A pulse current uniform loading device and method based on gradient temperature field modulation

Abstract

This invention relates to the field of metal material rolling forming technology, and discloses a pulse current uniform loading device and method based on gradient temperature field modulation. The device includes a reversible winding and unwinding mechanism, a reversible rolling mill, an electrical treatment mechanism, and a pulse power supply system. The reversible winding and unwinding mechanism is used to transport the strip; the reversible rolling mill is used to roll the strip; the electrical treatment mechanism is provided in two sets, symmetrically arranged on both sides of the reversible rolling mill; the electrical treatment mechanism includes an electromagnetic gradient heating component, a conductive roller component, and a heat preservation and cooling component. The electromagnetic gradient heating component is used to apply a gradient temperature along the width direction of the strip, and is positioned close to the reversible rolling mill. This invention can construct a preset gradient temperature distribution along the width direction of the strip, achieving uniform pulse current loading along the width direction of the strip, significantly improving the consistency of the pulse current-assisted rolling effect, suppressing uneven current distribution from a physical source, and improving rolling quality.

Description

Technical Field

[0001] This invention relates to the field of metal material rolling forming technology, and in particular to a pulse current uniform loading device and method based on gradient temperature field modulation. Background Technology

[0002] In existing pulsed current-assisted rolling of wide-width (typically referring to width > 600 mm) ultra-thin strips, the current exhibits a severely uneven distribution along the strip width due to the "edge effect." Specifically, the current density is significantly higher at the edges of the strip and lower in the core. This uneven current distribution directly leads to uneven rolling deformation, large gradients in microstructure and properties, and complex residual stress, severely affecting product yield and service reliability.

[0003] Existing technologies mainly alleviate this problem by optimizing electrode contact, segmenting electrodes, or improving current waveforms. However, most solutions still "compensate for current distribution at the result end" and do not fundamentally change the natural attenuation law of current caused by uneven distribution of the material's own physical properties (conductivity, permeability). The effects are limited and the control is complex, especially in the case of wide-range, ultra-thin, and reciprocating multi-pass operation.

[0004] To address this, a pulse current uniform loading device and method based on gradient temperature field modulation is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a pulse current uniform loading device and method based on gradient temperature field modulation, which aims to solve or improve at least one of the above-mentioned technical problems.

[0006] To achieve the above objectives, the present invention provides the following solution: The present invention provides a pulse current uniform loading device based on gradient temperature field modulation, comprising: A reversible winding and unwinding mechanism is used to convey strip material; A reversible rolling mill, the reversible rolling mill being used to roll the strip; The electrical treatment mechanism comprises two sets, which are symmetrically arranged on both sides of the reversible rolling mill. The electrical treatment mechanism includes an electromagnetic gradient heating component, a conductive roller component, and a heat preservation and cooling component. The electromagnetic gradient heating component is used to apply a gradient temperature along the width direction of the strip, and the electromagnetic gradient heating component is arranged close to the reversible rolling mill. The pulse power supply system is electrically connected to both the work roll group of the reversible rolling mill and the conductive roll assembly.

[0007] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein the electrical processing mechanism further includes a temperature potential monitoring feedback component. The temperature potential monitoring feedback component includes a control system, a temperature sensor array, and a potential monitoring sensor array. The temperature sensor array and the potential monitoring sensor array are both arranged along the width direction of the strip, and are both located close to the electromagnetic gradient heating component. The electromagnetic gradient heating component, the temperature sensor array, and the potential monitoring sensor array are all electrically connected to the control system.

[0008] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein the electromagnetic gradient heating component includes an upper excitation coil array and a lower excitation coil array, the upper excitation coil array being located above the strip and the lower excitation coil array being located below the strip; The upper excitation coil array and the lower excitation coil array are provided with a preset misalignment along the width direction of the strip; Electromagnetic shields are installed on the side of the upper excitation coil array and the lower excitation coil array away from the strip; both the upper excitation coil array and the lower excitation coil array are electrically connected to the control system; the temperature sensor array and the potential monitoring sensor array are installed on one side of the upper excitation coil array and the lower excitation coil array respectively.

[0009] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein the electrical processing mechanism further includes an upper housing cover and a lower housing cover; the upper housing cover and the lower housing cover are fixedly connected by bolts, and the upper housing cover and the lower housing cover together form a closed cavity, and a material passage port is opened on both sides of the closed cavity, the material passage port being used to convey the strip material; The enclosed cavity contains an electromagnetic heating chamber, a heat preservation chamber, and a cooling chamber arranged in sequence. The electromagnetic shield, the temperature sensor array, and the potential monitoring sensor array are all located in the electromagnetic heating chamber. The heat preservation and cooling assembly includes a heat preservation component and a cooling tensioning component. The heat preservation component is located in the heat preservation chamber, and the cooling tensioning component is located in the cooling chamber. The conductive roller assembly is located between the cooling tensioning component and the heat preservation component.

