Annealing method of 2000 series aluminum alloy plate

Abstract

The invention relates to an annealing method of a 2000 series aluminum alloy plate, in particular to an annealing method of a 2000 series aluminum alloy plate. In order to solve the problems of long equipment occupation time and low production efficiency caused by the use of a furnace cooling mode in the traditional annealing process, the method comprises the following steps: sawing hot-rolled 2000 series aluminum alloy plates, annealing, discharging the 2000 series aluminum alloy plates subjected to heat preservation from a furnace, hoisting the 2000 series aluminum alloy plates to an open space, stacking and placing the plates, and carrying out heat preservation on the 2000 series aluminum alloy plates. And completely covering the plate with asbestos cloth, and cooling. According to the annealing method for the 2000 series aluminum alloy plate, annealing slow cooling can be achieved, furnace cooling cooling can be replaced with the method, the cooling rate can be controlled through the asbestos cloth blanket thickness, equipment occupation can be reduced by 600 h / year, and the productivity of an aging furnace is widened by about 2000 t / year. The method is applied to the technical field of aluminum alloy machining.

Description

Technical Field

[0001] This invention relates to an annealing method for 2000 series aluminum alloy sheets. Background Technology

[0002] Aluminum alloys have low density but relatively high strength, and possess excellent electrical and thermal conductivity and corrosion resistance, making them one of the most widely used non-ferrous metal structural materials in industry. They are extensively used in aerospace, automotive, machinery manufacturing, shipbuilding, and chemical industries. Aluminum alloy plates, compared to other types of aluminum alloys, account for a relatively high proportion of aluminum alloy usage and are the primary form of aluminum alloy supply.

[0003] For thick aluminum alloy plates, especially those of heat-treatable alloys, annealed plates generally need to be cooled in the furnace after annealing to ensure low strength, eliminate work hardening, and facilitate subsequent processing, prevent deformation, and ensure stable performance. However, furnace cooling in industrial production takes up a lot of time in the annealing furnace, resulting in low production efficiency and affecting output. Summary of the Invention

[0004] The purpose of this invention is to solve the problems of long equipment occupation time and low production efficiency caused by the traditional furnace cooling method in annealing process, and to provide an annealing method for 2000 series aluminum alloy plates, so as to achieve the characteristics of low softening strength and stable performance after annealing of 2000 series aluminum alloy plates.

[0005] This invention discloses an annealing method for 2000 series aluminum alloy sheets, which is carried out according to the following steps:

[0006] 1. Sawing of hot-rolled sheet metal;

[0007] The hot-rolled 2000 series aluminum alloy sheet is sawn to obtain the sawn hot-rolled aluminum alloy sheet.

[0008] II. Insulation:

[0009] The sawn aluminum alloy hot-rolled sheet is placed in a box furnace and heated to 400℃~450℃, and held at 400℃~450℃ for 3h~8h to obtain the heat-held 2000 series aluminum alloy sheet.

[0010] III. Cooling:

[0011] After the 2000 series aluminum alloy sheets are heated and removed from the furnace, they are hoisted to an open space, stacked, covered with asbestos cloth, and cooled to obtain annealed 2000 series aluminum alloy sheets with stable performance.

[0012] The beneficial effects of this invention are:

[0013] (1) The annealing method of the 2000 series aluminum alloy sheet of the present invention can realize the preparation of annealed 2000 series aluminum alloy sheet. Compared with the process of not adding asbestos insulation, the aluminum alloy sheet prepared by this method has stable performance and strength below the requirements, and the production time is shorter.

[0014] (2) The annealing method of the 2000 series aluminum alloy sheet of the present invention can achieve slow cooling during annealing, and can replace furnace cooling. The cooling rate can be controlled by the thickness of the asbestos cloth covering, which can reduce equipment occupation by 600h / year and expand the aging furnace capacity by about 2000t / year.

[0015] (3) This invention explores that intermediate annealing technology can be applied to 5000 and 7000 series aluminum alloy plates, which can meet the practical needs of modern aluminum alloy manufacturers for high efficiency and low cost. Attached Figure Description

[0016] Figure 1 The image shows the actual 2000 series aluminum alloy sheet prepared in Example 1.

[0017] Figure 2 The image shows the microstructure of the 2000 series aluminum alloy sheet prepared in Example 1. Detailed Implementation

[0018] The technical solution of the present invention is not limited to the specific embodiments listed below, but also includes any combination of the specific embodiments.

[0019] Specific Implementation Method 1: This implementation method describes an annealing method for 2000 series aluminum alloy sheets, which is carried out according to the following steps:

[0020] 1. Sawing of hot-rolled sheet metal;

[0021] The hot-rolled 2000 series aluminum alloy sheet is sawn to obtain the sawn hot-rolled aluminum alloy sheet.

[0022] II. Insulation:

[0023] The sawn aluminum alloy hot-rolled sheet is placed in a box furnace and heated to 400℃~450℃, and held at 400℃~450℃ for 3h~8h to obtain the heat-held 2000 series aluminum alloy sheet.

[0024] III. Cooling:

[0025] After the 2000 series aluminum alloy sheets are heated and removed from the furnace, they are hoisted to an open space, stacked, covered with asbestos cloth, and cooled to obtain annealed 2000 series aluminum alloy sheets with stable performance.

