JP4060460B2 - Method for producing aluminum alloy plate for can body - Google Patents
Method for producing aluminum alloy plate for can body Download PDFInfo
- Publication number
- JP4060460B2 JP4060460B2 JP27237198A JP27237198A JP4060460B2 JP 4060460 B2 JP4060460 B2 JP 4060460B2 JP 27237198 A JP27237198 A JP 27237198A JP 27237198 A JP27237198 A JP 27237198A JP 4060460 B2 JP4060460 B2 JP 4060460B2
- Authority
- JP
- Japan
- Prior art keywords
- finish rolling
- rolling
- hot
- less
- hot finish
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Metal Rolling (AREA)
Description
【０００１】
【発明の属する技術分野】
本発明はＳｉの多いＢＲ屑（ブレージングシートなどの屑）を使用し、かつ熱間仕上圧延後のＣＡＬ焼鈍を省略した低コストの缶胴（キャンボディ）用アルミニウム合金板の製造方法に関する。
【０００２】
【従来の技術】
２ピースＤＩ缶の缶胴用合金板には、従来より、絞り、しごき、フランジ（蓋巻締め部）の各成形性に優れるＪＩＳ３００４合金(Si0.3,Fe0.7,Cu0.25,Mn1.0 〜1.5, Mg0.8〜1.3,Zn0.25wt%)やＪＩＳ３１０４合金などが用いられている。
前記缶胴用合金板は、前記合金鋳塊に、均質化処理、熱間圧延、ＣＡＬ焼鈍、冷間圧延を施して製造されている（特開昭61-288055 号公報参照）。
近年、コスト低減、生産性向上を目的に、原料の一部にＢＲ屑を使用し、かつＣＡＬ焼鈍を省略する製造方法（特開平6-2090号公報）が提案されている。
【０００３】
【発明が解決しようとする課題】
しかし、ＪＩＳ３００４合金にＢＲ屑を配合した原料を使用し、かつＣＡＬ焼鈍を省略して製造したものは、しごき成形性は向上するが、強度、耐食性、および耳率が悪化するという問題がある。
これはＢＲ屑にはＳｉが多く含まれるため熱間圧延後Ｍｇ2 Ｓｉが析出し易くなり、この析出物はＣＡＬ焼鈍を行わないため固溶せず、その結果強度および耐食性が低下し、また再結晶率が低くなり耳率が高くなるのである。
このようなことから、本発明者等は、ＪＩＳ３００４合金にＢＲ屑を配合して得た鋳塊を用いて熱間圧延後におけるＭｇ2 Ｓｉの析出挙動を調査した。その結果、圧延上がり温度を高くし、その後急速冷却することによりＭｇ2 Ｓｉは析出が十分抑制されることを知見し、さらに研究を進めて本発明を完成させるに至った。
本発明は、ＢＲ屑を使用し、かつ熱間仕上圧延後のＣＡＬ焼鈍を省略した低コストの缶胴用アルミニウム合金板の製造方法に関する。
【０００４】
【課題を解決するための手段】
請求項１記載の発明は、Ｓｉを０．３wt％超え０．５wt％以下、Ｆｅを０．３〜０．７wt％、Ｃｕを０．０５〜０．５wt％、Ｍｎを０．８〜１．４wt％、Ｍｇを０．８〜１．４wt％、Ｚｎを０．０５〜１．０wt％、Ｔｉを０．０１〜０．１wt％含有し、残部がＡｌおよび不可避不純物からなるＡｌ合金鋳塊に均質化処理、粗圧延と仕上圧延からなる熱間圧延、冷間仕上圧延を順に施す缶胴用Ａｌ合金板の製造方法であって、前記熱間仕上圧延の終了温度Ｔを（２４０＋２００ｓ（ｓ：Ｓｉのwt％））℃以上３７０℃以下とし、熱間仕上圧延終了後１００℃以下までを、熱間仕上圧延後巻き取ったコイルをファンで冷却することにより１０℃／ｈｒ以上の冷却速度で冷却した際に得られる熱間仕上圧延後のＡｌ合金板における直径０．１〜１μｍのＭｇ2Ｓｉ析出物の個数を１００００個／ｍｍ2以下にすることを特徴とする缶胴用アルミニウム合金板の製造方法である。
