JPH0860283A - Aluminum alloy plate for DI can body and method for producing the same - Google Patents

Abstract

(57) [Summary] [Purpose] As an aluminum alloy hard plate for DI can bodies, it not only excels in strength and DI formability, but also DI
Provided is a plate excellent in formability (necking workability, flange workability, seaming workability) of a can edge portion after processing and paint baking, and a method for producing the plate. [Composition] Claims 1 and 2: Mg 0.5 to 1.8%, Mn
0.5-1.8%, Fe0.3-0.8%, Si0.1
5 to 0.8%, Fe / Si ratio of 2 or less, and a trace amount of Ti
(And B), and if necessary, a small amount of C
u, Cr and Zn are contained, and the balance is substantially made of Al, and the α-conversion rate of the Al-Mn-based intermetallic compound is 30% or more,
An Al alloy plate in which intermetallic compounds of 0.5 to 2 μm on the plate surface are present at 10000 pieces / mm ² or more. Claim 3: After casting the alloy, when performing homogenizing treatment at 530 to 610 ° C for 2 to 24 hours, 450 to 50 in the temperature rising process.
The rate of temperature rise in the temperature range of 0 ° C. is set to 70 ° C./hr or less, or intermediate holding is performed in that temperature range for 0.5 to 2 hours.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a can body for a two-piece aluminum can made by DI processing (drawing-ironing), that is, an Al-M used for an aluminum alloy DI can body.
Regarding g-Mn-based aluminum alloy hard plate, especially after DI processing and paint baking treatment, can furring edge (flange)
DI with good formability in flange processing etc.
The present invention relates to an aluminum alloy plate for a can body and a method for manufacturing the same.

[0002]

2. Description of the Related Art Generally, as a manufacturing process for a two-piece aluminum can, a can body material is subjected to DI drawing by deep drawing and ironing into a can body shape, and then trimmed to a predetermined size. After painting and baking, the neck of the can is necked (narrowing) and flanged (expanding), and the separately formed can lid (can end) is combined and seamed (rolled). The tightening process is usually performed.

By the way, as a can body for a conventional DI can,
JIS 3004 alloy and AA 3104 alloy, which are Al-Mg-Mn based alloys, are widely used. These alloys are excellent in ironing workability, and are suitable as DI can body materials because they show relatively good formability even when cold rolled at a high rolling rate to increase strength. It is said that.

[0004]

For the two-piece aluminum can, the material cost is reduced by further reducing the wall thickness.
There is a strong demand for weight reduction. In order to reduce the wall thickness as described above, it is desired to further increase the strength. Further, the DI can body material is required to have not only high strength but also good DI moldability, and further, necking, flanging, and seaming after molding the DI can body and applying baking treatment. Excellent formability in processing is also required. In particular, the can barrel edge is subjected to multi-stage, multi-type processing such as cold rolling in the material manufacturing process, DI molding during can barrel molding, necking processing after paint baking, flange processing, and seaming processing. Therefore, cracks are likely to occur during processing. Especially recently, the plate thickness of the can edge has become smaller as the can body becomes thinner.
As a result, the edges tend to break during flanging and seaming, which is why the flangeability of the can edge is
Improvement of seaming workability is strongly desired. Further, due to the demand for weight reduction of the can lid, it is desired to reduce the neck diameter of the can body. In this case, since it is necessary to increase the necking processing amount, it is possible to further improve the moldability of the can body edge portion. Is desired.

The present invention has been made in view of the above circumstances, and is not only excellent in strength and DI moldability, but particularly excellent in moldability of a neck portion of a can subjected to necking, flanging, or seaming. Another object of the present invention is to provide an aluminum alloy DI can body.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted extensive experiments and research to solve the above-mentioned problems, and as a result, appropriately selected the alloy component composition of the material and, at the same time, set the homogenization treatment conditions for the ingot. By optimizing the microstructure state, especially the dispersion state of the intermetallic compound, the aluminum alloy plate for a DI can body is excellent in the formability of the can body edge portion after DI processing and paint baking treatment. The inventors have found that the following can be obtained, and have completed the present invention.

