CN113857272A - Thermal drawing device and drawing method of ultrafine filament - Google Patents
Thermal drawing device and drawing method of ultrafine filament Download PDFInfo
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- CN113857272A CN113857272A CN202111050219.9A CN202111050219A CN113857272A CN 113857272 A CN113857272 A CN 113857272A CN 202111050219 A CN202111050219 A CN 202111050219A CN 113857272 A CN113857272 A CN 113857272A
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- wire
- drawing device
- metal wire
- heating
- heating chamber
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES, PROFILES OR LIKE SEMI-MANUFACTURED PRODUCTS OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C1/00—Manufacture of metal sheets, wire, rods, tubes or like semi-manufactured products by drawing
- B21C1/02—Drawing metal wire or like flexible metallic material by drawing machines or apparatus in which the drawing action is effected by drums
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES, PROFILES OR LIKE SEMI-MANUFACTURED PRODUCTS OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
- B21C9/00—Cooling, heating or lubricating drawing material
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- Metal Extraction Processes (AREA)
- Extrusion Of Metal (AREA)
Abstract
The invention discloses a hot drawing device and a drawing method of superfine filaments, wherein the hot drawing device comprises an induction heating coil and a heating chamber with a heating cavity, and a drawing die and a plurality of SiO (silicon dioxide) films are arranged in the heating cavity2a/Fe shell-core pellet, wherein the induction heating coil is capable of making SiO by generating an alternating magnetic field2The Fe shell-core spherical particles generate heat, so that the metal wire in the heating cavity is heated, and the drawing die can process the heated metal wire.
Description
Technical Field
The invention relates to the field of metal wire materials, in particular to a hot drawing device and a drawing method of ultra-fine wires.
Background
Alloy wire produced by using the metal difficult to deform has good comprehensive performance and is an important material for aviation, aerospace, shipbuilding and chemical industry. In addition, the metal wire material difficult to deform can be widely used in the field of weaving, such as biomedical materials, metal knitted clothes, precise printing screens and the like. However, the metal which is difficult to deform usually has a hexagonal close-packed structure, and plastic forming at room temperature is difficult. At present, the heating mode of the traditional hot extrusion method is usually gas or electric heating, and the traditional hot extrusion method is used for drawing and producing the wire material of the metal difficult to deform, and the wire material has shorter length and is difficult to produce the wire material with the micro diameter.
Therefore, it is necessary to provide an apparatus and a method for drawing ultrafine wires to solve the above problems.
The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.
Disclosure of Invention
The invention aims to provide a hot drawing device and a drawing method of an ultra-fine wire, which can carry out hot drawing processing on a metal difficult to deform into a wire material with a fine diameter.
In order to achieve the above objects, an embodiment of the present invention provides a hot drawing apparatus for ultra-fine wires, including an induction heating coil and a heating chamber having a heating cavity, wherein a drawing die and a plurality of SiO are disposed in the heating cavity2Fe shell-core spherulites.
Wherein the induction heating coil is capable of making SiO by generating an alternating magnetic field2the/Fe shell-core spherulites generate heat, so that the metal wire in the heating cavity is heated, and the drawing die can process the heated metal wire.
In one or more embodiments of the present invention, the hot drawing apparatus further includes a feeding wire winder on which the metal wire is wound, the metal wire being fed from the feeding wire winder into the heating chamber of the heater.
In one or more embodiments of the invention, the heating chamber is made of quartz material.
In one or more embodiments of the present invention, the heat drawing device further includes a temperature controller connected to the induction heating coil for controlling an output power of the induction heating coil to control a temperature in the heating chamber.
In one or more embodiments of the present invention, a thermocouple is further connected to the temperature controller, and the thermocouple is at least partially located in the heating chamber to detect the temperature in the heating chamber and feed back a temperature signal to the temperature controller.
In one or more embodiments of the invention, a driving wire collecting machine is further arranged outside the heating chamber, and is used for driving the metal wire to pass through the drawing die to complete the wire drawing process, and collecting the drawn metal wire.
In one or more embodiments of the present invention, the drawing rate of the hot drawing device is 10 to 300 m/min.
In one or more embodiments of the present invention, the drawing wire diameter of the hot drawing device is 5 to 20 μm.
In one or more embodiments of the invention, the SiO2The grain size of the Fe shell-core spherulites is 3-10 mu m.
The invention also discloses a drawing method of the ultramicro filament, which comprises the following steps: placing the metal wire to be drawn in a state of being filled with SiO2Heating cavity of heater for Fe shell-core pellet; starting the induction heating coil to make SiO2The Fe shell-core spherical particle generates heat to heat the metal wire to be drawn; and then starting the driving wire collecting machine to drive one end of the metal wire to be drawn to pass through the drawing die, so as to finish the drawing process of the metal wire.
