Plate shape control method used in aluminum plate strip foil rolling process

Abstract

The invention provides a plate shape control method used in the rolling process of an aluminum plate strip foil, and relates to the technical field of metal material machining, and the method comprises the steps that the aluminum plate strip foil with the preset thickness is selected as a blank, and homogenization heating treatment is carried out; carrying out primary rolling; the edge area of the blank is locally heated through a heating device in the blooming process; intermediate annealing treatment is firstly carried out after primary rolling, and then cooling is carried out through a first cooling device, so that the structure is uniform, and residual stress is eliminated; performing finish rolling to obtain a finished product; and the middle area of the blank is cooled through a second cooling device in the finish rolling process. According to the method, through multi-stage temperature compensation and local cooling control, precise intervention on metal transverse fluidity is achieved, and the plate shape control precision is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of metal material processing technology, and in particular to a method for controlling the shape of aluminum sheet, strip and foil during the rolling process. Background Technology

[0002] Aluminum sheets, strips, and foils, as lightweight metallic materials, have wide applications in electronics, packaging, aerospace, and other fields. During the rolling process of aluminum sheets, strips, and foils, factors such as uneven lateral metal flow, uneven temperature distribution, and elastic deformation of the rolls can easily lead to sheet shape defects, such as edge waviness, center waviness, and unilateral warping, directly affecting the surface quality of the product and its subsequent processing performance. Traditional sheet shape control methods have the following drawbacks:

[0003] 1. Traditional methods of plate shape control mainly rely on mechanical means, such as bending roller control, intermediate roller lateral movement, and roller shape design. Although these methods can improve the plate shape to a certain extent, they are insufficient in terms of dynamic adjustment capability, response speed, and control accuracy.

[0004] 2. In recent years, some studies have attempted to introduce temperature control methods, such as overall heating or cooling of rolls and strips, but their control accuracy is limited and cannot achieve precise local temperature compensation, making it difficult to meet the shape control requirements of high-precision aluminum foil products.

[0005] 3. Some existing technologies rely on complex data algorithms and high-precision detection systems for plate shape prediction and control, resulting in complex systems, high costs, poor adaptability, and unfavorable conditions for large-scale industrial applications. Summary of the Invention

[0006] In view of the above, the present invention provides a method for controlling the shape of aluminum sheet, strip and foil during the rolling process, which aims to solve at least one of the defects pointed out in the background art.

[0007] To achieve the above objectives, the present invention provides the following technical solution:

[0008] This invention provides a method for shape control during the rolling process of aluminum sheet, strip, and foil, comprising:

[0009] Step S1: Select aluminum sheet / strip foil of predetermined thickness as blank and perform homogenization heating treatment;

[0010] Step S2: Perform initial rolling; during the initial rolling process, the edge area of ​​the billet is locally heated using a heating device;

[0011] Step S3: After initial rolling, intermediate annealing is performed first, followed by cooling through the first cooling device to achieve uniform microstructure and eliminate residual stress.

[0012] Step S4: Perform finishing rolling to obtain the finished product; during the finishing rolling process, the middle area of ​​the billet is cooled by a second cooling device.

[0013] In some embodiments of the present invention, step S1 includes:

[0014] Aluminum sheet, strip, or foil with a thickness of 0.8mm to 2.5mm is selected as the blank material and subjected to homogenization heating treatment. The heating temperature is controlled at 350℃ to 420℃, and the holding time is not less than 3 hours.

[0015] In some embodiments of the present invention, step S2 includes:

[0016] A four-roll reversible rolling mill was used for initial rolling, with the rolling temperature set at 360℃~400℃, the reduction controlled at 30%~40%, and the rolling speed at 2.0m / s~3.5m / s;

[0017] During the initial rolling process, the edge area of ​​the billet is locally heated by a heating device with a heating power of 15kW / m to 25kW / m;

[0018] The edge region accounts for 10% to 20% of the width of the billet.

