JPH1112676A - Hard aluminum alloy sheet for forming, can lid using the hard sheet, and production of the hard sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hard Al alloy sheet for forming, excellent in local bulge formability, etc., and its production. SOLUTION: This hard Al alloy sheet for forming is obtained by applying baking finishing to a hard sheet of an Al alloy having a composition consisting of, by weight, 3.0-5.0% Mg, 0.05-0.2% Cu, 0.2-0.7% Mn, <=0.3% (including 0%) Fe, <=0.1% (including 0%) Cr, 0.001-0.05% Ti, and the balance Al with inevitable impurities. The half-width of X-ray diffraction angle 2θ of (200) crystal plane of the hard Al alloy sheet after baking finish is regulated to <=0.16 deg, and >=50% of Cu content is allowed to enter into solid solution in the Al matrix. Because the rate of entering into solid solution of Cu is as high as >=50%, required strength can be obtained at low cold rolling rate and, accordingly, excellent local bulge formability can be provided. Further, because softening with the lapse of time is hardly brought about, can openability, pressure resistance, etc., can be superiorly maintained over a long period when this hard Al alloy sheet is used for a can lid, etc.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、リベット成形性な
どの局部的張出加工性に優れ、缶蓋などに用いたときの
開缶性や耐圧性が長期間良好に保持される成形用アルミ
ニウム合金硬質板、前記硬質板を用いた缶蓋、および前
記硬質板の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to aluminum for forming, which is excellent in local overhanging workability such as rivet forming property, and has good openability and pressure resistance for a long time when used for a can lid or the like. The present invention relates to an alloy hard plate, a can lid using the hard plate, and a method for manufacturing the hard plate.

【０００２】[0002]

【従来の技術】従来、飲料缶の缶蓋などに用いられる成
形用アルミニウム合金硬質板には、強度、成形性の観点
から、主に、ＪＩＳ−５０８２合金、ＪＩＳ−５１８２
合金などＭｇを４wt％以上含有するアルミニウム合金が
使用されている。また前記成形用アルミニウム合金硬質
板の製造は、アルミニウム合金鋳塊を均質化処理したの
ち、下記またはの方法により、０．４ｍｍ以下の厚
さの硬質板に加工し、この硬質板に、外的環境から保護
するため、２００〜３００℃で５〜３０秒の高温短時間
の焼付塗装（コイルコート）を施して行われる。前記
の方法は、均質化処理後の鋳塊を、厚さ３〜５ｍｍの板
材に熱間圧延し、この熱間圧延板に冷間圧延、中間焼鈍
（４５０〜５５０℃）、最終冷間圧延を施す方法であ
る。前記の方法は、均質化処理後の鋳塊を、厚さ２ｍ
ｍ程度の板材に熱間圧延し、この熱間圧延板に中間焼鈍
を施すか、または熱間圧延後そのまま最終冷間圧延を施
す方法である。この他、成形用アルミニウム合金硬質板
には、ディンプル加工やリベット成形のような局部的張
出加工性が良好なことが要求されている。しかし、前記
ＪＩＳ−５１８２合金などを用いた成形用アルミニウム
合金硬質板は、前記焼付塗装工程で強度が大幅に低下す
るため、前記最終冷間圧延率を大きくして焼付塗装前の
初期強度を高めておく必要がある。しかし、最終冷間圧
延率を大きくすると、ディンプル加工やリベット成形の
ような局部的張出加工性が悪化するという問題がある。
また成形用アルミニウム合金硬質板を、たとえば、缶蓋
に用いる場合は、缶蓋成形後、開缶性および耐圧性が経
時的に低下するという問題がある。開缶性が悪くなる
と、缶を開ける際スコア以外の部分が裂けることがあり
安全性に問題がある。また耐圧性が低下すると缶の内圧
により凹状エンドが凸状に反転してしまうことがある。2. Description of the Related Art Conventionally, aluminum alloy hard plates for molding used for can lids of beverage cans mainly include JIS-5082 alloy and JIS-5182 from the viewpoint of strength and formability.
Aluminum alloys containing 4 wt% or more of Mg, such as alloys, are used. The aluminum alloy hard plate for molding is manufactured by homogenizing an aluminum alloy ingot, then processing into a hard plate having a thickness of 0.4 mm or less by the following method, and applying an external In order to protect it from the environment, baking is performed at 200 to 300 [deg.] C. for 5 to 30 seconds at a high temperature for a short time (coil coating). In the above method, the ingot after the homogenization treatment is hot-rolled into a plate having a thickness of 3 to 5 mm, and the hot-rolled plate is subjected to cold rolling, intermediate annealing (450 to 550 ° C), and final cold rolling. It is a method of applying. According to the above method, the ingot after the homogenization treatment is processed to a thickness of 2 m.
This is a method in which hot rolling is performed on a sheet material of about m, and intermediate annealing is performed on the hot rolled sheet, or final cold rolling is performed as it is after hot rolling. In addition, the aluminum alloy hard plate for forming is required to have good local overhanging workability such as dimple forming and rivet forming. However, since the strength of the aluminum alloy hard plate for forming using the JIS-5182 alloy or the like is greatly reduced in the baking coating process, the final cold rolling ratio is increased to increase the initial strength before the baking coating. Need to be kept. However, when the final cold rolling reduction is increased, there is a problem that local stretchability such as dimple processing and rivet forming is deteriorated.
Further, when the aluminum alloy hard plate for molding is used for, for example, a can lid, there is a problem that the can openability and the pressure resistance decrease with time after the can lid is formed. If the openability of the can deteriorates, parts other than the score may be torn when the can is opened, and there is a problem in safety. Further, when the pressure resistance is reduced, the concave end may be inverted to a convex shape due to the internal pressure of the can.

