WO2019214242A1

WO2019214242A1 - Aluminum alloy strip for battery and preparation method therefor

Info

Publication number: WO2019214242A1
Application number: PCT/CN2018/122456
Authority: WO
Inventors: 张全成; 吴永新
Original assignee: 江苏常铝铝业股份有限公司
Priority date: 2018-05-11
Filing date: 2018-12-20
Publication date: 2019-11-14
Also published as: CN108754249A; CN108754249B

Abstract

An aluminum alloy strip for a battery and a preparation method therefor. The aluminum alloy strip comprises, by weight percentage, the following alloy components: Si: 0.71-0.75%, Fe: 0.65-0.68%, Cu: 0.11-0.14%, Mn: 0.06-0.068%, Mg: 0.04-0.048%, Cr: 0.06-0.065%, Zn: ≤0.03%, and Ti: 0.035-0.04%, with the balance being Al. The preparation method comprises the following steps: ally smelting; blank forming based on hot rolling; aging treatment; cold rolling and annealing treatment; and aging treatment. By means of reasonable alloy component proportion design and molding process design, i.e., hot rolling, cold rolling, annealing treatment, and two aging treatments, the tensile strength, ductility and stamping properties of the prepared aluminum alloy strip are significantly improved, and thus the molding rate of the aluminum alloy strip for preparing a battery housing by stamping is increased. The aluminum alloy strip is an ideal strip for preparing an aluminum alloy battery, and has broad application prospects in the field of aluminum alloy batteries.

Description

Aluminum alloy strip for battery and preparation method thereof

Cross-reference to related applications

The present application claims priority to Chinese Patent Application No. 201810446644.1, entitled "Aluminum Alloy Strip for Battery and Its Preparation Method", filed on May 11, 2018, the entire contents of which are incorporated by reference. In this application.

Technical field

The present application relates to the field of aluminum alloys, and in particular to an aluminum alloy strip for batteries and a preparation method thereof.

Background technique

In recent years, aluminum alloy strips have gradually replaced the original battery shells due to their excellent comprehensive machining performance, good corrosion resistance, light specific gravity, good heat dissipation performance and strong anti-electromagnetic interference performance. Materials - plastic PV and PVC materials, the market prospects for aluminum alloy strips for battery cases will be very broad.

Since the preparation of the battery case is an asymmetric type stamping, and there are large deformation, large number of punching processes and complicated punching process in the preparation process, the aluminum alloy strip is ensured under the premise of ensuring necessary plasticity. There must also be sufficient strength. The aluminum alloy strip currently used for batteries still cannot meet the requirements of the battery shell preparation process, and has quality defects such as poor punching performance and low molding rate.

Summary of the invention

The technical problem mainly solved by the present application is to provide an aluminum alloy strip for a battery and a preparation method thereof, which can effectively solve the above-mentioned deficiencies of the existing aluminum battery.

In order to solve the above technical problem, a technical solution adopted in the present application is to provide an aluminum alloy strip for a battery, comprising the following alloy components by weight: Si 0.71 to 0.75%, Fe 0.65 to 0.68%, Cu 0.11 ～0.14%, Mn 0.060 to 0.068%, Mg 0.040 to 0.048%, Cr 0.060 to 0.065%, Zn ≤ 0.03%, Ti 0.035 to 0.040%, and the balance being Al.

In a preferred embodiment of the present application, the aluminum alloy strip has a thickness of 0.5 to 2 mm.

In order to solve the above technical problem, another technical solution adopted by the present application is to provide a method for preparing an aluminum alloy strip for a battery, comprising the following steps:

(1) alloy smelting: the alloy ingot of the above formula amount is placed in molten aluminum, and heated and smelted in an inert gas atmosphere;

(2) hot rolling into a billet: the alloy material after the smelting in step (1) is added to a rolling mill, and rolled into a billet of D1 thickness under heating;

(3) aging treatment: the hot-rolled blank in step (2) is placed in the environment for aging treatment for more than 6h;

(4) Cold rolling and annealing treatment: the billet after the homogenization annealing in the step (3) is subjected to three cold rolling treatments and three annealing treatments, and each of the cold rolling treatments is directly subjected to annealing treatment, and then the next cold rolling is performed. Processing, the thickness of the blank obtained after three cold rolling is D2, D3 and D4;

(5) Aging treatment: The blank after three times of cold rolling and three annealing treatment in step (4) is placed in a natural environment for aging treatment for more than 12 hours, and then subjected to shearing application.

