CN117102812A - A method for producing aluminum alloy cold-rolled sheets for new energy vehicle power battery side panels - Google Patents

Abstract

The invention discloses a production method of an aluminum alloy cold-rolled sheet for a side plate of a power battery of a new energy automobile, which comprises the following production processes: casting, sawing, milling, homogenizing, hot rolling, cold rolling, cleaning, annealing and finishing; the roller with the roughness of 0.25-0.30 um is used for cold rolling, aluminum ash generated in the rolling process can be reduced, the rolling speed of the finished pass is 150-200 mpm, the oil quantity on the surface of the outlet belt material of the rolling mill (the rolling oil is taken to the outlet of the rolling mill when the roller rotates at a high speed) can be reduced, and the effect of air purging of the outlet can be effectively improved (the time of purging through air per unit length is prolonged), so that the method provided by the invention has the following steps: the production process is short, the production cost is low, and the method is suitable for the production of products with various thicknesses, and has the effect of high surface cleanliness and high dyne value of the aluminum plate.

Description

A method for producing aluminum alloy cold-rolled sheets for new energy vehicle power battery side panels

Technical field

The invention relates to the technical field of aluminum alloy plate processing, and specifically relates to a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side plates.

Background technique

The conventional production process of 5083 aluminum alloy cold-rolled plates is: casting → homogenization → sawing → milling → heating → hot rolling → cold rolling (4 passes) → cleaning → annealing → finishing. The 5083 produced by this process The surface of aluminum alloy cold-rolled plates is heavy with aluminum ash, and only plates ≥1.2mm can be produced. For plates below 1.2mm, a cleaning process, an intermediate annealing process and a cold-rolling process need to be added. The production process is long and the production cost is high. .

The side panels of new energy vehicle power batteries need to be processed with hot-pressed insulating films. The requirements for product surface cleanliness and dyne value are extremely high (dyne value ≥ 38dyne). Its mechanical property requirements are tensile strength 275~350Mpa and yield strength. ≥125Mpa, elongation ≥12%, no cracking when bent at 90 degrees (bending radius 1.0t), finished product thickness range is 0.9-1.5mm.

Chinese patent (202110477492.3) discloses a method for preparing 5083-O battery case side plates for new energy vehicles. The process flow is: casting → homogenization → sawing → milling → heating → hot rolling → cold rolling → intermediate Annealing → cold rolling → cleaning → annealing → finishing, and the finished product is annealed using nitrogen as a protective atmosphere. The production process is long and the production cost is extremely high.

Chinese patent (202211023842. , this method requires two-stage homogenization treatment in which the ingot is cast at 435±5℃ and kept at 4 hours and at 515±5℃ for 10 hours. The thickness of the hot-rolled billet is 4.0~8.0mm. The conventional cold rolling process requires 4 passes to reach the finished product thickness. The production time is long and the production cost is high. In addition, the more cold rolling passes, the closer the aluminum ash produced during the rolling process will be combined with the aluminum plate, which will affect the surface cleanliness after cleaning. The peel strength of the PE protective film is 0.35~0.47N/10mm, which is too high. After the PE protective film is removed, there will be a large amount of residual glue on the surface of the aluminum plate, which will lead to the failure of the hot-pressed insulation film.

Contents of the invention

In view of the shortcomings of the existing technology, the purpose of the present invention is to provide a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side plates, by performing first-stage annealing in an air cushion type continuous heat treatment furnace, and then re-coiling and entering The box annealing furnace implements second-stage annealing, and finally obtains a fully annealed aluminum alloy sheet with good surface quality and uniform and fine grains.

In order to achieve the above object, the technical solution adopted by the present invention is as follows: a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which method includes the following steps: casting → sawing → milling → heating → hot rolling →cold rolling→cleaning→annealing→leveling and coating;

In the melting and casting step, the mass percentages of the chemical components of the aluminum alloy are: Si≤0.10%, Fe≤0.35%, Cu≤0.05%, Mn 0.40~0.50%, Mg 4.20~4.50%, Cr 0.05~0.10%, Zn≤ 0.15%, Ti ≤ 0.15%, other impurity elements individually ≤ 0.05%, other impurity elements in total ≤ 0.15%, the rest is Al;

In the heating step, the ingot heating temperature is 500-520°C, and the holding time is 2-4 hours;

