Preparation method of aluminum alloy plate strip foil for electric conduction

Abstract

According to the preparation method of the aluminum alloy plate strip foil for electric conduction, an obtained aluminum alloy casting is sequentially subjected to hot rolling, primary cold rolling, secondary cold rolling and foil rolling processes to finally form an aluminum alloy foil with the thickness of 1.0-1.2 mm, and machining of the foil with the small thickness is achieved while the electric conduction performance is guaranteed; through multiple cold rolling and foil rolling processes, the strength and performance of the prepared aluminum alloy foil are effectively improved, the yield is improved, and the performance is better.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy sheet, strip and foil, and in particular to a method for preparing an aluminum alloy sheet, strip and foil for conduction. Background Art

[0002] Aluminum alloy material is a multifunctional alloy with balanced properties, suitable for a variety of applications. Due to its good electrical conductivity, it can be used in fields such as power transmission and electrical conductors, and has excellent electrical conductivity; it has high strength, and through appropriate heat treatment processes, it can obtain higher strength and hardness, suitable for applications requiring higher strength; it also has good processing performance, easy to process and shape, and can be manufactured into the required shape and size through various forming processes; it also has good corrosion resistance, and its corrosion resistance can be improved through appropriate surface treatment, suitable for use in outdoor environments and corrosive media; in addition, it also has good welding performance: it can be connected through various common welding methods, which is convenient for manufacturing and assembly.

[0003] Due to the particularity of the conductive materials used, the aluminum alloy strips are required to have good conductive properties while also requiring a thinner thickness and certain strength and performance. Therefore, these have put forward higher requirements for the current conductive aluminum alloy strips and their production methods.

[0004] Based on this, there is an urgent need to provide a method for preparing aluminum alloy sheet, strip and foil for conductive use to solve the defects and shortcomings existing in the above-mentioned prior art. Summary of the invention

[0005] In order to solve the defects and shortcomings in the above-mentioned prior art, the present invention proposes a method for preparing an aluminum alloy sheet, strip or foil for conductive use.

[0006] The technical solution provided by the present invention is: A method for preparing an aluminum alloy sheet, strip or foil for electrical conduction, characterized in that it comprises the following steps: 1) Prepare raw materials: prepare raw materials according to the preset mass ratio of each element; 2) Melting: The raw materials are sent into the melting furnace for melting; 3) Refining: The melt is sent into a refining furnace for refining; 4) Degassing and slag removal: Degassing and slag removal operations are performed on the melt; 5) Casting: Cast the degassed and deslagging melt into castings; 6) Evenly heated: the casting is sent into the heating furnace to be evenly heated and kept warm; 7) Cooling: Cool the casting to room temperature after quenching; 8) Saw head milling: Saw off the heads at both ends of the casting and then mill the casting; 9) Hot rolling: hot rolling aluminum alloy castings into aluminum alloy plates; 10) Intermediate annealing: intermediate annealing of the aluminum alloy sheet after hot rolling; 11) Initial cold rolling: the aluminum alloy sheet after intermediate annealing is then initially cold rolled to a preset first thickness range; 12) Edge trimming: Edge trimming of aluminum alloy sheets during the initial cold rolling process; 13) Secondary cold rolling: the trimmed aluminum alloy sheet is then subjected to secondary cold rolling to a preset second thickness range; 14) Foil rolling: Foil rolling is performed on aluminum alloy sheets to obtain aluminum alloy foil; 15) Quenching: quenching the cold alloy foil after foil rolling; 16) Aging: The foil after quenching treatment is sent to the aging furnace; 17) Cutting: Cut the foil into finished products according to the required size; 18) Warehousing: After the finished products are inspected and found to be qualified, they are packaged and put into storage.

[0007] As a further preferred embodiment of the present invention, in step 1), the mass fraction of each element satisfies: Si: 0.30~0.48%; Fe: 0.15~0.35; Cu: 0.02~0.15%; Mn: 0.03%; Zn: 0.10; Mg: 0.5~0.75%; The balance is Al.

