, wherein the flow speed of the gas flow is 4L/min, the heating temperature is 200 ℃, and carrying out fluidization treatment for 120min at constant flow and constant temperature;
3) After fluidization and dispersion treatment, the fluidized bed cavity is removed from the heating device, and high-purity inert shielding gas is continuously introduced, and after the fluidized bed cavity is cooled to room temperature, the shielding gas is stopped to obtain treated powder.
4) Heating the fluidized powder to 300 ℃ at a speed of 2 ℃/min under the condition that high-purity hydrogen with the purity of more than 99.9% is used as a protective atmosphere, and performing primary calcination treatment at a temperature-reducing speed of 4 ℃/min after heat preservation for 90 min;
5) Feeding the treated powder into a powder feeding device, using argon as working gas, applying pressure to form a plasma torch, and performing spheroidizing treatment on the powder, wherein the powder feeding speed is 12g/min, the treatment power is 25kw, the powder feeding air flow is 10L/min, the middle air flow is 45L/min, and the side air flow is 65L/min;
6) And cooling and collecting the powder after plasma spheroidization to obtain spherical tungsten powder with the particle size distribution concentrated at about 1 mu m, the spheroidization rate being close to 100% and the sphericity being good.
Example 3
1) The raw material powder is commercial tungsten powder, the granularity is 0.8 mu m, and the purity is more than 99.9%;
2) The raw material powder is added into a fluidized bed, high-purity inert gas is firstly filled into the equipment from bottom to top to remove air before dispersion treatment, gas protection environment is provided for the powder, and the equipment is inflated and cleaned; after the air in the cavity of the fluidized bed is exhausted, the air is transferred to a heating device, high-purity hydrogen gas with stable flow is continuously introduced in the treatment process of the fluidized bed, the flow speed of the gas flow is 3L/min, the heating temperature is 180 ℃, and the fluidization treatment is carried out for 100min at constant flow and constant temperature.
3) After fluidization and dispersion treatment, the fluidized bed cavity is removed from the heating device, and high-purity inert shielding gas is continuously introduced, and after the fluidized bed cavity is cooled to room temperature, the shielding gas is stopped to obtain treated powder.
4) Heating the fluidized powder to 250 ℃ at a speed of 1 ℃/min under the condition that high-purity hydrogen with purity of more than 99.9% is used as a protective atmosphere, and performing primary calcination treatment at a temperature-reducing speed of 2 ℃/min after heat preservation for 120min;
5) Feeding the treated powder into a powder feeding device, using argon as working gas, applying pressure to form a plasma torch, and performing spheroidizing treatment on the powder, wherein the powder feeding speed is 10g/min, the treatment power is 25kw, the powder feeding air flow is 8L/min, the middle air flow is 40L/min, and the side air flow is 60L/min;
6) After spheroidizing: and cooling and collecting the powder after plasma spheroidization to obtain spherical tungsten powder with the particle size distribution concentrated at about 0.8 mu m, the spheroidization rate being close to 100% and the sphericity being good.
While the invention has been described with respect to preferred embodiments, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention, and that any such changes and modifications as described in the above embodiments are intended to be within the scope of the invention.
