Gas heating ten-die wire drawing machine and high-performance tungsten wire drawing process

Abstract

The present application relates to tungsten wire drawing processing technical field, provide a kind of gas heating ten die drawing machine and high-performance tungsten wire drawing process.Gas heating ten die drawing machine includes rack and electrical controller, rack is sequentially provided with magnetic damping pay-off reel, guide wheel, natural gas furnace, drawing die carrier, tower and servo wire collecting disc along wire processing path;Natural gas furnace includes 10 heating units, rack is provided with electrical proportional valve, and electrical proportional valve signal is connected to electrical controller;The temperature sensor is arranged above the heating unit, and the temperature sensor signal is connected to the electrical controller, and the temperature sensor is used to monitor the temperature of wire in real time;A kind of high-performance tungsten wire drawing process, comprising the following steps: S1, rough drawing;S2, medium drawing;S3, fine drawing;Step S1 is implemented using the above gas heating ten die drawing machine;Through the synergistic innovation of equipment and process, the effect of improving tungsten wire strength, improving tungsten wire performance and reducing breakage rate is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tungsten wire drawing processing, and particularly relates to a gas heating ten-die wire drawing machine and a high-performance tungsten wire drawing process. BACKGROUND

[0002] Tungsten wire has significant advantages in replacing traditional high-carbon steel wire as a photovoltaic cutting bus, but there is still a certain breakage rate at the cutting end. In the traditional drawing process of tungsten wire, 0.39mm tungsten wire is selected, and the bus is first subjected to 1600-1700 degree temperature flame annealing, then subjected to electric heating ten-die wire drawing machine, and the tungsten wire is coarsely drawn to 0.16mm tungsten wire at a temperature of 800-850 degrees, then subjected to electric heating ten-die wire drawing machine, and the tungsten wire is drawn to 0.06-0.08mm tungsten wire at a temperature of 400-500 degrees, and finally subjected to electric heating ten-die wire drawing machine, and the tungsten wire is finely drawn to 0.016-0.028mm tungsten wire at a temperature of 300-400 degrees. At present, the cutting data of 0.028mm-0.030mm bus maintains a breakage rate of 6%-10%.

[0003] For the related technology in the above process, the electric heating ten-die wire drawing machine contacts and heats the tungsten wire surface during the drawing of 0.39mm tungsten wire to 0.16-0.18mm tungsten wire. Since the tungsten wire is thin, the tungsten wire is difficult to heat uniformly, and the tungsten wire center point and surface organization refinement degree are inconsistent, resulting in uneven tungsten wire organization refinement. In addition, in the traditional process, annealing is needed to eliminate work hardening, and at the same time, the drawing strength of the same material is lower, resulting in insufficient surface strength of the tungsten wire.

[0004] Therefore, the cutting bus obtained by drawing tungsten wire by the traditional equipment and process has the problems of uneven organization refinement, insufficient surface strength and high breakage rate. SUMMARY

[0005] The present application aims to provide a gas heating ten-die wire drawing machine and a high-performance tungsten wire drawing process to solve the problems of uneven tungsten wire organization refinement, insufficient surface strength and high breakage rate.

[0006] In a first aspect, the present application provides a gas-heated ten-die wire drawing machine, comprising a rack and an electrical controller, the rack is sequentially provided with a magnetic damping pay-off reel, a guide wheel, a natural gas furnace, a die holder, a capstan and a servo wire collecting reel along a wire processing path, the natural gas furnace comprises ten heating units with independent temperature control, the rack is further provided with an electrical proportional valve, the electrical proportional valve is used to adjust the mixing ratio of natural gas and compressed air in the heating unit, the electrical proportional valve is signal connected with the electrical controller, a temperature measuring sensor is further provided above the heating unit, the temperature measuring sensor is signal connected with the electrical controller, the temperature measuring sensor is used to monitor the wire temperature in real time and feed back to the electrical controller, the electrical controller dynamically controls the electrical proportional valve based on the PID algorithm, so that the wire temperature in the heating unit is maintained within the range of set value ± 5℃.