[0010] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein the heat preservation component includes an upper heat preservation plate and a lower heat preservation plate, and both the upper heat preservation plate and the lower heat preservation plate are installed in the heat preservation chamber; The cooling tensioning component includes a one-way gas circulation system, a moving roller, and two tensioning rollers; the one-way gas circulation system includes an exhaust fan, a plate-fin heat exchanger, and a cooling fan connected in sequence by pipelines. The exhaust fan, the plate-fin heat exchanger, and the cooling fan are all installed on the upper housing cover. The working end of the exhaust fan is connected to the insulation chamber, the exhaust end of the cooling fan is connected to the cooling chamber, and the plate-fin heat exchanger is connected to an inert gas source for introducing inert gas into the closed cavity. The two tensioning rollers are installed side by side at intervals on the inner wall of the cooling chamber. The moving roller is installed on the inner wall of the cooling chamber via a servo electric cylinder. The moving roller is located between the two tensioning rollers. The strip is wound around the moving roller and the two tensioning rollers. The servo electric cylinder, the air extractor, and the cooling fan are all electrically connected to the control system. The conductive roller assembly includes an upper conductive roller and a lower conductive roller arranged opposite to each other. The upper conductive roller is installed on the inner wall of the upper housing cover, and the lower conductive roller is installed on the inner wall of the lower housing cover. The upper conductive roller and the upper insulation plate are both located above the strip, and the lower conductive roller and the lower insulation plate are both located below the strip. The upper conductive roller and the lower conductive roller are both in contact with the strip, and the upper conductive roller and the lower conductive roller are both electrically connected to the pulse power supply system.

[0011] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein the upper excitation coil array and the lower excitation coil array have the same structure; The upper excitation coil array includes a plurality of excitation coils arranged along the width direction of the strip. The electromagnetic shield covers the side of the plurality of excitation coils away from the strip. The excitation coils are wound with hollow copper tubes. An iron yoke is provided inside the excitation coils. Coolant flows inside the hollow copper tubes. The plurality of excitation coils are electrically connected to the control system.

[0012] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein the control system adopts an industrial PLC or an industrial control computer.

[0013] According to the present invention, a pulse current uniform loading device based on gradient temperature field modulation is provided, wherein a ceramic intermediate roll is installed on the side of the working roll group of the reversible rolling mill away from the strip, and the reversible rolling mill is a reversible twenty-roll rolling mill.

[0014] The present invention also provides a method for uniformly loading pulsed current based on gradient temperature field modulation, comprising the following steps: Step 1: Roll the strip in a reversible rolling mill in either the forward or reverse direction; Step 2: Activate the electrical treatment mechanism on the corresponding side according to the rolling direction of the strip, and form a preset gradient temperature distribution in the width direction of the strip through the electromagnetic gradient heating component; Step 3: A current loop is formed by the working roll group and the conductive roll assembly of the reversible rolling mill to apply a pulse current to the strip, so that the pulse current acts continuously and synchronously in the rolling deformation zone and the post-rolling running zone. Step 4: Collect the temperature distribution and electrical parameters in the width direction of the strip, and perform closed-loop correction on the zoned heating parameters and / or pulse current parameters of the electromagnetic gradient heating component; Step 5: Switch the rolling direction and repeat steps 2 to 4.

[0015] According to the present invention, a pulse current uniform loading method based on gradient temperature field modulation is provided, wherein the heating temperature of the strip does not exceed one-third of the recrystallization temperature of the strip.

