JPH0633205A - Manufacture of aluminum alloy sheet for packing - Google Patents

Abstract

PURPOSE:To provide the method for manufacturing an aluminum alloy sheet for packing used for the application requiring high strength and formability such as the barrel and cap of a beverage can. CONSTITUTION:In the ingot of an alloy contg., by weight, 0.5 to 1.5% Mn, 0.5 to 3.5% Mg, 0.05 to 0.5% Cu, 0.05 to 0.5% Si and 0.2 to 0.7% Fe, and the balance Al with inevitable impurities, its surface layer is chamfered by >=8mm, and it is subjected to homogenizing treatment and deposition treatment according to necessaity. It is subjected to hot rolling, is thereafter subjected to cold rolling according to necessity and is subsequently heated to 400 to 600 deg.C at >=100 deg.C/min heating rate. immediately after the heating or after being held for <=30sec, it is cooled to <=200 deg.C at >=10 deg.C/min cooling rate and is subjected to >=20% cold rolling. In this way, the maximum length of the secondary phase in the central layer of the rolled sheet is regulated to <30% of the sheet thickness after DI forming, and the area occupancy ratio of the secondary phase is regulated to >=2.5%.

Description

【発明の詳細な説明】Detailed Description of the Invention

【０００１】[0001]

【産業上の利用分野】本発明は包装用アルミニウム合金
板の製造方法に関するものであり、特に飲料缶の胴体あ
るいは蓋等の高い強度と成形性を必要とする用途に用い
る包装用アルミニウム合金板の製造方法に関するもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an aluminum alloy sheet for packaging, and more particularly to an aluminum alloy sheet for packaging used for applications requiring high strength and moldability such as a body or lid of a beverage can. The present invention relates to a manufacturing method.

【０００２】[0002]

【従来の技術とその課題】アルミニウム製ビール缶ある
いは一般飲料缶の胴材としてこれまでＡＡ３００４合金
が使用されている。一方缶の蓋材としてはＡＡ５０５２
あるいは５１８２合金を一般に使用している。ＡＡ３０
０４合金は本来高い加工度の冷間圧延によりある程度成
形性に優れかつ胴材として必要な強度を確保している。
さらにコストダウンを目的とした材料の薄肉化が進み、
これに対応して胴材に要求される強度が上がって来てい
る。強度向上のために特開昭５２−１０５５０９号公報
のようなＭｇ₂ Ｓｉの析出を利用したもの、あるいは特
開昭５７−１２０６４８号公報のようなＡｌ−Ｃｕ−Ｍ
ｇ系の析出物により析出硬化を付与したアルミニウム合
金板の製造方法が公知である。一方コストダウンの方法
として成形工程での不具合を低減することにより生産性
の向上を図ることも大きな課題となっている。このため
に特開昭５９−１５７２５１号のように金属間化合物の
サイズや占有率を規定することにより成形性の向上を図
っている。また資源のリサイクルが社会的に大きな関心
を集めており、リサイクルに必要なコストの低減も課題
となっている。2. Description of the Related Art AA3004 alloy has been used as a body material for aluminum beer cans and general beverage cans. On the other hand, as a lid material for cans, AA5052
Alternatively, 5182 alloy is commonly used. AA30
The 04 alloy originally has a certain degree of formability by cold rolling with a high workability and secures the strength required as a body material.
Further thinning of materials aimed at cost reduction,
Correspondingly, the strength required for the body material has been increasing. Those utilizing precipitation of Mg ₂ Si as disclosed in JP-A-52-105509 or Al-Cu-M as disclosed in JP-A-57-120648 for improving strength.
A method for producing an aluminum alloy plate having precipitation hardening imparted by a g-based precipitate is known. On the other hand, it is also a major issue to improve productivity by reducing defects in the molding process as a method of cost reduction. For this reason, the formability is improved by defining the size and occupation rate of the intermetallic compound as in JP-A-59-157251. In addition, the recycling of resources has been of great social interest, and the reduction of the cost required for recycling has become an issue.

【０００３】[0003]

【発明が解決しようとする課題】本発明は合金内の第２
相が成形性に及ぼす影響について詳しく検討することに
より、第２相の形状が成形割れ発生に大きく影響してい
ることを見いだし、この知見により悪影響を及ぼす形状
の第２相を効率的に除去する方法を開発することを目的
とするものである。The present invention provides a second alloy
By investigating the influence of the phase on the formability in detail, it was found that the shape of the second phase has a large influence on the occurrence of molding cracks, and this finding effectively removes the second phase of the shape which has a bad influence. It is intended to develop a method.

