CN113231642A - Preparation method of superfine copper-iron alloy powder - Google Patents
Preparation method of superfine copper-iron alloy powder Download PDFInfo
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- CN113231642A CN113231642A CN202110482297.XA CN202110482297A CN113231642A CN 113231642 A CN113231642 A CN 113231642A CN 202110482297 A CN202110482297 A CN 202110482297A CN 113231642 A CN113231642 A CN 113231642A
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/24—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from liquid metal compounds, e.g. solutions
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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
- B22F1/145—Chemical treatment, e.g. passivation or decarburisation
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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
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
- B22F9/22—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds using gaseous reductors
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Abstract
The invention aims to provide a preparation method of superfine copper-iron alloy powder with higher purity. The preparation method of the superfine copper-iron alloy powder provided by the invention comprises the following steps: (1) preparing a displacing agent aqueous solution; preparing a mixed aqueous solution of ferrous sulfate and copper sulfate; (2) adding the displacer aqueous solution and the mixed aqueous solution into a displacement reaction kettle for displacement reaction; (3) ultrasonic cleaning; (4) drying and roasting the solid precipitate to obtain copper oxide iron alloy powder; (5) and putting the copper oxide iron alloy powder into a reduction furnace for hydrogen reduction.
Description
Technical Field
The invention belongs to the technical field of metal powder preparation, and particularly relates to a preparation method of superfine copper-iron alloy powder.
Background
The powder metallurgy product is prepared by using metal powder or a mixture of metal and nonmetal powder as a raw material, generally through press forming, sintering and subsequent treatment, and has the advantages of little or no cutting processing, good surface smoothness, material saving, energy saving, suitability for mass production and the like. The trend in powder metallurgy development is toward a low-cost powder metallurgy production process with high dimensional stability and without shaping and heat treatment, such as sinter hardening, which is becoming a process for producing low-cost, high-performance powder metallurgy iron-based structural parts, and the overall manufacturing cost is reduced by about 30% compared to sintered low-alloy steels requiring heat treatment because shaping and heat treatment are not performed after sintering.
The traditional iron-copper powder preparation method mainly comprises the following steps: (1) mechanical mixing method, namely directly mechanically mixing iron powder and copper powder; (2) the copper-clad iron method, namely cladding the iron powder by copper by using a chemical plating method; (3) the atomization method is that firstly, iron-copper metal is melted and then atomized into iron-copper powder.
The iron and copper powder prepared by the different production processes has greatly different properties and has advantages and disadvantages. In summary, the iron-copper powder produced by the mechanical mixing method has good formability, but is easy to segregate during transportation, forming and the like, the shrinkage rate is not easy to control, and the problem is more obvious particularly when the iron-copper powder is prepared into superfine powder. The copper-clad iron process is used as a traditional production process, adopts chemical cladding production, has great pollution to the environment, is difficult to control the copper content, and particularly can not effectively control harmful elements in the reaction process. The alloy powder produced by the water atomization method has high purity, uniform tissue and good process performance, and the crystal structure is refined due to the rapid solidification effect, so that the macrosegregation of a second phase is eliminated, but in the actual production process, the product hardness is higher due to the high water cooling speed, meanwhile, the iron-copper powder produced by the water atomization has higher apparent density, the cold press molding performance is poorer, and particularly in the production of oil-containing bearings and diamond tools, the problems of insufficient green body strength, easy green body cracking and the like are generally caused.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a preparation method of superfine copper-iron alloy powder with higher purity.
In order to solve the technical problem, the invention provides a preparation method of superfine copper-iron alloy powder, which is characterized by comprising the following steps:
(1) preparing a displacing agent aqueous solution; preparing a mixed aqueous solution of ferrous sulfate and copper sulfate;
(2) adding the displacer aqueous solution and the mixed aqueous solution into a displacement reaction kettle for displacement reaction;
(3) carrying out solid-liquid separation after ultrasonic cleaning;
(4) drying and roasting the solid precipitate to obtain copper oxide iron alloy powder;
(5) and putting the copper oxide iron alloy powder into a reduction furnace for hydrogen reduction.
Preferably, in the step (1), the mass ratio of the ferrous sulfate to the copper sulfate is as follows: 1:(0.2-0.8).
Preferably, in the step (1), the mass ratio of the ferrous sulfate to the copper sulfate is as follows: 1:(0.35-0.5).
Preferably, after the copper sulfate and the ferric sulfate are mixed and proportioned, the concentration of the ferric sulfate is 0.7-1.2mol/L, and the concentration of the copper sulfate is 0.3-0.7 mol/L.
