A high temperature medium frequency sintering furnace for preparing tungsten alloy wire

Abstract

The present application provides a high-temperature medium-frequency sintering furnace for tungsten bars used to prepare tungsten alloy wires. The medium-frequency sintering furnace effectively ensures the uniformity of the upper and lower temperatures by adopting an IGBT power supply and upper and lower double coil heating, and has a high heating efficiency; the defect of sintering and bending of tungsten bars used to prepare tungsten alloy wires is eliminated by adopting a support unit to support the tungsten bars; the uniformity of the temperature zone in the tungsten crucible is ensured by heating and evenly dispersing the protective gas entering the furnace shell; the precise control of the internal temperature of the tungsten crucible is improved by the infrared temperature measurement component at the top of the furnace shell. During the sintering process, the pressed tungsten bars are respectively placed in the through holes of the upper tungsten support plate, and the temperature is automatically increased, kept warm, and cooled down for sintering according to the process to obtain tungsten bars for high-strength tungsten alloy wires with uniform composition / organization structure, no bending, and uniform density, which provides a good blank for the subsequent processing of high-strength tungsten alloy wires, reduces material loss, and improves production efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of tungsten alloy processing, and in particular to a tungsten bar high-temperature medium-frequency sintering furnace for preparing tungsten alloy wire. Background Art

[0002] With the rapid development of the photovoltaic field, the demand for silicon wafers has risen sharply. Currently, carbon steel cutting wires are mostly used to cut silicon wafers. In order to meet the "dual carbon" requirements and improve the utilization rate of silicon wafers, higher requirements are placed on the thickness and utilization rate of silicon wafers, requiring thinner silicon wafers and more silicon wafers cut from a single silicon ingot. In turn, the stacking cutting wires require thinner wire diameters and higher strength. However, due to the limited strength of carbon steel wires (when the wire diameter is 0.035mm, the breaking force is 4.0N, and the cutting requirement is ≥5.0N), the cutting wire trap is generally greater than or equal to 0.0045mm, and the breaking force of a smaller wire diameter cannot meet the cutting requirements, which seriously restricts the cutting of thin silicon wafers. In addition, due to the thicker wire diameter, the utilization rate of silicon ingots cannot be further improved.

[0003] Tungsten alloy wire has the characteristics of high strength (wire diameter 0.035mm, breaking force of tungsten alloy wire ≥5.0N) and good plastic deformation ability (can be processed to 0.020-0.030mm). It is an ideal material to basically replace carbon steel cutting wire; but for cutting wire, not only high strength indicators are required, but also the length of single wire must be no less than 50,000 meters; the indicators of silicon wafer cutting wire put forward higher requirements for tungsten alloy wire blanks.

[0004] Uneven composition control of tungsten alloy wire blanks, sintering defects, uneven density, uneven organizational structure, and alloy component segregation directly lead to wire breakage and unstable wire strength during tungsten alloy wire processing. It is impossible to obtain high-performance tungsten alloy wire with a certain length and stable performance, which seriously affects the application of tungsten alloy wire in silicon wafer cutting fields such as photovoltaics and semiconductors.

[0005] Therefore, there is an urgent need to provide a technical solution to the above-mentioned deficiencies in the prior art. Summary of the invention

[0006] The purpose of the present application is to provide a high-temperature medium-frequency sintering furnace for preparing tungsten rods for tungsten alloy wires, so as to solve or alleviate the problems existing in the above-mentioned prior art.

[0007] In order to achieve the above objectives, this application provides the following technical solutions:

