A sizing device for CoreFlow TM Sizing device for aluminum alloy wire and method thereof

Abstract

The application discloses a kind of for CoreFlow TM The diameter sizing device and method of aluminum alloy wire rod include a wire rod collecting and pre-tensioning unit S1, a vibration friction composite finishing stage S2, a preheating temperature control unit S3, a flexible guide sizing unit S4, a micro-tension finishing unit S5, a dry self-lubricating finishing unit S6, a cooling and winding unit S7, and multiple wire feeding roller groups and guide roller groups that serve as guiding and supporting. The application efficiently converts CoreFlow™ aluminum alloy byproducts into usable wire rods, achieving material recycling and green manufacturing.

Description

Technical Field

[0001] This invention relates to the field of surface finishing technology for metal wires, and more particularly to a surface finishing method for CoreFlow. TM A sizing device and method for aluminum alloy wire. Background Technology

[0002] CoreFlow™ (TWI registered name) is a solid-state, subsurface processing technology developed by the Welding Institute (TWI) in the UK, derived from Friction Stir Welding (FSW) and its derivative Friction Stir Channeling (FSC) process. This process achieves intense plastic deformation and material rearrangement of metallic materials by introducing controlled channels / flow paths formed by the action of a stirring head within the workpiece. TWI's public information indicates that CoreFlow can be used to integrally form a subsurface channel network in a three-dimensional monolithic part and can "extrude" continuous wire / byproducts from sheet or tube for subsequent processing or as feedstock, offering high resource efficiency. It can transform materials that are difficult to directly filamentize or originate from byproducts (such as certain experimental alloys or recycled materials) into continuous wires, thus providing a new path for low-carbon, circular manufacturing chains. TWI and industry reports also mention that this method can continuously "extrude" wires of unlimited length from sheet or tube, providing a rapid and customizable source of raw materials for welding wire and wire additive manufacturing. During the operation of Stationary Shoulder Friction Stir Channelling (SS-FSC), the intense plastic flow generated along the stirring head path produces recyclable "forged" filaments (i.e., process byproducts). These filaments generated by SS-FSC / CoreFlow possess a refined grain structure (belonging to a dense / fine-grained structure formed after severe plastic deformation), and are therefore considered by researchers as a potential feedstock source for wire additive manufacturing (e.g., Directed Energy Deposition with a laser beam and wire feedstock, DED-LB / w). Recently, researchers have used these "SS-FSC byproduct filaments" in DED-LB / w experiments and conducted systematic studies on forming, melt state mapping, microstructure, and porosity defects. They pointed out that under optimized parameters, fine-grained (e.g., approximately 9 μm-20 μm) deposition structures can be obtained, but attention should also be paid to porosity issues caused by oxides / inclusions and gases.

[0003] It is important to note that CoreFlow™-generated wire may carry surface oxides, inclusions, or trapped gases during its formation and extraction (especially when raw material surface or environmental control is inadequate). Therefore, post-processing (such as deoxidation / shaping / cleaning) and process parameter optimization are often required before it can be directly used as a laser / heat source feed for DED or welding. Related research has indicated that these factors are major sources of forming porosity and recommends considering both material pretreatment and molten pool / atmosphere control when evaluating the use of CoreFlow™ wire in additive manufacturing. Therefore, when using CoreFlow™-generated aluminum alloy welding wire for actual welding or wire additive manufacturing, post-processing (such as sizing, surface cleaning, and polishing) is necessary to meet the surface finish and diameter consistency requirements of commercial welding wires. However, welding wires produced by this process often exhibit defects such as uneven diameter, rough surface, and noticeable burrs after initial extrusion. These defects not only affect the wire feeding stability and forming accuracy but may also lead to unstable metal transport and increased defects during laser additive manufacturing. Currently, traditional welding wire production mostly uses rigid die drawing and multiple cold drawing processes, which involve complex equipment and are not suitable for the "near-net-shape" wires produced by the CoreFlow™ process.

[0004] Therefore, there is an urgent need for a simple, adjustable, low-cost, and flexible new method for sizing and finishing welding wires to post-process CoreFlow™ aluminum alloy welding wires so that they meet the standards for commercial welding wires (smooth surface, consistent diameter, and no burrs). Summary of the Invention

[0005] Purpose of the invention: To address the shortcomings and defects of existing technologies, this invention provides a method for CoreFlow... TM A sizing device and method for aluminum alloy wires efficiently converts CoreFlow™ aluminum alloy byproducts into usable wires, enabling material recycling and green manufacturing.