[0019] In some embodiments of the present invention, step S3 includes:

[0020] After initial rolling, intermediate annealing is performed first, with the temperature controlled at 380℃~450℃ and the holding time not less than 4 hours; then, the temperature is cooled to 180℃~250℃ by air cooling through the first cooling device, with the cooling rate controlled at 8℃ / min~15℃ / min.

[0021] In some embodiments of the present invention, step S4 includes:

[0022] The finished product is obtained by finishing rolling using a six-roll CVC mill.

[0023] The six-roll CVC mill is set with an inlet temperature of 200℃~280℃, a reduction of 25%~35%, and a rolling speed of 3.5m / s~5.0m / s;

[0024] During the finishing rolling process, the middle region of the billet is cooled by a second cooling device, with the cooling intensity controlled at 0.8℃ / s to 2.0℃ / s;

[0025] The central region accounts for 60% to 80% of the width of the billet.

[0026] In some embodiments of the present invention, the second cooling device includes local cooling nozzles arranged in front of a six-roll CVC mill.

[0027] In some embodiments of the present invention, it further includes:

[0028] Step S5: After finishing rolling, the quality inspection data of the finished product is detected in real time by an online detection device.

[0029] In some embodiments of the present invention, the quality inspection data includes: plate straightness, transverse thickness difference, and surface roughness.

[0030] In some embodiments of the present invention, it further includes:

[0031] Step S6: The control system continuously compares the quality inspection data with the predetermined quality indicators, generates a corresponding deviation signal, and outputs control commands to the heating device, the first cooling device, and the second cooling device according to the deviation signal.

[0032] In some embodiments of the present invention, the predetermined quality index includes:

[0033] Plate straightness < ±8 I-units;

[0034] Lateral thickness difference ≤ ±1.5μm;

[0035] Surface roughness Ra≤0.08μm.

[0036] The embodiments of the present invention have at least the following advantages or beneficial effects:

[0037] 1. High process control precision: Through multi-stage temperature compensation and local cooling control, precise intervention in the lateral flow of metal is achieved, significantly improving the precision of plate shape control.

[0038] 2. Strong process adaptability: It is suitable for rolling aluminum sheets, strips and foils of different thicknesses and specifications, and is especially suitable for the production of high-precision, thin-specification aluminum foil products.

[0039] 3. Energy saving and environmental protection: By using local heating and cooling methods, overall energy consumption is reduced, which is in line with the trend of green manufacturing development.

[0040] Other features and advantages of the present invention will be set forth in the following description. Detailed Implementation

[0041] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of the embodiments of the invention.

[0042] This application provides a method for shape control during the rolling process of aluminum sheet, strip, and foil, comprising the following steps:

[0043] Step S1: Select aluminum sheet / strip foil of predetermined thickness as blank and perform homogenization heating treatment to improve metal plasticity and reduce deformation resistance.

[0044] Step S2: Perform initial rolling; during the initial rolling process, the edge area of ​​the billet is locally heated by a heating device to compensate for the temperature drop in the edge area and enhance the plastic flow capacity of the edge area.

[0045] Step S3: After initial rolling, intermediate annealing is performed first, followed by cooling through the first cooling device to achieve uniform microstructure and eliminate residual stress.

[0046] Step S4: Perform finishing rolling to obtain the finished product; during the finishing rolling process, the middle area of ​​the billet is cooled by the second cooling device to suppress excessive plastic deformation in the middle area and balance the transverse flow.

[0047] Step S5: After finishing rolling, the quality inspection data of the finished product is detected in real time by an online detection device. The quality inspection data includes: plate straightness, transverse thickness difference, surface roughness, and other data.

[0048] Step S6: The control system continuously compares the quality inspection data with the predetermined quality indicators, generates a corresponding deviation signal, and outputs control commands to the heating device, the first cooling device and the second cooling device according to the deviation signal, automatically and dynamically adjusting the heating power and cooling intensity to form a closed-loop control.

[0049] The predetermined quality indicators include:

[0050] Plate straightness < ±8 I-units;

[0051] Lateral thickness difference ≤ ±1.5μm;

[0052] Surface roughness Ra≤0.08μm.

