JP2001073104A - Manufacture of aluminum alloy soft sheet for deep drawing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing an Al alloy soft sheet excellent in strength and formability, reduced in earing rate, and improved in adhesion to resin film as well as in surface quality. SOLUTION: An ingot, having a composition consisting of, by weight, 0.3-0.9% Fe, 0.7-1.5% Mn, 0.1-0.7% Mg, further one or more kinds among 0.01-0.3% Si, 0.01-0.5% Cu, 0.01-0.5% Zr, 0.01-0.5% V, 0.005-0.2% Ti, and 0.0001-0.05% B, and the balance Al, is subjected to homogenizing treatment at >=530 deg.C and then to hot rolling at 380-580 deg.C hot rolling starting temperature and at 200-300 deg.C hot rolling finishing temperature. The resultant plate is subjected to primary cold rolling at >=50% rolling rate, to process annealing at 250-500 deg.C for >=0.5 hr, and then to secondary cold rolling at >=50% rolling rate. Further, as final annealing, the resultant sheet is heated up to 250-500 deg.C and held for >=0.5 hr to undergo batch annealing or is subjected to heating up to 350-600 deg.C with or without holding for <=10 min to undergo continuous annealing.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an aluminum alloy soft plate for use in forming by deep drawing, such as a retort container, a container, a packaging container, and the like. An aluminum alloy soft plate suitable for use in combination with a film,
The present invention relates to a method for producing an aluminum alloy soft plate for deep drawing, which has high strength, is excellent in drawing workability, has a stable low ear ratio, and is also excellent in surface quality and corrosion resistance.

[0002]

2. Description of the Related Art In general, a foil-like aluminum plate formed by laminating (laminating) a synthetic resin film such as polyethylene is used for a retort container, a container, a cap, and the like by deep drawing. Conventionally, as an aluminum alloy for such an application, JIS 105
Al-Fe such as 0 alloy, 1100 alloy, 1200 alloy
-Si-based alloy completely annealed soft material (O material) or H1
n, H2n temper material or the like is used.

[0003] By the way, aluminum alloy sheets for these uses have to have uniform mechanical properties, low ear ratio in deep drawing, high strength, excellent formability, and surface quality. It is required that the resin-laminated aluminum foil has good adhesion to a resin film so as to exhibit good corrosion resistance.

On the other hand, recently, mainly from the viewpoint of cost reduction, it has been required to further reduce the thickness of the aluminum alloy plate used as the above-described resin-laminated aluminum foil as compared with the conventional one. It is required to have a higher strength than before, and as a retort container product, it is required that the handleability is good, such as dents do not occur during transportation etc. High strength is required.

[0005]

The JIS as described above
Al- such as 1050 alloy, 1100 alloy, 1200 alloy
Although the O material of the Fe—Si alloy has good formability, it has low strength and cannot meet the above-mentioned requirements sufficiently. On the other hand, H1n temper material and H2n
The temper material can meet the above-mentioned requirements in terms of strength, but has a fundamental problem that the moldability is inferior. Therefore, it is conceivable to use an Al-Mn-Mg-based alloy such as 3004 alloy.
-Mn-Mg-based alloys can secure strength and formability to some extent, but are inferior in adhesion to a resin film, and thus may have reduced corrosion resistance as a resin-laminated aluminum foil. That is the fact.

The present invention has been made in view of the above circumstances. As an aluminum alloy plate used for deep drawing such as resin-laminated aluminum foil such as a retort container, the strength and drawability of a soft material can be improved. It is an object of the present invention to provide a method for obtaining a material which is excellent, has good adhesion to a resin film, has a low ear ratio, and has excellent surface quality.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive experiments and studies in order to solve the above-mentioned problems, and as a result, it has been found that the component system of the alloy is basically an Al-Fe-Mn-Mg system. Appropriately regulate the content of elements,
In particular, homogenization treatment, hot rolling, primary cold rolling, intermediate annealing,
The present inventors have found that the aforementioned problems can be solved by appropriately controlling the conditions of the secondary cold rolling and the final annealing, and have accomplished the present invention.

