Method of obtaining metal powder (versions)

FIELD: technological processes.

SUBSTANCE: invention pertains to plasma technology, and specifically to methods of obtaining metal powder. The method involves igniting a discharge between two electrodes, one of which is an anode, made from the spray material, with diameter of 10-40 mm. The cathode is in form of an electrolyte. The process is carried out under the following parameters: voltage between electrodes - 800 - 1600 V, discharge current - 750-1500 mA, distance between the anode and the electrolyte - 2-10 mm. According to the alternative method, the spray material is the anode, and the cathode is the electrolyte. The process takes place under the following parameters: voltage between electrodes - 500-650 V, discharge current - 1.5-3 A, distance between the cathode and electrolyte - 2-10 mm. The technical outcome is the increased efficiency of obtaining metal powder.

EFFECT: increased efficiency of obtaining metal powder.

2 cl, 8 dwg

 

The invention relates to a plasma engineering and technology and can be used to improve the performance of producing metal powder.

Known methods and devices of producing metal powder by electrolysis from a solution have significant disadvantages: are complex and have low productivity. For example, in the method and device of the authors of Woloshuk Y.M. and S. Black. / A.S. USSR №1177397, bull. No. 033. 07.09.89, the apparatus for producing metal powder/, working electrodes pre-trained for 3-5 h in terms of two-ply bath with polarized alternating current power 0,1-0,12 And, in addition, the electrodes rotate with an angular speed of 2 rpm In the process of electrolysis from the surface of working electrodes continuously removing the products of electrolysis using permanent magnets embedded in the polyethylene. The device contains three working and auxiliary electrodes, which are connected to an AC power source. The performance of the device 0.001 kg/hour.

As a prototype of the selected method of producing metal powder in which the powder is produced by ignition of the discharge between the two electrodes. "Powders of non-ferrous metals". Reference ed. Ed. Sea. - M.: metallurgy, 1997, s-182.

However, the prototype has significant disadvantages: note the imposition of expensive equipment (vacuum chamber system with regeneration of the electrolyte and the movement of the solid electrode), and the prototype has insufficient capacity of producing metal powder.

Solved the technical problem is to increase the productivity of producing metal powder.

Solved the technical problem, in the first embodiment, in the method of producing metal powder, including the ignition of the discharge between the two electrodes is achieved by the fact that one of the electrodes - the anode, made of a sprayable material, with a diameter of 10-40 mm, and as the other electrode, the cathode, use the electrolyte, and the process is conducted with the following parameters: voltage between the electrodes is 800-1600 V, the discharge current 750-1500 mA, the distance between the anode and electrolyte - 2-10 mm

Solved the technical problem, according to the second variant, the method of producing metal powder, including the ignition of the discharge between the two electrodes is achieved by the fact that one of the electrodes is a cathode made of a sprayable material, with a diameter of 10-40 mm, and as the other electrode, the anode, use the electrolyte, and the process is conducted with the following parameters: voltage between the electrodes 500-650, the discharge current of 1.5 a And 3 a, the distance between the cathode and the electrolyte 2-10 mm

Figure 1 shows a device for implementing the method of producing metal powder, the electric power experimental ustanovki first option.

Figure 2 shows the device for implementing the method of producing metal powder, the electric power of the experimental setup for the second option.

Figure 3 shows the device for implementing the method of producing metal powder by the first option.

4 shows a device for implementing the method of producing metal powder according to the second option.

Figure 5 shows the current-voltage discharge between the flow-through electrolytic anode of technical water and uncooled steel cathode and lMr=5 mm for the second option.

Figure 6 shows the dependence of the performance of oxide of iron powder on the discharge current for different diameters of the metal cathode (steel 45) 12 - dk=15 mm; 13 - dk=30 mm for the second option.

Figure 7 presents the characteristics of the magnetization ferrite powder 14 - ferrite brand MN; 15 - ferrite brand MMM; 16 - ferrite; 17 - Nono-ferrite iron; 18 - batch brand S; 19 - metal powder; 20 - metal powder after the heat treatment according to the second option.

On Fig shows a photograph of the metal powder in the first and second options.

Functional diagram of the experimental setup and device for implementing the method of producing metal powder in the first embodiment (Fig 1 and Fig.) contains the voltage regulator 1, which allows you to adjust the three-phase voltage from 0 to 660 In increasing three-phase transformer 2, the rectifier scheme Larionov 3, LC filter 4, the ballast resistor 5, the ammeter 6, voltmeter 7, the electrolytic bath 8, the copper plate 9 and sprayed anode 10.

Functional diagram of the experimental setup and device for implementing the method of producing metal powder according to the second variant (figure 2 and figure 4) contains the voltage regulator 1, which allows you to adjust the three-phase voltage from 0 to 660 In increasing three-phase transformer 2, the rectifier scheme Larionov 3, LC filter 4, the ballast resistor 5, the ammeter 6, voltmeter 7, the electrolytic bath 8, the copper plate 9 and a sputtered cathode 10.