Claims (2)
1. A preparation method of spherical tungsten powder is characterized in that a counter-jet mill dispersion technology and a plasma spheroidization technology are combined to prepare spherical tungsten powder;
the method comprises the following specific steps:
1) The raw material powder is tungsten powder with the purity of more than 99.9 percent and the granularity of less than 3 mu m;
2) The raw material powder is added into a fluidized bed, high-purity inert gas is firstly filled into the equipment from bottom to top to remove air before dispersion treatment, gas protection environment is provided for the powder, and the equipment is inflated and cleaned; after the air in the cavity of the fluidized bed is exhausted, transferring the air into a heating device, continuously introducing high-purity hydrogen gas with stable flow in the fluidized bed treatment process, and carrying out fluidization treatment for a certain time at constant flow and constant temperature;
3) After the dispersion treatment of the fluidized bed, removing the cavity of the fluidized bed from the heating device, continuously introducing high-purity inert protective gas, and stopping introducing the protective gas after cooling to room temperature to obtain treated powder;
4) Calcining the powder treated in the step 3) for one time or more times at the temperature of 200-450 ℃ under the protective atmosphere of high-purity hydrogen with the purity of more than 99.9%;
5) Sending the treated powder into a powder feeding device, taking argon as working gas, applying pressure to form a plasma torch, and performing spheroidization on the powder;
6) Cooling the powder subjected to plasma spheroidization, and collecting to obtain treated powder;
the calcination treatment process in the step 4) comprises the following steps: the temperature rising rate is 1-2 ℃/min, the heat preservation time is 60-300 min, and the temperature reducing rate is 2-5 ℃/min;
the flow rate of the hydrogen gas flow in the step 2) is 1.5-5L/min, the heating temperature is 150-280 ℃, and the fluidization treatment is carried out for 100-360 min under constant flow and constant temperature.
2. The method for producing spherical tungsten powder according to claim 1, wherein the spheroidizing in step 5) is performed at a powder feeding rate of 10 to 18g/min, a treatment power of 10 to 35kw, a powder feeding gas flow rate of 8 to 15L/min, a medium gas flow rate of 35 to 50L/min, and a side gas flow rate of 30 to 75L/min.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62282635A (en) * | 1986-05-31 | 1987-12-08 | Natl Res Inst For Metals | Production of mixture of ultra-fine aluminum nitride powder and ultra-fine oxidation-resistant aluminum powder |
| CN104070173A (en) * | 2014-06-23 | 2014-10-01 | 陕西斯瑞工业有限责任公司 | Preparation method of spherical tungsten powder |
| KR20150031750A (en) * | 2013-09-16 | 2015-03-25 | 한국생산기술연구원 | Method for manufacturing powder of ruthenium-chromium with rf plasma process |
| CN107470639A (en) * | 2017-09-18 | 2017-12-15 | 北京科技大学 | A kind of preparation method of narrow size distribution globular tungsten powder |
| CN109382511A (en) * | 2018-11-23 | 2019-02-26 | 北京科技大学 | A kind of fluidisation shaping preparation method of 3D printing Low cost technique of titanium powders |
| CN112453413A (en) * | 2020-11-20 | 2021-03-09 | 中科院过程工程研究所南京绿色制造产业创新研究院 | Preparation method of oxide dispersion strengthened steel spherical powder for 3D printing |
-
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- 2021-12-08 CN CN202111494192.2A patent/CN114289722B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62282635A (en) * | 1986-05-31 | 1987-12-08 | Natl Res Inst For Metals | Production of mixture of ultra-fine aluminum nitride powder and ultra-fine oxidation-resistant aluminum powder |
| KR20150031750A (en) * | 2013-09-16 | 2015-03-25 | 한국생산기술연구원 | Method for manufacturing powder of ruthenium-chromium with rf plasma process |
| CN104070173A (en) * | 2014-06-23 | 2014-10-01 | 陕西斯瑞工业有限责任公司 | Preparation method of spherical tungsten powder |
| CN107470639A (en) * | 2017-09-18 | 2017-12-15 | 北京科技大学 | A kind of preparation method of narrow size distribution globular tungsten powder |
| CN109382511A (en) * | 2018-11-23 | 2019-02-26 | 北京科技大学 | A kind of fluidisation shaping preparation method of 3D printing Low cost technique of titanium powders |
| CN112453413A (en) * | 2020-11-20 | 2021-03-09 | 中科院过程工程研究所南京绿色制造产业创新研究院 | Preparation method of oxide dispersion strengthened steel spherical powder for 3D printing |
Non-Patent Citations (1)
| Title |
|---|
| 射频感应等离子体制备球形钨粉的工艺研究;古忠涛;叶高英;刘川东;童洪辉;;强激光与粒子束(第07期);第1079-1082页 * |
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