In the hot rolling step, a hot rolling mill is used for rolling, the final hot rolling temperature is 330-345°C, and the thickness of the hot-rolled coil is 2.5-4.0mm;

In the cold rolling step, the hot-rolled coil is rolled to the finished product thickness using a roller with a roughness of 0.25-0.30 μm and a mechanical crown of 0.15-0.20 mm. The pass processing rate is 35-40%. The finished product is rolled in a pass. The control speed is 150~200mpm;

In the cleaning step, the aluminum coil is washed with alkali and water in a cleaning machine. The free alkalinity in the alkali solution is 0.7-1.5pt, and the temperature of the alkali solution is 50-60°C;

In the annealing step, the annealing temperature of the aluminum coil is 320-350°C, and the heat preservation time is 2-4 hours;

In the step of leveling and coating, a cross-cutting machine is used to flatten and coat the aluminum coil and cut it into plates. The plastic deformation rate of the aluminum coil is 0.1 to 0.5%, and the peel strength of the covered PE film is 30 to 40g/25mm.

Further, in the melting and casting step, the mass percentage of the chemical composition of the aluminum alloy is: Si≤0.10%, Fe≤0.35%, Cu≤0.05%, Mn 0.45～0.50%, Mg 4.30～4.50%, Cr 0.07～0.10% , Zn ≤ 0.15%, Ti ≤ 0.15%, other impurity elements individually ≤ 0.05%, other impurity elements in total ≤ 0.15%, and the rest is Al.

Further, in the heating step, the ingot heating temperature is 510-520°C, and the heat preservation time is 3-4 hours.

Further, in the hot rolling step, a hot rolling mill is used for rolling, the final hot rolling temperature is 335-345°C, and the thickness of the hot-rolled coil is 2.8-4.0 mm.

Further, in the cold rolling step, the hot-rolled coil blank is rolled to the finished product thickness using a roll with a roughness of 0.27-0.30 μm and a mechanical crown of 0.18-0.20 mm. The pass processing rate is 36-40%, and the finished product is The rolling speed of each pass is 160~200mpm.

Further, in the cleaning step, the aluminum coil is subjected to alkali washing and water washing in a cleaning machine. The free alkalinity in the alkali solution is 0.8-1.5pt, and the alkali solution temperature is 55-60°C.

Further, in the cleaning step, 2 to 5 g/L of alkali cleaning enhancer is added to the alkali cleaning alkali solution. The alkali cleaning enhancer consists of the following components by weight: sodium hexametaphosphate. 20 to 25 parts of sodium tripolyphosphate, 8 to 12 parts of fucose.

Further, in the cleaning step, 2 to 5 g/L of alkali cleaning enhancer is added to the alkali cleaning alkali solution. The alkali cleaning enhancer consists of the following components by weight: sodium hexametaphosphate. 22 to 25 parts of sodium tripolyphosphate, 23 to 25 parts of sodium tripolyphosphate, and 10 to 12 parts of fucose.

Further, in the annealing step, the annealing temperature of the aluminum coil is 330-350°C, and the holding time is 3-4 hours.

Furthermore, in the step of flattening and coating, a cross-cutting machine is used to flatten and coat the aluminum roll and then cut it into plates. The plastic deformation rate of the aluminum roll is 0.2-0.5%, and the peeling strength of the PE film is 35-40g. /25mm.

The present invention is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels. The subsequent processing steps of the new energy vehicle power battery side panels are stamping blanking and bending, and the requirements for the stamping resistance of the material are not high (new energy The automobile power battery casing must be deep-drawn, which requires high stamping resistance of the material). The ingot only needs to be heated to above 500°C and kept for 2 to 4 hours to ensure the smooth production of hot continuous rolling. The existing technology mainly By designing the thickness of the hot-rolled billet to be 2.5-4.0mm, and simultaneously rolling it to the finished product thickness using a roll with a mechanical crown of 0.15mm for cold rolling, the pass processing rate is 35-40% to achieve 2 passes of rolling to the finished product thickness. The surface texture of the aluminum plate after 2 passes is rough and cannot meet the product surface quality requirements. However, after 3 to 4 passes are rolled to the finished product thickness, there are many rolling passes, and the aluminum ash produced during the rolling process is closely combined with the aluminum plate. , affecting the surface cleanliness after cleaning; the present invention uses rollers with a roughness of 0.25-0.30um for cold rolling, which can reduce the aluminum ash produced during the rolling process. The rolling speed of the finished product pass is 150-200mpm, which can reduce the exit belt of the rolling mill. The amount of oil on the surface of the material (reduces the rolling oil brought to the exit of the rolling mill when the roll rotates at high speed) can also effectively improve the effect of the outlet air purge (extend the time for air purging per unit length), so that the method of the present invention has: The production process is short, the production cost is low, it is suitable for the production of products of various thicknesses, and the surface cleanliness and dyne value of the aluminum plate are high.