[0008] The present application provides a high-temperature medium-frequency sintering furnace for preparing tungsten rods for tungsten alloy wires, comprising: a furnace shell, a sintering unit and a supporting unit; wherein the sintering unit is located in the furnace shell, and the supporting unit is located in the sintering unit; the sintering unit comprises: a tungsten crucible, a first heating coil, a second heating coil, a zirconia insulation upper cover, an alumina insulation upper cover, a zirconia insulation lower cover, an alumina insulation lower cover and an insulation plate tungsten support frame; the alumina insulation lower cover is connected to the inner bottom surface of the furnace shell through a bracket, the zirconia insulation lower cover is placed on the alumina insulation lower cover, and the tungsten crucible is placed on the zirconia insulation lower cover; the insulation plate tungsten support frame is placed on the upper end surface of the tungsten crucible, the zirconia insulation upper cover is placed on the insulation plate tungsten support frame, and the alumina insulation upper cover is placed on the zirconia insulation upper cover; the tungsten crucible is a cylindrical structure with openings at both ends, and the outer side wall of the tungsten crucible is wrapped with a first side insulation layer formed by stacking zirconia bricks, and the first The outer wall of the side insulation layer is wrapped with a second side insulation layer formed by stacking alumina bricks; the support unit is arranged in the cylindrical structure of the tungsten crucible, and the support unit is located on the alumina insulation lower cover, and the tungsten bar to be sintered is placed on the support unit; the upper ends of the first side insulation layer and the second side insulation layer are flush with the alumina insulation upper cover, and the lower ends are flush with the alumina insulation lower cover; the outer periphery of the second side insulation layer spirally surrounds the first heating coil in the vertical direction; wherein, the first heating coil is used to heat the tungsten bar to be sintered in the tungsten crucible; the zirconium oxide insulation lower cover and the alumina insulation lower cover are axially provided with a through air inlet hole to introduce protective gas into the tungsten crucible; the alumina insulation lower cover is formed by stacking alumina bricks, and the second heating coil is arranged in the alumina insulation lower cover; wherein, the second heating coil is used to heat the protective gas entering the tungsten crucible.

[0009] Preferably, an air dividing column is provided at the air inlet of the zirconia thermal insulation lower cover. The air dividing column is a cylindrical boss structure, an air dividing blind hole is axially provided at the bottom, and a plurality of air dividing holes are radially provided on the side wall, and the air dividing holes are connected to the air dividing blind holes.

[0010] Preferably, a first air inlet pipe is adapted and inserted in the air inlet holes of the zirconia insulation lower cover and the alumina insulation lower cover, the upper end of the first air inlet pipe extends from the lower end of the air inlet hole of the zirconia insulation lower cover and abuts against the bottom surface of the gas distribution column; the lower end of the first air inlet pipe extends from the lower end of the air inlet hole of the alumina insulation lower cover and abuts against the upper end of the second air inlet pipe; the lower end of the second air inlet pipe extends out of the bottom of the furnace shell; wherein the first air inlet pipe is a tungsten air inlet pipe.

[0011] Preferably, the insulation plate tungsten support frame includes: connecting columns and tungsten side plates, there are two tungsten side plates, the two tungsten side plates are arranged in parallel, and the two tungsten side plates are connected by a plurality of connecting columns; wherein the two ends of the tungsten side plates are respectively located on the top surface of the tungsten crucible.

[0012] Preferably, the support unit comprises: a lower tungsten support column, a lower tungsten support plate and an upper tungsten support plate; there are multiple lower tungsten support columns, and the multiple lower tungsten support columns are erected on the zirconia thermal insulation lower cover, and the multiple lower tungsten support columns jointly support the lower tungsten support plate; the upper tungsten support plate is located above the lower tungsten support plate, and multiple tungsten bars to be sintered are placed between the lower tungsten support plate and the upper tungsten support plate; wherein the lower end surface of the tungsten bar to be sintered is located on the lower tungsten support plate, and the upper end nut of the tungsten bar to be sintered is connected to the upper tungsten support plate; a plurality of air intake holes are provided on the lower tungsten support plate; the upper tungsten support plate and the lower tungsten support plate are respectively assembled from 4 quarter-circular arc plates.

[0013] Preferably, the bracket includes: a supporting cylinder and a support plate, there are multiple supporting cylinders, and the multiple supporting cylinders are evenly distributed on the inner bottom surface of the furnace shell, and the support plates are placed on the multiple supporting cylinders, and the radial dimensions of the support plates are adapted to the radial dimensions of the furnace shell.

[0014] Preferably, an infrared temperature measuring assembly is provided on the top of the furnace shell, and the temperature measuring probe of the infrared temperature measuring assembly extends into the interior of the furnace shell; correspondingly, a temperature measuring plate is placed on the top surface of the support unit, and the temperature measuring plate is directly opposite to the temperature measuring probe of the infrared temperature measuring assembly.

[0015] Preferably, the furnace shell comprises: a furnace body and a furnace cover; the furnace body is a cylindrical structure with an open upper end, and the furnace cover is sealed and connected to the open end of the furnace body; the furnace body and the furnace cover are both provided with an interlayer cooling cavity.

