JP2004197199A

JP2004197199A - Steel sheet for can having excellent non-aging property, workability and brittleness, and production method therefor

Info

Publication number: JP2004197199A
Application number: JP2002369941A
Authority: JP
Inventors: Toshiki Nonaka; 俊樹野中; Tsutomu Okamoto; 力岡本; Satoshi Takeuchi; 聡竹内
Original assignee: Nippon Steel Corp
Current assignee: Nippon Steel Corp
Priority date: 2002-12-20
Filing date: 2002-12-20
Publication date: 2004-07-15

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steel sheet for a can which has strength sufficient for a steel sheet for a can, and is excellent in workability and non-aging properties, and to provide a production method therefor. <P>SOLUTION: The steel sheet for a can is composed in such a manner that a steel sheet comprising, by weight, ≤0.006% C, ≤0.04% Si, 0.50 to 0.60% Mn, ≤0.02% P, ≤0.02% S, 0.005 to 0.1% Al, ≤0.01% N, and ≤0.005% Ca, and the balance iron with inevitable impurities satisfies the following inequalities (A) to (C), so that the steel sheet for a can maintaining strength, and excellent in workability and non-aging properties can be produced: inequality (A) is represented by C≤-0.01×Mn<SP>2</SP>+0.012×Mn+0.0014, inequality (B) is represented by C+0.02×Mn<SP>2</SP>-0.0048×Mn-0.01×P≤0.007712, and inequality (C) is represented by C+0.167×Mn+0.25×Si+0.01×P≥0.1. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、缶詰及び飲料缶等に用いられる錫めっき鋼板、クロムめっき鋼板、フィルムラミネート鋼板等の缶用鋼板の原板となる深絞り性、非時効性に優れた鋼板及びその製造方法に関するものである。
【０００２】
【従来の技術】
【特許文献１】特開昭５９−３５６３２号公報
【特許文献２】特開平１−１８８６２７号公報
【０００３】
従来の２ピース缶用鋼板は加工性の良い軟質原板が用いられていた。ところが、近年では鋼板の板厚がより薄いものが要求されるようになったが、この極薄材はｒ値が低いため、深絞り性が悪く、加工途中でカップの底周辺が破断することがあった。そのため、深絞り鋼板を利用するようになった。
【０００４】
この深絞り鋼板では、一般にＴｉやＮｂを添加して炭化物を生成することで固溶Ｃを削減する製法がとられてきた。しかし、コストアップや食品衛生上の問題があり、缶用鋼板にはＴｉ、Ｎｂの添加は無い方が好ましい。そこで、Ｔｉ、Ｎｂ無添加の成分系での製造が考えられたが、強度を保つためにはＣ量を増やす必要があり、降伏点伸びが発生し非時効性が悪くなる問題が発生した。更に求められる鋼板の板厚が薄くなってきており、充分な加工性は保ちつつ加えてある程度の強度も求められるようになった。
【０００５】
【発明が解決しようとする課題】