[0007] As an optimization of the gas-heated ten-die wire drawing machine, a jitter prevention stabilizing assembly is provided between the magnetic damping pay-off reel and the guide wheel, the jitter prevention stabilizing assembly comprises a support arm, a fixed pulley and a floating pulley, the support arm is fixedly connected to the rack, the fixed pulley is detachably connected to one end of the support arm close to the guide wheel, a vertical guide rail is provided on the support arm, the floating pulley is slidingly connected to the vertical guide rail, and the wire is arranged in an "S" shape or "Z" shape path around the fixed pulley and the floating pulley.

[0008] As an optimization of the gas-heated ten-die wire drawing machine, a graphite emulsion coating box is provided between the guide wheel and the natural gas furnace, a plurality of through lubricating grooves are provided in the graphite emulsion coating box, and the through lubricating grooves are provided for the wire.

[0009] As an optimization of the gas-heated ten-die wire drawing machine, an adjustable support is provided on the rack, the adjustable support comprises a fixed plate and a rotating frame, the temperature measuring sensor is fixedly connected to the rotating frame, the side wall of the rotating frame is rotatably connected to the fixed plate, an arc-shaped limiting hole is provided on the fixed plate, and the arc-shaped limiting hole is used to constrain the rotation angle of the rotating frame.

[0010] As an optimization of the gas-heated ten-die wire drawing machine, a translation guide rail is provided on the rack, the sliding direction of the translation guide rail is perpendicular to the wire processing path, and the translation guide rail is used to drive the servo wire collecting reel to reciprocate.

[0011] In a second aspect, the present application provides a high-performance tungsten wire drawing process, comprising the following steps:

[0012] S1, rough drawing: the tungsten wire with the lanthanum oxide content of 0.60%-0.80%, the intensity of 2300-2500 MPa and the wire diameter of 0.39 mm is not annealed, and is drawn to the tungsten wire with the wire diameter of 0.16-0.18 mm at the temperature of 900-950 DEG C with the area reduction of 16%-22%;

[0013] S2, medium drawing: the tungsten wire after the rough drawing is drawn to the tungsten wire with the wire diameter of 0.06-0.08 mm at the temperature of 400-500 DEG C with the area reduction of 16%-22%;

[0014] S3, fine drawing: the tungsten wire after the medium drawing is drawn to the tungsten wire with the target wire diameter of 0.028-0.030 mm at the temperature of 300-400 DEG C with the area reduction of 16%-22%;

[0015] The step S1 is implemented by using the gas heating ten-die wire drawing machine of the first aspect.

[0016] As an optimization of the high-performance tungsten wire drawing process, the tungsten wire obtained by the step S3 has the intensity of greater than or equal to 6500 MPa and the breakage rate of less than or equal to 2%.

[0017] Compared with the prior art, the application has the beneficial effects that:

[0018] (1) The gas heating ten-die wire drawing machine provided by the application directly heats the wire through 10 heating units with independent temperature control, and forms a PID closed loop control with the electrical controller, the temperature sensor and the electrical proportional valve, so that the temperature difference of the wire full section is less than or equal to 5 DEG C, thereby solving the problem of core coarse grains caused by uneven temperature, promoting the tungsten wire organization to be refined and uniform, and significantly reducing the breakage rate of the tungsten wire.

[0019] (2) The high-performance tungsten wire drawing process provided by the application cancels the traditional annealing step at 1600 DEG C-1700 DEG C, directly uses the gas heating ten-die wire drawing machine for rough drawing, and initiates the dynamic recrystallization rough drawing process at 900-950 DEG C, so as to avoid the grain coarsening defects caused by high-temperature annealing, make the tungsten wire grain uniform and refined to 1.5 mu m, and thereby make the tungsten wire intensity higher than that of the tungsten wire by the traditional process. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiment or the prior art description. Obviously, the drawings in the following description only show some embodiments of the application, and other drawings can also be obtained by those skilled in the art without any creative labor.

