JP3536684B2 - Steel wire with excellent wire drawing workability - Google Patents
Steel wire with excellent wire drawing workabilityInfo
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- JP3536684B2 JP3536684B2 JP26982298A JP26982298A JP3536684B2 JP 3536684 B2 JP3536684 B2 JP 3536684B2 JP 26982298 A JP26982298 A JP 26982298A JP 26982298 A JP26982298 A JP 26982298A JP 3536684 B2 JP3536684 B2 JP 3536684B2
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- steel
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Description
【０００１】[0001]
【発明の属する技術分野】本発明は、伸線加工性に優れ
た鋼線材に関する。より詳しくは、例えば、ワイヤロー
プ、ＰＣ鋼線、ビードワイヤー、スチールコードなどの
用途に好適な伸線加工性に優れた鋼線材に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel wire rod excellent in wire drawability. More specifically, for example, the present invention relates to a steel wire rod excellent in drawability suitable for applications such as wire rope, PC steel wire, bead wire, and steel cord.
【０００２】[0002]
【従来の技術】ワイヤロープ、ＰＣ鋼線は、一般に、熱
間圧延して得た鋼線材（以下、「鋼線材」を単に「線
材」という）に伸線加工を施し、更に、焼入れ焼戻しの
調質処理、あるいはブルーイング処理を施して製造され
る。又、自動車のラジアルタイアの補強材として用いら
れるスチールコード用極細鋼線は、以下に示すような工
程で製造されている。すなわち、熱間圧延後調整冷却し
た線径が約５．５ｍｍの線材を、１次伸線加工して直径
を３ｍｍ前後にし、次いで、パテンティング処理を行
い、更に２次伸線加工して１．５ｍｍ前後の直径にす
る。この後、最終パテンティング処理を行い、次いで、
ブラスメッキを施し、更に最終湿式伸線加工を施して直
径０．２〜０．４ｍｍにする。このようにして得られた
極細鋼線を、更に撚り加工で複数本撚り合わせて撚鋼線
とすることでスチールコードが製造される。2. Description of the Related Art In general, a wire rope and a PC steel wire are subjected to wire drawing to a steel wire obtained by hot rolling (hereinafter, "steel wire" is simply referred to as "wire") and further subjected to quenching and tempering. It is manufactured by subjecting it to a tempering treatment or a bluing treatment. An ultrafine steel wire for a steel cord used as a reinforcing material for a radial tire of an automobile is manufactured by the following process. That is, a wire rod having a diameter of about 5.5 mm adjusted and cooled after hot rolling is subjected to a primary drawing to a diameter of about 3 mm, then subjected to a patenting process, and further subjected to a secondary drawing to obtain a wire having a diameter of about 1 mm. The diameter is about 0.5 mm. After this, a final patenting process is performed, and then
Brass plating is performed and final wet drawing is performed to a diameter of 0.2 to 0.4 mm. The steel cord is manufactured by twisting a plurality of the extra-fine steel wires obtained in this manner by twisting into a twisted steel wire.
【０００３】一般に、線材を鋼線に加工する際に断線が
生ずると、生産性と歩留りが大きく低下してしまう。し
たがって、上記技術分野に属する線材は、伸線加工時、
特にスチールコードを製造する場合は強度の冷間加工が
行われる湿式伸線加工時に、断線しないことが強く要求
される。In general, when a wire is broken into a steel wire when it is broken, productivity and yield are greatly reduced. Therefore, wires belonging to the above technical field, at the time of wire drawing,
In particular, in the case of producing a steel cord, it is strongly required not to break the wire at the time of wet drawing in which strong cold working is performed.