本発明の課題は、加工性の高い深絞り鋼板で、リジング性を保ちかつ非時効性の高い缶用鋼板及びその製造を達成することにある。深絞り性を上げるにはＣ量を低減することが必要であるが、リジング性が悪くなる課題があり、また強度を保つためにＣ量を増加すると非時効性が悪くなる課題が発生する。本発明は非時効性に対するＣ、Ｍｎの影響を明らかにし、また加工性や強度、低温脆性の要求も満たす成分系を発明し、上記課題を解決する缶用鋼板を製造することを目的とする。
【０００６】
【課題を解決するための手段】
上記の目的を達成すべく種々実験、検討を重ねた結果、非時効性や加工性、強度を満たすＣとＭｎとＰの関係式を見出した。この結果、主要５元素を中心とした成分系である深絞り鋼板にて、非時効性に優れた缶用鋼板を製造することを可能とするに至ったのである。その要旨は、下記の通りである。
【０００７】
（１）重量％にて
Ｃ：０．００６％以下、
Ｓｉ：０．０４％以下、
Ｍｎ：０．５０％超、０．６０％以下、
Ｐ：０．０２％以下
Ｓ：０．０２％以下
Ａｌ：０．００５％超〜０．１％以下、
Ｎ：０．０１％以下、
を含有し、
Ｃ≦−0.01×Ｍｎ²＋0.012 ×Ｍｎ＋0.0014 （Ａ）
Ｃ＋0.02×Ｍｎ²−0.0048×Ｍｎ−0.01×Ｐ≦0.007712 （Ｂ）
Ｃ＋0.167 ×Ｍｎ＋0.25×Ｓｉ＋0.01×Ｐ≧0.1 （Ｃ）
のいずれの式も満たし、かつ残部が鉄および不可避的不純物からなる、非時効性、加工性、脆性に優れた缶用鋼板。
（２）前記、（１）に記した鋼の成分において、更にＣａ：０．００５％以下を含有し、残部が鉄および不可避的不純物からなる、非時効性、加工性、脆性に優れた缶用鋼板。
（３）鋼板に表面処理を施したことを特徴とする（１）又は（２）に記載の非時効性、加工性、脆性に優れた缶用鋼板。
（４）表面処理がクロムめっきまたは錫めっきまたはニッケルめっきであることを特徴とする（３）に記載の非時効性、加工性、脆性に優れた缶用鋼板。
（５）（３）又は（４）に記した鋼板に、さらにフィルムラミネート処理をする非時効性、加工性、脆性に優れた缶用鋼板。
（６）前記、（１）または（２）に記した鋼の成分において、Ar₃点以上の仕上温度で熱間圧延を施し、５００〜８００℃で捲取り、次いで通常の酸洗の後、圧下率を５０〜９８％として一次冷間圧延後、連続焼鈍工程で６００℃以上オーステナイト化温度以下に均熱して再結晶焼鈍を施し、次いで圧下率４０％未満の二次冷間圧延を施した非時効性、加工性、脆性に優れた缶用鋼板の製造方法。
【０００８】
【発明の実施の形態】
本発明は０．００６％以下のＣを含有する鋼にＭｎを添加、更にＳｉ、Ｐ、Ｓ、Ａｌ、Ｎを若干量添加、必要に応じてＣａを添加した缶用鋼板である。そして、ＣとＭｎとＰ量の関係から、加工性と強度を保ち、かつ非時効性を強化し、低温脆性にも優れたものである。本発明は以上のような骨子に基づくが、以下に本発明の個々の構成要件について詳細に説明する。
【０００９】
Ｃの含有量が多くなると固溶Ｃが増えるために非時効性が悪化する。一方でＭｎにはそれを抑制する効果があるため、下式（Ａ）の範囲を指定する。
Ｃ≦−0.01×Ｍｎ²＋0.012 ×Ｍｎ＋0.0014 （Ａ）
図１の結果から、式（Ａ）で示したある特定範囲にて非時効性が良い事が言える。
【００１０】
また、加工性を得るためには一定以上のｒ値が必要であり、更にイヤリング性を良くするためにはΔｒ値を０に近づけることが重要だが、これにはＭｎ添加量を抑える必要がある。加えて結晶粒径を小さくすることも加工性が良くなることに繋がるが、Ｃ、Ｍｎ、Ｐを添加することで効果が表れる。ただしある量以上に添加しても効果はあがらない。以上をふまえて下式（Ｂ）で範囲を指定する。
Ｃ＋0.02×Ｍｎ²−0.0048×Ｍｎ−0.01×Ｐ≦0.007712 （Ｂ）
図２の結果から、式（Ｂ）で示したある特定範囲にて加工性が良い事が言える。
【００１１】
缶用鋼板では軽量化が求められ鋼板の板厚は従来から薄いものが求められており、そのため強度も必要になってくる。よって下式（Ｃ）を満たすものとする。
Ｃ＋0.167 ×Ｍｎ＋0.25×Ｓｉ＋0.01×Ｐ≧0.1 （Ｃ）
図３の結果から、式（Ｃ）で示したある特定範囲にて加工性が良い事が言える。尚、強度を保つためにはＭｎは０．５％超が望ましい。
【００１２】
以下に本発明の成分の限定理由について述べる．
Ｃは、鋼の時効性に影響を及ぼす元素であり、含有量が多くなる固溶Ｃが増えるために非時効性は悪化する。従って、非時効性を得るために０．００６％以下とする。また、添加量が増加すると加工性が劣化し深絞り性が損なわれるために０．００４％以下が更に望ましい。一方でリジングの問題があるために０．００１％以上が望ましい。
【００１３】
Ｓｉは、ブリキの耐食性を劣化させるほかに、材質を大きく硬質化する置換型固溶体強化元素であり、延性、加工性を向上させるに好ましくない元素である。そこで、０．０４% を上限とする。