[0016] Preferably, an exhaust hole and a bursting hole are provided at the bottom of the furnace body, an exhaust valve is installed at the exhaust hole, and an explosion test valve is installed at the bursting hole.

[0017] Preferably, the side wall of the furnace body is provided with an exhaust hole, and a vacuum exhaust valve is installed at the exhaust hole.

[0018] Beneficial effects:

[0019] The embodiment of the present application provides a high-temperature medium-frequency sintering furnace for preparing tungsten alloy wires, comprising: a furnace shell, a sintering unit and a supporting unit. The sintering unit is located in the furnace shell, and the supporting unit is located in the sintering unit; the sintering unit comprises: a tungsten crucible, a first heating coil, a second heating coil, a zirconia insulation upper cover, an alumina insulation upper cover, a zirconia insulation lower cover, an alumina insulation lower cover and an insulation board tungsten support frame, the alumina insulation lower cover is connected to the inner bottom surface of the furnace shell through a bracket, the zirconia insulation lower cover is placed on the alumina insulation lower cover, the tungsten crucible is placed on the zirconia insulation lower cover, the insulation board tungsten support frame is placed on the upper end surface of the tungsten crucible, the zirconia insulation upper cover is placed on the insulation board tungsten support frame, and the alumina insulation upper cover is placed on the zirconia insulation upper cover.

[0020] The tungsten crucible is a cylindrical structure with openings at both ends. The outer wall of the tungsten crucible is wrapped with a first side insulation layer made of zirconium oxide bricks, and the outer wall of the first side insulation layer is wrapped with a second side insulation layer made of alumina bricks. A support unit is arranged in the cylindrical structure of the tungsten crucible, and the support unit is located on the lower cover of the alumina insulation, and the tungsten bar to be sintered is placed on the support unit. The upper ends of the first side insulation layer and the second side insulation layer are flush with the upper cover of the alumina insulation, and the lower ends are flush with the lower cover of the alumina insulation; the outer periphery of the second side insulation layer is spirally wrapped around the first heating coil in the vertical direction, and the first heating coil is used to heat the tungsten bar to be sintered in the tungsten crucible. In this way, a stable sintering environment is provided for the tungsten bar to be sintered, the sintering control of the tungsten bar to be sintered is improved, and defects such as unevenness, sintering defects, uneven density, uneven organizational structure, and alloy component segregation during the sintering process are effectively reduced.

[0021] The zirconia insulation lower cover and the alumina insulation lower cover are axially provided with through air inlet holes to introduce protective gas into the tungsten crucible; the alumina insulation lower cover is made of alumina bricks, and a second heating coil is arranged in the alumina insulation lower cover. The second heating coil is used to heat the protective gas entering the tungsten crucible, thereby increasing the temperature of the protective gas entering the tungsten crucible to make it suitable for the ambient temperature in the tungsten crucible, effectively ensuring that the upper and lower temperatures remain consistent during the sintering process, and ensuring the uniformity of the sintering temperature zone in the tungsten crucible.

[0022] Thereby, the current problems of uneven composition / structure, bending, and uneven density of tungsten rods used to prepare tungsten alloy wires can be effectively solved, providing raw material guarantee for the preparation and processing of high-strength and long-length tungsten alloy wires. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings constituting part of the present application are used to provide a further understanding of the present application. The exemplary embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation on the present application. Among them:

[0024] Figure 1A schematic diagram of the principle of a high-temperature medium-frequency sintering furnace for preparing tungsten alloy wires provided in accordance with some embodiments of the present application;

[0025] Figure 2 A schematic diagram of a high-temperature medium-frequency sintering furnace for preparing tungsten alloy wires according to some embodiments of the present application;

[0026] Figure 3 for Figure 2 A cross-sectional view of a high temperature medium frequency sintering furnace for preparing tungsten alloy wires;

[0027] Figure 4 A schematic diagram of the structure of a tungsten support frame for a thermal insulation board provided according to some embodiments of the present application;

[0028] Figure 5 A schematic diagram of the structure of a gas separation column provided according to some embodiments of the present application;

[0029] Figure 6 for Figure 5 A cross-sectional view of the gas distribution column shown.