【０００３】[0003]

【発明が解決しようとする課題】このようなことから、
特性を安定化させるために、最終冷間圧延後、安定化熱
処理を施す対策が取られており、このため生産性が著し
く低下するという問題があった。本発明者らは上記課題
を解決するため鋭意研究を行い、たとえば、前記の開缶
性や耐圧性の経時的低下は、加工組織の回復（転位密度
の低減）によること、この加工組織の回復は、Ｆｅの含
有量を規制し、またＣｕの固溶量を調整することにより
抑制できることを知見し、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、リベット成形性などの
局部的張出加工性に優れ、缶蓋などに用いたときの開缶
性や耐圧性が長期間良好に保持される成形用アルミニウ
ム合金硬質板、前記硬質板を用いた缶蓋、および前記硬
質板の製造方法の提供を目的とする。SUMMARY OF THE INVENTION
In order to stabilize the characteristics, measures have been taken to apply a stabilizing heat treatment after the final cold rolling, and there has been a problem that productivity is significantly reduced. The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems. For example, the time-dependent decrease in can openability and pressure resistance is due to the recovery of the processed structure (reduction in dislocation density). Has been found that it can be suppressed by regulating the content of Fe and adjusting the amount of solid solution of Cu, and further advanced the research to complete the present invention. The present invention provides an aluminum alloy hard plate for forming, which is excellent in local overhanging workability such as rivet formability, and has good openability and pressure resistance when used for a can lid or the like for a long time. And a method for manufacturing the hard plate.

【０００４】[0004]

【課題を解決するための手段】請求項１記載の発明は、
Ｍｇを３．０〜５．０wt％、Ｃｕを０．０５〜０．２wt
％、Ｍｎを０．２〜０．７wt％、Ｆｅを０．３wt％以下
（０wt％を含む）、Ｃｒを０．１wt％以下（０wt％を含
む）、Ｔｉを０．００１〜０．０５wt％含有し、残部が
アルミニウムと不可避不純物からなるアルミニウム合金
の硬質板に焼付塗装が施され、前記焼付塗装後のアルミ
ニウム合金硬質板の（２００) 結晶面のＸ線回折角２θ
の半価巾が０．１６度以下、Ｃｕの含有量の５０％以上
がアルミニウムマトリックスに固溶していることを特徴
とする成形用アルミニウム合金硬質板である。According to the first aspect of the present invention,
3.0 to 5.0 wt% Mg, 0.05 to 0.2 wt% Cu
%, Mn: 0.2 to 0.7 wt%, Fe: 0.3 wt% or less (including 0 wt%), Cr: 0.1 wt% or less (including 0 wt%), Ti: 0.001 to 0.05 wt% %, And the remainder is baked on an aluminum alloy hard plate consisting of aluminum and unavoidable impurities, and the X-ray diffraction angle 2θ of the (200) crystal plane of the baked aluminum alloy hard plate.
Is an aluminum alloy hard plate for forming, characterized in that the half width of the aluminum alloy is 0.16 degrees or less and 50% or more of the Cu content is dissolved in the aluminum matrix.

【０００５】請求項２記載の発明は、請求項１記載の成
形用アルミニウム合金硬質板が用いられていることを特
徴とする缶蓋である。According to a second aspect of the present invention, there is provided a can lid comprising the aluminum alloy hard plate for forming according to the first aspect.

【０００６】請求項３記載の発明は、Ｍｇを３．０〜
５．０wt％、Ｃｕを０．０５〜０．２wt％、Ｍｎを０．
２〜０．７wt％、Ｆｅを０．３wt％以下（０wt％を含
む）、Ｃｒを０．１wt％以下（０wt％を含む）、Ｔｉを
０．００１〜０．０５wt％含有し、残部がアルミニウム
と不可避不純物からなるアルミニウム合金を溶解鋳造し
て鋳塊とし、この鋳塊に、均質化処理、熱間圧延、冷間
圧延、中間焼鈍、最終冷間圧延、焼付塗装の各工程を順
に施すアルミニウム合金硬質板の製造方法において、前
記均質化処理を４５０〜５５０℃の温度範囲で１時間以
上加熱して施し、中間焼鈍を１０℃／秒以上の昇温速度
で加熱し、４００〜５４０℃の温度範囲で２分以内保持
したのち、２００℃までを１℃／秒以上の冷却速度で冷
却し、２００℃を過ぎてから１００℃までを５℃／秒以
上の冷却速度で冷却して施し、最終冷間圧延を５０％以
上８０％未満の圧延率で施し、焼付塗装を２００℃まで
を５℃／秒以上の昇温速度で加熱し、２００℃を超えて
から１℃／秒以上の昇温速度で３００℃以下の所定温度
まで加熱し、２００〜３００℃の所定温度に６０秒以内
保持したのち１０℃／秒以上の冷却速度で冷却して施す
ことを特徴とする請求項１記載の成形用アルミニウム合
金硬質板の製造方法である。According to a third aspect of the present invention, Mg is added to 3.0 to 3.0.
5.0 wt%, 0.05 to 0.2 wt% of Cu, and 0.1 wt% of Mn.
2 to 0.7 wt%, Fe 0.3 wt% or less (including 0 wt%), Cr 0.1 wt% or less (including 0 wt%), Ti 0.001 to 0.05 wt%, the balance being An aluminum alloy consisting of aluminum and unavoidable impurities is melt-cast to form an ingot, and the ingot is subjected to homogenization, hot rolling, cold rolling, intermediate annealing, final cold rolling, and baking coating in order. In the method for producing an aluminum alloy hard plate, the homogenization treatment is performed by heating at a temperature range of 450 to 550 ° C. for 1 hour or more, and the intermediate annealing is heated at a rate of 10 ° C./sec or more, and 400 to 540 ° C. After the temperature is maintained within 2 minutes within the range of 2 minutes, cooling to 200 ° C. is performed at a cooling rate of 1 ° C./second or more, and cooling from 200 ° C. to 100 ° C. is performed at a cooling rate of 5 ° C./second or more. , Final cold rolling at a rolling rate of 50% or more and less than 80% Then, the baking coating is heated up to 200 ° C. at a heating rate of 5 ° C./sec or more, and then heated to a predetermined temperature of 300 ° C. or less at a heating rate of 1 ° C./sec or more after exceeding 200 ° C. 2. The method according to claim 1, wherein the aluminum alloy hard plate is formed at a predetermined temperature of 300 [deg.] C. within 60 seconds and then cooled at a cooling rate of 10 [deg.] C./second or more.

