Surface treatment method for conductive steel roller for copper foil

Abstract

The application relates to the technical field of steel roller surface treatment, and discloses a copper foil conductive steel roller surface treatment method, which comprises the following steps: S1, pre-treating the surface of the conductive steel roller, wherein the pre-treatment comprises ultrasonic cleaning and anhydrous ethanol wiping; S2, based on the pre-treated conductive steel roller and according to the initial roughness and the target roughness of the conductive steel roller, setting laser average power, pulse frequency, pulse width, light spot diameter, axial feeding speed, radial feeding step distance and scanning overlap rate; and S3, based on the setting, performing online laser grinding, so that the laser processing head spirally scans the surface of the steel roller along the axial direction and the radial direction at the set feeding speed and step distance while the steel roller rotates by itself, and the surface convex peaks are removed through laser. Through laser grinding and real-time feedback control technology, the application realizes accurate adjustment of the surface roughness and shape of the steel roller, improves the consistency of the processing efficiency and the surface quality, and ensures high precision and uniformity.

Description

Technical Field

[0001] This invention relates to the field of steel roller surface treatment technology, specifically to a method for surface treatment of conductive steel rollers for copper foil. Background Technology

[0002] In modern manufacturing, steel rollers are indispensable components in numerous precision machining and surface treatment processes, widely used in industries such as copper foil, batteries, and coatings. In these applications, the surface quality of the steel rollers directly affects the performance and stability of subsequent products. Therefore, improving the precision, smoothness, and uniformity of the steel roller surface has become a critical technical requirement.

[0003] In existing technologies, steel roller surface treatment methods mainly employ traditional processes such as mechanical grinding and chemical polishing. The advantages of these techniques are that mechanical grinding can effectively remove some larger protrusions and defects on the steel roller surface, while chemical polishing can improve surface smoothness and reduce friction. However, these methods typically rely on manual operation, making it impossible to guarantee completely consistent treatment results for each workpiece. While mechanical grinding has certain advantages in removing surface defects, it often fails to provide uniform surface smoothness. Although chemical polishing can achieve good smoothness, it struggles to meet higher requirements for controlling the surface precision of the steel roller.

[0004] However, existing technologies have some shortcomings. First, mechanical grinding is inefficient and unstable, relying on manual operation, which often makes it impossible to guarantee precise control of roughness and shape during processing, resulting in significant differences between workpieces. Second, traditional processing methods often use linear scanning paths, which makes the surface treatment effect uneven and easily leaves obvious processing marks or streaks on the steel roller surface, affecting the quality of subsequent processes. During cleaning and post-treatment, existing technologies still struggle to completely remove surface impurities, easily causing residual water droplets or oil stains to interfere with subsequent inspections, reducing the accuracy and stability of surface treatment. These problems all affect the quality of steel rollers in production, leading to instability and inconsistency in their subsequent use. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a surface treatment method for conductive steel rollers used for copper foil, which solves the problems of low surface treatment precision, uneven processing results, and excessive manual intervention in existing technologies.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a surface treatment method for a conductive steel roller for copper foil, comprising the following steps:

[0007] S1. Pre-treat the surface of the conductive steel roller, the pre-treatment including ultrasonic cleaning and wiping with anhydrous ethanol;

[0008] S2. Based on the pre-processed conductive steel roller and according to the initial roughness and target roughness of the conductive steel roller, set the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance and scanning overlap rate.

[0009] S3. Based on the above-mentioned online laser grinding, while the steel roller rotates, the laser processing head spirally scans the surface of the steel roller along the axial and radial directions at a set feed speed and step distance. The laser removes surface peaks and gradually reduces the surface roughness to the target value.

[0010] S4. Real-time monitoring and feedback: Measure the surface roughness of the steel roller during the laser grinding process, calculate the error based on the measured surface roughness of the steel roller, and adjust the laser processing parameters accordingly.

[0011] S5. Post-processing: After the steel roller is ground, the surface of the conductive steel roller is sprayed with pure water for cleaning and then dried. The surface roughness, cylindricity, and copper foil thickness deviation of the conductive steel roller are then tested.

[0012] Preferably, in step S1, the pretreatment of the conductive steel roller surface includes:

[0013] The conductive steel roller was placed in an ultrasonic cleaning tank and cleaned for 5 minutes at room temperature using ultrasonic waves at a frequency of 40kHz and a power of 200W.

[0014] After cleaning, wipe the roller from the roller end to the roller body in a spiral direction using anhydrous ethanol with a water content of ≤0.1wt%.

[0015] After wiping with ethanol, use dry compressed air at 0.6 MPa to blow evenly from the inside out until there is no visible liquid film on the surface.

[0016] Preferably, in step S2, setting the laser average power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance, and scanning overlap rate includes:

[0017] The initial roughness of the roller surface is measured using a contact roughness tester, and the machining allowance is determined in conjunction with the target roughness given in the process specification.