[0016] The present invention discloses the following technical effects: This invention employs a front-end active modulation of the material's intrinsic properties and a rear-end natural guidance of uniform current. When the strip enters the current loading zone (rolling deformation zone), a non-uniform gradient temperature field with a specific distribution is applied along the strip's width. Since the resistivity of metallic materials is a function of temperature (usually a positive temperature coefficient), the gradient temperature field will correspondingly form a gradient resistivity field. Based on the physical law that current naturally tends to flow to low-resistance paths, by adjusting the gradient temperature field distribution along the strip's width using an electromagnetic gradient heating component, a resistivity "groove" or "channel" can be actively created, thereby modulating the uniform distribution of the equivalent resistance along the strip's width. This achieves uniform loading of the pulsed current along the strip's width, suppressing uneven current distribution from a physical source and improving rolling quality. This invention uses an electromagnetic gradient heating component to apply a gradient temperature along the width direction of the strip, constructing a preset gradient temperature distribution along the width direction of the strip. By using "temperature-resistance" coupling to modulate the equivalent resistance distribution along the width direction, it achieves uniform pulse current loading along the width direction of the strip, significantly improving the consistency of pulse current-assisted rolling effect, significantly reducing the risk of edge current segregation and overheating; it also reduces the dependence on complex partitioned electrodes or high-precision contact devices, improves system reliability, and reduces maintenance costs. This invention is designed for multi-pass reciprocating rolling production lines for ultra-thin strips. It features symmetrically arranged electrical treatment mechanisms on both sides, coordinated with electrode switching, to achieve online electrical treatment between passes, thereby improving production cycle time and continuity. The electromagnetic gradient heating component can be adaptively set according to a preset temperature distribution direction and amplitude, and has strong material versatility. The gradient preheating of this invention helps to reduce the material's deformation resistance and produces a synergistic effect with the electroplastic effect of pulsed current, further reducing rolling force and energy consumption. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the electrical processing mechanism in this invention; Figure 3 This is a schematic diagram of the internal structure of the electrical processing mechanism in this invention; Figure 4 This is a schematic diagram of the electromagnetic gradient heating component in this invention; Figure 5 This is a schematic diagram of the staggered arrangement of the upper excitation coil array and the lower excitation coil array in this invention; Figure 6 This is a schematic diagram illustrating the forward rolling process of the present invention; Figure 7 This is a schematic diagram of the reverse rolling process of the present invention.

[0019] The components include: 1. Reversible winding and unwinding mechanism; 2. Strip material; 3. Reversible 20-roll mill; 31. Work roll group; 32. Ceramic intermediate roll; 4. Electrostatic treatment mechanism; 411. Upper housing cover; 412. Electromagnetic gradient heating assembly; 4121. Upper excitation coil array; 4122. Electromagnetic shield; 4123. Temperature sensor array; 4124. Potential monitoring sensor array; 413. Upper insulation plate; 414. Upper conductive roll; 415. Air extraction fan; 416. Plate-fin heat exchanger; 417. Cooling fan; 421. Lower housing cover; 4221. Lower excitation coil array; 423. Lower insulation plate; 424. Lower conductive roll; 425. Tensioning roll; 426. Moving roll; 427. Servo electric cylinder. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Reference Figures 1-7 This invention provides a pulse current uniform loading device based on gradient temperature field modulation, comprising: The reversible winding and unwinding mechanism 1 is used to convey the strip 2. The reversible winding and unwinding mechanism 1 includes two winding and unwinding devices, which are located on both sides of the reversible rolling mill and two sets of electrical treatment mechanisms 4, respectively, to realize the forward or reverse conveying of the strip 2. Reversible rolling mill, used for rolling strip 2; The electrical treatment mechanism 4 is provided in two sets, and the two sets of electrical treatment mechanisms 4 are symmetrically arranged on both sides of the reversible rolling mill. The electrical treatment mechanism 4 includes an electromagnetic gradient heating assembly 412, a conductive roll assembly and a heat preservation and cooling assembly. The electromagnetic gradient heating assembly 412 is used to apply gradient temperature along the width direction of the strip 2. The electromagnetic gradient heating assembly 412 is close to the reversible roll and is set in the rolling mill. The pulse power supply system connects the work roll group 31 and the conductive roll assembly of the reversible rolling mill to the pulse power supply system. With this configuration, the present invention adopts a mode of actively modulating the intrinsic properties of the material at the front end and naturally guiding the uniformity of the current at the back end. When the strip 2 enters the current loading zone (rolling deformation zone), a non-uniform gradient temperature field with a specific distribution is applied in the width direction of the strip 2. Since the resistivity of the metallic material is a function of temperature (usually a positive temperature coefficient), the gradient temperature field will correspondingly form a gradient resistivity field. According to the physical law that the current will naturally tend to flow to the low resistance path, by adjusting the gradient temperature field distribution in the width direction of the strip 2 through the electromagnetic gradient heating component 412 (for example, making the temperature in the width direction of the strip 2 gradually increase from the center to the edge), a resistivity "groove" or "channel" can be actively created, thereby modulating the uniform distribution of the equivalent resistance in the width direction of the strip, realizing the uniform loading of the pulse current in the width direction of the strip 2, suppressing the uneven current distribution from the physical source, and improving the rolling quality. This invention uses an electromagnetic gradient heating component 412 to apply a gradient temperature along the width direction of the strip 2, constructing a preset gradient temperature distribution along the width direction of the strip 2. By using "temperature-resistance" coupling to modulate the equivalent resistance distribution along the width direction, it achieves uniform pulse current loading along the width direction of the strip 2, significantly improving the consistency of the pulse current-assisted rolling effect, significantly reducing the risk of edge current segregation and overheating; it also reduces the dependence on complex partitioned electrodes or high-precision contact devices, improves system reliability, and reduces maintenance costs. This invention is designed for multi-pass reciprocating rolling production lines for ultra-thin strips. The electrical treatment mechanism 4 is symmetrically arranged on both sides and works in conjunction with electrode switching to achieve online electrical treatment between passes, thereby improving production cycle time and continuity. The electromagnetic gradient heating component 412 can be adaptively set according to the preset temperature distribution direction and amplitude, and has strong material versatility. The gradient preheating of this invention helps to reduce the material's deformation resistance and produces a synergistic effect with the electroplastic effect of pulsed current, further reducing rolling force and energy consumption.