Specifically, the aluminum alloy sheet according to the invention of claim 1 has Mg of 0.5 to 1.8% and Mn of 0.5 to 1.
8%, Fe 0.3-0.8%, Si 0.15-0.8%
And Fe / Si ratio is within the range of 2 or less,
Further, 0.005 to 0.20 as an ingot structure refiner
% Ti alone or in combination with 0.0001 to 0.05% B, the balance consisting of Al and inevitable impurities, and the Al-Mn-based intermetallic compound having an alpha conversion rate of 30% or more. In addition, the intermetallic compound in the range of 0.5 to 2 μm is present in the plate surface in an amount of 10000 / mm ² or more.

The aluminum alloy sheet according to the second aspect of the present invention has Mg 0.5 to 1.8%, Mn 0.5 to 1.8%, F
e 0.3-0.8%, Si 0.15-0.8%, Fe / Si ratio is within the range of 2 or less, and 0.005-0. 20% T
i alone or in combination with 0.0001-0.05% B, Cu 0.05-0.5%, C
It contains at least one of 0.05 to 0.3% of Zn and 0.1 to 0.5% of Zn, and the balance of Al and unavoidable impurities. Three
It is characterized in that the intermetallic compound is present in an amount of 0% or more and in the range of 0.5 to 2 μm on the plate surface in an amount of 10000 / mm ² or more.

Further, the method for producing an aluminum alloy plate for a DI can body according to claim 3 is such that Mg 0.5 to 1.8% and Mn 0.
5 to 1.8%, Fe 0.3 to 0.8%, Si 0.15
0.8%, Fe / Si ratio is within the range of 2 or less, and 0.005 as an ingot structure refiner.
0.20% Ti alone or 0.0001-0.
Contains in combination with B of 05%, and if necessary Cu
0.05-0.5%, Cr 0.05-0.3%, Zn
It contains one or more of 0.1 to 0.5% and the balance is A
After casting an alloy consisting of 1 and unavoidable impurities, 5
In performing the homogenizing treatment at 30 to 610 ° C. for 2 to 24 hours, the temperature range of 450 to 500 ° C. in the temperature raising process is continuously raised at a temperature raising rate of 70 ° C./hr or less, or within the temperature range. Hold for 0.5 to 2 hours, perform homogenization treatment, and then perform hot rolling and cold rolling to obtain Al-
The α-conversion rate of the Mn-based intermetallic compound is 30% or more, and the intermetallic compound within the range of 0.5 to 2 μm is 10000 on the plate surface.
It is characterized in that a rolled plate having a number of pieces / mm ² or more is obtained.

[0010]

In the aluminum alloy sheet for a DI can body of the present invention, basically, the alloy composition, especially the Fe / Si ratio,
The texture state, particularly the α-formation ratio of the Al-Mn-based intermetallic compound and the size and distribution density of the intermetallic compound are important. Only when these are within the predetermined range, can the excellent moldability of the can edge portion be achieved. Secure, at the same time high strength, good DI
Moldability can be obtained. Therefore, first, the reasons for limiting the composition of the alloy will be described.

Mg: Mg is an element which is effective for solid solution strengthening by itself, and is an essential element for improving strength. Furthermore, the addition of Mg is due to the coexistence of Si and Cu with Mg ₂ Si.
Alternatively, age hardening due to precipitation of Al-Cu-Mg phase can be expected. If the amount of Mg is less than 0.5%, its effect is small, while if it is added over 1.8%,
Since it becomes easy to work and harden, it deteriorates redrawability and ironing formability during DI processing. Therefore, the range of Mg is set to 0.5 to 1.8%.