[0030] Description of reference numerals:

[0031] 100, furnace shell; 200, sintering unit; 300, support unit; 400, lifting motor; 500, infrared temperature measuring component; 600, water-cooled copper tube; 700, IGBT power supply; 101, furnace cover; 102, furnace body; 202, zirconia insulation lower cover; 201, alumina insulation lower cover; 203, tungsten crucible; 204, first side insulation layer; 205, second side insulation layer; 206, insulation board tungsten support frame; 207, zirconia insulation upper cover; 208, alumina insulation Temperature upper cover; 209, first heating coil; 210, second heating coil; 301, lower tungsten support; 302, lower tungsten support plate; 303, upper tungsten support plate; 401, gas distribution column; 402, first air inlet pipe; 403, second air inlet pipe; 404, temperature measuring plate; 501, supporting cylinder; 502, support plate; 601, exhaust hole; 602, blasting hole; 603, exhaust hole; 216, tungsten side plate; 226, connecting column; 411, gas distribution blind hole; 421, gas distribution hole. DETAILED DESCRIPTION

[0032] The present application will be described in detail below with reference to the accompanying drawings and in conjunction with embodiments. Each example is provided by way of explanation of the present application and does not limit the present application. In fact, it will be clear to those skilled in the art that modifications and variations may be made in the present application without departing from the scope or spirit of the present application. For example, a feature shown or described as a part of an embodiment may be used in another embodiment to produce yet another embodiment. Therefore, it is desired that the present application includes such modifications and variations within the scope of the appended claims and their equivalents.

[0033] High-strength tungsten alloy wire processing can be effectively achieved by improving the uniformity of the tungsten alloy wire blank structure, eliminating sintering defects, and stabilizing the blank composition and performance. However, the existing tungsten rods used for tungsten alloy wire drawing are usually prepared by vertical melting process or sintering process.

[0034] Among them, when the vertical melting process is adopted, (1) the temperature of the tungsten bar is increased by applying current to both ends of the pressed tungsten bar, thereby achieving the purpose of sintering, and the sintering process consumes a lot of energy; (2) only single vertical melting can be performed, and the process efficiency is low; (3) the heat in the middle and at both ends is uneven, and the microstructure of the whole billet is quite different; (4) the temperature is difficult to control, and the alloy components are severely burned; (5) only tungsten bars with a weight of ≤3Kg can be produced, and tungsten bars with a larger weight cannot be produced.

[0035] When using the sintering process, (1) the temperature of the sintering furnace is uneven, and the density of the tungsten bars after sintering varies greatly; (2) the tungsten bars are severely bent after sintering, and microcracks are easily generated during the straightening process, affecting subsequent processing; (3) hydrogen has a great influence on the temperature in the furnace during the sintering process, resulting in differences in the sintered organizational structure; (4) the temperature control accuracy of the sintering process is low, the impurities are not completely volatilized, and the wire breakage during the filament processing process is serious.

[0036] Therefore, both the vertical melting process and the sintering process seriously affect the consistency of the tungsten bars used for drawing tungsten alloy wires, which brings inconvenience to the subsequent processing and use of high-strength tungsten alloy wires. Based on this, the present application proposes a high-temperature medium-frequency sintering furnace for preparing tungsten alloy wires to solve the problems of uneven composition / organization structure, bending, and uneven density of tungsten bars used for preparing tungsten alloy wires, and provide raw material guarantee for the preparation and processing of high-strength and long-length tungsten alloy wires.

[0037] like Figures 1 to 6 As shown, the high temperature medium frequency sintering furnace for preparing tungsten alloy wire comprises: a furnace shell 100, a sintering unit 200 and a supporting unit 300. The sintering unit 200 is located in the furnace shell 100, the supporting unit 300 is located in the sintering unit 200, a plurality of tungsten bars to be sintered are placed in the sintering unit 200 along the vertical direction, and the sintering unit 200 provides heating energy through the IGBT medium frequency power supply 700 to heat and sinter the tungsten bars to be sintered.

[0038] The sintering unit 200 includes: a tungsten crucible 203, a first heating coil 209, a second heating coil 210, a zirconia insulation upper cover 207, an alumina insulation upper cover 208, a zirconia insulation lower cover 202, an alumina insulation lower cover 201 and an insulation plate tungsten support frame 206. The alumina insulation lower cover 201 is connected to the inner bottom surface of the furnace shell 100 through a bracket, the zirconia insulation lower cover 202 is placed on the alumina insulation lower cover 201, the tungsten crucible 203 is placed on the zirconia insulation lower cover 202, the insulation plate tungsten support frame 206 is placed on the upper end surface of the tungsten crucible 203, the zirconia insulation upper cover 207 is placed on the insulation plate tungsten support frame 206, and the alumina insulation upper cover 208 is placed on the zirconia insulation upper cover 207.