[0021] Figure 1 It is a whole structure schematic diagram of the gas heating ten-die wire drawing machine of the embodiment of the application.

[0022] Figure 2 It is the overall structure schematic diagram of graphite emulsion coating box of the embodiment of the application;

[0023] Figure 3 It is the exploded structure schematic diagram of adjustable support of the embodiment of the application;

[0024] Figure 4 It is the flow chart of a high-performance tungsten wire drawing process of the embodiment of the application.

[0025] In the figure: 1, rack; 2, electrical controller; 3, magnetic damping pay-off reel; 4, guide wheel; 5, natural gas furnace; 51, heating unit; 52, electrical proportional valve; 53, temperature measuring sensor; 54, adjustable support; 541, fixed plate; 542, rotating frame; 543, arc-shaped limiting hole; 6, wire drawing die frame; 7, tower wheel; 8, servo wire collecting reel; 9, anti-shake stabilizing assembly; 91, support arm; 92, fixed pulley; 93, floating pulley; 94, vertical guide rail; 10, graphite emulsion coating box; 101, through lubrication groove; 102, water inlet pipeline; 103, water outlet pipeline; 11, translation guide rail. DETAILED DESCRIPTION

[0026] In order to make the technical solutions and advantages of the application clearer, the following will combine specific embodiments and the drawings of the specification to make further detailed description of the application and its beneficial effects, but the embodiments of the application are not limited thereto.

[0027] In the description of the application, unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting", "fixing" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral; it can be mechanical connection, or electrical connection; it can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements or interaction relationship of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the application can be understood according to specific circumstances.

[0028] The standard parts used in the application can be purchased from the market, and the special-shaped parts can be ordered according to the description and the drawings, and the specific connection mode of each part adopts the conventional means such as bolt, rivet and welding in the prior art, the mechanical parts and equipment adopt the conventional type in the prior art, and the circuit connection adopts the conventional connection mode in the prior art, which will not be described in detail here.

[0029] The following will combine the drawings of the application Figures 1-4 The application will be further described in detail.

[0030] EMBODIMENT

[0031] In a first aspect, the application provides a gas heating ten-die wire drawing machine, which adopts the following technical scheme:

[0032] With reference to Figure 1 The gas heating ten-die wire drawing machine comprises a rack 1 and an electrical controller 2. The electrical controller 2 is installed on the tabletop of the rack 1. The electrical controller 2 is a PLC (Programmable Logic Controller). A PID (Proportional Integral Derivative) algorithm program is programmed on the PLC. A magnetism damping pay-off reel 3, a guide wheel 4, a natural gas furnace 5, a die holder 6, a capstan 7 and a servo wire collecting reel 8 are sequentially arranged and installed on the tabletop of the rack 1 along a wire processing path. The natural gas furnace 5 comprises ten independent heating units 51. Each heating unit 51 is an independent station. Each heating unit 51 is heated individually by a flame generated by mixing natural gas and compressed air. The heating unit 51 heats the wire by heat radiation. Ten wire drawing dies are installed on the die holder 6 in correspondence. The heated wire is drawn and processed. An electrical proportional valve 52 is installed at the bottom of the rack 1. The electrical proportional valve 52 is a double-channel magnetic flux valve. Natural gas and compressed air are respectively passed through the two channels. The electrical proportional valve 52 is signal connected to the electrical controller 2. The mixing ratio of the natural gas and the compressed air is accurately adjusted by the instruction of the electrical controller 2. The combustion temperature of the heating unit 51 is accurately controlled. A separate temperature measuring sensor 53 is installed above each heating unit 51. The temperature of the wire in the heating unit 51 is detected in real time. In this embodiment, the temperature measuring sensor 53 is an infrared temperature measuring instrument. The temperature measuring sensor 53 is signal connected to the electrical controller 2. The temperature of the wire in the heating unit 51 is fed back to the electrical controller 2 in real time. The electrical controller 2 dynamically controls the electrical proportional valve 52 to adjust the mixing ratio of the natural gas and the compressed air in real time according to the signal of the temperature measuring sensor 53 by the PID algorithm program. A closed loop temperature control is formed. The uniformity of the wire heating temperature is improved.

