Direct rolling process of 5052-H32 aluminum alloy sheet

Abstract

The invention provides a direct rolling process of a 5052-H32 aluminum alloy sheet, which comprises the following steps: A) preparing an aluminum slab ingot from raw materials, milling the surface of the ingot, heating, and carrying out hot rolling to obtain a hot-rolled blank; and B) carrying out cold rolling on the hot-rolled blank for one pass, withdrawing and straightening, and cleaning to obtain the finished plate. After the process is optimized, the hot-rolled plate only needs to be subjected to cold rolling for one pass, the finished plate can be obtained without a low-temperature tempering procedure, the production cost is greatly saved, and the production efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of aluminum alloy processing, in particular to a direct rolling process of a 5052-H32 aluminum alloy thin plate. Background Art

[0002] 5052 aluminum alloy is a typical grade of aluminum-magnesium alloy. It has medium strength and good corrosion resistance, processing and forming properties, and welding properties. It is widely used in transportation, building decoration, mechanical and electronic appliances and other fields.

[0003] 5052 aluminum alloy is one of the most widely used alloys in the 5XXX series alloys. It is a low-Mg (Mg content is between 2.2% and 2.8%), heat-treatable non-strengthening alloy with medium strength, good weldability and corrosion resistance.

[0004] The existing production process is: melting and casting → ingot milling → heating → hot rolling → cold rolling → low-temperature tempering → straightening, cleaning and trimming → finished product. It has the problems of long process flow, high cost, need for transportation for low-temperature tempering operation and long cycle.

[0005] Therefore, it is very necessary to provide a 5052-H32 aluminum alloy sheet with a short process and stable and excellent performance. Summary of the invention

[0006] In view of this, the technical problem to be solved by the present invention is to provide a direct rolling process for 5052-H32 aluminum alloy thin plates. The hot-rolled plates of the present invention only need to be cold rolled once, and the finished plates can be obtained without going through a low-temperature tempering process, which greatly saves production costs and improves production efficiency and performance.

[0007] The present invention is based on the original production of 5052-H32 aluminum alloy export general material, and ensures the stability of material properties in the subsequent production process by clarifying the internal control range of chemical composition; at the same time, through the optimization of the rolling process, the related problems of long process flow, low production efficiency and unstable product performance in the original production process are solved.

[0008] The original production process of the trial plate of the present invention is: melting and casting → ingot milling → heating → hot rolling → cold rolling → low-temperature tempering → straightening, cleaning and trimming → finished product. This process has the problems of long process flow and unstable performance. In order to reduce production costs and improve product competitiveness, process optimization is carried out.

[0009] After process optimization, hot-rolled plates only need to be cold rolled once, and finished plates can be obtained without going through a low-temperature tempering process, which greatly saves production costs and improves production efficiency.

[0010] The present invention provides a direct rolling process for a 5052-H32 aluminum alloy sheet, comprising the following steps:

[0011] A) preparing aluminum slabs from raw materials, milling the surface of the ingots, heating, and hot rolling to obtain hot-rolled raw materials;

[0012] B) The hot rolled raw material is cold rolled once, straightened and cleaned to obtain the product.

[0013] In some specific embodiments, the raw material formula is Si≤0.12%, Fe0.2-0.35%, Cu≤0.1%, Mn≤0.1%, Mg2.5-2.8%, Cr0.15-0.3%, Zn≤0.1%, and the balance is Al.

[0014] In some specific embodiments, the milling depth of the ingot milling surface in step A) is ≥8 mm.

[0015] In some specific embodiments, the heating temperature in step A) is 480-500° C., and the insulation time is ≥3 h.

[0016] In some specific implementations, in step A), the hot rolling is performed for 13 to 19 passes; the hot rolling thickness is 24 mm to 32 mm; and the start rolling temperature is 480 to 500°C.

[0017] In some specific embodiments, the final rolling temperature of the hot rolling in step A) is 310-330°C.

