JP6685106B2 - Aluminum alloy foil - Google Patents

Description

  The present invention relates to an aluminum alloy foil, a container formed by molding the aluminum alloy foil, and a method for manufacturing the aluminum alloy foil.

As a baking mold for baking contents such as confectionery and bread, a container formed from an aluminum alloy foil is used as in Patent Document 1.
The strength of such a container tends to decrease due to the heat applied during the baking of the contents, so it can withstand repeated use by being bent or deformed when taking out the contents. could not.

For example, when the content is confectionery or bread, the baking temperature is generally 150 to 200 ° C. and the baking time is generally 15 to 30 minutes. When baking bread or bread and taking out the baked confectionery or bread from the container, the container is likely to bend or deform due to the applied force.
Therefore, it is impossible to reuse the container at the time of subsequent firing, and the container is thrown away after each firing, resulting in a high cost.

JP, 2000-079934, A

By devising the properties of the aluminum alloy foil that is the material of the container, it is possible to suppress the decrease in the strength of the container during baking of the contents, and if the container can be reused multiple times, the cost of baking the contents Can be reduced.
For example, when the content is confectionery or bread, there is a demand from the industry that the cost can be significantly reduced if the container can be reused about 4 to 5 times.

  Therefore, the problem to be solved by the present invention is to obtain desired heat resistance characteristics of the aluminum alloy foil as the material of the container so that the container can withstand repeated use.

In order to solve the above-mentioned problems, as the aluminum alloy foil according to the present invention, the tensile strength is kept at 120 N / mm ² or more and the elongation is 2.0% or more even after being softened at 150 ° C. for 240 minutes. It has a tensile strength of 100 N / mm ² or more and has an elongation of 3.0% or more even if it is softened at 180 ° C for 240 minutes, and it is softened at 200 ° C for 240 minutes. Even after the treatment, a structure was adopted in which the tensile strength was maintained at 90 N / mm ² or more and the elongation was 3.0% or more.

  By configuring the aluminum alloy foil according to the present invention as described above, even when the contents are used as a container for baking at a general temperature and time, when the contents are taken out after baking, Sufficient strength that can prevent bending and deformation can be maintained.

  The aluminum alloy foil according to the present invention comprises 0.3% by mass or more and 3.0% by mass or less of iron, 0.8% by mass or more and 1.5% by mass or less of silicon, and 0.0001% by mass or more and 0.011% or more. Mass% or less copper, 0.0001 mass% or more and 0.6 mass% or less manganese, 0.0001 mass% or more and 0.011 mass% or less magnesium, and 0.001 mass% or more 0.011 mass% What contains the following zinc, 0.005 mass% or more and 0.5 mass% or less titanium, and 0.0001 mass% or more and 0.3 mass% or less zirconium, with the balance being aluminum and unavoidable impurities preferable.

  By configuring the aluminum alloy foil according to the present invention with the above composition, it is possible to suppress the generation of large-diameter crystallized substances in the alloy, and it is possible to contribute to the realization of a foil having sufficient strength.

  The aluminum alloy foil according to the present invention is preferably subjected to intermediate annealing at 300 ° C. or higher and 400 ° C. or lower when rolled into a thickness of 0.5 to 1.2 mm after continuous casting. The thickness is preferably 5 to 100 μm.

  By configuring the aluminum alloy foil according to the present invention through the heat treatment as described above, it is possible to surely obtain a foil having a balanced tensile strength and elongation.

The container according to the present invention is preferably made of the above aluminum alloy foil.
It is needless to say that the alloy foil according to the present invention can be used for applications other than containers for electronic parts and the like.

