CN115365491A - Efficient powder premixing process - Google Patents
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/10—Metallic powder containing lubricating or binding agents; Metallic powder containing organic material
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F1/00—Metallic powder; Treatment of metallic powder, e.g. to facilitate working or to improve properties
- B22F1/14—Treatment of metallic powder
- B22F1/148—Agglomerating
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/02—Making metallic powder or suspensions thereof using physical processes
- B22F9/06—Making metallic powder or suspensions thereof using physical processes starting from liquid material
- B22F9/08—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying
- B22F9/082—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid
- B22F2009/0844—Making metallic powder or suspensions thereof using physical processes starting from liquid material by casting, e.g. through sieves or in water, by atomising or spraying atomising using a fluid in controlled atmosphere
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Abstract
The invention relates to a high-efficiency powder premixing process, which comprises the steps of identifying the thickness of each powder to be mixed, and crushing and grinding the coarsest powder in advance to enable the particle size to be close to the average value of the whole powder; distinguishing the weight, namely distinguishing the weight of each powder needing to be mixed, and grinding and refining the heaviest powder; drying and dehumidifying, namely drying and dehumidifying all the powder to be mixed; detecting the fluidity, namely detecting the fluidity of all the powder to be mixed by using a powder stacking angle; heating treatment, namely heating treatment is carried out on the raw material powder; annealing treatment, wherein the annealing temperature is controlled to be 50 to 60 percent of the absolute temperature of the melting point of the annealing treatment and is carried out in vacuum; mixing, namely mixing all the powder to be mixed, and adding a lubricant in the mixing process; spray drying granulation, namely preparing the mixed small particle powder into large particle powder or granules, adjusting the indexes of the large particle powder or granules to be relatively close by a pretreatment method, and then mixing, so that the mixing process is more efficient, and the quality of the mixed powder is higher.
Description
Technical Field
The invention relates to the technical field of metal powder pretreatment processes, in particular to a high-efficiency powder premixing process.
Background
Powder metallurgy is a process technology for preparing metal or metal powder (or a mixer of metal powder and nonmetal powder) as a raw material, and manufacturing metal materials, composites and various products through forming and sintering, wherein the uniformity of powder mixing cannot meet the requirement due to the influence of the self characteristics of the powder in the powder metallurgy production mixing process; the density of metal powder is different from that of ceramic and plastic, so that the problems of large difference of light powder and heavy powder and difficult mixing are most easily caused, in the powder mixing process, the heavy powder is definitely sunk below, and the light powder always floats above, and in the condition, a three-dimensional mixer or a V-shaped mixer with a half rotating by a charging barrel is difficult to solve.
The publication number of grant CN202010866393.X discloses a preparation method of graphene-aluminum mixed powder, which comprises the steps of pretreating graphene and aluminum metal powder, only adding a mixed solution to carry out pretreatment in the pretreatment process, and sensitizing the surface of the aluminum metal powder by using an aqueous solution of tin chloride to enable the surface of the aluminum metal powder to adsorb cations and carry positive charges; treating the surface of the graphene by ammonia water to enable the surface of the graphene to adsorb anions and to be negatively charged; then mixing the pretreated aluminum powder and graphene, performing ultrasonic stirring and dispersion, and finally performing vacuum filtration and drying to obtain graphene-aluminum mixed powder, wherein the method has the following problems: firstly, the pertinence is too strong, most of powder is not suitable for mixing pretreatment, and then the subsequent conveying treatment step is not considered in the final vacuum filtration and drying process, the process method is not perfect, and the pretreatment time is determined according to the reaction speed, so that the efficiency is not high enough.
Disclosure of Invention
Aiming at the defects of the prior art, the invention firstly distinguishes the weight and the thickness of the powder in the powder pretreatment stage, and then carries out proper pretreatment on the powder according to the self characteristics of the powder, thereby solving the technical problem of being applicable to various powders needing to be mixed.