[0006] Technical solution: The present invention is used for CoreFlow TMA sizing device for aluminum alloy wire, characterized in that it comprises, in sequence, a wire collection and pre-tensioning unit S1, a vibration-friction composite finishing stage S2, a preheating and temperature control unit S3, a flexible guiding sizing unit S4, a micro-tension finishing unit S5, a dry self-lubricating finishing unit S6, a cooling and winding unit S7, and multiple wire feeding roller groups and guide roller groups that provide guidance and support; the wire collection and pre-tensioning unit S1 unfolds, straightens, and initially controls the tension of the aluminum alloy wire; the vibration-friction composite finishing stage S2 removes burrs and micro-protrusions from the surface of the aluminum alloy wire and shapes its surface; the preheating... Temperature control unit S3 reduces internal stress in aluminum alloy wire by uniform heating, improves metal plasticity, and enhances deformation coordination in subsequent sizing processes; flexible guiding sizing unit S4 continuously compacts and rounds the aluminum alloy wire, achieving consistent diameter control; micro-tension finishing unit S5 eliminates ripples or elliptical deviations generated in previous processes and corrects the diameter of the aluminum alloy wire again; dry self-lubricating finishing unit S6 performs final surface finishing on the aluminum alloy wire and forms a protective film; cooling and winding unit S7 achieves gradual temperature reduction, stress release, and winding of the aluminum alloy wire.

[0007] The wire collection and pre-tensioning unit S1 includes an aluminum alloy wire unwinding mechanism, a constant tension control component, and a straightening roller group connected in sequence. The straightening roller group adopts a staggered multi-roller path structure, such as an S-shaped or Z-shaped arrangement, so that the aluminum alloy wire is subjected to multiple bending and reverse bending during the process, thereby effectively eliminating its initial curling, knotting, and internal stress. The constant tension control component includes a servo motor and a tension sensor for adjusting the output of the servo motor. The tension applied to the aluminum alloy wire by the servo motor is maintained at 0.5N-1.0N, so that the aluminum alloy wire maintains a micro-plastic extension state along the axial direction, ensuring the consistency of the straightness of the aluminum alloy wire, and laying a geometrically stable foundation for subsequent sizing and surface finishing.

[0008] The vibration-friction composite finishing stage S2 includes a vibration groove and a vibration drive module. The vibration groove is filled with abrasive particles. The groove is 0.3m-0.8m long and lined with a corrugated flexible wear-resistant layer made of polyurethane or nitrile rubber. The abrasive particles are 100μm-300μm in diameter. A raised structure, 15mm high and 40mm wide, is added to the bottom of the groove to facilitate irregular movement of the abrasive particles. Three such raised structures are placed. The abrasive material is alumina, silicon carbide, or nylon balls, and the filling ratio is 30%-0% of the groove volume. The vibration drive module uses a vertically superimposed horizontal composite vibration, with the vibration frequency controlled between 20Hz and 40Hz. The two vibration modes alternate, each lasting 30s-60s. A composite vibration mode at a certain frequency, combined with the corrugated flexible wear-resistant layer protrusions within the groove, subjectes the aluminum alloy wire to frictional forces in all directions, effectively removing burrs and micro-protrusions from the wire's surface and shaping its shape. The vibration drive module preferably employs a dual-eccentric vibration motor synchronous drive structure, such as the VB-32154-W type small vibration motor, with two motors arranged in opposite directions to create composite vibrations in the horizontal and vertical directions. The vibration frequency is adjusted to the range of 20Hz-40Hz via a frequency converter to drive the abrasive particles within the groove to form continuous tumbling and frictional motion.

[0009] The preheating temperature control unit S3 employs a resistance heating tube, infrared heater, or hot air circulation furnace for heating, forming a closed or semi-closed heating channel. The temperature of the heating channel is controlled between 100℃ and 180℃, and the heating rate is controlled to avoid excessive local overheating and damage to the aluminum alloy wire. The length of the heating channel is 0.3m-0.8m to ensure that the aluminum alloy wire stays in the preheating temperature control unit for a sufficient time, allowing its lattice defects to be repaired and its plasticity to be improved. This prevents wire breakage or surface cracks during subsequent flexible guiding and sizing processes, thereby achieving continuous and high-quality processing. This solution is applicable to the flexible sizing of various metal wires. The heating temperature, heating channel length, and heating rate are adjusted according to the matching of different metal wires to improve the processing performance of subsequent flexible sizing of the metal wire.

[0010] The flexible guiding and sizing unit S4 includes several sizing rings arranged sequentially along the travel direction of the aluminum alloy wire, with adjustable gaps. The guide rings are made of polytetrafluoroethylene, polyamide, or wear-resistant silicone rubber, and their inner walls have a micro-elastic deformation structure. The micro-elastic deformation structure consists of elastic ribs or corrugated structures arranged circumferentially along the travel direction of the aluminum alloy wire. The sizing rings have a linearly decreasing aperture design, with a decreasing gradient ≤0.02mm and 4-8 decreasing stages. A circumferential wedge structure can be arranged on the inner wall surface along the axial direction to gradually stretch the wire. The height of the wedge structure is 0.03mm–0.07mm, and the wedge angle is 45°. To avoid scratches, a low-friction coating or lubricant (dry film lubrication) may be used if necessary. The sizing rings have a linearly decreasing aperture design, from slightly larger than the maximum wire feed to close to the target value, with a decreasing gradient ≤0.02mm and 4-8 decreasing stages. When the aluminum alloy wire passes through multiple sizing rings, under the dual action of axial traction force and radial pressure, its diameter gradually approaches the ideal roundness, improving the uniformity of the diameter and controlling the diameter error within ±0.01mm. At the same time, it avoids the stress concentration and surface scratch problems existing in the traditional hard die drawing process.