[0008] As a further preferred embodiment of the present invention, in the step 2), the smelting temperature is 700-720°C, and the temperature is kept for 60-80 minutes.

[0009] As a further preferred embodiment of the present invention, in the step 3), the refining temperature is 725-750° C., and the refining time is 1-2 h.

[0010] As a further preferred embodiment of the present invention, in step 4), the melt is degassed and deslaged by filling with an inert protective gas, and the inert protective gas is a mixture of at least one or more of helium, nitrogen or neon.

[0011] As a further preferred embodiment of the present invention, in step 6), the aluminum alloy casting is placed in a heating furnace, first heated to 500-520°C and kept warm for 2-4 hours, then heated to 550-580°C and kept warm for 8-10 hours, and then cooled to 520-530°C and kept warm for 2-4 hours.

[0012] As a further preferred embodiment of the present invention, in step 9), the aluminum alloy casting is subjected to 15-17 passes of rough hot rolling and three-stand hot finishing rolling to be an aluminum alloy plate with a thickness of 5 mm, the starting rolling temperature is 450-490°C, and the finishing rolling temperature is 310-330°C.

[0013] As a further preferred embodiment of the present invention, in step 10), the hot-rolled aluminum alloy sheet is sent to an annealing furnace for annealing at a temperature of 330-380° C. for 3-4 hours.

[0014] As a further preferred embodiment of the present invention, in the step 11), the aluminum alloy sheet having a thickness of 5 mm is initially cold-rolled into an aluminum alloy sheet having a first thickness range of 2-2.5 mm according to a thickness difference of 0.5-0.8 mm each time; In the step 13), the aluminum alloy sheet having a thickness of 2-2.5 mm is subjected to secondary cold rolling with a thickness difference of 0.2-0.5 mm each time to form an aluminum alloy sheet having a second thickness range of 1.5-1.8 mm; In the step 14), the aluminum alloy sheet is fed into an aluminum foil rolling mill and rolled into an aluminum alloy foil with a thickness of 1.0-1.2 mm in six passes.

[0015] As a further preferred embodiment of the present invention, in step 16), after the foil is sent into the aging furnace, the foil is wound at a temperature of 100-150°C. After the winding is completed, the temperature of the wound foil is reduced to room temperature at a cooling rate of 3-5°C / h.

[0016] Compared with the prior art, the advantages and positive effects achieved by the present invention include: 1) The present invention provides a method for preparing an aluminum alloy sheet, strip or foil for electrical conduction. The aluminum alloy sheet, strip or foil contains Si, Fe, Cu, Mn, Zn and Mg elements, which effectively improve the electrical conductivity of the obtained aluminum alloy sheet, strip or foil.

