JP3529268B2 - Aluminum foil ground and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aluminum foil suitable as a thin foil for packaging foods and the like, film capacitors, labels, cigarettes and the like, and a method for producing the same, and particularly to a pole having a thickness of 15 μm or less. The present invention relates to an aluminum foil material used for bookkeeping aluminum foil and having improved pinhole characteristics, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, pure aluminum such as JIS1N30 or aluminum alloy such as JIS8079 or 8021 is used as a material for aluminum or aluminum alloy foil for thin foil.

In the following, pure aluminum and aluminum alloys are collectively referred to as aluminum. Aluminum foil land generally aluminum ingot to homogenization, hot rolling, cold rolling及beauty sintered blunt alms these compositions, and if necessary, prepared by subsequently subjected to cold rolling Has been done.

Then, the aluminum foil obtained is subjected to foil rolling and final annealing to obtain an aluminum foil. By the way, although 5.5 to 7 μm aluminum foil has been put into practical use, the demand for thin foil is mostly 6 to 7 μm, and aluminum foil of the same thickness is JIS 1N30 pure aluminum in view of compatibility in foil rolling. There is a strong desire to use.

Generally, the problems associated with the reduction of the foil thickness are that the number of pinholes increases significantly, the barrier properties against the light, gas, liquid, etc., which the foil should have, are reduced, and the pinholes cause the problem. It is known that foil breakage occurs.

It is known that the finish foil rolling of a thin foil is usually carried out by polymerization rolling, and pinholes are formed at the maximum waviness of the matte surface by connecting with the bright surface oil pits. It is also known that pinholes are mainly governed by the matte surface roughness, as compared with surface defects such as oil pits. Furthermore, it is considered that the oil pits are mainly controlled by rolling conditions (reduction, back tension), and the matte surface is formed by free deformation of crystal grains, and it is known that the factor controlled by the foil is large. (Japanese Patent Publication No. 3-60562, Light Metal Society 70th Proceedings)
33, 34, 35).

Therefore, conventionally, in order to reduce the matte surface roughness, the Fe solid solubility is reduced by increasing the Fe content and changing the manufacturing conditions after soaking, and the work hardening is performed by refining the crystal grains. A foil that can be suppressed is disclosed (Japanese Patent Laid-Open No. 63-26322, etc.). Further, a technique has been proposed in which the addition of Ni, Mn, and Cr makes the crystal grains finer and suppresses work hardening (Japanese Patent Laid-Open No. 63-228228).
JP, JP-A-63-282244, and JP-A-8
-333644).

[0008]

However, Fe,
In the aluminum foil with Ni, Mn or Cr added,
There is no merit of compatibility as described above, and JIS1
In the case of a composition equivalent to N30 pure aluminum, if the Fe content does not increase, in the foil rolling to obtain an aluminum foil having a foil thickness of 6 to 7 μm, even if precipitation is promoted by changing the manufacturing conditions after soaking, A large effect of suppressing work hardening cannot be obtained. Further, even if the precipitation is promoted by changing the manufacturing process, the crystal grains may become large on the contrary, which causes problems that pinholes frequently occur and foil breakages frequently occur.

The present invention has been made in view of the above problems, and even with a pure aluminum composition equivalent to JIS 1N30, an aluminum foil material that can be thinned without impairing the foil rollability and pinhole characteristics. And its manufacturing method.

[0010]

The aluminum foil according to the present invention contains Fe: 0.3 to 1.0 % by weight, the impurity Si is regulated to less than 0.15% by weight, and the balance is Al.
And an aluminum alloy composition consisting of unavoidable impurities, and the total number of intermetallic compounds of 0.1 to 0.3 μm is 4 ×.
It is characterized in that it is set to 10 ^{8 to} 10 × 10 ⁸ pieces / mm ³ .

In this aluminum foil, the aluminum alloy may be Cu: 0.02% by weight, if necessary.
Hereinafter, Ti: 0.03 wt% or less can be contained.