[0011] The micro-tension fine-tuning unit S5 includes a closed-loop tension control traction component, a wire breakage protection module, and a control module. The closed-loop tension control traction component applies a constant axial micro-tension of 0.5N-5N via a servo drive device (keeping the welding wire in a 1%-3% micro-tension state to maintain a stable micro-deformation rate). Real-time tension detection monitors the applied micro-tension fluctuation within ±10%. If the fluctuation exceeds this range, the micro-tension is automatically adjusted to a controllable range to avoid over-stretching or under-stretching, achieving uniform and high-precision control of the welding wire diameter. The adjustment range of the traction speed should not be too large to avoid overcompensation. Furthermore, the adjustment and recovery of the traction speed should be completed within 10ms-50ms to achieve real-time response and rapid adjustment. By setting a maximum allowable tension threshold and wire breakage protection logic, when the real-time detected tension exceeds the preset wire breakage threshold, the system automatically decelerates and stops, and the entire production line stops operating to avoid wire breakage or process damage.

[0012] The micro-tension fine-tuning unit S5 includes an online diameter measurement feedback module. This module uses a laser diameter gauge to monitor diameter changes in real time. When the system detects a diameter deviation greater than a threshold, it adjusts the traction speed through a closed-loop adjustment mechanism to maintain stable sizing accuracy. The adjustment range of the traction speed is ±0.5%-2%. Specifically, when the system detects a diameter deviation ≥ ±0.05mm, it automatically adjusts the traction tension provided by the individual servo drive motor built into the micro-tension fine-tuning unit through a closed-loop control algorithm. The diameter measurement signal, after error calculation and combined with a PID (proportional-integral-derivative) control algorithm, drives the servo motor of the closed-loop tension control traction component to fine-tune the traction speed within the range of ±0.5%-2% (increasing the traction speed to increase the tensile strain rate when the diameter is too large; decreasing the traction speed to reduce the tensile strain rate when the diameter is too small). Through this dynamic feedback adjustment mechanism, the accuracy and effectiveness of sizing are monitored in a timely manner. When the sizing accuracy does not meet the expected value, the traction tension of the built-in servo drive motor is adjusted promptly to ensure the effectiveness and accuracy of sizing.

[0013] The dry self-lubricating finishing unit S6 employs a dry lubricator, including a flexible felt guide hole containing graphite and / or molybdenum disulfide, and an inert gas protection component. The length of the flexible felt guide hole is 8mm-20mm (preferably 12mm), and the hole diameter is 0.01mm-0.02mm smaller than the target diameter. The graphite particle size is 1μm-10μm, and the molybdenum disulfide particle size is 1μm-50μm. Graphite or molybdenum disulfide can be used alone or in combination. The aluminum alloy wire passes through the flexible felt guide hole at a speed of 0.2m / s-0.5m / s in an inert atmosphere. The aluminum alloy wire and the flexible felt experience uniform micro-contact sliding friction, further plasticizing the surface layer, further eliminating burrs, and smoothing surface grooves. Simultaneously, the graphite / MoS2 particles form a self-lubricating protective film on the surface, providing both polishing and anti-oxidation functions, thereby significantly reducing surface roughness and improving the corrosion resistance of the welding wire. The aluminum alloy material undergoes final finishing treatment in a dry self-lubricating finishing unit, forming a self-lubricating and anti-oxidation protective film on the surface of the welding wire in situ. This improves the surface quality and long-term storage stability of the welding wire. Compared with the traditional wet polishing process, this method does not use liquid polishing agents and can achieve continuous and automated production.

[0014] The cooling and winding unit S7 includes a cooling channel, a constant-speed tension control reel, and an inert gas protection assembly. The cooling channel is equipped with a controllable airflow or water-cooling jacket, achieving a cooling rate of 3℃ / s-6℃ / s for the aluminum alloy wire. Adjusting the length of the cooling channel ensures the aluminum alloy wire slowly cools to room temperature. During cooling, the aluminum alloy wire is protected by an inert gas to prevent oxidation or moisture absorption. The constant-speed tension control reel maintains a constant tension of 0.5N-1.5N during winding, preventing reverse curling or residual stress concentration during cooling. Through this unit, the wound aluminum alloy wire is neat and dense, with a diameter error generally controlled within ±0.005mm. The wire surface has a high smoothness, tight winding, and stable mechanical properties.

[0015] The present invention for CoreFlow TM A method for sizing aluminum alloy wire, characterized by comprising the following steps:

[0016] 1) Wire collection and pre-tensioning straightening stage: A constant tension is applied to the CoreFlow™ aluminum alloy wire, which is straightened by a staggered straightening roller group to eliminate curling, knotting and internal stress, creating conditions for subsequent uniform deformation;

[0017] 2) Vibration-friction composite finishing stage: CoreFlow™ aluminum alloy wire passes through a vibration groove with a flexible wear-resistant inner wall under constant tension. The groove is filled with abrasive particles, and the surface burrs are eliminated through the synergistic effect of tension and friction between the abrasive particles.