また、請求項２記載の発明は、Ｓｉを０．３ wt ％超え０．５ wt ％以下、Ｆｅを０．３〜０．７ wt ％、Ｃｕを０．０５〜０．５ wt ％、Ｍｎを０．８〜１．４ wt ％、Ｍｇを０．８〜１．４ wt ％、Ｚｎを０．０５〜１．０ wt ％、Ｔｉを０．０１〜０．１ wt ％含有し、残部がＡｌおよび不可避不純物からなるＡｌ合金鋳塊に均質化処理、粗圧延と仕上圧延からなる熱間圧延、冷間仕上圧延を順に施し、その後仕上焼鈍を施す缶胴用Ａｌ合金板の製造方法であって、前記熱間仕上圧延の終了温度Ｔを（２４０＋２００ｓ（ｓ：Ｓｉの wt ％））℃以上３７０℃以下とし、熱間仕上圧延終了後１００℃以下までを、熱間仕上圧延後巻き取ったコイルをファンで冷却することにより１０℃／ｈｒ以上の冷却速度で冷却した際に得られる熱間仕上圧延後のＡｌ合金板における直径０．１〜１μｍのＭｇ 2 Ｓｉ析出物の個数を１００００個／ｍｍ 2 以下にすることを特徴とする缶胴用アルミニウム合金板の製造方法である。
【０００５】
請求項３記載の発明は、得られる熱間仕上圧延終了後１００℃以下まで冷却した板材の再結晶率が９０％以上であることを特徴とする請求項１又は請求項２のいずれか一項記載の缶胴用アルミニウム合金板の製造方法である。ここで、再結晶率は、Ｌ方向断面のバーカー法（観察倍率１００倍）により測定した再結晶率の５視野の平均値を用いて評価した結果である。
【０００６】
【発明の実施の形態】
以下に本発明のアルミニウム合金板の合金組成について説明する。
ＦｅとＭｎはＦｅ−Ｍｎ系化合物として析出して、しごき加工時の耐焼付性を向上させる。
ＦｅとＭｎの含有量をそれぞれ０．３〜０．７wt％および０．８〜１．４wt％に規定する理由は、下限未満ではいずれもその効果が十分に得られず、上限を超えるといずれも初晶巨大化合物が生成して成形性が著しく低下するためである。
【０００７】
ＳｉはＦｅ−Ｍｎ系化合物に取り込まれて、前記化合物をより硬い化合物に変態させてしごき加工時の耐焼付性を向上させ、また前記化合物を微細化してしごき成形性とフランジ成形性を向上させる。
この他、ＳｉはＡｌマトリックスに固溶して強度向上に寄与する。ＭｇとＣｕも同じようにして強度向上に寄与する。
Ｓｉ、Ｍｇ、Ｃｕの含有量を、それぞれ０．３wt％を超え０．５wt％以下、０．０５〜０．５wt％、０．８〜１．４wt％に規定する理由は、下限未満ではいずれもその効果が十分に得られず、上限を超えるといずれもしごき成形性やフランジ成形性が低下し、さらにＳｉとＭｇの一部は、熱間仕上圧延後にＭｇ2 Ｓｉとして析出するが、この析出量が多いと、ＳｉとＭｇの固溶量が減少して強度が低下し、またＭｇ2 Ｓｉを起点として孔食が起き易くなり、さらに熱間仕上圧延後の再結晶が阻害されて耳率が高くなるためである。
【０００８】
ＺｎはＡｌマトリックスに固溶して強度向上に寄与し、またＭｇ2 Ｓｉなどの晶出物や析出物を微細化して、前記晶出物や析出物を起点とする孔食の発生を抑える。Ｚｎの含有量を０．０５〜１．０wt％に規定する理由は、０．０５wt％未満ではその効果が十分に得られず、１．０wt％を超えると成形性が低下し、またＭｇＺｎ2 化合物が析出して孔食が起き易くなるためである。Ｚｎは０．２５wt％を超えて含有させると十分な強度が得られ望ましい。
【０００９】
Ｔｉは鋳塊の結晶粒を微細化して得られる合金板に筋状模様が発生するのを抑える。Ｔｉの含有量を０．０１〜０．１wt％に規定する理由は、０．０１wt％未満ではその効果が十分に得られず、０．１wt％を超えると初晶巨大化合物が生成して成形性が低下するためである。
Ｔｉの微細化効果はＢを複合添加することにより向上する。このため、必要に応じてＢを０．０００１〜０．０１wt％の範囲で添加する。
【００１０】
本発明の缶胴用Ａｌ合金板は、例えば、本発明規定組成の合金をＤＣ鋳造して鋳塊とし、この鋳塊に、均質化処理、熱間粗圧延、熱間仕上圧延、冷間圧延を施して製造される。冷間圧延後、必要に応じて仕上焼鈍が施される。
前記均質化処理では、晶出物が再固溶し固溶元素の濃度分布が均一化する。さらにこの均質化処理で、前記Ｆｅ−Ｍｎ系化合物にＳｉが作用して得られる合金板の耐焼付性が向上する。前記均質化処理は、その効果および生産性を考慮すると５８０〜６２０℃、４〜１２ｈｒの条件で施すのが望ましい。
【００１１】
本発明では、熱間仕上圧延の終了温度Ｔを、（２４０＋２００ｓ（ｓはＳｉのwt％））℃以上３７０℃以下に規定し、さらに熱間仕上圧延後の冷却速度を１０℃／ｈｒ以上に規定して、得られる缶胴用Ａｌ合金板における０．１〜１μｍ径のＭｇ2 Ｓｉ化合物を１００００個／ｍｍ2 以下にする。
このようにすると熱間仕上圧延終了時におけるＭｇ2 Ｓｉ化合物の粒子間平均距離が１０μｍ以上と大きくなり、再結晶駆動力を十分付与すれば、熱間仕上圧延後に再結晶率が９０％以上になり耳率が低くなる。