Further, the method for producing an aluminum foil according to the present invention comprises semi-continuously casting a molten metal having an aluminum alloy composition having the above composition at a cooling rate during solidification of 0.3 to 3.0 ° C./sec. After chamfering, homogenizing treatment is performed in the temperature range of 400 to 620 ℃, 320 ℃ to 450 ℃
Rolling rate of 37 to 60% per pass in the full temperature range
Hot rough rolling at a finishing temperature of 200-260 ℃
After hot finish rolling so that it falls within the range, cold rolling with a rolling ratio of 50% or more is performed, and then at 300 to 450 ° C. for 2 hours.
The total number of intermetallic compounds of 0.1 to 0.3 μm is 4 × 10 ^{8 to} 10 × 10 ⁸ pieces / m by annealing for more than 10 minutes.
It is characterized in that a foil material having m ³ is obtained.

In the method for producing the aluminum foil,
As step after the previous SL sintered blunt, may be provided cold rolling step.

The inventors of the present invention have conducted various experiments and researches on aluminum foil / foil to solve the problems. As a result, in order to reduce pinholes, the matte surface roughness should be lowered, that is, during finishing foil rolling. It was found that it is effective to miniaturize the deformed block. The inventors of the present application have also found that the matt surface is formed not only by the crystal grain size but also by free deformation of the dislocation cell size. Further, it is known that suppressing work hardening is effective for reducing pinholes, but the inventors of the present invention have achieved this phenomenon by forming sub-grains by dislocation organization. Investigated.

Therefore, as a result of earnest research to develop an aluminum foil for exhibiting the above characteristics,
It is effective to optimize the total number of intermetallic compounds of 0.1 to 0.3 μm, and in the case of JIS1N30 pure aluminum composition, the optimization of the total number of intermetallic compounds of this size has been performed conventionally. It has been found that the adjustment is difficult only by changing the manufacturing conditions after the heat, and that the purpose can be achieved by controlling the combination of the appropriate casting conditions and the foil manufacturing conditions after the soaking. The present invention has been made based on these findings.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. First, the reasons for adding components and the reasons for limiting the composition of the aluminum foil according to the present invention will be described.

(1) Fe: 0. 3乃 optimum 1.0 wt% Fe is small solid solubility limit of the aluminum is an element in aluminum was bonded to other element to produce a Al-Fe-based intermetallic compound, the compound recrystallization Since it acts as a nucleus, the addition of Fe is effective in refining the crystal grains. Intermetallic the number Fe content of crystallized during casting is less than 0.3% by weight is insufficient, difficult to obtain the effect of refining crystal grains. On the other hand, when the Fe content exceeds 1.0% by weight, a large number of Al-Fe-based crystallized substances are formed, so that the grain refining effect is large, but the deformation resistance during foil rolling increases. Therefore, the rolling property is extremely reduced. Therefore, the Fe content is 0. 3 and 乃 optimum 1.0 wt%.

(2) Si: less than 0.15 wt% Si is one of the inevitable impurities in the metal. Si is
It is easy to generate coarse Al-Fe-Si intermetallic compounds,
The smaller the number, the better because it causes an increase in pinholes. Therefore, it is desirable that the Si content be less than 0.15% by weight.