【００１４】
Ｍｎは、式（Ａ）から（Ｃ）において決定される。更に０．５％以下では、強度を保つことが厳しくなり、かつ固溶Ｃによる降伏点伸び発生を抑制することが難しくなるために０．５％超が望ましい。また、０．６％を越えると加工性が劣化する場合があるため０．６％を上限とすることが望ましい。
【００１５】
Ｐは鋼板の強度を上げる元素であり、硬質化により加工性が悪くなる。また、耐食性を劣化させる元素であるため、上限を０．０２％とする。
【００１６】
Ｓは鋼中に存在しない方が好ましい元素であり、特に加工性を高めるためには低い方が望ましく上限を０．０２％とする。
【００１７】
Ａｌは、ＡｌＮとしてＮをトラップし固溶Ｎを減少させることが好ましいので０．００５％超添加する。ただし添加量が増加すると加工性が劣化するため０．１％以下を上限とする。
【００１８】Ｎは、加工性を確保するためには少ない方が良い。０．０１％を越えると加工性が劣化してくるので、０．０１% を上限とする。
【００１９】
Ｃａは、介在物の形態制御に有効であり、薄物鋼板の加工性を良くする事や低温脆性を良くすることが可能である。しかし、過剰に存在すると熱間加工性が悪くなり望ましくないため０．００５％以下とする。
【００２０】
次に製造方法について説明する。製造方法は一般に行われている熱延鋼板、冷延鋼板、めっき鋼板の製造方法で構わない。特に熱間圧延でフェライト粒にひずみが過度に加わり加工性が低下するのを防ぐには熱間圧延をＡｒ₃以上で行い、また、高温すぎても焼鈍後の再結晶粒径は必要以上に粗大化するため、９４０℃以下が望ましい。巻き取り温度については、高温にすれば再結晶や粒成長が促進され、加工性の向上が望まれるが、熱間圧延時に発生するスケール生成も促進され酸洗性が低下するので、８００℃以下とする。一方で低温になりすぎると、リジングのような不均一変形を生じる集合組織が生じることがあり、また炭化物が生成しにくくなるので時効性も悪くなるため、５００℃以上とする。
【００２１】
酸洗後の冷間圧延は、圧下率が低いと鋼板の形状矯正が難しくなるため５０％以上とする。また、９８％を超える圧下率で圧延すると、局部延性の劣化が発生することがあるため望ましくない。さらに、加工性を良くするために高ｒ値にしたいため、好ましくは７０％以上９５％以下の範囲が良い。
【００２２】
連続焼鈍温度は低すぎると未再結晶の状態になり硬質化し、逆に高すぎると粒が粗大化するという問題点があるので、６００℃以上オーステナイト温度域以下とする。その後二次冷間圧延を行うが、Ｔ１〜Ｔ６、ＤＲ８〜ＤＲ１０の調質度を得るために、適切な圧下率をとれば良い。ただし、加工性の悪化を防ぐため圧延率は４０％以下とする。
【００２３】
なお、本鋼板のめっきは通常のクロムめっき、錫めっき、ニッケルめっき等のいずれにも適用できる。また、鋼板上やめっき鋼板上にフィルムラミネートを行う用途にも適用できる。
【００２４】
【実施例】
次に本発明を実施例に基づいて説明する。
表１に示す成分の鋼を溶製し、常法に従い連続鋳造でスラブとした。符号１〜２１が本発明に従った成分の鋼で符号２２〜２４は式（Ａ）から逸脱するものであり、符号２５〜２７は式（Ｂ）から逸脱するものであり、符号２８〜３０は式（Ｃ）から逸脱するものである。これらの鋼を加熱炉中で１１６０℃〜１２５０℃で加熱し、８７０℃〜９００℃の仕上げ温度で熱間圧延を行い、６５０℃〜７５０℃にて巻き取る。これに続いて酸洗後、冷間圧延を行い、６５０℃〜７５０℃×６０ｓｅｃの再結晶焼鈍、３２％の圧下率で二次冷間圧延を行い冷延鋼板となした。
【００２５】
得られた鋼板のうち符号１〜７、２２〜２４をＪＩＳ５号引張試験片に加工し、２２０℃×１００ｓの状態で放置した後、機械特性値の評価を行った。各試験片の降伏点伸びを表２に示す。この結果、１〜７の本発明に従った成分では降伏点伸びは０．０４％以下と小さくストレッチャーストレインの発生は認められない。しかし、比較例としてあげている２２〜２４では降伏点伸びが１％を超え、非時効性が悪いことがいえる。
【００２６】
続いて符号８〜１４、２５〜２７をＪＩＳ５号試験片に加工しｒ値とΔｒ値の評価を行った。その結果を表３に示す。この結果、本発明範囲内であればｒ値が高く、かつΔｒ値も比較例よりもはるかに良い値を示しており、深絞り性、加工性に優れた缶用鋼板が得られたことが明らかである。
【００２７】
続いて符号１５〜２１、２８〜３０をＪＩＳ５号試験片に加工し引張強度の評価を行った。その結果を表４に示す。今回ＤＲ９にて６２０±３０MPa を狙ったものであるが、本発明範囲内であれば条件を満たすが、比較例では強度が足りないことがいえる。尚、二次冷延率をこれ以上高くしてもほとんど強度は高くならない。
【００２８】
【表１】