【０００４】更に、スチールコードの製造の場合、熱間
圧延した直径５．５ｍｍの線材を直径が約１．５ｍｍの
鋼線にするのに多くの中間処理工程を要し、製造コスト
の上昇を招いている。したがって、最終製品の性能を低
下させることなく、製造工程を簡略化したいとする産業
界からの要望が大きくなっている。このため、Ｃ含有量
が０．７％未満の比較的強度の低い炭素鋼線材などで
は、中間処理を省略して、例えば直径５．５ｍｍから
１．５ｍｍまで直接に伸線する技術が開発されている。
なお、前記伸線における真歪量は２．６０である。ここ
で、真歪（ε）は線材の直径（ｄ0 ）と伸線後の鋼線の
直径（ｄ）を用いて下記の（ｉ）式で表されるものであ
る。Further, in the case of manufacturing a steel cord, many intermediate processing steps are required to convert a hot-rolled 5.5 mm-diameter wire into a steel wire having a diameter of about 1.5 mm, thereby increasing the manufacturing cost. Inviting. Therefore, there is an increasing demand from the industry to simplify the manufacturing process without deteriorating the performance of the final product. For this reason, for a relatively low-strength carbon steel wire rod having a C content of less than 0.7%, a technique for directly drawing a wire from 5.5 mm to 1.5 mm in diameter without intermediate treatment has been developed. ing.
In addition, the true strain amount in the wire drawing is 2.60. Here, the true strain (ε) is represented by the following equation (i) using the diameter (d 0 ) of the wire and the diameter (d) of the drawn steel wire.
【０００５】ε＝２ｌｏｇe（ｄ0／ｄ）・・・（ｉ）
一方では、近年、種々の目的からスチールコードなどを
軽量化する動きが高まってきた。このため、前記の各種
製品に対して高強度が要求されるようになり、上記のＣ
含有量が０．７％未満の炭素鋼線材などでは、所望の高
強度が得られなくなっている。このため、Ｃ含有量が高
くて鋼線に高い強度を確保させることができ、しかも前
記の中間処理を省略できるような伸線加工性に優れた線
材に対する要求が極めて大きくなっている。Ε = 2log e (d 0 / d) (i) On the other hand, in recent years, there has been an increasing movement to reduce the weight of steel cords and the like for various purposes. For this reason, high strength is required for the various products described above, and the above C
With a carbon steel wire having a content of less than 0.7%, a desired high strength cannot be obtained. For this reason, there is an extremely large demand for a wire rod which has a high C content and can secure a high strength to a steel wire, and which has excellent drawability such that the intermediate treatment can be omitted.
【０００６】又、ワイヤロープ、ＰＣ鋼線など太径の製
品においては、熱間圧延線材を最終製品径にまで伸線加
工する。したがって、伸線加工性を高めて冷間加工度を
大きくできれば、これまでよりも強度の高い製品を得る
ことが可能となるので、軽量化が期待できる。このた
め、太径の製品においても、冷間での伸線加工性に優れ
た線材に対する要求が大きくなっている。In the case of products having a large diameter such as a wire rope and a PC steel wire, a hot-rolled wire is drawn to a final product diameter. Therefore, if the degree of cold working can be increased by increasing the wire drawing workability, it is possible to obtain a product having higher strength than before, and thus a reduction in weight can be expected. For this reason, even for a product having a large diameter, a demand for a wire rod having excellent cold-drawability is increasing.
【０００７】上記した近年の産業界からの要望に対し
て、偏析やミクロ組織を制御して線材の伸線加工性を高
める技術が提案されている。[0007] In response to the above-mentioned demands from the industry in recent years, there has been proposed a technique of controlling segregation and microstructure to enhance the wire drawing workability of a wire.
【０００８】例えば、特公平７−１１０６０号公報に
は、線材のＭｎの偏析を制御する「伸線加工性のすぐれ
た高強度鋼線材」が開示されている。しかし、この公報
で提案された技術は、線材におけるＭｎの偏析ピーク幅
を小さくするために、鋳片サイズを大きくとって圧減
比を高める、中心偏析を改善するために鋳造時の溶鋼
過熱度を低めとする、鋳型内電磁撹拌を行う、凝固
末期に鋳片に圧下をかける、鋳片を均熱炉中で加熱し
偏析元素を拡散させる、などの特殊な処理を必要とす
る。このため、線材の製造工程や製造設備が異なる場合
には、必ずしも適用できないものであるし、たとえ適用
できたとしても製造コストが嵩むものであった。更に、
Ｍｎの偏析を制御しても、熱間圧延した線材の絞りの向
上には寄与するが、前記した中間処理としてのパテンテ
ィングを省略するには不十分であった。For example, Japanese Patent Publication No. 7-11060 discloses a "high-strength steel wire excellent in wire drawing workability" for controlling the segregation of Mn in the wire. However, the technique proposed in this publication is to increase the pressure reduction ratio by increasing the slab size in order to reduce the Mn segregation peak width in the wire, and to increase the degree of superheat of molten steel during casting in order to improve center segregation. Special treatments such as lowering the temperature, performing electromagnetic stirring in the mold, applying pressure to the slab at the end of solidification, and heating the slab in a soaking furnace to diffuse segregated elements are required. For this reason, when the manufacturing process or manufacturing equipment of a wire is different, it cannot necessarily be applied, and even if it can be applied, the manufacturing cost increases. Furthermore,
Controlling the segregation of Mn also contributes to the improvement of the drawing of the hot-rolled wire rod, but was insufficient to omit the patenting as the intermediate treatment described above.
