JP5971851B2 - Aluminum alloy plate for aerosol can body and manufacturing method thereof - Google Patents

Description

  The present invention relates to an aluminum alloy plate for an aerosol can body and a method for producing the same.

Aerosol cans contain a mixture of contents such as medicines and propellant in a hermetically sealed state, and when in use, the injection valve is opened so that the contents are mist-like or foamy with the pressure of the propellant in the can. Is to be injected. Aerosol cans are used as containers for a wide variety of products such as deodorants, cosmetics, cleaners, pharmaceuticals, and paints.
As the material of such an aerosol can body, an aluminum alloy such as an Al—Mn alloy has been used so far (see, for example, Patent Document 1).

  The aerosol can body is obtained by forming an aluminum alloy plate into a can body shape by DI (Drawing and Ironing) processing, which is performed by combining drawing processing and ironing processing. Various characteristics such as pressure resistance, corrosion resistance, and low ear rate are required as characteristics required for an aluminum alloy plate for an aerosol can body. Recently, in order to reduce the weight of aerosol cans and save aluminum resources, the thickness of aerosol can bodies has been reduced.

JP 2008-169417 A

  However, when the thickness of the aerosol can body is reduced, it is difficult to ensure sufficient pressure resistance with the conventional aluminum alloy plate. Further, in the conventional aluminum alloy plate, if it is thin, the ear rate becomes high at the time of drawing and the like, and as a result, not only is the material wasted, but also the broken body and pinhole due to the ear cut. There is a risk of problems such as occurrence.

  The present invention has been made against the background of the above circumstances, and has an object to provide an aluminum alloy plate for an aerosol can body having high pressure resistance, low ear rate, and capable of being thinned, and a method for manufacturing the same. To do.

The method for producing an aluminum can plate for an aerosol can body according to the first aspect of the present invention is to homogenize an ingot of JIS A3104 alloy having a Mg content of 1.1% by mass or less, and then hot rolling, Thereafter, cold rolling is performed, and at least one intermediate annealing is performed at an ultimate temperature of 505 to 565 ° C. using a continuous annealing furnace, and in the final cold rolling until the final sheet thickness is reached after the final intermediate annealing. The rolling rate is 8 to 18%.

The method for producing an aluminum can plate for an aerosol can body according to the second aspect of the present invention is characterized in that, in the first aspect of the present invention, the stabilization annealing is performed after the final cold rolling.

The method for producing an aluminum alloy plate for an aerosol can body according to the third aspect of the present invention is characterized in that, in the second aspect of the present invention, the stabilizing annealing is performed under conditions of 190 to 210 ° C. × 1 to 4 hours. .

  The reasons for limiting the components of the aluminum alloy plate for aerosol cans of the present invention will be described. In addition, all the following contents are shown by the mass%.

JIS A3104 alloy The aluminum alloy constituting the aluminum alloy plate for an aerosol can body of the present invention has a Mg content of 1.1% or less in the JIS A3104 alloy.
JIS A3104 alloy has Si: 0.6% or less, Fe: 0.8% or less, Cu: 0.05-0.25%, Mn: 0.8-1.4%, Mg: 0.8-1 .3%, with the balance being composed of Al and inevitable impurities.
The JIS A3104 alloy may contain Zn in an amount of 0.25% or less and Ti in an amount of 0.1% or less, and optionally contain Ga, V, Ni, B, or Zr of 0.05% or less. Inevitable impurities may be contained individually by 0.05% or less, and the total amount may be 0.15% or less.

Mg: 1.1% or less Mg is an element necessary for improving the strength of an aluminum alloy. However, when the Mg content exceeds 1.1 mass% in the JIS A3104 alloy, the workability deteriorates. As a result, the ear rate is increased. For this reason, the content of Mg is limited to 1.1% by mass or less as described above. Thereby, even if it is a JIS A3104 aluminum alloy, the workability of an aluminum alloy plate will become favorable, and an ear | edge rate can be suppressed low.
For the same reason, the Mg content is desirably 0.85% or more, and desirably 0.95% or less.

Plate thickness: 0.6-0.8mm
The aluminum alloy plate for an aerosol can body of the present invention is limited to a plate thickness of 0.6 to 0.8 mm. In addition, from the viewpoint of ensuring high pressure resistance, the thickness of the aluminum alloy plate is preferably 0.65 mm or more, and more preferably 0.7 mm or more.

Ear ratio: 2% or less By achieving an ear ratio of 2% or less in the above plate thickness, both weight reduction and DI processability can be achieved. In the deep drawing test, the ear rate in the present invention is a ratio (%) obtained by dividing the difference between the average peak height and the average valley height when the drawing ratio is 1.67 by the average valley height. Represent.

  Next, the reason for limiting the conditions in the production method of the present invention will be described.

Homogenizing treatment By homogenizing the aluminum alloy ingot having the above composition, the transformation of the precipitate into the α-Al (Fe, Mn) Si phase is promoted and the drawability is improved.
In addition, although the conditions of a homogenization process are not limited to a specific thing as this invention, For example, 540-580 degreeC * 5 to 10 hours are shown as a suitable thing.