Mn: Mn is an element effective in contributing to improvement in strength and formability. In particular, in the manufacturing process of the can body that is the subject of this invention, Mn is important because severe ironing is performed during DI molding. Emulsion type lubricants are usually used in ironing of aluminum plates, but when Mn-based crystallized substances are small, even if they have similar strength, the emulsion type lubricants alone lack lubrication ability. However, there is a possibility that appearance defects such as scratches and seizure called "goring" may occur. It is known that this phenomenon is affected by the size, amount, and type of crystallized substances, and Mn is indispensable for forming an appropriate Mn-based crystallized substance and improving the lubricating ability in ironing. It is an element. If the Mn content exceeds 1.8%, primary crystal giant intermetallic compounds of MnAl ₆ are generated, and conversely the formability is significantly impaired. If the Mn content is less than 0.5%, the solid lubricating effect of the Mn-based compound cannot be obtained. Therefore, the range of Mn is set to 0.5 to 1.8%.

Fe: Fe promotes crystallization and precipitation of Mn,
It is an element necessary for controlling the amount of Mn solid solution in the aluminum matrix and the dispersed state of the Mn-based insoluble compound. In order to obtain a proper compound dispersion state, F may be changed according to the amount of Mn added.
It is necessary to add e. When the Fe content is less than 0.3%, it is difficult to obtain a proper compound dispersion state, while when the Fe content is 0.8% or more, a primary crystal giant compound is likely to be generated due to the addition of Mn, and molding Remarkably impairs sex.
Therefore, the range of Fe is set to 0.3 to 0.8%.

Si: Si is A when coexisting with Fe.
It controls the morphology and distribution of the 1-Mn-based intermetallic compound. Further, addition of Si also contributes to age hardening due to precipitation of Mg ₂ Si-based compound. If the Si content is less than 0.15%, the effect cannot be obtained, and if it exceeds 0.8%, coarse intermetallic compounds increase, and age hardening deteriorates the ductility of the material and hinders formability. Therefore, the range of Si is 0.15 to 0.5
%.

Fe / Si ratio: In the present invention, Fe in the alloy is adjusted to optimize the morphology and distribution of the intermetallic compound.
Ratio of the amount (wt%) to the amount of Si (wt%), that is, Fe
The / Si ratio is extremely important. When the Fe / Si ratio exceeds 2, the α-formation of the Al—Mn-based intermetallic compound is delayed, and the distribution of the intermetallic compound tends to be rough, so that the fine particles of 0.5 to 2 μm as described later are produced. The distribution density of the intermetallic compound becomes low, and it becomes impossible to improve the formability of the can edge portion. Therefore, it is necessary to set the Fe / Si ratio to 2 or less.

Ti, B: In ordinary aluminum alloys, a small amount of Ti or Ti and B is added for refining the ingot crystal grains. In the present invention, too, a small amount of Ti, or Ti and B is added. B is added. However, if the Ti content is less than 0.005%, the effect cannot be obtained, and if it exceeds 0.20%, primary TiAl ₃ crystallizes and hinders formability, so the Ti content is 0.005 to 0.20.
Within the range of%. If B is added together with Ti, the effect of refining the ingot crystal grains is improved. However, B together with Ti
When B is added in an amount of less than 0.0001%, it has no effect, and when it exceeds 0.05%, coarse particles of TiB ₂ are mixed and impair the formability.
It was set within the range of 0.05%.

Further, in the aluminum alloy plate of the invention of claim 2, Cu0.05-0.5%, Cr0.05
.About.0.3%, Zn 0.1 to 0.5%, and one or more of them are added. All of these elements are elements that contribute to improving the strength, and are added to further improve the strength. Each of these elements will be further described.

Cu: Cu contributes to the strength improvement by utilizing the precipitation hardening by precipitating Al-Cu-Mg type precipitates during the baking treatment of the coating by being solution-treated during annealing. If the Cu content is less than 0.05%, the effect cannot be obtained. On the other hand, if Cu is added in excess of 0.5%, age hardening is easily obtained, but it becomes too hard and hinders formability. At the same time, the corrosion resistance deteriorates. Therefore, when Cu is added, the Cu amount range is 0.05 to 0.5%.
It is preferable that

Cr: Cr is also an element effective for improving strength, but if it is less than 0.05%, its effect is small, and 0.3%.
If it exceeds the range, the formation of huge crystallized substances causes a decrease in moldability, which is not preferable. Therefore, when adding Cr, Cr
The amount range is preferably 0.05 to 0.3%.