[0018] Based on the machining allowance and material thermophysical parameters, the average laser power was selected as 100W-500W by referring to a table;

[0019] Based on the processing depth requirements, the pulse frequency is set to 20Hz-100Hz, and the pulse width is set to 50ns-200ns.

[0020] Based on the required removal volume and spot overlap rate, determine the spot diameter as 0.1mm-5mm, the radial feed step, and the scanning overlap rate as 50%-90%.

[0021] Based on the roller length and mechanical rigidity, the axial feed speed is set to 0.5mm / s-5mm / s.

[0022] Preferably, determining the machining allowance based on the target roughness given in the process specification includes:

[0023] Based on the quality requirements of the copper foil production process, the required range of steel roller surface roughness is obtained from the process specifications. This range corresponds to the adhesion and release performance requirements of the copper foil.

[0024] The difference between the measured initial roughness of the roller surface and the target roughness is the actual machining allowance that needs to be removed. This machining allowance is used for the initial setting of subsequent laser processing parameters.

[0025] Preferably, in step S3, the laser processing head helically scans the surface of the steel roller along the axial and radial directions at a set feed speed and step distance, including:

[0026] Under the coordination of the CNC system, the conductive steel roller rotates at a constant speed, the speed range of which is determined according to the selected processing parameters, and the laser processing head moves at a constant speed along the length of the roller body at a preset axial feed speed.

[0027] After completing one revolution, the circumferential offset of the laser beam is controlled by the radial feed step, so that it covers the entire roller surface in a spiral pattern; the scanning mode can be progressively advanced layer by layer according to the change in surface roughness.

[0028] Preferably, controlling the circumferential offset of the laser beam through the radial feed step includes:

[0029] Based on the relationship between the spot diameter and the required overlap rate, the radial feed step is selected to ensure that the energy overlap between adjacent scanning trajectories meets the design requirements.

[0030] After each axial movement is completed, the CNC system drives the laser processing head to move radially according to the radial feed step, thereby calibrating the starting position of the next scan.

[0031] Preferably, in step S4, calculating the error and adjusting the laser processing parameters based on the measured surface roughness of the steel roll includes:

[0032] After the laser processing head completes a section of axial scanning, an online contact roughness measuring instrument is used to perform multi-point measurements on the roller surface. The measurement points are evenly distributed along the axial and circumferential directions of the roller body to obtain the spatial distribution data of the current surface roughness.

[0033] The spatial distribution data of the roughness is transmitted to the control system, and the deviation between the current roughness and the target roughness is calculated in each measurement cycle according to the proportional-integral control algorithm.

[0034] Based on the deviation value, the average laser power is dynamically adjusted according to a pre-set adjustment strategy to match the energy input of the subsequent helical scan with the processing requirements.

[0035] Preferably, the dynamic adjustment of the average laser power includes:

[0036] Based on the calculated roughness deviation value, the average laser power is adjusted according to the predetermined increment and decrement step size to match the energy input with the processing requirements;

[0037] Dynamic adjustments are made after each measurement cycle, which can be preset by the PLC to ensure that the power adjustment and monitoring frequency remain synchronized during continuous spiral scanning.

[0038] Preferably, in step S5, detecting the surface roughness, cylindricity, and copper foil thickness deviation of the conductive steel roller includes:

[0039] The roughness parameters are obtained by using a laser scanning confocal profilometer to perform profile scanning on at least three sections parallel to the axial direction on the roller surface that has been sprayed cleaned and blown dry.

[0040] The conductive steel roller is mounted on the fixture of a coordinate measuring machine. Cylindricity measurements are performed at four equally divided angle positions at the end, middle and near the tail of the roller body. The cylindricity error of the entire cross section is calculated based on the measurement results.

[0041] In the same unit environment, an actuated online thickness measuring instrument is used to measure the rolled copper foil sample at multiple points. The measurement area covers different positions in the width direction of the copper foil. The measured thickness data is compared with the process standard to determine the thickness deviation range.

[0042] The present invention also provides a surface treatment system for a conductive steel roller for copper foil, comprising:

[0043] The pretreatment module is used to place the conductive steel roller to be processed in an ultrasonic cleaning tank and perform pretreatment, which includes ultrasonic cleaning, wiping with anhydrous ethanol and drying with compressed air.

[0044] The parameter setting module calculates and sets the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance, and scanning overlap rate based on the initial roughness of the pre-treated conductive steel roller and the target roughness given in the process specification.

[0045] The laser polishing module, based on the aforementioned settings, enables the conductive steel roller to rotate at a set speed and drives the laser processing head to perform axial and radial helical scanning according to the aforementioned parameters;

[0046] The online monitoring module collects surface roughness data of the conductive steel roller in real time during the laser grinding process based on the settings, and transmits the data to the control system to calculate the deviation and issue parameter adjustment instructions.