[0053] The above method has at least the following beneficial effects:

[0054] I. High process control precision: Through multi-stage temperature compensation and local cooling control, precise intervention in the lateral flow of metal is achieved, significantly improving the precision of plate shape control.

[0055] II. Strong process adaptability: It is suitable for rolling aluminum sheets, strips and foils of different thicknesses and specifications, and is especially suitable for the production of high-precision, thin-specification aluminum foil products.

[0056] Third, energy saving and environmental protection: By using local heating and cooling methods, the overall energy consumption is reduced, which is in line with the trend of green manufacturing development.

[0057] Fourth, low equipment dependence: It does not rely on complex big data algorithms and high-cost detection systems. Effective closed-loop control can be achieved by setting process parameters, which has good industrial promotion value.

[0058] The following will provide examples illustrating specific implementation methods of this application.

[0059] Example 1

[0060] Step S1: Select aluminum sheet / strip foil with a predetermined thickness of 0.8mm to 2.5mm as the blank, and perform homogenization heating treatment. The heating temperature is controlled at 350℃ to 420℃, and the holding time is not less than 3 hours, in order to improve the plasticity of the metal and reduce the deformation resistance.

[0061] Step S2: Use a four-roll reversible rolling mill for initial rolling, set the rolling temperature to 360℃~400℃, control the reduction (referring to the absolute dimensional change of the workpiece in the height (thickness) direction by the rolls) to 30%~40%, and the rolling speed to 2.0m / s~3.5m / s;

[0062] During the initial rolling process, the edge area of ​​the billet is locally heated by a heating device with a heating power of 15kW / m to 25kW / m to compensate for the temperature drop in the edge area and enhance the plastic flow capacity of the edge area.

[0063] The edge region accounts for 10% to 20% of the width of the billet.

[0064] Step S3: After the initial rolling, intermediate annealing is performed. The temperature of the intermediate annealing is controlled at 380℃~450℃, and the holding time is not less than 4 hours. Then, the temperature is cooled to 180℃~250℃ by air cooling through the first cooling device, and the cooling rate is controlled at 8℃ / min~15℃ / min to achieve uniform structure and eliminate residual stress.

[0065] Step S4: Use a six-roll CVC mill for finishing rolling to obtain the finished product;

[0066] The six-roll CVC mill is set with an inlet temperature of 200℃~280℃, a reduction of 25%~35%, and a rolling speed of 3.5m / s~5.0m / s;

[0067] During the finishing rolling process, the middle region of the billet is cooled by a second cooling device, with the cooling intensity controlled at 0.8℃ / s to 2.0℃ / s, in order to suppress excessive plastic deformation in the middle region and balance transverse flowability.

[0068] The central region accounts for 60% to 80% of the width of the billet.

[0069] Step S5: After finishing rolling, the quality inspection data of the finished product is detected in real time by an online detection device. The quality inspection data includes: plate straightness, transverse thickness difference, surface roughness, and other data.

[0070] Step S6: The control system continuously compares the quality inspection data with the predetermined quality indicators, generates a corresponding deviation signal, and outputs control commands to the heating device, the first cooling device and the second cooling device according to the deviation signal, automatically and dynamically adjusting the heating power and cooling intensity to form a closed-loop control.

[0071] The predetermined quality indicators include:

[0072] Plate straightness < ±8 I-units;

[0073] Lateral thickness difference ≤ ±1.5μm;

[0074] Surface roughness Ra≤0.08μm.

[0075] In step S6, the control system executes at least one of the following adjustment strategies based on the magnitude and type of the deviation signal:

[0076] Strategy 1: When the deviation in plate flatness is large (e.g., the measured value > |9| I-unit):

[0077] If the flow is characterized by edge ripples (i.e., excessive edge extension): the control system generates instructions to reduce the power of the heating device (for the edge) (e.g., reduce by 2kW / m-5kW / m) and increase the cooling intensity of the second cooling device (for the middle) (e.g., increase by 0.1℃ / s-0.2℃ / s) to suppress edge flow and promote middle extension.