The addition of Zn: Zn contributes to the strength improvement by aging precipitation of Mg ₂ Zn ₃ Al ₂ , but the effect is not obtained if it is less than 0.1%, and it contributes to the strength if it exceeds 0.5%. There is no problem, but it deteriorates the corrosion resistance. Therefore, when adding Zn, the range of the amount of Zn is 0.1 to 0.5%.
It is preferable that

The balance of each of the above components may be Al and unavoidable impurities, but regarding Cu, Cr and Zn,
Needless to say, the amount of impurities may be less than the above lower limit.

In the aluminum alloy sheet for DI can bodies according to the first and second aspects of the invention, not only the alloy composition as described above is satisfied, but also Al-Mn in the final sheet state.
The alpha conversion rate of the intermetallic compound is 30% or more, and the intermetallic compound of 0.5 to 2 μm is 10000 / mm on the plate surface.
It must exist at a density of ² or higher. Here, the α-formation ratio of the Al-Mn-based intermetallic compound means αAl (Mn among the Al-Mn-based intermetallic compounds that have been crystallized and precipitated.
Fe) means the proportion occupied by Si phase. That is, Al-
In an Mn-Mg (-Fe) -based alloy, Al ₆ Mn, Al ₆ MnFe, etc. are generally crystallized as intermetallic compounds during casting, but when Si is contained, these Al ₆ Mn phases and Al ₆ MnFe phase is αA by heat treatment
It is transformed into the 1MnSi phase and the αAlMnFeSi phase. These αAlMnSi phase, αAlMnFeSi phase or further αAlFeSi phase is generally used as αAl (MnFe) S
Although expressed as i, the proportion of such αAl (MnFe) Si phase in the total Al—Mn-based intermetallic compound is referred to as the α-ratio, and it is necessary that this proportion is 30% or more.

As described above, Al ₆ M crystallized during casting
n, Al ₆ MnFe is usually coarse, but by subjecting the ingot to an appropriate homogenizing treatment as described later, these Al-Mn-based intermetallic compounds become α, and αAl
It becomes a (MnFe) Si phase. And when making this alpha
The l-Mn-based intermetallic compound becomes finer, and the fine intermetallic compound disperses the processing strain in the process of further performing DI processing, paint baking processing, necking processing, flange processing, and seaming processing on the final plate, The workability (necking workability, flange workability, seaming workability) of the can body edge is improved. Therefore, it is possible to improve the formability of the can edge portion by miniaturizing the intermetallic compound by converting the Al-Mn-based intermetallic compound into α. Further, since the αAl (MnFe) Si phase is harder than the Al ₆ (MnFe) phase, by increasing the α conversion rate, the solid lubrication effect of the intermetallic compound during DI processing becomes larger, and the ironing workability is improved. To do. Here, if the α-formation ratio is less than 30%, the solid lubricating ability of the intermetallic compound cannot be sufficiently obtained, and not only good ironing workability cannot be obtained, but also the Al-Mn-based intermetallic compound is sufficiently miniaturized. It becomes difficult to distribute the intermetallic compound of 0.5 to 2 μm at a density of 10000 pieces / mm ² or more as described later, and as a result, sufficient moldability of the can edge portion is obtained. Cannot be improved.

Further, the size and distribution density of the intermetallic compound in the final plate will be described.

The intermetallic compound on the surface of the plate after the final rolling has a different contribution to the can making characteristics depending on its size and distribution. For example, coarse particles of 15 μm or more have a large strain concentration at the time of DI processing and are likely to be the starting point of breakage. If the distribution density is about 50 pieces / mm ² or more and the area ratio exceeds 1%, can breakage at DI processing, Furthermore, cracking becomes noticeable during francy processing. On the other hand, if the particles of about 2 to 15 μm are uniformly dispersed, the ironing workability can be improved by the solid lubricating effect during DI processing, but the workability of the can edge portion such as the flange workability can be improved. Does not contribute much to improvement. On the other hand, a fine intermetallic compound of 0.5 to 2 μm does not contribute so much to the solid lubrication effect, but it has an effect of evenly dispersing the working strain during the working of the can edge portion, and particularly the flange workability. The seaming workability can be improved. In order to exert such effects, 0.5 to 2
It is necessary that 10000 / mm ² or more of the intermetallic compound of μm exists, and if it is less than 10000 / mm ² , the strain is localized and the workability of the can edge portion deteriorates.