【０００９】特開平６−７３５０２号公報には、２段変
態により得られた上部ベイナイト組織が面積率で８０％
である「伸線加工性に優れた高炭素鋼線材または鋼線」
が開示されている。しかし、２段変態により上部ベイナ
イト組織を得るためには、熱間圧延後に線材を直接溶融
塩に浸漬して冷却することが必要で、この処理のための
特殊な設備を設ける必要があり、設備コストの上昇を招
く。更に、上記のような溶融塩を媒体とした冷却を行う
と、それが線材の表面に付着し、付着した塩を除去する
工程が必要になり、製造コストの一層の上昇をきたす。Japanese Unexamined Patent Publication (Kokai) No. 6-73502 discloses that the upper bainite structure obtained by the two-stage transformation has an area ratio of 80%.
"High carbon steel wire or steel wire with excellent wire drawability"
Is disclosed. However, in order to obtain an upper bainite structure by two-stage transformation, it is necessary to immerse the wire directly in molten salt after hot rolling and cool it, and it is necessary to provide special equipment for this treatment. This leads to higher costs. Further, when the above-mentioned cooling using the molten salt as a medium is performed, the cooling salt adheres to the surface of the wire, and a step of removing the attached salt is required, which further increases the production cost.
【００１０】特公平７−１１０６０号公報や特開平６−
７３５０２号公報で提案された技術によれば、一応は伸
線加工性に優れた線材を得ることができる。しかし、既
に述べたように、設備コストや製造コストが嵩むという
大きな問題があった。[0010] Japanese Patent Publication No. 7-11060 and Japanese Unexamined Patent Publication No.
According to the technique proposed in Japanese Patent No. 73502, a wire rod excellent in wire drawing workability can be obtained. However, as described above, there is a major problem that equipment costs and manufacturing costs increase.
【００１１】[0011]
【発明が解決しようとする課題】本発明は、上記現状に
鑑みなされたもので、その目的は、ワイヤロープ、ＰＣ
鋼線、ビードワイヤー、スチールコードなどの用途に好
適な伸線加工性に優れた高炭素鋼線材、なかでも前記し
た真歪量で２．６０を超えて伸線加工しても断線を生ず
ることがない高炭素鋼線材を廉価に提供することであ
る。SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object the object of the present invention to provide a wire rope, a PC,
High-carbon steel wire with excellent drawability suitable for applications such as steel wire, bead wire, and steel cord. Above all, the wire may break even if it is drawn with a true strain of more than 2.60. The aim is to provide a low-carbon steel wire rod without any cost.
【００１２】[0012]
【課題を解決するための手段】本発明の要旨は、下記
（１）及び（２）に示す伸線加工性に優れた線材にあ
る。SUMMARY OF THE INVENTION The gist of the present invention resides in a wire excellent in wire drawing work shown in the following (1) and (2).