In a preferred embodiment of the present application, in the step (1), the heating smelting process conditions are: a nitrogen atmosphere, a temperature of 550 to 600 ° C, a time of 7.5 to 8 h, and a tapping temperature of 520 to 525 ° C.

In a preferred embodiment of the present application, in the step (2), the hot rolling temperature is 320 to 280 ° C, and the D1 is 8 to 10 mm.

In a preferred embodiment of the present application, in the step (4), the three annealing conditions are: 380-420 ° C, 15-20 h; 300-350 ° C, 10-13 h; 240-280 ° C , 8 ~ 10h.

In a preferred embodiment of the present application, in the step (4), the D2 is 4-6 mm; the D3 is 1-4 mm; and the D4 is 0.5-2 mm.

The beneficial effects of the present application are as follows: the aluminum alloy strip for battery of the present application is designed by a reasonable alloy distribution ratio design and a hot rolling, aging treatment, cold rolling, annealing treatment and aging treatment molding process, so that the preparation is obtained. The tensile strength, elongation and punching performance of the aluminum alloy strip are remarkably improved, thereby increasing the forming rate of the battery shell for stamping. The aluminum alloy strip of the present application is an ideal strip for preparing an aluminum alloy battery. The field of aluminum alloy batteries has broad application prospects.

detailed description

The preferred embodiments of the present application are explained in detail below to make the advantages and features of the present application more readily understood by those skilled in the art, so that the scope of protection of the present application is more clearly and clearly defined.

Embodiments of the application include:

Example 1

The present application discloses an aluminum alloy strip for a battery, the aluminum alloy strip having a thickness of 0.5 to 1 mm, the aluminum alloy strip comprising the following alloy components by weight: Si 0.71%, Fe 0.65% Cu 0.11%, Mn 0.06%, Mg 0.04%, Cr 0.06%, Zn ≤ 0.03%, Ti 0.035% and the balance is Al.

The method for preparing the above aluminum alloy strip for a battery includes the following steps:

(1) Alloy melting: an aluminum alloy ingot containing the above-mentioned formula alloy is placed in a melting furnace, and smelted in a heating furnace at a temperature of 550 ° C for 8 hours in an inert gas nitrogen atmosphere, and slightly cooled to 520 ° C. Baked out

(2) hot-rolled into a billet: the aluminum alloy material after the melting in step (1) is added to a rolling mill, and rolled to a thickness of D1 under a heating condition of 280 ° C; the D1 is 8 to 10 mm;

(3) aging treatment: the hot-rolled blank in step (2) is placed in an indoor environment of about 25 ° C for aging treatment for more than 6h;

(4) Cold rolling and annealing treatment: the billet after the aging treatment in the step (3) is subjected to three cold rolling treatments and three annealing treatments, and each of the cold rolling treatments is directly subjected to annealing treatment, and then subjected to the next cold rolling treatment. The thickness of the blank obtained after three times of cold rolling is D2, D3 and D4, respectively;

Specifically, the first cold rough rolling treatment is first performed in the rolling mill, so that the thickness of the blank reaches D2 of 4 to 5 mm; then annealing treatment is performed, and the annealing process conditions are: 380 ° C, 15 h;

After annealing, a second cold-rolling process is performed to make the thickness of the blank reach D3 of 1 to 3 mm; then annealing is performed, and the annealing process conditions are: 300 ° C, 10 h;

After the annealing treatment, the third cold finish rolling treatment is performed, so that the thickness of the billet reaches D4 of 0.5 to 1 mm; then annealing treatment is performed, and the annealing process condition is: 240 ° C, 8 h;

(5) Aging treatment: The blank after three times of cold rolling and three annealing treatment in step (4) is placed in a natural environment for aging treatment for more than 12 hours, and then subjected to cutting application.

Example 2

The application discloses an aluminum alloy strip for a battery, the aluminum alloy strip has a thickness of 1 to 2 mm, and the aluminum alloy strip comprises the following alloy components by weight percentage: Si 0.75%, Fe 0.68% Cu 0.14%, Mn 0.068%, Mg 0.048%, Cr 0.065%, Zn ≤ 0.03%, Ti 0.04% and the balance is Al.