[0033] In the preferred embodiment of the application, with reference to Figure 1The anti-shake stabilizing assembly 9 is fixedly installed between the magnetic damping pay-off disc 3 and the guide wheel 4, and includes a support arm 91, a fixed pulley 92 and a floating pulley 93. One end of the support arm 91 is fixedly installed on the outer wall of the bearing seat of the magnetic damping pay-off disc 3, and the other end of the support arm 91 extends towards the guide wheel 4. The support arm 91 is transversely provided with a plurality of first mounting holes, the fixed pulley 92 is insertedly installed in one of the first mounting holes, and the fixed pulley 92 is detachably installed on the end of the support arm 91 close to the guide wheel 4. A vertical guide rail 94 is detachably fixedly connected to the middle portion of the support arm 91, and the floating pulley 93 is slidingly installed on the vertical guide rail 94 and vertically ascends and descends. The wire drawn out from the magnetic damping pay-off disc 3 passes through the floating pulley 93 and the fixed pulley 92 in sequence, and forms an "S" shape or a "Z" shape path between the floating pulley 93 and the fixed pulley 92, thereby reducing the up-and-down shaking of the wire.

[0034] In the preferred embodiments of the present application, with reference to Figure 1 and Figure 2 The graphite emulsion coating box 10 is fixedly installed between the guide wheel 4 and the natural gas grate 5, and is externally connected with a water inlet pipeline 102 and a water outlet pipeline 103. A plurality of through lubricating grooves 101 are integrally formed in the graphite emulsion coating box 10, the bottom of each through lubricating groove 101 is provided with a spray port, the spray port is communicated with the water inlet pipeline 102, the graphite emulsion lubricant is injected through the water inlet pipeline 102, sprayed upwards through the spray port, and filled in the through lubricating groove 101, and the overflowed graphite emulsion lubricant in the through lubricating groove 101 is discharged through the water outlet pipeline 103, re-injected into the water inlet pipeline 102 through an additional circulating path, so as to form a self-circulation of the lubricant in the graphite emulsion coating box 10. When the wire passes through the through lubricating groove 101, the graphite emulsion lubricant in the through lubricating groove 101 is coated on the wire, so as to improve the smoothness of the wire drawing process, and is beneficial to improve the drawing efficiency.

[0035] In the preferred embodiments of the present application, with reference to Figure 3The adjustable support 54 is also fixedly installed on the rack 1 and includes a fixed plate 541 and a rotating frame 542. The bottom end of the fixed plate 541 is fixedly installed on the rack 1, and the top end of the fixed plate 541 is provided with a circular hole and an arc-shaped limiting hole 543. The rotating frame 542 includes an angle iron and a square plate, one end of the angle iron is welded to the square plate, a plurality of temperature sensors 53 are fixedly installed on the main body of the angle iron, the positions of the plurality of temperature sensors 53 correspond to the plurality of heating units 51 on the natural gas furnace 5 one by one, and at least two studs are installed on the square plate, one of which passes through the circular hole of the fixed plate 541 to form a rotation center, and the other passes through the arc-shaped limiting hole 543 to slide or lock, so that the rotating frame 542 is rotatably installed on the fixed plate 541, the rotating angle of the rotating frame 542 is limited by the arc-shaped limiting hole 543, and the temperature measurement direction of the temperature sensor 53 is adjusted, so that the temperature of the heating unit 51 at different positions is monitored, and the stability of the temperature at all positions on the processing path of the heating unit 51 is facilitated.