Preferably, in the displacement reaction in the step (2), firstly adding one of the displacing agent aqueous solution or the mixed aqueous solution into the displacement reaction kettle, starting stirring, wherein the stirring speed is 200-.
Preferably, in the step (2), after the feed liquid is added, the mixture is aged for 30 to 60 minutes and is kept stand for 30 to 60 minutes.
Preferably, the ultrasonic cleaning further comprises a step of centrifuging to separate out a solid precipitate.
Preferably, in the step (4), the roasting temperature is 300-500 ℃, the roasting time is 0.3-2.5 hours, and oxygen is introduced into the roasting furnace during roasting.
Preferably, in the step (5), the reduction temperature is 300-500 ℃, the hydrogen flux is 0.2-6L/min, and the reduction time is 0.5-3 hours.
Preferably, the substitution agent is one of sodium carbonate or ammonium bicarbonate, and the proportioning mass of the sodium carbonate or ammonium bicarbonate and water in the substitution agent aqueous solution is 1 (5-8).
The preparation method of the superfine copper-iron alloy powder provided by the invention can be used for preparing the superfine copper-iron alloy powder with higher purity.
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The foregoing and other objects, features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings. Like reference numerals refer to like parts throughout the drawings, and the drawings are not intended to be drawn to scale in actual dimensions, emphasis instead being placed upon illustrating the principles of the invention.
FIG. 1 is a schematic flow chart of a method for preparing an ultrafine Cu-Fe alloy powder according to example 1 of the present invention;
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
The embodiment of the invention provides a preparation method of superfine copper-iron alloy powder, which comprises the following steps:
(1) preparing a displacing agent aqueous solution; preparing a mixed aqueous solution of ferrous sulfate and copper sulfate;
(2) adding the displacer aqueous solution and the mixed aqueous solution into a displacement reaction kettle for displacement reaction;
(3) ultrasonic cleaning;
(4) drying and roasting the solid precipitate to obtain copper oxide iron alloy powder;
(5) and putting the copper oxide iron alloy powder into a reduction furnace for hydrogen reduction.
The preparation method of the superfine copper-iron alloy powder provided by the embodiment of the invention adopts coprecipitation hydrometallurgy to prepare the superfine copper-iron alloy powder, the average grain diameter is 5-40 mu m, and the purity reaches 99.9%.
According to the preparation method of the superfine copper-iron alloy powder provided by the embodiment of the invention, the cost proportion of the alloy powder can be accurately controlled by controlling the proportion of the mixed aqueous solution, the nucleation speed and the nucleation mode of the powder in the aqueous solution can be accurately controlled by the process conditions such as the feeding mode, the stirring speed, the temperature and the like of the mixed aqueous solution and the replacement solution, the preparation of the alloy powder with narrow particle size range and small particle size is realized, and the preparation process accords with the nucleation rule and related thermodynamics and kinetics of the powder in the aqueous solution.
The superfine copper-iron alloy powder prepared by the preparation method provided by the embodiment of the invention has the advantages of much smaller granularity than that of the powder prepared by the existing atomization method and electrolysis method, low production cost and simple process flow. The grain size of the prepared powder can reach the nanometer level.
In a preferred embodiment, in the step (1), the mass ratio of the ferrous sulfate to the copper sulfate is as follows: 1:(0.2-0.8).
In a preferred embodiment, in the step (1), the mass ratio of the ferrous sulfate to the copper sulfate is as follows: 1:(0.35-0.5). The composition ratio of the final alloy powder can be accurately controlled.
In a preferred embodiment, after the copper sulfate and the ferric sulfate are mixed and proportioned, the concentration of the ferric sulfate is 0.7-1.2mol/L, and the concentration of the copper sulfate is 0.3-0.7 mol/L.
In a preferred embodiment, in the step (2), the substitution reaction is performed by firstly adding one of the aqueous solution of the substitution agent or the mixed aqueous solution into the substitution reaction kettle, starting stirring, wherein the stirring speed is 200 and 500R/MIN, raising the temperature to 40-60 ℃, and then adding the other one of the aqueous solution of the substitution agent or the mixed aqueous solution, wherein the adding speed is 20-80L/MIN.
The method specifically comprises the following steps: adding the aqueous solution of the displacing agent into the displacement reaction kettle, starting stirring at the stirring speed of 200-. Raising the temperature to 40-60 ℃, and then adding a mixed solution of ferrous sulfate and copper sulfate, wherein the adding speed of the mixed solution is 20-80L/MIN; or adding the mixed solution of ferrous sulfate and copper sulfate into the replacement reaction kettle, starting stirring at the stirring speed of 200-500R/min. Raising the temperature to 40-60 ℃, and then adding the aqueous solution of the displacing agent at the speed of 20-80L/MIN.
