A low temperature rolling preparation method for metal strip
Through the combined process of low-temperature hot rolling and recrystallization annealing, the problems of high energy consumption and poor accuracy of the preparation method of hot rolling of metal plates are solved, the process flow is simplified, the mechanical properties and dimensional accuracy of the product are improved, and the thinner ones are met Production demand for strips.
Patent Information
- Application Number
- CN202410669772.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-05-28
- Publication Date
- 2025-01-03
- Estimated Expiration
- 2044-05-28
AI Technical Summary
The existing metal plate and strip hot rolling preparation method consumes high energy, has poor accuracy, does not meet the requirements, and the cold rolling process is complex and has low efficiency, resulting in poor product performance.
After low-temperature hot rolling, softening annealing is carried out, followed by multiple cold rolling and recrystallization annealing after the cold rolling is completed. The low-temperature hot rolling temperature is controlled at 500-600℃, the cold rolling temperature is room temperature, the number of cold rolling times and recrystallization annealing Temperature and time are optimized to simplify process, reduce energy consumption and improve performance.
The preparation process of metal plate and tape is simplified, energy consumption and cost are reduced, the mechanical performance and dimensional accuracy of the product are improved, crack problems caused by thermal expansion are avoided, and the production needs of thinner tapes are met.
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Figure CN118527476B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of metal plate and strip manufacturing, and in particular to a low-temperature rolling preparation method for a metal plate and strip. Background Art
[0002] When copper processing enterprises produce semi-finished or finished copper strips, their process is to first melt and cast the electrolytic copper into copper ingots, and then carry out rough rolling, fine rolling and annealing on the copper ingots. The process is complicated and has a long cycle. Among them, in the process of obtaining copper strips, the melting and casting processes are high-energy consumption and high-pollution links. Therefore, this project aims to reduce energy consumption, pollution, product costs and shorten the production cycle, and thus considers the use of a short-process direct rolling method to produce related thin strip products of electrolytic copper.
[0003] The short-process direct rolling of cathode copper to produce copper strips eliminates the melting and casting steps in the traditional copper strip processing process, thereby simplifying the process. The process method is to first directly roll and deform the industrial electrolytic copper plate, and then process it into a copper strip of the required specifications through multiple rolling passes.
[0004] In the metal sheet and strip processing industry, rolling is a common preparation method. Metal materials are widely used in various industrial fields because of their excellent thermal conductivity and deformation resistance. However, traditional rolling methods usually need to be carried out at higher temperatures, which not only increases energy consumption, but also places high demands on equipment; in addition, high-temperature rolling (hot rolling) may also cause problems such as oxidation, deformation, and internal cracks in the metal sheet and strip. There are also problems such as poor dimensional accuracy and difficulty in ensuring the surface quality of the metal sheet and strip, which affects the quality and performance of the product. High-temperature rolling cannot produce thinner strips and cannot meet the requirements of some industries.
[0005] In order to solve the above problems, some technologies use cold rolling to process metal strips. Cold rolling can process metal strips at a lower temperature, avoiding the disadvantages of high-temperature calendering. However, the cold rolling process also has some unavoidable disadvantages. For example, the processing temperature of cold rolling is low, the calendering time is relatively long, and the production efficiency is low; the reduction rate is low, and multiple cold rolling passes are required, which also increases costs; in addition, the products obtained by cold rolling also have poor elasticity, high hardness, and poor machining performance. Although multiple annealing treatments can avoid the above problems, it will lengthen the metal strip preparation process and complicate the process.
[0006] Therefore, how to provide a low-temperature rolling preparation method for metal sheets and strips, reduce the processing temperature of the metal sheets and strips, reduce the preparation cost, and improve the comprehensive performance of the metal sheets and strips is a difficult problem that needs to be solved urgently in this field. Summary of the invention
[0007] In view of this, the present invention provides a low-temperature rolling preparation method for metal plates and strips to solve the problems of high energy consumption, poor precision, and thickness that does not meet the requirements in the existing hot rolling preparation method for metal plates and strips, while solving the problems of complex process and low efficiency in cold rolling treatment.
[0008] In order to achieve the above object, the present invention adopts the following technical solution:
[0009] A low temperature rolling preparation method for a metal strip comprises the following steps:
[0010] 1) performing low temperature hot rolling on the metal strip blank, and performing softening annealing after the low temperature hot rolling is completed;
[0011] 2) performing multiple cold rolling on the metal strip blank obtained after the softening annealing in step 1), and performing recrystallization annealing after the cold rolling to obtain the metal strip;
[0012] The processing temperature of the low temperature hot rolling in the step 1) is 500-600°C.
[0013] Preferably, in the step 1), the rolling speed of the low temperature hot rolling is 0.1 to 0.8 m / s, and the thickness of the metal strip blank after the low temperature hot rolling is 1.8 to 5 mm.