In the present invention, only intermetallic compounds of 0.5 to 2 μm are specified, but this can be easily observed with an optical microscope and surely contributes to the improvement of moldability of the can edge. Is an intermetallic compound having a diameter within the range of 0.5 to 2 μm. An extremely fine intermetallic compound of less than 0.5 μm also contributes to the improvement of the can edge forming property to some extent, but an intermetallic compound of less than 0.5 μm is difficult to observe with an optical microscope, and in practice, it is less than 0.5 μm. 5 to 2 μm
When the distribution of the intermetallic compound of 1 is 10,000 / mm ² or more, good moldability of the can edge portion can be obtained without being significantly affected by the number of intermetallic compounds of less than 0.5 μm. Intermetallic compounds of less than 0.5 μm were not specified. On the other hand, an intermetallic compound of more than 2 μm and 15 μm or less contributes to the improvement of DI processability as described above, but if it is a DC cast material containing Mn within the composition range of the present invention, it is necessary for DI process. Minimal amount 2-15
An intermetallic compound having a size of μm can be sufficiently obtained, and a large amount of particles of an intermetallic compound having a size of more than 15 μm can be produced in such a large amount as to cause a problem unless the component composition conditions and the manufacturing process conditions specified in the present invention are applied. Therefore, intermetallic compounds with a size of more than 2 μm were not specified. However, the number of intermetallic compound particles of more than ² μm and less than 15 μm is preferably 2000 / mm ² or more, and the number of intermetallic compound particles of more than 15 μm is 10 / m 2.
It is preferably m ² or less.

Next, the manufacturing process in the present invention will be described together with its operation.

First, an aluminum alloy ingot having the above-described composition is cast by a DC casting method (semi-continuous casting method) according to a conventional method. The obtained ingot is homogenized. This homogenization treatment not only homogenizes the composition and structure of the ingot, but also crystallizes Al in the ingot.
It is important to control the α-ization of the —Mn-based intermetallic compound and create an appropriate dispersed state of the intermetallic compound, and it is particularly important to control the temperature rising process. That is, for the original purpose for homogenization, it is necessary to hold at 530 to 610 ° C. for 2 to 24 hours, but the Al—Mn-based intermetallic compound should be kept at its α
In order to finally obtain the intermetallic compound dispersed state as described above by a-gelatinization so that the conversion rate becomes 30% or more, in the temperature rising process for reaching the holding temperature of 530 to 610 ° C. Temperature range of 450-500 ℃ 70 ℃ /
It is necessary to continuously raise the temperature at a temperature rising rate of h or less, or to hold (intermediate holding) for 0.5 to 2 hours within the temperature range of 450 to 500 ° C. in the above temperature rising process. The temperature rising rate in the temperature range of 450 to 500 ° C is 70
C./h is exceeded or the intermediate holding in the temperature range of 450 to 500.degree. C. is less than 0.5 hours, sufficient .alpha. Conversion of the Al--Mn based intermetallic compound does not proceed, resulting in deterioration of DI processability. At the same time, the distribution of intermetallic compounds tends to become rough. Also, the intermediate holding in the temperature range of 450 to 500 ° C is 2
Even if the time is exceeded, the effect of alpha conversion due to intermediate holding is saturated and it becomes uneconomical.