In a preferred embodiment, in the step (2), after the feed liquid is added, the mixture is aged for 30 to 60 minutes and is kept stand for 30 to 60 minutes.
In a preferred embodiment, the ultrasonic cleaning further comprises a step of centrifuging to separate a solid precipitate.
In a preferred embodiment, in the step (4), the roasting temperature is 300-500 ℃, the roasting time is 0.3-2.5 hours, and oxygen is introduced into the roasting furnace during roasting.
In a preferred embodiment, in the step (5), the reduction temperature is 300-500 ℃, the hydrogen flux is 0.2-6L/min, and the reduction time is 0.5-3 hours.
In a preferred embodiment, the substitution agent is one of sodium carbonate or ammonium bicarbonate, and the proportioning mass of the sodium carbonate or ammonium bicarbonate and water in the substitution agent aqueous solution is 1 (5-8). Different particle sizes can be prepared by adopting different concentrations and proportions.
In order that the technical solutions of the present invention may be further understood and appreciated, several preferred embodiments are now described in detail.
Example 1
Referring to the preparation process of fig. 1, iron sulfate: the mass ratio of the copper sulfate is 1 (0.35-0.52), after the copper sulfate and the ferric sulfate are mixed and proportioned, the concentration of the ferric sulfate is 0.7-1.2mol/L, and the concentration of the copper sulfate is 0.3-0.7 mol/L.
The substitution agent is sodium carbonate, the mass ratio of the sodium carbonate to water is 1:64,
firstly adding a sodium carbonate solution into the replacement reaction kettle, starting stirring at the stirring speed of 200-. The temperature is raised to 40-60 ℃. Then adding mixed solution of ferrous sulfate and copper sulfate at a rate of 20-80L/MIN.
After the feed liquid is added, the mixture is aged for 30-60 minutes, kept stand for 30-60 minutes, centrifugally separated to obtain solid precipitate, and ultrasonically cleaned.
The solid precipitate is dried and roasted, the roasting temperature is 300-500 ℃, and the roasting time is 0.3-2.5 hours. And introducing oxygen into the roasting furnace to obtain the copper oxide iron alloy powder.
The copper oxide iron alloy powder is put into a reduction furnace for hydrogen reduction, the reduction temperature is 300-500 ℃, the hydrogen flux is 0.2-6L/min, and the reduction time is 0.5-3 hours.
The obtained copper-iron alloy powder has copper content of 10-25% and iron residue, average particle size of 25-30 μm, purity of 99.9%, and specific gravity of 1.2-1.5g/CM 3.
Example 2
Ferrous sulfate: the mass ratio of the copper sulfate is 1 (0.35-0.52), after the copper sulfate and the ferric sulfate are mixed and proportioned, the concentration of the ferric sulfate is 0.7-1.2mol/L, and the concentration of the copper sulfate is 0.3-0.7 mol/L.
The substitution agent is sodium carbonate, the mass ratio of the sodium carbonate to water is 1:64,
firstly adding the mixed solution of ferrous sulfate and copper sulfate into the replacement reaction kettle, starting stirring at the stirring speed of 200-500R/min. Raising the temperature to 40-60 ℃, and then adding the ammonium bicarbonate solution at the speed of 20-80L/MIN.
After the feed liquid is added, the mixture is aged for 30-60 minutes, kept stand for 30-60 minutes, centrifugally separated to obtain solid precipitate, and ultrasonically cleaned.
Drying and roasting the solid precipitate at 300-500 deg.c for 0.3-2.5 hr, and introducing oxygen to the roasting furnace to obtain copper oxide-iron alloy powder.
The copper oxide iron alloy powder is put into a reduction furnace for hydrogen reduction, the reduction temperature is 300-500 ℃, the hydrogen flux is 0.2-6L/min, and the reduction time is 0.5-3 hours.
The obtained copper-iron alloy powder has copper content of 10-25% and iron residue, average particle size of 10-15 μm, purity of 99.9%, and specific gravity of 1.0-1.2g/CM 3.
The above-mentioned embodiments only express some embodiments of the invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of intellectual property rights of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the scope of intellectual property rights of the present invention shall be subject to the appended claims.