[0036] In the preferred embodiment of the present application, with reference to Figure 1 The rack 1 is also provided with a translation guide rail 11, the sliding direction of the translation guide rail 11 is perpendicular to the processing path of the wire, and the bearing seat of the servo wire collecting disc 8 is fixedly installed on the sliding seat of the translation guide rail 11. The servo wire collecting disc 8 reciprocates with the translation guide rail 11, so that the wire is uniformly wound on the servo wire collecting disc 8.

[0037] The implementation principle of the device is that the innovative heat source form and closed-loop control system realize high-precision and uniform control of the temperature of the tungsten wire drawing process. Specifically, the 10 independent temperature control heating units 51 of the natural gas furnace 5 adopt natural gas and compressed air mixed combustion to generate high-temperature flame, and mainly heat the wire in a non-contact manner through convection and thermal radiation. Compared with the traditional electric heating die head drawing machine which heats the wire in a contact manner through a conductive wheel or a die, the problem of inherent unevenness of contact heating is fundamentally solved, and the uniformity of the temperature of the whole cross section of the wire is realized. At the same time, the temperature sensor 53 located above each heating unit 51 monitors the actual temperature of the wire in real time and feeds back the signal to the electrical controller 2. The electrical controller 2 is provided with a PID algorithm program, which dynamically calculates and outputs a control signal to the electrical proportional valve 52 according to the deviation between the set temperature and the actual temperature. The electrical proportional valve 52 accurately adjusts the mixing ratio of natural gas and compressed air entering the heating unit 51, so as to immediately adjust the temperature and heat output of the combustion flame. This closed-loop control system ensures that the temperature of the wire can be stably maintained within a narrow range of ±5℃ of the set value when passing through each heating unit 51, and lays a foundation for the equipment for the uniform refinement and strength improvement of the tungsten wire in the subsequent drawing process.

[0038] In a second aspect, the application provides another high-performance tungsten wire drawing process, which comprises the following steps according to the following table:

[0039] S1, rough drawing: drawing tungsten wire without annealing, with lanthanum oxide content of 0.60%-0.80%, strength of 2300-2500 MPa, and wire diameter of 0.39 mm, to tungsten wire with wire diameter of 0.16-0.18 mm at a temperature of 900-950 ℃ and a reduction of 16%-22%;

[0040] S2, medium drawing: drawing the tungsten wire after rough drawing to tungsten wire with wire diameter of 0.06-0.08 mm at a temperature of 400-500 ℃ and a reduction of 16%-22%;

[0041] S3, fine drawing: drawing the tungsten wire after medium drawing to tungsten wire with target wire diameter of 0.028-0.030 mm at a temperature of 300-400 ℃ and a reduction of 16%-22%.

[0042] Further, the step S1 is implemented by using a gas heating ten-die wire drawing machine, and the temperature control accuracy is ±5 ℃.

[0043] Further, the tungsten wire obtained in the step S3 has a strength of ≥6500 MPa and a wire breaking rate of ≤2%.

[0044] The implementation principle of the process is that the step of traditional process “high-temperature annealing at 1600-1700 ℃” is cancelled, and the “dynamic recrystallization rough drawing process at 900-950 ℃” is directly implemented in the rough drawing stage. In the process of metal plastic deformation, when the deformation temperature and strain rate meet certain conditions, deformation and recrystallization occur synchronously. The first recrystallization starting temperature of tungsten is about 800 ℃. The temperature range of the step S1 is higher than the first recrystallization starting temperature of tungsten, but far lower than the traditional annealing temperature. The tungsten wire is drawn at this temperature, and the dislocation accumulation in the tungsten wire due to deformation will trigger dynamic recrystallization. New grains are nucleated and grown in real time during the deformation process, realizing the ultra-fining and uniformization of the tungsten wire structure.

[0045] Compared with the traditional process, the progress effect of the process is specifically manifested as follows: the grain size is refined from 2-3 μm to 1.5 μm, the radial uniformity is improved, the structure and performance of the tungsten wire are improved, the strength of the tungsten wire product is increased by about 200 MPa, the wire breaking rate is reduced by 8 percentage points, the mechanical properties of the tungsten wire are improved, the process step and cost of annealing are saved, the energy is saved by 40%, the production cycle is shortened, and the production cost is reduced.