[0008] Specifically, the method for producing an aluminum alloy soft plate for deep drawing according to the first aspect of the present invention is characterized in that:
0.9%, Mn 0.7-1.5%, Mg 0.1-0.7
% Of Si, 0.01 to 0.5% of Si, and 0.1% of Cu.
01-0.5%, Cr 0.01-0.5%, Zr0.0
1-0.5%, V0.01-0.5%, Ti0.005
Alloy containing at least one member selected from the group consisting of Al and unavoidable impurities.
After performing the homogenization treatment at a temperature of 30 ° C. or more, hot rolling is performed with the hot rolling start temperature in the range of 380 to 580 ° C. and the hot rolling end temperature in the range of 200 to 300 ° C.,
Further, after performing primary cold rolling at a rolling rate of 50% or more, intermediate annealing is performed at a temperature in the range of 250 to 500 ° C. for 0.5 hour or more, and then secondary rolling is performed at a rolling rate of 50% or more. Cold rolling is performed, and as final annealing, 10
Batch annealing is performed by heating to a temperature in the range of 250 to 500 ° C. at a heating rate of 0 ° C./hr or less and holding for 0.5 hour or more, whereby the tensile strength is 120 MPa or more and the elongation is 1
5% or more, deep drawing ear ratio 3% or less, average crystal grain size 60 μm
The following final plate is obtained.

The method of manufacturing an aluminum alloy soft plate for deep drawing according to the second aspect of the present invention is characterized in that:
%, Mn 0.7-1.5%, Mg 0.1-0.7%, Si 0.01-0.5%, Cu 0.01-
0.5%, Cr 0.01-0.5%, Zr 0.01-
0.5%, V0.01-0.5%, Ti0.005-
An alloy containing one or more selected from 0.2% and B 0.0001 to 0.05%, the balance being Al and unavoidable impurities is used as a raw material.
After performing the homogenization treatment at a temperature of 0 ° C. or higher, hot rolling is performed by setting the hot rolling start temperature within a range of 380 to 580 ° C. and the hot rolling end temperature within a range of 200 to 300 ° C. % After the first cold rolling at a rolling rate of
Intermediate annealing is performed at a temperature in the range of 250 to 500 ° C. for 0.5 hours or more, and then at a rolling reduction of 50% or more,
Next cold rolling is performed, and as final annealing, 50 ° C /
Heating to a temperature in the range of 350 to 600 ° C. at a heating rate of min or more, and performing continuous annealing without holding or holding for 10 minutes or less, whereby the tensile strength is 120 MPa or more,
Elongation 15% or more, deep drawing ear ratio 3% or less, average crystal grain size 6
It is characterized by obtaining a final plate of 0 μm or less.

Further, the method of manufacturing an aluminum alloy soft plate for deep drawing according to the third aspect of the present invention is provided.
For the final plate obtained by any one of the methods described above, either alkali washing using a sodium silicate-based or sodium phosphate-based or caustic soda-based washing solution, or acid washing using a sulfuric acid-based washing solution, It is characterized by performing one or both.

According to a fourth aspect of the present invention, there is provided a method for producing an aluminum alloy soft plate for deep drawing, wherein a phosphoric acid chromate treatment is performed as a chemical conversion treatment after the alkali cleaning or the acid cleaning according to the third aspect. It is assumed that.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, the reasons for limiting the composition of the alloy used in the method of the present invention will be described.

Fe: Fe is a basic alloy element in the alloys of the present invention, and is an Al--Fe alloy,
It is an important element that forms an l-Fe-Si or Al-Fe-Mn intermetallic compound and contributes to improving strength, formability, surface quality, and the like through refinement of crystal grains. Further, by appropriately controlling the solid solution and precipitation of Fe and the size and distribution of the intermetallic compound, it is possible to suppress the deep drawing ear ratio of the final plate to a low value. Here, if the Fe content is less than 0.3%, the above-mentioned effects cannot be sufficiently obtained, and
On the other hand, if it exceeds 0.9%, the deep drawing ear ratio in the direction of 45 ° with respect to the rolling direction increases, and the formability also decreases. Therefore, the amount of Fe was set in the range of 0.3 to 0.9%.