[0039] The tungsten crucible 203 is a cylindrical structure with two ends open. The outer wall of the tungsten crucible 203 is wrapped with a first side insulation layer 204 made of zirconium oxide bricks, and the outer wall of the first side insulation layer 204 is wrapped with a second side insulation layer 205 made of alumina bricks. A support unit 300 is provided in the cylindrical structure of the tungsten crucible 203, and the support unit 300 is located on the alumina insulation lower cover 201, and the tungsten bar to be sintered is placed on the support unit 300. The upper ends of the first side insulation layer 204 and the second side insulation layer 205 are flush with the alumina insulation upper cover 208, and the lower ends are flush with the alumina insulation lower cover 201. The outer periphery of the second side insulation layer 205 spirally surrounds the first heating coil 209 in the vertical direction. The terminal of the first heating coil 209 extends from the side wall of the furnace shell 100 and is connected to the IGBT medium frequency power supply 700 through the water-cooled copper tube 600. The eddy current generated heats the tungsten bar to be sintered in the tungsten crucible 203, effectively improving the heating efficiency. At the same time, the first heating coil 209 is cooled by the water-cooled copper tube 600; the first heating coil 209 is divided into two parts, the upper and lower parts, and the terminal of the two parts of the heating coils are parallel and both extend from the side wall of the furnace shell 100 and are connected to the water-cooled copper tube 600, thereby effectively ensuring the uniformity of the upper and lower temperatures in the tungsten crucible 203.

[0040] The zirconia insulation lower cover 202 and the alumina insulation lower cover 201 are axially provided with through air inlet holes to introduce protective gas into the tungsten crucible 203; the alumina insulation lower cover 201 is made of alumina bricks, and a second heating coil 210 is arranged in the alumina insulation lower cover 201, and the connection section of the second heating coil 210 extends from the bottom of the furnace shell 100. The second heating coil 210 heats the protective gas entering the tungsten crucible 203, thereby increasing the temperature of the protective gas entering the tungsten crucible 203 to make it suitable for the ambient temperature in the tungsten crucible 203, effectively ensuring that the upper and lower temperatures remain consistent during the sintering process, and ensuring the uniformity of the sintering temperature zone in the tungsten crucible 203.

[0041] A gas separation column 401 is provided at the gas inlet of the zirconia insulation lower cover 202. The gas separation column 401 is a cylindrical boss structure, and a gas separation blind hole 411 is provided in the axial direction at the bottom, and a plurality of gas separation holes 421 are provided in the radial direction on the side wall, and the gas separation holes 421 are connected with the gas separation blind holes 411. Thus, the protective gas enters from the gas inlet, and under the action of the gas separation column 401, enters the tungsten crucible 203 through the gas separation holes 421 on the gas separation column 401, and simultaneously spreads from the middle of the tungsten crucible 203 to the surroundings, thereby effectively improving the uniformity of the protective gas in the tungsten crucible 203.

[0042] At the same time, the first air inlet pipe 402 is adapted and inserted in the air inlet holes of the zirconia insulation lower cover 202 and the alumina insulation lower cover 201. The upper end of the first air inlet pipe 402 extends from the lower end of the air inlet hole of the zirconia insulation lower cover 202 and abuts against the bottom surface of the gas separation column 401; the lower end of the first air inlet pipe 402 extends from the lower end of the air inlet hole of the alumina insulation lower cover 201 and abuts against the upper end of the second air inlet pipe 403, and the lower end of the second air inlet pipe 403 extends out of the bottom of the furnace shell 100. The second heating coil 210 located in the zirconia insulation lower cover 202 generates eddy currents to heat the first air inlet pipe 402 (tungsten air inlet pipe) made of tungsten material, thereby increasing the temperature of the protective gas entering the tungsten crucible 203. One end of the second air inlet pipe 403 extending into the furnace shell 100 is connected to the bottom of the furnace shell 100 through a connecting cover, and the end can be connected to a hydrogen air inlet valve and a nitrogen air inlet valve at the same time to control the introduction of protective gas through the hydrogen valve and the nitrogen air inlet valve respectively.