In order to achieve the purpose, the invention provides the following technical scheme:
a high-efficiency powder premixing process comprises the following steps of S1: thickness discrimination, namely discriminating the thickness of each powder to be mixed, and crushing and grinding the coarsest powder in advance to enable the particle size to be close to the average value of the whole powder;
s2: distinguishing the weight, namely distinguishing the weight of each powder needing to be mixed, and grinding and refining the heaviest powder;
s3: drying and dehumidifying, namely drying and dehumidifying all the powder to be mixed;
s4: detecting the fluidity, namely detecting the fluidity of all the powder to be mixed by using a powder stacking angle;
s5: heating treatment, namely heating treatment is carried out on the raw material powder;
s6: annealing treatment, wherein the annealing temperature is controlled to be 50 to 60 percent of the absolute temperature of the melting point of the annealing treatment and is carried out in vacuum;
s7: mixing, namely mixing all the powder to be mixed, and adding a lubricant in the mixing process;
s8: spray drying and granulating, and making the mixed small granule powder into large granule powder or granule.
Preferably, the spray drying granulation method in the step S8 comprises
(1) Dripping paraffin wine liquid;
(2) Stirring until the powder content is 75-80% and uniform slurry is obtained;
(3) Conveying nitrogen;
(4) Spraying in an atomizing tower;
(5) Atomizing to form spherical paddle drops;
(6) Hot nitrogen treatment is carried out to form fine spherical or pear-shaped aggregates;
(7) And (4) collecting and conveying.
Preferably, the mixing in step S7 is a double-motion mixer, and the internal blade tip linear speed is lower than 200 m/min, and the motion speed is moderate.
Preferably, the steps S1, S2 and S3 can be performed simultaneously, and the powders to be mixed are placed in a container capable of being heated at an elevated temperature, and physically ground until the particle size is relatively uniform by visual observation.
Preferably, the angle of the stacking angle in the step S4 is less than 40 degrees, and when the step S1, the step S2 and the step S3 are performed simultaneously, the stacking angle of the powder mixed with the powder is detected to determine whether dry powder with poor flowability exists, and if dry powder with poor flowability exists, the drying and dehumidifying processing time in the step S3 is prolonged.
Preferably, a specific binder is added in the process of stirring the uniform slurry, and then the mixed powder can be compacted, packaged and conveyed by a powder blank pressing method in the collecting and conveying process.
Preferably, the step S5 and the step S6 are both performed in a reducing atmosphere, the reducing atmosphere is a mixed gas of hydrogen and nitrogen, the step S5 heat treatment process is placed in a vacuum furnace, the temperature is controlled between 60 ℃ and 350 ℃, the time is controlled between 0.5 hours and 3 hours, and the step S6 annealing treatment is performed in a reducing annealing furnace, and the temperature is controlled between 500 ° and 1000 °.
Preferably, the heavier coarse powder is ground in step S1 and step S2 by wet grinding, and industrial alcohol is added for grinding.
Preferably, the step S1 and the step S2 are performed with a pre-passivation treatment for some ultra-fine powders.
As still another preference, after all of steps S1 to S4 are completed, the powder is directly conveyed to a furnace of the heating treatment by a belt conveyor.
The invention has the beneficial effects that:
(1) According to the invention, through distinguishing the weight and the thickness of the powder in the early stage, a worker can perform targeted treatment when pretreating the powder, so that the subsequent mixing is more uniform, the mixing efficiency is higher, and the method is suitable for the mixing pretreatment step of various powders.
(2) In the invention, the powder is preheated through heating treatment and annealing treatment, so that the oxide is reduced, the content of carbon and other impurities is reduced, the purity of the powder is improved, the work hardening of the powder in the treatment process is eliminated, the compressibility of the powder is improved, and the annealing treatment is carried out on the powder, so that the stress between powder mixtures is released, the ductility and the toughness of the powder are increased, and a special microstructure is generated.