Mg: Mg is also an important element in the alloy used in the present invention.
The strength can be expected to be improved by increasing the amount of work hardening based on the solid solution of Mg, and is therefore an element indispensable for improving the strength of the material. Also, Mg has a large effect of increasing the dislocation density during processing, and is therefore effective for making recrystallized grains finer. Here, if the Mg content is less than 0.1%, the above-mentioned effects cannot be sufficiently obtained. On the other hand, if the Mg content exceeds 0.7%, the strength can be increased, but the adhesion to the resin film is deteriorated and the resin laminated aluminum is deteriorated. There is a possibility that the corrosion resistance of the foil may be reduced, and furthermore, a poor appearance due to a Luders line may occur after deep drawing. Therefore Mg
The amount was in the range of 0.1-0.7%.

Mn: Mn is an effective element contributing to the improvement of the balance between strength and ear ratio. In particular, Mn forms an intermetallic compound with Al and Fe so that Mn is 0% with respect to the rolling direction during recrystallization.
It is an indispensable element for suppressing ear development in the -90 [deg.] Direction and achieving a low ear rate. If the Mn content is less than 0.7%, the above effects cannot be sufficiently obtained, while if it exceeds 1.5%, a Mn-based primary intermetallic giant intermetallic compound is generated and the formability is significantly impaired. Therefore, the Mn content is set in the range of 0.7 to 1.5%.

Further, alloys used in the method of the present invention include:
In order to improve strength, formability and surface quality through grain refinement, Si, Cu, Cr, Zr,
One or more selected from V, Ti, and B are added. The reasons for limiting the amounts of these selectively added elements will be described below.

Si: Si is an element that is often contained as an inevitable impurity even in ordinary aluminum alloys. However, by actively adding Si, it is possible to reduce the crystal grain size, improve the strength, and stabilize the ear ratio. effective. However, if the Si content is less than 0.01%, the above-mentioned effects cannot be sufficiently obtained, while if it exceeds 0.5%, the corrosion resistance is deteriorated. Therefore, when the Si content is positively added, the Si content is 0.01 to 0. 0.5%. Even when Si is not positively added, 0.0
Of course, less than 1% of Si is allowed as an unavoidable impurity.

Cu: Cu is also an element that is effective in reducing the crystal grain size, improving the strength, and stabilizing the ear ratio. Cu content is 0.01
%, These effects are not sufficiently obtained.
%, Corrosion resistance deteriorates. Therefore, when Cu is added, the amount of Cu is set in the range of 0.01 to 0.5%.

Cr, Zr, V: These elements are all effective elements for refining crystal grains and stabilizing the structure. Cr, Zr, and V are all added in an amount of 0.01.
If it is less than 0.5%, the above-mentioned effects cannot be sufficiently obtained. On the other hand, if both of them exceed 0.5%, not only the above-mentioned effects are saturated, but also a large intermetallic compound may be generated to adversely affect drawability. is there. Therefore, the amounts of Cr, Zr, and V added are all within the range of 0.01 to 0.5%.

Ti, B: In ordinary aluminum alloys, Ti is often added alone or in combination with B for refining ingot crystal grains, and the alloy used in the method of the present invention is also used in the present invention. A small amount of Ti may be added alone or in combination with a small amount of B. However, if the Ti content is less than 0.005%, the above effects cannot be obtained.
If the i content exceeds 0.2%, a huge Al-Ti intermetallic compound is crystallized to inhibit the formability, so the range of the Ti content was made 0.005 to 0.2%. If B is added together with Ti, the effect of refining the ingot crystal grains is improved. When B is added together with Ti, the amount of B is 0.0001.
%, The effect of adding B cannot be obtained. On the other hand, if it exceeds 0.05%, coarse particles of Ti-B series are generated and formability is impaired. Therefore, when B is added, the amount of B added is 0.0001.
Within the range of ０．０５0.05%.

In addition to the above elements, Al and unavoidable impurities may be used.

Next, the manufacturing process in the method of the present invention will be described.