[0078] If the flow is excessively large in the middle (i.e., the central extension is too large): the control system generates instructions to increase the power of the heating device (for the edge) (e.g., increase by 2-5 kW / m) and reduce the cooling intensity of the second cooling device (for the middle) (e.g., reduce by 0.1℃ / s-0.2℃ / s) to enhance the flow in the edge and suppress the central extension.

[0079] Strategy 2: When the lateral thickness difference is large (e.g., the measured value > |1.7| μm):

[0080] If the central part is too thick (positive convexity is too large): the control system generates a command to increase the cooling intensity of the second cooling device (for the central part) (e.g., increase by 0.1℃ / s-0.2℃ / s) to reduce the convexity by suppressing the deformation of the central part;

[0081] If the edge is too thick (negative convexity is too large): the control system generates a command to increase the power of the heating device (for the edge) (e.g., increase by 2kW / m-4 kW / m) to reduce the edge thickness by enhancing the plastic flow at the edge.

[0082] Strategy 3: When the surface roughness deviation is large (e.g., detection value > 0.09 μm):

[0083] This may be related to uneven cooling or excessive cooling intensity leading to changes in the rolling lubrication state; the control system generates instructions to moderately reduce the cooling rate of the first cooling device (for cooling after intermediate annealing) (e.g., reduce by 1℃ / min-2℃ / min) and reduce the cooling intensity of the second cooling device (for finishing rolling) (e.g., reduce by 0.1℃ / s-0.2℃ / s) to stabilize the oil film thickness and lubrication conditions in the rolling zone and improve surface quality.

[0084] Example 2

[0085] Step S1: Select 1060 aluminum sheet / strip foil with a predetermined thickness of 1.5 mm and a surface roughness Ra of 0.15 μm as the blank, heat the blank to 390°C in an annealing furnace and hold for 4 hours.

[0086] Step S2

[0087] The initial rolling was carried out using a four-roll reversible rolling mill, with the rolling temperature set at 380℃, the reduction at 35%, and the rolling speed at 2.8m / s.

[0088] During the initial rolling process, heating devices such as infrared heating equipment arranged at the entrance of the four-roll reversible rolling mill are used to locally heat the edge area of ​​the billet, with a heating power of 20kW / m.

[0089] The edge region accounts for 15% of the width of the billet.

[0090] Step S3: After initial rolling, the billet is first put into an annealing furnace for intermediate annealing. The temperature of the intermediate annealing is controlled at 420℃ and the holding time is 4 hours. Then, it is cooled to 220℃ by air cooling through the first cooling device at a cooling rate of 12℃ / min.

[0091] Step S4: Use a six-roll CVC mill for finishing rolling to obtain the finished product;

[0092] The six-roll CVC mill is set with an inlet temperature of 240℃, a reduction of 30%, and a rolling speed of 4.2m / s.

[0093] During the finishing rolling process, the middle region of the billet is cooled by a second cooling device, such as local cooling nozzles arranged in front of the six-roll CVC mill, with a cooling intensity of 1.5℃ / s, in order to suppress excessive plastic deformation in the middle region and balance transverse flow.

[0094] The central region accounts for 75% of the width of the billet.

[0095] Step S5: After finishing rolling, the quality inspection data of the finished product is detected in real time by online detection devices such as X-ray plate shape detection equipment: plate straightness +4I-unit, transverse thickness difference +1.0μm, and surface roughness 0.06μm.

[0096] Step S6: The control system continuously compares the quality inspection data with the predetermined quality indicators, generates a corresponding deviation signal, and determines that the predetermined quality indicators are met based on the deviation signal, so that the heating device, the first cooling device, the second cooling device, etc. maintain the current process parameters in subsequent processing (the control system determines that the current process parameters are optimal).

[0097] The predetermined quality indicators include:

[0098] Plate straightness < ±8 I-units;

[0099] Lateral thickness difference ≤ ±1.5μm;

[0100] Surface roughness Ra≤0.08μm.

[0101] As can be seen from the above embodiments, after adopting this method, the plate shape quality of aluminum sheet and foil is significantly improved during the rolling process, the lateral flow uniformity is improved, and the finished plate shape index meets the requirements of high-precision aluminum foil products.