[0014] Preferably, the softening annealing temperature is 280-350° C., and the softening annealing time is 0.2-0.6 h.
[0015] Preferably, the metal sheet strip blank further includes a grinding operation after soft annealing.
[0016] Preferably, the cold rolling temperature in step 2) is room temperature, and the rolling speed is 8 to 12 m / min.
[0017] Preferably, the cold rolling is performed 3 to 6 times.
[0018] Preferably, the temperature of the recrystallization annealing is 550-650° C., and the time of the recrystallization annealing is 1.5-2 h.
[0019] Preferably, the thickness of the metal strip is 0.5-4 mm.
[0020] Preferably, the metal sheet strip blank comprises a cathode copper plate.
[0021] It can be seen from the above technical solutions that, compared with the prior art, the present invention has the following beneficial effects:
[0022] 1. The present invention firstly rolls the metal strip blank by low temperature hot rolling to quickly reduce the thickness of the metal strip blank; after the low temperature hot rolling is completed, cold rolling and post-processing operations are performed to obtain the metal strip. The processing method disclosed in the present invention can greatly simplify the preparation process, improve the rolling efficiency, and reduce the processing temperature during the rolling process, reduce energy consumption, and thus reduce the preparation cost of the metal strip;
[0023] 2. The low-temperature hot rolling treatment temperature disclosed in the present invention is low, and the temperature difference with the metal sheet and strip blank is small, which can alleviate the difference in thermal expansion coefficients of various parts caused by uneven heat and cold to a certain extent, reduce thermal stress, and avoid the generation of micro cracks; at the same time, it can also reduce the treatment temperature and reduce costs; the softening annealing process can improve the performance of the metal sheet and strip blank, and can make the metal sheet and strip blank more conducive to processing, which is convenient for subsequent cold rolling process;
[0024] 3. The total number of cold rolling times in the process disclosed by the present invention is relatively small, and no additional annealing is required during the cold rolling times, thereby simplifying the cold rolling operation. The present invention also provides a recrystallization annealing process after the cold rolling to allow the deformed grains to recrystallize into uniform grains, thereby improving the toughness, strength and hardness of the metal plate and strip, and improving its mechanical properties to meet the corresponding requirements of the application field. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.
[0026] Figure 1 is the microstructure diagram of the copper strip blank, among which, Figure 1 a in the figure is the grain boundary diagram, Figure 1 b in the figure is the recrystallization diagram;
[0027] Figure 2 The microstructure diagram of the copper strip blank with 50% deformation, where: Figure 2 a in the figure is the grain boundary diagram, Figure 2 b in the figure is the recrystallization diagram;
[0028] Figure 3 The microstructure diagram of the copper strip blank with 70% deformation, among which, Figure 3 a in the figure is the grain boundary diagram, Figure 3 b in the figure is the recrystallization diagram;
[0029] Figure 4 The microstructure diagram of the copper strip blank with 90% deformation, where: Figure 4a in the figure is the grain boundary diagram, Figure 4 Figure b is the recrystallization diagram. DETAILED DESCRIPTION
[0030] The present invention provides a low-temperature rolling preparation method for a metal strip, comprising the following steps:
[0031] 1) performing low temperature hot rolling on the metal strip blank, and performing softening annealing after the low temperature hot rolling is completed;
[0032] 2) performing multiple cold rolling on the metal strip blank obtained after the softening annealing in step 1), and performing recrystallization annealing after the cold rolling to obtain the metal strip;
[0033] In the step 1), the processing temperature of the low temperature hot rolling is 500-600°C, specifically 520°C, 540°C, 550°C, 560°C, 580°C, or 600°C.
[0034] In the present invention, the metal plate and strip blanks are subjected to pretreatment operations of grinding and polishing as well as removing the surface oxide film before low temperature hot rolling.
[0035] In the present invention, the rolling speed of the low-temperature hot rolling in the step 1) is 0.1-0.8 m / s, specifically 0.2 m / s, 0.3 m / s, 0.4 m / s, 0.5 m / s, 0.6 m / s, and 0.7 m / s; the thickness of the metal plate and strip blank after low-temperature hot rolling is 1.8-5 mm, specifically 2 mm, 2.2 mm, 2.5 mm, 2.8 mm, 3 mm, 3.2 mm, 3.5 mm, 3.8 mm, 4 mm, 4.2 mm, 4.5 mm, and 4.8 mm.
[0036] In the present invention, the low-temperature hot rolling pass can be single or multiple times, and there are no excessive requirements on the thickness of the metal plate and strip blank, which is preferably 10 to 50 mm, specifically 12 mm, 15 mm, 20 mm, 30 mm, and 40 mm.