Compared with the prior art, according to the hot drawing device and the drawing method of the ultrafine wire provided by the embodiment of the invention, the SiO in the heating cavity is enabled to be heated through the alternating magnetic field generated by the induction heating coil2The Fe shell-core spherulite cuts alternating magnetic lines of force to generate eddy current to improve atomic activity, and generates heat energy by utilizing collision friction of high-speed moving atoms, so that the process of heating the metal wire to be drawn is realized, and then the metal wire to be drawn is processed into a metal wire with a micro diameter after passing through a drawing die. The hot drawing device of the ultra-fine wire of the invention is provided with a heating deviceLow energy consumption in the thermal process, high temperature control precision and excellent surface quality of the produced ultramicro diameter metal wire.
Drawings
FIG. 1 is a schematic view of a hot drawing apparatus for ultra-fine wires according to an embodiment of the present invention.
Description of the main reference numerals:
1. a heating chamber; 2. SiO22Fe shell-core spherulites; 3. an induction heating coil; 4. a heating cavity; 5. drawing the die; 6. a metal wire; 7. feeding a wire winding machine; 8. driving a filament collecting machine; 9. a temperature controller; 10. a thermocouple; 11. a power source.
Detailed Description
The following detailed description of the present invention is provided in conjunction with the accompanying drawings, but it should be understood that the scope of the present invention is not limited to the specific embodiments.
Throughout the specification and claims, unless explicitly stated otherwise, the word "comprise", or variations such as "comprises" or "comprising", will be understood to imply the inclusion of a stated element or component but not the exclusion of any other element or component.
As shown in FIG. 1, the apparatus for drawing an ultrafine wire according to a preferred embodiment of the present invention includes an induction heating coil 3, a heating chamber 1, and an SiO2/Fe shell-core pellet 2.
In one embodiment, the heating chamber 1 is provided with a heating chamber 4, the heating chamber 4 is provided with a drawing die 5, wherein the metal wire 6 to be drawn is heated and then processed into the metal wire 6 in ultra-fine filament shape through the drawing die 5, namely the final product. The remaining space in the heating chamber 4, in addition to the drawing die 5, is filled with a plurality of SiO2/Fe shell-core pellets 2. The induction heating coil 3 (the dotted frame part in fig. 1 is the induction heating coil 3) can generate an alternating magnetic field, so that the SiO2/Fe shell-core pellets 2 in the heating chamber 4 cut alternating magnetic lines to generate eddy currents to improve atomic activity, and the collision friction of high-speed moving atoms is utilized to generate heat energy, thereby realizing the process of heating the metal wire material 6 to be drawn.
In the above embodiment, the SiO2/Fe core-shell pellets 2 are selected to heat the metal wire 6 to be drawn because uniform heating of the metal wire 6 can be achieved, thereby avoiding poor surface quality of drawn ultra-fine wires caused by uneven heat when the metal wire 6 is drawn into fine wires through the drawing die 5 in the later stage.
In one embodiment, the SiO2/Fe shell-core pellet 2 is made as follows:
firstly, melting iron into a molten state, blowing and atomizing the molten iron into spherical particles through high-pressure argon by using an atomizer in the atmosphere of an atomizing medium of the high-pressure argon, and separating the spherical iron powder from a mixed gas of the argon and the spherical iron powder in a cyclone separator and collecting the spherical iron powder for subsequent operation. Argon gas with the purity of 99.9-99.999% is adopted, and the furnace temperature is 1570-1600 ℃; and (3) spraying argon at 4-10 bar, and performing cyclone separation and screening after spray granulation to obtain the spherical iron powder with the average particle size of 1-5 microns.
And then, dipping the collected spherical iron powder into silica sol, wherein the concentration of the silica sol is controlled to be 15-35%, and the pH value is controlled to be 7.2-9. After a period of immersion, the solution is filtered to collect the core-shell pellets and placed in a drying oven to be dried at a temperature of 80 ℃ to 120 ℃. And after drying, ball milling the shell and core particles for 5-10 h to crush and refine the shell and core particles, and finally screening, wherein the final particle size is controlled to be 3-10 mu m, and the rotation speed of the screening machine is 200-800 r.p.m.
In the above embodiment, the SiO2 is used to wrap the iron powder, so that the adhesion of the spherical Fe powder to each other at high temperature can be avoided, and the oxidation of the Fe powder can be avoided. The heating temperature of the SiO2/Fe shell-core pellet 2 can be controlled between 25 ℃ and 700 ℃.
Wherein the SiO2/Fe shell-core spherulites 2 with the grain diameter of 3-10 μm have good fluidity; and the porosity between a large amount of SiO2/Fe shell and core pellets 2 after being stacked is low, so that the SiO2/Fe shell and core pellets 2 can be fully contacted with the wire; thereby reducing the contact area of the metal wire 6 and oxygen or air in the process of heating the metal wire 6 drawn by the belt, and having the functions of preventing oxidation and high heating efficiency.