【００１３】（１）重量％で、Ｃ：０．７〜１．１％、
Ｓｉ：０．１〜１．５％、Ｍｎ：０．２〜１．０％、Ａ
ｌ：０．００１〜０．００３％、Ｃｒ：１．０％以下、
Ｎ：０．００６％以下、Ｃｕ：１．０％以下、Ｎｉ：
２．０％以下、Ｍｏ：０．５％以下、Ｃｏ：４．０％以
下、Ｖ：０．４％以下、Ｎｂ：０．１％以下、Ｔｉ：
０．１％以下、Ｂ：０．００５％以下、Ｐ：０．０５％
以下、Ｓ：０．０５％以下、希土類元素：０．１０％以
下、Ｃａ：０．０１％以下、Ｍｇ：０．０１％以下を含
有し、残部はＦｅ及び不可避不純物からなる鋼線材の横
断面において、外周から前記鋼線材の半径の１／５０の
深さの位置までの領域におけるＣ含有量の平均値が０．
６〜０．９×Ｃ％（但し、Ｃは鋼線材のＣ含有量）であ
ることを特徴とする伸線加工性に優れた鋼線材。(1) C: 0.7 to 1.1% by weight,
Si: 0.1 to 1.5%, Mn: 0.2 to 1.0%, A
l: 0.001 to 0.003%, Cr: 1.0% or less ,
N : 0.006% or less, Cu: 1.0% or less, Ni:
2.0% or less, Mo: 0.5% or less, Co: 4.0% or less, V: 0.4% or less, Nb: 0.1% or less, Ti:
0.1% or less, B: 0.005% or less, P: 0.05%
Hereinafter, S: 0.05% or less, rare earth element: 0.10% or less, Ca: 0.01% or less, Mg: 0.01% or less, the balance being a crossing of a steel wire rod composed of Fe and unavoidable impurities. In the surface, the average value of the C content in a region from the outer periphery to a position at a depth of 1/50 of the radius of the steel wire rod is 0.
A steel wire excellent in wire drawability characterized by being 6 to 0.9 × C% (where C is the C content of the steel wire).
【００１４】（２）重量％で、Ｃ：０．７〜１．１％、
Ｓｉ：０．１〜１．５％、Ｍｎ：０．２〜１．０％、Ａ
ｌ：０．００１〜０．００３％、Ｃｒ：１．０％以下、
Ｎ：０．００６％以下、Ｃｕ：１．０％以下、Ｎｉ：
２．０％以下、Ｍｏ：０．５％以下、Ｗ：０．５％以
下、Ｃｏ：４．０％以下、Ｖ：０．４％以下、Ｎｂ：
０．１％以下、Ｔｉ：０．１％以下、Ｚｒ：０．１％以
下、Ｂ：０．００５％以下、Ｐ：０．０５％以下、Ｓ：
０．０５％以下、希土類元素：０．１０％以下、Ｃａ：
０．０１％以下、Ｍｇ：０．０１％以下を含有し、残部
はＦｅ及び不可避不純物からなる鋼線材の横断面におい
て、外周から前記鋼線材の半径の１／５０の深さの位置
までの領域におけるＣ含有量の平均値が０．６〜０．９
×Ｃ％（但し、Ｃは鋼線材のＣ含有量）であることを特
徴とする伸線加工性に優れた鋼線材。(2) C: 0.7 to 1.1% by weight,
Si: 0.1 to 1.5%, Mn: 0.2 to 1.0%, A
l: 0.001 to 0.003%, Cr: 1.0% or less ,
N : 0.006% or less, Cu: 1.0% or less, Ni:
2.0% or less, Mo: 0.5% or less, W: 0.5% or less, Co: 4.0% or less, V: 0.4% or less, Nb:
0.1% or less, Ti: 0.1% or less, Zr: 0.1% or less, B: 0.005% or less, P: 0.05% or less, S:
0.05% or less, rare earth element: 0.10% or less, Ca:
0.01% or less, Mg: 0.01% or less, with the balance being from the outer periphery to a position at a depth of 1/50 of the radius of the steel wire in the cross section of the steel wire made of Fe and inevitable impurities. The average value of the C content in the region is 0.6 to 0.9.
× C% (where C is the C content of the steel wire), wherein the steel wire is excellent in wire drawability.
【００１５】なお、本発明でいう線材の「横断面」と
は、線材の圧延方向に垂直に切断した面をいう。又、
「線材の外周から前記線材の半径の１／５０の深さの位
置までの領域におけるＣ含有量の平均値」とは、例えば
波長分散型の電子線マイクロアナライザーを用いて線材
外周部（表層部近傍）のＣ含有量の線分析を行った場合
の、外周から半径の４／２５０、３／２５０、２／２５
０及び１／２５０の深さの位置におけるＣ含有量の平均
値を指す。The "cross-section" of the wire in the present invention refers to a surface cut perpendicular to the rolling direction of the wire. or,
The “average value of the C content in a region from the outer periphery of the wire to a position at a depth of 1/50 of the radius of the wire” means, for example, the outer periphery of the wire (surface layer portion) using a wavelength-dispersive electron beam microanalyzer. 4/250, 3/250, and 2/25 of the radius from the outer circumference when a line analysis of the C content was performed.