【０００７】[0007]

【発明の実施の形態】以下に本発明の成形用アルミニウ
ム合金硬質板の合金成分について説明する。Ｍｇは基本
的合金元素で強度向上に寄与する。Ｍｇの含有量を３．
０〜５．０wt％に規定する理由は、Ｍｇが３．０wt％未
満では缶蓋などに要求される強度が十分に得られず、
５．０wt％を超えると局部的張出加工性などが低下し、
また熱延時に割れが生じ易くなり生産性が低下するため
である。BEST MODE FOR CARRYING OUT THE INVENTION The alloy components of an aluminum alloy hard plate for forming according to the present invention will be described below. Mg is a basic alloying element and contributes to strength improvement. Mg content is 3.
The reason for specifying 0 to 5.0 wt% is that if the Mg content is less than 3.0 wt%, the strength required for a can lid or the like cannot be sufficiently obtained.
If it exceeds 5.0% by weight, local overhanging workability and the like will decrease,
In addition, cracks are likely to occur during hot rolling and productivity is reduced.

【０００８】ＭｎはＭｇと同じように強度向上に寄与
し、さらにＡｌ−Ｆｅ−Ｍｎ系化合物を生成してスコア
部分の引裂き性を高める。その含有量を０．２〜０．７
wt％に規定する理由は、０．２wt％未満ではその効果が
十分に得られず、０．７wt％を超えるとＡｌ−Ｆｅ−Ｍ
ｎ系化合物が粗大化して、局部的張出加工性が低下する
ためである。[0008] Mn contributes to the improvement of strength in the same manner as Mg, and further forms an Al-Fe-Mn compound to enhance the tearability of the score portion. The content is 0.2-0.7
The reason why the content is specified as wt% is that if the content is less than 0.2 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.7 wt%, Al—Fe—M
This is because the n-type compound is coarsened and the local overhanging processability is reduced.

【０００９】Ｃｕは、その含有量（添加量）の一部がア
ルミマトリックスに固溶する。この固溶したＣｕは合金
の加工硬化能を高めて強度向上に寄与する。その含有量
（添加量）を０．０５〜０．２wt％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、０．
２wt％を超えると加工性および耐食性が低下するためで
ある。Part of the content (addition amount) of Cu forms a solid solution in the aluminum matrix. The solid solution Cu enhances the work hardening ability of the alloy and contributes to the improvement of the strength. The reason for defining the content (addition amount) to be 0.05 to 0.2 wt% is as follows.
If it is less than 0.05 wt%, the effect cannot be sufficiently obtained.
If the content exceeds 2% by weight, workability and corrosion resistance are reduced.

【００１０】本発明において、Ｃｕの固溶率をＣｕの含
有量（添加量）の５０％以上に規定する理由は、５０％
未満では、缶蓋などとして必要な強度を得るために最終
冷間圧延率を高めることになり、その結果、局部的張出
加工性が低下し、また加工組織の回復（合金の軟化）が
大きくなり、缶蓋などに用いたときに開缶性や耐圧性が
経時的に低下するためである。このように最終冷間圧延
率を下げると、耳率の低下、強度異方性の低下、曲げ加
工性の向上などの利点も得られる。In the present invention, the reason why the solid solution rate of Cu is specified to be 50% or more of the content (addition amount) of Cu is as follows.
If it is less than 1, the final cold rolling rate will be increased to obtain the necessary strength as a can lid, etc., resulting in a decrease in local stretch workability and a large recovery of the processed structure (softening of the alloy). This is because when used for a can lid or the like, the can opening property and the pressure resistance decrease over time. When the final cold rolling reduction is reduced in this way, advantages such as a reduction in ear ratio, a reduction in strength anisotropy, and an improvement in bending workability can be obtained.

【００１１】ところで、金属材料においては、特定の結
晶面のＸ線回折角２θの半価巾は、結晶格子間隔の乱れ
により変化し、加工率が大きい程、つまり転位密度が高
い程大きくなることが知られている。すなわち、転位密
度ρと半価巾ΔＳの間には、ΔＳ＝Ｋρ^1/2 （Ｋは定
数）の関係がある。本発明では、局部的張出加工性に優
れ、缶蓋などに用いたときの開缶性や耐圧性が長期に渡
り良好に保持されるための成形用アルミニウム合金硬質
板の適正な最終冷間圧延率を、前記半価巾を指標にして
制御するのである。本発明において、硬質板の（２０
０) 結晶面のＸ線回折角２θの半価巾を０．１６度以下
に規定する理由は、前記半価巾が０．１６度を超えるほ
どに転位密度が高くなると、局部的張出加工性が低下
し、また転位密度が高いことによる回復（軟化）の駆動
力が大きくなり、短期間のうちに開缶性や耐圧性などが
低下するためである。なお、前記半価巾は、Ｘ線を下記
条件で照射したときの値とする。 Ｘ線：ＣｕのＫα線（波長１．５４０５Å）、発散スリ
ット：１°、発光スリット：０．１５ｍｍ、散乱スリッ
ト：１°。 本発明において、前記半価巾の上限値である０．１６度
は、本発明者等が多くの実験を基にして明らかにしたも
のである。In a metallic material, the half-value width of the X-ray diffraction angle 2θ of a specific crystal plane changes due to the disorder of the crystal lattice spacing, and increases as the working rate increases, that is, as the dislocation density increases. It has been known. That is, there is a relationship of ΔS = Kρ ^1/2 (K is a constant) between the dislocation density ρ and the half width ΔS. In the present invention, the proper final cold work of the aluminum alloy hard plate for forming is excellent in local overhanging workability, and the can openability and pressure resistance when used for a can lid and the like are maintained well over a long period of time. The rolling reduction is controlled using the half width as an index. In the present invention, (20)
0) The reason why the half width of the X-ray diffraction angle 2θ of the crystal plane is defined to be 0.16 degrees or less is that if the dislocation density becomes higher as the half width exceeds 0.16 degrees, the local overhanging process is performed. This is because the driving force of the recovery (softening) due to the high dislocation density is increased, and the openability and pressure resistance are reduced within a short period of time. The half width is a value when X-rays are irradiated under the following conditions. X-ray: Cu Kα ray (wavelength 1.5405 °), divergence slit: 1 °, emission slit: 0.15 mm, scattering slit: 1 °. In the present invention, the upper limit of the half width, 0.16 degrees, has been clarified by the present inventors based on many experiments.