【００２９】
【表２】

【００３０】
【表３】

【００３１】
【表４】

【００３２】
【発明の効果】
本発明によれば、十分な成形性と強度を有しかつ、非時効性に優れた缶用鋼板を製造することが出来る。本発明の方法による鋼板は、従来の鋼板と比較してｒ値が高くかつ面内異方性も低いため、深絞り性や加工性が良く成形時のトラブルが減り歩留も上がるという利点がある。
【図面の簡単な説明】
【図１】本発明の式（Ａ）と非時効性の関係を示す説明図である。
【図２】本発明の式（Ｂ）と加工性の関係を示す説明図である。
【図３】本発明の式（Ｃ）と強度の関係を示す説明図である。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a steel sheet excellent in deep drawability, non-aging property and a method for producing a steel sheet for cans such as tin-plated steel sheets, chrome-plated steel sheets, and film-laminated steel sheets used for cans and beverage cans. is there.
[0002]
[Prior art]
[Patent Document 1] JP-A-59-35632 [Patent Document 2] JP-A-1-188627
Conventional steel plates for two-piece cans used soft original plates having good workability. However, in recent years, a thinner steel plate has been required, but since this ultra-thin material has a low r-value, deep drawability is poor, and the vicinity of the bottom of the cup is broken during processing. was there. For this reason, deep drawing steel sheets have been used.
[0004]
In the case of this deep-drawn steel sheet, a manufacturing method has been generally adopted in which Ti and Nb are added to generate carbides to reduce solid solution C. However, there is a problem in cost increase and food hygiene, and it is preferable that the steel sheet for cans does not contain Ti and Nb. Therefore, production using a component system free of Ti and Nb was considered, but it was necessary to increase the amount of C in order to maintain strength, and there was a problem that elongation at the yield point occurred and non-aging property deteriorated. Further, the required thickness of a steel sheet has been reduced, and a certain degree of strength has been required in addition to sufficient workability.
[0005]
[Problems to be solved by the invention]
An object of the present invention is to achieve a deep-drawn steel sheet having high workability, which maintains ridging properties and has a high non-aging property, and a production thereof. To increase the deep drawability, it is necessary to reduce the amount of C. However, there is a problem that the ridging property is deteriorated, and when the amount of C is increased to maintain the strength, a problem that the non-aging property is deteriorated occurs. An object of the present invention is to clarify the effects of C and Mn on non-aging properties, and to invent a component system that also satisfies the requirements for workability, strength, and low-temperature brittleness, and to produce a steel sheet for a can that solves the above-mentioned problems. .
[0006]
[Means for Solving the Problems]
As a result of repeated experiments and studies to achieve the above object, a relational expression between C, Mn, and P that satisfies non-aging property, workability, and strength was found. As a result, it has become possible to produce a steel sheet for cans with excellent non-aging properties using a deep drawn steel sheet which is a component system mainly composed of the five main elements. The summary is as follows.
[0007]
(1) C: 0.006% or less by weight%
Si: 0.04% or less,
Mn: more than 0.50%, 0.60% or less,
P: 0.02% or less S: 0.02% or less Al: more than 0.005% to 0.1% or less,
N: 0.01% or less,
Containing
C ≦ −0.01 × Mn ² + 0.012 × Mn + 0.0014 (A)
C + 0.02 × Mn ² −0.0048 × Mn−0.01 × P ≦ 0.007712 (B)
C + 0.167 × Mn + 0.25 × Si + 0.01 × P ≧ 0.1 (C)
The steel sheet for cans, which satisfies all the above formulas and the balance is composed of iron and unavoidable impurities, is excellent in non-aging property, workability, and brittleness.
(2) A can excellent in non-aging property, workability, and brittleness, which further contains 0.005% or less of Ca in the steel component described in (1) above, with the balance being iron and unavoidable impurities. For steel plate.
(3) The steel sheet for cans excellent in non-aging property, workability, and brittleness according to (1) or (2), wherein the steel sheet is subjected to a surface treatment.
(4) The steel sheet for cans excellent in non-aging property, workability, and brittleness according to (3), wherein the surface treatment is chrome plating, tin plating, or nickel plating.
(5) A steel sheet for cans excellent in non-aging property, workability, and brittleness in which a film lamination treatment is further performed on the steel sheet described in (3) or (4).
