阅读说明：本技术 新能源动力电池壳、铝合金及其制造方法 (New energy power battery case, aluminum alloy and manufacturing method thereof ) 是由 曹琦 刘二磊 习博建 马建兵 于 2020-05-08 设计创作，主要内容包括：本发明提供了一种新能源动力电池壳、铝合金及其制造方法。其中,该铝合金由以下重量百分比的组分组成：Si：0.17％～0.30％,Fe：0.50％～0.60％,Cu：0.02％～0.08％,Mn：0.90％～1.05％,Mg：0.02％～0.06％,Zn：≤0.05％,Ti：0.015％～0.04％,余量为Al及单个元素小于0.05％、总量小于0.15％的不可避免杂质。本发明提供的铝合金有良好的塑性变形能力且能满足电池壳的深冲性能要求以及表面质量要求。(The invention provides a new energy power battery case, an aluminum alloy and a manufacturing method thereof. Wherein the aluminum alloy comprises the following components in percentage by weight: si: 0.17% -0.30%, Fe: 0.50-0.60%, Cu: 0.02% -0.08%, Mn: 0.90% -1.05%, Mg: 0.02% -0.06%, Zn: less than or equal to 0.05 percent, Ti: 0.015-0.04%, the balance of Al and single elements less than 0.05%, and inevitable impurities with the total amount less than 0.15%. The aluminum alloy provided by the invention has good plastic deformation capability and can meet the requirements of deep drawing performance and surface quality of battery cases.)

1. The aluminum alloy for the new energy power battery shell is characterized by comprising the following components in percentage by weight: si: 0.17% -0.30%, Fe: 0.50-0.60%, Cu: 0.02% -0.08%, Mn: 0.90% -1.05%, Mg: 0.02% -0.06%, Zn: less than or equal to 0.05 percent, Ti: 0.015-0.04%, the balance of Al and single elements less than 0.05%, and inevitable impurities with the total amount less than 0.15%.

2. An aluminium alloy according to claim 1, wherein the aluminium alloy has an elongation > 40% and a cupping value > 12.5 mm.

3. An aluminium alloy according to claim 1, wherein the aluminium alloy has an average grain size < 30 μm.

4. A method of manufacturing an aluminium alloy according to any one of claims 1 to 3, comprising the steps of:

homogenizing the cast ingot;

carrying out hot rolling on the homogenized cast ingot to obtain a hot rolled blank; wherein the initial rolling temperature of the hot rolling is 550-570 ℃;

carrying out rough rolling on the hot rolled blank to obtain a rough rolled blank;

carrying out finish rolling on the rough rolling blank to obtain an aluminum coil;

and continuously annealing the aluminum coil to obtain a finished product.

5. The method of claim 4, wherein the annealing temperature of the continuous annealing is 430-460 ℃ and the running speed of the aluminum coil is 5-7 m/min.

6. The method according to claim 4, wherein the homogenization temperature is 595-610 ℃, the holding time is 12-14 h, and the temperature is reduced to 550-570 ℃ after the holding is finished.

7. The method according to claim 4, wherein the hot rolling has a finishing temperature of 340 ℃ to 360 ℃.

8. The method according to claim 4, wherein the smelting temperature of the ingot is 740-760 ℃, the electromagnetic stirring is carried out for 2-3 times during smelting, each time lasts 10-12 min, the refining temperature is 730-750 ℃, the refining time is 15-20 min, and the casting temperature is 695-705 ℃.

9. A new energy power battery case, characterized by comprising the aluminum alloy of any one of claims 1 to 3.

Technical Field

The invention belongs to the field of aluminum alloy, and particularly relates to aluminum alloy for a new energy power battery shell, a manufacturing method of the aluminum alloy and the new energy power battery shell comprising the aluminum alloy.

Background

The new energy power battery is known as the heart of a new energy automobile, and the battery shell of the new energy power battery is usually made of aluminum alloy. During the forming process of the battery shell, the deformation is large, and the surface of the battery shell cannot be scratched when the battery shell is in contact with a mold. However, the existing aluminum alloy for the new energy power battery shell has large crystal grains and insufficient deep drawing performance, the surface of the shell is easy to be rough after forming, the appearance quality is poor, the replacement frequency of a die in the punch forming process can be increased, and the production efficiency is reduced.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides an aluminum alloy for a new energy power battery case, a manufacturing method of the aluminum alloy and the new energy power battery case comprising the aluminum alloy.

The invention aims to provide an aluminum alloy for a new energy power battery case, which consists of the following components in percentage by weight: si: 0.17% -0.30%, Fe: 0.50-0.60%, Cu: 0.02% -0.08%, Mn: 0.90% -1.05%, Mg: 0.02% -0.06%, Zn: less than or equal to 0.05 percent, Ti: 0.015-0.04%, the balance of Al and single elements less than 0.05%, and inevitable impurities with the total amount less than 0.15%.

In some embodiments of the invention, the aluminum alloy has an elongation of > 40% and a cupping value of > 12.5 mm.

In some embodiments of the invention, the aluminum alloy has an average grain size < 30 μm.

A second object of the present invention is to provide a method for producing the above aluminum alloy, which comprises:

homogenizing the cast ingot;

carrying out hot rolling on the homogenized cast ingot to obtain a hot rolled blank; wherein the initial rolling temperature of the hot rolling is 550-570 ℃;

carrying out rough rolling on the hot rolled blank to obtain a rough rolled blank;

carrying out finish rolling on the rough rolling blank to obtain an aluminum coil;

and continuously annealing the aluminum coil to obtain a finished product.