【０００４】[0004]

【課題を解決するための手段】上記目的を達成するため
に本発明者らは、Ｍｎ０．５〜１．５％、Ｍｇ０．５〜
３．５％、Ｃｕ０．０５〜０．５％、Ｓｉ０．０５〜
０．５％、Ｆｅ０．２〜０．７％を含み、残部Ａｌと不
可避的不純物とからなる合金鋳塊に対して表面層を８mm
以上面削し、均質化処理および必要に応じて析出処理を
施し、熱間圧延後、必要に応じて冷間圧延を施した後に
４００〜６００℃の温度に１００℃／分以上の加熱速度
で加熱し、加熱後直ちにまたは３０秒以内保持した後に
１０℃／分以上の冷却速度で２００℃以下に冷却し、２
０％以上の冷間圧延を行い、圧延板中央層における第２
相の最大長をＤＩ成形後の板厚の３０％未満の長さと
し、かつ該第２相の面積占有率を２．５％以上とするこ
とを特徴とする包装用アルミニウム合金板の製造方法を
開発したものである。In order to achieve the above object, the inventors of the present invention have Mn of 0.5 to 1.5% and Mg of 0.5 to 1.5%.
3.5%, Cu0.05-0.5%, Si0.05-
A surface layer of 8 mm for an alloy ingot containing 0.5% and 0.2 to 0.7% Fe and the balance Al and unavoidable impurities.
After chamfering, homogenizing treatment and, if necessary, precipitating treatment, hot rolling, and optionally cold rolling, and then 400 to 600 ° C. at a heating rate of 100 ° C./min or more. Immediately after heating or holding for 30 seconds or less, and then cooling to 200 ° C. or less at a cooling rate of 10 ° C./min or more, 2
The cold rolling of 0% or more is performed, and the second
A method for producing an aluminum alloy plate for packaging, wherein the maximum phase length is less than 30% of the plate thickness after DI molding, and the area occupancy rate of the second phase is 2.5% or more. It was developed.

【０００５】[0005]