First, a molten alloy having the above-described composition is melted according to a conventional method, and then cast according to a conventional method such as a DC casting method to obtain an ingot. 530 for the resulting ingot
Perform homogenization at a temperature of at least ℃. This homogenization process
In addition to eliminating segregation of elements generated during casting,
It is indispensable to adjust the solid solution and precipitation of Fe and Mn, and the size and distribution of these intermetallic compounds to improve the formability and obtain a low ear ratio of the final plate. Temperature of homogenization process is 5
If the temperature is lower than 30 ° C., these effects cannot be sufficiently obtained.
The lower limit of the temperature of the homogenization treatment was 530 ° C. or higher. The upper limit of the homogenization temperature is not particularly limited, but is generally preferably 630 ° C. or lower so that eutectic melting does not occur. The time for the homogenization treatment is not particularly limited, but usually about 1 to 48 hours is appropriate.

The ingot after the homogenization treatment is subjected to hot rolling. This hot rolling is an important step that has a significant effect on the mechanical properties, surface quality, and ear ratio of the final sheet. When the hot rolling start temperature is lower than 380 ° C., recrystallization during hot rolling is suppressed, and not only the subsequent adjustment of the ear ratio becomes difficult, but also the hot rolling end temperature (rising temperature).
And the surface quality may be degraded due to poor lubrication, water corrosion and the like. On the other hand, the hot rolling start temperature is 580
If the temperature exceeds ℃, the crystal grains formed during the hot rolling may be coarsened and the surface quality may be deteriorated. Therefore, the hot rolling start temperature needs to be in the range of 380 to 580 ° C. When the hot rolling end temperature is higher than 300 ° C., non-uniform coarse crystal grains may be formed. On the other hand, when the hot rolling end temperature is lower than 200 ° C., poor lubrication and water corrosion may occur. is there. Therefore, the hot rolling end temperature must be in the range of 200 to 300 ° C.

After the completion of the hot rolling, 50% before the intermediate annealing.
The primary cold rolling is performed at the above rolling ratio. Such primary cold rolling at a rolling ratio of 50% or more before the intermediate annealing is not only necessary to obtain a fine recrystallized grain structure during the subsequent intermediate annealing, but also due to fluctuations in hot rolling conditions. It is also indispensable to eliminate the resulting variation in mechanical properties. Here, if the rolling reduction of the primary cold rolling is less than 50%, the above effects cannot be sufficiently obtained. Although the upper limit of the primary cold rolling reduction is not particularly defined, it is usually preferably 90% or less from the viewpoint of securing the secondary cold rolling reduction.

After the first cold rolling, intermediate annealing is performed using a batch furnace. This intermediate annealing not only makes the material completely recrystallize and improves the formability of the final sheet, but also suppresses the 45 ° direction ear in deep drawing, and is indispensable for reducing the ear rate of the final sheet.

Here, if the annealing temperature of the intermediate annealing is lower than 250 ° C., recrystallization hardly proceeds, and it takes a remarkably long time to reach a completely recrystallized state.
On the other hand, if the annealing temperature is higher than 500 ° C., not only the crystal grains are coarsened, but also the oxide film is formed thick on the surface, which may lower the adhesion to the resin film. Therefore, the intermediate annealing temperature needs to be in the range of 250 to 500 ° C. In order to reliably suppress the formation of a surface oxide film in the intermediate annealing, the annealing temperature is set to 430.
C. or lower, and annealing in an inert gas atmosphere is preferred. If the heating and holding time in the intermediate annealing is less than 0.5 hour, it may be difficult to obtain a uniform complete recrystallized structure. Therefore, the annealing time is 0.5 hour or more. The upper limit of the annealing time is not particularly limited, but is generally preferably 48 hours or less from the viewpoint of economy and the like.

After the intermediate annealing, a secondary cold rolling at a rolling reduction of 50% or more is performed. The secondary cold rolling at a rolling reduction of 50% or more is necessary not only to obtain a required sheet thickness, but also to obtain a fine grain structure at the time of final annealing thereafter. It is also necessary to minimize the height of the ears generated during drawing. If the rolling ratio of the secondary cold rolling is less than 50%, these effects cannot be sufficiently obtained, and therefore, the rolling ratio of the secondary cold rolling needs to be 50% or more. Although the upper limit of the rolling reduction in the secondary cold rolling is not particularly limited, it is usually preferably 98% or less from the viewpoint of stability of ear ratio.