[0046] Experimental example

[0047] Tungsten wire without annealing, with lanthanum oxide content of 0.60%-0.80%, strength of 2300-2500 MPa, and wire diameter of 0.39 mm, is selected as the wire, and 10 shafts of tungsten wire without annealing are taken for A and B groups of experiments, respectively.

[0048] The A group experiment is a traditional tungsten wire drawing process, including the following steps:

[0049] a. annealing: the tungsten wire busbar with lanthanum oxide content of 0.60%-0.80%, strength of 2300-2500 MPa, and wire diameter of 0.39 mm is flame annealed at a temperature of 1600-1700℃ to obtain a tungsten wire busbar;

[0050] b. rough drawing: the annealed tungsten wire busbar is drawn to a tungsten wire with a wire diameter of 0.16-0.18 mm by using an electric heating large die drawing machine at a temperature of 800-850℃ and a reduction of 16%-22%;

[0051] c. medium drawing: the rough drawn tungsten wire is drawn to a tungsten wire with a wire diameter of 0.06-0.08 mm by using an electric heating medium die drawing machine at a temperature of 400-500℃ and a reduction of 16%-22%;

[0052] d. fine drawing: the medium drawn tungsten wire is drawn to a tungsten wire with a wire diameter of 0.028-0.03 mm by using an electric heating small die drawing machine at a temperature of 300-400℃ and a reduction of 16%-22%.

[0053] The B group experiment is a high-performance tungsten wire drawing process proposed by the present application, including the following steps:

[0054] S1, rough drawing: the tungsten wire busbar with lanthanum oxide content of 0.60%-0.80%, strength of 2300-2500 MPa, and wire diameter of 0.39 mm is drawn to a tungsten wire with a wire diameter of 0.16-0.18 mm by using a gas heating die drawing machine at a temperature of 900-950℃ and a reduction of 16%-22%;

[0055] S2, medium drawing: the rough drawn tungsten wire is drawn to a tungsten wire with a wire diameter of 0.06-0.08 mm by using an electric heating medium die drawing machine at a temperature of 400-500℃ and a reduction of 16%-22%;

[0056] S3, fine drawing: the medium drawn tungsten wire is drawn to a tungsten wire with a target wire diameter of 0.028-0.030 mm by using an electric heating small die drawing machine at a temperature of 300-400℃ and a reduction of 16%-22%.

[0057] Experiment one

[0058] In the A and B group experiments, the strength of the tungsten wire drawn to 0.16 mm from the tungsten wire busbar without annealing is detected, and the experimental data is shown in Table 1.

[0059] Table 1

[0060]

[0061] The first experiment is to compare the strength of tungsten wires after the rough drawing stage of groups A and B. According to the data in Table 1, the average strength of tungsten wires after the rough drawing stage is 180 MPa higher than that of the traditional drawing process, and the microstructure and mechanical properties of the tungsten wires are more excellent, which is beneficial to the subsequent drawing process.

[0062] The second experiment

[0063] On the basis of the first experiment, 100 meters of 0.16 mm tungsten wire from each of the 20 shafts are electrolytically etched with a reducing etching solution to gradually reduce the diameter of the tungsten wire. When the diameter reaches 0.15 mm, 0.13 mm, 0.11 mm, 0.08 mm and 0.04 mm, respectively, the corresponding strength is detected and recorded. The experimental data are shown in Table 2.

[0064] Table 2

[0065]

[0066] The second experiment is to detect the strength of each cross section of the tungsten wire and analyze the strength difference between the core and the surface of the tungsten wire. As can be seen from the data in Table 2, the strength of group A continuously decreases as the wire diameter decreases, with a decrease of 11.3%. In particular, the core strength plummets, with a strength of only 2963 MPa at a wire diameter of 0.04 mm, indicating that the traditional process refines the surface but coarsens the core. When drawing to a thin wire, the core becomes a weak area and is prone to breakage. The strength of group B fluctuates less with a fluctuation range of only 0.3%, and the strength at a wire diameter of 0.04 mm still remains at 3352 MPa, indicating that the drawing process of the present application has more uniform strength from the inside to the outside of the tungsten wire, has uniformity of the whole cross-sectional strength, and has higher overall strength, thereby improving the microstructure and mechanical properties of the tungsten wire.