[0018] 3) Temperature-controlled guiding stage: The CoreFlow™ aluminum alloy wire obtained after the pre-tensioning and straightening stage process is uniformly preheated to reduce the residual stress inside the aluminum alloy wire and improve its plasticity;

[0019] 4) Flexible guiding sizing stage: CoreFlow™ aluminum alloy wire passes through multiple adjustable sizing rings in sequence, achieving continuous compaction and rounding of the wire's outer diameter under micro-tension control;

[0020] 5) Micro-tension finishing stage: A constant tension is applied to the aluminum alloy wire through a synchronously controlled linear traction system, which redistributes the plastic strain on the surface of the CoreFlow™ aluminum alloy wire and eliminates diameter fluctuations;

[0021] 6) Dry self-lubricating finishing stage: Under low temperature and inert atmosphere, CoreFlow™ aluminum alloy wire is passed through the guide holes of a flexible felt cloth containing graphite powder or molybdenum disulfide micro powder. The surface finishing of the aluminum alloy wire and the in-situ formation of the protective film are achieved by using micro-friction sliding action, thereby obtaining CoreFlow™ aluminum alloy wire with a smooth surface and anti-oxidation properties.

[0022] 7) Cooling and winding stage: After finishing, the filament is slowly cooled to room temperature in an inert atmosphere and then wound at a constant speed to obtain filament with uniform diameter and smooth surface.

[0023] Beneficial effects: Compared with the prior art, the present invention has the following significant advantages:

[0024] 1) The sizing device provided by the present invention has a simple and compact structure and can operate continuously. It does not require complex wire drawing dies and cold working equipment. It can effectively eliminate the problems of uneven diameter and surface burrs of CoreFlow™ aluminum alloy welding wire without damaging the welding wire structure, and achieve diameter uniformity and surface smoothness.

[0025] 2) By introducing thermo-mechanical synergy, the welding wire is rolled and stretched under controlled temperature by a flexible guide ring, which achieves uniformity of the welding wire diameter and surface smoothing. Compared with the traditional method, the surface smoothness is improved by 1-2 orders of magnitude, Ra≤0.8μm, the diameter fluctuation is reduced to ±0.03mm, and the roundness is improved by 0.05%.

[0026] 3) The micro-adjustment spiral structure is used for elastic sizing, which automatically compensates for the diameter deviation of the welding wire, avoids the tearing and wire breakage problems caused by traditional rigid molds, and reduces the fluctuation of wire diameter.

[0027] 4) After sizing, a constant tension is applied to the aluminum alloy wire through a synchronously controlled linear traction system, which redistributes the plastic strain of the wire and further reduces the fluctuation of the wire diameter.

[0028] 5) The equipment can be modularly constructed, has good versatility, and the process is free of coolant pollution. It is suitable for multiple series of aluminum alloy welding wires such as Al-Mg-Si, Al-Mg and Al-Zn-Mg. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the present invention;

[0030] Figure 2 This is a schematic diagram of the structure of the wire collection and pre-tensioning unit S1 of the present invention;

[0031] Figure 3 This is a schematic diagram of the vibration-friction composite finishing stage S2 and the preheating temperature control unit S3 of the present invention;

[0032] Figure 4 This is a schematic diagram of the flexible guide sizing unit S4 and the micro-tension finishing unit S5 of the present invention;

[0033] Figure 5 This is a schematic diagram of the dry self-lubricating finishing unit S6 and the cooling and winding unit S7 of the present invention.

[0034] Figure 6 This is a schematic diagram of the internal structure of the vibration groove of the present invention;

[0035] Figure 7 This is a schematic diagram of the sizing ring of the present invention;

[0036] In the figure, 1 is the aluminum alloy wire unwinding mechanism; 2 is the aluminum alloy wire; 3 is the base plate of the wire feeding roller group; 4 is the constant tension control component; 5 is the straightening roller group; 6 is the wire feeding roller group; 7 is the vibration groove; 8 is the heating channel; 9 is the sizing ring; 10 is the guide roller group; 11 is the closed-loop tension control traction component; 12 is the dry lubricator; and 13 is the constant speed tension control reel. Detailed Implementation

[0037] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0038] Example:

[0039] like Figures 1-7 This embodiment is used for CoreFlow TM The sizing device for aluminum alloy wire includes, in sequence, a wire collection and pre-tensioning unit S1, a vibration-friction composite finishing stage S2, a preheating temperature control unit S3, a flexible guiding sizing unit S4, a micro-tension finishing unit S5, a dry self-lubricating finishing unit S6, and a cooling and winding unit S7, and also includes a wire feeding roller group 6 and a guide roller group 10. The sizing device of this invention employs a centralized control system, including a central PLC (Programmable Logic Controller), to which all unit sensors and actuators are connected. The main traction power for the entire device is provided by the constant-speed tension control reel 13 of the cooling and winding unit S7, ensuring the wire travels stably at a set linear speed. The wire collection and pre-tensioning unit S1 to the flexible guiding sizing unit S4 are in a "low-tension shaping" mode, maintaining only the basic tension to eliminate bending. The micro-tension finishing unit S5, as a precise tension adjustment node, has a closed-loop tension control traction component that performs fine adjustments of ±0.5%-2% based on the main traction speed to achieve precise sizing. Through the tension gradient and cascade speed control logic set by the central PLC, each unit works in coordination to avoid functional conflicts. The wire feeding roller group 6 is located above the wire feeding roller group base plate 3.