After the secondary cold rolling, final annealing is performed by batch annealing using a batch furnace at a heating rate of 100 ° C./hour or less or continuous annealing at a heating rate of 50 ° C./min or more using a continuous annealing furnace. Do. This final annealing is necessary not only to completely recrystallize the material and improve the formability as a soft material, but also to suppress the ear rate to 3% or less.

Here, in the case of final annealing using a batch furnace, if the heating and holding temperature is lower than 250 ° C., recrystallization is difficult to proceed, and a remarkably long time is required until a complete recrystallization state is reached. At a high temperature exceeding 500 ° C., on the other hand, at a high temperature exceeding 500 ° C., not only the crystal grains become coarse, but also a thick oxide film is formed on the surface, which may lower the adhesion to the resin film. If the heating and holding time in the final annealing by the batch furnace is less than 0.5 hour, it is difficult to obtain a uniform complete recrystallized structure. Therefore, when the final annealing is batch annealing, the temperature is kept at a temperature in the range of 250 to 500 ° C. for 0.5 hour or more. Although the upper limit of the holding time in this case is not particularly limited, it is usually preferable to set it within 48 hours from the viewpoint of economy.

On the other hand, when the final annealing is performed by a continuous annealing method (CAL) of rapid heating and high-temperature short-time heating, the crystal grains can be made finer than when batch annealing is applied. When the final annealing is performed by continuous annealing as described above, it is difficult to obtain a completely recrystallized structure at a heating temperature of less than 350 ° C. On the other hand, at a high temperature exceeding 600 ° C., crystal grains become coarse and eutectic Melting may occur. 350-600 in continuous annealing
If the holding time in the range of ° C. exceeds 10 minutes, the above-mentioned effect is saturated and the economy is impaired. Therefore, the conditions for applying continuous annealing to the final annealing are 350 to 600 ° C.
Was heated to a temperature within the range described above to maintain no temperature or hold for 10 minutes or less.

The final sheet obtained by performing the final annealing as described above has a tensile strength of 120 MPa or more, an elongation of 15% or more, a deep drawing ear ratio of 3% or less, and an average grain size of 60 μm.
m. Here, the tensile strength is 12
If it is less than 0 MPa, it is not possible to sufficiently cope with a reduction in thickness due to insufficient strength, and it is difficult to ensure sufficient handleability during transportation of products such as containers. If the elongation is less than 15%, it cannot be said that the composition has sufficient moldability. Further, when the ear ratio exceeds 3%, the yield in deep drawing cannot be sufficiently improved. If the average crystal grain size exceeds 60 μm, the surface quality such as surface roughness will be reduced during molding.

The final sheet obtained after the final annealing obtained as described above may be directly subjected to lamination with a resin film and further to deep drawing. However, the final treatment includes alkali cleaning and acid cleaning. If one or both of them are given, or if a phosphate chromate treatment is given as a chemical conversion treatment after alkali washing or acid washing, the adhesion of the resin film is improved, and the corrosion resistance as a resin laminated aluminum foil is improved. It can be further improved.

Here, as the alkali cleaning, a sodium silicate-based or sodium phosphate-based or caustic soda-based alkali cleaning solution can be used. In the case of using any of sodium silicate, sodium phosphate, and caustic soda, a cleaning solution having a sodium silicate, sodium phosphate, or caustic soda concentration of 0.5 to 5% and a solution temperature of 30 to 9 are used.
It is desirable to wash at 0 ° C. for 3 to 30 seconds.

On the other hand, in the acid cleaning, a sulfuric acid concentration of 5 to 15 is used.
It is appropriate to wash at a solution temperature of 30 to 80 ° C. for 3 to 30 seconds using a sulfuric acid washing solution of 10%.

By performing the alkali cleaning or the acid cleaning as described above, the surface of the final plate can be roughened, and the adhesion to the resin film can be improved by a mechanical anchor effect.