【００１２】ＦｅはＡｌ−Ｆｅ−Ｍｎ系晶出物を生成し
て開缶性を向上させる。また結晶粒を微細化して合金の
加工性を大幅に向上させる。その含有量を０．３wt％以
下に規定する理由は、０．３wt％を超えると、加工硬化
能を高めるＣｕの固溶率が５０％未満に低下するととも
に、Ａｌ−Ｆｅ−Ｍｎ系晶出物が粗大化して、加工性が
低下するためである。[0012] Fe forms an Al-Fe-Mn crystallized substance to improve the openability. Also, the crystal grains are refined to greatly improve the workability of the alloy. The reason for defining the content to be 0.3 wt% or less is that if it exceeds 0.3 wt%, the solid solution rate of Cu, which enhances the work hardening ability, decreases to less than 50%, and the Al-Fe-Mn crystallization occurs. This is because the material becomes coarse and the workability decreases.

【００１３】Ｃｒは強度向上に寄与する他、結晶粒を微
細化して加工性を高める。その含有量を０．１wt％以下
に規定した理由は、０．１wt％を超えると粗大な晶出物
が生成して局部的張出加工性などが低下するためであ
る。なお、Ｃｒは０．０１wt％以上含有されることによ
りその効果が十分発揮される。[0013] Cr contributes to the improvement of the strength and also refines the crystal grains to enhance the workability. The reason why the content is specified to be 0.1 wt% or less is that if the content exceeds 0.1 wt%, coarse crystallized substances are formed and the local stretchability and the like are reduced. The effect is sufficiently exhibited when Cr is contained at 0.01 wt% or more.

【００１４】Ｔｉは鋳造組織を微細化し加工性を向上さ
せる。その含有量を０．００１〜０．０５wt％に規定し
た理由は、０．００１wt％ではその効果が十分に得られ
ず、０．０５wt％を超えると粗大な晶出物が増加して成
形性が低下するためである。Ti refines the cast structure and improves workability. The reason that the content is defined as 0.001 to 0.05 wt% is that if the content is 0.001 wt%, the effect cannot be sufficiently obtained, and if the content exceeds 0.05 wt%, coarse crystals increase and formability increases. Is to be reduced.

【００１５】Ｓｉは不純物として含まれる。Ｓｉは０．
２wt％以下であれば成形性などを低下させるようなこと
はない。０．２wt％を超えると結晶粒界にＭｇ₂ Ｓｉ晶
出物が多量に生成し耐応力腐食割れ性が低下する。した
がって０．２wt％以下に規定する。[0015] Si is contained as an impurity. Si is 0.
If it is at most 2% by weight, the moldability will not be reduced. If it exceeds 0.2 wt%, a large amount of Mg ₂ Si crystallization will be generated at the crystal grain boundaries, and the stress corrosion cracking resistance will decrease. Therefore, it is specified to be 0.2 wt% or less.

【００１６】次に、本発明の成形用アルミニウム合金硬
質板の製造方法について説明する。本発明の硬質板は、
本発明で規定する組成のアルミニウム合金を連続鋳造、
または半連続鋳造など常法により鋳造し、得られる鋳塊
に、均質化処理、熱間圧延、冷間圧延、中間焼鈍、最終
冷間圧延、塗装焼付けの諸工程を順に施して製造され
る。本発明において、前記均質化処理を４５０〜５５０
℃で１時間以上加熱して施す理由は、４５０℃未満では
均質化に長時間を要し不経済であり、５５０℃を超える
と局部的な溶融が起きて表面欠陥の原因になり、また均
質化処理時間が１時間未満では均質化が十分進まないた
めである。Next, a method of manufacturing the aluminum alloy hard plate for forming according to the present invention will be described. The hard plate of the present invention,
Continuous casting of aluminum alloy of the composition specified in the present invention,
Alternatively, it is manufactured by casting by an ordinary method such as semi-continuous casting, and sequentially performing various steps of a homogenization treatment, hot rolling, cold rolling, intermediate annealing, final cold rolling, and paint baking on the obtained ingot. In the present invention, the homogenization treatment is performed at 450 to 550.
The reason for heating at a temperature of more than 450 ° C. for one hour or more is that it takes a long time to homogenize and is uneconomic. If the temperature exceeds 550 ° C., local melting occurs and causes surface defects. If the homogenization treatment time is less than one hour, homogenization will not sufficiently proceed.