(1) Alloy smelting: An aluminum alloy ingot containing the alloy of the above formula amount is placed in a melting furnace, and smelting is performed in a heating furnace at a temperature of 600 ° C for 7.5 hours in an inert gas nitrogen atmosphere, and is slightly cooled to 525. °C baked;

(2) hot-rolled into a billet: the aluminum alloy material after the smelting in step (1) is added to a rolling mill, and rolled into a D1 thickness billet under heating conditions of 320 ° C; the D1 is 8 to 10 mm;

Specifically, the first cold rough rolling treatment is performed in the rolling mill to make the thickness of the blank reach D2 of 5-6 mm; then annealing treatment is performed, and the annealing process condition is: 420 ° C, 20 h;

After the annealing treatment, the second cold-rolling treatment is performed, so that the thickness of the billet reaches D3 of 2 to 4 mm; then annealing treatment is performed, and the annealing process conditions are: 350 ° C, 13 h;

After the annealing treatment, the third cold finish rolling treatment is performed, so that the thickness of the blank reaches D4 is 1 to 2 mm; then annealing treatment is performed, and the annealing process condition is: 280 ° C, 10 h;

The aluminum alloy strip prepared by the above method has been tested to have a tensile strength of 200 to 215 MPa, an elongation of ≥3.0%, and an impact toughness value of 8.9 to 9.5 J/cm ² , which improves the molding rate of the battery prepared therefrom. There are materials that increase by more than 20%.

The invention relates to an aluminum alloy strip for a battery, which is designed by a reasonable alloy distribution ratio design and a hot rolling, cold rolling, annealing treatment and a two-aging treatment process, so that the prepared aluminum alloy strip is tensile. The strength and elongation are significantly improved, the punching performance is good and the forming rate is high, which is an ideal strip for preparing aluminum alloy batteries, and has broad application prospects in the field of aluminum alloy batteries.

The above description is only the preferred embodiment of the present application, and is not intended to limit the present application, and various changes and modifications may be made to the present application. Any modifications, equivalent substitutions, and improvements made within the spirit and scope of the present application are intended to be included within the scope of the present application.

Claims

An aluminum alloy strip for a battery, comprising: an alloy composition of the following weight percentage: Si 0.71 to 0.75%, Fe 0.65 to 0.68%, Cu 0.11 to 0.14%, Mn 0.06 to 0.068%, Mg 0.04 ～0.048%, Cr 0.06 to 0.065%, Zn ≤ 0.03%, Ti 0.035 to 0.04%, and the balance is Al.
The aluminum alloy strip for a battery according to claim 1, wherein the aluminum alloy strip has a thickness of 0.5 to 2 mm.
A method for preparing an aluminum alloy strip for a battery according to claim 1, comprising the steps of:

(1) alloy smelting: an alloy ingot containing the formulation amount according to claim 1 is placed in molten aluminum, and heated and smelted in an inert gas atmosphere;

(2) hot rolling into a billet: the alloy material after the smelting in step (1) is added to a rolling mill, and rolled into a billet of D1 thickness under heating;

(3) aging treatment: the hot-rolled blank in step (2) is placed in the environment for aging treatment for more than 6h;

(4) Cold rolling and annealing treatment: the billet after the aging treatment in the step (3) is subjected to three cold rolling treatments and three annealing treatments, and each of the cold rolling treatments is directly subjected to annealing treatment, and then subjected to the next cold rolling treatment. The thickness of the blank obtained after three times of cold rolling is D2, D3 and D4, respectively;

(5) Aging treatment: The blank after three times of cold rolling and three annealing treatment in step (4) is placed in a natural environment for aging treatment for more than 12 hours, and then subjected to cutting application.
The method for preparing an aluminum alloy strip for a battery according to claim 3, wherein in the step (1), the heating smelting process condition is: a nitrogen atmosphere, a temperature of 550 to 600 ° C, and a time of 7.5. ~8h, the tapping temperature is 520 ~ 525 °C.
The method for producing an aluminum alloy strip for a battery according to claim 3, wherein in the step (2), the hot rolling temperature is 320 to 280 ° C, and the D1 is 8 to 10 mm.
The method for preparing an aluminum alloy strip for a battery according to claim 3, wherein in the step (4), the three annealing conditions are: 380 to 420 ° C, 15 to 20 h; 300 to 350 ° C, 10 ~ 13h; 240 ~ 280 ° C, 8 ~ 10h.
The method for preparing an aluminum alloy strip for a battery according to claim 3, wherein in the step (4), the D2 is 4 to 6 mm; the D3 is 1 to 4 mm; and the D4 is 0.5. ~2mm.