[0018] In some specific implementations, the hot-rolled rough material in step A) has a thickness of 3.37 to 3.47.

[0019] In some specific implementations, the deformation amount of one cold rolling pass in step B) is 8% to 11%.

[0020] In some specific implementations, the straightening speed in step B) is ≤100 m / min, and the elongation is 0.3% to 0.5%.

[0021] The present invention provides a 5052-H32 aluminum alloy thin plate, which is prepared by the preparation method described in any one of the above technical solutions.

[0022] Compared with the prior art, the present invention provides a direct rolling process for 5052-H32 aluminum alloy thin plates, comprising the following steps: A) preparing aluminum flat ingots, milling ingots, heating, and hot rolling to obtain hot-rolled rough materials; B) cold rolling the hot-rolled rough materials once, straightening, and cleaning to obtain the finished plates. After the process is optimized, the hot-rolled plates only need to be cold rolled once, and the finished plates can be obtained without the need for low-temperature tempering, which greatly saves production costs and improves production efficiency. DETAILED DESCRIPTION

[0023] The present invention provides a direct rolling process for 5052-H32 aluminum alloy thin plates. Those skilled in the art can refer to the content of this article and appropriately improve the process parameters to achieve it. It should be particularly pointed out that all similar replacements and modifications are obvious to those skilled in the art, and they all fall within the scope of protection of the present invention. The methods and applications of the present invention have been described through preferred embodiments, and relevant personnel can obviously modify or appropriately change and combine the methods and applications of this article without departing from the content, spirit and scope of the present invention to implement and apply the technology of the present invention.

[0024] It should be understood that the expression "one or more of..." includes each of the items recited after the expression individually and in various different combinations of two or more of the recited items, unless otherwise understood from the context and usage. The expression "and / or" in combination with three or more recited items should be understood to have the same meaning, unless otherwise understood from the context.

[0025] The use of the terms "comprising", "having" or "containing", including their grammatical synonyms, should generally be understood as open and non-restrictive, for example not excluding other unrecited elements or steps, unless otherwise specifically stated or otherwise understood from the context.

[0026] In this application, the term "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0027] The present invention is based on the original production of 5052-H32 aluminum alloy export general material, and ensures the stability of material properties in the subsequent production process by clarifying the internal control range of chemical composition; at the same time, through the optimization of the rolling process, the related problems of long process flow, low production efficiency and unstable product performance in the original production process are solved.

[0028] The original production process of the trial plate of the present invention is: melting and casting → ingot milling → heating → hot rolling → cold rolling → low-temperature tempering → straightening, cleaning and trimming → finished product. This process has the problems of long process flow and unstable performance. In order to reduce production costs and improve product competitiveness, process optimization is carried out.

[0029] After process optimization, hot-rolled plates only need to be cold rolled once, and finished plates can be obtained without going through a low-temperature tempering process, which greatly saves production costs and improves production efficiency.

[0030] The present invention provides a direct rolling process for a 5052-H32 aluminum alloy sheet, comprising the following steps:

[0031] A) preparing aluminum slabs from raw materials, milling the surface of the ingots, heating, and hot rolling to obtain hot-rolled raw materials;

[0032] B) The hot rolled raw material is cold rolled once, straightened and cleaned to obtain the product.

[0033] According to the present invention, the raw material formula is Si≤0.12%, Fe0.2-0.35%, Cu≤0.1%, Mn≤0.1%, Mg2.5-2.8%, Cr0.15-0.3%, Zn≤0.1%, and the balance is Al.

[0034] The content of Fe is 0.2% to 0.35%; preferably 0.2%, 0.25%, 0.3%, 0.35%; or a range between any two of the above.

[0035] The content of Mg is 2.5-2.8%; preferably 2.5%, 2.6%, 2.7%, 2.8%; or a range between any two of the above.

[0036] The Cr content is 0.15% to 0.3%; preferably 0.15%, 0.20%, 0.25%, 0.3%; or a range between any two of the above.