[0017] 2) The present invention provides a method for preparing an aluminum alloy sheet, strip or foil for electrical conduction, wherein the obtained aluminum alloy casting is sequentially subjected to hot rolling, primary cold rolling, secondary cold rolling and foil rolling processes, and finally formed into an aluminum alloy foil with a thickness of 1.0-1.2 mm, thereby achieving the processing of thinner foil while ensuring the electrical conductivity; at the same time, the strength and performance of the prepared aluminum alloy foil can be effectively improved through multiple cold rolling and foil rolling processes, thereby improving the yield rate and achieving better performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A process roadmap for the preparation of a conductive aluminum alloy sheet, strip or foil provided in this application. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0020] In the description of the present invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0021] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] [First embodiment] The first embodiment of the present invention provides a method for preparing an aluminum alloy sheet, strip or foil for electrical conduction, comprising the following steps: 1) Prepare raw materials: prepare raw materials according to the preset mass ratio of each element; in this embodiment, the mass fractions of each element for preparing the aluminum alloy strip foil meet the following requirements: Si: 0.30-0.48%; Fe: 0.15-0.35; Cu: 0.02-0.15%; Mn: 0.03%; Zn: 0.10; Mg: 0.5-0.75%; the balance is Al; by including Si, Fe, Cu, Mn, Zn and Mg elements in the aluminum alloy strip foil, the electrical conductivity of the obtained aluminum alloy strip foil is effectively improved; 2) Melting: The raw materials are sent into a melting furnace for melting; the melting temperature in this embodiment is 700-720°C, and the temperature is kept for 60-80 minutes; 3) Refining: The melt is sent to a refining furnace for refining to obtain a melt; the refining temperature is 725-750°C, and the refining time is 1-2 hours; preferably, an appropriate amount of inert protective gas can be introduced during the refining process to discharge pores, slag, etc. contained in the melt, thereby further improving the purity of the melt; 4) Degassing and deslagging: Degassing and deslagging operations are performed on the melt; preferably, the degassing and deslagging operations can be performed on the melt by filling it with an inert protective gas, wherein the inert protective gas is a mixture of at least one or more of helium, nitrogen or neon. 5) Casting: Cast the degassed and deslagging melt into castings; 6) Evenly heated: the casting is sent into a heating furnace for evenly heated and kept warm; in this embodiment, the specific steps of the evenly heated process include: sending the aluminum alloy casting into a heating furnace, first heating it to 500-520℃ and keeping it warm for 2-4h, then heating it to 550-580℃ and keeping it warm for 8-10h, and then cooling it to 520-530℃ and keeping it warm for 2-4h 7) Cooling: Cool the casting to room temperature after quenching; 8) Saw head milling: Saw off the heads at both ends of the casting and then mill the casting; 9) Hot rolling: hot rolling the aluminum alloy casting into aluminum alloy plates; the specific operation steps of hot rolling are: the aluminum alloy casting is subjected to 15-17 passes of rough hot rolling and three-stand hot finishing rolling to form an aluminum alloy plate with a thickness of 5mm, the starting rolling temperature is 450-490℃, and the final rolling temperature is 310-330℃; 10) Intermediate annealing: The aluminum alloy sheet after hot rolling is subjected to intermediate annealing to maintain the stable performance of the aluminum alloy sheet; specifically, the hot-rolled aluminum alloy sheet is sent to the annealing furnace for annealing at a temperature of 330-380°C and an annealing time of 3-4 hours; 11) Primary cold rolling: the aluminum alloy sheet after intermediate annealing is subjected to primary cold rolling to a preset first thickness range; the aluminum alloy sheet with a thickness of 5 mm is formed into an aluminum alloy sheet with a first thickness range of 2-2.5 mm by primary cold rolling according to a thickness difference of 0.5-0.8 mm each time; In this process, as a preference, an aluminum alloy sheet with a thickness of 5 mm can be initially cold rolled into an aluminum alloy sheet with a first thickness range of 2-2.5 mm in a manner of decreasing thickness difference, and the sheet thickness can be adjusted after each initial cold rolling. For example, an aluminum alloy sheet with a thickness of 5 mm can be initially cold rolled with thickness differences of 0.8 mm, 0.7 mm, 0.6 mm and 0.5 mm in sequence to finally be formed into an aluminum alloy sheet with a first thickness range of 2.4 mm. This arrangement is due to: on the one hand, as the cold rolling forming is gradually carried out, the thickness of the aluminum alloy sheet decreases; on the other hand ... It will gradually become difficult, so the method of decreasing the thickness difference is more conducive to the forming of the aluminum alloy sheet; at the same time, the method of decreasing the thickness difference can facilitate the exposure of possible defects and problems of the aluminum alloy sheet during the cold rolling forming process through large thickness changes in the early and middle stages, and is also conducive to the corresponding and timely adjustment of the process parameters of the cold rolling forming. The corresponding process parameters of the cold rolling forming can be adjusted accordingly according to the initial and final thickness parameters of the aluminum alloy sheet during each cold rolling forming; in addition, the method of decreasing the thickness difference is also more conducive to the uniform composition and stable performance of the aluminum alloy sheet.