Hot rolling Hot rolling can be carried out in a conventional manner, and the present invention is not limited to specific conditions, but suitable conditions include hot rolling and subsequent cold rolling. Then, the hot rolling finish temperature of 300 degreeC or more is preferable.
The finished sheet thickness of the aluminum alloy sheet by hot rolling is desirably 3 to 8 mm. This is because if it is less than 3 mm, the cold rolling rate is low and sufficient mechanical properties cannot be obtained, and if it exceeds 8 mm, the cold rolling rate increases and the ear rate deteriorates.
Moreover, it is desirable to determine the rolling rate in hot rolling so that the cold rolling rate after hot rolling exceeds 70%.

Cold rolling Although cold rolling can be performed by a conventional method, it is desirable to perform at least one intermediate annealing before cold rolling or during cold rolling. When intermediate annealing is performed only during the cold rolling, it is desirable that the cold rolling rate before the first intermediate annealing is more than 70%. By setting the cold rolling rate to more than 70%, the mechanical properties after the final plate and the can can be improved, and high pressure resistance can be secured.
Note that the cold rolling rate in the final cold rolling after the final intermediate annealing to the final plate thickness is limited to 8 to 18%.
When the cold rolling rate is less than 8%, the strength of the aluminum alloy sheet is insufficient. On the other hand, when the final cold rolling rate exceeds 18%, the ear rate increases. For this reason, the said cold rolling rate is prescribed | regulated. For the same reason, the cold rolling rate is desirably 10% or more, and desirably 14% or less.

Intermediate annealing Intermediate annealing performed at least once before the cold rolling or in the middle of cold rolling is performed at an ultimate temperature of 505 to 565 ° C using a continuous annealing furnace.
By making the ultimate temperature during intermediate annealing 505 ° C. or higher, a solution effect can be expected, and if the ultimate temperature during intermediate annealing exceeds 565 ° C., the material may be melted. In this case, the temperature reached is 565 ° C. or lower.
For the same reason, the ultimate temperature during the intermediate annealing is preferably 530 ° C. or higher, and preferably 550 ° C. or lower.
Further, in the intermediate annealing, in order to obtain a solution effect, it is desirable that the temperature is raised from room temperature to a set temperature when the temperature is raised, and that the temperature is 10 minutes or less from the maximum temperature to 100 ° C. when the temperature is cooled.

Stabilization annealing Stabilization annealing may be performed after the final cold rolling. By performing the stabilization annealing, the occurrence of bottom-out can be reduced when performing DI processing on the aluminum alloy plate.
The conditions of stabilization annealing can show the conditions of 190-210 degreeC x 1-4 hours as a suitable thing. If the annealing temperature is less than 190 ° C, the bottoming out improvement effect cannot be obtained.

As explained above, according to the aluminum alloy plate for an aerosol can body of the present invention, it is made of a JIS A3104 alloy having a Mg content of 1.1% by mass or less, and the plate thickness is 0.6 to 0.8 mm. Since the ear rate is 2% or less, even with a thin wall, it has high pressure resistance and excellent DI processability.
Further, according to the method for producing an aluminum alloy plate for an aerosol can body of the present invention, a hot rolling is performed after homogenizing the ingot of JIS A3104 alloy having a Mg content of 1.1% by mass or less. Then, cold rolling is performed, and at least one intermediate annealing is performed at an ultimate temperature of 505 to 565 ° C. using a continuous annealing furnace, and after the final intermediate annealing, final cold rolling is performed until the final plate thickness is reached. Therefore, the aluminum alloy plate for an aerosol can body can be manufactured with high pressure resistance and low ear rate.

Hereinafter, an aluminum alloy plate for an aerosol can body and a manufacturing method thereof according to an embodiment of the present invention will be described.
The aluminum alloy plate for aerosol can bodies of the present embodiment is a JIS A3104 aluminum alloy, and has a Mg content of 1.1 mass% or less. The aluminum alloy constituting the aluminum alloy plate is, for example, in mass%, Si: 0.2 to 0.35%, Fe: 0.35 to 0.55%, Cu: 0.05 to 0.25%, It contains Mn: 0.8 to 1.15%, Mg: 0.8 to 1.1%, and the balance is composed of Al and inevitable impurities.

  Moreover, the aluminum alloy plate for aerosol can bodies of the present embodiment has a thin thickness of 0.6 to 0.8 mm.

  Moreover, the aluminum alloy plate for aerosol can bodies of this embodiment has an ear rate of 2% or less. In addition, in the deep drawing test, the ear rate mentioned here is a ratio (%) obtained by dividing the difference between the average peak height and the average valley height when the drawing ratio is 1.67 by the average valley height. ) Is the measured value.