[0037] The present invention controls the content of the above raw materials, especially the content of Mg, so that the tensile strength meets the requirements and the bending strength also meets the requirements.

[0038] The raw materials are used to prepare aluminum slabs. The specific process for preparing the aluminum slabs is not limited in the present invention and is well known to those skilled in the art.

[0039] The aluminum slab is subjected to ingot milling, wherein the milling depth of the ingot milling is ≥ 8 mm. No metallurgical defects are allowed on the surface after milling.

[0040] After the ingot is milled, the ingot is heated; the heating temperature is 480-500° C., and the insulation time is ≥3h.

[0041] In some specific embodiments, the heating temperature is 480° C., 490° C., 500° C., or a range between any two of the above.

[0042] The ingot is heated and then hot rolled.

[0043] In some specific embodiments, the hot rolling in step A) is performed for 13 to 19 passes; specifically, it can be 13 passes, 14 passes, 15 passes, 16 passes, 17 passes, 18 passes or 19 passes; or a range between any two of the above.

[0044] The thickness of hot rolling is 24mm~32mm;

[0045] The rolling temperature is 480-500°C.

[0046] In some specific embodiments, the thickness of rough rolling and finishing rolling is 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm; or a range between any two of the above.

[0047] Final hot rolling temperature: metal temperature 310 ~ 330 ℃, hot rolled rough material thickness 3.37 ~ 3.47 control, increase the threading speed, reduce the length of the head speed increase section, control the head thickness difference.

[0048] In some specific embodiments, the final rolling temperature of the hot rolling is specifically 310° C., 320° C. or 330° C.;

[0049] In some specific embodiments, the hot-rolled rough material has a thickness of 3.37, 3.40, 3.42, 3.45, 3.47, or a range between any two of the above.

[0050] The hot rolled raw material is cold rolled once; the deformation amount of the cold rolling once is 8% to 11%.

[0051] In some specific implementations, the deformation amount of one cold rolling pass is 8%, 9%, 10%, 11%, or a range between any two of the above.

[0052] Too much cold rolling deformation can ensure that the tensile properties of the material are qualified, but there will be cracking in the bending.

[0053] In some specific implementations, the thickness of the finished product is 3.10±0.06 mm, the thickness of the hot-rolled rough material is controlled at 3.42 mm, and the thickness of the finished product is controlled according to the lower limit to ensure that the cold deformation amount is above 8%.

[0054] After one cold rolling, the steel is straightened and cleaned.

[0055] The straightening speed of the present invention is ≤100 m / min, preferably 60-100 m / min.

[0056] The elongation is 0.3% to 0.5%; specifically, it can be 0.3%, 0.4% or 0.5%.

[0057] The present invention does not limit the specific cleaning method, which is well known to those skilled in the art. After cleaning, the aluminum coil surface is not allowed to have obvious defects such as oil stains, oil clumps, and oil strips.

[0058] The finished product is subjected to plate thickness measurement and cut after the thickness meets the requirements.

[0059] The present invention provides a 5052-H32 aluminum alloy thin plate, which is prepared by the preparation method described in any one of the above technical solutions.

[0060] The above preparation method of the present invention has been clearly described and will not be repeated here.

[0061] The present invention provides a direct rolling process for 5052-H32 aluminum alloy thin plates, comprising the following steps: A) preparing aluminum flat ingots, milling ingots, heating, and hot rolling raw materials to obtain hot-rolled rough materials; B) cold rolling the hot-rolled rough materials once, straightening, and cleaning. After the process is optimized, the hot-rolled plate only needs to be cold rolled once, and the finished plate can be obtained without the need for a low-temperature tempering process, which greatly saves production costs and improves production efficiency.

[0062] The present invention eliminates the original cold rolling-finished product annealing process and carries out short-process technology innovation of finished product thickness by adjusting alloy composition, temperature-controlled rolling and controlling cold rolling processing rate and other process optimization measures.