During the temperature raising process of the homogenization treatment, 450
When the temperature range of ˜500 ° C. is raised at a temperature rising rate of 70 ° C./h or less, the residence time in the temperature range of 450˜500 ° C. is about 43 minutes or longer. On the other hand, when performing intermediate holding for 0.5 hours or more in the temperature range of 450 to 500 ° C in the temperature raising process of the homogenization treatment, before and after the intermediate holding (from 450 ° C to the intermediate holding temperature, and from the intermediate holding temperature to 500 ° C). )
Considering the rate of temperature rise, the residence time in the temperature range of 450 to 500 ° C. is almost equal to or longer than that in the case of continuous temperature rise without intermediate holding. For example, when the temperature is raised at 200 ° C./h and held for 0.5 hours or more in the middle, the residence time is 45 minutes or more, and when the temperature is raised at 100 ° C./h and held for 0.5 hours or more in the middle, it is 1 hour. The residence time is as above. Therefore 4
Considering the total residence time from 50 ° C to 500 ° C,
Even in the case of intermediate holding for 0.5 hours or more, it is clear that the same effect as continuous heating at a heating rate of 70 ° C./h or less can be obtained.

The reaching / holding temperature of the homogenization treatment is 530.
If it is less than ℃, the effect of homogenization becomes insufficient, and Al-M
The alpha conversion of the n-based intermetallic compound is also insufficient. Meanwhile, 610 ° C
If it exceeds, local dissolution due to eutectic melting occurs. Further, even if the time required for reaching and holding the homogenization treatment is less than 2 hours, sufficient homogenization and α-formation effects cannot be obtained, while if it exceeds 24 hours, the economical efficiency is only impaired.

After the temperature raising process is appropriately controlled and the homogenizing process is performed as described above, hot rolling is performed. This hot rolling may be performed according to a conventional method, but the hot rolling finish temperature is preferably set in the range of 250 to 330 ° C.
When the hot rolling finish temperature is less than 250 ° C., recovery of dislocations does not proceed sufficiently after hot rolling, and re-crystallized grains having a cube orientation effective for lowering the deep drawing edge are formed by subsequent annealing. Buds (buds in the cube direction) are no longer generated,
In addition, rollability is also reduced. On the other hand, the hot rolling finish temperature is 330
If the temperature exceeds ℃, recovery of dislocations proceeds excessively, and a coarse hot-rolled structure tends to remain, so that recrystallization by subsequent annealing requires high-temperature treatment, and recrystallized grains are Not only becomes coarse, but harmful re-crystallized grains in the R direction, which raises the deep drawing ear, are likely to be generated.

After hot rolling, annealing is carried out if necessary. The purpose of this annealing is to uniformly recrystallize the hot rolled structure. This annealing may be carried out according to a conventional method, but in the case of batch annealing, it is general to heat to 300 to 420 ° C. and hold for 0.5 to 10 hours, and in the case of continuous annealing, it is 4
No retention or retention within 10 at 50 to 620 ° C. is common. In the case of batch annealing, a homogeneous recrystallized structure cannot be obtained at temperatures lower than 300 ° C., and if the temperature exceeds 420 ° C., oxidation of the plate surface becomes severe and DI processability deteriorates, and the appearance quality after DI processing deteriorates. Further, even if the holding time is less than 0.5 hours, a homogeneous recrystallized structure cannot be obtained, and 10
Exceeding time only impairs economics. In the case of continuous annealing, a homogeneous recrystallized structure cannot be obtained below 450 ° C,
If it exceeds 620 ° C., melting will occur, and if it exceeds 10 minutes, oxidation of the plate surface will proceed and the economy will be impaired.

When recrystallization is uniformly generated by hot rolling, that is, when the material is self-annealed and uniformly recrystallized by the retained heat during winding of the hot rolled sheet or in the subsequent cooling process, Annealing for recrystallization may not be performed again after hot rolling. Further, in order to make the recrystallized structure after annealing more uniform, cold rolling (primary cold rolling) may be performed before annealing.

The annealed plate is subjected to cold rolling (final cold rolling) to a required plate thickness. As the rolling ratio in this cold rolling is higher, sufficient strength can be obtained, and the working structure can be uniformly strengthened to improve the necking workability after coating baking treatment, the flange workability, and the seaming workability, Usually, it is desirable that the rolling rate is at least 50% or more, but more optimally, the rolling rate is 80% or more.