【作用】まず本発明の合金組成について説明する。Ｍｎ
はＦｅおよびＳｉとともに金属間化合物を形成し、しご
き加工時のダイスへの焼き付きを防止するために必要な
元素である。この時Ｍｎ系の金属間化合物中にＳｉを含
有させることによりさらに焼き付き防止効果が向上す
る。一方固溶状態のＭｎは強度向上に寄与するが過剰に
固溶している場合には均質化処理後の熱延や熱処理によ
り微細な析出物を生じ、中間焼鈍時の再結晶を抑制し、
耳率を大きくする。０．５％未満では最適な製造条件で
製造しても焼き付き防止の作用が不足し、長時間におよ
ぶ成形には不向きとなる。また１．５％を超えると通常
の鋳造条件では巨大な化合物を形成し易くなり、後述す
る成形時の亀裂発生の起点となる大きな第２相となる可
能性が高い。ＦｅはＭｎ同様に焼き付き防止効果があ
る。０．２％未満の添加では焼き付き防止効果が期待さ
れず、また高価な純度の高いアルミニウム原料を必要と
するために工業上意味をなさない。一方、０．７％を超
える添加ではＭｎ元素と同様、巨大化合物の形成をもた
らす。ここで鋳造時の冷却速度が著しく速い連続鋳造法
等を行う場合には上記化合物の大きさを小さく抑えるこ
とが可能になるためＭｎ、Ｆｅの添加量をさらに２倍ま
で多くすることができる。これら元素を主要組成とする
第２相は耐焼き付き性の観点からその面積占有率が２．
５％未満ではその効果が期待できない。上記元素の添加
量を増し、面積占有率が大きくなると一般に個々の第２
相の大きさが増し、割れの起点を形成する。したがって
通常の鋳造では第２相の面積占有率は７％以下が望まし
い。ＭｇはＣｕと同様、主に固溶することにより本系合
金の強度を向上させる重要な元素である。また溶体化処
理および焼き入れにより過飽和の固溶状態とすることに
より缶成形後の塗装焼き付けにおける２００℃前後の熱
処理時にＭｇ₂ ＳｉあるいはＡｌ−Ｍｇ−Ｃｕ系析出物
を形成し、強度向上が付加される。Ｍｇ添加量が０．５
％未満では必要な強度を維持できず、３．５％を超える
とスコーリングが発生し、事実上ＤＩ加工が不可能とな
る。凝固速度の速い特別な鋳造方法を用いることによ
り、耐焼き付き性の高いＭｎ系の析出物の密度を上げる
ことで、さらにＭｇ添加量を４．５％まで増すことは可
能である。ＣｕはＭｇと同様の効果が期待できる。そし
て０．０５％未満では強度の向上効果が期待できず、
０．５％を超えると成形性を害するとともに耐食性の点
においても問題を生じる。Ｓｉはそれ自体の固溶硬化性
は低いが熱処理の初期段階において形成される微細化合
物が他の元素の析出物の核生成の場所となることによっ
て他の元素の析出を促進する。そのためＳｉ添加はＦ
ｅ、Ｍｎの固溶量を下げるとともに析出硬化をもたらす
Ａｌ−Ｍｇ−Ｃｕ系化合物（Ｓ相）の析出を促進する。
また、さらに多いＳｉの添加によりさらに微細なＡｌ−
Ｃｕ−Ｍｇ−Ｓｉ系化合物（Ａｌ₅ Ｃｕ₂ Ｍｇ₈ Ｓｉ₆
のＱ相の準安定相）を新たに生じる。これら析出物は強
度の向上に有効であるがＱ相はＳ相と比較してより微細
であり、成形性を著しく低下させる。そのためＱ相は成
形前に生じていないことが必要である。Ｓｉ添加量は
０．０５％未満では焼き付け塗装後の強度の増加が望め
ず、０．５％より多いとＱ相の析出を抑止しきれず成形
性を害する。First, the alloy composition of the present invention will be described. Mn
Is an element necessary to form an intermetallic compound with Fe and Si and prevent seizure on the die during ironing. At this time, the seizure prevention effect is further improved by including Si in the Mn-based intermetallic compound. On the other hand, Mn in the solid solution state contributes to the strength improvement, but when it is excessively solid-solved, fine precipitates are generated by hot rolling or heat treatment after the homogenization treatment, and recrystallization during intermediate annealing is suppressed,
Increase the ear rate. If it is less than 0.5%, the effect of preventing seizure is insufficient even if it is manufactured under the optimum manufacturing conditions, which makes it unsuitable for molding for a long time. On the other hand, if it exceeds 1.5%, a huge compound is likely to be formed under normal casting conditions, and there is a high possibility that a large second phase will be a starting point of crack generation during molding described later. Like Mn, Fe has the effect of preventing seizure. Addition of less than 0.2% is not expected to have an anti-seizure effect and requires no expensive and highly pure aluminum raw material, which makes no industrial sense. On the other hand, addition of more than 0.7% leads to formation of a giant compound, like the Mn element. Here, when performing a continuous casting method or the like in which the cooling rate during casting is remarkably high, the size of the above compound can be suppressed to a small value, so that the addition amounts of Mn and Fe can be further doubled. The second phase containing these elements as the main composition has an area occupation ratio of 2. from the viewpoint of seizure resistance.
If it is less than 5%, the effect cannot be expected. When the amount of addition of the above elements is increased to increase the area occupancy rate, it is generally necessary to increase the
The phase size increases and forms the origin of cracking. Therefore, in ordinary casting, the area occupancy of the second phase is preferably 7% or less. Similar to Cu, Mg is an important element that improves the strength of the present alloy by mainly forming a solid solution. In addition, by forming a supersaturated solid solution state by solution treatment and quenching, Mg ₂ Si or Al-Mg-Cu based precipitates are formed during heat treatment at around 200 ° C in coating baking after can forming, and strength improvement is added. To be done. Mg addition amount is 0.5
If it is less than%, the required strength cannot be maintained, and if it exceeds 3.5%, scoring occurs, making DI processing practically impossible. By using a special casting method with a fast solidification rate, it is possible to increase the density of Mn-based precipitates having high seizure resistance and further increase the Mg addition amount to 4.5%. Cu can be expected to have the same effect as Mg. And if less than 0.05%, the effect of improving strength cannot be expected,
If it exceeds 0.5%, the formability is impaired and a problem occurs in terms of corrosion resistance. Si has a low solid solution hardening property by itself, but promotes the precipitation of other elements by the fine compound formed in the initial stage of heat treatment serving as a site for nucleation of precipitates of other elements. Therefore, Si addition is F
e, The precipitation amount of the Al-Mg-Cu-based compound (S phase) that causes precipitation hardening is reduced while reducing the solid solution amount of e and Mn.
Also, by adding more Si, finer Al-
Cu-Mg-Si-based compound _{(Al 5 Cu 2 Mg 8 Si} 6
A new metastable phase of Q-phase). These precipitates are effective in improving the strength, but the Q phase is finer than the S phase and remarkably deteriorates the formability. Therefore, it is necessary that the Q phase does not occur before molding. If the amount of Si added is less than 0.05%, an increase in strength after baking coating cannot be expected, and if it is more than 0.5%, precipitation of the Q phase cannot be suppressed and formability is impaired.