The present invention is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels. In the cleaning step, a special alkali cleaning enhancer is added to the alkali cleaning alkali solution. The cleaning effect is better and the alkali solution can be greatly reduced. The dosage also plays a role in increasing the dyne value of the board.

Instructions with pictures

Figure 1 is a standard diagram for aluminum gray level detection and determination according to the present invention.

Figure 2 is a picture of the plate after tearing off the film prepared in Comparative Example 1 of the present invention; there is residual glue on the surface of the plate, and the residual glue on the surface causes the dyne value to be unqualified.

Detailed ways

The following examples can help those skilled in the art understand the present invention more comprehensively, but cannot limit the present invention in any way.

The present invention is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels. The aluminum gray level detection method is: clamp a paper towel folded into a size of about 50*50mm between your fingers, and place the paper towel on the aluminum roll. One side of the surface, move to the other side, and then return to the starting side along the original path after reaching the other side. The strength of the detection is based on the paper towel pressing the surface of the strip. Observe the distribution of aluminum dust on the paper towel, and compare the severity of the aluminum dust with the standard picture; the aluminum dust grade detection and determination standards are shown in Figure 1.

Example 1:

This embodiment is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which includes the following production process: casting → sawing → milling → heating → hot rolling → cold rolling → cleaning → annealing → leveling and coating membrane.

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Heating: The heating temperature of the ingot is 520°C, and the holding time is 2 hours.

(3) Hot rolling: hot rolling mill, the final hot rolling temperature is 344°C, and the thickness of the hot rolled coil is 2.5mm.

(4) Cold rolling: Roll the hot-rolled coil with a roll with a roughness of 0.25um and a mechanical crown of 0.15mm to a finished product thickness of 0.9mm. The rolling passes are 2.5-1.5-0.9mm. The processing rate of each pass is 40%, and the rolling speed of the finished product pass is 200mpm.

(5) Cleaning: The aluminum coil is washed with alkali and water in a cleaning machine. The free alkalinity in the alkali solution is 0.7pt, and the temperature of the alkali solution is 50°C.

(6) Annealing: The annealing temperature of the aluminum coil is 320°C, and the holding time is 2 hours;

(7) Leveling and coating: Use a cross-cutting machine to flatten and coat the aluminum coil and cut it into plates. The plastic deformation rate of the aluminum coil is 0.49%, and the peeling strength of the covered PE film is 30g/25mm.

It can be seen from the above table that the surface cleanliness of the aluminum alloy cold-rolled plate for new energy vehicle power battery side panels produced according to this embodiment reaches level 1, and the dyne value after tearing off the film reaches 42dyne. The rolling plate requirements, and the ingot soaking time is 2 hours, and the cold rolling passes are 2 passes, the production time is short, and the production cost is low.

Example 2:

This embodiment is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which includes the following production process: casting → sawing → milling → heating → hot rolling → cold rolling → cleaning → annealing → leveling and coating membrane.

Si≤0.10%, Fe≤0.35%, Cu≤0.05%, Mn 0.40～0.50%, Mg 4.20～4.50%, Cr0.05～0.10%, Zn≤0.15%, Ti≤0.15%

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Heating: The heating temperature of the ingot is 500°C, and the holding time is 4 hours.

(3) Hot rolling: hot rolling mill, the final hot rolling temperature is 332°C, and the thickness of the hot rolled coil is 4.0mm.

(4) Cold rolling: Roll the hot-rolled coil with a roll with a roughness of 0.30um and a mechanical crown of 0.20mm to a finished product thickness of 1.5mm. The rolling passes are 3.5-2.2-1.5mm. The processing rate of each pass is 37.5~40%, and the rolling speed of the finished product is 150mpm.