【００１７】本発明において、熱間圧延および冷間圧延
は常法により行う。冷間圧延後の中間焼鈍を４００〜５
４０℃の温度範囲で２分以内施す理由は、４００℃未満
ではＣｕが十分固溶せず、５４０℃を超えると部分的な
溶解が起き、溶解部分が表面欠陥の原因となり、また保
持時間が２分を超えると結晶粒が粗大化して加工性が低
下するためである。なお、保持時間は０秒でも良い。す
なわち所定の中間焼鈍温度に到達後直ちに冷却しても良
い。また、昇温速度が１０℃／秒未満だとやはり結晶粒
が粗大化して加工性が低下する。さらに最高到達温度か
ら２００℃までの冷却速度を１℃／秒以上、２００℃未
満の冷却速度を５℃／秒以上とするのは冷却過程でＣｕ
などが析出するのを防ぐためであり、この条件を外れる
と所要の強度が得られない。最高到達温度から２００℃
までの温度範囲では、Ｃｕを含む化合物の析出の心配は
あまりなく冷却速度は１℃／秒以上で十分であるが、２
００℃を過ぎ１００℃までの温度範囲では析出し易いの
で冷却速度を５℃／秒以上に速める必要がある。In the present invention, hot rolling and cold rolling are carried out by a conventional method. 400-5 intermediate annealing after cold rolling
The reason for applying within a temperature range of 40 ° C. within 2 minutes is that Cu does not form a solid solution at a temperature lower than 400 ° C., and a partial melting occurs at a temperature higher than 540 ° C., and the melted portion causes surface defects. If the time exceeds 2 minutes, the crystal grains become coarse and the workability decreases. The holding time may be 0 seconds. That is, cooling may be performed immediately after reaching the predetermined intermediate annealing temperature. If the rate of temperature rise is less than 10 ° C./sec, the crystal grains are coarsened and the workability is lowered. Further, the cooling rate from the highest temperature to 200 ° C. is set at 1 ° C./sec or more, and the cooling rate at less than 200 ° C. is set at 5 ° C./sec or more.
This is to prevent precipitation of the like, and if the conditions are not satisfied, the required strength cannot be obtained. 200 ° C from maximum temperature
In the temperature range up to the above, there is not much concern about the precipitation of the compound containing Cu, and the cooling rate of 1 ° C./sec or more is sufficient.
In a temperature range from 00 ° C. to 100 ° C., precipitation tends to occur, so the cooling rate needs to be increased to 5 ° C./sec or more.

【００１８】本発明において、最終冷間圧延を施すのは
缶蓋として必要な強度を付与するためである。最終冷間
圧延率を５０％以上８０％未満に規定する理由は、圧延
率が５０％未満では十分な強度が得られず、８０％を超
えると、缶蓋などに用いたときに開缶性や耐圧性などが
経時的に低下するためである。また８０％を超えると、
圧延中に板材端部に割れが生じたり、材料異方性（耳率
など）が大きくなったりする。In the present invention, the final cold rolling is performed to impart necessary strength as a can lid. The reason why the final cold rolling reduction is specified to be 50% or more and less than 80% is that if the rolling reduction is less than 50%, sufficient strength cannot be obtained. This is because the pressure resistance and the pressure resistance decrease with time. If it exceeds 80%,
During rolling, cracks occur at the edges of the sheet material, or the material anisotropy (such as ear ratio) increases.

【００１９】焼付塗装はロールコータ等で高分子樹脂塗
料を塗布し、これを所定温度に加熱して行う。本発明に
おいて、焼付塗装を２００〜３００℃の温度に６０秒以
内保持して行う理由は、保持温度が３００℃を超える
か、もしくは保持時間が６０秒を超えると、材料の加工
組織が回復（転位密度の低減）して所要の強度が得られ
なくなり、加熱温度が２００℃未満では硬質板内部の残
留応力を完全に除去することができず、室温時効による
強度などの材料特性の変化を抑制することができないた
めである。なお、保持時間は、中間焼鈍と同じように０
秒でも良い。すなわち所定の焼付塗装温度に到達後直ち
に冷却しても良い。さらに焼付塗装での常温から２００
℃までの昇温速度を５℃／秒以上、２００℃から最高到
達温度までの昇温速度を１℃／秒以上とするのは昇温過
程でＣｕを含む化合物が析出するのを防ぐためであり、
この条件を外れると強度の低下を招く。常温から２００
℃までの温度域では析出し易いので昇温速度を５℃／秒
以上に速める必要があるが、２００℃を超え最高到達温
度までの温度範囲ではＣｕを含む化合物はあまり析出し
ないので、１℃／秒以上の昇温速度で十分である。The baking coating is performed by applying a polymer resin coating with a roll coater or the like and heating the coating to a predetermined temperature. In the present invention, the reason for performing the baking coating at a temperature of 200 to 300 ° C. within 60 seconds is that if the holding temperature exceeds 300 ° C. or the holding time exceeds 60 seconds, the processed structure of the material is recovered ( (Reduction in dislocation density), and the required strength cannot be obtained. If the heating temperature is lower than 200 ° C., the residual stress inside the hard plate cannot be completely removed, and changes in material properties such as strength due to aging at room temperature are suppressed. Because they cannot do it. The holding time is set to 0 as in the case of the intermediate annealing.
Seconds are fine. That is, cooling may be performed immediately after reaching a predetermined baking temperature. Furthermore, it is 200 from normal temperature by baking.
The reason why the rate of temperature rise to 5 ° C. is 5 ° C./sec or more and the rate of temperature rise from 200 ° C. to the maximum temperature is 1 ° C./sec or more is to prevent the precipitation of a compound containing Cu during the temperature rise process. Yes,
Deviating from this condition causes a decrease in strength. From room temperature to 200
It is necessary to increase the heating rate to 5 ° C./sec or more because the temperature is increased up to 5 ° C./sec. A heating rate of at least / sec is sufficient.

【００２０】以上に述べたように、本発明は、Ｃｕをそ
の含有量の５０％以上固溶させることにより合金の加工
硬化能を高め、その分最終冷間圧延率を下げて、転位密
度の低減（軟化）による開缶性や耐圧性などの特性の経
時的低下を抑制したものである。本発明の製造方法は、
合金の特性変化を抑制する目的で施す安定化熱処理が不
要で、従来法に比べて製造工程が短縮され生産性に優れ
る。As described above, the present invention increases the work hardening ability of an alloy by forming a solid solution of Cu by 50% or more of its content, lowers the final cold rolling reduction by that amount, and reduces the dislocation density. This suppresses the temporal deterioration of characteristics such as openability and pressure resistance due to reduction (softening). The production method of the present invention
No stabilization heat treatment is required for the purpose of suppressing a change in the properties of the alloy, and the manufacturing process is shortened and the productivity is excellent as compared with the conventional method.