Claims (10)
1. The preparation method of the superfine copper-iron alloy powder is characterized by comprising the following steps:
(1) preparing a displacing agent aqueous solution; preparing a mixed aqueous solution of ferrous sulfate and copper sulfate;
(2) adding the displacer aqueous solution and the mixed aqueous solution into a displacement reaction kettle for displacement reaction;
(3) carrying out solid-liquid separation after ultrasonic cleaning;
(4) drying and roasting the solid precipitate to obtain copper oxide iron alloy powder;
(5) and putting the copper oxide iron alloy powder into a reduction furnace for hydrogen reduction.
2. The method for preparing an ultrafine copper-iron alloy powder according to claim 1, wherein in the step (1), the mass ratio of the ferrous sulfate to the copper sulfate is: 1:(0.2-0.8).
3. The method for preparing an ultrafine copper-iron alloy powder according to claim 2, wherein in the step (1), the mass ratio of the ferrous sulfate to the copper sulfate is: 1:(0.35-0.5).
4. The method of claim 1, wherein the mixture of copper sulfate and iron sulfate has an iron sulfate concentration of 0.7-1.2mol/L and a copper sulfate concentration of 0.3-0.7 mol/L.
5. The method for preparing ultra-fine Cu-Fe alloy powder as claimed in claim 1, wherein in the displacement reaction of step (2), one of the displacer aqueous solution or the mixed aqueous solution is added to the displacement reaction vessel, stirring is started, the stirring speed is 200-500R/MIN, the temperature is raised to 40-60 ℃, and then the other of the displacer aqueous solution or the mixed aqueous solution is added at the speed of 20-80L/MIN.
6. The method for preparing an ultrafine copper-iron alloy powder according to claim 1, wherein in the step (2), after the completion of the addition of the feed liquid, the mixture is aged for 30 to 60 minutes and left to stand for 30 to 60 minutes.
7. The method of preparing an ultrafine copper-iron alloy powder according to claim 1, further comprising a step of centrifuging a solid precipitate before the ultrasonic cleaning.
8. The method for preparing ultra-fine Cu-Fe alloy powder according to claim 1, wherein in the step (4), the calcination temperature is 300 ℃ to 500 ℃, the calcination time is 0.3 to 2.5 hours, and oxygen is introduced into the calcination furnace during calcination.
9. The method for preparing an ultra-fine copper-iron alloy powder according to claim 1, wherein in the step (5), the reduction temperature is 300 ℃ to 500 ℃, the hydrogen flux is 0.2 to 6L/min, and the reduction time is 0.5 to 3 hours.
10. The method for preparing the ultrafine copper-iron alloy powder according to claim 1, wherein the substitution agent is one of sodium carbonate and ammonium bicarbonate, and the ratio of the sodium carbonate or the ammonium bicarbonate to water in the substitution agent aqueous solution is 1 (5-8).
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1830606A (en) * | 2006-04-14 | 2006-09-13 | 北京科技大学 | Method of preparing ultrafine alloy powder by coprecipitation coreduction |
| JP2010242179A (en) * | 2009-04-07 | 2010-10-28 | Noritake Co Ltd | Alloy fine particle, method for production thereof and use thereof |
| CN104120351A (en) * | 2014-07-21 | 2014-10-29 | 东北大学 | Method for directly smelting copper-bearing antibacterial stainless steel by utilizing copper slag for reducing molten iron |
| CN105458283A (en) * | 2015-11-24 | 2016-04-06 | 太原理工大学 | Method for green synthesis of nanometer zero-valent iron-copper bi-metal material and application |
| CN111485101A (en) * | 2020-03-19 | 2020-08-04 | 广东华诺勤耕材料科技有限公司 | Method for recovering iron from iron-containing ore |
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- 2021-04-30 CN CN202110482297.XA patent/CN113231642A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1830606A (en) * | 2006-04-14 | 2006-09-13 | 北京科技大学 | Method of preparing ultrafine alloy powder by coprecipitation coreduction |
| JP2010242179A (en) * | 2009-04-07 | 2010-10-28 | Noritake Co Ltd | Alloy fine particle, method for production thereof and use thereof |
| CN104120351A (en) * | 2014-07-21 | 2014-10-29 | 东北大学 | Method for directly smelting copper-bearing antibacterial stainless steel by utilizing copper slag for reducing molten iron |
| CN105458283A (en) * | 2015-11-24 | 2016-04-06 | 太原理工大学 | Method for green synthesis of nanometer zero-valent iron-copper bi-metal material and application |
| CN111485101A (en) * | 2020-03-19 | 2020-08-04 | 广东华诺勤耕材料科技有限公司 | Method for recovering iron from iron-containing ore |
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Application publication date: 20210810 |