[0047] The post-processing module is used to finally clean the ground conductive steel roller with pure water spray, dry it with compressed air, and control the coordinate measuring machine and online thickness measuring instrument to detect the cylindricity and copper foil thickness deviation, respectively.

[0048] This invention provides a surface treatment method for conductive steel rollers used with copper foil. It has the following beneficial effects:

[0049] 1. This invention employs a laser grinding combined with real-time monitoring and feedback technology, achieving precise control and automated adjustment of the surface roughness of steel rollers. Compared to traditional mechanical grinding methods in the prior art, this invention can adjust laser parameters in real time, effectively reducing manual intervention and ensuring the efficiency and consistency of each production stage, thereby improving the surface quality of the product.

[0050] 2. This invention introduces a spiral scanning path design in the online laser polishing process, successfully solving the surface unevenness problem in traditional scanning methods. Compared with the linear or segmented scanning methods commonly used in the prior art, the spiral scanning path of this solution not only improves the coverage of the roller surface treatment, but also effectively avoids leaving processing marks on the surface, making the steel roller surface smoother and meeting higher precision requirements.

[0051] 3. This invention employs a pure water spray cleaning and drying system for post-treatment, improving the cleanliness and stability of the steel roller surface treatment. Compared to existing methods that rely solely on manual cleaning, the automated cleaning and drying process of this invention not only improves efficiency but also avoids surface residue problems caused by incomplete cleaning, effectively ensuring the accuracy of subsequent testing.

[0052] 4. This invention combines laser grinding and precision testing technologies to comprehensively improve the controllability and consistency of steel roller surface quality. Unlike traditional technologies that rely on single-dimensional testing methods for surface roughness and cylindricity, this invention ensures precise adjustment at each stage through multi-dimensional real-time data feedback. This overcomes the shortcomings of traditional methods that cannot simultaneously address multiple quality indicators, effectively improving the uniformity and stability of copper foil adhesion. Attached Figure Description

[0053] Figure 1 This is a schematic diagram of the method flow of the present invention;

[0054] Figure 2 This is a schematic diagram of the rotation direction of the conductive steel roller of the present invention;

[0055] Figure 3This is a schematic diagram of the movement of the laser device of the present invention;

[0056] Figure 4 This is a system architecture diagram of the present invention. Detailed Implementation

[0057] The technical solutions in 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.

[0058] Please see the appendix Figure 1 - Appendix Figure 3 This invention provides a surface treatment method for conductive steel rollers used for copper foil, comprising the following steps:

[0059] S1. Pre-treat the surface of the conductive steel roller, the pre-treatment including ultrasonic cleaning and wiping with anhydrous ethanol;

[0060] In the surface treatment method for conductive steel rollers used for copper foil, a thorough and standardized pretreatment of the roller surface is typically required before the laser grinding step to remove impurities such as oil, particles, and liquid films, ensuring the uniformity of subsequent laser energy transfer and the stability of the processing effect. Generally, the pretreatment process follows the confirmation of process parameters and preliminary equipment preparation, and is carried out at the beginning of the processing steps. This step not only ensures the cleanliness of the roller surface but also lays a good foundation for subsequent laser spiral scanning, energy superposition, and roughness reduction.

[0061] Alternatively, pretreatment can be performed by combining ultrasonic cleaning, anhydrous ethanol wiping, and compressed air purging. In one possible implementation, the efficiency and uniformity of the pretreatment stage can be further improved by appropriately setting the ultrasonic frequency, power, and time parameters. Specifically, this step will be described in detail below with reference to the technical solution of the present invention and existing experimental data.

[0062] The conductive steel roller is removed from the production unit and placed in a pre-prepared ultrasonic cleaning tank. The cleaning solution is deionized water or high-purity water. The frequency of the ultrasonic cleaning tank is set as follows:

[0063] f us =40kHz;

[0064] In the formula, f us This indicates the ultrasonic frequency, measured in kilohertz (kHz). The ultrasonic power is set as follows:

[0065] P us =200W;

[0066] In the formula, P us This indicates ultrasonic power, measured in watts. The cleaning time is set as follows:

[0067] t us =5min;

[0068] In the formula, t us The duration of the cleaning process is indicated in minutes. During the cleaning process, the water temperature should be kept at room temperature to avoid overheating and causing dry spots on the liquid film. After the ultrasonic cleaning, the roller surface is visibly free of noticeable oil and adhering particles, exhibiting a uniformly moistened state.

[0069] Generally, after ultrasonic cleaning, the surface should be wiped immediately with anhydrous ethanol to prevent uneven spots from forming after the residual water film dries. Use anhydrous ethanol with a purity of not less than 99.9% and a water content of less than or equal to 0.1 wt%. Wipe in a spiral pattern, evenly covering the surface from the roller end to the roller tail. The wiping cloth used should be a lint-free, non-shedding cleaning cloth, and the width of each coverage should be no less than twice the diameter of the laser spot to ensure that the subsequent laser path is not contaminated.