Further, in the case of performing a phosphoric acid chromate treatment as a chemical conversion treatment after performing the above alkali washing or acid washing, a mixed solution having a chromium phosphate concentration of 1 to 5% and a hydrofluoric acid concentration of 0.1 to 3%. At 20-70 ° C.
It is preferable to apply the coating at a coating amount of 1 to 40 mg / m ² for up to 20 seconds, and then to perform baking at 150 to 250 ° C. for 1 minute or less. If the chemical conversion film is formed by performing a phosphoric acid chromate treatment after the alkali washing or the acid washing as described above, the adhesion to the resin film can be further improved.

[0038]

EXAMPLES Alloys A1 to A3 within the composition range of the present invention and alloy B outside the composition range of the present invention shown in Table 1
Each of 1 and B2 is cast by a DC casting method according to a conventional method, and after the obtained ingot is subjected to a homogenization treatment, hot rolling is performed, and further, primary cold rolling is performed on the rolled plate. Then, after performing intermediate annealing in a batch furnace, secondary cold rolling is performed, and then batch annealing (BA
F) or final annealing by continuous annealing (CAL). Table 2 shows the detailed conditions of these steps. Table 2
In the table, “0 sec” in the column of the final annealing condition indicates that cooling was performed immediately after reaching a predetermined temperature without holding.

The mechanical properties (tensile strength, proof stress, elongation) and the average crystal grain size of the final plate obtained as described above are examined, and the ear ratio and the direction of ear generation are determined by performing deep drawing. Examined. The results are shown in Table 3. Here, the ear ratio and the ear ratio when a cup deep drawing test was performed under the conditions of a punch diameter of 32 mmφ and a blank diameter of 56 mmφ were examined.

Further, a part of the final plate obtained as described above is subjected to alkali washing or acid washing, and a part of the alkali-washed plate is subjected to a phosphoric acid chromate treatment as a chemical conversion treatment. Table 3 shows the results of the examination of the corrosion resistance. The alkaline washing conditions were as follows: a sodium phosphate-based washing solution was used, and a concentration of 2 was used.
%, The temperature was 70 ° C., and the time was about 13 seconds. The acid washing conditions were as follows: after the above alkali washing, an acid washing solution having a sulfuric acid concentration of 10% was used at a temperature of 50 ° C. for a time of about 13 seconds. Further, the phosphoric acid chromate treatment conditions as the chemical conversion treatment are as follows: after the above alkali washing, using a mixed solution of chromium phosphate 2% and hydrofluoric acid 0.5% at 40 ° C. for about 5 seconds, coating amount 10 mg / m ² ,
The baking temperature was 170 ° C. and the baking time was 10 seconds. As for the corrosion resistance, a 50-μm-thick polyolefin-based resin film was stuck to the surface of the untreated plate and the plate subjected to each treatment, and then cross-cut and subjected to a one-month salt water spray test to give a five-point evaluation. Was performed. Regarding the grade evaluation of the corrosion resistance, 3 or more was evaluated as the acceptable level and 5 was evaluated as the best.

[0041]

[Table 1]

[0042]

[Table 2]

[0043]

[Table 3]

In Tables 1 to 3, all of the production numbers 1 to 3 are examples of the present invention in which the composition of the alloy is within the range specified by the present invention and the manufacturing process conditions are also within the range specified by the present invention. In all of these cases, the strength and elongation are good, and the tensile strength is 120 MPa or more, and the elongation is 15% or more. The ear ratio is 3% or less, and the crystal grain size is low. Fine and average grain size 6
The condition of 0 μm or less was sufficiently satisfied, and the corrosion resistance after lamination with the resin film was also good.

On the other hand, Production No. 4 is a comparative example in which the composition of the alloy is within the scope of the present invention but the production process deviates from the present invention, that is, a comparative example in which the intermediate annealing and the secondary cold rolling were not performed. is there. In this case, although the strength was high, the ear ratio was as high as 4.6%.

Production No. 5 is a comparative example using an alloy outside the component composition range of the present invention, that is, an alloy containing substantially no Mn and Mg and having an excessively large amount of Si. Although the conditions defined in the invention were satisfied, the strength of the final plate was low.

Production No. 6 is also a comparative example using an alloy outside the component composition range of the present invention, particularly an alloy containing a large amount of Mg exceeding 0.7%. Was satisfied, but the adhesion to the resin film was poor, and therefore, it was found that the corrosion resistance in a state where the resin was laminated was poor.