(3) Total number of 0.1 to 0.3 μm intermetallic compounds : 4 × 10 ^{8 to} 10 × 10 ⁸ pieces / mm ³ 0.1 to 0.3 μm intermetallic compounds are mainly precipitates. Yes, it is produced by homogenization treatment, hot rolling and intermediate annealing.
The distribution of these intermetallic compounds is due to the accumulation of dislocations during foil rolling.
In order to affect the ordering, it affects the deformed block size of dislocation cell order in the subsequent polymerization rolling. The total number of intermetallic compounds of the same size is 10 × 10 ⁸ / mm ³
When the value exceeds the above, a so-called pinning phenomenon occurs in which the movement of dislocations is hindered by the intermetallic compound in the pass before the polymerizing rolling, which causes excessive accumulation of dislocations, and in the subsequent polymerizing rolling, a plurality of dislocation cells are formed. To become a transformation block,
The matte surface becomes rough and pinholes frequently occur. On the other hand, the total number of intermetallic compounds of the above size is 4 × 10 ⁸ / mm ³
If it is less than, it becomes easy to arrange the transitions in the pass before polymerization rolling,
Although it is a deformed block with a single cell, since a coarse cell is easily formed, the matte surface becomes rough and pinholes frequently occur. Therefore, the total number of intermetallic compounds of 0.1 to 0.3 μm is set to 4 × 10 ^{8 to} 10 × 10 ⁸ pieces / mm ³ .

(4) Cu: 0.02 wt% or less Cu is an element that forms a solid solution in aluminum, is effective in improving the strength of O material by solid solution hardening, and may be added if necessary. When the Cu content is less than 0.005% by weight,
Solid solution hardening is insufficient, and it is difficult to obtain the effect of improving the strength of O material. On the other hand, when the Cu content exceeds 0.02% by weight, the degree of solution hardening is too large and the deformation resistance during foil rolling increases, so that the rolling property is extremely reduced. Therefore,
Cu may be added as necessary as long as it is 0.02% by weight or less.

(5) Ti: 0.03 wt% or less Ti is added as an Al-Ti or Al-Ti-B mother alloy and is used for refining the ingot structure. When the striped pattern becomes a problem after foil rolling, it may be added in the range of 0.03% by weight or less. However, if Fe-like crystals are formed without adding Ti, the intermetallic compound crystallized in the ingot becomes finer. Therefore, it is preferable that the amount of Ti is small as long as the streak pattern is not hindered. Therefore, Ti may be added as needed as long as it is 0.03% by weight or less.

(6) Inevitable Impurities In addition to the above inevitable impurities contained in aluminum, Mn, Mg, Zn, Cr, V, Zr, Bi and S are included.
Although n, In, Pb and the like can be mentioned, if they are contained within the range of JIS 1100 and 1N30, they do not impair the object of the present invention.

Next, the reasons for limiting the processing conditions in the method for manufacturing an aluminum foil according to the present invention will be described.

(1) Cooling rate during solidification: 0.3 to 3.
0 ° C./sec As described above, in order to exhibit excellent pinball characteristics as a foil, it is necessary to optimize the total number of intermetallic compounds of 0.1 to 0.3 μm in the foil. This optimization of the total number of intermetallic compounds is difficult to adjust simply by changing the manufacturing conditions after soaking, which has been conventionally performed, and is controlled by combining the optimization of casting conditions and the manufacturing conditions of the foil after soaking. By that, the purpose is achieved.

That is, optimizing the cooling rate during solidification optimizes the total number of intermetallic compounds of the same size, which contributes to the reduction of pinholes. In the slab that was ingoted at a cooling rate during solidification exceeding 3.0 ° C / sec, the supersaturated solid solution Fe was discharged as fine precipitates by the subsequent homogenization treatment, hot rolling treatment, and intermediate annealing. The number of precipitates having a size of 0.3 μm or less is extremely increased, and pinning is performed, so that the matte surface becomes rough, resulting in frequent occurrence of pinholes. on the other hand,
If the cooling rate during solidification is less than 0.3 ° C./sec, floating crystals are generated in the glass screen, and it is difficult to make an ingot as a rolling slab. Therefore, the cooling rate during solidification is 0.3 to 3.0 ° C./second, preferably 0.3 to 2.
4 ° C / sec.