[0040] The wire collection and pre-tensioning unit S1 includes an aluminum alloy wire unwinding mechanism 1, a constant tension control component 4, and a straightening roller group 5 connected in sequence. The vibration-friction composite finishing stage S2 includes a vibration groove 7 and a vibration drive module. The vibration groove 7 is filled with abrasive particles. The length of the vibration groove 7 is 0.5m (0.3m-0.8m can be selected according to the friction finishing requirements). The groove is lined with a corrugated flexible wear-resistant layer. The lining material is polyurethane (or nitrile rubber). The groove is filled with abrasive particles with a particle size of 100μm-300μm. The abrasive material is alumina (silicon carbide or nylon balls). The filling ratio is 50% of the groove volume (30%-70% can be selected according to the friction finishing requirements). The vibration mode of the vibration drive module is vertical superimposed horizontal composite vibration. The two vibration modes alternate, and each vibration mode lasts for 60s. The preheating temperature control unit S3 uses resistance heating tubes (infrared heaters or hot air circulating furnaces) for heating, forming a closed or semi-closed heating channel 8. A temperature sensor and control system are used to construct a closed-loop control mechanism. The surface temperature signal of the aluminum alloy wire 2 is collected in real time, and the heating power is dynamically adjusted using a PID control algorithm. The temperature of the resistance heating tube is controlled at approximately 150℃. The length of the heating channel 8 is 0.5m (depending on the diameter of the aluminum alloy wire 2, the temperature range is 100℃-180℃, and the length of the heating channel 8 is selected from 0.3m to 0.8m). Simultaneously, the traction force of the adjustment system, combined with the selected length of the heating channel 7, adjusts the residence time of the aluminum alloy wire 2 in the heating zone, thereby achieving adaptive control of the holding time. When the detected temperature is lower than the set value, the system automatically reduces the linear speed to extend the heating time; when the temperature exceeds the upper limit, the linear speed is increased to shorten the heat exposure time and avoid overheating, thus achieving coordinated optimization control of the heating rate and holding time. Through this preheating treatment, the lattice defects of the aluminum alloy wire 2 are partially recovered, and the plasticity is improved, which helps to avoid wire breakage or surface cracks in the subsequent flexible guiding and sizing process, thereby achieving continuous and high-quality processing.

[0041] The traction power of this device is provided by the cooling and winding unit S7 at the rear end. The aluminum alloy wire 2 is pulled forward by the constant speed tension control reel 13 at the rear end, passing through each processing unit in sequence. In order to ensure the smooth operation of the wire in the heating zone, the wire collection and pre-tensioning unit S1 at the front end provides auxiliary unwinding tension through the constant tension control component 4. This tension value (0.5N-1.0N) is less than the traction force at the rear end, ensuring that the wire is in a straight state before entering the heating channel 8, avoiding wire loosening or accumulation due to heating and softening.

[0042] The flexible guiding sizing unit S4 includes several sizing rings 9 arranged sequentially along the traveling direction of the aluminum alloy wire 2, with adjustable gaps. The sizing rings 9 are made of polytetrafluoroethylene, polyamide, or wear-resistant silicone rubber. The inner wall surface can be provided with a circumferential wedge structure along the axial direction to gradually stretch the wire. The height of the wedge structure is 0.03mm-0.07mm, and the wedge angle is 45°. The sizing rings 9 have a linearly decreasing aperture design in three stages (4-8 stages can also be set depending on the difference between the target diameter and the raw material diameter, with a decreasing gradient ≤0.02mm). Let the target aluminum alloy wire 2 diameter be dt. Then, the inner diameter of the final sizing ring is set slightly smaller than the target diameter, preferably dt−(0.01-0.05)mm, to generate a moderate radial compression effect when the aluminum alloy wire 2 passes through. Due to the elasticity of the sizing ring material, the aluminum alloy wire 2 undergoes a "compression-springback" behavior during its passage, thereby achieving dimensional convergence and stabilization within the target diameter range. The difference in inner diameter between adjacent sizing rings is controlled within the range of 0.01mm-0.05mm, allowing the aluminum alloy wire 2 to undergo gradual plastic deformation, thus avoiding the risk of surface scratches or breakage caused by excessive deformation in a single step. The flexible guiding sizing unit S4 is positioned after the preheating temperature control unit S3, achieving continuous and stable flexible sizing under the system's traction force, thereby significantly improving the diameter consistency and roundness of the aluminum alloy wire 2. As the aluminum alloy wire 2 passes through multiple sizing rings 9, under the dual action of axial tension and radial light pressure, its cross-section gradually approaches the ideal roundness. Locally excessively large diameter portions are plastically flattened, while excessively small diameter portions recover, achieving continuous sizing. This structure not only improves the uniformity of the welding wire diameter (error can be controlled within ±0.01mm) but also avoids the stress concentration and surface scratch problems present in traditional hard die drawing processes.