[0023] 12) Edge trimming: Edge trimming of aluminum alloy sheets during the initial cold rolling process; 13) Secondary cold rolling: the trimmed aluminum alloy sheet is subjected to secondary cold rolling to a preset second thickness range; the aluminum alloy sheet having a thickness of 2-2.5 mm is subjected to secondary cold rolling according to a thickness difference of 0.2-0.5 mm each time to form an aluminum alloy sheet having a second thickness range of 1.5-1.8 mm; Similarly, in this process, as a preference, an aluminum alloy sheet with a thickness of 2-2.5 mm can be initially cold rolled into an aluminum alloy sheet with a first thickness range of 1.5-1.8 mm in a manner of decreasing thickness difference, and the sheet thickness can be adjusted after each initial cold rolling. For example, an aluminum alloy sheet with a thickness of 2.5 mm can be successively cold rolled with thickness differences of 0.5 mm, 0.3 mm and 0.2 mm to finally be formed into an aluminum alloy sheet with a second thickness range of 1.5 mm. This arrangement is because: on the one hand, as the cold rolling forming is gradually carried out, the thickness of the aluminum alloy sheet decreases. It will gradually become difficult to reduce the degree, so the method of decreasing the thickness difference is more conducive to the forming of the aluminum alloy plate; at the same time, the method of decreasing the thickness difference can facilitate the exposure of possible defects and problems of the aluminum alloy plate during the cold rolling forming process through large thickness changes in the early and middle stages, and is also conducive to the corresponding and timely adjustment of the process parameters of the cold rolling forming. The corresponding process parameters of the cold rolling forming can be adjusted accordingly according to the initial and final thickness parameters of the aluminum alloy plate during each cold rolling forming; in addition, the method of decreasing the thickness difference is also more conducive to the uniform composition and stable performance of the aluminum alloy plate.

[0024] Furthermore, the number of times the thickness difference decreases during the secondary cold rolling process should be lower than the number of times the thickness difference decreases during the primary cold rolling process. This is because, on the one hand, the secondary cold rolling is close to the final forming process of the aluminum alloy sheet, and the frequency of changes in the sheet thickness needs to be reduced as much as possible to ensure the stability of the performance of the finished product; on the other hand, the change in the thickness difference during the secondary cold rolling process is relatively low, so the adjustment accuracy of the working parameters is required to be high each time, and the adjustment process is relatively difficult. For example, for the adjustment of the spacing parameters of the rolling rollers, the more times the corresponding working parameters are adjusted according to the number of times the thickness difference decreases, the more the control process and time, and the lower the accuracy stability after adjustment. Therefore, it is necessary to reduce the frequency of changes in the sheet thickness during the secondary cold rolling process as much as possible; Correspondingly, the conveying speed of the aluminum alloy strip during the secondary cold rolling process can be set to be slower than the conveying speed of the aluminum alloy strip during the primary cold rolling process. The slower conveying speed can ensure the cold rolling process to be sufficient and comprehensive, and ensure that the thickness of the aluminum alloy strip in the overall conveying direction is uniform and stable. On the other hand, it is also conducive to the uniform composition and stable performance of the aluminum alloy strip before and after cold rolling. 14) Foil rolling: The aluminum alloy sheet is foil rolled to obtain aluminum alloy foil; the aluminum alloy sheet is sent to the aluminum foil rolling mill and rolled into aluminum alloy foil with a thickness of 1.0-1.2 mm in six passes; 15) Quenching: quenching the cold alloy foil after foil rolling; 16) Aging: After the quenching treatment, the foil is sent to the aging furnace; after the foil is sent to the aging furnace, the foil is wound at a temperature of 100-150°C. After the winding is completed, the temperature of the wound foil is reduced to room temperature at a cooling rate of 3-5°C / h; 17) Cutting: Cut the foil into finished products according to the required size; 18) Warehousing: After the finished products are inspected and found to be qualified, they are packaged and put into storage.