[0070] In some embodiments, to facilitate subsequent process parameter setting and machining allowance calculation, the initial roughness Ra0 can be measured and recorded immediately after pretreatment using a contact roughness meter at three evenly distributed locations on the roller surface. The roughness measurement value can be used as the subsequent target roughness Ra. t The calculation basis for machining allowance ΔRa is as follows:

[0071] ΔRa=Ra0-Ra t ;

[0072] In the formula, ΔRa represents the roughness difference; Ra0 represents the initial roughness; Ra t This represents the target roughness.

[0073] In one possible implementation, the recording and inspection during the pre-processing stage can be combined with barcode scanning and electronic recording systems to establish a roll surface condition archive, so as to track the processing history of each roll over a long period of time.

[0074] Specifically, after pretreatment, the steel roller should be immediately placed on a dust-free storage rack. It should only proceed to the next laser grinding process after subsequent process parameter input and equipment inspection. At this point, the surface condition should meet the following requirements: no oil stains, no liquid film, and no particles visible to the naked eye; stable and uniform roughness measurement data; and air humidity below the specified value.

[0075] S2. Based on the pre-processed conductive steel roller and according to the initial roughness and target roughness of the conductive steel roller, set the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance and scanning overlap rate.

[0076] After pretreatment of the conductive steel roller surface, to achieve stable and controllable processing results in subsequent laser polishing, it is necessary to rationally set various parameters of the laser system based on the actual state of the roller surface after pretreatment. Generally, this stage follows immediately after pretreatment and requires parameter input and verification before the laser processing equipment is put into operation. Alternatively, this step, based on the initial roughness value of the conductive steel roller measured after pretreatment and the target roughness specified in the process procedure, calculates the machining allowance and consults empirical parameter tables to determine the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step, and scanning overlap rate. In one possible implementation, the spot parameters and feed speed can be locally modified based on the roller length and radius of curvature to ensure processing uniformity in different areas.

[0077] In this embodiment, the initial roughness value is first measured at three uniform locations along the length of the conductive steel roller using a contact roughness tester, and the average value is taken as the initial roughness Ra0. The target roughness Ra is then determined according to the copper foil production process specifications. t Calculate the actual machining allowance ΔRa:

[0078] Generally, when ΔRa is less than 0.5 μm, a lower laser power and a higher scanning overlap rate are used to avoid excessive surface ablation; when ΔRa is greater than 0.5 μm, the power is appropriately increased and the overlap rate is reduced to ensure processing efficiency. Specifically, the average laser power P... L Based on empirical parameter tables, the selection is typically between 100W and 500W. As an alternative, if the roller material is stainless steel and ΔRa≈0.4μm, then P... L 300W was selected.

[0079] In this embodiment, the pulse frequency f p The frequency range is selected between 20Hz and 100Hz based on the required processing depth, where f p The pulse width τ represents the repetition frequency of the laser pulse per unit time, measured in Hertz (Hz). p The thermal diffusion characteristics of the corresponding materials are set to 50ns-200ns, with the unit being nanoseconds (ns).

[0080] Specifically, the spot diameter d f The range is selected between 0.1mm and 5mm, depending on the completeness of the processing area and the radius of curvature. The unit is millimeters.

[0081] In one possible implementation, the spot diameter can also be slightly dynamically adjusted during the scanning process to accommodate the local morphological differences between the two ends and the middle of the conductive steel roller.

[0082] Axial feed rate v z Considering roll length, rigidity, and equipment load capacity, a speed range of 0.5 mm / s to 5 mm / s (in millimeters per second) is selected. Radial feed step distance Δ r Matching the spot diameter and snow overlap rate, it is typically set between 0.01mm and 0.05mm, in millimeters. Scan overlap rate η o Defined as the proportion of the energy coverage area between adjacent nanotraces, typically chosen between 50% and 90%, expressed as a percentage. Overlap rate η o The following formula can be used for approximate calculation:

[0083]

[0084] In the formula, η o Δ represents the scan overlap rate. r d is the radial feed step distance; f The diameter of the focused spot.

[0085] In some embodiments, to ensure the rationality of the set parameters, the power and frequency ratio can be adjusted through preliminary research experiments, combined with the thermal properties of the roll material (such as thermal diffusivity, melting point, and specific heat capacity). Alternatively, various parameters can be fine-tuned based on real-time detection data of the roll surface to optimize subsequent processing effects, but the overall setting range should not deviate from the aforementioned range.

[0086] In one possible implementation, the parameter settings can be automatically recorded and archived during the process, forming a process parameter database to provide a reference for subsequent processing of rollers of the same specifications. Generally, after setting the parameters, the operator needs to check each value against the control panel display to ensure the input is correct before proceeding to the next laser processing step.