【００２１】[0021]

【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に示す種々組成のアルミニウム合金を
通常のＤＣ鋳造法により鋳造して鋳塊とし、この鋳塊を
５００℃で６時間均質化処理したのち熱間圧延した。熱
間圧延は開始温度４８０℃、終了温度３１０±１０℃で
行った。次いで熱間圧延板を冷間圧延し、次いで中間焼
鈍を５２０℃で０秒行い、その後５２０℃から２００℃
までを３℃／秒の冷却速度で冷却し、２００℃を過ぎて
からは１０℃／秒の速度で冷却し、その後、最終冷間圧
延を圧延率７０％で行って厚さ０．２５ｍｍの板材を製
造した。この板材に、焼付塗装に相当する熱処理を施し
て成形用アルミニウム合金硬質板を製造した。前記熱処
理は２００℃までを１０℃／秒で昇温し、２００℃から
２５０℃までを３℃／秒で昇温し、２５０℃で３０秒間
保持した後１０℃／秒の速度で冷却して施した。The present invention will be described below in detail with reference to examples. (Example 1) Aluminum alloys having various compositions shown in Table 1 were cast by an ordinary DC casting method to form ingots. The ingots were homogenized at 500 ° C for 6 hours and then hot-rolled. Hot rolling was performed at a starting temperature of 480 ° C. and an ending temperature of 310 ± 10 ° C. Next, the hot-rolled sheet is cold-rolled, and then an intermediate annealing is performed at 520 ° C. for 0 second, and then from 520 ° C. to 200 ° C.
To 200 ° C., and after passing 200 ° C., at a rate of 10 ° C./sec., And then subjected to final cold rolling at a rolling reduction of 70% to a thickness of 0.25 mm. Plate material was manufactured. This plate was subjected to a heat treatment equivalent to baking coating to produce an aluminum alloy hard plate for forming. In the heat treatment, the temperature is raised to 200 ° C. at a rate of 10 ° C./second, the temperature is raised from 200 ° C. to 250 ° C. at a rate of 3 ° C./second, held at 250 ° C. for 30 seconds, and then cooled at a rate of 10 ° C./second. gave.

【００２２】得られた各々の硬質板について、Ｘ線回
折による（２００）面のＸ線回折角２θの半価巾、Ｃ
ｕの固溶率、リベット成形性、耐圧性を調べた。ま
た前記硬質板を１００℃で１日間保持したのち耐圧性
を調べた。さらに前記硬質板を缶蓋にプレス成形し１０
０℃で１日間保持（加速処理）したのち開缶性を調べ
た。結果を表２に示す。なお、前記１００℃で１日間保
持する加速処理は、室温で１年間保持することに相当す
る。また、リベット成形性が不良なものは開缶性は調査
しなかった。For each of the obtained hard plates, the half width of the X-ray diffraction angle 2θ of the (200) plane by X-ray diffraction, C
The solid solution rate, rivet formability, and pressure resistance of u were examined. After holding the hard plate at 100 ° C. for one day, the pressure resistance was examined. Further, the hard plate was press-formed into a can lid,
After being kept at 0 ° C. for one day (acceleration treatment), the openability of the can was examined. Table 2 shows the results. Note that the acceleration treatment at 100 ° C. for one day corresponds to holding at room temperature for one year. In addition, openability was not investigated for those having poor rivet formability.

【００２３】前記〜の試験方法は下記の通りであ
る。 Ｘ線回折：Ｃｕをターゲットとし、波長１．５４０５
ÅのＸ線を用いた。 Ｃｕの固溶率：硬質板をフェノールに溶解し、穴径が
０．１μｍのフィルターで漉して固形残渣を捕集し、こ
の固形残渣中に含まれるＣｕの定量分析値Ｂを下式に代
入して求めた。式中ＡはＣｕの含有量（添加量）であ
る。 Ｃｕの固溶率＝〔（Ａ−Ｂ）／Ａ〕×１００％ リベット成形性：試験個数５０個すべてが割れずに成
形できたとき良好（○）、１個でも割れたとき不良
（×）と判定した。 耐圧性：シェル成形体内部を窒素ガスで加圧して調べ
た。加速処理前のものは耐圧強度が６８５ＫＰａ以上を
良好（○）、６８５ＫＰａ未満を不良（×）と判定し
た。加速処理後のものは加速処理前と比べた強度低下が
５０ＫＰａ未満のとき良好（○）、５０ＫＰａ以上のと
き不良（×）と判定した。 開缶性：試験個数５０個すべてがスコア部分で切れた
とき良好（○）、スコア部分以外で切れたものが１個で
もあれば不良（×）と判定した。The above-mentioned test methods are as follows. X-ray diffraction: targeting Cu, wavelength 1.5405
Ｘ X-rays were used. Solid solution ratio of Cu: The hard plate is dissolved in phenol, and the solid residue is collected by straining with a filter having a hole diameter of 0.1 μm, and the quantitative analysis value B of Cu contained in the solid residue is substituted into the following equation. I asked. In the formula, A is the content (addition amount) of Cu. Solid solution rate of Cu = [(AB) / A] × 100% Rivet formability: good when all 50 test pieces could be formed without cracking (）), poor when even one piece cracked (×) It was determined. Pressure resistance: The inside of the shell molded body was examined by pressurizing it with nitrogen gas. Before the acceleration treatment, the pressure resistance strength was judged as good (（) when the pressure resistance was 685 KPa or more, and as poor (×) when the pressure resistance was less than 685 KPa. The specimen after the acceleration treatment was judged as good (（) when the decrease in strength as compared with that before the acceleration treatment was less than 50 KPa, and was judged as bad (X) when the strength was 50 KPa or more. Can openability: good (O) when all 50 test pieces were cut off at the score portion, and poor (x) when at least one piece was cut off at other than the score portion.