After cold-rolling to a desired plate thickness, it may be directly subjected to DI processing, but if necessary, final annealing is carried out at 100 to 200 ° C. for about 0.5 to 5 hours. As a result, the ductility can be restored and the deep drawability can be further improved.

As described above, with respect to an aluminum alloy having an appropriate component composition, by appropriate control of the production process, in particular, the temperature rising process in the ingot homogenization treatment, the Al-
It is possible to obtain a plate in which the Mn-based intermetallic compound has an α-conversion rate of 30% or more and the dispersion density of the intermetallic compound of 0.5 to 2 μm on the plate surface is 10000 / mm ² .

[0037]

EXAMPLES For each of the alloys Nos. A to D in Table 1, DC casting was performed according to a conventional method, and homogenization treatment was performed under the conditions shown in Table 2.
Hot rolling was performed, and immediately or if necessary, primary cold rolling was performed, followed by annealing, and final cold rolling to prepare a DI can body thin sheet having a sheet thickness of 0.30 mm.

With respect to the obtained thin plate, microscopic observation of the plate surface was carried out to measure the α-formation ratio of the Al-Mg type intermetallic compound, and the size and distribution of the intermetallic compound particles were examined with an image processing apparatus. The results are shown in Table 3. In addition, as a characteristic for the can body, the DI formability of the base plate was examined, and the proof stress after heat treatment at 200 ° C. for 20 minutes assuming coating baking treatment was measured, and further as the formability of the can body edge part, Necking workability, flange workability and seaming workability were investigated, and the results are also shown in Table 3. Here, as an evaluation of DI formability, the body manufacturer's second ironing die was removed and continuous severe ironing was performed for 1000 times.
The state of occurrence of broken cans when the cans were made was relatively evaluated by the marks ○ to ×. The evaluation of necking workability, flange workability, and seaming workability was 100, respectively.
The occurrence of cracks when formed into cans was relatively evaluated by the marks ○ to ×.

[0039]

[Table 1]

[0040]

[Table 2]

[0041]

[Table 3]

As is clear from Table 3, alloys A and B within the compositional range of the present invention were manufactured under the process conditions specified in the present invention. 1, No. 4, no. 7
In the case of, the Al-Mn-based intermetallic compound has a high alpha conversion rate,
Disperses strain during necking and flange processing.
Since there are many fine intermetallic compounds having a size of 5 to 2 μm, all the moldability required as a can body material was sufficiently satisfied. On the other hand, even if the component composition was within the range specified in the present invention, the temperature rising rate at 450 to 500 ° C. during the homogenization treatment was too high. In the case of 2, the α-formation rate was low and the fine particles were small, so that the flange formability and the seaming formability were inferior. In addition, the intermediate holding temperature during homogenization was too high.
In the case of No. 3, the α-formation rate was sufficient, but the fine particles were small, so that the flange formability was somewhat inferior. Furthermore, the intermediate holding temperature during homogenization was too low. In the case of 5, the α-formation ratio was low and the fine particles were small, so that the flange formability and the seaming formability were inferior. Furthermore, the homogenization temperature itself is low. In the case of 6, sufficient homogenization cannot be obtained,
Furthermore, since the α-formation ratio and the fine particles are low, DI moldability was also poor, and flange formability was significantly reduced.

On the other hand, as for the composition No. 1 using the alloy C whose Fe / Si ratio is higher than the upper limit specified in the present invention.
8, No. In the case of 9, even if appropriate homogenization treatment is performed, α
Since the conversion rate is low and there are few fine particles, flange formability,
The seaming workability was poor. In addition, No. In the case of 10, the Fe / Si ratio is 2 or less and the α-conversion rate can be increased to allow a sufficient amount of fine particles to exist by performing an appropriate homogenization treatment. Because of the formation of coarse intermetallic compounds, the breaking of the can during DI molding was remarkable, and the breaking was severe even in the steps after the necking process.