[0043] In the present application, a tungsten support frame 206 of an insulation plate is placed on the top surface of the tungsten crucible 203, and the zirconia insulation upper cover 207 and the alumina insulation upper cover 208 are supported by the tungsten support frame 206 of the insulation plate, so as to effectively ensure the overall strength of the zirconia insulation upper cover and avoid brittle cracking of the zirconia insulation upper cover. Among them, the tungsten support frame 206 of the insulation plate includes: a connecting column 226 and a tungsten side plate 216, and there are two tungsten side plates 216, which are arranged in parallel, and the two tungsten side plates 216 are connected by multiple connecting columns 226, and the two ends of the tungsten side plates 216 are respectively located on the top surface of the tungsten crucible 203. Here, the connecting column 226 and the tungsten side plate 216 are fixed by tungsten wire pins.

[0044] In the present application, the tungsten rod is supported by the support unit 300, which effectively eliminates the defect of sintering bending of the tungsten rod used to prepare the tungsten alloy wire. Specifically, the support unit 300 includes: a lower tungsten support column 301, a lower tungsten support plate 302 (thickness ) and the upper tungsten support plate 303 (thickness ). There are multiple lower tungsten pillars 301, which are erected on the zirconia insulation lower cover 202, and the multiple lower tungsten pillars 301 jointly support the lower tungsten support plate 302. The lower tungsten support plate 302 and the upper tungsten support plate 303 are placed side by side in the vertical direction, and the tungsten bar to be sintered is placed between the lower tungsten support plate 302 and the upper tungsten support plate 303. That is, the lower end surface of the tungsten bar to be sintered is located on the lower tungsten support plate 302, and the upper end nut of the tungsten bar to be sintered is connected to the upper tungsten support plate 303. In a specific example, the tungsten bar is in the shape of a body, the upper part passes through the corresponding through hole of the upper tungsten support plate 303, and is provided with a connecting thread.

[0045] During installation, firstly, the lower tungsten pillar 301 is evenly placed on the zirconia insulation lower cover 202, and then the lower tungsten support plate 302 composed of quarter-circular arc plates is horizontally placed on the lower tungsten pillar 301; the tungsten bar to be sintered is fixed on the quarter-circular arc plate of the upper tungsten support plate 303 by nuts, and after all the tungsten bars to be sintered are fixed, the tungsten bar to be sintered is connected to the upper tungsten support plate and placed on the lower tungsten support plate 302, and the four quarter-circular arc plates of the upper tungsten support plate 303 support each other in the horizontal direction.

[0046] A plurality of air inlet holes (aperture diameter ), the protective gas entering through the gas distribution column 401 flows between the multiple lower tungsten pillars 301, and flows upward through the air inlet holes on the lower tungsten support plate 302. On the upper tungsten support plate 303, there are multiple mounting holes, and the upper end of the tungsten bar to be sintered extends out of the upper end surface of the upper tungsten support plate 303 through the mounting holes and is fixed on the upper tungsten support plate 303 by nuts.

[0047] In a specific example, the upper tungsten support plate 303 and the lower tungsten support plate 302 are respectively assembled from four quarter-circular arc plates, or two semicircular plates, thereby effectively reducing the cost and difficulty of processing, improving the convenience of maintenance, and facilitating installation.

[0048] In the present application, the sintering unit 200 is seated on the inner bottom surface of the furnace shell 100 through a bracket, wherein the bracket includes: a plurality of supporting cylinders 501 and a support plate 502, the plurality of supporting cylinders 501 are evenly distributed on the inner bottom surface of the furnace shell 100, the top surfaces of the plurality of supporting cylinders 501 are flush, and the support plate 502 is placed, and the radial dimension of the support plate 502 is adapted to the radial dimension of the furnace shell 100 to effectively ensure the airtightness of the space where the sintering unit 200 is located.