【００２４】[0024]

【表１】 [Table 1]

【００２５】[0025]

【表２】 [Table 2]

【００２６】表２より明らかなように、本発明例の No.
Ａ〜Ｋは、缶蓋として必要な特性をすべて満足した。こ
れに対して比較例の No.ＬはＭｇが少ないため No.Ｎは
Ｍｎが少ないため、いずれも硬質板の耐圧性および加速
処理後の開缶性が劣った。 No.Ｍ、Ｏ、Ｐ、Ｒ、Ｓ、Ｔ
は、それぞれＭｇ、Ｍｎ、Ｃｕ、Ｓｉ、Ｃｒ、Ｔｉが多
いためリベット成形性が劣った。 No.ＱはＦｅが多いた
めＣｕの固溶率が減少し、リベット成形性および加速処
理後の耐圧性が低下した。As is evident from Table 2, No. 1
AK satisfied all the properties required for the can lid. On the other hand, No. L of the comparative example had less Mg, and No. N had less Mn. Therefore, the pressure resistance of the hard plate and the openability after the acceleration treatment were all inferior. No. M, O, P, R, S, T
Has a large amount of Mg, Mn, Cu, Si, Cr, and Ti, respectively, and thus has poor rivet formability. In No. Q, since the amount of Fe was large, the solid solution rate of Cu decreased, and the rivet formability and the pressure resistance after the acceleration treatment decreased.

【００２７】（実施例２）表１に示すNo. Ｆの合金を用
い、表３に示す種々の製造条件により厚さ０．２５ｍｍ
のアルミニウム合金硬質板を製造した。缶蓋としての試
験評価は、実施例１と同じ方法により行った。結果を表
４に示す。(Example 2) Using an alloy of No. F shown in Table 1, a thickness of 0.25 mm was obtained under various manufacturing conditions shown in Table 3.
Aluminum alloy hard plate was manufactured. The test evaluation as a can lid was performed in the same manner as in Example 1. Table 4 shows the results.

【００２８】[0028]

【表３】 [Table 3]

【００２９】[0029]

【表４】 [Table 4]

【００３０】表４より明らかなように、本発明例のNo.1
〜16は、缶蓋として必要な特性をすべて満足した。これ
に対し、比較例の No.17は中間焼鈍での昇温速度が遅い
ため、 No.18は中間焼鈍での保持温度が低いため、No.1
7 は中間焼鈍での昇温速度が遅いため、No. 18は中間焼
鈍での保持温度が低かったため、No.19 は中間焼鈍での
保持時間が長過ぎたため、 No.20は中間焼鈍での冷却速
度が遅かったため、 No.21は中間焼鈍での冷却速度が遅
かったため、 No.22は冷間圧延率が低かったため、 No.
23は冷間圧延率が高かったため、 No.24は焼付塗装時の
２００℃までの昇温速度が遅かったため、 No.25は焼付
塗装時の２００℃を超えたときの昇温速度が遅かったた
め、 No.26,27 は焼付塗装時の保持温度が高いか、低か
ったため、 No.28は焼付塗装時の保持時間が長かったた
め、 No.29は焼付塗装時の冷却速度が遅かったため、い
ずれもＣｕの固溶率が５０％未満となるなどして、リベ
ット成形性、加速処理前後の耐圧性、加速処理前後の開
缶性のいずれかが低下した。As apparent from Table 4, No. 1 of the present invention example
No. 16 satisfied all the characteristics required for a can lid. On the other hand, No. 17 of the comparative example has a low temperature rising rate in the intermediate annealing, and No. 18 has a low holding temperature in the intermediate annealing.
No. 7 has a low temperature rising rate in the intermediate annealing, No. 18 has a low holding temperature in the intermediate annealing, and No. 19 has a too long holding time in the intermediate annealing. Because the cooling rate was slow, No. 21 was slow in cooling during the intermediate annealing, and No. 22 was low in cold rolling reduction.
No. 23 had a high rate of cold rolling, No. 24 had a slow heating rate up to 200 ° C. during baking, and No. 25 had a slow heating rate above 200 ° C. during baking. No. 26 and 27 had higher or lower holding temperature during baking, No. 28 had longer holding time during baking, and No. 29 had a slower cooling rate during baking. One of the rivet formability, the pressure resistance before and after the acceleration treatment, and the openability before and after the acceleration treatment was reduced, for example, because the solid solution rate of Cu became less than 50%.

【００３１】以上、本発明の成形用アルミニウム合金硬
質板を缶蓋に用いた場合について説明したが、本発明の
前記硬質板は、缶蓋以外の成形品に適用してもその効果
が十分に発現されるものである。The case where the aluminum alloy hard plate for forming of the present invention is used for a can lid has been described above. However, the hard plate of the present invention has a sufficient effect even when applied to a molded product other than the can lid. Is to be expressed.

【００３２】[0032]

【発明の効果】以上に述べたように、本発明の成形用ア
ルミニウム合金硬質板は、Ｃｕの固溶率が５０％と高い
ため、成形用として必要な強度が、低冷間圧延率つまり
低転位密度で得られる。従って、局部的張出加工性に優
れ、また経時的軟化が起き難いため、缶蓋などとして用
いたとき、開缶性や耐圧性が長期間良好に保持される。
本発明の成形用アルミニウム合金硬質板は条件を特定し
た通常の製造方法で容易に製造でき、特性を安定化させ
るための熱処理などを要さず生産性に優れる。依って工
業上顕著な効果を奏する。As described above, the aluminum alloy hard plate for forming according to the present invention has a high solid solution rate of Cu of 50%, so that the strength required for forming has a low cold rolling reduction, that is, a low cold rolling rate. Obtained at dislocation density. Therefore, since it is excellent in local overhanging workability and hardly softens over time, when used as a can lid or the like, the can openability and the pressure resistance are well maintained for a long time.
The aluminum alloy hard plate for forming according to the present invention can be easily manufactured by a normal manufacturing method in which the conditions are specified, and is excellent in productivity without requiring heat treatment or the like for stabilizing characteristics. Therefore, there is an industrially significant effect.