[0043] Under the traction force of the system, the aluminum alloy wire 2 passes sequentially through the sizing rings 9 with linearly decreasing apertures. This unit does not have an independent power drive, but relies on the main traction force provided by the rear winding unit, combined with the radial constraint of the sizing rings, to achieve continuous compaction and rounding of the wire. The difference in inner diameter between adjacent sizing rings 9 is controlled within the range of 0.01mm-0.05mm.

[0044] The micro-tension finishing unit S5 includes a closed-loop tension control traction component 11, a wire breakage protection module, an online diameter measurement feedback module, and a control module. The closed-loop tension control traction component 11 applies a constant axial micro-tension of 0.5N-5N via a servo drive device, with micro-tension fluctuations controlled within ±10%. If the fluctuation exceeds this range, it automatically adjusts back to within the range. The online diameter measurement feedback module detects the diameter of the aluminum alloy wire 2 processed by the micro-tension finishing unit S5 in real time. When the diameter differs from the expected value by more than a threshold, the closed-loop control algorithm automatically adjusts the preset traction tension value of the closed-loop tension control traction component 11. The measured value is compared with the target diameter to obtain a diameter deviation signal. The control module constructs a closed-loop control model based on this deviation signal, calculates the correction amount for the traction speed using a PID adjustment algorithm, and sends the adjustment command to the servo drive device of the closed-loop tension control traction component 11 to dynamically adjust the running speed of the aluminum alloy wire 2. When the diameter of the aluminum alloy wire 2 is detected to be too large, the traction speed is increased to increase the axial micro-stretch rate, causing further plastic deformation of the aluminum alloy wire 2 and thus reducing the diameter. When the diameter of the aluminum alloy wire 2 is detected to be too small, the traction speed is reduced to weaken the stretching effect and prevent excessive diameter reduction. The adjustment of the traction force is continuously performed at a control frequency of 1Hz-10Hz, combined with the upper limit of tension and the speed change rate limit, to achieve stable and continuous diameter closed-loop control, thereby effectively suppressing radial fluctuations and improving dimensional consistency. Through this process, the microscopic plastic deformation of the surface layer of the aluminum alloy wire 2 is redistributed, effectively eliminating the ripples or elliptical deviations generated in the previous sizing stage, achieving continuous and precise diameter correction. Compared with traditional forming methods, this method has lower deformation temperature, lower energy consumption, and more uniform surface stress.

[0045] The closed-loop tension control traction component 11 acts as the system's "fine-tuning unit," with its base speed following the operating speed of the downstream winding unit S7. The online diameter measurement feedback module detects the filament diameter in real time and feeds the signal back to the control module. Based on a PID algorithm, the control module fine-tunes the rotational speed of the closed-loop tension control traction component 11 within a range of ±0.5%-2%. When a diameter is detected to be too large, component 11 instantly increases its speed, increasing the axial micro-stretch rate to reduce the diameter; when a diameter is detected to be too small, component 11 instantly decelerates, reducing the stretch to restore the diameter. This micro-amplitude dynamic adjustment based on the main speed chain corrects diameter fluctuations without disrupting the synchronization of the entire production line. Simultaneously, the filament breakage protection module monitors the tension sensor signal in real time, immediately triggering a shutdown protection mechanism once the tension exceeds the safety threshold.

[0046] The dry self-lubricating finishing unit S6 uses a dry lubricator 12. The dry lubricator 12 has built-in flexible felt guide holes containing graphite (and / or molybdenum disulfide, with a particle size of 1μm-50μm) and an inert gas protection component. The length of the flexible felt guide holes is preferably 12mm, and the hole diameter is 0.01mm-0.02mm smaller than the target diameter. The graphite particle size is preferably 5μm. The aluminum alloy wire passes through the flexible felt guide holes at a speed of 0.2m / s-0.5m / s in an inert atmosphere. The cooling and winding unit S7 includes a cooling channel, a constant speed tension control reel 13, and an inert gas protection component. The cooling channel is equipped with a controllable airflow or water-cooling jacket. The cooling rate of the aluminum alloy wire 2 is 3℃ / s-6℃ / s. The constant speed tension control reel 13 maintains a constant tension of 0.5N-1.5N during winding.

[0047] An inert gas (such as argon) is introduced into the cooling channel to slowly cool the filament at a rate of 3°C to 6°C per second, while simultaneously forming a protective air curtain to prevent oxidation of the high-temperature filament. The constant-speed tension control reel 13 serves as the main driving force for the entire production line, maintaining a constant tension of 0.5N to 1.5N during winding. Because each of the front-end units (S1-S6) employs a passive guiding or following control strategy, the filament is ultimately wound smoothly under the protection of the inert atmosphere, resulting in a finished product with a smooth surface and uniform diameter.

[0048] This embodiment is used for CoreFlow TM A method for sizing aluminum alloy wire, characterized by comprising the following steps:

[0049] 1) Wire collection and pre-tensioning straightening stage: A constant tension is applied to the CoreFlow™ aluminum alloy wire, which is straightened by a staggered straightening roller group to eliminate curling, knotting and internal stress, creating conditions for subsequent uniform deformation;

[0050] 2) Vibration-friction composite finishing stage: CoreFlow™ aluminum alloy wire passes through a vibration groove with a flexible wear-resistant inner wall under constant tension. The groove is filled with abrasive particles, and the surface burrs are eliminated through the synergistic effect of tension and friction between the abrasive particles.