(2) Homogenization treatment: 400 to 620 ° C. The slab having the above composition and agglomeration conditions is chamfered and then homogenized. This homogenization treatment is performed for the purpose of adjusting solid solution and precipitation, and is an important treatment for optimizing the total number of intermetallic compounds of 0.1 to 0.3 μm, and contributes to the reduction of pinholes. Homogenization temperature is less than 400 ° C, or 6
If it exceeds 20 ° C., the number of precipitates due to the precipitation of solid solution elements becomes insufficient, and the total number of intermetallic compounds becomes insufficient, resulting in frequent occurrence of pinholes. Note. Homogenization treatment temperature is 400
Even if the temperature is lower than 0 ° C, solid solution elements are sufficiently precipitated when annealing is performed for a long time, but this is not preferable because the production efficiency deteriorates. Therefore, the homogenization treatment temperature is 400 to 620.
℃. The homogenizing treatment time is not particularly specified, but it is preferably performed for 2 hours or more.

(3) Cold rolling reduction rate: 50% or more , annealing : 300 to 450 ° C. After the above homogenization treatment, hot rolling is performed, and then cold rolling is performed. to burn blunt to. Although baked blunt This is what is done for the purpose of precipitation and recrystallization of solid solution elements, total intermetallic compound number of 0.1 to 0.3μm described above is influenced by the tempering blunt temperature and reduction ratio. Rolling rate is less than 50%, or baked blunt temperature 30
When the temperature is lower than 0 ° C. or higher than 450 ° C., the number of precipitates due to the precipitation of the solid solution element becomes insufficient and the total number of intermetallic compounds becomes insufficient, resulting in frequent occurrence of pinholes. Note.
Even if the annealing temperature is lower than 300 ° C., when solid-state annealing is performed for a long time, the solid solution element is sufficiently precipitated, but the production efficiency is deteriorated, which is not preferable. For this reason, baked blunt temperature is 30
The temperature is 0 to 450 ° C. Although not particularly specified burn blunt time this is preferably carried out over 2 hours.

(4) Hot rough rolling condition : less than 450 ° C. 32
0 ° C or higher, rolling rate per pass 37 to 60% O Improvement of O material strength and reduction of matte surface roughness can also be achieved by refining crystal grains, and reliable recrystallization should be repeated in hot rough rolling. are the effective grain refinement, if necessary, may be subjected to the following rough hot rolling. In order to optimize the recrystallized grain size, it is necessary to optimize the rolling ratio per pass and the temperature range in the hot rough rolling.

The rolling rate per pass is less than 37%,
Alternatively, if the temperature is lower than 320 ° C., recrystallization does not occur and the degree of refinement of crystal grains is insufficient. On the other hand, if the rolling rate per pass exceeds 60% or the temperature exceeds 450 ° C., grain growth occurs and the crystal grains become coarse. Therefore, when grain refinement is performed by hot rough rolling, if necessary, the rolling rate is less than 450 ° C. and 320 ° C. or more, and the rolling rate per pass is 37 to 60%.

(5) End temperature of hot finish rolling : 200 to 260 ° C. Similarly to the above, the following hot finish rolling for the purpose of grain refinement may be carried out as necessary. Hot coil refining changes the final hot rolling temperature was enhanced accumulation of R orientation without increasing the thickness of the hot coil by a hot finish rolling temperature to a low temperature, re桔晶in baked blunt Grain refinement can be achieved. When the rolling end temperature finish hot exceeds 260 ° C., the accumulation of R orientation is insufficient, not too fine crystal grains are obtained in the baked blunt. On the other hand, when the hot finish rolling finish temperature is less than 200 ° C., the coil shape required for the foil cannot be obtained, and the rolling property in foil rolling is poor. Therefore, if necessary, in the case of refining crystal grains, and it terminates the hot finish rolling at 200 to 260 ° C..