(5) Cleaning: The aluminum coil is washed with alkali and water in a cleaning machine. The free alkalinity in the alkali solution is 1.5pt, and the alkali solution temperature is 60°C.

(6) Annealing: The annealing temperature of the aluminum coil is 350°C, and the holding time is 4 hours;

(7) Leveling and coating: Use a cross-cutting machine to flatten and coat the aluminum coil and then cut it into plates. The plastic deformation rate of the aluminum coil is 0.12%, and the peeling strength of the PE film is 40g/25mm.

It can be seen from the above table that the surface cleanliness of the aluminum alloy cold-rolled plate for new energy vehicle power battery side panels produced according to this embodiment reaches level 1, and the dyne value after tearing off the film reaches 40dyne. The rolling plate requirements, and the ingot soaking time is 4 hours, and the cold rolling passes are 2 passes, the production time is short, and the production cost is low.

Example 3:

This embodiment is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which includes the following production process: casting → sawing → milling → heating → hot rolling → cold rolling → cleaning → annealing → leveling and coating membrane.

Si≤0.10%, Fe≤0.35%, Cu≤0.05%, Mn 0.40～0.50%, Mg 4.20～4.50%, Cr0.05～0.10%, Zn≤0.15%, Ti≤0.15%

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Heating: The heating temperature of the ingot is 510°C, and the holding time is 3 hours.

(3) Hot rolling: hot rolling mill, the final hot rolling temperature is 338°C, and the thickness of the hot rolled coil is 3.0mm.

(4) Cold rolling: Roll the hot-rolled coil with a roll with a roughness of 0.28um and a mechanical crown of 0.18mm to a finished product thickness of 1.2mm. The rolling passes are 3.0-1.9-1.2mm. The processing rate of each pass is 36.7~36.8%, and the rolling speed of the finished product is 180mpm.

(5) Cleaning: The aluminum coil is washed with alkali and water in a cleaning machine. The free alkalinity in the alkali solution is 1.0pt, and the alkali solution temperature is 55°C.

(6) Annealing: The annealing temperature of the aluminum coil is 330°C, and the holding time is 3 hours;

(7) Leveling and coating: Use a cross-cutting machine to flatten and coat the aluminum coil and then cut it into plates. The plastic deformation rate of the aluminum coil is 0.24%, and the peeling strength of the covered PE film is 35g/25mm.

It can be seen from the above table that the surface cleanliness of the aluminum alloy cold-rolled plate for new energy vehicle power battery side panels produced according to this embodiment reaches level 1, and the dyne value after tearing off the film reaches 41dyne. The rolling plate requirements, and the ingot soaking time is 3 hours, and the cold rolling passes are 2 passes, the production time is short, and the production cost is low.

Example 4:

This embodiment is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which includes the following production process: casting → sawing → milling → heating → hot rolling → cold rolling → cleaning → annealing → leveling and coating membrane.

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Heating: The heating temperature of the ingot is 520°C, and the holding time is 2 hours.

(3) Hot rolling: hot rolling mill, the final hot rolling temperature is 344°C, and the thickness of the hot rolled coil is 2.5mm.

(4) Cold rolling: Roll the hot-rolled coil with a roll with a roughness of 0.25um and a mechanical crown of 0.15mm to a finished product thickness of 0.9mm. The rolling passes are 2.5-1.5-0.9mm. The processing rate of each pass is 40%, and the rolling speed of the finished product pass is 200mpm.

(5) Cleaning: The aluminum coil is subjected to alkali cleaning and water washing in a cleaning machine. The free alkalinity in the alkali solution is 0.7pt, and the alkali solution temperature is 50°C; 2g/L alkali solution is added to the alkali cleaning solution to strengthen cleaning. The alkali cleaning enhancer is composed of the following components by weight: 20 parts of sodium hexametaphosphate, 20 parts of sodium tripolyphosphate, and 8 parts of fucose.

(6) Annealing: The annealing temperature of the aluminum coil is 320°C, and the holding time is 2 hours;

(7) Leveling and coating: Use a cross-cutting machine to flatten and coat the aluminum coil and cut it into plates. The plastic deformation rate of the aluminum coil is 0.49%, and the peeling strength of the covered PE film is 30g/25mm.