(6) In the steel component described in the above (1) or (2), hot rolling is performed at a finishing temperature of not less than the Ar ₃ point, wound up at 500 to 800 ° C., and then after ordinary pickling, After the primary cold rolling at a reduction of 50 to 98%, the steel was subjected to recrystallization annealing by soaking in a continuous annealing step at a temperature of 600 ° C. or more and an austenitizing temperature or less, and then subjected to secondary cold rolling at a reduction of less than 40%. A method for producing a steel sheet for cans having excellent non-aging, workability and brittleness.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
The present invention is a steel sheet for cans obtained by adding Mn to steel containing 0.006% or less of C, further adding a small amount of Si, P, S, Al, and N, and adding Ca as necessary. And, from the relationship between C, Mn, and P content, it maintains workability and strength, strengthens non-aging properties, and is also excellent in low-temperature brittleness. Although the present invention is based on the above-described outline, individual components of the present invention will be described in detail below.
[0009]
When the content of C increases, the amount of solid solution C increases, so that the non-aging property deteriorates. On the other hand, since Mn has the effect of suppressing it, the range of the following equation (A) is specified.
C ≦ −0.01 × Mn ² + 0.012 × Mn + 0.0014 (A)
From the results of FIG. 1, it can be said that the non-aging property is good in a specific range shown by the formula (A).
[0010]
Further, in order to obtain the workability, it is necessary that the r value is equal to or more than a certain value. In order to further improve the earring property, it is important to make the Δr value close to 0, but it is necessary to suppress the amount of added Mn. . In addition, reducing the crystal grain size leads to improvement in workability, but the effect is exhibited by adding C, Mn, and P. However, the effect does not increase even if added in a certain amount or more. Based on the above, the range is specified by the following equation (B).
C + 0.02 × Mn ² −0.0048 × Mn−0.01 × P ≦ 0.007712 (B)
From the result of FIG. 2, it can be said that the workability is good in a certain specific range shown by the equation (B).
[0011]
In steel plates for cans, weight reduction is required, and the thickness of the steel plate has conventionally been required to be thin, so that strength is also required. Therefore, the following equation (C) is satisfied.
C + 0.167 × Mn + 0.25 × Si + 0.01 × P ≧ 0.1 (C)
From the results of FIG. 3, it can be said that the workability is good in a specific range shown by the formula (C). In order to maintain the strength, Mn is desirably more than 0.5%.
[0012]
The reasons for limiting the components of the present invention are described below.
C is an element that affects the aging property of steel, and the non-aging property deteriorates because the amount of solid solution C whose content increases increases. Therefore, in order to obtain non-aging properties, the content is made 0.006% or less. Further, when the addition amount increases, the workability is deteriorated and the deep drawability is impaired, so that the content is more preferably 0.004% or less. On the other hand, 0.001% or more is desirable because of the problem of ridging.
[0013]
Si is a substitutional solid solution strengthening element that not only deteriorates the corrosion resistance of the tin plate but also hardens the material significantly, and is an element that is not preferable for improving ductility and workability. Therefore, the upper limit is set to 0.04%.
[0014]
Mn is determined in equations (A) to (C). Further, if it is 0.5% or less, it is difficult to maintain the strength, and it is difficult to suppress the yield point elongation due to solid solution C. If the content exceeds 0.6%, the workability may be deteriorated. Therefore, it is desirable to set the upper limit to 0.6%.
[0015]
P is an element that increases the strength of the steel sheet, and hardens the workability. Further, since it is an element that deteriorates corrosion resistance, the upper limit is made 0.02%.
[0016]
S is an element that is preferably not present in the steel. In particular, S is desirably low in order to enhance workability, and the upper limit is made 0.02%.
[0017]
Al is preferably added as more than 0.005% because it is preferable to trap N as AlN to reduce solid solution N. However, when the added amount increases, the workability deteriorates, so the upper limit is 0.1% or less.
N is preferably small in order to ensure workability. If it exceeds 0.01%, the workability deteriorates, so the upper limit is made 0.01%.
[0019]