[0087] S3. Based on the above-mentioned online laser grinding, while the steel roller rotates, the laser processing head spirally scans the surface of the steel roller along the axial and radial directions at a set feed speed and step distance. The laser removes surface peaks and gradually reduces the surface roughness to the target value.

[0088] After pretreatment of the conductive steel roller surface and proper setting of various laser processing parameters, the online laser polishing step can be initiated. Generally, this step follows immediately after the parameter setting stage and, as the main process, removes surface peaks layer by layer and uniformly reduces roughness according to a predetermined processing allowance. Specifically, under the set parameters, the conductive steel roller rotates at a constant speed while the laser processing head moves synchronously along the axial and radial directions at a set feed rate and step distance, forming a spiral scanning trajectory on the roller surface and completing the coverage processing of the entire roller surface. Alternatively, this step uses a spiral trajectory instead of parallel or segmented scanning to ensure trajectory continuity and coverage uniformity, reducing surface streaks. In one possible implementation, real-time feedback data can be used to locally adjust the spiral trajectory to further improve processing consistency.

[0089] In this embodiment, after confirming that the roller body is stably installed and all parameters are set correctly, the servo motion control system is activated to drive the conductive steel roller to rotate. Rotational speed n r Adjusted according to a preset value, in revolutions per minute. Simultaneously, the laser processing head begins to feed along the roller axial direction at a predetermined feed speed v. z The machining head moves at a constant speed. In the radial direction, it feeds at a preset radial feed step Δ. r After each complete scan, the device moves one step in the inner diameter direction to achieve progressive advancement.

[0090] Generally, a constant processing distance is maintained between the laser processing head and the steel roller, ensuring that the laser spot is precisely focused on the roller surface. Under the coordination of the CNC system, the axial position z(t) and radial position r(t) of the laser processing head can be described by the following relationship:

[0091] z(t) = v z ·t;

[0092] r(t) = r0 - i·Δ r ;

[0093] In the formula, t is the processing time; r0 is the initial radius of the roller; i is the current radial layer number; Δ r denoted as radial feed step; z(t) represents the change in the axial position of the laser processing head; r(t) represents the change in the radial position of the laser processing head.

[0094] Specifically, the rotation of the steel roller and the axial feed of the laser processing head jointly determine the pitch and overlap rate of the helical trajectory. Scan overlap rate η oThe overlap rate is determined by a preset value to ensure sufficient energy superposition between adjacent revolutions without creating unprocessed areas. In some embodiments, the overlap rate can be set between 50% and 90%. The motion control of the laser processing head can be displayed in real time on the control interface for easy monitoring by the operator.

[0095] As an alternative, to reduce localized deformation caused by heat accumulation during processing, segmented scanning or short pauses between different radial layers can be used during the scanning process, which helps to distribute heat evenly. In one possible implementation, by changing the processing sequence or adjusting the angle of the scanning start position, the circumferential texture can be prevented from aligning with the subsequent copper foil deposition direction, thereby improving the uniformity of copper foil adhesion.

[0096] In this embodiment, as the helical scan progresses, the surface micro-peaks are gradually melted, vaporized, and remelted by the laser. The surface roughness decreases approximately linearly with the number of processing layers until it approaches or reaches the target roughness Ra. t Typically, after completing each radial scan layer, the system records the current processing layer number and the corresponding radius value r. i This is for subsequent testing and verification.

[0097] The aforementioned laser helical scanning step is closely coordinated with the subsequent real-time detection and feedback process. The control system receives roughness detection data simultaneously with the helical scanning to determine whether adjustments to parameters such as power or frequency are necessary. This seamless integration ensures that the uniformity of roughness along both the axial and circumferential directions during processing meets design requirements.

[0098] S4. Real-time monitoring and feedback: Measure the surface roughness of the steel roller during the laser grinding process, calculate the error based on the measured surface roughness of the steel roller, and adjust the laser processing parameters accordingly.

[0099] During laser polishing, real-time monitoring and feedback technology is used to continuously track changes in the surface roughness of the steel roll and adjust laser processing parameters based on these real-time measurements. This step is crucial in the entire laser polishing process, ensuring that each layer of processing accurately achieves the predetermined target roughness, thereby improving processing precision and efficiency. Typically, this monitoring process is synchronized with the real-time progress of laser scanning, forming a closed-loop feedback mechanism through integration with the laser processing system's control system.

[0100] In this embodiment, during the laser polishing process, a high-precision contact or non-contact roughness measuring instrument is used to measure the surface roughness of the steel roll in real time, and the measurement result is input into the system as a feedback signal. To accurately reflect the quality of the steel roll surface processing, roughness measurement is typically performed after a certain number of revolutions or each radial feed step, and the current roughness value Ra is recorded. measured .