[0063] The present invention achieves stable and excellent performance of the finally prepared 5052-H32 aluminum alloy sheet through overall technical solutions such as alloy composition control, precise control of rolling starting temperature and final rolling temperature, and deformation amount of one cold rolling pass.

[0064] The invention simplifies the manufacturing process, reduces production costs, and greatly improves production efficiency. After the process innovation, about 1,200 tons have been supplied, and the performance meets user needs. The average annual supply quantity can be more than 2,000 tons, which can save about 800,000 yuan in energy and about 1 million yuan in auxiliary materials, labor, equipment depreciation, etc.

[0065] It should be understood that the order of steps or the order in which certain actions are performed is not important as long as the present invention remains operable. In addition, two or more steps or actions may be performed simultaneously.

[0066] The use of any and all examples or exemplary language, such as "for example" or "including", herein is intended only to better illustrate the invention and does not limit the scope of the invention unless otherwise claimed. No language in this specification should be construed as indicating that any non-claimed element is essential to the practice of the invention.

[0067] In addition, the numerical ranges and parameters used to define the present invention are approximate values, and the relevant values ​​in the specific embodiments have been presented as accurately as possible. However, any numerical value inherently inevitably contains standard deviations due to individual test methods. Therefore, unless otherwise expressly stated, it should be understood that all ranges, quantities, values ​​and percentages used in this disclosure are modified by "about". Here, "about" generally means that the actual value is within plus or minus 10%, 5%, 1% or 0.5% of a specific value or range.

[0068] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution, some or all of the steps can be executed in parallel or sequentially, and the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0069] Some cases are recorded in the embodiments and comparative examples of the present invention, wherein the embodiments show certain implementation modes of the present invention. However, this does not mean that the effects of the present invention can only be achieved in these cases.

[0070] In order to further illustrate the present invention, a direct rolling process of a 5052-H32 aluminum alloy sheet provided by the present invention is described in detail below in conjunction with an embodiment.

[0071] Example 1

[0072] (1) Ingot alloy composition control

[0073] Table 1 Detailed list of optimized control range of chemical composition of 5052 alloy

[0074]

[0075] (2) Ingot milling: The milling depth is 8 mm, and no metallurgical defects are allowed on the surface after milling.

[0076] (3) Ingot heating system: metal temperature 490℃, keep warm for 3h.

[0077] (4) Hot rolling: hot rough rolling is performed for 15 passes, and the thickness of the rough rolling and finishing rolling is controlled to be 30 mm.

[0078] Final hot rolling temperature: metal temperature 325℃, hot rolled rough material thickness controlled at 3.44, increase the threading speed, reduce the length of the head speed-up section, and control the head thickness difference.

[0079] (5) Deformation after one cold rolling pass: The finished product thickness is 3.12 mm and the cold deformation is about 10%.

[0080] (6) Straightening: The straightening speed is 100 m / min, the elongation is 0.3%. After cleaning, the surface of the aluminum coil is not allowed to have obvious defects such as oil stains, oil clumps, and oil strips.

[0081] (7) Finished product: Measure the thickness of the plate and cut it after the thickness meets the requirements.

[0082] Table 2 Requirements for longitudinal room temperature tensile properties

[0083]

[0084] Example 2

[0085] (1) Ingot alloy composition control

[0086] Table 3 Detailed list of optimized control range of chemical composition of 5052 alloy

[0087]

[0088] (2) Ingot milling: The milling depth is 8 mm, and no metallurgical defects are allowed on the surface after milling.

[0089] (3) Ingot heating system: metal temperature 490℃, keep warm for 3h.

[0090] (4) Hot rolling: hot rough rolling is performed for 15 passes, and the thickness of the rough rolling and finishing rolling is controlled to be 30 mm.

[0091] Final hot rolling temperature: metal temperature 325℃, hot rolled rough material thickness controlled at 3.42, increase threading speed, reduce the length of the head speed-up section, and control the head thickness difference.