Ca is effective in controlling the form of inclusions, and can improve the workability of a thin steel plate and the low-temperature brittleness. However, if it exists in excess, the hot workability deteriorates, which is undesirable.
[0020]
Next, a manufacturing method will be described. The manufacturing method may be a generally used method for manufacturing a hot-rolled steel sheet, a cold-rolled steel sheet, or a plated steel sheet. In particular, to prevent the workability from deteriorating due to excessive strain applied to the ferrite grains in hot rolling, hot rolling is performed with Ar ₃ or more.Also, even if the temperature is too high, the recrystallized grain size after annealing becomes unnecessarily large. 940 ° C. or lower is desirable for coarsening. As for the winding temperature, recrystallization and grain growth are promoted at a high temperature, and improvement in workability is desired. However, scale formation generated during hot rolling is promoted and pickling property is reduced, so that the temperature is 800 ° C. or less. And On the other hand, if the temperature is too low, a texture that causes non-uniform deformation such as ridging may be generated, and carbides are hardly generated, so that the aging property is deteriorated.
[0021]
In cold rolling after pickling, if the rolling reduction is low, it is difficult to correct the shape of the steel sheet, so that it is set to 50% or more. Rolling at a rolling reduction of more than 98% is not desirable because local ductility may deteriorate. Further, in order to increase the r value in order to improve the workability, the range is preferably 70% or more and 95% or less.
[0022]
If the continuous annealing temperature is too low, it becomes unrecrystallized and becomes hard, and if it is too high, there is a problem that the grains become coarse. After that, the secondary cold rolling is performed, but in order to obtain the temper degrees T1 to T6 and DR8 to DR10, an appropriate rolling reduction may be taken. However, the rolling ratio is set to 40% or less in order to prevent deterioration in workability.
[0023]
The plating of the steel sheet can be applied to any of ordinary chrome plating, tin plating, nickel plating and the like. Further, the present invention can also be applied to an application in which a film is laminated on a steel plate or a plated steel plate.
[0024]
【Example】
Next, the present invention will be described based on examples.
Steels having the components shown in Table 1 were melted and continuously cast into slabs according to a conventional method. Reference numerals 1 to 21 are steel components according to the present invention, reference numerals 22 to 24 deviate from the formula (A), reference numerals 25 to 27 deviate from the formula (B), and reference numerals 28 to 30 Deviates from equation (C). These steels are heated in a heating furnace at 1160C to 1250C, hot rolled at a finishing temperature of 870C to 900C, and wound at 650C to 750C. Subsequently, after pickling, cold rolling was performed, and recrystallization annealing was performed at 650 ° C. to 750 ° C. × 60 sec, and secondary cold rolling was performed at a rolling reduction of 32% to obtain a cold-rolled steel sheet.
[0025]
Of the obtained steel sheets, reference numerals 1 to 7, 22 to 24 were processed into JIS No. 5 tensile test pieces, left at 220 ° C. × 100 s, and evaluated for mechanical property values. Table 2 shows the yield point elongation of each test piece. As a result, in the components 1 to 7 according to the present invention, the yield point elongation was as small as 0.04% or less, and the occurrence of stretcher strain was not recognized. However, in Comparative Examples 22 to 24, the yield point elongation exceeded 1%, indicating that the non-aging property was poor.
[0026]
Subsequently, reference numerals 8 to 14, 25 to 27 were processed into JIS No. 5 test pieces, and the r value and the Δr value were evaluated. Table 3 shows the results. As a result, within the range of the present invention, the r value was high, and the Δr value also showed a much better value than the comparative example, and it was found that a deep drawing property, a steel sheet for can excellent in workability was obtained. it is obvious.
[0027]
Subsequently, reference numerals 15 to 21 and 28 to 30 were processed into JIS No. 5 test pieces, and the tensile strength was evaluated. Table 4 shows the results. This time, DR9 is aimed at 620 ± 30 MPa, but the condition is satisfied within the range of the present invention, but it can be said that the strength is insufficient in the comparative example. The strength hardly increases even if the secondary cold rolling reduction is increased further.
[0028]
[Table 1]