It can be seen from the above table that the surface cleanliness of the aluminum alloy cold-rolled plate for new energy vehicle power battery side panels produced according to this embodiment reaches level 1, and the dyne value after tearing off the film reaches 42dyne. The rolling plate requirements, and the ingot soaking time is 2 hours, and the cold rolling passes are 2 passes, the production time is short, and the production cost is low.

Example 5:

This embodiment is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which includes the following production process: casting → sawing → milling → heating → hot rolling → cold rolling → cleaning → annealing → leveling and coating membrane.

Si≤0.10%, Fe≤0.35%, Cu≤0.05%, Mn 0.40～0.50%, Mg 4.20～4.50%, Cr0.05～0.10%, Zn≤0.15%, Ti≤0.15%

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Heating: The heating temperature of the ingot is 500°C, and the holding time is 4 hours.

(3) Hot rolling: hot rolling mill, the final hot rolling temperature is 332°C, and the thickness of the hot rolled coil is 4.0mm.

(4) Cold rolling: Roll the hot-rolled coil with a roll with a roughness of 0.30um and a mechanical crown of 0.20mm to a finished product thickness of 1.5mm. The rolling passes are 3.5-2.2-1.5mm. The processing rate of each pass is 37.5~40%, and the rolling speed of the finished product is 150mpm.

(5) Cleaning: The aluminum coil is subjected to alkali cleaning and water washing in a cleaning machine. The free alkalinity in the alkali solution is 1.5pt, and the alkali solution temperature is 60°C; 5g/L alkali solution is added to the alkali cleaning solution to strengthen cleaning. The alkali cleaning enhancer is composed of the following components by weight: 25 parts of sodium hexametaphosphate, 25 parts of sodium tripolyphosphate, and 12 parts of fucose.

(6) Annealing: The annealing temperature of the aluminum coil is 350°C, and the holding time is 4 hours;

(7) Leveling and coating: Use a cross-cutting machine to flatten and coat the aluminum coil and then cut it into plates. The plastic deformation rate of the aluminum coil is 0.12%, and the peeling strength of the PE film is 40g/25mm.

It can be seen from the above table that the surface cleanliness of the aluminum alloy cold-rolled plate for new energy vehicle power battery side panels produced according to this embodiment reaches level 1, and the dyne value after tearing off the film reaches 40dyne. The rolling plate requirements, and the ingot soaking time is 4 hours, and the cold rolling passes are 2 passes, the production time is short, and the production cost is low.

Example 6:

This embodiment is a production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels, which includes the following production process: casting → sawing → milling → heating → hot rolling → cold rolling → cleaning → annealing → leveling and coating membrane.

Si≤0.10%, Fe≤0.35%, Cu≤0.05%, Mn 0.40～0.50%, Mg 4.20～4.50%, Cr0.05～0.10%, Zn≤0.15%, Ti≤0.15%

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Heating: The heating temperature of the ingot is 510°C, and the holding time is 3 hours.

(3) Hot rolling: hot rolling mill, the final hot rolling temperature is 338°C, and the thickness of the hot rolled coil is 3.0mm.

(4) Cold rolling: Roll the hot-rolled coil with a roll with a roughness of 0.28um and a mechanical crown of 0.18mm to a finished product thickness of 1.2mm. The rolling passes are 3.0-1.9-1.2mm. The processing rate of each pass is 36.7~36.8%, and the rolling speed of the finished product is 180mpm.

(5) Cleaning: The aluminum coil is subjected to alkali cleaning and water washing in a cleaning machine. The free alkalinity in the alkali solution is 1.0pt, and the alkali solution temperature is 55°C; 4g/L alkali solution is added to the alkali cleaning solution to strengthen cleaning. The alkali cleaning enhancer is composed of the following components by weight: 22 parts of sodium hexametaphosphate, 23 parts of sodium tripolyphosphate, and 10 parts of fucose.

(6) Annealing: The annealing temperature of the aluminum coil is 330°C, and the holding time is 3 hours;

(7) Leveling and coating: Use a cross-cutting machine to flatten and coat the aluminum coil and then cut it into plates. The plastic deformation rate of the aluminum coil is 0.24%, and the peeling strength of the covered PE film is 35g/25mm.