[0031]

EXAMPLES The characteristics of the aluminum foil materials according to the examples of the present invention will be specifically described below in comparison with comparative examples that depart from the claims of the present invention. Example 1 A molten aluminum having the composition shown in Table 1 below was semi-continuously cast (DC) at the cooling rate during solidification shown in the same table, and the obtained slab was chamfered, and then at a temperature of 540 ° C. for 8 hours. Homogenization treatment is started, and hot rolling is started immediately after that, and the thickness is 5 mm.
A thick aluminum plate was obtained. After that, cold rolling was performed at a rolling rate of 86%, and the obtained sheet was subjected to intermediate annealing at a temperature of 420 ° C. for 6 hours. Further cold-rolled to a thickness of 0.3 mm
Made of aluminum foil .

The aluminum foil obtained is foil-rolled.
An aluminum foil having a thickness of 6 μm was produced, and rollability during foil rolling was evaluated. As a result, when rolling
The same rolling condition as ○ (good)
If it is difficult to reduce the wall thickness, or if the strength is insufficient, the rolling speed
It is difficult to control the flatness such as plate thickness distribution, etc.
When there was a strong tendency for troubles to occur, x (bad)
And In addition , those in which the slab could not be removed for rolling due to the generation of floating crystals during the ingot making were also marked as x (defective).

Next, according to a conventional method, the final annealed thickness
There width aluminum foil 6μm is 15 mm, and the short Satu shape of the effective length of 100 mm, which will measure the tensile strength by Instron type tensile tester, which was used as O material strength. The O material strength is inferior to less than 55 MPa, 55 to 7
It shows that it is particularly excellent when it exceeds 5 MPa.

With respect to the aluminum foil having a thickness of 6 μm, the number of pinholes per 1 m ² (having a diameter of 5 μm or more) was measured by a pinhole detector. Pinholes of 100 holes / m ² or less are excellent.

The cooling rate during solidification, the total number of intermetallic compounds of 0.1 to 0.3 μm, and the crystal grain size in the table were measured as follows.

The cooling rate at the time of solidification was 10 from the skin of the central part of the wide surface, after taking a steady part on the bottom side of the ingot after casting.
It was calculated by collecting a small piece from the position of 0 mm, and after electrolytic polishing, measuring the DAS (dendritic arm spacing) by the intersecting line method and the secondary technique. Correction of measured values by the crossing method and the secondary technique was performed by the following empirical formula (Formula 1).

[0037]

## EQU00001 ## dr = 1.49ds, where dr is the DAS by the intersecting method and ds is the DAS by the quadratic technique. And the cooling rate C at the time of solidification was calculated by the following Numerical formula 2.

[0038]

## EQU00002 ## When the amount of Fe.ltoreq.0.65% by weight: ds = 33.
4 · C ^−0.33 Fe content> 0.65% by weight: ds = 77 · C ^−0.42

These equations 1 and 2 are given in the Report No. 20 "Dentrite arm spacing of aluminum and measuring method of cooling rate".

The total number of intermetallic compounds of 0.1 to 0.3 μm was measured using a transmission electron microscope and an image processor. That is, a 7.5 mm square piece was taken from the foil and
After polishing to a thickness of 1 mm, it is punched into a diameter of 3 mm. 35 this
Dislocation removal treatment was performed at 0 ° C. for 5 minutes, and then an observation sample having a thickness of about 5 μm was prepared by jet polishing. The precipitates were observed with a transmission electron microscope at a magnification of × 10,000, and photographs of the number of fields of view with which the total area was 3512 μm ² were taken. Further, by counting these photographs by image processing, the total number of intermetallic compounds of 0.1 to 0.3 μm was calculated.

The crystal grain size was calculated by a cross line method from a photograph obtained by picking a small piece from a medium blunt plate, subjecting it to electrolytic polishing, and polarizing it with an optical microscope and taking a picture at a magnification of × 100.

The aluminum foils of Examples and Comparative Examples were evaluated on the basis of the above-mentioned rolling evaluation criteria, pinhole characteristics and O material strength measurement conditions. The evaluation results and measurement results are shown in Table 1 below. .