The method of obtaining the oxide powder in the first embodiment (Fig 1 and Fig 3) is as follows: at atmospheric pressure of the sprayed material 10 is not cooled Steel (45) is placed over the surface of the electrolyte 11, the sprayed material serves a positive potential and the electrolyte (water) - negative potential, ignite the discharge, set the voltage between the electrodes 800≤U≤1600 V, the discharge current of 750 mA≤I≤1.5 a, the diameter of the anode 10≤da≤40 mm, interelectrode distance of 2≤l≤10 mm, where U is the voltage between the electrodes, I is the current bit is Yes, da- diameter solid cathode, l is the distance between the processed product and the electrolyte, the process is carried out for a time, until completely out of the sprayed material.

The method of obtaining the oxide powder according to the second variant (figure 2 and figure 4) as follows: sprayable material 10 is placed over the surface of the electrolyte 11, the sprayed material serves a negative potential, and the electrolyte is a positive potential, ignite the discharge, set the voltage between the electrodes 500≤U≤650 V, the discharge current of 1.5 mA≤I≤3 A, the diameter of the cathode 10≤da≤40 mm, interelectrode distance of 2≤l≤10 mm, where U is the voltage between the electrodes, I is the discharge current, da- diameter solid cathode, l is the distance between the processed product and the electrolyte.

Selecting ranges in the first embodiment is explained as follows. At low discharge currents I<750 mA stops spraying, when the discharge current higher than 1.5 And is drip breakdown of the material. The diameter of the metal anode was varied from 10 to 40 mm depending on the diameter of the metal anode establish the interelectrode distance in the range of 2 to 10 mm. Marginal optimal and maximum values of the diameter and the values of interelectrode distance is determined by the performance gain powder and d is sparsest powder. Within these limits the maximum performance (p=0.14 kg/hour). The main mass of the obtained powder (about 75%) is the dispersion of 0.025÷0,03 mm

The obtained oxide iron powder showed that 90% of the powder is magnetite Fe3O4, with the remainder consisting of iron oxide FeO. Magnetite Fe3O4included in the group of ferrites with spinel structure and is of practical interest for powder metallurgy magnetic materials. Of particular interest is the spherical shape of the particles magmatichnogo powder, which is the main condition of the isotropy of its magnetic properties. The study of the obtained powder in comparison with the reference ferrites shows considerably higher magnetic properties (Fig.7). The possibility of obtaining large values of the magnetic induction in the powder, in combination with the spherical shape of its particles, talks about the prospects of powders for use in the engineering industry.

Compared with the prototype method for producing metal powder by the first and second options allows to increase the productivity gain powder 7 times. This proves Fig.6, Fig.7 and Fig. Using this method it is possible to produce powders of various metals and alloys (3, 20, 45, W, WA, 10, tungsten, molybdenum and so on).

. Method of producing metal powder, comprising the ignition discharge between two electrodes, wherein one of the electrodes is an anode made of a sprayable material with a diameter of 10-40 mm, and as the other electrode, the cathode used in the electrolyte, and the process is carried out at a voltage between the electrodes 800-1600 V, the discharge current is 750-1500 mA, the distance between the anode and electrolyte - 2-10 mm

2. Method of producing metal powder, comprising the ignition discharge between two electrodes, wherein one of the electrodes is a cathode made of a sprayable material with a diameter of 10-40 mm, and as the other electrode, the anode used in the electrolyte, and the process is carried out at a voltage between the electrodes 500-650, the discharge current is 1.5-3 a distance between the cathode and the electrolyte - 2-10 mm



 

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7 cl, 5 dwg, 1 tbl

FIELD: metallurgy.

SUBSTANCE: invention relates to powder metallurgy, in particular, to production of powder materials with particle sizes below 0.2 mcm used in manufacturing cermet and composite materials, as well as those intended for use as fuel for thermite and pyro compositions. An aluminum wire is exploded in a gaseous chemically inert atmosphere. The aluminum powder thus produced is wetted with a solution of boric acid in ethanol with a 0,5 mole/l concentration, the powder being separated from solution in no less than an hour after wetting.

EFFECT: increase in thermal stability of aluminum powder to 580 °C.

2 tbl, 1 ex

FIELD: technological processes.

SUBSTANCE: invention pertains to plasma technology, and specifically to methods of obtaining metal powder. The method involves igniting a discharge between two electrodes, one of which is an anode, made from the spray material, with diameter of 10-40 mm. The cathode is in form of an electrolyte. The process is carried out under the following parameters: voltage between electrodes - 800 - 1600 V, discharge current - 750-1500 mA, distance between the anode and the electrolyte - 2-10 mm. According to the alternative method, the spray material is the anode, and the cathode is the electrolyte. The process takes place under the following parameters: voltage between electrodes - 500-650 V, discharge current - 1.5-3 A, distance between the cathode and electrolyte - 2-10 mm. The technical outcome is the increased efficiency of obtaining metal powder.

EFFECT: increased efficiency of obtaining metal powder.

2 cl, 8 dwg

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