【０００６】次に本発明の製造方法について説明する。
上記組成の鋳塊は冷却速度の変化により、生じる晶出物
の分布および相が異なる。表層部は鋳塊中心部と比較し
て凝固時の冷却速度が大きく、微細なセルを形成すると
ともに添加元素の強制的に固溶している量が多い。この
ため引き続き行う均質化処理における晶出物の球状化あ
るいは耳率に悪影響をもたらす強制固溶したＭｎやＦｅ
を析出させるための処理時間が工業上問題となるほどに
長く必要なことが分かった。したがってこの異質な相を
面削により削除することにより成形性および耳率を向上
できる。面削する量が片面５mm未満では上記問題が生
じ、５mm以上８mm未満では材料の表層部に割れの起点と
なる球状化が不十分の第２相が残存してしまい成形性を
害する。従って面削量は８mm以上とする。特に生産性を
重視する用途では成形時の不具合を極力抑えるために面
削量を１０mm以上とすることが望ましい。これら鋳塊に
均質化処理、必要に応じ析出処理を施した後、熱間圧延
を行う。冷間圧延を施す場合に、先だって耳率を低減
し、強度を確保するための焼鈍を行っても良い。これら
熱延板あるいは冷延板に中間の焼鈍を施す。加熱は耳率
の悪化あるいは強度の低下を避けるために１００℃／分
以上の加熱速度が必要となる。ここで本中間焼鈍は強度
の向上に寄与するＭｇ、Ｃｕ、Ｓｉを固溶状態とするた
めの処理であり、４００℃未満では固溶量が十分ではな
く、６００℃を超えあるいは保持時間が３０秒を超える
と結晶粒の粗大化が生じ、加工性が劣化する。ここで得
られた固溶量を室温においても維持するために冷却途中
における析出を極力押さえることが必要である。したが
って冷却速度が１０℃／分未満の場合あるいは２００℃
を超える温度で保持すると強度の低下あるいはＱ相の析
出により加工性が劣化する。最終の冷間圧延は強度を向
上させる働きとともに多段の加工が施される場合の後半
の加工性を向上させる。この効果を得るためには２０％
以上の加工度の冷間圧延を必要とする。圧延後必要に応
じて再結晶温度以下での焼鈍を施すことが可能である。
特に成形性の阻害因子であるＱ相の析出を抑えるために
急速加熱装置を用いた短時間の回復処理は後工程におけ
る加工性を阻害することなく初期工程における加工性を
向上させる効果がある。Next, the manufacturing method of the present invention will be described.
The ingot having the above composition differs in the distribution and phase of the crystallized product produced due to the change in the cooling rate. The surface layer portion has a higher cooling rate during solidification as compared with the central portion of the ingot, forms fine cells, and has a large amount of additive elements forcibly solid-dissolved. For this reason, forced solid solution of Mn and Fe, which adversely affects the spheroidization of the crystallized product or the ear rate in the subsequent homogenization treatment,
It was found that the processing time for precipitating is long enough to be an industrial problem. Therefore, by removing this foreign phase by chamfering, the formability and ear rate can be improved. If the amount of chamfering is less than 5 mm on one side, the above problem occurs. If the amount of chamfering is 5 mm or more and less than 8 mm, the second phase, which is the starting point of cracking and is insufficiently spheroidized, remains and impairs the formability. Therefore, the amount of chamfering should be 8 mm or more. Particularly in applications where productivity is important, it is desirable that the amount of chamfering be 10 mm or more in order to minimize defects during molding. After subjecting these ingots to homogenization treatment and, if necessary, precipitation treatment, hot rolling is performed. When cold rolling is performed, annealing may be performed in advance to reduce the ear ratio and ensure the strength. Intermediate annealing is applied to these hot rolled sheets or cold rolled sheets. Heating requires a heating rate of 100 ° C./min or more in order to avoid deterioration of ear ratio or reduction of strength. Here, this intermediate annealing is a treatment for bringing Mg, Cu, and Si, which contribute to the improvement of strength, into a solid solution state, and the solid solution amount is not sufficient when the temperature is lower than 400 ° C., and the temperature exceeds 600 ° C. or the holding time is 30 If it exceeds a second, the crystal grains become coarse and the workability deteriorates. In order to maintain the amount of solid solution obtained here even at room temperature, it is necessary to suppress precipitation during cooling as much as possible. Therefore, if the cooling rate is less than 10 ℃ / min or 200 ℃
If it is held at a temperature above 1, the workability deteriorates due to the decrease in strength or the precipitation of Q phase. The final cold rolling improves the strength and also improves the workability of the latter half when multi-step processing is performed. 20% to get this effect
Cold rolling with the above workability is required. After rolling, it is possible to anneal at a recrystallization temperature or lower as necessary.
In particular, a short-time recovery treatment using a rapid heating device for suppressing the precipitation of the Q phase, which is a factor inhibiting the formability, has the effect of improving the workability in the initial process without inhibiting the workability in the subsequent process.