[0023] In a further optimized scheme, the electrical processing mechanism 4 also includes a temperature and potential monitoring feedback component. The temperature and potential monitoring feedback component includes a control system, a temperature sensor array 4123, and a potential monitoring sensor array 4124. Both the temperature sensor array 4123 and the potential monitoring sensor array 4124 are arranged along the width direction of the strip 2, and both the temperature sensor array 4123 and the potential monitoring sensor array 4124 are located close to the electromagnetic gradient heating component 412. The electromagnetic gradient heating component 412, the temperature sensor array 4123, and the potential monitoring sensor array 4124 are all electrically connected to the control system. During operation, after the electromagnetic gradient heating component 412 applies a gradient temperature to the strip 2, the temperature sensor array 4123 simultaneously collects the actual temperature data at various points along the width direction of the strip 2, and the potential monitoring sensor array 4124 collects the potential distribution data at various points along the width direction of the strip 2. Both sets of data are transmitted to the control system in real time. The control system controls the heating parameters of the electromagnetic gradient heating component 412 based on the actual temperature and potential data, adjusts the gradient temperature field distribution along the width direction of the strip 2, thereby optimizing the gradient resistivity field and guiding the uniform loading of the pulse current. This achieves closed-loop control of "heating-monitoring-feedback-correction," significantly improving the consistency and reliability of the pulse current loading.

[0024] Further optimization of the scheme: the electromagnetic gradient heating assembly 412 includes an upper excitation coil array 4121 and a lower excitation coil array 4221. The upper excitation coil array 4121 is located above the strip 2, and the lower excitation coil array 4221 is located below the strip 2. The upper excitation coil array 4121 and the lower excitation coil array 4221 are set with a preset misalignment along the width direction of the strip 2; Electromagnetic shielding cover 4122 is installed on the side of the upper excitation coil array 4121 and the lower excitation coil array 4221 away from the strip 2; both the upper excitation coil array 4121 and the lower excitation coil array 4221 are electrically connected to the control system; a temperature sensor array 4123 and a potential monitoring sensor array 4124 are installed on one side of the upper excitation coil array 4121 and the lower excitation coil array 4221, respectively. During operation, the control system outputs control currents of different amplitudes to the upper excitation coil array 4121 and the lower excitation coil array 4221 according to the preset gradient temperature distribution requirements. Using the principle of electromagnetic induction, the two coil arrays generate gradient-distributed induced magnetic fields, which act on the upper and lower surfaces of the strip 2 to achieve gradient heating in the width direction of the strip 2.

[0025] The staggered arrangement can reduce the transverse sawtooth temperature fluctuations caused by uneven magnetic field at the coil ends.

[0026] The electromagnetic shield 4122 can concentrate and confine the magnetic field generated by the coil array in the heating area of ​​the strip 2, reduce the interference of magnetic field leakage to surrounding components, and reduce energy loss. The temperature sensor array 4123 and potential monitoring sensor array 4124 on both sides can collect data after heating in real time, providing accurate basis for closed-loop correction of the control system and further optimizing the gradient temperature field modulation effect.