(3) The invention performs granulation while drying the slurry by spray drying granulation, saves time and improves efficiency, and the material particles are soft, uniform in granularity, convenient to transport, easy to control the granularity, the loose density and the dry and wet degree of the material particles, short in drying granulation time, less in dirtying and capable of realizing continuous automation in production.
In conclusion, the process has the advantages of simplicity, high efficiency and suitability for mixing of various powders, and is particularly suitable for the technical field of metal powder pretreatment processes.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic diagram of the overall mixed powder process framework of the present invention.
Fig. 2 is a schematic diagram of a flow chart in the present invention in which steps S1 to S4 can be simultaneously performed for some specific powders.
FIG. 3 is a schematic block diagram of a process for spray drying granulation in accordance with the present invention;
fig. 4 is a frame diagram of the targeted pretreatment process for ultra-fine powder and over-heavy powder in the present invention.
Detailed Description
The technical scheme in the embodiment of the invention is clearly and completely explained by combining the attached drawings.
Example one
As shown in FIGS. 1 to 3, the present invention provides a highly efficient premixing process for powders, comprising the steps of
S1: the thickness identification, namely identifying the thickness of each powder to be mixed, carrying out crushing and grinding on the coarsest powder in advance to enable the particle size to be close to the average value of the whole powder, and manually carrying out pre-identification aiming at different powder mixtures, so that large-particle powder which can be observed by naked eyes is ground in advance, and the method is simple and efficient;
s2: the weight discrimination is to discriminate the weight of each powder to be mixed, grind and refine the heaviest powder, weigh the powder by using a weighing meter and grind the heavier powder in advance, so that the method is convenient and fast;
s3: drying and dehumidifying, namely drying and dehumidifying all the powder to be mixed;
s4: detecting the fluidity, namely detecting the fluidity of all the powder to be mixed by using a powder stacking angle;
s5: heating treatment, namely heating treatment is carried out on the raw material powder;
s6: annealing treatment, wherein the annealing temperature is controlled to be 50 to 60 percent of the absolute temperature of the melting point of the annealing treatment and is carried out in vacuum;
s7: mixing, namely mixing all the powder to be mixed, and adding a lubricant in the mixing process;
s8: spray drying and granulating, and making the mixed small granule powder into large granule powder or granule.
Further, as shown in fig. 3, the method of spray drying granulation in step S8 comprises
(1) Dripping paraffin wine liquid;
(2) Stirring until the powder content is 75 to 80 percent, and obtaining uniform slurry;
(3) Conveying nitrogen;
(4) Spraying in an atomizing tower;
(5) Atomizing to form spherical paddle drops;
(6) Hot nitrogen treatment is carried out to form fine spherical or pear-shaped aggregates;
(7) And (4) collecting and conveying.
Further, the mixing in the step S7 adopts a double-motion mixer, and the linear velocity of the blade tips of the blades inside the double-motion mixer is lower than 200 m/min, the moving speed is moderate, the double-motion mixer is used for mixing materials while the device driver moves, and simultaneously the full-size blades in the container are driven to move at a higher speed to stack and mix the materials, wherein the floating ultrafine powder can be wrapped and carried into the main powder by the rotation of the container and the rotation of the blades, and meanwhile, the adsorption and polymerization phenomena of the ultrafine powder can be prevented and broken up by the shearing action of the blades inside the powder, and the shearing force capable of opening and breaking up the adhesive force between the fine powders can be possessed during the mixing, so that the mixing effect is more uniform, the agglomeration phenomenon caused by unnecessary static electricity between the powders is reduced, the efficiency of the powder pretreatment is improved, and the hands of workers are liberated, and the automation is realized;
and if the linear speed of the tip of the high-speed rotating blade is higher than 200 m/min to hit the powder, the original appearance of the powder is damaged, so that the mixing process is influenced and the internal chemical composition fluctuates, and the quality of powder mixing can be better controlled by controlling the speed.