【０００７】材料中の第２相は加工中の応力集中源とな
る。そのため一般にここを起点として亀裂が発生する。
第２相の大きさと亀裂発生の有無を検討した結果、加工
後の最も薄い部位（中央層）の板厚の３０％以上の大き
な長さを持つ第２相が存在するとその加工時に亀裂を生
じることが分かった。逆に長さがこれ未満の第２相につ
いては直接亀裂の原因とはならず、返って成形性の向上
に結び付く。なお応力集中の度合いは第２相の大きさの
他に形状が問題となるが、本発明で限定した所定量の面
削および通常の均質化処理により成形性に害のある鋭利
な形状の第２相は生じないためにここでは考慮する必要
はない。また第２相の面積占有率を２．５％以上とした
のは面積占有率は２．５％未満では、第２相による成形
性向上の効果が充分でないからである。The second phase in the material is the source of stress concentration during processing. Therefore, a crack generally occurs here as a starting point.
As a result of examining the size of the second phase and the occurrence of cracks, if a second phase having a large length of 30% or more of the plate thickness of the thinnest part (center layer) after processing is present, cracking occurs during the processing. I found out. On the contrary, the second phase having a length less than this does not directly cause a crack, but rather leads to an improvement in formability. Although the degree of stress concentration depends on the shape in addition to the size of the second phase, the shape of the sharp shape which is harmful to the formability due to the predetermined amount of chamfering and the usual homogenization treatment limited in the present invention. It does not need to be considered here because the two phases do not occur. The reason why the area occupancy of the second phase is 2.5% or more is that if the area occupancy is less than 2.5%, the effect of improving the formability by the second phase is not sufficient.

【０００８】[0008]