  The aluminum alloy foil according to the present invention comprises 0.3% by mass or more and 3.0% by mass or less of iron, 0.8% by mass or more and 1.5% by mass or less of silicon, and 0.0001% by mass or more and 0.011% or more. Mass% or less copper, 0.0001 mass% or more and 0.6 mass% or less manganese, 0.0001 mass% or more and 0.011 mass% or less magnesium, and 0.001 mass% or more 0.011 mass% An aluminum alloy containing the following zinc, 0.005 mass% or more and 0.5 mass% or less titanium, and 0.0001 mass% or more and 0.3 mass% or less zirconium, with the balance being aluminum and inevitable impurities. And a step of forming the aluminum alloy into an aluminum alloy piece by continuous casting, and the aluminum alloy piece is formed into an aluminum alloy plate having a thickness of 0.5 mm to 1.2 mm. It is preferable to include a step of rolling, a step of performing intermediate annealing at 300 to 400 ° C. in an intermediate step of the sheet rolling, and a step of foil rolling the aluminum alloy sheet to an aluminum alloy foil having a thickness of 5 to 100 μm. .

  Since the aluminum alloy foil according to the present invention is configured as described above, even if it is softened at a predetermined temperature and time, sufficient strength is maintained, and therefore, when molded into a container, it can be used for baking work of the contents. Can withstand repeated use.

Graph showing tensile strength characteristics of aluminum alloy foil after heating at 150 ° C Graph showing elongation characteristics of aluminum alloy foil after heating at 150 ° C Graph showing tensile strength characteristics of aluminum alloy foil after heating at 180 ° C Graph showing elongation characteristics of aluminum alloy foil after heating at 180 ° C Graph showing tensile strength characteristics of aluminum alloy foil after heating at 200 ° C Graph showing elongation characteristics of aluminum alloy foil after heating at 200 ° C

The aluminum alloy foil according to the embodiment of the present invention will be described below.
The aluminum alloy foil of the embodiment has the following tensile strength and elongation characteristics when subjected to the softening treatment at 150 ° C to 200 ° C.
When softened at 150 ° C. for 240 minutes, the tensile strength is maintained at 120 N / mm ² or more and the elongation is 2.0% or more.
When subjected to a softening treatment at 180 ° C. for 240 minutes, the tensile strength is maintained at 100 N / mm ² or more, and the elongation is 3.0% or more.
When softened at 200 ° C. for 240 minutes, the tensile strength is maintained at 90 N / mm ² or more and the elongation is 3.0% or more.
The aluminum alloy foil of the embodiment having such characteristics can be obtained, for example, by manufacturing an aluminum alloy foil having the following composition by the manufacturing method of the following embodiment.

The composition of the aluminum alloy foil of the embodiment is not particularly limited, but the following composition is preferable.
It contains iron (Fe) in an amount of 0.3% by mass or more and 3.0% by mass or less.
It contains 0.8 mass% or more and 1.5 mass% or less of silicon (Si).
It contains 0.0001% by mass or more and 0.011% by mass or less of copper (Cu).
Includes 0.0001% by mass or more and 0.6% by mass or less of manganese (Mn).
It contains 0.0001% by mass or more and 0.011% by mass or less of magnesium (Mg).
It contains 0.001% by mass or more and 0.011% by mass or less of zinc (Zn).
Includes 0.005% by mass or more and 0.5% by mass or less of titanium (Ti).
It contains 0.0001% by mass or more and 0.3% by mass or less of zirconium (Zr).
The balance consists of aluminum (Al) and inevitable impurities.

In the above composition, iron crystallizes in the aluminum alloy as an Al-Fe-based compound and contributes to the improvement of the elongation of the aluminum alloy foil.
If the iron content is less than 0.3% by mass, the effect of improving elongation may not be sufficiently obtained.
On the other hand, when the iron content exceeds 3.0 mass%, the Al—Fe-based compound is excessively crystallized, so that the tensile strength is excessively increased, which may rather lower the elongation.

In the above composition, silicon contributes to the improvement of the tensile strength of the aluminum alloy foil.
When the content of silicon is less than 0.8% by mass, the effect of improving tensile strength may not be sufficiently obtained.
If the silicon content exceeds 1.5% by mass, the tensile strength may increase excessively and the elongation may decrease.