Further, as shown in fig. 2, the steps S1, S2 and S3 can be performed simultaneously, the powders to be mixed are placed in a container capable of being heated at an elevated temperature, and are physically ground until the particle sizes are relatively uniform, in the step S1, the powders are subjected to thickness discrimination, the powder with the coarsest particle size can be seen by naked eyes, and grinding is performed to adjust the particle size of the whole powders to be mixed;
the step S2 is to distinguish the weight of the powder, the powder can be observed obviously only by placing the powder on a weighing platform, then the heaviest powder is ground, because the light powder and the heavy powder with great specific gravity difference are not easy to be mixed uniformly, after the heavy powder is refined, the occupied space of the light powder and the heavy powder is enlarged, namely the loose specific gravity is reduced, and the single particle is light, thereby reducing the sinking power and improving the mixing effect;
step S3 is that some mixed powder is too moist, the mobility is poor, the mixing is not easy to be uniform, and the powder is easy to be combined into granules in the mixing process, if the powder exists, the powder needs to be dried and dehumidified in advance, the mobility is improved, and in the step S1 and the step S2, liquid is added in the grinding process to be wet-ground, so that the environment can be protected, no dust flies, the noise is reduced, the crushing efficiency is improved, the refining of powder particles is facilitated, the powder can be protected from being oxidized, the wetting influence can be caused to the powder in the method, the step S3 can be used for drying the whole body, and the drying and the dehumidifying can be carried out simultaneously, the uniformity of the powder mixing can not be influenced, the time can be saved, the cost can be saved, and the drying and the dehumidifying process can be dried more thoroughly.
Further, the angle of the powder stacking angle in the step S4 is smaller than 40 degrees, and when the step S1, the step S2 and the step S3 are performed simultaneously, the powder stacking angle detection is performed on the relatively mixed powder to judge whether dry powder with poor flowability exists, if dry powder with poor flowability exists, the drying and dehumidifying processing time in the step S3 is prolonged, after the particle diameter and the loose specific gravity of the powder are adjusted, the last observation needs to be performed, the flowability of the powder is observed by using the powder stacking angle, the smaller the powder stacking angle is, the smoother the powder is, the better the flowability is, and when the powder stacking angle is larger than 40 degrees, the flowability starts to be deteriorated, no matter what powder is, the powder stacking angle needs to be controlled to be below 40 degrees;
for the powder with poor fluidity, the drying time is prolonged, if the powder is poor in fluidity by nature, the problem that the drying cannot be solved is that a specific binder is added during powder mixing, so that various addition elements in the mixed powder can be uniformly dispersed and fixed on matrix iron powder, the powder fluidity can be improved, the powder pollution and component segregation are reduced, the carbon loss is reduced or avoided, the overall quality control capability, the powder compressibility and the green strength are improved, the fluctuation of chemical components of the powder to be pressed is reduced, and the physical property difference between the interior of a powder metallurgy part and the part is reduced.
Furthermore, a specific binder is added in the process of uniformly stirring the slurry, then the mixed powder can be compacted, packaged and conveyed by adopting a powder blank pressing method in the collecting and conveying process, and the specific binder is also added in the final conveying process because the pressed powder can cause fluctuation of internal chemical components, so that the phenomenon of uneven powder distribution caused by scattering of the mixed powder in the conveying process can be avoided, and the use of subsequent processes is influenced.
Further, the step S5 and the step S6 are both performed in a reducing atmosphere, the reducing atmosphere is a mixed gas of hydrogen and nitrogen, the step S5 is performed in a vacuum furnace, the temperature is controlled between 60 ℃ and 350 ℃, the time is controlled between 0.5 hour and 3 hours, the step S6 is performed in a reducing annealing furnace, the temperature is controlled between 500 ° and 1000 °, the temperature in the heating process is limited, a universal furnace can be used for most of the mixed powder, the application range is wider, the temperature in the annealing process is so high as to improve the chemical purity of the powder, and the step S5 and the step S6 are performed in the reducing atmosphere, so that the oxidation reaction does not occur, and the quality of the mixed powder is damaged.