【００１２】
なお、本発明における熱間仕上圧延の終了温度とＳｉ含有量との関係は、図１に示すようにＡ（Si0.30wt%, 370℃）、Ｂ（Si0.30wt%, 300℃）、Ｃ（Si0.50wt%, 340℃）、Ｄ（Si0.50wt%, 370℃）の４点で囲われる斜線部分である。
【００１３】
本発明において、１０℃／ｈｒ以上の冷却速度は、熱間仕上圧延後巻取ったコイルをファンで冷却することにより得られる。１００℃／分以上の冷却速度は、例えば、コイルの巻き替えを途中で水冷しながら行うことにより達成される。
本発明において、前記１０℃／ｈｒ以上の冷却速度で１００℃以下まで冷却する理由は、冷却後の温度が１００℃を超えていると析出が起きるためである。
【００１４】
本発明では、冷間圧延により材料に適度な強度が付与される。
冷間圧延での圧延率が６０％未満では材料強度が不足し、９０％を超えると加工硬化しすぎて深絞り成形時の耳率が高くなり、また成形性も低下する。従って最終冷間圧延率は６０〜９０％が望ましい。
【００１５】
本発明では、最終冷間圧延後に必要に応じて仕上焼鈍を行って、Ａｌ合金板の伸びを適正にする。前記仕上焼鈍は、１２０℃以下、３時間以下の低温短時間で行って缶胴材として必要な特性が阻害されないようにするのが望ましい。
【００１６】
【実施例】
以下に本発明を実施例により詳細に説明する。
（実施例１）
表１に示す本発明規定組成のＡｌ合金鋳塊（厚さ５００ｍｍ）に６００℃で６時間の均質化処理を施し、次いで熱間で粗圧延と仕上圧延を連続して行って厚さ２．２ｍｍの熱延板とし、これをコイルに巻取った。
コイルは１００℃以下まで２０℃／ｈｒの冷却速度で冷却した。
次に前記熱延板を厚さ０．３ｍｍに冷間圧延（圧延率８６．４％）し、続いて１１５℃で２時間の仕上焼鈍を施して缶胴用Ａｌ合金板を製造した。
前記熱間仕上圧延の終了温度は種々に変化させた。
【００１７】
（比較例１）
表１、２に示す本発明規定外組成のＡｌ合金鋳塊に実施例１と同じ処理を施して缶胴用Ａｌ合金板を製造した。
【００１８】
実施例１および比較例１で得られた各々のＡｌ合金板について、耳率、引張強度、缶の成形性、耐食性を下記方法により調査した。結果を表３、４に示す。
耳率は前記Ａｌ合金板から直径５７ｍｍの円板を切出し、これを直径３３ｍｍ肩Ｒ２．５ｍｍのポンチを用いてクリアランス３０％で深絞りしたときの缶の高さに対する耳の平均高さの割合で表した。
引張強度は前記Ａｌ合金板を２００℃で２０分間加熱し（塗装焼付け条件）、加熱前後の引張強さ（ＴＳ）と０．２％耐力（ＹＳ）をＪＩＳＺ２２４１に準じて測定した。
缶の成形性は炭酸飲料用のＤＩ缶胴（内径６６ｍｍφ、側壁板厚１０３μｍ、側壁先端部板厚１６５μｍ、ネック部の内径５７ｍｍ、ネック部段数４段、フランジ幅２．２ｍｍ）を多数製缶し、破胴、表面性状、フランジ割れを測定して評価した。
Ｍｇ2 Ｓｉ化合物の大きさと個数は、ＴＥＭ観察し、サイズ・分布を画像処理装置で調べた。
耐食性は孔食発生の有無で評価した。すなわち缶側壁から２０×８０ｍｍ2 に切出した試験片を４０℃の〔１％クエン酸＋０．１％ＮａＣｌ〕溶液に１週間浸漬し、浸漬後の試験片表面を観察し、２０μｍ以上の深さの孔食の有無で評価した。
表３、４には熱間仕上圧延終了後１００℃以下まで冷却した板材のＬ方向断面の再結晶率を併記した。前記再結晶率はバーカー法（観察倍率１００倍）により５視野を測定したときの再結晶率の平均値である。
【００１９】
【表１】
【表２】
【表３】
【表４】
表３、４より明らかなように本発明例のNo.1は引張強度が高く、耳率が低く（２．５％以内）、缶の成形性が良好（破胴やフランジ割れがなく、缶表面状態良好）で孔食も発生しなかった。これは熱間仕上圧延後のＭｇ2 Ｓｉの析出量が少ないためである。
これに対し、比較例のNo.2はＳｉが少ないため、α相晶出物が少なくなって表面の固体潤滑性が悪化し成形時に焼付きが生じた。No.7はＭｎが少ないためやはり焼付きが生じた。No.3はＳｉが多くまた熱間仕上圧延温度が低かったため、熱間仕上圧延後Ｍｇ2 Ｓｉ析出物が多量に析出して再結晶率が９０％未満となり、耳率が高く強度が低下し、また孔食も発生した。No.4はＦｅが、No.6はＣｕが、No.8はＭｎが、No.10 はＭｇが、No.12 はＺｎが、 No.14はＴｉがそれぞれ多いためいずれも成形性が低下した。No.5はＣｕが、No.9はＭｇがそれぞれ少ないため強度が低下した。No.11 はＺｎが少ないため、No.12 はＺｎが多くＭｇＺｎ2 析出物が析出したため孔食が発生した。 No.13はＴｉが少ないため筋模様が発生した。