Regarding the corrosion resistance after resin lamination, acid washing or alkali washing,
It is apparent from Table 3 that the chemical conversion treatment has been improved.

[0049]

As is apparent from the above-described embodiment, according to the method of the present invention, the strength and the formability are excellent, the deep drawing ear ratio is stably low, and the surface quality is good. In addition, it is possible to reliably and stably obtain an aluminum alloy soft plate having good adhesion to the resin film and good corrosion resistance when laminated with the resin film.
Therefore, the method of the present invention is particularly suitable for the production of a soft plate used for a retort container, a vessel, a cap, etc., which is laminated with a resin and subjected to deep drawing.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C22F 1/00 684 C22F 1/00 684 686 686 691 691A 691B 694 694A 694B

Claims (4)

[Claims] 1. An alloy containing 0.3 to 0.9% of Fe (% by weight, the same applies hereinafter), 0.7 to 1.5% of Mn and 0.1 to 0.7% of Mg, and 0.01 to 0.5% of Si. %, Cu0.01
~ 0.5%, Cr0.01 ~ 0.5%, Zr0.01 ~
0.5%, V0.01-0.5%, Ti0.005-
An alloy containing one or more selected from 0.2% and B 0.0001 to 0.05%, the balance being Al and unavoidable impurities is used as a raw material.
After performing the homogenization treatment at a temperature of 0 ° C. or higher, hot rolling is performed by setting the hot rolling start temperature within a range of 380 to 580 ° C. and the hot rolling end temperature within a range of 200 to 300 ° C. % After the first cold rolling at a rolling rate of
Intermediate annealing is performed at a temperature in the range of 250 to 500 ° C. for 0.5 hours or more, and then at a rolling reduction of 50% or more,
Next cold rolling is performed, and as final annealing, 100 ° C.
/ Hr is heated to a temperature in the range of 250 to 500 ° C. at a temperature rising rate of not more than / hr, and is subjected to batch annealing for holding for 0.5 hour or more.
As described above, a method for producing an aluminum alloy soft plate for deep drawing, characterized by obtaining a final plate having a deep drawing ear ratio of 3% or less and an average crystal grain size of 60 μm or less. 2. Fe 0.3-0.9%, Mn 0.7-
1.5%, Mg 0.1-0.7%, and further Si
0.01-0.5%, Cu 0.01-0.5%, Cr
0.01-0.5%, Zr 0.01-0.5%, V0.
01-0.5%, Ti 0.005-0.2%, B0.0
An alloy containing at least one selected from 001 to 0.05%, the balance being Al and unavoidable impurities is used as a material, and the ingot is subjected to a homogenization treatment at a temperature of 530 ° C. or more. After the application, the hot rolling start temperature is set to 380 to 58
After hot rolling is performed at a hot rolling end temperature of 200 to 300 ° C. within a range of 0 ° C., and primary cold rolling is further performed at a rolling reduction of 50% or more, a range of 250 to 500 ° C. Intermediate annealing at a temperature within 0.5 hours or more is performed, then secondary cold rolling is performed at a rolling rate of 50% or more, and final annealing is performed at a heating rate of 50 ° C./min or more at 350 to 600 ° C. Heating to a temperature in the range of 0 ° C. to perform continuous annealing without holding or holding for 10 minutes or less, whereby the tensile strength is 120 MPa or more, the elongation is 15% or more,
A method for producing an aluminum alloy soft plate for deep drawing, wherein a final plate having a deep drawing ear ratio of 3% or less and an average crystal grain size of 60 μm or less is obtained. 3. An alkali cleaning using a sodium silicate-based, sodium phosphate-based or caustic soda-based alkaline cleaning solution, and a sulfuric acid-based acid on the final plate obtained by the method according to claim 1. A method for producing an aluminum alloy soft plate for deep drawing, characterized by performing one or both of acid cleaning using a cleaning liquid. 4. A method for producing an aluminum alloy soft plate for deep drawing, wherein a phosphoric acid chromate treatment is performed as a chemical conversion treatment after the alkali cleaning or the acid cleaning according to claim 3.