[0051] 3) Temperature-controlled guiding stage: The CoreFlow™ aluminum alloy wire obtained after the pre-tensioning and straightening stage process is uniformly preheated to reduce the residual stress inside the aluminum alloy wire and improve its plasticity;

[0052] 4) Flexible guiding sizing stage: CoreFlow™ aluminum alloy wire passes through multiple adjustable sizing rings in sequence, achieving continuous compaction and rounding of the wire's outer diameter under micro-tension control;

[0053] 5) Micro-tension finishing stage: A constant tension is applied to the aluminum alloy wire through a synchronously controlled linear traction system, which redistributes the plastic strain on the surface of the CoreFlow™ aluminum alloy wire and eliminates diameter fluctuations;

[0054] 6) Dry self-lubricating finishing stage: Under low temperature and inert atmosphere, CoreFlow™ aluminum alloy wire is passed through the guide holes of a flexible felt cloth containing graphite powder or molybdenum disulfide micro powder. The surface finishing of the aluminum alloy wire and the in-situ formation of the protective film are achieved by using micro-friction sliding action, thereby obtaining CoreFlow™ aluminum alloy wire with a smooth surface and anti-oxidation properties.

[0055] 7) Cooling and winding stage: After finishing, the filament is slowly cooled to room temperature in an inert atmosphere and then wound at a constant speed to obtain filament with uniform diameter and smooth surface.

[0056] To address the issues of numerous burrs, uneven diameter, and rough surface in aluminum alloy wire 2 produced by the CoreFlow™ process using byproducts of the Friction Stir Channelling (FSC) process, a seven-step continuous shaping and surface finishing process is employed. In the sizing stage, an adjustable heating guide device is introduced to heat and repair lattice defects, improve plasticity, and prevent wire breakage or surface cracking during subsequent flexible guiding sizing, thus achieving continuous, high-quality processing. In subsequent stages, a closed-loop control system with constant micro-tension dynamically corrects the wire tension to eliminate radial fluctuations. Finally, dry polishing is performed through guide holes in a flexible felt cloth containing graphite or MoS2 to achieve surface smoothing and the formation of an anti-oxidation film. The micro-tension finishing stage also includes a wire breakage protection module. When the real-time detected tension exceeds the preset wire breakage threshold, the system automatically slows down and stops to avoid wire breakage or process damage, ensuring the safety of the sizing process. The micro-tension finishing stage also includes an online diameter measurement feedback module, which monitors the sizing accuracy of the wire after the micro-tension finishing stage in real time. When the difference from the expected value exceeds the threshold, the preset traction tension value of the servo drive device is automatically adjusted through a closed-loop control algorithm to ensure the effectiveness and accuracy of wire sizing. Compared with traditional mechanical wire drawing or simple polishing methods, this method is simpler, more automated, produces no lubricant contamination, and can be directly connected to the CoreFlow™ wire making device. After treatment, the diameter consistency of the aluminum alloy wire is significantly improved, with the diameter standard deviation reduced from ±0.15mm to ±0.03mm and the surface roughness Ra reduced to below 0.8μm.

Claims

1. A tool for CoreFlow TM A sizing device for aluminum alloy wire, characterized in that: The system includes a wire collection and pre-tensioning unit S1, a vibration-friction composite finishing stage S2, a preheating and temperature control unit S3, a flexible guiding and sizing unit S4, a micro-tension finishing unit S5, a dry self-lubricating finishing unit S6, a cooling and winding unit S7, and multiple wire feeding roller groups (6) and guide roller groups (10) that provide guidance and support. The wire collection and pre-tensioning unit S1 unfolds, straightens, and performs preliminary tension control on the aluminum alloy wire. The vibration-friction composite finishing stage S2 removes burrs and micro-protrusions from the surface of the aluminum alloy wire and shapes its surface. The preheating and temperature control unit S4...

3. Uniform heating reduces internal stress in the aluminum alloy wire, improves metal plasticity, and enhances deformation coordination in subsequent sizing processes. The flexible guiding sizing unit S4 continuously compacts and rounds the aluminum alloy wire, achieving consistent control of its diameter. The micro-tension finishing unit S5 eliminates ripples or elliptical deviations generated in the previous process and corrects the aluminum alloy wire diameter again. The dry self-lubricating finishing unit S6 performs final finishing on the surface of the aluminum alloy wire and forms a protective film. The cooling and winding unit S7 achieves gradual temperature reduction, stress release, and winding of the aluminum alloy wire.

2. The CoreFlow as described in claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The wire collection and pre-tensioning unit S1 includes an aluminum alloy wire unwinding mechanism (1), a constant tension control component (4), and a straightening roller group (5) connected in sequence. The straightening roller group (5) adopts a staggered multi-roller path structure. The constant tension control component (4) includes a servo motor and a tension sensor for adjusting the output of the servo motor. The tension applied to the aluminum alloy wire (2) by the servo motor is maintained at 0.5N-1.0N.