【００２４】
（実施例２）
表５に示す本発明規定組成の厚さ５００ｍｍのＡｌ合金鋳塊に６００℃で６時間の均質化処理を施したのち、熱間粗圧延と熱間仕上圧延を施し、その後、高速で冷却し、続いて常法により板厚０．３ｍｍまで最終冷間圧延（圧延率：86.4％）し、最後に１１５℃で２時間仕上焼鈍して缶胴用Ａｌ合金板を製造した。
【００２５】
（比較例２）
表５、６に示す本発明規定外組成の厚さ５００ｍｍのＡｌ合金鋳塊を用いた他は、実施例２と同じ方法により缶胴用Ａｌ合金板を製造した。
【００２６】
実施例２および比較例２で製造した各々の缶胴用Ａｌ合金板について、実施例１と同じ方法により種々特性を調査した。結果を表７、８に示す。
【００２７】
【表５】
【表６】
【表７】
【表８】
表７、８より明らかなように、本発明例の No.21〜26はいずれも成形性（破胴、缶表面性状、耐フランジ割れ性）に優れ、耳率が低く（２．５％以内）、強度も十分高かった。これは熱延後のＭｇ2 Ｓｉ化合物の数量が少なく、熱延後に再結晶率が９０％以上になったためである。
これに対し比較例の No.27〜29は熱間圧延終了後の冷却速度が遅くＭｇ2 Ｓｉ析出物が多量に析出したため、強度が低くなり、孔食も発生した。 No.30〜32は熱間仕上圧延終了温度が低いため、No.34,35はＳｉが多いため、いずれも熱間仕上圧延後の再結晶率が９０％未満になり耳率が高くなった。 No.33は熱間仕上圧延温度が高いため結晶粒が粗大化して成形性が低下した。
【００３２】
図２に、本発明における熱間仕上圧延終了温度と熱間仕上圧延終了後１００℃以下まで冷却した板材の再結晶率との関係を示す。図２に示すプロット番号は表７、８に示す合金番号である。
この図から明らかなように、Ｓｉ含有量が０．５wt％以下で熱間仕上圧延終了温度が（２４０＋２００ｓ（ｓはＳｉのwt％））℃以上のものはいずれも再結晶率が１００％になっている。Ｓｉ含有量が０．５wt％を超えるもの、或いは熱間仕上圧延終了温度が（２４０＋２００ｓ）℃未満のものは、いずれも再結晶率が９０％未満である。なお、熱間仕上圧延終了温度が３７０℃を超えるものは板の表面状態が悪化し結晶粒が粗大化して成形性が低下していた。
【００３３】
【発明の効果】
以上に述べたように、本発明によれば、高強度、低耳率で、しごき成形性、耐孔食性に優れる缶胴用Ａｌ合金板をＢＲ屑を用い、ＣＡＬ焼鈍を省略して、低コスト、高生産性で製造することができる。依って、工業上顕著な効果を奏する。
【図面の簡単な説明】
【図１】本発明における熱間仕上圧延の終了温度とＳｉ含有量との関係を示す図である。
【図２】熱間仕上圧延終了温度と熱間仕上圧延終了後１００℃以下まで冷却した板材の再結晶率との関係を示す図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a low-cost method for producing an aluminum alloy plate for a can body (can body) using BR scraps (scraps such as brazing sheets) rich in Si and omitting CAL annealing after hot finish rolling.
[0002]
[Prior art]
Conventionally, the alloy plate for can body of 2 piece DI can has JIS3004 alloy (Si0.3, Fe0.7, Cu0.25, Mn1.) Which is excellent in each formability of drawing, ironing, flange (clamping part of lid). 0 to 1.5, Mg 0.8 to 1.3, Zn 0.25 wt%) and JIS 3104 alloy are used.
The alloy plate for can body is manufactured by subjecting the alloy ingot to homogenization, hot rolling, CAL annealing, and cold rolling (see Japanese Patent Application Laid-Open No. 61-288055).