[0037] In the present invention, when the low temperature hot rolling passes are multiple times, preferably the first pass is blanking with a deformation of 50%, and the subsequent deformation is 10% each time, preferably until the cumulative deformation reaches 90%.
[0038] In the present invention, the softening annealing temperature is 280-350°C, specifically 290°C, 300°C, 310°C, 320°C, 340°C; the softening annealing time is 0.2-0.6h, specifically 0.3h, 0.4h, 0.5h.
[0039] In the present invention, the metal sheet strip blank further includes a grinding operation after being softened and annealed.
[0040] In the present invention, the grinding operation can remove the oxide scale on the surface and can also grind away the impurities on the surface of the metal plate strip blank to make it smoother.
[0041] In the present invention, the cold rolling temperature in step 2) is room temperature, and the rolling speed is 8 to 12 m / min, specifically 8.5 m / min, 9 m / min, 9.5 m / min, 10 m / min, 10.5 m / min, 11 m / min, and 11.5 m / min.
[0042] In the present invention, the number of cold rolling is 3 to 6 times, specifically 3 times, 4 times, 5 times, or 6 times.
[0043] In the present invention, the recrystallization annealing temperature is 550-650°C, specifically 560°C, 580°C, 600°C, 620°C, 640°C; the recrystallization annealing time is 1.5-2h, specifically 1.6h, 1.7h, 1.8h, 1.9h.
[0044] In the present invention, the thickness of the metal strip is 0.5-4 mm, specifically 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, or 4 mm.
[0045] In the present invention, the metal sheet strip blank comprises a cathode copper plate, and the cathode copper plate is obtained by electrolysis.
[0046] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0047] Example 1
[0048] Copper strip blanks (electrolytic cathode copper plates, purity: 99.99%) were selected, polished and the surface oxide film was removed, and then the blanks were heated to 600°C for multiple low-temperature hot rolling (the first deformation was 50%, and the subsequent deformation was 10%), and the hot rolling speed was controlled to 0.3m / s to obtain copper strip blanks with a thickness of 5mm; after hot rolling, softening annealing was performed, and the softening annealing temperature was controlled to 300°C for 0.5h; after cooling, cold rolling was performed, and the rolling speed was controlled to 10m / min, and repeated 4 times to obtain a copper strip with a thickness of 0.5mm; then the obtained copper strip was recrystallized annealed at 580°C for 1.5h (surface grinding and pickling to remove the surface oxide film) to obtain a copper strip product.
[0049] The BC diagram, recrystallization diagram and grain boundary diagram of the copper strip blank, 50% deformation, 70% deformation and 90% deformation were tested respectively, corresponding to Figures 1 to 4 .pass Figures 1 to 4 It can be seen that under the influence of temperature and deformation at 600℃, electrolytic copper quickly shows dynamic recovery and dynamic recrystallization. When the cumulative deformation increases to 70%, the grains formed by dynamic recovery and recrystallization have completely replaced the original deformed grains. This shows that in the low-temperature hot rolling process, dynamic recovery and recrystallization play a leading role in the initial stage, and as the rolling deformation increases, the work hardening phenomenon caused by deformation becomes more obvious. At 90%, most of the grains are deformed grains, which contribute to the increase of strength and hardness.
[0050] Example 2
[0051] Copper strip blanks (electrolytic cathode copper plates, purity: 99.99%) were selected, polished and the surface oxide film was removed, and then the blanks were heated to 580°C for multiple low-temperature hot rolling (the first deformation was 50%, and the subsequent deformation was 10%), and the hot rolling speed was controlled to 0.5m / s to obtain copper strip blanks with a thickness of 5mm; after hot rolling, softening annealing was performed, and the softening annealing temperature was controlled to 300°C for 0.6h; after cooling, cold rolling was performed, and the rolling speed was controlled to 12m / min, and repeated 5 times to obtain a copper strip with a thickness of 2mm; then the obtained copper strip was recrystallized annealed at 550°C for 1.8h (surface grinding and pickling to remove the surface oxide film) to obtain copper strip products.
[0052] Example 3
[0053] Copper strip blanks (electrolytic cathode copper plates, purity: 99.99%) were selected, polished and the surface oxide film was removed, and then the blanks were heated to 550°C for multiple low-temperature hot rolling (the first deformation was 50%, and the subsequent deformation was 10%), and the hot rolling speed was controlled to 0.8m / s to obtain copper strip blanks with a thickness of 5mm; after hot rolling, softening annealing was performed, and the softening annealing temperature was controlled to 300°C for 0.2h; after cooling, cold rolling was performed, and the rolling speed was controlled to 8m / min, and repeated 4 times to obtain a copper strip with a thickness of 2mm; then the obtained copper strip was recrystallized annealed at 600°C for 2h (surface grinding and pickling to remove the surface oxide film) to obtain a copper strip product.