It can be seen from the above table that the surface cleanliness of the aluminum alloy cold-rolled plate for new energy vehicle power battery side panels produced according to this embodiment reaches level 1, and the dyne value after tearing off the film reaches 41dyne. The rolling plate requirements, and the ingot soaking time is 3 hours, and the cold rolling passes are 2 passes, the production time is short, and the production cost is low.

Comparative example 1

This embodiment is a production method of 5083 aluminum alloy cold-rolled plates, which includes the following production process: casting → sawing → milling → homogenization → hot rolling → cold rolling → cleaning → annealing → finishing.

(1) Casting: The mass percentage of chemical elements in the ingot after melting and casting is

(2) Homogenization: The ingot is heated to 520°C and then kept warm for 10 hours.

(3) Hot rolling: The final rolling temperature of hot rolling is 335°C, and the thickness of the hot-rolled billet is 4.0mm.

(4) Cold rolling: Roll the hot-rolled billet to 1.0mm, and the rolling passes are 4.0-2.8-1.96-1.37-1.0mm.

(5) Finishing: Use a cross-cutting machine to flatten the aluminum coil and coat it with film and then cut it into plates. The peel strength of the PE film covered is 50g/25mm.

From the data in the above table, it can be seen that the heat preservation time of 5083 aluminum alloy cold-rolled plate ingots produced by conventional processes is 10 hours, the number of cold rolling passes is 4, the surface cleanliness of the finished product is level 2, and the dyne value after tearing off the film is 36dyne, and there is residual glue on the surface of the aluminum plate after peeling off the film. The production process of this process is long, the production cost is high, and the surface quality cannot meet the requirements of aluminum alloy cold-rolled sheets for new energy vehicle power battery side panels.

It can be seen from the above test results that the production method of aluminum alloy cold-rolled plates for new energy vehicle power battery side panels of the present invention includes the following production process: casting → sawing → milling → homogenization → hot rolling → cold rolling → cleaning → Annealing → finishing; cold rolling with rolls with a roughness of 0.25~0.30um can reduce the aluminum ash produced during the rolling process. The rolling speed of the finished product pass is 150~200mpm, which can reduce the amount of oil on the surface of the strip at the outlet of the rolling mill. (Reduce the rolling oil being brought to the exit of the rolling mill when the roll rotates at high speed) It can also effectively improve the effect of the outlet air purge (prolong the time of air purging per unit length), so that the method of the present invention has the following advantages: short production process and low production cost Low, suitable for the production of products of various thicknesses, the surface cleanliness and dyne value of the aluminum plate are high; in the cleaning step, a special alkali cleaning enhancer is added to the alkali cleaning alkali solution, which has a better cleaning effect and can significantly Reducing the amount of alkali solution also plays a role in increasing the dyne value of the board.

Although the present invention has been described in detail with general descriptions and specific embodiments above, it is obvious to those skilled in the art that some modifications or improvements can be made based on the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection claimed by the present invention.

Claims (10)

1. The production method of the aluminum alloy cold-rolled sheet for the side plate of the power battery of the new energy automobile is characterized by comprising the following steps: casting, sawing, milling faces, heating, hot rolling, cold rolling, cleaning, annealing and leveling the coating film;

in the casting step, the aluminum alloy comprises the following chemical components in percentage by mass: less than or equal to 0.10 percent of Si, less than or equal to 0.35 percent of Fe, less than or equal to 0.05 percent of Cu, 0.40 to 0.50 percent of Mn, 4.20 to 4.50 percent of Mg, 0.05 to 0.10 percent of Cr, less than or equal to 0.15 percent of Zn, less than or equal to 0.15 percent of Ti, less than or equal to 0.05 percent of other impurity elements, less than or equal to 0.15 percent of other impurity elements in total, and the balance of Al;

in the heating step, the heating temperature of the cast ingot is 500-520 ℃ and the heat preservation time is 2-4 hours;

in the hot rolling step, a hot continuous rolling mill is adopted for rolling, the hot rolling finishing temperature is 330-345 ℃, and the thickness of a hot rolled coil blank is 2.5-4.0 mm;

in the cold rolling step, the hot rolled coil blank is rolled to the thickness of a finished product by a roller with the roughness of 0.25-0.30 mu m and the mechanical convexity of 0.15-0.20 mm, the pass processing rate is 35-40%, and the pass rolling speed of the finished product is 150-200 mpm;