In recent years, for the purpose of cost reduction and productivity improvement, a manufacturing method (Japanese Patent Laid-Open No. 6-2090) that uses BR scrap as a part of the raw material and omits CAL annealing has been proposed.
[0003]
[Problems to be solved by the invention]
However, using a raw material in which BR scrap is blended with JIS3004 alloy and omitting CAL annealing improves the iron formability, but has a problem that strength, corrosion resistance, and ear rate deteriorate.
This is because BR scrap contains a large amount of Si, so Mg 2 Si is likely to precipitate after hot rolling, and this precipitate does not undergo CAL annealing, so it does not dissolve, resulting in a decrease in strength and corrosion resistance. The recrystallization rate is lowered and the ear rate is increased.
For these reasons, the present inventors investigated the precipitation behavior of Mg 2 Si after hot rolling using an ingot obtained by blending BR scrap with JIS3004 alloy. As a result, it was found that precipitation of Mg 2 Si was sufficiently suppressed by increasing the rolling finish temperature and then rapidly cooling, and further researched to complete the present invention.
The present invention relates to a method for producing a low-cost aluminum body plate for can bodies that uses BR scraps and omits CAL annealing after hot finish rolling.
[0004]
[Means for Solving the Problems]
According to the first aspect of the present invention, Si is more than 0.3 wt% and 0.5 wt% or less, Fe is 0.3 to 0.7 wt%, Cu is 0.05 to 0.5 wt%, and Mn is 0.8 to 1 Al alloy casting containing 4 wt%, Mg 0.8-1.4 wt%, Zn 0.05-1.0 wt%, Ti 0.01-0.1 wt%, the balance being Al and inevitable impurities A method for producing an Al alloy sheet for a can body, in which a lump is subjected to homogenization treatment, hot rolling consisting of rough rolling and finish rolling, and cold finish rolling in order, and an end temperature T of the hot finish rolling is set to (240 + 200 s ( s: wt% of Si)) C or higher and 370 ° C. or lower, and after finishing hot finish rolling up to 100 ° C. or lower , by cooling the coil wound after hot finish rolling with a fan, cooling at 10 ° C./hr or higher M diameter 0.1~1μm in Al alloy plate after the finish rolling between obtained heat upon cooling at a rate It is a manufacturing method of can bodies for aluminum alloy sheet, which comprises a number of 2 Si precipitates 10000 / mm 2 or less.
The invention according to claim 2 is characterized in that Si is 0.3 wt % and 0.5 wt % or less, Fe is 0.3 to 0.7 wt %, Cu is 0.05 to 0.5 wt %, Mn Containing 0.8 to 1.4 wt %, Mg 0.8 to 1.4 wt %, Zn 0.05 to 1.0 wt %, Ti 0.01 to 0.1 wt %, and the balance Is a method for producing an Al alloy plate for a can body, in which an Al alloy ingot made of Al and inevitable impurities is subjected to homogenization, hot rolling consisting of rough rolling and finish rolling, and cold finish rolling in order, followed by finish annealing. Then, the finish temperature T of the hot finish rolling is set to (240 + 200 s (s: wt % of Si )) ° C. or more and 370 ° C. or less, and after the finish of the hot finish rolling, up to 100 ° C. or less is taken up after the hot finish rolling. After the hot finish rolling obtained by cooling the coil with a fan at a cooling rate of 10 ° C./hr or more. It is a manufacturing method of can bodies for aluminum alloy sheet, which comprises a number of Mg 2 Si precipitates having a diameter of 0.1~1μm to 10000 / mm 2 or less at l alloy plate.
[0005]
According to a third aspect of the invention, any one of
[0006]
DETAILED DESCRIPTION OF THE INVENTION
The alloy composition of the aluminum alloy plate of the present invention will be described below.
Fe and Mn precipitate as Fe-Mn compounds and improve seizure resistance during ironing.
The reason for regulating the contents of Fe and Mn to 0.3 to 0.7 wt% and 0.8 to 1.4 wt%, respectively, is that the effect is not sufficiently obtained if the content is less than the lower limit, and if the content exceeds the upper limit, either This is because the primary crystal giant compound is formed and the moldability is remarkably lowered.
[0007]
Si is incorporated into the Fe-Mn compound, transforms the compound into a harder compound to improve the seizure resistance during ironing, and refines the compound to improve iron moldability and flange formability. .
In addition, Si contributes to improving the strength by dissolving in the Al matrix. Similarly, Mg and Cu contribute to strength improvement.
The reason for specifying the contents of Si, Mg, and Cu to be more than 0.3 wt% and 0.5 wt% or less, 0.05 to 0.5 wt%, and 0.8 to 1.4 wt%, respectively, is less than the lower limit. However, if the upper limit is exceeded, both iron formability and flange formability are reduced, and part of Si and Mg is precipitated as Mg 2 Si after hot finish rolling. When the amount of precipitation is large, the solid solution amount of Si and Mg decreases, the strength decreases, and pitting corrosion tends to occur starting from Mg 2 Si. Further, recrystallization after hot finish rolling is hindered. This is because the rate increases.