From the results of the above Examples and Comparative Examples, in order to obtain excellent formability of the can edge portion of the can after DI processing while ensuring high strength and excellent DI formability, the alloy composition By appropriately adjusting the homogenization treatment conditions in the manufacturing process, in particular, the heating rate of the homogenization treatment or the intermediate holding conditions in the heating process.
It is clear that it is important to optimize the α-ratio of the 1-Mn-based intermetallic compound and the size and distribution of the intermetallic compound particles on the plate surface.

[0045]

According to the present invention, by appropriately adjusting the component composition of the material alloy and appropriately selecting the homogenization treatment condition, the α-conversion rate of the Al-Mn-based intermetallic compound is 30% or more. By setting the distribution density of the intermetallic compound of 0.5 to 2 μm on the surface of the final plate to 10000 pieces / mm ² or more, not only the strength and the DI processability are excellent, but also the can body edge portion after the DI process is processed. It is possible to obtain a DI can body having excellent formability, that is, formability in necking, flanging, seaming, and the like. Therefore, according to the aluminum alloy plate for a DI can body of the present invention, it is possible to effectively prevent the occurrence of molding defects such as breakage of the can end due to work hardening in necking processing, flange processing, and seaming processing, and to reduce the processing load. do it,
It is possible to effectively prevent buckling of the can body during these processes, and to further reduce the weight of the can by reducing the diameter of the can body neck and the can lid. It becomes possible.

Claims (3)

[Claims] 1. Mg 0.5 to 1.8% (weight%, the same applies hereinafter), Mn 0.5 to 1.8%, Fe 0.3 to 0.8%,
Si 0.15 to 0.8% is contained, and the Fe / Si ratio is within the range of 2 or less, and 0.005 to 0.20% Ti alone or 0 as an ingot structure refiner. ．
Included in combination with 0001-0.05% B, balance A
1 and unavoidable impurities, the Al-Mn-based intermetallic compound has an α-formation ratio of 30% or more, and has a .0.
10000 intermetallic compounds / m within the range of 5 to 2 μm
An aluminum alloy plate for a DI can body, characterized in that it is present in an amount of m ² or more. 2. Mg 0.5-1.8%, Mn 0.5-
1.8%, Fe 0.3 to 0.8%, Si 0.15 to 0.
8%, Fe / Si ratio is within the range of 2 or less, and 0.005 to 0.
20% Ti alone or 0.0001-0.05
% B in combination with Cu 0.05-
0.5%, Cr 0.05 to 0.3%, Zn 0.1 to 0.
1% or more of 5%, the balance consisting of Al and unavoidable impurities, and the Al-Mn-based intermetallic compound having a α-conversion rate of 30% or more and a plate surface in the range of 0.5 to 2 μm An aluminum alloy plate for a DI can body, characterized in that the intermetallic compounds therein are present in an amount of 10,000 or more per mm ² . 3. Mg 0.5-1.8%, Mn 0.5-
1.8%, Fe 0.3 to 0.8%, Si 0.15 to 0.
8%, Fe / Si ratio is within the range of 2 or less, and 0.005 to 0.
20% Ti alone or 0.0001-0.05
% B in combination and, if necessary, Cu0.0
5 to 0.5%, Cr 0.05 to 0.3%, Zn 0.1
After casting an alloy containing one or more of 0.5% and the balance Al and unavoidable impurities, 530-6
In performing the homogenizing treatment at 10 ° C for 2 to 24 hours, the temperature range of 450 to 500 ° C in the temperature rising process is 70 ° C.
Of the Al-Mn-based intermetallic compound by continuously raising the temperature at a heating rate of / hr or less or maintaining the temperature within the temperature range for 0.5 to 2 hours, and performing hot rolling and cold rolling after the homogenization treatment. Alpha conversion rate of 30% or more and 0.5 on the plate surface
10000 intermetallic compounds / mm within the range of 2 μm / mm
^A method for producing an aluminum alloy sheet for a DI can body, which comprises obtaining ^two or more rolled sheets.