It indicates the average value of the C content at the positions of 0 and 1/250 depth.
【００１６】本発明者らは、熱間圧延した高炭素鋼線材
の組織、なかでも表層部組織が伸線加工性に及ぼす影響
について調査・研究を重ね、その結果、下記の知見を得
た。The present inventors have repeatedly conducted investigations and studies on the effect of the structure of the hot-rolled high carbon steel wire rod, particularly the surface layer structure, on the drawability. As a result, the following findings were obtained.
【００１７】（ａ）曲げ加工や鍛造の場合と異なり冷間
での伸線加工は多段、且つ、大きな加工度で行われるた
め、表層部に軟質なフェライト組織が存在すれば却って
加工性が低下し、伸線加工中に断線を生じ易い。つま
り、鋼材の表層部に軟質なフェライト組織を存在させる
ことにより、冷間での曲げ加工性や鍛造性を高めようと
する特開昭５６−５５５２０号公報や特開平８−１０９
４３７号公報で提案されている技術は、これを伸線加工
に適用しても、伸線加工性を高めることはできない。し
かし、線材の表層部（外周近傍）の硬度を、母材部硬度
（以下、中心部の硬度という）より低くすれば冷間での
伸線加工時の変形抵抗が減少するので、伸線加工性を高
めることができる。(A) Unlike the bending and forging, the cold drawing is performed in multiple steps and with a large degree of work. Therefore, if a soft ferrite structure exists in the surface layer, workability is rather deteriorated. However, disconnection is likely to occur during wire drawing. That is, JP-A-56-55520 and JP-A-8-109 attempt to enhance cold workability and forgeability by having a soft ferrite structure in the surface layer of a steel material.
Even if the technology proposed in Japanese Patent No. 437 is applied to wire drawing, the wire drawing workability cannot be improved. However, if the hardness of the surface layer (near the outer periphery) of the wire is lower than the hardness of the base material (hereinafter referred to as the hardness of the central portion), the deformation resistance during cold wire drawing decreases, so that the wire drawing is performed. Can be enhanced.
【００１８】（ｂ）線材の外周近傍の硬度を中心部の硬
度より下げるためには、外周近傍の炭素含有量を低下さ
せれば良い。(B) In order to lower the hardness near the outer periphery of the wire than the hardness at the center, the carbon content near the outer periphery may be reduced.
【００１９】（ｃ）外周近傍の炭素含有量の平均値を
０．６重量％以上にすれば、組織中に初析フェライトが
析出することがないので、冷間伸線時の限界加工度を高
めることができる。(C) When the average value of the carbon content in the vicinity of the outer periphery is set to 0.6% by weight or more, proeutectoid ferrite does not precipitate in the structure. Can be enhanced.
【００２０】（ｄ）上記（ａ）〜（ｃ）から、外周近傍
の炭素含有量が適正な範囲にあれば、伸線加工性を高め
ることが可能である。そして、これによって冷間伸線に
用いるダイス寿命を向上させることもできる。(D) From the above (a) to (c), if the carbon content in the vicinity of the outer periphery is in an appropriate range, it is possible to enhance the wire drawing workability. Thus, the life of a die used for cold drawing can be improved.
【００２１】本発明は、上記の知見に基づいて完成され
たものである。The present invention has been completed based on the above findings.
【００２２】[0022]
【発明の実施の形態】以下、本発明について詳しく説明
する。なお、化学成分の含有量の「％」は「重量％」を
意味する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail. In addition, “%” of the content of the chemical component means “% by weight”.