[0008]
Zn dissolves in the Al matrix and contributes to improving the strength, and crystallized substances and precipitates such as Mg 2 Si are refined to suppress the occurrence of pitting corrosion starting from the crystallized substances and precipitates. The reason why the Zn content is specified to be 0.05 to 1.0 wt% is that the effect cannot be sufficiently obtained if it is less than 0.05 wt%, and if it exceeds 1.0 wt%, the formability deteriorates, and MgZn 2 This is because the compound precipitates and pitting corrosion easily occurs. When Zn is contained in an amount exceeding 0.25 wt%, it is desirable that sufficient strength can be obtained.
[0009]
Ti suppresses the generation of streak patterns on the alloy plate obtained by refining the crystal grains of the ingot. The reason why the Ti content is specified to be 0.01 to 0.1 wt% is that the effect cannot be sufficiently obtained if it is less than 0.01 wt%, and if the content exceeds 0.1 wt%, a primary giant compound is formed and molded. This is because the property decreases.
The effect of refinement of Ti is improved by adding B in combination. For this reason, B is added in the range of 0.0001 to 0.01 wt% as necessary.
[0010]
The Al alloy plate for can bodies of the present invention is, for example, DC cast an alloy of the present invention composition into an ingot, and this ingot is homogenized, hot rough rolled, hot finish rolled, cold rolled It is manufactured by applying. After cold rolling, finish annealing is performed as necessary.
In the homogenization treatment, the crystallized product is re-dissolved and the concentration distribution of the solid solution element is uniformized. Furthermore, this homogenization treatment improves the seizure resistance of the alloy plate obtained by Si acting on the Fe—Mn compound. The homogenization treatment is desirably performed under conditions of 580 to 620 ° C. and 4 to 12 hours in view of the effect and productivity.
[0011]
In the present invention, the finish temperature T of hot finish rolling is defined as (240 + 200 s (s is wt% of Si)) ° C. or more and 370 ° C. or less, and the cooling rate after hot finish rolling is 10 ° C./hr or more. The amount of the Mg 2 Si compound having a diameter of 0.1 to 1 μm in the obtained Al alloy plate for a can body is 10000 / mm 2 or less.
If this is done, the average distance between particles of the Mg 2 Si compound at the end of hot finish rolling will be as large as 10 μm or more, and if sufficient recrystallization driving force is applied, the recrystallization rate will be 90% or more after hot finish rolling. The ear rate is low.
[0012]
The relationship between the finish temperature of hot finish rolling and the Si content in the present invention is shown in FIG. 1 as follows: A (Si 0.30 wt%, 370 ° C.), B (Si 0.30 wt%, 300 ° C.), C The shaded area is surrounded by four points (Si 0.50 wt%, 340 ° C.) and D (Si 0.50 wt%, 370 ° C.).
[0013]
In the present invention, a cooling rate of 10 ° C./hr or more can be obtained by cooling the coil wound after hot finish rolling with a fan. A cooling rate of 100 ° C./min or higher is achieved, for example, by performing coil rewinding while cooling with water.
In the present invention, the reason for cooling to 100 ° C. or less at the cooling rate of 10 ° C./hr or more is that precipitation occurs when the temperature after cooling exceeds 100 ° C.
[0014]
In the present invention, moderate strength is imparted to the material by cold rolling.
If the rolling rate in cold rolling is less than 60%, the material strength is insufficient, and if it exceeds 90%, it is too hard to work and the ear rate during deep drawing increases, and the formability also decreases. Therefore, the final cold rolling rate is preferably 60 to 90%.
[0015]
In the present invention, finish annealing is performed as necessary after the final cold rolling to make the elongation of the Al alloy plate appropriate. The finish annealing is desirably performed at a low temperature of 120 ° C. or less and 3 hours or less for a short time so that the necessary properties as a can body material are not hindered.
[0016]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples.
Example 1
The aluminum alloy ingot (thickness 500 mm) of the present invention composition shown in Table 1 is subjected to a homogenization treatment at 600 ° C. for 6 hours, followed by hot rough rolling and finish rolling continuously to obtain a thickness of 2. A 2 mm hot-rolled sheet was formed and wound on a coil.
The coil was cooled to 100 ° C. or lower at a cooling rate of 20 ° C./hr.
Next, the hot-rolled sheet was cold-rolled to a thickness of 0.3 mm (rolling rate: 86.4%), and subsequently subjected to finish annealing at 115 ° C. for 2 hours to produce an Al alloy sheet for can bodies.
The finishing temperature of the hot finish rolling was variously changed.
[0017]
(Comparative Example 1)
The same treatment as in Example 1 was applied to an Al alloy ingot having a composition outside the scope of the present invention shown in Tables 1 and 2 to produce an Al alloy plate for a can body.