In the above composition, copper is likely to form a solid solution in aluminum and reduces the elongation of the aluminum alloy foil.
Therefore, it is preferable to limit the content of copper to 0.011% by mass or less. The more preferable content of copper is 0.005 mass% or less. The lower limit of the copper content is not particularly limited, but is usually about 0.0001 mass%.

In the above composition, manganese contributes to improvement in tensile strength and elongation of the aluminum alloy foil.
However, excessive crystallization of the Al-Mn-based compound in the aluminum alloy may excessively increase the tensile strength of the aluminum alloy foil, which may rather reduce the elongation of the aluminum alloy foil. Therefore, it is preferable to limit the content of manganese to 0.6% by mass or less. The lower limit of the manganese content is not particularly limited, but is usually about 0.0001 mass%.

In the above composition, magnesium easily forms a solid solution in aluminum and reduces the elongation of the aluminum alloy foil.
Therefore, it is preferable to limit the content of magnesium to 0.011% by mass or less. The more preferable content of magnesium is 0.005 mass% or less. The lower limit of the magnesium content is not particularly limited, but is usually about 0.0001 mass%.

In the above composition, zinc contributes to the improvement of the tensile strength and the elongation of the aluminum alloy foil, but significantly reduces the corrosion resistance of the aluminum alloy foil.
Therefore, it is preferable to limit the zinc content to 0.011% by mass or less. The lower limit of the zinc content is not particularly limited, but is usually about 0.001% by mass.

In the above composition, titanium contributes to improvement of tensile strength and elongation of the aluminum alloy foil.
When the content of titanium is less than 0.005 mass%, the effect of improving tensile strength and elongation may not be sufficiently obtained.
If the content of titanium exceeds 0.5% by mass, the tensile strength of the aluminum alloy foil may be excessively increased and the elongation may be reduced.

In the above composition, zirconium contributes to improvement in tensile strength and elongation of the aluminum alloy foil.
If the content of zirconium is less than 0.0001% by mass, the effect of improving tensile strength and elongation may not be sufficiently obtained.
If the content of zirconium exceeds 0.3% by mass, the tensile strength of the aluminum alloy foil may be excessively increased and the elongation may be reduced.

The thickness of the aluminum alloy foil of the embodiment is not particularly limited, but is preferably 5 to 100 μm.
When the thickness is less than 5 μm, pinholes (holes) may occur, and when the thickness exceeds 100 μm, the strength of the foil is too high and the formability may deteriorate.

The manufacturing method of the aluminum alloy foil of the embodiment is not particularly limited, but the following manufacturing method is preferable.
First, an aluminum alloy having the above composition is prepared.
This aluminum alloy is cast by a known continuous casting method to obtain a plate-shaped aluminum alloy piece having a thickness of 6 mm.
Then, the aluminum alloy piece is rolled by a known cold rolling method to obtain an aluminum alloy sheet having a thickness of 0.5 to 1.2 mm.
Further, the aluminum alloy plate is foil-rolled by a known cold rolling method to obtain an aluminum alloy foil according to the embodiment having a thickness of 5 to 100 μm.

In the method for manufacturing the aluminum alloy foil of the embodiment, further, during the plate rolling step, intermediate annealing is performed at an annealing temperature of 300 to 400 ° C. and an annealing time of 2 to 48 hours.
Although not particularly limited, an aluminum alloy plate having a thickness of 1.2 mm is subjected to intermediate annealing at 170 ° C. and 400 ° C. for 5 hours, and an aluminum alloy plate having a thickness of 0.5 mm is heated at 300 ° C. and 500 ° C. It can be illustrated that the intermediate annealing is performed for 5 hours. The atmosphere of the intermediate annealing was performed in an air atmosphere, but may be performed in an inert gas or vacuum atmosphere.
It can be illustrated that the aluminum alloy sheet after the intermediate annealing is rolled to a thickness of 75 μm in the subsequent foil rolling step.
By the intermediate annealing, the final balance of tensile strength and elongation of the aluminum foil is adjusted to the optimum balance that can withstand repeated use when the container formed by molding the foil is used for firing the contents. It becomes easy to arrange.
If the annealing temperature is lower than 300 ° C. or the annealing time is shorter than 2 hours, the temperature may not be raised to the core when processing a coil-shaped aluminum foil of 500 kg or more. If the annealing temperature exceeds 400 ° C. or the annealing time exceeds 48 hours, the tensile strength outside the winding may be insufficient.