【００２３】（Ａ）線材の化学組成
Ｃ：０．７〜１．１％
Ｃは、強度を確保するのに有効な元素である。しかし、
その含有量が０．７％未満の場合にはワイヤロープ、Ｐ
Ｃ鋼線、ビードワイヤー、スチールコードなどの最終製
品に安定して高い強度を付与させることが困難である。
一方、Ｃの含有量が多すぎると鋼材が硬質化して冷間加
工性の低下を招く。特に、Ｃ含有量が１．１％を超える
と、線材が硬質化するばかりでなく、初析セメンタイト
（つまり、旧オーステナイト粒界に沿うセメンタイト）
の生成防止が困難になって伸線加工性が低下する。この
ため、外周近傍の炭素含有量を後述する範囲に制御して
も、真歪量で２．６０を超えるような大きな加工度で伸
線すれば断線が多発する。したがって、Ｃの含有量を
０．７〜１．１％とした。(A) Chemical composition C of the wire rod: 0.7 to 1.1% C is an element effective for securing the strength. But,
If the content is less than 0.7%, wire rope, P
It is difficult to stably give high strength to final products such as C steel wire, bead wire, and steel cord.
On the other hand, if the content of C is too large, the steel material becomes hard and causes a reduction in cold workability. In particular, when the C content exceeds 1.1%, not only the wire becomes hardened, but also proeutectoid cementite (that is, cementite along the prior austenite grain boundary).
It is difficult to prevent the formation of manganese, and the wire drawing workability is reduced. For this reason, even if the carbon content in the vicinity of the outer periphery is controlled to a range described later, disconnection occurs frequently if the wire is drawn at a large working ratio such that the true strain exceeds 2.60. Therefore, the content of C is set to 0.7 to 1.1%.
【００２４】Ｓｉ：０．１〜１．５％
Ｓｉは、強度を高めるのに有効な元素である。更に、脱
酸剤として必要な元素でもある。しかし、その含有量が
０．１％未満では添加効果に乏しく、一方、１．５％を
超えると伸線加工での限界加工度が低下し、真歪量で
２．６０を超えるような大きな加工度で伸線すれば断線
が多発する。したがって、Ｓｉ含有量を０．１〜１．５
％とした。Si: 0.1-1.5% Si is an effective element for increasing the strength. Further, it is an element necessary as a deoxidizing agent. However, if the content is less than 0.1%, the effect of addition is poor. On the other hand, if the content exceeds 1.5%, the critical workability in wire drawing decreases, and the true strain exceeds 2.60. If the wire is drawn at the degree of processing, disconnection frequently occurs. Therefore, the Si content is set to 0.1 to 1.5.
%.
【００２５】Ｍｎ：０．２〜１．０％
Ｍｎは、強度を高める作用に加えて、鋼中のＳをＭｎＳ
として固定して熱間脆性を防止する作用を有する。しか
し、その含有量が０．２％未満では前記の効果が得難
い。一方、Ｍｎは偏析しやすい元素であり、１．０％を
超えると特に線材の中心部に偏析し、その偏析部にはマ
ルテンサイトやベイナイトが生成するので、伸線加工性
が低下してしまう。したがって、Ｍｎ含有量を０．２〜
１．０％とした。Mn: 0.2-1.0% In addition to the effect of increasing the strength, Mn reduces S in steel to MnS
And has the effect of preventing hot brittleness. However, if the content is less than 0.2%, it is difficult to obtain the above effects. On the other hand, Mn is an element that is easily segregated. If it exceeds 1.0%, Mn is segregated particularly at the center of the wire, and martensite and bainite are generated at the segregated portion, so that wire drawing workability is reduced. . Therefore, the Mn content is 0.2 to
1.0%.
【００２６】Ｃｒ：１．０％以下
Ｃｒは添加しなくても良い。添加すれば、パーライトの
ラメラ間隔を小さくして圧延後及びパテンティング後の
強度を高める作用を有する。又、伸線加工を初めとする
冷間加工時の加工硬化率を高める働きがあるので、Ｃｒ
の添加によって比較的低い加工率でも高強度を得ること
ができる。こうした効果を確実に得るには、Ｃｒは０．
１％以上の含有量とすることが好ましい。一方、Ｃｒを
過剰に添加するとパーライト変態が終了するまでの時間
が長くなり、熱間圧延後の線材の中心部にマルテンサイ
トやベイナイトが生成するため、伸線加工中の断線頻度
が増加する。特に、Ｃｒ含有量が１．０％を超えると、
真歪量で２．６０を超えるような大きな加工度で伸線す
れば断線が多発する。したがって、Ｃｒの含有量を１．
０％以下とした。Cr: 1.0% or less Cr may not be added. If added, it has the effect of reducing the lamella spacing of pearlite and increasing the strength after rolling and after patenting. Also, since it has the function of increasing the work hardening rate during cold working such as wire drawing,
High strength can be obtained even at a relatively low processing rate by adding. To ensure such an effect, the content of Cr should be set to 0.1.