[0102] Finally, it should be noted that the above are merely preferred embodiments of this application and are not intended to limit this application. For those skilled in the art, this application can have various modifications and variations. Without conflict, the embodiments and features described in the embodiments of this application can be arbitrarily combined with each other. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for controlling the shape of aluminum sheet, strip, and foil during the rolling process, characterized in that, include: Step S1: Select aluminum sheet / strip foil of predetermined thickness as blank and perform homogenization heating treatment; Step S2: Perform initial rolling; During the initial rolling process, the edge area of ​​the billet is locally heated using a heating device; Step S3: After initial rolling, intermediate annealing is performed first, followed by cooling through the first cooling device to achieve uniform microstructure and eliminate residual stress. Step S4: Perform finishing rolling to obtain the finished product; during the finishing rolling process, the middle area of ​​the billet is cooled by a second cooling device.

2. The method for controlling the shape of aluminum sheet, strip, and foil during rolling according to claim 1, characterized in that, Step S1 includes: Aluminum sheet, strip, or foil with a thickness of 0.8mm to 2.5mm is selected as the blank material and subjected to homogenization heating treatment. The heating temperature is controlled at 350℃ to 420℃, and the holding time is not less than 3 hours.

3. The method for controlling the shape of aluminum sheet, strip, and foil during rolling according to claim 1, characterized in that, Step S2 includes: A four-roll reversible rolling mill was used for initial rolling, with the rolling temperature set at 360℃~400℃, the reduction controlled at 30%~40%, and the rolling speed at 2.0m / s~3.5m / s; During the initial rolling process, the edge area of ​​the billet is locally heated by a heating device with a heating power of 15kW / m to 25kW / m; The edge region accounts for 10% to 20% of the width of the billet.

4. The method for controlling the shape of aluminum sheet, strip, and foil during rolling according to claim 1, characterized in that, Step S3 includes: After initial rolling, intermediate annealing is performed first, with the temperature controlled at 380℃~450℃ and the holding time not less than 4 hours; then, the temperature is cooled to 180℃~250℃ by air cooling through the first cooling device, with the cooling rate controlled at 8℃ / min~15℃ / min.

5. The method for controlling the shape of aluminum sheet, strip, and foil during rolling according to claim 1, characterized in that, Step S4 includes: The finished product is obtained by finishing rolling using a six-roll CVC mill. The six-roll CVC mill is set with an inlet temperature of 200℃~280℃, a reduction of 25%~35%, and a rolling speed of 3.5m / s~5.0m / s; During the finishing rolling process, the middle region of the billet is cooled by a second cooling device, with the cooling intensity controlled at 0.8℃ / s to 2.0℃ / s; The central region accounts for 60% to 80% of the width of the billet.

6. The method for controlling the shape of aluminum sheet, strip, and foil during rolling process according to claim 5, characterized in that, The second cooling device includes localized cooling nozzles arranged in front of the six-roll CVC mill.

7. The method for controlling sheet shape during aluminum sheet, strip, and foil rolling process according to any one of claims 1 to 6, characterized in that, Also includes: Step S5: After finishing rolling, the quality inspection data of the finished product is detected in real time by an online detection device.

8. The method for controlling the shape of aluminum sheet, strip, and foil during rolling according to claim 7, characterized in that, The quality inspection data includes: plate straightness, transverse thickness difference, and surface roughness.

9. The method for controlling sheet shape during aluminum sheet, strip, and foil rolling process according to claim 8, characterized in that, Also includes: Step S6: The control system continuously compares the quality inspection data with the predetermined quality indicators, generates a corresponding deviation signal, and outputs control commands to the heating device, the first cooling device, and the second cooling device according to the deviation signal.

10. The method for controlling the shape of aluminum sheet, strip, and foil during rolling according to claim 9, characterized in that, The predetermined quality indicators include: Plate straightness < ±8 I-unit; Lateral thickness difference ≤ ±1.5μm; Surface roughness Ra≤0.08μm.