[0029]
[Table 2]

[0030]
[Table 3]

[0031]
[Table 4]

[0032]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, it has sufficient formability and intensity | strength, and can manufacture the steel plate for cans excellent in the non-aging property. Since the steel sheet according to the method of the present invention has a higher r-value and a lower in-plane anisotropy than conventional steel sheets, it has the advantage of having good deep drawability and workability, reducing trouble during forming, and increasing the yield. is there.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing the relationship between the formula (A) of the present invention and non-aging properties.
FIG. 2 is an explanatory diagram showing the relationship between the formula (B) of the present invention and workability.
FIG. 3 is an explanatory diagram showing the relationship between the formula (C) and the strength according to the present invention.

Claims

C: 0.006% or less by weight%,
Si: 0.04% or less,
Mn: more than 0.50%, 0.60% or less,
P: 0.02% or less S: 0.02% or less Al: more than 0.005% to 0.1% or less,
N: 0.01% or less,
Containing
C ≦ −0.01 × Mn ² + 0.012 × Mn + 0.0014 (A)
C + 0.02 × Mn ² −0.0048 × Mn−0.01 × P ≦ 0.007712 (B)
C + 0.167 × Mn + 0.25 × Si + 0.01 × P ≧ 0.1 (C)
The steel sheet for cans, which satisfies all the above formulas and the balance is composed of iron and unavoidable impurities, is excellent in non-aging property, workability, and brittleness.

2. The steel sheet for cans according to claim 1, further comprising Ca: 0.005% or less, with the balance being iron and unavoidable impurities, and having excellent non-aging properties, workability, and brittleness.

The steel sheet for cans excellent in non-aging property, workability, and brittleness according to claim 1 or 2, wherein the steel sheet is subjected to a surface treatment.

4. The steel sheet for cans excellent in non-aging property, workability and brittleness according to claim 3, wherein the surface treatment is chrome plating, tin plating or nickel plating.

A steel sheet for cans which is further excellent in non-aging property, workability, and brittleness by further laminating a film to the steel sheet according to claim 3 or 4.

In the steel component described in claim 1 or 2, hot rolling is performed at a finishing temperature of not less than Ar ₃ points, winding is performed at 500 to 800 ° C, and then, after normal pickling, the rolling reduction is 50 to 50 ° C. After the first cold rolling at 98%, in a continuous annealing step, the steel is subjected to recrystallization annealing by soaking at a temperature equal to or higher than 600 ° C. and lower than the austenitizing temperature, and then subjected to secondary cold rolling at a rolling reduction of 40% or less. Of steel sheet for cans with excellent brittleness and brittleness.