【実施例】次に実施例により本発明を更に詳細に説明す
る。表１に示す合金組成の５００mm厚の水冷鋳造鋳塊に
対して表２に示す面削量の面削を行い、６００℃で５時
間の均質化処理および５００℃で２時間の析出処理を施
した。No．５のみ６２０℃で２４時間の均質化処理を実
施した。これら実験材に熱間圧延、８０％の加工度の冷
間圧延を施した後、加熱速度２７０℃／分で４８０℃で
１０秒の中間焼鈍を行い１０００℃／分の冷却速度で１
７０℃以下に冷却した。その後６０％の冷間圧延により
厚さ０．３mmの板材とした後、２２０℃で１０秒の熱処
理を施した。これら試料に対して以下の組織観察、機械
的性能試験および各種成形における割れ発生率を測定し
た。ここで材料中の第２相の最大長さおよび面積占有率
の測定は光学顕微鏡と組み合わせた画像解析装置を用い
て一画素当たり０．４μｍ長さの条件において圧延板板
厚中央部の０．１７mm²の範囲を測定して得られた結果
を用いた。包装用材料は塗装を施すために焼き付け処理
（ベーキング処理）後の材料の耐力値が特に問題とな
る。そこで試料の機械的性能としてベーキング処理に対
応する２０５℃で１０分間の熱処理後の耐力値を測定し
た。耳率測定は３３mmφのパンチを用いて絞り比１．７
にて絞ったカップについて測定した。また成形性評価に
おいては、深絞り性は３３mmφのパンチで限界絞り比
（ＬＤＲ）を測定することにより評価した。評価基準は
ＬＤＲが２．０以上：優れる、１．８５以上２．０未
満：普通、１．６５以上１．８５未満：若干劣る、１．
６５未満：割れ多発とした。しごき性はＤＩ加工により
板厚減少率を６４％と一定にした（最終板厚１０８μ
ｍ）条件にて内容量が３５０mlの標準的な缶を１０００
缶連続成形し、この時の割れ発生缶数により評価した。
評価基準は割れ無し：優れる、１〜４缶割れ：普通、５
〜９缶割れ：若干劣る、１０缶以上割れ：割れ多発とし
た。張り出し性はエリクセン試験機により張り出し高さ
により評価した。評価基準は張り出し高さが５．５mm以
上：優れる、５mm以上５．５mm未満：普通、４．５mm以
上５mm未満：若干劣る、４．５mm未満：割れ多発とし
た。リベット成形性は１０００個の缶蓋成形を行い、リ
ベット部における割れの発生数により評価した。評価基
準は割れ無し：優れる、１〜４個割れ：普通、５〜９個
割れ：若干劣る、１０個以上割れ：割れ多発とした。表
２にはこれら試料の機械的性能（熱処理後の耐力値）、
耳率、金属組織観察結果および成形試験結果を示す。The present invention will be described in more detail with reference to Examples. A 500 mm thick water-cooled casting ingot having the alloy composition shown in Table 1 was subjected to chamfering with the chamfering amount shown in Table 2, and subjected to homogenization treatment at 600 ° C. for 5 hours and precipitation treatment at 500 ° C. for 2 hours. did. No. Only No. 5 was homogenized at 620 ° C. for 24 hours. After hot rolling and cold rolling with a workability of 80%, these experimental materials were subjected to intermediate annealing at 480 ° C. for 10 seconds at a heating rate of 270 ° C./min and at a cooling rate of 1000 ° C./min for 1 second.
It was cooled to 70 ° C or lower. After that, a plate material having a thickness of 0.3 mm was cold-rolled by 60% and then heat-treated at 220 ° C. for 10 seconds. The following microstructure observations, mechanical performance tests, and cracking rates in various moldings were measured for these samples. Here, the maximum length and area occupancy of the second phase in the material were measured by using an image analyzer combined with an optical microscope under the condition of 0.4 μm length per pixel at the center of the rolled plate thickness of 0. The result obtained by measuring the range of 17 mm ² was used. Since the packaging material is coated, the yield strength value of the material after baking (baking) becomes a particular problem. Therefore, as the mechanical performance of the sample, the proof stress value after the heat treatment for 10 minutes at 205 ° C. corresponding to the baking treatment was measured. The ear ratio was measured using a 33 mmφ punch with a draw ratio of 1.7.
The measurement was performed on the cup squeezed at. Further, in the evaluation of formability, the deep drawability was evaluated by measuring the limit draw ratio (LDR) with a 33 mmφ punch. The evaluation criteria are LDR of 2.0 or more: excellent, 1.85 or more and less than 2.0: normal, 1.65 or more and less than 1.85: slightly inferior, 1.
Less than 65: Many cracks occurred. The ironing property was kept constant at a plate thickness reduction rate of 64% by DI processing (final plate thickness 108μ
Under standard conditions, 1000 standard cans with a capacity of 350 ml
Cans were continuously molded and evaluated by the number of cans in which cracking occurred.
The evaluation standard is no crack: excellent, 1 to 4 can cracks: normal, 5
~ 9 cans cracked: slightly inferior, 10 cans or more cracked: cracked frequently. The overhang property was evaluated by the overhang height using an Erichsen tester. The evaluation criteria were that the overhang height was 5.5 mm or more: excellent, 5 mm or more and less than 5.5 mm: normal, 4.5 mm or more and less than 5 mm: slightly inferior, less than 4.5 mm: frequent cracking. The rivet formability was evaluated by forming 1000 can lids and measuring the number of cracks in the rivet portion. The evaluation criteria were no cracks: excellent, 1 to 4 cracks: normal, 5 to 9 cracks: slightly inferior, 10 cracks or more: frequent cracking. Table 2 shows the mechanical performance (proof stress value after heat treatment) of these samples.
The ear rate, the metallographic structure observation result, and the molding test result are shown.