[0101] In this real-time monitoring process, error calculation is essential. Based on the pre-set target roughness Ra... t Calculate the error ΔRa between the actual roughness and the target roughness:

[0102] ΔRa=Ra measured -Ra t ;

[0103] In the formula, ΔRa represents the roughness error; Ra measured Ra is the currently measured surface roughness value of the steel roll. t The target roughness.

[0104] Specifically, when the measurement error ΔRa exceeds the set allowable range, the control system will adjust the laser processing parameters based on this error. The adjustment can be made by increasing or decreasing the average laser power P. L Pulse frequency f p Pulse width τ p This is achieved through parameters such as... For example, if the measured roughness is too high, the system can automatically increase the laser power P. L′ This increases the surface removal rate and accelerates the reduction of roughness; conversely, if the roughness is too low, over-processing can be avoided by reducing the laser power or adjusting the scanning speed.

[0105] During implementation, the real-time feedback system also monitors the feed speed v of the laser processing head. z and radial feed step Δ r This is to ensure the uniformity of surface quality during processing. Generally, the feed rate v... z It will depend on the width of the processing area and the rotation speed n of the steel roller. r The system can be optimized to match the target roughness. For example, with a large error value ΔRa, the system may automatically slow down the feed rate to increase the residence time of the laser on the roller surface, thereby improving the roughness removal effect.

[0106] As an alternative, if the system detects areas with significant local roughness fluctuations on the surface, it can also choose to perform local processing on those areas, i.e., adjust the scanning trajectory or reset the spot diameter d. f This is to optimize the processing effect. Specifically, the roughness error ΔRa in a local area... local The calculation will be based on the following formula:

[0107] ΔRa local =Ra measured,local -Ra t ;

[0108] In the formula, Ra t ΔRa represents the target roughness.local Ra represents the roughness error of a local area. measured,local These are the roughness values ​​measured in a local area.

[0109] In one possible implementation, real-time data from the entire process is fed back to the operator via the industrial control system. The operator can then determine whether further adjustments to the laser processing parameters are needed based on the feedback. In some embodiments, the system can also provide a preset automatic adjustment mode. When the error exceeds a predetermined range, the system automatically adjusts the parameters and displays the adjusted results in real time.

[0110] The aforementioned technical solution ensures that the surface roughness of the steel roll remains within the target range throughout the processing, avoiding uneven surface quality or over-processing due to error accumulation. Furthermore, the real-time monitoring and feedback mechanism is closely integrated with the laser scanning control system, forming a complete closed-loop control process that not only improves processing accuracy but also optimizes production efficiency.

[0111] S5. Post-processing: After the steel roller is ground, the surface of the conductive steel roller is sprayed with pure water for cleaning and then dried. The surface roughness, cylindricity and copper foil thickness deviation of the conductive steel roller are then detected.

[0112] Generally, after laser polishing and real-time monitoring and feedback adjustments, trace amounts of processing fluid or other impurities may remain on the steel roll surface. Furthermore, thermal stress may be generated during processing, necessitating further optimization of surface quality through post-processing. As an option, post-processing includes pure water spray cleaning and drying, which not only removes residual impurities from the steel roll surface but also provides a clean surface for subsequent quality inspection. Specifically, this post-processing effectively removes residual dust, oil, and impurities from the steel roll surface, ensuring that it does not affect subsequent surface quality inspection.

[0113] In this embodiment, the post-processing step first involves cleaning the surface of the conductive steel roller using a pure water spray system. The spray nozzles of the pure water spray system evenly cover the surface of the steel roller, effectively removing residual particles and impurities through high-pressure water flow. During the cleaning process, the flow rate and pressure of the pure water can be adjusted appropriately according to the surface condition of the steel roller, typically within a pressure range of 2-5 bar. The spray angle and water flow rate are adjusted to ensure thorough cleaning of the steel roller surface. After cleaning, any residual moisture on the steel roller surface must be completely removed using a drying system to ensure the accuracy of subsequent measurements.

[0114] Specifically, the drying process uses a high-temperature dry airflow, typically within the range of 50°C to 100°C, coupled with an appropriate airflow speed, to rapidly evaporate moisture from the surface of the steel roller. Alternatively, the drying air is heated by a built-in heating element and passes through a multi-stage filtration system to remove impurities, preventing any particles or water droplets from remaining on the steel roller surface. The drying time and temperature settings are fine-tuned according to the material of the steel roller and the required surface roughness to ensure no negative impact on surface quality.

[0115] After cleaning and drying, surface quality inspection is performed. This step includes not only measuring the surface roughness of the steel roller, but also checking the cylindricity of the steel roller and the thickness deviation of the copper foil. Specifically, the surface roughness of the steel roller is measured using a high-precision roughness meter to ensure that it meets the predetermined technical standards. The roughness measurement results should match the target roughness value. If it is found to exceed the allowable error range, the system will trigger feedback to adjust the preceding processing steps.