[0018]
For each of the Al alloy plates obtained in Example 1 and Comparative Example 1, the ear rate, tensile strength, can moldability, and corrosion resistance were examined by the following methods. The results are shown in Tables 3 and 4.
Ear ratio is the ratio of the average height of the ear to the height of the can when a 57 mm diameter disc is cut from the Al alloy plate and deeply drawn with a clearance of 30 mm and a diameter of 30 mm using a punch with a shoulder of R2.5 mm. Expressed in
Tensile strength was measured by heating the Al alloy plate at 200 ° C. for 20 minutes (paint baking conditions), and measuring the tensile strength (TS) and 0.2% proof stress (YS) before and after heating in accordance with JISZ2241.
Cans can be made from a large number of DI can barrels for carbonated beverages (inner diameter 66 mmφ, side wall plate thickness 103 μm, side wall end plate thickness 165 μm, neck inner diameter 57 mm, neck step 4 steps, flange width 2.2 mm) Then, the fracture, surface properties and flange cracks were measured and evaluated.
The size and number of Mg 2 Si compounds were observed with a TEM, and the size and distribution were examined with an image processing apparatus.
Corrosion resistance was evaluated by the presence or absence of pitting corrosion. That is, a test piece cut to 20 × 80 mm 2 from the side wall of the can was immersed in a [1% citric acid + 0.1% NaCl] solution at 40 ° C. for 1 week, and the surface of the test piece after immersion was observed to a depth of 20 μm or more. The presence or absence of pitting corrosion was evaluated.
Tables 3 and 4 also show the recrystallization rate of the L-direction cross section of the plate material cooled to 100 ° C. or less after the hot finish rolling. The recrystallization rate is an average value of the recrystallization rate when five fields of view are measured by the Barker method (observation magnification: 100 times).
[0019]
[Table 1]
[Table 2]
[Table 3]
[Table 4]
As is apparent from Tables 3 and 4, No. 1 of the present invention has high tensile strength, low ear rate (within 2.5%), and good moldability of the can (no broken or flange cracks, can The surface condition was good) and no pitting corrosion occurred. This is because the amount of Mg 2 Si deposited after hot finish rolling is small.
On the other hand, since No. 2 of the comparative example contained less Si, the α-phase crystallized product was reduced, the surface solid lubricity was deteriorated, and seizure occurred during molding. No. 7 still had seizure because of less Mn. No. 3 had a lot of Si and the hot finish rolling temperature was low, so a lot of Mg 2 Si precipitates were precipitated after hot finish rolling, the recrystallization rate was less than 90%, the ear ratio was high and the strength was reduced. Also, pitting corrosion occurred. No.4 is Fe, No.6 is Cu, No.8 is Mn, No.10 is Mg, No.12 is Zn, and No.14 is Ti. did. No. 5 had less Cu and No. 9 had less Mg, so the strength decreased. Since No. 11 had a small amount of Zn, No. 12 had a large amount of Zn, and MgZn 2 precipitates were deposited, so pitting corrosion occurred. No. 13 had streaks due to low Ti.
[0024]
(Example 2)
The aluminum alloy ingot with a thickness of 500 mm according to the present invention shown in Table 5 was homogenized at 600 ° C. for 6 hours, then subjected to hot rough rolling and hot finish rolling, and then cooled at high speed. Subsequently, final cold rolling (rolling rate: 86.4%) to a sheet thickness of 0.3 mm was performed by a conventional method, and finally finish annealing was performed at 115 ° C. for 2 hours to produce an Al alloy sheet for a can body.
[0025]
(Comparative Example 2)
An aluminum alloy plate for a can body was produced in the same manner as in Example 2 except that an aluminum alloy ingot having a thickness of 500 mm and having a composition outside of the present invention shown in Tables 5 and 6 was used.
[0026]
Various characteristics of each of the can body Al alloy plates manufactured in Example 2 and Comparative Example 2 were examined by the same method as in Example 1. The results are shown in Tables 7 and 8.
[0027]
[Table 5]
[Table 6]
[Table 7]
[Table 8]
As is clear from Tables 7 and 8, Nos. 21 to 26 of the present invention examples are all excellent in moldability (destructive body, can surface properties, flange cracking resistance), and have a low ear rate (within 2.5%). ) The strength was high enough. This is because the quantity of Mg 2 Si compound after hot rolling is small, and the recrystallization rate becomes 90% or more after hot rolling.
On the other hand, Nos. 27 to 29 of the comparative examples had a low cooling rate after the hot rolling was completed and a large amount of Mg 2 Si precipitates were deposited, resulting in low strength and pitting corrosion. Since No. 30 to 32 have a low hot finish rolling end temperature, No. 34 and 35 have a large amount of Si, so the recrystallization rate after hot finish rolling was less than 90% and the ear rate was high. . In No. 33, the hot finish rolling temperature was high, so the crystal grains became coarse and the formability deteriorated.