【０００９】[0009]

【表１】 [Table 1]

【００１０】[0010]

【表２】 [Table 2]

【００１１】表２から明らかなように本発明法による本
発明材No．１〜２は耐力値が高く、機械的性能に優れ、
耳率も低くまた各種成形性に優れている。これに対し、
合金組成、面削量のいずれかが本発明の範囲を外れる比
較品No．３〜５は成形性が劣っていることが判る。As is clear from Table 2, the material No. of the present invention according to the method of the present invention. 1-2 has a high proof stress value and excellent mechanical performance,
It has a low ear rate and various moldability. In contrast,
Comparative product No. 1 in which either the alloy composition or the amount of chamfering is outside the range of the present invention. It can be seen that 3 to 5 are inferior in moldability.

【００１２】[0012]

【発明の効果】以上述べたように本発明方法により得ら
れた包装用アルミニウム合金板は高い機械的強度ととも
に成形性に優れる。そのため本材料を使用することによ
り成形体の重量の低減や生産性が向上するとともに、最
近の厳しい成形条件、コストの低減の要請に対応するこ
とが可能となり、工業上顕著な効果を奏するものであ
る。As described above, the aluminum alloy sheet for packaging obtained by the method of the present invention has high mechanical strength and excellent formability. Therefore, by using this material, it is possible to reduce the weight of the molded product and improve the productivity, and it is possible to meet the recent severe demands for molding conditions and cost reduction, which is a significant industrial effect. is there.

Claims (4)