The content is preferably 1% or more. On the other hand, if Cr is added excessively, the time required for the pearlite transformation to end is increased, and martensite and bainite are generated at the center of the wire after hot rolling, so that the frequency of breakage during wire drawing increases. In particular, when the Cr content exceeds 1.0%,
If the wire is drawn with a large working degree such that the true strain exceeds 2.60, disconnection frequently occurs. Therefore, if the content of Cr is 1.
0% or less.
【００２７】Ａｌ：０．００１〜０．００３％
Ａｌの含有量が０．０５％を超えると、Ａｌ２Ｏ３を主
成分とする酸化物系介在物が粗大になり、伸線加工中に
断線が多発する。特に、最終製品の線径が直径で０．５
ｍｍ以下の場合は、Ａｌ２Ｏ３を主成分とする酸化物系
介在物が微細であっても、最終伸線時に断線する原因と
なる。このため、線材のＡｌ含有量を０．００１〜０．
００３％とした。 Al: 0.001 to 0.003% When the content of Al exceeds 0.05%, oxide inclusions containing Al 2 O 3 as a main component become coarse, and during the wire drawing. Disconnection occurs frequently. In particular, 0.5 at a linear diameter of the final product diameter
In the case of not more than mm, even if the oxide-based inclusions containing Al 2 O 3 as a main component are fine, they may cause disconnection at the time of final drawing. For this reason , the Al content of the wire is set to 0.001 to 0.1.
003%.
【００２８】Ｎ：０．００６％以下
Ｎは、冷間での伸線加工中に転位に固着し、鋼線の強度
を上昇させる一方、伸線加工性を低下させてしまう。し
かし、このＮの悪影響はその含有量を０．００６％以下
にすることで防止できる。したがって、Ｎ含有量を０．
００６％以下とした。N: 0.006% or less N adheres to dislocations during cold drawing and increases the strength of the steel wire, but decreases the drawability. However, this adverse effect of N can be prevented by reducing the content to 0.006% or less. Therefore, the N content is set to 0.1.
006% or less.
【００２９】Ｃｕ：１．０％以下
Ｃｕは添加しなくてもよい。添加すれば耐食性を高める
作用がある。この効果を確実に得るには、Ｃｕは０．０
５％以上の含有量とすることが好ましい。しかし、その
含有量が１．０％を超えると結晶粒界に偏析して鋼塊の
分塊圧延や線材の熱間圧延など熱間加工時における割れ
や疵の発生が顕著になる。したがって、Ｃｕの含有量を
１．０％以下とした。Cu: 1.0% or less Cu may not be added. If added, it has the effect of increasing corrosion resistance. To ensure this effect, Cu should be 0.0
Preferably, the content is 5% or more. However, if the content exceeds 1.0%, segregation at crystal grain boundaries causes cracks and flaws to be noticeable during hot working such as bulk rolling of steel ingots and hot rolling of wires. Therefore, the content of Cu is set to 1.0% or less.
【００３０】Ｎｉ：２．０％以下
Ｎｉは添加しなくてもよい。添加すれば、フェライト中
に固溶してフェライトの靭性を向上させる効果を発揮す
る。この効果を確実に得るには、Ｎｉは０．２％以上の
含有量とすることが好ましい。しかし、その含有量が
２．０％を超えると、焼入れ性が高くなり過ぎてマルテ
ンサイトが生成し易くなり伸線加工性が劣化する。した
がって、Ｎｉの含有量を２．０％以下とした。Ni: 2.0% or less Ni may not be added. If added, it has the effect of forming a solid solution in the ferrite and improving the toughness of the ferrite. To ensure this effect, the content of Ni is preferably set to 0.2% or more. However, if the content exceeds 2.0%, the quenchability becomes too high, so that martensite is easily formed and the wire drawing workability is deteriorated. Therefore, the content of Ni is set to 2.0% or less.