In some embodiments of the invention, the annealing temperature of the continuous annealing is 430-460 ℃, and the running speed of the aluminum coil is 5-7 m/min.

In some embodiments of the invention, the homogenization temperature is 595-610 ℃, the holding time is 12-14 h, and the temperature is reduced to 550-570 ℃ after the holding is finished.

In some embodiments of the invention, the finishing temperature of the hot rolling is 340 ℃ to 360 ℃.

In some embodiments of the invention, the smelting temperature of the ingot is 740-760 ℃, the electromagnetic stirring is carried out for 2-3 times during smelting, each time lasts 10-12 min, the refining temperature is 730-750 ℃, the refining time is 15-20 min, and the casting temperature is 695-705 ℃.

The invention also aims to provide a new energy power battery case which comprises the aluminum alloy.

The aluminum alloy provided by the invention has good plastic deformation capability and can meet the requirements of deep drawing performance and surface quality of battery cases. The invention adopts a mode of direct hot rolling after homogenization, the initial rolling temperature is above 550 ℃, the final rolling temperature is correspondingly improved, the static recrystallization of the material after the hot rolling is finished is more sufficient, and the structure is more uniform. By adopting a continuous annealing mode, the temperature rise speed of the material is high in the recrystallization annealing process, and fine isometric crystal grains can be obtained. The new energy power battery shell has excellent performance.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a process flow diagram of manufacturing an aluminum alloy for a new energy power battery case according to an embodiment of the present invention.

Fig. 2 is a polarization diagram of a grain structure of an aluminum alloy for a new energy power battery case according to an embodiment of the present invention.

Fig. 3 is a polarization diagram of a grain structure of an aluminum alloy for a new energy power battery case according to an embodiment of the present invention.

FIG. 4 is a polarization diagram of the grain structure of the aluminum alloy for new energy power battery case according to an embodiment of the present invention.

FIG. 5 is a polarization diagram of the grain structure of the aluminum alloy for a new energy power battery case according to an embodiment of the present invention.

FIG. 6 is a diagram of a crystal grain structure polarized light of an aluminum alloy for a new energy power battery case according to a comparative example of the present invention.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms "including" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those steps or elements listed, but may alternatively include other steps or elements not listed, or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. It is explicitly and implicitly understood by one skilled in the art that the embodiments described herein can be combined with other embodiments.

The invention provides an aluminum alloy for a new energy power battery shell, which comprises the following components in percentage by weight: si: 0.17% -0.30%, Fe: 0.50-0.60%, Cu: 0.02% -0.08%, Mn: 0.90% -1.05%, Mg: 0.02% -0.06%, Zn: less than or equal to 0.05 percent, Ti: 0.015-0.04%, the balance of Al and single elements less than 0.05%, and inevitable impurities with the total amount less than 0.15%.

The elongation of the aluminum alloy for the new energy power battery shell is more than 40%, and the cupping value is more than 12.5mm, so that the aluminum alloy has good plastic deformation capability. The crystal grains are fine and uniform, the average crystal grain size is less than 30 mu m, and the material has excellent deep drawing performance.

The method for manufacturing the aluminum alloy can comprise the following steps:

(1) homogenizing the ingot.

In some embodiments of the invention, the ingot may be placed into a homogenizing furnace for homogenization. Wherein the homogenization temperature is 595-610 ℃, the heat preservation time is 12-14 h, and the temperature is reduced to 550-570 ℃ after the heat preservation is finished.

(2) And hot rolling the homogenized cast ingot to obtain a hot rolled blank.

In some embodiments of the invention, the hot rolling is performed at a start rolling temperature of 550 ℃ to 570 ℃ and a finish rolling temperature of 340 ℃ to 360 ℃. Hot rolling can be carried out on a four-roll reversing hot mill.

The invention adopts a mode of direct hot rolling after homogenization, the initial rolling temperature is above 550 ℃, the final rolling temperature is correspondingly improved, the static recrystallization of the material after the hot rolling is finished is more sufficient, and the structure is more uniform.

(3) And carrying out rough rolling on the hot rolled blank to obtain a rough rolled blank.

(4) And (5) performing finish rolling on the rough rolling blank to obtain an aluminum coil.

In some embodiments of the invention, the rough rolling and finish rolling may be performed on a cold rolling mill.

(5) And continuously annealing the aluminum coil to obtain a finished product.

In some embodiments of the invention, the annealing temperature of the continuous annealing is 430-460 ℃, and the running speed of the aluminum coil is 5-7 m/min.

If the length of the aluminum coil is 120m, the aluminum coil can be continuously annealed within about 20min, and the temperature rise speed of the aluminum coil is high in the recrystallization annealing process, so that fine isometric crystal grains can be obtained.

In some embodiments of the invention, when the ingot is prepared, the smelting temperature is 740-760 ℃, the electromagnetic stirring is carried out for 2-3 times during smelting, each time lasts 8-12 min, the refining temperature is 730-750 ℃, the refining time is 15-20 min, and the casting temperature is 695-705 ℃.

The new energy power battery shell made of the aluminum alloy has excellent deep drawing performance, and the molded surface is clean and has no scratch and burr, and no oil stain and aluminum scrap residue after cleaning.

The present invention will be described below with reference to specific examples. The values of the process conditions taken in the following examples are exemplary and ranges of values are provided as indicated in the foregoing summary, and reference may be made to conventional techniques for process parameters not specifically noted. The detection methods used in the following examples are all conventional in the industry.