[0054] Example 4
[0055] Copper strip blanks (electrolytic cathode copper plates, purity: 99.99%) were selected, polished and the surface oxide film was removed, and then the blanks were heated to 500°C for multiple low-temperature hot rolling (the first deformation was 50%, and the subsequent deformation was 10%), and the hot rolling speed was controlled to 0.1m / s to obtain copper strip blanks with a thickness of 2mm; after hot rolling, softening annealing was performed, and the softening annealing temperature was controlled to 280°C for 0.5h; after cooling, cold rolling was performed, and the rolling speed was controlled to 10m / min, and repeated 6 times to obtain a copper strip with a thickness of 0.5mm; then the obtained copper strip was recrystallized annealed at 600°C for 1.5h (surface grinding and pickling to remove the surface oxide film) to obtain a copper strip product.
[0056] Example 5
[0057] Copper strip blanks (electrolytic cathode copper plates, purity: 99.99%) were selected, polished and the surface oxide film was removed, and then the blanks were heated to 650°C for multiple low-temperature hot rolling (the deformation amount of the first pass was 50%, and the deformation amount of each subsequent pass was 10%), and the hot rolling speed was controlled to 0.8 m / s to obtain copper strip blanks with a thickness of 5 mm; after hot rolling, softening annealing was performed, and the softening annealing temperature was controlled to 340°C for 0.3 h; after cooling, cold rolling was performed, and the rolling speed was controlled to 8 m / min, and repeated 3 times to obtain a copper strip with a thickness of 1.5 mm; then the obtained copper strip was recrystallized annealed at 550°C for 1.5 h (surface grinding and pickling to remove the surface oxide film) to obtain a copper strip product.
[0058] Experimental Example 1
[0059] The flatness, tensile strength and elongation at break of the copper strip products prepared in Examples 1 to 3 were tested respectively, and the test results are shown in Table 1.
[0060] Flatness: GB / T 17793-2010;
[0061] Tensile strength, yield strength, elongation at break: GB / T 228.1—2021.
[0062] Table 1 Test results of relevant properties of the copper strips prepared in Examples 1 to 3
[0063]
[0064]
[0065] It can be seen from Table 1 that the copper strip prepared by the process of the present invention has high tensile strength and elongation at break, which can reflect that the product prepared by the present invention has excellent strength and toughness; at the same time, the flatness of the product obtained by the present invention is also high. In general, the present invention prepares a copper strip with good mechanical properties through a simple and low-cost process, which provides a new idea for the existing copper strip preparation process.
[0066] Experimental Example 2
[0067] The microhardness of the copper strip under different deformation amounts under the conditions of Example 1 was tested respectively (the microhardness of the sample was tested using a Wilson 1102D37 model fully automatic microhardness tester, the sample size was selected as 10 mm long × 9 mm wide, the test force was selected as 0.2 kgf, and the indenter dwell time was 12 s. In order to make the experimental results accurate and reliable, each sample was polished with sandpaper to a bright surface before the test, and each sample was tested at 16 positions in 2 rows and 8 columns on the RD×TD surface, and finally the average microhardness value of each sample was obtained.), and the test results are shown in Table 2:
[0068] Table 2 Microhardness test results
[0069]
[0070] It can be seen from Table 2 that when the deformation amount is 90%, the indentation hardness of the copper strip is significantly improved.
[0071] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0072] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A method for preparing a metal strip by low temperature rolling, characterized in that: The following steps are involved: 1) performing low temperature hot rolling on the metal strip blank, and performing softening annealing after the low temperature hot rolling is completed; 2) performing multiple cold rolling on the metal strip blank obtained after the softening annealing in step 1), and no additional annealing is required during the multiple cold rolling, and performing recrystallization annealing after the cold rolling is completed to obtain the metal strip; In the step 1), the processing temperature of the low temperature hot rolling is 500-600° C.; In the step 1), the rolling speed of the low temperature hot rolling is 0.1-0.8 m / s, and the thickness of the metal strip blank after the low temperature hot rolling is 1.8-5 mm; The softening annealing temperature is 280-350°C, and the softening annealing time is 0.2-0.6h; The cold rolling temperature in step 2) is room temperature and the rolling speed is 8-12 m / min; The recrystallization annealing temperature is 550-650°C, and the recrystallization annealing time is 1.5-2h; The thickness of the metal strip is 0.5-4 mm; The metal sheet strip blank comprises a pure cathode copper sheet.
2. The low temperature rolling preparation method of a metal strip according to claim 1, characterized in that: The metal sheet strip blank further includes a grinding operation after being softened and annealed.
3. The low temperature rolling preparation method of a metal strip according to claim 2, characterized in that: The number of cold rolling is 3 to 6 times.