【特許請求の範囲】[Claims] 【請求項１】 Ｍｎ０．５〜１．５％（重量％以下同
じ）、Ｍｇ０．５〜３．５％、Ｃｕ０．０５〜０．５
％、Ｓｉ０．０５〜０．５％、Ｆｅ０．２〜０．７％を
含み、残部Ａｌと不可避的不純物とからなる合金鋳塊に
対して表面層を８mm以上面削し、均質化処理を施し、熱
間圧延した後に４００〜６００℃の温度に１００℃／分
以上の加熱速度で加熱し、加熱後直ちにまたは３０秒以
内保持した後に１０℃／分以上の冷却速度で２００℃以
下に冷却し、２０％以上の冷間圧延を行い、圧延板中央
層における第２相の最大長をＤＩ成形後の板厚の３０％
未満の長さとし、かつ該第２相の面積占有率を２．５％
以上とすることを特徴とする包装用アルミニウム合金板
の製造方法。1. Mn 0.5-1.5% (weight% or less same), Mg 0.5-3.5%, Cu 0.05-0.5
%, Si 0.05 to 0.5%, Fe 0.2 to 0.7%, and the surface layer is chamfered by 8 mm or more with respect to an alloy ingot composed of the balance Al and unavoidable impurities and homogenized. After being applied and hot-rolled, it is heated to a temperature of 400 to 600 ° C at a heating rate of 100 ° C / min or more, and immediately after heating or for 30 seconds or less, cooled to 200 ° C or less at a cooling rate of 10 ° C / min or more. Then, 20% or more of cold rolling is performed, and the maximum length of the second phase in the rolled plate central layer is 30% of the plate thickness after DI forming.
And the area occupancy of the second phase is 2.5%.
A method for manufacturing an aluminum alloy plate for packaging, characterized by the above. 【請求項２】 Ｍｎ０．５〜１．５％、Ｍｇ０．５〜
３．５％、Ｃｕ０．０５〜０．５％、Ｓｉ０．０５〜
０．５％、Ｆｅ０．２〜０．７％を含み、残部Ａｌと不
可避的不純物とからなる合金鋳塊に対して表面層を８mm
以上面削し、均質化処理を施し、熱間圧延後、冷間圧延
を施した後に４００〜６００℃の温度に１００℃／分以
上の加熱速度で加熱し、加熱後直ちにまたは３０秒以内
保持した後に１０℃／分以上の冷却速度で２００℃以下
に冷却し、２０％以上の冷間圧延を行い、圧延板中央層
における第２相の最大長をＤＩ成形後の板厚の３０％未
満の長さとし、かつ該第２相の面積占有率を２．５％以
上とすることを特徴とする包装用アルミニウム合金板の
製造方法。2. Mn 0.5 to 1.5%, Mg 0.5 to
3.5%, Cu0.05-0.5%, Si0.05-
A surface layer of 8 mm for an alloy ingot containing 0.5% and 0.2 to 0.7% Fe and the balance Al and unavoidable impurities.
Chamfering, homogenizing treatment, hot rolling, cold rolling, heating to a temperature of 400 to 600 ° C. at a heating rate of 100 ° C./min or more, and holding immediately or within 30 seconds after heating After that, it is cooled to 200 ° C. or lower at a cooling rate of 10 ° C./min or more and cold-rolled by 20% or more, and the maximum length of the second phase in the rolled plate central layer is less than 30% of the plate thickness after DI molding. And the area occupancy of the second phase is 2.5% or more. 【請求項３】 Ｍｎ０．５〜１．５％、Ｍｇ０．５〜
３．５％、Ｃｕ０．０５〜０．５％、Ｓｉ０．０５〜
０．５％、Ｆｅ０．２〜０．７％を含み、残部Ａｌと不
可避的不純物とからなる合金鋳塊に対して表面層を８mm
以上面削し、均質化処理および析出処理を施し、熱間圧
延した後に４００〜６００℃の温度に１００℃／分以上
の加熱速度で加熱し、加熱後直ちにまたは３０秒以内保
持した後に１０℃／分以上の冷却速度で２００℃以下に
冷却し、２０％以上の冷間圧延を行い、圧延板中央層に
おける第２相の最大長をＤＩ成形後の板厚の３０％未満
の長さとし、かつ該第２相の面積占有率を２．５％以上
とすることを特徴とする包装用アルミニウム合金板の製
造方法。3. Mn 0.5-1.5%, Mg 0.5-
3.5%, Cu0.05-0.5%, Si0.05-
A surface layer of 8 mm for an alloy ingot containing 0.5% and 0.2 to 0.7% Fe and the balance Al and unavoidable impurities.
After chamfering, homogenizing treatment and precipitation treatment, hot rolling, and then heating at a temperature of 400 to 600 ° C. at a heating rate of 100 ° C./min or more, and immediately after heating or after holding for 30 seconds, 10 ° C. Cooling to 200 ° C. or less at a cooling rate of / min or more, cold rolling of 20% or more, and setting the maximum length of the second phase in the rolled plate central layer to a length of less than 30% of the plate thickness after DI molding, And the manufacturing method of the aluminum alloy plate for packaging characterized by making the area occupancy rate of this 2nd phase 2.5% or more. 【請求項４】 Ｍｎ０．５〜１．５％、Ｍｇ０．５〜
３．５％、Ｃｕ０．０５〜０．５％、Ｓｉ０．０５〜
０．５％、Ｆｅ０．２〜０．７％を含み、残部Ａｌと不
可避的不純物とからなる合金鋳塊に対して表面層を８mm
以上面削し、均質化処理および析出処理を施し、熱間圧
延後、冷間圧延を施した後に４００〜６００℃の温度に
１００℃／分以上の加熱速度で加熱し、加熱後直ちにま
たは３０秒未満保持した後に１０℃／分以上の冷却速度
で２００℃以下に冷却し、２０％以上の冷間圧延を行
い、圧延板中央層における第２相の最大長をＤＩ成形後
の板厚の３０％未満の長さとし、かつ該第２相の面積占
有率を２．５％以上とすることを特徴とする包装用アル
ミニウム合金板の製造方法。4. Mn 0.5 to 1.5%, Mg 0.5 to
3.5%, Cu0.05-0.5%, Si0.05-
A surface layer of 8 mm for an alloy ingot containing 0.5% and 0.2 to 0.7% Fe and the balance Al and unavoidable impurities.
Chamfering, homogenization treatment and precipitation treatment, hot rolling, cold rolling, and heating at a heating rate of 100 ° C./min or more at a temperature of 400 to 600 ° C. immediately or after heating 30 After being held for less than a second, it is cooled to 200 ° C. or less at a cooling rate of 10 ° C./min or more and cold-rolled at 20% or more, and the maximum length of the second phase in the center layer of the rolled plate is set to A method for producing an aluminum alloy sheet for packaging, which has a length of less than 30% and an area occupancy of the second phase of 2.5% or more.