[0026] The annealing method described in this specific embodiment is applicable to the annealing of 5000 series and 7000 series aluminum alloy sheets; it can be used for 8mm~20mm thick sheets as well as 20mm~120mm thin sheets.

[0027] Specific Implementation Method Two: This implementation method is the same as Specific Implementation Method One in that the 2000 series aluminum alloy sheet is composed of 4-6% Cu, 0.1-1% Mg, 0.1-0.5% Ti, and the balance Al by mass fraction. Everything else is the same as in Specific Implementation Method One.

[0028] Specific Implementation Method 3: This implementation method differs from Specific Implementation Method 1 or 2 in that: in step 2, the temperature is raised to 420℃.

[0029] Everything else is the same as in Specific Implementation Method 1 or 2.

[0030] Specific Implementation Method Four: This implementation method differs from Specific Implementation Methods One to Three in that: after heating in step two, the temperature is maintained for 6 hours. Everything else is the same as in Specific Implementation Methods One to Three.

[0031] Specific Implementation Method Five: This implementation method differs from Specific Implementation Methods One to Four in that 3 to 5 layers of asbestos cloth are covered in step three. Everything else is the same as in Specific Implementation Methods One to Four.

[0032] Specific Implementation Method Six: This implementation method differs from Specific Implementation Methods One to Five in that the thickness of the asbestos cloth is 2-4 cm. Everything else is the same as in Specific Implementation Methods One to Five.

[0033] Specific Implementation Method Seven: This implementation method differs from Specific Implementation Methods One to Six in that the cooling rate in step three is 20-30℃ / h. Everything else is the same as in Specific Implementation Methods One to Six.

[0034] The beneficial effects of the present invention are verified using the following embodiments:

[0035] Example 1: An annealing method for 2000 series aluminum alloy sheet, characterized in that the preparation method is carried out according to the following steps:

[0036] I. Sawing of hot-rolled sheet metal:

[0037] The hot-rolled 2000 series aluminum alloy sheet is sawn to obtain the sawn hot-rolled aluminum alloy sheet.

[0038] II. Insulation:

[0039] The sawn aluminum alloy hot-rolled sheet is placed in a box furnace, heated to 420℃, and held at 420℃ for 6 hours to obtain the heat-held 2000 series aluminum alloy sheet.

[0040] III. Cooling:

[0041] After the 2000 series aluminum alloy sheets are heated and removed from the furnace, they are hoisted to an open space, stacked, and completely covered with three layers of 3cm thick asbestos cloth. The cooling rate is 20-25℃ / h to obtain annealed 2000 series aluminum alloy sheets with stable performance.

[0042] The 2000 series aluminum alloy sheet prepared in this embodiment has the following microstructure: Figure 1 As shown, the annealing temperature reaches above the recrystallization temperature, and aging completely recrystallizes to obtain an equiaxed crystal structure, which can achieve uniform deformation. It achieves tensile strength below 220 MPa, yield strength below 110 MPa, elongation above 10%, strong machinability and corrosion resistance, and relatively stable overall performance.

[0043] The 2000 series aluminum alloy sheet prepared by the method in this embodiment is shown in the physical example. Figure 2 As shown, it can be applied to aluminum plate applications in the aerospace industry, reducing production costs, reducing equipment occupancy by 600 hours / year, and expanding the capacity of aging furnaces by approximately 2000 tons / year.

Claims

1. An annealing method for 2000 series aluminum alloy sheets, characterized in that... The preparation method is carried out according to the following steps:

1. Sawing of hot-rolled sheet metal; The hot-rolled 2000 series aluminum alloy sheet is sawn to obtain the sawn hot-rolled aluminum alloy sheet. II. Insulation: The sawn aluminum alloy hot-rolled sheet is placed in a box furnace and heated to 400℃~450℃, and held at 400℃~450℃ for 3h~8h to obtain the heat-held 2000 series aluminum alloy sheet. III. Cooling: After the 2000 series aluminum alloy sheets are heated and removed from the furnace, they are hoisted to an open space, stacked, covered with asbestos cloth, and cooled to obtain annealed 2000 series aluminum alloy sheets with stable performance.

2. The annealing method for 2000 series aluminum alloy sheet according to claim 1, characterized in that, 2000 series aluminum alloy sheets consist of 4-6% Cu, 0.1-1% Mg, 0.1-0.5% Ti, and the balance Al.

3. The annealing method for 2000 series aluminum alloy sheet according to claim 1, characterized in that, Step 2: Increase the temperature to 420℃.

4. The annealing method for 2000 series aluminum alloy sheet according to claim 1, characterized in that, Step two: After heating, keep warm for 6 hours.

5. The annealing method for 2000 series aluminum alloy sheet according to claim 1, characterized in that, In step three, cover with 3 to 5 layers of asbestos cloth.

6. The annealing method for 2000 series aluminum alloy sheet according to claim 1, characterized in that, The thickness of the asbestos cloth is 2-4 cm.

7. The annealing method for 2000 series aluminum alloy sheet according to claim 1, characterized in that, The cooling rate in step three is 20-30℃ / h.

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