Further, as shown in fig. 4, in the step S1 and the step S2, a wet grinding method is adopted for grinding the heavier and coarser powder, and industrial alcohol is added for grinding, the wet grinding method is favorable for environmental protection, prevents the powder from flying apart during grinding, affects the working environment, reduces noise generation during grinding, improves grinding efficiency, is powerful and fine with the powder, and can also play a role in protecting the powder from oxidation during grinding.
Further, as shown in fig. 4, the passivation process is performed on some of the ultrafine powders in the steps S1 and S2, the passivation process is performed on some of the ultrafine powders, when the powders are refined to a certain degree, physical properties of the powders are qualitatively changed, the motion activity of the powders is greatly increased, and the powders with the particle diameter of 10 microns or less are equivalent to 1600 meshes of powders, and can float in the air, because the individual bodies become much lighter after the powders have a small diameter, and have floating capacity which is not available originally, and in addition, the powders have adsorption and polymerization capacities, so that when the particle diameter of the powders is less than 1000 meshes of ultrafine powders, the difficulty of the mixing process is greatly increased, and the ultrafine powders are passivated, so that the fine powders become moderately coarse, an oxide film can be formed, the powders are prevented from spontaneous combustion, and the difficulty of the mixing process can be reduced, and the mixing efficiency is improved.
Furthermore, after all steps S1 to S4 are finished, the powder is directly conveyed to a heating furnace through a belt conveyor, so that a worker does not need to carry the powder after detecting the particle diameter, the loose specific gravity and the fluidity of the powder, and the working efficiency can be improved.
The working process comprises the following steps: firstly distinguishing powder to be mixed, grinding overweight powder, grinding and refining oversize powder, passivating the ultrafine powder if the ultrafine powder exists, adjusting the particle diameter, apparent specific gravity and fluidity of the powder to be mixed so as to improve the mixing quality and mixing efficiency of dry powder, then heating and annealing the powder, mixing the powder by using a double-motion mixer after improving the chemical purity of the powder so as to enable the powder to be mixed more efficiently and uniformly, then granulating by using spray drying, adding paraffin-alcohol into the powder, stirring the mixture into uniform slurry containing 75 to 80 percent of powder, and conveying the slurry into an atomizing tower by using nitrogen for spraying. The slurry is atomized into spherical slurry drops under the action of the surface tension of alcohol. They dried into fine spherical or pear-shaped pellets by the hot nitrogen encounter and collected at the bottom of the tower;
it is worth explaining that the spray drying granulation can ensure that the prepared powder particles are soft, uniform in particle size, high in sphericity, good in fluidity, short in drying granulation time, less in dirt, continuous in production and more in line with the flow of automatic production, the particle size, the apparent density and the dry and wet degree of the powder particles are easy to control, and the premixing process is more efficient;
and the pretreatment process that different kinds of powder need has been considered, carry out the pertinence to its characteristic and handle, it is more high-efficient to ensure follow-up mixed technology, it is better to mix the effect, the problem that follow-up transportation may produce has still been considered, the change of its internal chemical property is caused very easily to the suppression powder, and the segregation condition of whole powder weight down also can appear in transportation process, bring the difficulty for later stage process preparation, influence the product quality, so dry pelletization is carried out to it, can ensure that the mixing of powder is more even, promote the chemical purity of powder, can also ensure that follow-up transportation can not produce segregation phenomenon, kill many birds with one stone, whole process saves time, high efficiency, the powder granule that is suitable for mixes many kinds.
In the description of the present invention, it is to be understood that the terms "front-back", "left-right", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or component must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the invention.