[0027] In a further optimized scheme, the electrical treatment mechanism 4 also includes an upper housing cover 411 and a lower housing cover 421; the upper housing cover 411 and the lower housing cover 421 are fixed together by bolts, and the upper housing cover 411 and the lower housing cover 421 together form a closed cavity, and material passage ports are opened on both sides of the closed cavity for conveying the belt material 2. The enclosed cavity contains an electromagnetic heating chamber, a heat preservation chamber, and a cooling chamber arranged in sequence. The electromagnetic shield 4122, the temperature sensor array 4123, and the potential monitoring sensor array 4124 are all located in the electromagnetic heating chamber. The heat preservation and cooling assembly includes a heat preservation component and a cooling tensioning component. The heat preservation component is located in the heat preservation chamber, and the cooling tensioning component is located in the cooling chamber. The conductive roller assembly is located between the cooling tensioning component and the heat preservation component. During operation, strip 2 enters the enclosed cavity through the feed port, sequentially passing through the electromagnetic heating chamber, the insulation chamber, and the cooling chamber, achieving continuous and coordinated "heating-insulation-cooling" processing. The upper excitation coil array 4121, lower excitation coil array 4221, electromagnetic shield 4122, temperature sensor array 4123, and potential monitoring sensor array 4124 within the electromagnetic heating chamber work together to complete the gradient heating and data acquisition of strip 2. The enclosed environment reduces heat loss and ensures a stable temperature field. The insulation components in the insulation chamber can maintain the gradient temperature of strip 2, preventing the temperature of strip 2 from dropping rapidly before entering the cooling chamber, and preventing the fluctuation of resistivity field from affecting the uniform loading of current; the cooling tensioning components in the cooling chamber can moderately cool strip 2, so that the temperature of strip 2 drops to a range suitable for subsequent rolling, while maintaining the tension of strip 2, preventing strip 2 from shifting and affecting current loading and rolling accuracy.

[0028] The detachable connection design of the upper housing cover 411 and the lower housing cover 421 facilitates the installation, debugging and maintenance of internal components. The sealed cavity can also prevent external dust and debris from entering, thus improving the stability of equipment operation.

[0029] The design is further optimized. The insulation components include an upper insulation plate 413 and a lower insulation plate 423, both of which are installed in the insulation chamber. The cooling tensioning component includes a one-way gas circulation system, a moving roller 426, and two tensioning rollers 425. The one-way gas circulation system includes an exhaust fan 415, a plate-fin heat exchanger 416, and a cooling fan 417 connected in sequence by pipelines. The exhaust fan 415, the plate-fin heat exchanger 416, and the cooling fan 417 are all installed on the upper housing cover 411. The working end of the exhaust fan 415 is connected to the insulation chamber, the exhaust end of the cooling fan 417 is connected to the cooling chamber, and the plate-fin heat exchanger 416 is connected to an inert gas source for introducing inert gas into the closed cavity. Two tensioning rollers 425 are installed side-by-side at intervals on the inner wall of the cooling chamber. A moving roller 426 is installed on the inner wall of the cooling chamber via a servo electric cylinder 427. The moving roller 426 is located between the two tensioning rollers 425. The strip 2 is wound around the moving roller 426 and the two tensioning rollers 425. The servo electric cylinder 427, the vacuum pump 415, and the cooling fan 417 are all electrically connected to the control system. Through unidirectional circulating gas heat exchange and inert gas supply, energy efficiency is improved and the risk of oxidation in the high-temperature zone is reduced. During operation, the servo electric cylinder 427 drives the moving roller 426 to move up and down, cooperating with the two tensioning rollers 425 to adjust the tension of the strip 2. The strip 2 forms an S-shaped path around the three rollers. Combined with the feedback from the tension detection component, closed-loop adjustment is performed to stabilize the running tension of the strip and improve the running stability of the ultra-thin strip, ensuring that the strip 2 is flat and without deviation, and avoiding poor contact between the strip 2 and the conductive roller assembly, which would affect the current loading. At the same time, the unidirectional gas circulation system is started, and the air extractor 415 extracts the hot air from the insulation chamber and cooling chamber and sends it to the plate-fin heat exchanger 416 for cooling. The cooled gas is sent into the cooling chamber by the cooling fan 417 to air-cool the strip 2, realizing heat recycling and improving energy efficiency; the plate-fin heat exchanger 416 is connected to the inert gas source and introduces inert gas into the closed cavity, which can reduce the risk of oxidation of the strip 2 at high temperature and protect the surface quality of the strip 2; the control system can adjust the speed of the vacuum fan 415 and the cooling fan 417 and the extension and retraction of the servo electric cylinder 427 according to the temperature data of the strip 2, so as to precisely control the cooling speed and the tension of the strip 2 and adapt to the processing requirements of strips 2 of different specifications.