In one embodiment, the hot drawing apparatus further comprises a feeding wire winder 7, the feeding wire winder 7 is wound with the metal wire 6 to be drawn, and the metal wire 6 enters the heating chamber 4 of the heater from the feeding wire winder 7. The feed winder 7 functions to supply the metal wire 6 to be drawn.
In a specific embodiment, the heating chamber 1 is further provided with a driving wire collecting machine 8, the driving wire collecting machine 8 can drive the metal wire 6 to pass through the drawing die 5 to complete the wire drawing process, and the metal wire 6 after wire drawing is collected. As shown by an arrow in FIG. 1, the wire take-up machine 8 is driven to apply a force to the metal wire 6 in a drawing direction, so as to drive the metal wire 6 to move.
In one embodiment, the drawing rate of the hot drawing device is 10-300 m/min, and the drawing wire diameter of the hot drawing device is 5-20 μm. The drawing speed can be regulated and controlled by driving the rotating speed of the wire collecting machine 8, and the drawing wire diameter can be regulated by replacing different drawing dies 5 or enabling the metal wire 6 with drawing to pass through different drawing holes (not shown in the figure) on the drawing dies 5.
In one embodiment, the heating chamber 1 is made of quartz material. Because the quartz material can avoid shielding the alternating magnetic field and reduce impedance, the heating of the Fe iron powder in the SiO2/Fe shell-core spherulite 2 can be smoothly carried out.
In one embodiment, the heat drawing device further comprises a temperature controller 9, wherein the temperature controller 9 is connected to the induction heating coil 3 and can be used to control the output power of the induction heating coil 3 to control the temperature in the heating chamber 4. An operator can input a designated heating temperature on the temperature controller 9 according to the type of the metal wire 6 to be drawn, the drawing wire diameter and the drawing speed.
In one embodiment, the temperature controller 9 is further connected to a thermocouple 10, and the thermocouple 10 is at least partially located in the heating chamber 4 and is configured to detect a temperature in the heating chamber 4 and feed a temperature signal back to the temperature controller 9. In order to match the heating temperature in the heating chamber 4 with the set temperature, the thermocouple 10 can be inserted into the heating chamber 4 and the SiO2/Fe shell-core spherulite 2 is contacted, the real-time temperature in the heating chamber 4 is monitored, the real-time temperature signal is fed back to the temperature controller 9, and the temperature controller 9 compares the real-time temperature signal with the set temperature, so that the heating power is controlled in a closed loop manner, and the accurate temperature control is realized. Wherein, the power 11 of the induction heating coil 3 adopts frequency conversion control, carries out power calculation according to feedback temperature, and outputs the curve of actual temperature and set temperature, and the temperature feedback adopts PID control, thus improving the temperature control precision.
The invention also discloses a drawing method of the ultramicro filament, which comprises the following steps: placing a metal wire 6 to be drawn in a heating chamber 4 of a heater filled with SiO2/Fe shell-core pellets 2; starting the induction heating coil 3 to enable the SiO2/Fe shell-core spherical particle 2 to generate heat, so as to heat the metal wire 6 to be drawn; and then starting the driving wire collecting machine 8 to drive one end of the metal wire 6 to be drawn to pass through the drawing die 5, thereby completing the drawing process of the metal wire 6.
In summary, the hot drawing device and the drawing method of the ultrafine wire of the invention have the beneficial effects that:
the SiO2/Fe shell-core spherulite 2 in the heating cavity 4 cuts alternating magnetic lines to generate eddy current to improve atomic activity through an alternating magnetic field generated by the induction heating coil 3, and the collision friction of atoms moving at high speed is utilized to generate heat energy, so that the process of heating the metal wire 6 to be drawn is realized, and then the metal wire 6 to be drawn is processed into the metal wire 6 with the micro diameter after passing through the drawing die 5. The hot drawing device for the ultramicro wire has the advantages of low energy consumption in the heating process, high temperature control precision and excellent surface quality of the produced metal wire 6 with the ultramicro diameter.
The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. It is not intended to limit the invention to the precise form disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and its practical application to enable one skilled in the art to make and use various exemplary embodiments of the invention and various alternatives and modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the claims and their equivalents.
Claims (10)
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111050219.9A CN113857272A (en) | 2021-09-08 | 2021-09-08 | Thermal drawing device and drawing method of ultrafine filament |
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| CN202111050219.9A CN113857272A (en) | 2021-09-08 | 2021-09-08 | Thermal drawing device and drawing method of ultrafine filament |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116622947A (en) * | 2023-05-11 | 2023-08-22 | 河北大河材料科技有限公司 | A metal wire softening furnace and softening method for continuous drawing |
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Inventor after: Zhang Tao Inventor after: Yuan Hui Inventor after: Liu Qianli Inventor after: Wang Xianjun Inventor after: Zheng Jian Inventor before: Zhang Tao Inventor before: Yuan Hui Inventor before: Liu Qianli Inventor before: Wang Xianjun Inventor before: Zheng Jian |
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