Of course, in this disclosure, those skilled in the art should understand that the terms "a" and "an" should be interpreted as "at least one" or "one or more", i.e., in one embodiment, one element may be present in one number, while in another embodiment, the element may be present in multiple numbers, and the terms "a" and "an" should not be interpreted as limiting the number.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily made by those skilled in the art in light of the technical teaching of the present invention should be included within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. An efficient powder premixing process is characterized in that: comprises the steps of
S1: thickness discrimination, namely discriminating the thickness of each powder to be mixed, and crushing and grinding the coarsest powder in advance to enable the particle size to be close to the average value of the whole powder;
s2: distinguishing the weight, namely distinguishing the weight of each powder needing to be mixed, and grinding and refining the heaviest powder;
s3: drying and dehumidifying, namely drying and dehumidifying all the powder to be mixed;
s4: detecting the fluidity, namely detecting the fluidity of all the powder needing to be mixed by using a powder stacking angle;
s5: heating treatment, namely heating treatment is carried out on the raw material powder;
s6: annealing treatment, wherein the annealing temperature is controlled to be 50 to 60 percent of the absolute temperature of the melting point of the annealing treatment and is carried out in vacuum;
s7: mixing, namely mixing all the powder to be mixed, and adding a lubricant in the mixing process;
s8: spray drying and granulating, and making the mixed small granule powder into large granule powder or granule.
2. The process for efficient premixing of powder as claimed in claim 1, wherein the spray drying granulation of step S8 comprises
(1) Dripping paraffin alcohol liquid;
(2) Stirring until the powder content is 75-80% and uniform slurry is obtained;
(3) Conveying nitrogen;
(4) Spraying in an atomizing tower;
(5) Atomizing to form spherical paddle drops;
(6) Hot nitrogen treatment is carried out to form fine spherical or pear-shaped aggregates;
(7) And (4) collecting and conveying.
3. The process of claim 1, wherein the mixing step S7 is carried out by a double-motion mixer with a moderate speed of motion and a linear speed of blade tip lower than 200 m/min.
4. The process of claim 1, wherein the steps S1, S2 and S3 are performed simultaneously, and the powders to be mixed are placed in a container capable of being heated at an elevated temperature and physically ground until the particle size is relatively uniform by visual observation.
5. The process of claim 1, wherein the angle of the stacking angle in step S4 is less than 40 degrees, and when step S1, step S2 and step S3 are performed simultaneously, the stacking angle of the powder relative to the mixed powder is detected to determine whether dry powder with poor flowability exists, and if dry powder with poor flowability exists, the drying and dehumidifying time in step S3 is prolonged.
6. The efficient powder premixing process of claim 2, wherein a specific binder is added during the process of stirring the uniform slurry, and then the mixed powder can be compacted, packaged and conveyed by a powder blank pressing method during the process of collecting and conveying.
7. The process of claim 1, wherein the steps S5 and S6 are performed in a reducing atmosphere, the reducing atmosphere is a mixture of hydrogen and nitrogen, the step S5 heat treatment process is performed in a vacuum furnace, the temperature is controlled between 60 ℃ and 350 ℃ and the time is controlled between 0.5 hour and 3 hours, and the step S6 annealing treatment process is performed in a reduction annealing furnace, and the temperature is controlled between 500 ° and 1000 °.
8. The process for high-efficiency premixing of powder in claim 1, wherein the heavier and coarser powder is ground in step S1 and step S2 by wet grinding and adding industrial alcohol for grinding.
9. A process for efficient premixing of powders as defined in claim 1 wherein some ultra fine powders are pre-passivated in steps S1 and S2.
10. The process of claim 1, wherein after all steps S1 to S4 are completed, the powder is directly conveyed to the heat-treated furnace by a belt conveyor.