[0067] The third experiment

[0068] On the basis of the first experiment, the 0.16 mm tungsten wire from the 20 shafts is further drawn to a tungsten wire with a wire diameter of 0.028 mm, and the strength of the tungsten wire is tested to obtain the experimental data shown in Table 3.

[0069] Table 3

[0070]

[0071] The third experiment is to detect the strength of the tungsten wire product of the drawing process. As can be seen from Table 3, the average strength of the tungsten wire product of the group A experiment is 6366 MPa, while the average strength of the tungsten wire product of the group B experiment is 6579 MPa, which is 213 MPa higher than that of group A. The strength of all products of group B is higher than 6500 MPa, and the drawing process of the present application has stability and excellent mechanical properties of the product.

[0072] The fourth experiment

[0073] On the basis of Experiment Three, the 20-axis 0.028mm finished tungsten wire is tested for breakage rate, and the experimental data are shown in Table 4.

[0074] Table 4

[0075]

[0076] Experiment Four is a further analysis of the finished breakage rate. As shown in the above table data, the breakage rate of Group A fluctuates greatly, and there is a significant difference between samples. The breakage rate of 60% of the samples is >5%, and the highest is 12.5%, reflecting that the quality of the traditional process is unstable and is affected by the random effects of unevenness of the organization (as shown in Table 2) and insufficient strength (as shown in Table 3). The breakage rate of Group B is 0% for 8 samples, and only 2 samples are non-zero (6.67%, 4.35%), and none exceeds 7%, reflecting that the drawing process provided by the present application has high reliability, and the advantages of uniformity of the organization and strength are converted into stable low breakage rate. Compared with the current breakage rate level (6%-10%) in the industry, the breakage rate of Group B is reduced by about 80%, and the average breakage rate of Group B is 1.28%, which meets the requirement of breakage rate ≤2% for photovoltaic cutting.

[0077] The present application solves the problems of uneven organization refinement, insufficient surface strength and high breakage rate in traditional tungsten wire drawing through the synergistic innovation of gas heating ten-die wire drawing machine and high-performance tungsten wire drawing process. The close combination of equipment and process, the high-precision temperature control provided by the gas heating ten-die wire drawing machine creates the basic conditions for dynamic recrystallization in the process, and the process cancels the high-temperature annealing step and directly uses the 900-950℃ rough drawing process to fully utilize the uniform heating characteristics of the equipment. Specifically, the 10 independent temperature control heating units of the equipment realize non-contact radiation heating of the wire through the PID closed-loop control system (including temperature measuring sensor, electrical proportional valve and electrical controller), ensuring the uniformity of the full cross-section temperature, and avoiding the core coarse grain problem caused by the traditional electric heating contact method; in terms of process, the first 900-950℃ dynamic recrystallization rough drawing step is directly implemented on the equipment, which utilizes the synchronous mechanism of deformation and recrystallization to promote the tungsten wire organization to be ultra-fined to 1.5μm, significantly improve the strength and reduce the breakage rate. The relevance of this equipment and process not only optimizes the microstructure of the tungsten wire, but also brings significant macro benefits: the strength of the finished tungsten wire ≥6500MPa, the breakage rate of photovoltaic cutting ≤2%, and the energy saving of 40% and the shortening of production cycle. Experimental data show that compared with the traditional process, the present application realizes a breakthrough in the uniformity of the full cross-section strength and the mechanical properties of the tungsten wire.