[0092] (5) Deformation after one cold rolling pass: The finished product thickness is 3.10 mm and the cold deformation is about 10.3%.

[0093] (6) Straightening: The straightening speed is 100 m / min, the elongation is 0.3%. After cleaning, the surface of the aluminum coil is not allowed to have obvious defects such as oil stains, oil clumps, and oil strips.

[0094] (7) Finished product: Measure the thickness of the plate and cut it after the thickness meets the requirements.

[0095] Table 4 Requirements for longitudinal room temperature tensile properties

[0096]

[0097]

[0098] Example 3

[0099] (1) Ingot alloy composition control

[0100] Table 5 Detailed list of optimized control range of 5052 alloy chemical composition

[0101]

[0102] (2) Ingot milling: The milling depth is 8 mm, and no metallurgical defects are allowed on the surface after milling.

[0103] (3) Ingot heating system: metal temperature 490℃, keep warm for 3h.

[0104] (4) Hot rolling: hot rough rolling is performed for 15 passes, and the thickness of the rough rolling and finishing rolling is controlled to be 30 mm.

[0105] Final hot rolling temperature: metal temperature 325℃, hot rolled rough material thickness controlled at 3.44, increase the threading speed, reduce the length of the head speed-up section, and control the head thickness difference.

[0106] (5) Deformation after one cold rolling pass: The finished product thickness is 3.13 mm and the cold deformation is about 9.9%.

[0107] (6) Straightening: The straightening speed is 100 m / min, the elongation is 0.3%. After cleaning, the surface of the aluminum coil is not allowed to have obvious defects such as oil stains, oil clumps, and oil strips.

[0108] (7) Finished product: Measure the thickness of the plate and cut it after the thickness meets the requirements.

[0109] Table 6 Requirements for longitudinal room temperature tensile properties

[0110]

[0111] Example 4

[0112] When the Mg content meets the standard but the deformation in one pass is insufficient, the tensile strength of the plate is less than 215MPa. If the Mg content does not meet the standard, the performance does not meet the requirements. When the deformation in one cold rolling pass is increased to more than 15%, the tensile strength can meet the 215MPa requirement, but cracking will occur during bending, which does not meet the bending requirements.

[0113] Table 7 Tensile properties results of different variables

[0114]

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A direct rolling process for 5052-H32 aluminum alloy sheet, characterized in that: The steps include: A) preparing aluminum slabs from raw materials, milling the surface of the ingots, heating, and hot rolling to obtain hot-rolled raw materials; B) The hot rolled raw material is cold rolled once, straightened and cleaned to obtain the product.

2. The direct rolling process according to claim 1, characterized in that: The raw material formula is Si≤0.12%, Fe0.2-0.35%, Cu≤0.1%, Mn≤0.1%, Mg2.5-2.8%, Cr0.15-0.3%, Zn≤0.1%, and the balance is Al.

3. The direct rolling process according to claim 1, characterized in that: In step A), the milling depth of the ingot milling surface is ≥8 mm.

4. The direct rolling process according to claim 1, characterized in that: The heating temperature of step A) is 480-500° C., and the insulation time is ≥3h.

5. The direct rolling process according to claim 1, characterized in that: Step A) The hot rolling is performed for 13 to 19 passes; the thickness of the hot rolling is 24 mm to 32 mm; The rolling temperature is 480-500°C.

6. The direct rolling process according to claim 1, characterized in that: The final rolling temperature of the hot rolling in step A) is 310-330°C.

7. The direct rolling process according to claim 1, characterized in that: Step A) The hot rolled rough material has a thickness of 3.37 to 3.

47.

8. The direct rolling process according to claim 1, characterized in that: In step B), the deformation amount of one cold rolling pass is 8% to 11%.

9. The direct rolling process according to claim 1, characterized in that: In step B), the straightening speed is ≤100 m / min, and the elongation is 0.3% to 0.5%.

10. A 5052-H32 aluminum alloy sheet, characterized in that: The preparation method is described in any one of claims 1 to 9.

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