フロントページの続き (51)Int.Cl.⁶ 識別記号 ＦＩ Ｃ２２Ｆ 1/00 ６８２ Ｃ２２Ｆ 1/00 ６８２ ６８５ ６８５Ｚ ６８６ ６８６Ｂ ６９１ ６９１Ａ ６９１Ｂ ６９１Ｃ ６９２ ６９２Ａ ６９４ ６９４Ａ Continuation of the front page (51) Int.Cl. ⁶ Identification code FI C22F 1/00 682 C22F 1/00 682 682 685 685Z 686 686B 691 691A 691B 691C 692 692A 694 694A

Claims (3)

【特許請求の範囲】[Claims] 【請求項１】 Ｍｇを３．０〜５．０wt％、Ｃｕを０．
０５〜０．２wt％、Ｍｎを０．２〜０．７wt％、Ｆｅを
０．３wt％以下（０wt％を含む）、Ｃｒを０．１wt％以
下（０wt％を含む）、Ｔｉを０．００１〜０．０５wt％
含有し、残部がアルミニウムと不可避不純物からなるア
ルミニウム合金の硬質板に焼付塗装が施され、前記焼付
塗装後のアルミニウム合金硬質板の（２００) 結晶面の
Ｘ線回折角２θの半価巾が０．１６度以下、Ｃｕの含有
量の５０％以上がアルミニウムマトリックスに固溶して
いることを特徴とする成形用アルミニウム合金硬質板。1. An alloy containing 3.0 to 5.0% by weight of Mg and 0.1% by weight of Cu.
0.5 to 0.2 wt%, Mn 0.2 to 0.7 wt%, Fe 0.3 wt% or less (including 0 wt%), Cr 0.1 wt% or less (including 0 wt%), Ti 001-0.05wt%
The baking coating is applied to a hard plate of an aluminum alloy containing aluminum and unavoidable impurities, and the half-value width of the X-ray diffraction angle 2θ of the (200) crystal plane of the aluminum alloy hard plate after the baking coating is 0. An aluminum alloy hard plate for forming, characterized in that not more than 16 degrees and not less than 50% of the Cu content is dissolved in the aluminum matrix. 【請求項２】 請求項１記載の成形用アルミニウム合金
硬質板が用いられていることを特徴とする缶蓋。2. A can lid comprising the aluminum alloy hard plate for molding according to claim 1. 【請求項３】 Ｍｇを３．０〜５．０wt％、Ｃｕを０．
０５〜０．２wt％、Ｍｎを０．２〜０．７wt％、Ｆｅを
０．３wt％以下（０wt％を含む）、Ｃｒを０．１wt％以
下（０wt％を含む）、Ｔｉを０．００１〜０．０５wt％
含有し、残部がアルミニウムと不可避不純物からなるア
ルミニウム合金を溶解鋳造して鋳塊とし、この鋳塊に、
均質化処理、熱間圧延、冷間圧延、中間焼鈍、最終冷間
圧延、焼付塗装の各工程を順に施すアルミニウム合金硬
質板の製造方法において、前記均質化処理を４５０〜５
５０℃の温度範囲で１時間以上加熱して施し、中間焼鈍
を１０℃／秒以上の昇温速度で加熱し、４００〜５４０
℃の温度範囲で２分以内保持したのち、２００℃までを
１℃／秒以上の冷却速度で冷却し、２００℃を過ぎてか
ら１００℃までを５℃／秒以上の冷却速度で冷却して施
し、最終冷間圧延を５０％以上８０％未満の圧延率で施
し、焼付塗装を２００℃までを５℃／秒以上の昇温速度
で加熱し、２００℃を超えてから１℃／秒以上の昇温速
度で３００℃以下の所定温度まで加熱し、２００〜３０
０℃の所定温度に６０秒以内保持したのち１０℃／秒以
上の冷却速度で冷却して施すことを特徴とする請求項１
記載の成形用アルミニウム合金硬質板の製造方法。3. An alloy containing 3.0 to 5.0% by weight of Mg and 0.1% by weight of Cu.
0.5 to 0.2 wt%, Mn 0.2 to 0.7 wt%, Fe 0.3 wt% or less (including 0 wt%), Cr 0.1 wt% or less (including 0 wt%), Ti 001-0.05wt%
Containing, the remainder is an aluminum alloy consisting of aluminum and unavoidable impurities is melt-cast to form an ingot,
In a method for manufacturing an aluminum alloy hard plate, in which each step of homogenization, hot rolling, cold rolling, intermediate annealing, final cold rolling, and baking coating is sequentially performed, the homogenization treatment is performed at 450 to 5 times.
Heating is performed in a temperature range of 50 ° C. for 1 hour or more, and intermediate annealing is performed at a heating rate of 10 ° C./sec or more, and 400 to 540.
After the temperature is maintained within 2 minutes within a temperature range of 200 ° C., cooling to 200 ° C. is performed at a cooling rate of 1 ° C./second or more. The final cold rolling is performed at a rolling rate of 50% or more and less than 80%, and the baking coating is heated up to 200 ° C at a heating rate of 5 ° C / sec or more, and after the temperature exceeds 200 ° C, 1 ° C / sec or more. Is heated to a predetermined temperature of 300 ° C. or lower at a heating rate of 200 to 30 ° C.
2. The method according to claim 1, wherein the temperature is maintained at a predetermined temperature of 0 [deg.] C. for 60 seconds or less, and then cooled at a cooling rate of 10 [deg.] C./second or more.
A method for producing an aluminum alloy hard plate for molding according to the above.