in the cleaning step, the aluminum coil is subjected to alkaline cleaning and water washing in a cleaning machine, the free alkalinity in alkaline solution is 0.7-1.5 pt, and the temperature of the alkaline solution is 50-60 ℃;

in the annealing step, the annealing temperature of the aluminum coil is 320-350 ℃, and the heat preservation time is 2-4 hours;

in the leveling and laminating step, a transverse cutting machine is used for leveling and laminating an aluminum roll, then the aluminum roll is sheared into a plate, the plastic deformation rate of the aluminum roll is 0.1-0.5%, and the peel strength of the PE film is 30-40 g/25mm.

2. The method for producing an aluminum alloy cold-rolled sheet for a power battery side plate of a new energy automobile according to claim 1, wherein in the casting step, the aluminum alloy comprises the following chemical components in percentage by mass: less than or equal to 0.10 percent of Si, less than or equal to 0.35 percent of Fe, less than or equal to 0.05 percent of Cu, 0.45 to 0.50 percent of Mn, 4.30 to 4.50 percent of Mg, 0.07 to 0.10 percent of Cr, less than or equal to 0.15 percent of Zn, less than or equal to 0.15 percent of Ti, less than or equal to 0.05 percent of other impurity elements, less than or equal to 0.15 percent of other impurity elements in total, and the balance of Al.

3. The method for producing aluminum alloy cold-rolled sheet for power battery side plate of new energy automobile according to claim 1, wherein in the heating step, the heating temperature of the cast ingot is 510-520 ℃ and the heat preservation time is 3-4 hours.

4. The method for producing an aluminum alloy cold-rolled sheet for a power battery side plate of a new energy automobile according to claim 1, wherein in the hot rolling step, a hot continuous rolling mill is used for rolling, the hot rolling finishing temperature is 335-345 ℃, and the thickness of a hot rolled coil is 2.8-4.0 mm.

5. The method for producing an aluminum alloy cold-rolled sheet for a side plate of a power battery of a new energy automobile according to claim 1, wherein in the cold rolling step, a hot-rolled coil blank is rolled to a finished product thickness by a roll with a roughness of 0.27-0.30 μm and a mechanical convexity of 0.18-0.20 mm, a pass reduction ratio of 36-40% and a finished product pass rolling speed of 160-200 mpm.

6. The method for producing aluminum alloy cold-rolled sheet for power battery side plate of new energy automobile according to claim 1, wherein in the cleaning step, the aluminum coil is subjected to alkali cleaning and water cleaning in a cleaning machine, the free alkalinity in alkali solution is 0.8-1.5 pt, and the temperature of alkali solution is 55-60 ℃.

7. The method for producing the aluminum alloy cold-rolled sheet for the power battery side plate of the new energy automobile according to claim 1, wherein in the cleaning step, 2-5 g/L of alkali liquor cleaning reinforcing agent is added into alkali liquor for alkali cleaning, and the alkali liquor cleaning reinforcing agent consists of the following components in parts by weight: 20-25 parts of sodium hexametaphosphate, 20-25 parts of sodium tripolyphosphate and 8-12 parts of fucose.

8. The method for producing the aluminum alloy cold-rolled sheet for the power battery side plate of the new energy automobile according to claim 7, wherein in the cleaning step, 2-5 g/L of alkali liquor cleaning reinforcing agent is added in alkali liquor for alkali cleaning, and the alkali liquor cleaning reinforcing agent consists of the following components in parts by weight: 22-25 parts of sodium hexametaphosphate, 23-25 parts of sodium tripolyphosphate and 10-12 parts of fucose.

9. The method for producing an aluminum alloy cold-rolled sheet for a power battery side plate of a new energy automobile according to claim 1, wherein in the annealing step, the annealing temperature of the aluminum coil is 330-350 ℃ and the heat preservation time is 3-4 hours.

10. The method for producing the aluminum alloy cold-rolled sheet for the power battery side plate of the new energy automobile according to claim 1, wherein in the step of leveling and laminating, an aluminum coil is cut into a sheet material after being leveled and laminated by a transverse cutting machine, the plastic deformation rate of the aluminum coil is 0.2-0.5%, and the peel strength of a PE film is 35-40 g/25mm.