[0025] The obtained aluminum alloy casting is successively subjected to hot rolling, primary cold rolling, secondary cold rolling and foil rolling processes, and finally formed into an aluminum alloy foil with a thickness of 1.0-1.2mm. While ensuring the conductive performance, the processing of thinner foil is achieved; at the same time, the strength and performance of the prepared aluminum alloy foil can be effectively improved through multiple cold rolling and foil rolling processes, and the yield rate is improved, and the performance is better. It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for preparing an aluminum alloy sheet, strip or foil for electrical conduction, characterized in that: The following steps are involved: 1) Prepare raw materials: prepare raw materials according to the preset mass ratio of each element; 2) Melting: The raw materials are sent into the melting furnace for melting; 3) Refining: The melt is sent to the refining furnace for refining; 4) Degassing and slag removal: Degassing and slag removal operations are performed on the melt; 5) Casting: Cast the degassed and deslagging melt into castings; 6) Evenly heated: the casting is sent into the heating furnace to be evenly heated and kept warm; 7) Cooling: Cool the casting to room temperature after quenching; 8) Saw head milling: Saw off the heads at both ends of the casting and then mill the casting; 9) Hot rolling: hot rolling aluminum alloy castings into aluminum alloy plates; 10) Intermediate annealing: Intermediate annealing of the aluminum alloy sheet after hot rolling; 11) Initial cold rolling: the aluminum alloy sheet after intermediate annealing is then initially cold rolled to a preset first thickness range; 12) Edge trimming: Edge trimming of aluminum alloy sheets during the initial cold rolling process; 13) Secondary cold rolling: the trimmed aluminum alloy sheet is then subjected to secondary cold rolling to a preset second thickness range; 14) Foil rolling: Foil rolling is performed on aluminum alloy sheets to obtain aluminum alloy foil; 15) Quenching: quenching the cold alloy foil after foil rolling; 16) Aging: The foil after quenching treatment is sent to the aging furnace; 17) Cutting: Cut the foil into finished products according to the required size; 18) Warehousing: After the finished products are inspected and qualified, they are packaged and put into storage.

2. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In step 1), the mass fraction of each element satisfies: Si: 0.30~0.48%; Fe: 0.15~0.35; Cu: 0.02~0.15%; Mn: 0.03%; Zn: 0.10; Mg: 0.5~0.75%; The balance is Al.

3. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 2), the smelting temperature is 700-720° C. and the temperature is kept for 60-80 minutes.

4. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 3), the refining temperature is 725-750° C. and the refining time is 1-2 h.

5. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 4), the melt is degassed and deslagging is performed by injecting an inert protective gas, wherein the inert protective gas is a mixture of at least one or more of helium, nitrogen or neon.

6. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In step 6), the aluminum alloy casting is placed in a heating furnace, first heated to 500-520°C and kept warm for 2-4 hours, then heated to 550-580°C and kept warm for 8-10 hours, and then cooled to 520-530°C and kept warm for 2-4 hours.

7. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 9), the aluminum alloy casting is subjected to 15-17 passes of rough hot rolling and three-stand hot finishing rolling to be an aluminum alloy plate with a thickness of 5 mm, with a starting rolling temperature of 450-490°C and a finishing rolling temperature of 310-330°C.

8. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 10), the hot-rolled aluminum alloy sheet is sent to an annealing furnace for annealing at a temperature of 330-380° C. for 3-4 hours.

9. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 11), the aluminum alloy sheet having a thickness of 5 mm is initially cold-rolled into an aluminum alloy sheet having a first thickness range of 2-2.5 mm according to a thickness difference of 0.5-0.8 mm each time; In the step 13), the aluminum alloy sheet having a thickness of 2-2.5 mm is subjected to secondary cold rolling with a thickness difference of 0.2-0.5 mm each time to form an aluminum alloy sheet having a second thickness range of 1.5-1.8 mm; In the step 14), the aluminum alloy sheet is fed into an aluminum foil rolling mill and rolled into an aluminum alloy foil with a thickness of 1.0-1.2 mm in six passes.

10. The method for preparing a conductive aluminum alloy sheet, strip or foil according to claim 1, characterized in that: In the step 16), after the foil is sent into the aging furnace, the foil is wound at a temperature of 100-150° C. After the winding is completed, the temperature of the wound foil is reduced to room temperature at a cooling rate of 3-5° C. / h.

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