The container of the embodiment is obtained by forming the aluminum alloy foil of the embodiment by a known forming method such as pressing.
The use of the container of the obtained embodiment is not particularly limited, but it is suitable for use as a container when baking confectionery or bread in an oven or the like.
From the tensile strength and elongation characteristics of the aluminum alloy foil of the embodiment as described above, the container has sufficient strength, it is suppressed that the container is bent or deformed when taking out the bread, etc. It can be reused for subsequent firing operations. Therefore, it is possible to contribute to the reduction of the manufacturing cost of bread and the like.
The shape of the container is not particularly limited, but it is exemplified by a bottom wall having a circular shape in plan view, a peripheral wall rising from the peripheral edge of the bottom wall, a flange extending horizontally from the peripheral edge of the peripheral wall, and a curb attached to the outer edge of the flange. it can.
The use of the aluminum alloy of the embodiment is not limited to a container, and is suitably used for forming a molded body other than a container such as an electronic component.

  Hereinafter, the present invention will be further clarified with reference to Examples and Comparative Examples.

As Example 1 to Example 3, aluminum alloy pieces obtained by continuous casting with the alloy composition shown in Table 1 below were subjected to sheet annealing and then subjected to intermediate annealing at a temperature of 300 ° C. for 5 hours at a thickness of 0.5 mm to obtain a thickness of 75 μm. A thick aluminum alloy foil was obtained.
Further, as Examples 4 to 6, aluminum alloy pieces obtained by continuous casting with the alloy compositions shown in the following Table 1 were subjected to sheet annealing, and were subjected to intermediate annealing at a temperature of 400 ° C. for 5 hours at a thickness of 1.2 mm to 75 μm. An aluminum alloy foil having a thickness of
In addition, the range of each element in the following Table 1 defines the range of the chemical composition in consideration of process capability in alloy preparation in a large melting furnace as the range of claim 2 in the claims.

  Further, as Examples 7 to 9, aluminum alloy pieces having an alloy purity of 1N30 (JIS H 4160-1994) and obtained by continuous casting were subjected to plate rolling at a thickness of 0.5 mm at a temperature of 300 ° C. for 5 hours. Intermediate annealing was performed to obtain an aluminum alloy foil having a thickness of 75 μm.

The aluminum alloy foils of Examples 1 to 9 were formed by deep drawing into a baking container having an opening outer diameter of 75 mm, a bottom diameter of 50 mm, and a height of 50 mm and having a circular shape in plan view.
Bread dough was placed in this container, and bread was baked and produced using a general-purpose convection oven.
In Examples 1, 4 and 7, the firing temperature was 150 ° C., in Examples 2, 5 and 8, the firing temperature was 180 ° C., and in Examples 3, 6 and In Example 9, the firing temperature was 200 ° C., and the firing time was 30 minutes in each case.

The baking and baking work of bread was repeated for the baking containers of Examples 1 to 9 to evaluate the number of reusable times. The results are shown in Table 2 below. If the opening displacement of the baking container is 5 mm or less, it can be reused for baking and baking of bread, and if the opening displacement exceeds 5 mm, it can be reused. The number of times of use up to that point was totaled as impossible.
As can be seen from Table 2, it was confirmed that the baking containers of Examples 1 to 9 could be used multiple times.