[0116] In addition, the cylindricity of the steel roller is also an important inspection indicator in the post-processing. In some embodiments, the cylindricity of the steel roller is typically measured using a laser scanner or a coordinate measuring machine (CMM), which can accurately measure the axial and radial shape of the steel roller to ensure that it meets design requirements. If the cylindricity deviation exceeds the specified range, it may affect the subsequent copper foil adhesion quality; therefore, it must be strictly monitored and kept within the allowable error range.

[0117] As a supplement, copper foil thickness deviation detection is also an essential post-processing step. Copper foil thickness measurement is typically performed using ultrasonic measurement or a coating thickness gauge to ensure that the copper foil is uniform across the entire surface and meets the specified thickness requirements. If the test results show that the thickness deviation exceeds the allowable value, the steel roller in that area needs to be reprocessed to ensure the uniformity and quality of the copper foil.

[0118] In one possible implementation, the cleaning, drying, and subsequent inspection processes can be automated and monitored. An integrated control system automatically records the quality inspection data for each workpiece and feeds the results back to the production line for adjustment and optimization. This integrated approach not only improves inspection efficiency but also ensures precise execution at every stage of the post-processing, allowing for timely detection and correction of problems.

[0119] The surface treatment system for conductive steel rollers for copper foil described below can be referred to in correspondence with the surface treatment method for conductive steel rollers for copper foil described above.

[0120] Please see the appendix Figure 4 The present invention also provides a surface treatment system for a conductive steel roller for copper foil, comprising:

[0121] The pretreatment module is used to place the conductive steel roller to be processed in an ultrasonic cleaning tank and perform pretreatment, which includes ultrasonic cleaning, wiping with anhydrous ethanol and drying with compressed air.

[0122] The parameter setting module calculates and sets the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance, and scanning overlap rate based on the initial roughness of the pre-treated conductive steel roller and the target roughness given in the process specification.

[0123] The laser polishing module, based on the aforementioned settings, enables the conductive steel roller to rotate at a set speed and drives the laser processing head to perform axial and radial helical scanning according to the aforementioned parameters;

[0124] The online monitoring module collects surface roughness data of the conductive steel roller in real time during the laser grinding process based on the settings, and transmits the data to the control system to calculate the deviation and issue parameter adjustment instructions.

[0125] The post-processing module is used to finally clean the ground conductive steel roller with pure water spray, dry it with compressed air, and control the coordinate measuring machine and online thickness measuring instrument to detect the cylindricity and copper foil thickness deviation, respectively.

[0126] The system in this embodiment can be used to execute the above method embodiments, and its principle and technical effect are similar, so they will not be described again here.

[0127] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for surface treatment of conductive steel rollers for copper foil, characterized in that, Includes the following steps: S1. Pre-treat the surface of the conductive steel roller, the pre-treatment including ultrasonic cleaning and wiping with anhydrous ethanol; S2. Based on the pre-processed conductive steel roller and according to the initial roughness and target roughness of the conductive steel roller, set the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance and scanning overlap rate. S3. Based on the above-mentioned online laser grinding, while the steel roller rotates, the laser processing head spirally scans the surface of the steel roller along the axial and radial directions at a set feed speed and step distance. The laser removes surface peaks and gradually reduces the surface roughness to the target value. S4. Real-time monitoring and feedback: Measure the surface roughness of the steel roller during the laser grinding process, calculate the error based on the measured surface roughness of the steel roller, and adjust the laser processing parameters accordingly. S5. Post-processing: After the steel roller is ground, the surface of the conductive steel roller is sprayed with pure water for cleaning and then dried. The surface roughness, cylindricity and copper foil thickness deviation of the conductive steel roller are then detected. In step S3, the laser processing head helically scans the surface of the steel roller along the axial and radial directions at a set feed speed and step distance, including: Under the coordination of the CNC system, the conductive steel roller rotates at a constant speed, the speed range of which is determined according to the selected processing parameters. The laser processing head moves at a constant speed along the length of the roller body at a preset axial feed speed. After completing one revolution, the circumferential offset of the laser beam is controlled by the radial feed step, so that it covers the entire roller surface in a spiral pattern; the scanning mode can be progressively advanced layer by layer according to the change in surface roughness; In step S4, calculating the error and adjusting the laser processing parameters based on the measured surface roughness of the steel roll includes: After the laser processing head completes a section of axial scanning, an online contact roughness measuring instrument is used to perform multi-point measurements on the roller surface. The measurement points are evenly distributed along the axial and circumferential directions of the roller body to obtain the spatial distribution data of the current surface roughness. The spatial distribution data of the roughness is transmitted to the control system, and the deviation between the current roughness and the target roughness is calculated in each measurement cycle according to the proportional-integral control algorithm. Based on the deviation value, the average laser power is dynamically adjusted according to a pre-set adjustment strategy to match the energy input of the subsequent helical scan with the processing requirements.