[0030] The conductive roller assembly includes an upper conductive roller 414 and a lower conductive roller 424 arranged opposite to each other. The upper conductive roller 414 is installed on the inner wall of the upper housing cover 411, and the lower conductive roller 424 is installed on the inner wall of the lower housing cover 421. The upper conductive roller 414 and the upper insulation plate 413 are both located above the strip 2, and the lower conductive roller 424 and the lower insulation plate 423 are both located below the strip 2. The upper conductive roller 414 and the lower conductive roller 424 are both in contact with the strip 2, and the upper conductive roller 414 and the lower conductive roller 424 are both electrically connected to the pulse power supply system. The upper conductive roller 414 and the lower conductive roller 424 are electrically connected and at the same potential, serving as return electrode nodes, so that the current of the strip 2 flows out in parallel at the upper and lower contact interfaces and converges back to the pulse power supply system.

[0031] To suppress bypassing of the housing, insulating isolation structures such as insulating bearings, insulating bushings, or insulating gaskets are preferably provided between the upper conductive roller 414 and the lower conductive roller 424 and the upper housing cover 411 and the lower housing cover 421. The roller surfaces of the upper conductive roller 414 and the lower conductive roller 424 are provided with conductive wear-resistant coatings, replaceable conductive sleeves, or micro-textured structures to reduce contact resistance fluctuations and suppress local hot spots.

[0032] The scheme is further optimized so that the upper excitation coil array 4121 and the lower excitation coil array 4221 have the same structure; The upper excitation coil array 4121 includes several excitation coils arranged along the width direction of the strip 2. An electromagnetic shield 4122 covers the side of the several excitation coils away from the strip 2. The excitation coils are wound with hollow copper tubes and have iron yokes inside. Coolant flows inside the hollow copper tubes. The several excitation coils are electrically connected to the control system.

[0033] Coolant is circulated inside the hollow copper tube for forced cooling to meet the thermal stability and lifespan requirements of the coil under continuous production conditions.

[0034] Further optimization of the scheme: the control system adopts an industrial PLC or industrial control computer; during forward rolling, the strip 2 is unwound and wound by two winding and unwinding devices of the reversible winding and unwinding mechanism 1 respectively. The strip 2 passes through the electrical treatment mechanism 4 near the unwinding side but is not energized. After entering the reversible twenty-roll mill 3 to complete rolling, it enters another electrical treatment mechanism 4. In this electrical treatment mechanism 4, the energized rolling circuit is closed and the pulse current is uniformly loaded under the modulation of the gradient temperature field.

[0035] In reverse rolling, the process is reversed, and only the electrical processing mechanism 4, which is far from the unwinding side, is activated.

[0036] To ensure production safety and avoid bypass diversion, the control system is equipped with interlocking logic, which allows only the electrical processing mechanism 4 on the side corresponding to the rolling direction to be energized at any given time.

[0037] Further optimization of the scheme: a ceramic intermediate roll 32 is installed on the side of the reversible roll mill's work roll group 31 away from the strip 2; the reversible roll mill adopts a reversible twenty-roll mill 3. The reversible 20-roll mill 3 has the advantages of high rolling precision, uniform rolling force, and bidirectional reciprocating rolling. It can accurately control the rolling thickness and flatness of the strip 2 and is suitable for the high-precision rolling requirements of ultra-thin strips. The two ends of the work roll group 31 of the reversible 20-roll mill are electrically connected to the pulse power supply component through brushes, so that the work roll group 31 inputs pulse current to the strip 2 in the rolling contact area. The intermediate roll that contacts the work roll group 31 is a ceramic intermediate roll 32 to achieve electrical isolation of the work roll group 31, suppress the current to bypass the stand or other roll system, so that the pulse current is mainly closed through the path of "work roll group 31-strip 2-corresponding side conductive roll".

[0038] In addition, the ceramic intermediate roll 32 can improve the stability of the work roll group 31, reduce the wear of the work roll group 31, extend the service life of the rolling mill, and, together with the reciprocating rolling function of the reversible twenty-roll mill 3, realize the coordinated operation of multi-pass online electrical treatment and rolling, further improving the rolling quality of ultra-thin strip.

[0039] The scheme was further optimized by arranging the electromagnetic heating chamber close to the exit side of the work roll group 31 of the reversible 20-roll mill 3 to reduce the time delay in the construction of the temperature field after the strip leaves the rolling zone.