[0049] An infrared temperature measuring assembly 500 is arranged at the top of the furnace shell 100, and the temperature measuring probe of the infrared temperature measuring assembly 500 extends into the furnace shell 100; correspondingly, a temperature measuring plate 404 is placed on the top surface of the support unit 300, and the temperature measuring plate 404 faces the infrared temperature measuring probe. In other words, through holes are respectively provided on the zirconia insulation cover 207 and the alumina insulation cover 208 facing the temperature measuring probe ( ), so that the temperature measuring probe can monitor the sintering temperature through the plane reflection of the temperature measuring plate 404, and measure the temperature inside the tungsten crucible 203 in real time; improve the temperature measurement accuracy, and help to control the internal temperature of the tungsten crucible 203 according to the set program.

[0050] In the present application, the furnace shell 100 is a split structure, including: a furnace body 102 and a furnace cover 101. The furnace body 102 is a cylindrical structure with an open upper end, and the furnace cover 101 is sealed and connected to the open end of the furnace body 102; both the furnace body 102 and the furnace cover 101 are provided with an interlayer cooling cavity, and the furnace body 102 and the furnace shell 100 are respectively provided with a water inlet and a water outlet to pass cooling circulating water into the corresponding interlayer cooling cavity to cool the furnace shell 100.

[0051] At the same time, an exhaust hole 601 and a bursting hole 602 are provided at the bottom of the furnace body 102, and an exhaust hole 603 is provided on the side wall of the furnace body 102. An exhaust valve is installed at the exhaust hole 601, an explosion test valve and a bursting disc are installed at the bursting hole 602, and a vacuum exhaust valve is installed at the exhaust hole 603. Thus, the gas circulation inside the furnace shell 100 can be realized through the exhaust valve; the explosion test valve can be used to conduct an explosion test on the protective gas introduced into the furnace shell 100, and when the hydrogen burns in the furnace shell 100, the bursting disc ruptures to quickly relieve the pressure on the furnace shell 100 to avoid accidents; the external vacuum unit realizes the vacuum extraction in the furnace shell 100 during the sintering process through the vacuum exhaust valve, so that the vacuum degree in the furnace shell 100 is not lower than .

[0052] In addition, a lifting motor 400 is provided on the outer side of the furnace shell 100 . The lifting motor 400 drives the furnace cover 101 to move up and down through a lifting screw to reduce the work intensity when installing the furnace cover 101 .

[0053] In the present application, by adopting IGBT power supply and upper and lower double coil heating, the uniformity of upper and lower temperatures is effectively guaranteed. Due to the adoption of IGBT power supply, the heating efficiency is relatively high. By adopting the support unit 300 to support the tungsten bar, the defect of sintering and bending of the tungsten bar used for preparing tungsten alloy wire is eliminated. By heating and evenly dispersing the protective gas (hydrogen) entering the furnace shell 100, the uniformity of the temperature zone in the tungsten crucible 203 is ensured. The infrared temperature measuring component 500 at the top of the furnace shell 100 improves the precise control of the internal temperature of the tungsten crucible 203. During the sintering process, the pressed tungsten bars are respectively placed in the through holes of the upper tungsten support plate 303, and the temperature is automatically increased, kept warm, and cooled down according to the process to obtain a tungsten bar for high-strength tungsten alloy wire with uniform composition / organization structure, no bending, and uniform density, which provides a good blank for the subsequent processing of high-strength tungsten alloy wire, reduces material loss, and improves production efficiency.

[0054] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A high temperature medium frequency sintering furnace for preparing tungsten alloy wire, characterized in that: include: A furnace shell, a sintering unit and a supporting unit; wherein the sintering unit is located in the furnace shell, and the supporting unit is located in the sintering unit; The sintering unit comprises: a tungsten crucible, a first heating coil, a second heating coil, a zirconia insulation upper cover, an alumina insulation upper cover, a zirconia insulation lower cover, an alumina insulation lower cover and an insulation board tungsten support frame; The alumina insulation lower cover is connected to the inner bottom surface of the furnace shell through a bracket, the zirconia insulation lower cover is placed on the alumina insulation lower cover, and the tungsten crucible is placed on the zirconia insulation lower cover; the insulation board tungsten support frame is placed on the upper end surface of the tungsten crucible, the zirconia insulation upper cover is placed on the insulation board tungsten support frame, and the alumina insulation upper cover is placed on the zirconia insulation upper cover; The tungsten crucible is a cylindrical structure with two ends open, the outer wall of the tungsten crucible is wrapped with a first side insulation layer made of zirconium oxide bricks, and the outer wall of the first side insulation layer is wrapped with a second side insulation layer made of alumina bricks; The support unit is arranged in the cylindrical structure of the tungsten crucible, and the support unit is located on the alumina insulation lower cover, and the tungsten bar to be sintered is placed on the support unit; The upper ends of the first side insulation layer and the second side insulation layer are flush with the alumina insulation upper cover, and the lower ends are flush with the alumina insulation lower cover; the outer periphery of the second side insulation layer spirally surrounds the first heating coil in a vertical direction; wherein the first heating coil is used to heat the tungsten bar to be sintered in the tungsten crucible; The zirconium oxide thermal insulation lower cover and the aluminum oxide thermal insulation lower cover are provided with a through air inlet hole in the axial direction to allow protective gas to be introduced into the tungsten crucible; The alumina insulation lower cover is made of alumina bricks, and the second heating coil is arranged in the alumina insulation lower cover; wherein the second heating coil is used to heat the protective gas entering the tungsten crucible.

2. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 1, characterized in that: An air dividing column is arranged at the air inlet of the zirconia thermal insulation lower cover. The air dividing column is a cylindrical boss structure, an air dividing blind hole is arranged axially at the bottom, and a plurality of air dividing holes are arranged radially on the side wall. The air dividing holes are connected with the air dividing blind holes.

3. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 2, characterized in that: A first air inlet pipe is adapted and inserted in the air inlet holes of the zirconia insulation lower cover and the alumina insulation lower cover, the upper end of the first air inlet pipe extends from the lower end of the air inlet hole of the zirconia insulation lower cover and abuts against the bottom surface of the gas distribution column; the lower end of the first air inlet pipe extends from the lower end of the air inlet hole of the alumina insulation lower cover and abuts against the upper end of the second air inlet pipe; the lower end of the second air inlet pipe extends out of the bottom of the furnace shell; wherein the first air inlet pipe is a tungsten air inlet pipe.

4. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 1, characterized in that: The insulation board tungsten support frame includes: a connecting column and a tungsten side plate. There are two tungsten side plates, which are arranged in parallel and connected by a plurality of connecting columns. The two ends of the tungsten side plates are respectively located on the top surface of the tungsten crucible.

5. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 1, characterized in that: The support unit comprises: a lower tungsten support column, a lower tungsten support plate and an upper tungsten support plate; There are multiple lower tungsten pillars, which are erected on the zirconia insulation lower cover, and the multiple lower tungsten pillars jointly support the lower tungsten support plate; the upper tungsten support plate is located above the lower tungsten support plate, and multiple tungsten bars to be sintered are placed between the lower tungsten support plate and the upper tungsten support plate; Wherein, the lower end surface of the tungsten bar to be sintered is located on the lower tungsten support plate, and the upper end nut of the tungsten bar to be sintered is connected to the upper tungsten support plate; the lower tungsten support plate is provided with a plurality of air inlet holes; The upper tungsten support plate and the lower tungsten support plate are respectively assembled from four quarter-circular arc plates.

6. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 1, characterized in that: The bracket includes: a supporting cylinder and a supporting plate. There are multiple supporting cylinders, and the multiple supporting cylinders are evenly distributed on the inner bottom surface of the furnace shell. The supporting plates are placed on the multiple supporting cylinders, and the radial size of the supporting plates is compatible with the radial size of the furnace shell.

7. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 1, characterized in that: An infrared temperature measuring component is arranged at the top of the furnace shell, and a temperature measuring probe of the infrared temperature measuring component extends into the interior of the furnace shell; Correspondingly, A temperature measuring plate is placed on the top surface of the support unit, and the temperature measuring plate is directly facing the temperature measuring probe of the infrared temperature measuring component.

8. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 1, characterized in that: The furnace shell comprises: a furnace body and a furnace cover; The furnace body is a cylindrical structure with an open upper end, and the furnace cover is sealed and connected to the open end of the furnace body; The furnace body and the furnace cover are both provided with an interlayer cooling cavity.

9. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 8, characterized in that: An exhaust hole and a bursting hole are provided at the bottom of the furnace body. An exhaust valve is installed at the exhaust hole, and an explosion test valve is installed at the bursting hole.

10. The high temperature medium frequency sintering furnace for preparing tungsten alloy wire according to claim 8, characterized in that: The side wall of the furnace body is provided with an exhaust hole, and a vacuum exhaust valve is installed at the exhaust hole.

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