Next, the manufacturing method of the said aluminum alloy plate for aerosol can bodies is demonstrated.
An ingot of an aluminum alloy as a material for an aluminum can plate for an aerosol can body can be cast by a conventional method. For example, the ingot can be obtained by adjusting the components so as to be within the above component range and casting.

Next, a homogenization treatment is performed on the ingot of the obtained aluminum alloy. A homogenization process is performed on the conditions of 540-580 degreeC x 5 to 10 hours, for example, and hot rolling is performed after a homogenization process. The conditions for hot rolling are controlled, for example, as the hot finish temperature between 300 and 350 ° C.
In the hot rolling, it is preferable that the finished plate thickness of the aluminum alloy plate is 3 to 8 mm. In addition, it is desirable to set the finished sheet thickness so that the cold rolling rate after the hot rolling to the first intermediate annealing exceeds 70%.

After the hot rolling, cold rolling is performed on the hot rolled material.
Further, at least one intermediate annealing is performed before or during the cold rolling.
A continuous annealing furnace is used as the annealing furnace for intermediate annealing, and the annealing conditions are preferably, for example, an ultimate temperature of 505 to 565 ° C., a temperature rising time, and a cooling time of 10 minutes or less.

When intermediate annealing is performed only during the cold rolling, it is desirable that the cold rolling is performed so that the cold rolling rate before the first intermediate annealing exceeds 70%, and the final thickness is reached after the final intermediate annealing. The final cold rolling reduction to 8 to 18%.
Thereby, an aluminum alloy plate having a thickness of 0.6 to 0.8 mm is obtained. The aluminum alloy plate has an ear rate of 2% or less.
In addition, after the said last cold rolling, stabilization annealing is implemented with respect to an aluminum alloy plate. The conditions for stabilization annealing are, for example, 190 to 210 ° C. × 1 to 4 hours.

Examples of the present invention will be described below.
First, an aluminum alloy ingot was obtained by melting an aluminum alloy so as to have a composition shown in Table 1 (the balance being Al and inevitable impurities). Next, homogenization was performed at 565 ° C. for 7 hours, and hot rolling was performed so that the finished plate thickness shown in Table 1 was obtained.
Further, while performing cold rolling, intermediate annealing and final cold rolling according to the manufacturing conditions shown in Table 1 were performed in the middle to obtain aluminum alloy plates of the respective test materials with plate thicknesses of 0.75 and 0.67 mm. It was.
Table 1 shows the cold rolling ratio until the first intermediate annealing, the intermediate annealing conditions, and the plate thickness at the time of the final intermediate annealing. In these test materials, the intermediate annealing was performed once.
The specimens of Examples 3 to 6 were further subjected to stabilization annealing at 180, 190, 200, 220 ° C. × 2 hours after the final cold rolling.

  About the aluminum alloy plate of each said test material, each characteristic of the ear | edge rate, bottom-out resistance, and pressure-resistant strength was evaluated as follows.

(Ear rate)
About the aluminum alloy plate of each test material, it is drawn at a drawing ratio of 1.67, and the ratio of the obtained cup divided by the average of the valley height divided by the average of the peak height and the average of the valley height Ear rate was measured as (%).

(Bottom resistance)
200 aluminum cans having a diameter of 53 mm and a height of 170 mm were made by DI processing for each test material aluminum alloy plate, and the bottom resistance was evaluated according to the following criteria. The can was made by DI molding with a drawing ratio of 2.2.
○: There was no bottom can 1 △: There were 1 to 3 bottoms ×: There were 4 or more bottoms

(Pressure strength)
For each specimen, pressurize the aerosol can obtained above to increase the pressure, measure the pressure when the aerosol can deforms, and determine the average value of 3 cans for each specimen. Strength (MPa) was used.

As shown in Table 1, the material of the present invention exhibited good characteristics in terms of ear rate, bottom resistance, and pressure resistance. In Example 3, since the stabilization annealing temperature is 180 ° C., the bottoming resistance is slightly inferior. In addition, Examples 7 to 9 are slightly inferior in bottom resistance. In Example 6, since the stabilization annealing temperature is 220 ° C., the pressure resistance and the ear rate are slightly poor.
On the other hand, the comparative material which does not satisfy the above-described conditions of the present invention has a high Mg content and a low bottom resistance and a poor ear rate in Comparative Examples 1 to 3.

Claims (3)

  An ingot of JIS A3104 alloy having a Mg content of 1.1 mass% or less is homogenized, then hot rolled, then cold rolled, and at least one intermediate annealing is performed continuously. For an aerosol can body, characterized in that the rolling rate in the final cold rolling until the final sheet thickness is 8 to 18% after the final intermediate annealing is performed at an ultimate temperature of 505 to 565 ° C. using a furnace A method for producing an aluminum alloy plate. The process according to claim 1 aerosol can body aluminum alloy plate according to characterized in that a stabilizing annealing after rolling the final cold. The said stabilization annealing is performed on the conditions of 190-210 degreeC x 1 to 4 hours, The manufacturing method of the aluminum alloy plate for aerosol can bodies of Claim 2 characterized by the above-mentioned.