[0040] This invention also provides a method for uniformly loading pulsed current based on gradient temperature field modulation, comprising the following steps: Step 1: Roll strip 2 in a reversible rolling mill in either the forward or reverse direction; Step 2: Activate the electrical treatment mechanism 4 on the corresponding side according to the rolling direction of strip 2, and form a preset gradient temperature distribution in the width direction of strip 2 through the electromagnetic gradient heating component 412; the preset gradient temperature distribution is used to modulate the equivalent resistance distribution in the width direction of strip 2, so that the pulse current tends to be uniformly loaded in the width direction of strip 2. Step 3: The working roll group 31 of the reversible rolling mill and the conductive roll assembly form a current loop to apply a pulse current to the strip 2, so that the pulse current acts continuously and synchronously in the rolling deformation zone and the post-rolling running zone. Step 4: Collect the temperature distribution and electrical parameters in the width direction of strip 2, and perform closed-loop correction on the zoned heating parameters and / or pulse current parameters of the electromagnetic gradient heating component 412; Step 5: Switch the rolling direction and repeat steps 2 to 4.

[0041] The scheme is further optimized so that the heating temperature of strip 2 does not exceed one-third of the recrystallization temperature of strip 2. This achieves equivalent resistance modulation without introducing significant microstructure recrystallization. The control system can adaptively correct the target temperature distribution based on online detection and process database, avoiding defects such as deformation and cracking of strip 2 after rolling. At the same time, this temperature range can synergize with the electroplastic effect of pulsed current, effectively reducing the deformation resistance of strip 2, reducing rolling force and energy consumption, balancing the uniform current loading effect and the material stability of strip 2, adapting to the rolling requirements of high-precision ultra-thin strips, and is especially suitable for strip 2 processing scenarios with high material performance requirements.

[0042] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0043] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A pulse current uniform loading device based on gradient temperature field modulation, characterized in that, include: A reversible winding and unwinding mechanism (1) is used to convey the strip (2). A reversible rolling mill, the reversible rolling mill being used to roll the strip (2); The electrical treatment mechanism (4) is provided in two sets, and the two sets of electrical treatment mechanisms (4) are symmetrically arranged on both sides of the reversible rolling mill; the electrical treatment mechanism (4) includes an electromagnetic gradient heating component (412), a conductive roller component and a heat preservation and cooling component, the electromagnetic gradient heating component (412) is used to apply gradient temperature along the width direction of the strip (2), and the electromagnetic gradient heating component (412) is arranged close to the reversible rolling mill; The pulse power supply system is electrically connected to the working roll group (31) of the reversible rolling mill and the conductive roll assembly.

2. The pulse current uniform loading device based on gradient temperature field modulation according to claim 1, characterized in that: The electrical processing mechanism (4) further includes a temperature potential monitoring feedback component, which includes a control system, a temperature sensor array (4123), and a potential monitoring sensor array (4124). The temperature sensor array (4123) and the potential monitoring sensor array (4124) are arranged along the width direction of the strip (2), and the temperature sensor array (4123) and the potential monitoring sensor array (4124) are both located close to the electromagnetic gradient heating component (412). The electromagnetic gradient heating component (412), the temperature sensor array (4123), and the potential monitoring sensor array (4124) are all electrically connected to the control system.

3. The pulse current uniform loading device based on gradient temperature field modulation according to claim 2, characterized in that: The electromagnetic gradient heating assembly (412) includes an upper excitation coil array (4121) and a lower excitation coil array (4221), the upper excitation coil array (4121) being located above the strip (2) and the lower excitation coil array (4221) being located below the strip (2); The upper excitation coil array (4121) and the lower excitation coil array (4221) are provided with a preset misalignment along the width direction of the strip (2); Electromagnetic shields (4122) are installed on the side of the upper excitation coil array (4121) and the lower excitation coil array (4221) away from the strip (2); the upper excitation coil array (4121) and the lower excitation coil array (4221) are both electrically connected to the control system; the temperature sensor array (4123) and the potential monitoring sensor array (4124) are installed on one side of the upper excitation coil array (4121) and the lower excitation coil array (4221).

4. The pulse current uniform loading device based on gradient temperature field modulation according to claim 3, characterized in that: The electrical processing mechanism (4) further includes an upper housing cover (411) and a lower housing cover (421); the upper housing cover (411) and the lower housing cover (421) are fixed together by bolts, and the upper housing cover (411) and the lower housing cover (421) together form a closed cavity, and material passage ports are opened on both sides of the closed cavity, which are used to convey the strip material (2). The enclosed cavity is provided with an electromagnetic heating chamber, a heat preservation chamber and a cooling chamber arranged in sequence. The electromagnetic shield (4122), the temperature sensor array (4123) and the potential monitoring sensor array (4124) are all located in the electromagnetic heating chamber. The heat preservation and cooling assembly includes a heat preservation component and a cooling tensioning component. The heat preservation component is located in the heat preservation chamber and the cooling tensioning component is located in the cooling chamber. The conductive roller assembly is located between the cooling tensioning component and the heat preservation component.