[0078] Those skilled in the art can make various modifications and variations to the above embodiments based on the disclosure and teachings of this specification. Therefore, the present application should not be limited to the above specific embodiments, and any obvious modifications, replacements or variations made by those skilled in the art based on the present application shall fall within the scope of the present application. In addition, although some specific terms are used in this specification, these terms are only for the convenience of description and do not constitute any limitation on the present application.

Claims

1. A high performance tungsten wire drawing process characterized by, The method comprises the following steps: S1, rough drawing: drawing a tungsten wire with a lanthanum oxide content of 0.60%-0.80%, a strength of 2300-2500 MPa, and a wire diameter of 0.39 mm to a wire diameter of 0.16-0.18 mm at a temperature of 900-950 DEG C without annealing; S2, medium drawing: drawing the rough-drawn tungsten wire at 400-500 DEG C to a wire diameter of 0.06-0.08 mm; S3, fine drawing: drawing the medium-drawn tungsten wire at 300-400 DEG C to a target wire diameter of 0.028-0.030 mm; The high-performance tungsten wire drawing process is implemented by using a gas-heated ten-die wire drawing machine, which comprises a machine frame (1) and an electrical controller (2), and is provided with a magnetic damping pay-off reel (3), a guide wheel (4), a natural gas furnace (5), a drawing die frame (6), a capstan (7) and a servo wire collecting reel (8) in sequence along a wire processing path on the machine frame (1); the natural gas furnace (5) comprises ten heating units (51) capable of being independently controlled in temperature; an electrical proportional valve (52) is further arranged on the machine frame (1), which is used for adjusting the mixing ratio of natural gas and compressed air in the heating units (51) and is signal connected with the electrical controller (2); a temperature measuring sensor (53) is further arranged above the heating units (51), which is signal connected with the electrical controller (2) and is used for monitoring the wire temperature in real time and feeding back to the electrical controller (2), and the electrical controller (2) dynamically controls the electrical proportional valve (52) based on a PID algorithm, so that the wire temperature in the heating units (51) is maintained within a range of the set value ± 5 DEG C.

2. A high performance tungsten wire drawing process as claimed in claim 1, wherein, The tungsten wire obtained in step S3 has a strength of greater than or equal to 6500 MPa, and a photovoltaic cutting wire breakage rate of less than or equal to 2%.

3. A high performance tungsten wire drawing process as claimed in claim 1, wherein, A jitter-stabilizing assembly (9) is arranged between the magnetic damping pay-off reel (3) and the guide wheel (4), which comprises a support arm (91), a fixed pulley (92) and a floating pulley (93), the support arm (91) is fixedly connected to the machine frame (1), the fixed pulley (92) is detachably connected to one end of the support arm (91) close to the guide wheel (4), a vertical guide rail (94) is arranged on the support arm (91), and the floating pulley (93) is slidingly connected to the vertical guide rail (94), and the wire is arranged in an "S" shape or a "Z" shape around the fixed pulley (92) and the floating pulley (93).

4. A high performance tungsten wire drawing process as claimed in claim 1, wherein, A graphite emulsion coating box (10) is arranged between the guide wheel (4) and the natural gas furnace (5), a plurality of through lubricating grooves (101) are arranged in the graphite emulsion coating box (10), and the through lubricating grooves (101) are used for passing the wire.

5. A high performance tungsten wire drawing process as claimed in claim 1, wherein, The adjustable support (54) is arranged on the rack (1), and comprises a fixed plate (541) and a rotating frame (542), the temperature measuring sensor (53) is fixedly connected to the rotating frame (542), and the side wall of the rotating frame (542) is rotatably connected to the fixed plate (541); the fixed plate (541) is provided with an arc-shaped limiting hole (543), and the arc-shaped limiting hole (543) is used for restricting the rotation angle of the rotating frame (542).

6. A high performance tungsten wire drawing process as claimed in claim 1, wherein, The rack (1) is provided with a translation guide rail (11), the sliding direction of the translation guide rail (11) is perpendicular to the wire processing path, and the translation guide rail (11) is used for driving the servo wire collecting disc (8) to reciprocatingly slide.

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