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Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1274531A (en) * | 1968-06-26 | 1972-05-17 | Smith Inland A O | Method of making alloy steel powder |
| US4397889A (en) * | 1982-04-05 | 1983-08-09 | Gte Products Corporation | Process for producing refractory powder |
| CN103589961A (en) * | 2013-12-06 | 2014-02-19 | 深圳市麦捷微电子科技股份有限公司 | Alloyed powder and manufacturing method and application thereof |
| CN106216699A (en) * | 2016-09-29 | 2016-12-14 | 柳州增程材料科技有限公司 | A kind of 3D prints and uses metal dust preparation technology |
| CN106346010A (en) * | 2016-09-29 | 2017-01-25 | 柳州增程材料科技有限公司 | Method for preparing additive manufacturing material |
| CN108393484A (en) * | 2018-02-06 | 2018-08-14 | 广东正德材料表面科技有限公司 | A kind of metal-ceramic nano composite construction feeding used for hot spraying and preparation method thereof |
| CN109894609A (en) * | 2019-03-19 | 2019-06-18 | 柳州增程材料科技有限公司 | A kind of production technology of increasing material manufacturing material |
| CN110273094A (en) * | 2019-08-05 | 2019-09-24 | 赣州锐科合金材料有限公司 | A kind of preparation method of cemented carbide powder |
| US20200230702A1 (en) * | 2017-02-17 | 2020-07-23 | Teknologian Tutkimuskeskus Vtt Oy | Method for producing hard metal powder, and hard metal powder |
| CN112530655A (en) * | 2020-11-25 | 2021-03-19 | 广东泛瑞新材料有限公司 | Low-power-consumption soft magnetic alloy material and preparation method and application thereof |
| CN114054761A (en) * | 2021-11-17 | 2022-02-18 | 株洲硬质合金集团有限公司 | Preparation method of metal ceramic powder for 3D printing |
| CN114799184A (en) * | 2022-05-12 | 2022-07-29 | 江西咏泰粉末冶金有限公司 | Preparation method of high-uniformity large-particle spherical composite powder |
-
2022
- 2022-08-29 CN CN202211050570.2A patent/CN115365491B/en active Active
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1274531A (en) * | 1968-06-26 | 1972-05-17 | Smith Inland A O | Method of making alloy steel powder |
| US4397889A (en) * | 1982-04-05 | 1983-08-09 | Gte Products Corporation | Process for producing refractory powder |
| CN103589961A (en) * | 2013-12-06 | 2014-02-19 | 深圳市麦捷微电子科技股份有限公司 | Alloyed powder and manufacturing method and application thereof |
| CN106216699A (en) * | 2016-09-29 | 2016-12-14 | 柳州增程材料科技有限公司 | A kind of 3D prints and uses metal dust preparation technology |
| CN106346010A (en) * | 2016-09-29 | 2017-01-25 | 柳州增程材料科技有限公司 | Method for preparing additive manufacturing material |
| US20200230702A1 (en) * | 2017-02-17 | 2020-07-23 | Teknologian Tutkimuskeskus Vtt Oy | Method for producing hard metal powder, and hard metal powder |
| CN108393484A (en) * | 2018-02-06 | 2018-08-14 | 广东正德材料表面科技有限公司 | A kind of metal-ceramic nano composite construction feeding used for hot spraying and preparation method thereof |
| CN109894609A (en) * | 2019-03-19 | 2019-06-18 | 柳州增程材料科技有限公司 | A kind of production technology of increasing material manufacturing material |
| CN110273094A (en) * | 2019-08-05 | 2019-09-24 | 赣州锐科合金材料有限公司 | A kind of preparation method of cemented carbide powder |
| CN112530655A (en) * | 2020-11-25 | 2021-03-19 | 广东泛瑞新材料有限公司 | Low-power-consumption soft magnetic alloy material and preparation method and application thereof |
| CN114054761A (en) * | 2021-11-17 | 2022-02-18 | 株洲硬质合金集团有限公司 | Preparation method of metal ceramic powder for 3D printing |
| CN114799184A (en) * | 2022-05-12 | 2022-07-29 | 江西咏泰粉末冶金有限公司 | Preparation method of high-uniformity large-particle spherical composite powder |
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