2. The surface treatment method for a conductive steel roller for copper foil according to claim 1, characterized in that, In step S1, the pretreatment of the conductive steel roller surface includes: The conductive steel roller was placed in an ultrasonic cleaning tank and cleaned for 5 minutes at room temperature using ultrasonic waves at a frequency of 40kHz and a power of 200W. After cleaning, wipe the roller from the end to the roller body in a spiral direction with anhydrous ethanol with a water content of ≤0.1wt%; After wiping with ethanol, use dry compressed air at 0.6 MPa to blow evenly from the inside out until there is no visible liquid film on the surface.

3. The surface treatment method for a conductive steel roller for copper foil according to claim 1, characterized in that, In step S2, setting the laser average power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance, and scanning overlap rate includes: The initial roughness of the roller surface is measured using a contact roughness tester, and the machining allowance is determined in conjunction with the target roughness given in the process specification. Based on the machining allowance and material thermophysical parameters, the average laser power was selected as 100W-500W by referring to a table; Based on the processing depth requirements, the pulse frequency is set to 20Hz-100Hz, and the pulse width is set to 50ns-200ns. Based on the required removal volume and spot overlap rate, determine the spot diameter as 0.1mm-5mm, radial feed step distance, and scanning overlap rate as 50%-90%. Based on the roller length and mechanical rigidity, the axial feed speed is set to 0.5mm / s-5mm / s.

4. The surface treatment method for a conductive steel roller for copper foil according to claim 3, characterized in that, Determining the machining allowance based on the target roughness given in the process specification includes: Based on the quality requirements of the copper foil production process, the required range of steel roller surface roughness is obtained from the process specifications. This range corresponds to the adhesion and release performance requirements of the copper foil. The difference between the measured initial roughness of the roller surface and the target roughness is the actual machining allowance that needs to be removed. This machining allowance is used for the initial setting of subsequent laser processing parameters.

5. The surface treatment method for a conductive steel roller for copper foil according to claim 1, characterized in that, The control of the circumferential offset of the laser beam by the radial feed step includes: Based on the relationship between the spot diameter and the required overlap rate, the radial feed step is selected to ensure that the energy overlap between adjacent scanning trajectories meets the design requirements. After each axial movement is completed, the CNC system drives the laser processing head to move radially according to the radial feed step, thereby calibrating the starting position of the next scan.

6. The surface treatment method for a conductive steel roller for copper foil according to claim 1, characterized in that, The dynamic adjustment of the average laser power includes: Based on the calculated roughness deviation value, the average laser power is adjusted according to the predetermined increment and decrement step size to match the energy input with the processing requirements; Dynamic adjustments are made after each measurement cycle, which can be preset by the PLC to ensure that the power adjustment and monitoring frequency remain synchronized during continuous spiral scanning.

7. The surface treatment method for a conductive steel roller for copper foil according to claim 1, characterized in that, Step S5, detecting the surface roughness, cylindricity, and copper foil thickness deviation of the conductive steel roller includes: The roughness parameters are obtained by using a laser scanning confocal profilometer to perform profile scanning on at least three sections parallel to the axial direction on the roller surface that has been sprayed cleaned and blown dry. The conductive steel roller is mounted on the fixture of a coordinate measuring machine. Cylindricity measurements are performed at four equally divided angle positions at the end, middle and near the tail of the roller body. The cylindricity error of the entire cross section is calculated based on the measurement results. In the same unit environment, an actuated online thickness measuring instrument is used to measure the rolled copper foil sample at multiple points. The measurement area covers different positions in the width direction of the copper foil. The measured thickness data is compared with the process standard to determine the thickness deviation range.

8. A surface treatment system for a conductive steel roller for copper foil, comprising a surface treatment method for a conductive steel roller for copper foil according to any one of claims 1-7, characterized in that, include: The pretreatment module is used to place the conductive steel roller to be processed in an ultrasonic cleaning tank and perform pretreatment, which includes ultrasonic cleaning, wiping with anhydrous ethanol and drying with compressed air. The parameter setting module calculates and sets the average laser power, pulse frequency, pulse width, spot diameter, axial feed speed, radial feed step distance, and scanning overlap rate based on the initial roughness of the pre-treated conductive steel roller and the target roughness given in the process specification. The laser polishing module, based on the aforementioned settings, enables the conductive steel roller to rotate at a set speed and drives the laser processing head to perform axial and radial helical scanning according to the aforementioned parameters; The online monitoring module collects surface roughness data of the conductive steel roller in real time during the laser grinding process based on the settings, and transmits the data to the control system to calculate the deviation and issue parameter adjustment instructions. The post-processing module is used to finally clean the ground conductive steel roller with pure water spray, dry it with compressed air, and control the coordinate measuring machine and online thickness measuring instrument to detect the cylindricity and copper foil thickness deviation, respectively.

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