3. The CoreFlow as described in claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The vibration-friction composite finishing stage S2 includes a vibration groove (7) and a vibration drive module; the vibration groove (7) is filled with abrasive particles, the length of the vibration groove (7) is 0.3m-0.8m, the inner lining of the groove is a wave-shaped flexible wear-resistant layer, the inner lining material is polyurethane or nitrile rubber, the groove is filled with abrasive particles with a particle size of 100μm-300μm, the abrasive material is alumina, silicon carbide or nylon balls, and the filling ratio is 30%-70% of the groove volume; the vibration mode of the vibration drive module is vertical superimposed horizontal composite vibration.

4. The CoreFlow as described in claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The preheating temperature control unit S3 uses a resistance heating tube, an infrared heater or a hot air circulating furnace for heating to form a closed or semi-closed heating channel (8). The temperature of the heating channel (8) is controlled at 100℃-180℃ and the length of the heating channel (8) is 0.3m-0.8m.

5. The CoreFlow as described in claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The flexible guide sizing unit S4 includes several sizing rings (9) arranged sequentially along the traveling direction of the aluminum alloy wire (2) with adjustable gaps. The guide ring material is selected from polytetrafluoroethylene, polyamide or wear-resistant silicone rubber, and the inner wall has a micro-elastic deformation structure. The micro-elastic deformation structure is an elastic rib or corrugated structure arranged circumferentially along the traveling direction of the aluminum alloy wire (2). The sizing ring (9) has a linear decreasing aperture design with a decreasing gradient ≤0.02mm and a decreasing level of 4-8.

6. The CoreFlow as described in claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The micro-tension finishing unit S5 includes a closed-loop tension control traction component (11); the closed-loop tension control traction component (11) applies a constant axial micro-tension of 0.5N-5N through a servo drive device, and the closed-loop tension control traction component (11) is equipped with a wire breakage protection module and a control module.

7. The CoreFlow as described in claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The micro-tension finishing unit S5 includes an online diameter measurement feedback module; the online diameter measurement feedback module uses a laser diameter gauge to monitor diameter changes in real time. When the system detects that the diameter deviation is greater than the threshold, it adjusts the traction speed through a closed-loop adjustment mechanism to maintain stable sizing accuracy. The adjustment range of the traction speed is ±0.5%-2%.

8. The CoreFlow application according to claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The dry self-lubricating finishing unit S6 uses a dry lubricator (12), which includes a flexible felt guide hole containing graphite and / or molybdenum disulfide, and an inert gas protection component; the length of the flexible felt guide hole is 8mm-20mm, and the hole diameter is 0.01mm-0.02mm smaller than the target diameter; the particle size of the graphite is 1μm-10μm, the particle size of the molybdenum disulfide is 1μm-50μm, and the aluminum alloy wire (2) passes through the flexible felt guide hole at a speed of 0.2m / s-0.5m / s in an inert atmosphere.

9. The CoreFlow application according to claim 1 TM A sizing device for aluminum alloy wire, characterized in that: The cooling and winding unit S7 includes a cooling channel, a constant speed tension control reel (13), and an inert gas protection component; the cooling channel is equipped with a controllable airflow or water cooling jacket, and the cooling rate of the aluminum alloy wire (2) is 3℃ / s-6℃ / s; the constant speed tension control reel (13) maintains a constant tension of 0.5N-1.5N for winding.

10. A method for CoreFlow TM A method for sizing aluminum alloy wire, characterized in that: Includes the following steps: 1) Wire collection and pre-tensioning straightening stage: A constant tension is applied to the CoreFlow™ aluminum alloy wire, which is straightened by a staggered straightening roller group to eliminate curling, knotting and internal stress, creating conditions for subsequent uniform deformation; 2) Vibration-friction composite finishing stage: CoreFlow™ aluminum alloy wire passes through a vibration groove with a flexible wear-resistant inner wall under constant tension. The groove is filled with abrasive particles, and the surface burrs are eliminated through the synergistic effect of tension and friction between the abrasive particles. 3) Temperature-controlled guiding stage: The CoreFlow™ aluminum alloy wire obtained after the pre-tensioning and straightening stage process is uniformly preheated to reduce the residual stress inside the aluminum alloy wire and improve its plasticity; 4) Flexible guiding sizing stage: CoreFlow™ aluminum alloy wire passes through multiple adjustable sizing rings in sequence, achieving continuous compaction and rounding of the wire's outer diameter under micro-tension control; 5) Micro-tension finishing stage: A constant tension is applied to the aluminum alloy wire through a synchronously controlled linear traction system, which redistributes the plastic strain on the surface of the CoreFlow™ aluminum alloy wire and eliminates diameter fluctuations; 6) Dry self-lubricating finishing stage: Under low temperature and inert atmosphere, CoreFlow™ aluminum alloy wire is passed through the guide holes of a flexible felt cloth containing graphite powder or molybdenum disulfide micro powder. The surface finishing of the aluminum alloy wire and the in-situ formation of the protective film are achieved by using micro-friction sliding action, thereby obtaining CoreFlow™ aluminum alloy wire with a smooth surface and anti-oxidation properties. 7) Cooling and winding stage: After finishing, the filament is slowly cooled to room temperature in an inert atmosphere and then wound at a constant speed to obtain filament with uniform diameter and smooth surface.

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