[0043]

[Table 1]

As shown in Table 1, No. 1 of the first embodiment.
For 1 to 6, good rollability was obtained. Further, regarding the pinhole and O material strength, No. 1 of Example 1 was used. 1 to 6 is a preferable value, and a good aluminum foil could be obtained throughout.

On the other hand, Comparative Example No. In No. 1, although the pinhole and O material strength were good, the rolling property deteriorated due to the addition of excess Fe. Comparative Example No. In No. 2, the rolling property was good, but the crystal grains could not be made small due to the lack of Fe content, and the pinhole and O material strength were inferior to those of the examples.
Comparative Example No. Although Nos. 3 and 5 were good in rolling property and O material strength, Comparative Example No. A large amount of pinholes was generated in No. 3 due to excessive addition of Si and in Comparative Example 5 due to excessive addition of Ti. Comparative Example No. In No. 4, although the O material strength was good, the rollability and pinhole characteristics were inferior to those of the examples due to excessive addition of Cu. Comparative Example No. 7, 9, 11,
Sample No. 13 had good rollability and O material strength, but the cooling rate during casting and solidification was too fast, and the total number of intermetallic compounds of 0.1 to 0.3 μm was excessively large, resulting in a rough matte surface. And a lot of pinholes were generated. Comparative Example No.
In Nos. 6, 8, 10, and 12, the cooling slab could not be manufactured because the cooling rate at the time of solidification by casting was too slow and floating crystals were generated in the glass screen.

(Example 2) No. 1 of Example 1 in Table 1 above.
With respect to the ingots having the same composition and cooling rate at the time of solidification as those of 1, 4, and 6, after chamfering, homogenization treatment shown in Table 2 below was performed, and immediately after that, hot rolling was started and the thickness was 5 mm. An aluminum plate was obtained. Then, cold rolling and intermediate annealing were performed at the rolling rate and the annealing temperature shown in Table 2. Furthermore, cold rolling,
An aluminum foil having a thickness of 0.3 mm was produced. The aluminum foil obtained was rolled and finally annealed to produce an aluminum foil having a thickness of 6 μm.

Table 2 below shows the results of evaluation or measurement based on the same rollability evaluation criteria as in Example 1 and the measurement conditions of pinhole characteristics and O material strength.

[0048]

[Table 2]

As shown in Table 2 above, No.
For 7 to 12, good rolling property was obtained. In addition, regarding the number of pinholes and the strength of the O material, No. 2 of Example 2 was used. It was a preferable value for 7 to 12, and a good foil could be obtained over the whole.

On the other hand, Comparative Example No. Nos. 14 to 25 were good in terms of rollability, but in any case, the homogenization temperature or the intermediate annealing temperature was too high or too low, or the rolling ratio was insufficient, so that the interparticle distance was widened. As a result, the matte surface became rough and many pinholes were generated.

(Example 3) No. 1 of Example 1 in Table 1 above. For the ingots having the same composition and cooling rate at the time of solidification as those of 1, 4, and 6, homogenization treatment was performed at a temperature of 600 ° C. for 8 hours after chamfering, and immediately after that, hot rolling was started, and Table 3 below was used. The hot rough rolling and the hot finish rolling shown in 1) were performed to obtain an aluminum plate having a thickness of 5 mm. After that, cold rolling was performed at a rolling ratio of 87%, and the obtained plate was 400 ° C.
Intermediate annealing was performed at the temperature of 6 hours. Further, it was cold-rolled to produce an aluminum foil having a thickness of 0.3 mm.
The aluminum foil obtained was rolled and finally annealed to produce an aluminum foil having a thickness of 6 μm.

Table 3 below shows the results of evaluation or measurement based on the same rolling property evaluation criteria as in Example 1 above and the measurement conditions of pinhole characteristics and O material strength.