5. The pulse current uniform loading device based on gradient temperature field modulation according to claim 4, characterized in that: The insulation component includes an upper insulation plate (413) and a lower insulation plate (423), both of which are installed in the insulation cavity; The cooling tensioning component includes a one-way gas circulation system, a moving roller (426), and two tensioning rollers (425); the one-way gas circulation system includes an exhaust fan (415), a plate-fin heat exchanger (416), and a cooling fan (417) connected in sequence by pipelines. The exhaust fan (415), the plate-fin heat exchanger (416), and the cooling fan (417) are all installed on the upper housing cover (411). The working end of the exhaust fan (415) is connected to the heat preservation chamber, the exhaust end of the cooling fan (417) is connected to the cooling chamber, and the plate-fin heat exchanger (416) is connected to an inert gas source for introducing inert gas into the closed cavity. Two tensioning rollers (425) are installed side-by-side at intervals on the inner wall of the cooling chamber. The moving roller (426) is installed on the inner wall of the cooling chamber via a servo electric cylinder (427). The moving roller (426) is located between the two tensioning rollers (425). The strip (2) is wound around the moving roller (426) and the two tensioning rollers (425). The servo electric cylinder (427), the air extractor (415), and the cooling fan (417) are all electrically connected to the control system. The conductive roller assembly includes an upper conductive roller (414) and a lower conductive roller (424) arranged opposite to each other. The upper conductive roller (414) is installed on the inner wall of the upper housing cover (411), and the lower conductive roller (424) is installed on the inner wall of the lower housing cover (421). The upper conductive roller (414) and the upper insulation plate (413) are both located above the strip (2), and the lower conductive roller (424) and the lower insulation plate (423) are both located below the strip (2). The upper conductive roller (414) and the lower conductive roller (424) are both in contact with the strip (2), and the upper conductive roller (414) and the lower conductive roller (424) are both electrically connected to the pulse power supply system.

6. The pulse current uniform loading device based on gradient temperature field modulation according to claim 3, characterized in that: The upper excitation coil array (4121) and the lower excitation coil array (4221) have the same structure; The upper excitation coil array (4121) includes a plurality of excitation coils arranged along the width direction of the strip (2). The electromagnetic shield (4122) covers the side of the plurality of excitation coils away from the strip (2). The excitation coils are wound with hollow copper tubes. An iron yoke is provided inside the excitation coils. Cooling liquid flows inside the hollow copper tubes. The plurality of excitation coils are electrically connected to the control system.

7. The pulse current uniform loading device based on gradient temperature field modulation according to claim 2, characterized in that: The control system uses an industrial PLC or industrial computer.

8. The pulse current uniform loading device based on gradient temperature field modulation according to claim 1, characterized in that: The reversible rolling mill has a ceramic intermediate roll (32) installed on the side of the working roll group (31) away from the strip (2), and the reversible rolling mill is a reversible twenty-roll mill (3).

9. A method for uniformly loading pulse current based on gradient temperature field modulation, comprising the uniformly loading pulse current based on gradient temperature field modulation according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Roll the strip (2) in a reversible rolling mill in either the forward or reverse direction; Step 2: Start the electrical treatment mechanism (4) on the corresponding side according to the rolling direction of the strip (2), and form a preset gradient temperature distribution in the width direction of the strip (2) through the electromagnetic gradient heating assembly (412); Step 3: By forming a current loop with the working roll group (31) and the conductive roll assembly of the reversible rolling mill, a pulse current is applied to the strip (2), so that the pulse current acts continuously and synchronously in the rolling deformation zone and the post-rolling running zone. Step 4: Collect the temperature distribution and electrical parameters of the strip (2) in the width direction, and perform closed-loop correction on the zone heating parameters and / or pulse current parameters of the electromagnetic gradient heating component (412); Step 5: Switch the rolling direction and repeat steps 2 to 4.

10. The pulse current uniform loading method based on gradient temperature field modulation according to claim 9, characterized in that: The heating temperature of the strip (2) shall not exceed one-third of the recrystallization temperature of the strip (2).

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