Next, as Example 10, an aluminum alloy piece obtained by continuous casting with the alloy composition shown in Table 1 was subjected to sheet annealing, and then subjected to intermediate annealing at a temperature of 300 ° C. for 5 hours at a thickness of 0.5 mm to obtain a thickness of 75 μm. An aluminum alloy foil was obtained.
Further, as Example 11, an aluminum alloy piece obtained by continuous casting with the alloy composition shown in Table 1 was subjected to intermediate annealing at a temperature of 400 ° C. for 5 hours at a thickness of 1.2 mm after plate rolling, and aluminum having a thickness of 75 μm was formed. An alloy foil was obtained.
Similarly, as Comparative Example 1, an aluminum alloy piece obtained by continuous casting with the alloy composition shown in Table 1 was subjected to intermediate annealing at a temperature of 170 ° C. for 5 hours at a thickness of 1.2 mm after plate rolling to obtain a thickness of 75 μm. An aluminum alloy foil was obtained.
Further, as Comparative Example 2, an aluminum alloy piece obtained by continuous casting with the alloy composition shown in Table 1 was subjected to intermediate annealing at a temperature of 500 ° C. for 5 hours at a thickness of 0.5 mm after plate rolling, and aluminum having a thickness of 75 μm was formed. An alloy foil was obtained.

The tensile strength and the elongation of these Examples 10 and 11 and Comparative Examples 1 and 2 were evaluated. The results are shown in Table 3 below.
In the evaluation, even if the aluminum alloy foil was softened at 150 ° C. for up to 240 minutes, the tensile strength was kept at 120 N / mm ² or more and the elongation was 3.0% or more, and the result was ◯. Others were marked with x.
Similarly, even if the softening treatment was performed at 180 ° C. for up to 240 minutes, the tensile strength was maintained at 100 N / mm ² or more and the elongation was 3.0% or more. did.
Further, even if the softening treatment was performed at 200 ° C. for up to 240 minutes, the tensile strength was maintained at 90 N / mm ² or more and the elongation was 3.0% or more, which was marked as ◯, and the others were marked as x. .
This is because elongation of 2.0% or more is usually required for deep-drawing the aluminum foil into a container.

For Examples 10 and 11 and Comparative Examples 1 and 2, heating was performed using a commonly used heater, and changes in tensile strength (N / mm ² ) and elongation (%) depending on heating time were measured. . The results are shown in FIGS.
1 and 2 show tensile strength and elongation at a heating temperature of 150 ° C., FIGS. 3 and 4 show tensile strength and elongation at a heating temperature of 180 ° C., and FIGS. The tensile strength and elongation at 200 ° C are shown.
In each figure, the plot of ■ indicates Example 10, the plot of ▲ indicates Example 11, the plot of ◆ indicates Comparative Example 1, and the plot of × indicates Comparative Example 2.

As can be seen from the figures, in Examples 10 and 11, the tensile strength was maintained at 120 N / mm ² or more even after heating at 150 ° C. for 240 minutes (at a heating time of 240 minutes, in Example 10, about 10 minutes). 170 N / mm ² , in Example 11, about 130 N / mm ² ) and has an elongation of 2.0% or more (at a heating time of 240 minutes, in Example 10, about 3.5%, 11 is about 6.5%).
Even when heated at 180 ° C. for 240 minutes, the tensile strength was maintained at 100 N / mm ² or more (at a heating time of 240 minutes, 140 N / mm ^{2 in} Example 10 and about 110 N / mm in Example 11). ² ) And, it has an elongation of 3.0% or more (at a heating time of 240 minutes, about 7.5% in Example 10 and about 8.0% in Example 11).
Even when heated at 200 ° C. for 240 minutes, the tensile strength was maintained at 90 N / mm ² or more (at a heating time of 240 minutes, in Example 10, about 130 N / mm ² and in Example 11, about 110 N / mm ²⁾ . mm ² ), and an elongation of 3.0% or more (at a heating time of 240 minutes, about 6.5% in Example 10 and more than 8% in Example 11).