[0032]
FIG. 2 shows the relationship between the hot finish rolling end temperature and the recrystallization rate of the plate cooled to 100 ° C. or lower after the hot finish rolling in the present invention. The plot numbers shown in FIG. 2 are the alloy numbers shown in Tables 7 and 8.
As is apparent from this figure, the recrystallization rate is 100% in any case where the Si content is 0.5 wt% or less and the hot finish rolling finish temperature is 240 ° C. or more (s is wt% of Si) ° C. It has become. In the case where the Si content exceeds 0.5 wt% or the hot finish rolling end temperature is less than (240 + 200 s) ° C., the recrystallization rate is less than 90%. In the case where the finish temperature of hot finish rolling exceeds 370 ° C., the surface condition of the plate deteriorates, the crystal grains become coarse, and the formability deteriorates.
[0033]
【The invention's effect】
As described above, according to the present invention, an Al alloy plate for a can body having high strength, low ear rate, and excellent ironing formability and pitting corrosion resistance is obtained by using BR scraps and omitting CAL annealing. It can be manufactured at low cost and high productivity. Therefore, there is an industrially significant effect.
[Brief description of the drawings]
FIG. 1 is a graph showing the relationship between the finish temperature of hot finish rolling and the Si content in the present invention.
FIG. 2 is a diagram showing the relationship between the hot finish rolling end temperature and the recrystallization rate of a plate cooled to 100 ° C. or less after the hot finish rolling.
Claims (3)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27237198A JP4060460B2 (en) | 1998-09-28 | 1998-09-28 | Method for producing aluminum alloy plate for can body |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27237198A JP4060460B2 (en) | 1998-09-28 | 1998-09-28 | Method for producing aluminum alloy plate for can body |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000096198A JP2000096198A (en) | 2000-04-04 |
| JP4060460B2 true JP4060460B2 (en) | 2008-03-12 |
Family
ID=17512966
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27237198A Expired - Fee Related JP4060460B2 (en) | 1998-09-28 | 1998-09-28 | Method for producing aluminum alloy plate for can body |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4060460B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005076041A (en) * | 2003-08-28 | 2005-03-24 | Furukawa Sky Kk | Manufacturing method of aluminum alloy hard plate for can body |
-
1998
- 1998-09-28 JP JP27237198A patent/JP4060460B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JP2000096198A (en) | 2000-04-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP4189954B2 (en) | Method for forming aluminum alloy with excellent bending properties | |
| JP4901757B2 (en) | Aluminum alloy plate and manufacturing method thereof | |
| JP2011202283A (en) | Aluminum alloy, aluminum alloy foil, container and method of preparing aluminum alloy foil | |
| JPH06503854A (en) | Aluminum alloy suitable for can manufacturing | |
| JP3590685B2 (en) | Manufacturing method of aluminum alloy sheet for automobile outer panel | |
| JP4211875B2 (en) | Aluminum alloy composition and production method thereof | |
| JPS626740B2 (en) | ||
| JP4257135B2 (en) | Aluminum alloy hard plate for can body | |
| JP6857535B2 (en) | High-strength aluminum alloy plate with excellent formability, bendability and dent resistance and its manufacturing method | |
| JP2004027253A (en) | Aluminum alloy sheet for forming and method of manufacturing the same | |
| JP2001262265A (en) | Hot rolling stock of high formability aluminum alloy sheet | |
| JP4060460B2 (en) | Method for producing aluminum alloy plate for can body | |
| JPH07166285A (en) | Hardened al alloy sheet by baking and production thereof | |
| JP3867569B2 (en) | Aluminum foil for containers and manufacturing method thereof | |
| JP4771726B2 (en) | Aluminum alloy plate for beverage can body and manufacturing method thereof | |
| JPH0138866B2 (en) | ||
| JP2001262261A (en) | Aluminum alloy plate for can body excellent in can bottom formability and method for producing the same | |
| JPS6254183B2 (en) | ||
| JP2006283113A (en) | Aluminum alloy plate for beverage can body and manufacturing method thereof | |
| JPH09256129A (en) | Method for manufacturing high-strength heat-treatable aluminum alloy plate for drawing | |
| JP4750392B2 (en) | Aluminum alloy plate for bottle-shaped cans | |
| JP2000001730A (en) | Aluminum alloy plate for can body and method for producing the same | |
| JP3587993B2 (en) | Manufacturing method of aluminum alloy sheet for deep drawing | |
| JP2891620B2 (en) | High strength aluminum alloy hard plate excellent in stress corrosion cracking resistance and method of manufacturing the same | |
| JP2613522B2 (en) | Aluminum alloy plate for stay tub |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A711 | Notification of change in applicant |
Free format text: JAPANESE INTERMEDIATE CODE: A712 Effective date: 20040202 |
|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050811 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20070906 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070918 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20071119 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20071218 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20071220 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20101228 Year of fee payment: 3 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20131228 Year of fee payment: 6 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| LAPS | Cancellation because of no payment of annual fees |