[0053]

[Table 3]

As shown in Table 3 above, N of Example 3
o. Good rolling properties were obtained for Nos. 13 to 15. In addition, regarding the number of pinholes and the strength of O material, Example No.
13 to 15 are preferable values, and particularly regarding the O material strength, Example No. 1 shown in Examples 1 and 2. Compared with Nos. 1 to 12, even if the chemical composition was the same, a high level of O material strength was obtained, and an excellent foil could be obtained over the whole.

On the other hand, Comparative Example No. Regarding No. 26, the O material strength was good, but the finish temperature of hot rolling finish rolling was too low, a good coil shape could not be obtained, and foil rollability and pinhole characteristics were poor. Comparative Example No. Nos. 27, 29, and 30 are good in foil rollability, the number of pinholes, and the O material strength. The characteristics were equivalent to those of Nos. 1 to 12 and were not particularly excellent. Comparative example
No. Nos. 28 and 31 had good rolling property and pinhole number, but because the temperature range of hot rolling rough rolling was high or the rolling ratio was high, the crystal grains became larger and the O material strength was particularly excellent. No. 1 and No. 2 shown in Examples 1 and 2.
The characteristics were equivalent to those of Nos. 1 to 12 and were not particularly excellent.

[0056]

As described above in detail, according to the present invention, 0.1 to 0.3 can be controlled by controlling the cooling rate during the solidification of the casting, the homogenization treatment condition, the cold rolling rate and the intermediate annealing treatment condition.
By optimizing the total number of intermetallic compounds of μm, it is possible to obtain an aluminum foil having excellent foil rollability and a small number of pinholes after foil rolling.

[0057] Furthermore, by combining the rolling reduction and optimizing the end temperature of the hot finish rolling per temperature range and one pass in the hot rough rolling, it is possible to miniaturize the crystal grains, foil rolling resistance It is possible to obtain an aluminum foil material which is excellent in the number of pinholes generated after foil rolling and has excellent O material strength.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-333644 (JP, A) JP-A-6-25781 (JP, A) JP-A-6-293931 (JP, A) JP-A-4- 337043 (JP, A) JP 59-64754 (JP, A) JP 61-257459 (JP, A) Miki Isao, Iron index during solidification of Al-Fe alloy, light metal, Japan, light metal , 1975, January, Vol. 25, No. 1, p. 1-9 (58) Fields investigated (Int.Cl. ⁷ , DB name) C22C 21/00-21/18 C22F 1/04-1/057

Claims (5)

(57) [Claims] 1. Fe: 0.3 to 1.0 % by weight,
Impurity Si is regulated to less than 0.15% by weight, the balance has an aluminum alloy composition consisting of Al and unavoidable impurities, and the total number of intermetallic compounds of 0.1 to 0.3 μm is 4
An aluminum foil having a density of x10 ^{8 to} 10 x 10 ⁸ pieces / mm ³ . 2. The aluminum alloy is Cu: 0.0
The aluminum foil according to claim 1, which contains 2% by weight or less. 3. The aluminum alloy comprises Ti: 0.0
The aluminum foil material according to claim 1 or 2, which contains 3% by weight or less. 4. A molten metal having the aluminum alloy composition according to claim 1 is semi-continuously cast at a cooling rate during solidification of 0.3 to 3.0 ° C./sec and chamfered. After that, homogenization treatment is performed in the temperature range of 400 to 620 ° C, and 1 hour in the temperature range of 320 ° C or higher and lower than 450 ° C.
Hot rough rolling at a rolling rate of 37 to 60%
Hot to keep the temperature in the range of 200-260 ℃
After finish rolling, cold rolling with a rolling ratio of 50% or more is performed.
By annealing over 2 hours then 300 to 450 ° C., the total number of intermetallic compound of 0.1 to 0.3 [mu] m 4
× 10 ⁸ to 10 × l0 ⁸ pieces / mm ³ in which the aluminum foil land production method characterized by obtaining a foil land. As subsequent steps wherein before Symbol sintered blunt, aluminum foil land method according to claim 4, characterized in that cold rolling.