On the other hand, in Comparative Example 1, as shown in FIGS. 2, 4, and 6, the elongation when heated to 150 ° C. for 240 minutes is less than 2.0%, and the elongation at 180 ° C. for 240 minutes. The elongation when heated was less than 3.0% and the elongation when heated at 200 ° C. for 240 minutes was less than 3.0%, and the desired elongation was not obtained.
Further, in Comparative Example 2, as shown in FIGS. 1, 3 and 5, the tensile strength when heated to 150 ° C. for 240 minutes exceeded 120 N / mm ^2, and the sample was heated to 180 ° C. for 240 minutes. The tensile strength in this case is higher than 100 N / mm ^2, but the tensile strength when heated at 200 ° C. for up to 240 minutes is lower than 75 N / mm ² and 90 N / mm ² , so that the aluminum alloy foil of the present invention The desired tensile strength was not obtained.

  The embodiments and examples disclosed this time are to be considered as illustrative in all points and not restrictive. The scope of the present invention is shown by the claims, and is intended to include meanings equivalent to the claims and all modifications and variations within the scope.

Claims (4)

The tensile strength is maintained at 120 N / mm ² or more and the elongation is 2.0% or more even after the softening treatment at 150 ° C. for 240 minutes.
Even after softening treatment at 180 ° C for 240 minutes, the tensile strength is kept at 100 N / mm ² or more and the elongation is 3.0% or more.
Even after softening treatment at 200 ° C. for 240 minutes, the tensile strength is maintained at 90 N / mm ² or more, and the elongation is 3.0% or more,
0.3 mass% or more and 3.0 mass% or less of iron,
0.8 mass% or more and 1.5 mass% or less of silicon,
0.0001% by mass or more and 0.011% by mass or less of copper;
0.0001 mass% or more and 0.6 mass% or less of manganese,
0.0001 mass% or more and 0.011 mass% or less of magnesium;
0.001% by mass or more and 0.011% by mass or less of zinc;
0.005 mass% or more and 0.5 mass% or less of titanium;
Including 0.0001 mass% or more and 0.3 mass% or less zirconium,
An aluminum alloy foil whose balance consists of aluminum and inevitable impurities . The aluminum alloy foil according to claim 1, having a thickness of 5 to 100 μm. An aluminum container comprising the aluminum alloy foil according to claim 1 . 0.3 mass% or more and 3.0 mass% or less iron, 0.8 mass% or more and 1.5 mass% or less silicon, 0.0001 mass% or more and 0.011 mass% or less copper, and 0001 mass% or more and 0.6 mass% or less manganese, 0.0001 mass% or more and 0.011 mass% or less magnesium, 0.001 mass% or more and 0.011 mass% or less zinc, and 0.005 mass% % Or more and 0.5 mass% or less of titanium and 0.0001 mass% or more and 0.3 mass% or less of zirconium, and a step of preparing an aluminum alloy in which the balance is aluminum and inevitable impurities,
A step of forming the aluminum alloy into aluminum alloy pieces by continuous casting,
Plate rolling the aluminum alloy piece into an aluminum alloy plate having a thickness of 0.5 mm to 1.2 mm;
A step of performing intermediate annealing at 300 to 400 ° C. in an intermediate step of the sheet rolling,
Foil-rolling the aluminum alloy sheet to an aluminum alloy foil having a thickness of 5 to 100 μm.
The tensile strength is maintained at 120 N / mm ² or more and the elongation is 2.0% or more even after the softening treatment at 150 ° C. for 240 minutes .
Even after softening treatment at 180 ° C for 240 minutes, the tensile strength is kept at 100 N / mm ² or more and the elongation is 3.0% or more.
A method for producing an aluminum alloy foil, which has a tensile strength of 90 N / mm ² or more and an elongation of 3.0% or more even after being softened at 200 ° C. for 240 minutes .

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