【００３１】Ｍｏ：０．５％以下
Ｍｏは添加しなくてもよい。添加すれば、熱処理で微細
な炭化物として析出し強度と疲労特性を高める作用があ
る。この効果を確実に得るには、Ｍｏは０．０５％以上
の含有量とすることが好ましい。一方、０．５％を超え
て含有させても前記の効果は飽和し、コストが嵩むばか
りである。したがって、Ｍｏの含有量を０．５％以下と
した。Mo: 0.5% or less Mo may not be added. If added, it precipitates as fine carbides by heat treatment and has the effect of increasing strength and fatigue properties. To ensure this effect, it is preferable that the content of Mo be 0.05% or more. On the other hand, if the content exceeds 0.5%, the above effect is saturated and the cost is increased. Therefore, the content of Mo is set to 0.5% or less.
【００３２】Ｗ：０．５％以下
Ｗは添加しなくてもよい。添加すれば、熱処理で微細な
炭化物として析出し強度を高める効果がある。又、Ｗは
耐食性の向上にも有効に作用する。これらの効果を確実
に得るには、Ｗは０．０５％以上の含有量とすることが
好ましい。一方、０．５％を超えて含有させても前記の
効果は飽和し、コストが嵩むばかりである。したがっ
て、Ｗの含有量を０．５％以下とした。W: 0.5% or less W may not be added. If added, it has the effect of precipitating as fine carbides by heat treatment and increasing the strength. W also effectively acts on improving corrosion resistance. In order to surely obtain these effects, the content of W is preferably set to 0.05% or more. On the other hand, if the content exceeds 0.5%, the above effect is saturated and the cost is increased. Therefore, the content of W is set to 0.5% or less.
【００３３】Ｃｏ：４．０％以下
Ｃｏは添加しなくても良い。添加すれば、初析セメンタ
イトの析出を防止し、更にパーライトを微細化して強度
を高める作用を有する。この効果を確実に得るには、Ｃ
ｏは０．２％以上の含有量とすることが好ましい。しか
し、４．０％を超えて含有させても前記の効果は飽和
し、コストが嵩むばかりである。したがって、Ｃｏの含
有量を４．０％以下とした。Co: 4.0% or less Co may not be added. When added, it has the effect of preventing precipitation of proeutectoid cementite and further reducing the pearlite to increase the strength. To ensure this effect, C
It is preferable that the content of o is 0.2% or more. However, even if the content exceeds 4.0%, the above effect is saturated and the cost is increased. Therefore, the content of Co is set to 4.0% or less.
【００３４】Ｖ：０．４％以下
Ｖは添加しなくてもよい。添加すれば、オーステナイト
結晶粒を微細化させ、延性及び靭性を高める作用を有す
る。この効果を確実に得るには、Ｖは０．０５％以上の
含有量とすることが好ましい。しかし、０．４％を超え
て含有させても前記の効果は飽和し、コストが嵩むばか
りである。したがって、Ｖの含有量を０．４％以下とし
た。V: 0.4% or less V may not be added. If added, it has the effect of refining austenite crystal grains and increasing ductility and toughness. In order to surely obtain this effect, it is preferable that the content of V is 0.05% or more. However, even if the content exceeds 0.4%, the above effect is saturated and the cost is increased. Therefore, the content of V is set to 0.4 % or less.
【００３５】Ｎｂ：０．１％以下
Ｎｂは添加しなくてもよい。添加すれば、オーステナイ
ト結晶粒を微細化させ、延性及び靭性を高める作用を有
する。この効果を確実に得るには、Ｎｂは０．００１％
以上の含有量とすることが好ましい。しかし、０．１％
を超えて含有させても前記の効果は飽和し、コストが嵩
むばかりである。したがって、Ｎｂの含有量を０．１％
以下とした。Nb: 0.1% or less Nb may not be added. If added, it has the effect of refining austenite crystal grains and increasing ductility and toughness. To ensure this effect, Nb is 0.001%
It is preferable to set the content as described above. But 0.1%
If the content exceeds the above range, the above effect is saturated and the cost is increased. Therefore, the content of Nb is 0.1%
The following was set.
【００３６】Ｔｉ：０．１％以下
Ｔｉは添加しなくてもよい。添加すれば、オーステナイ
ト結晶粒を微細化させ、延性及び靭性を高める作用を有
する。この効果を確実に得るには、Ｔｉは０．０１％以
上の含有量とすることが好ましい。しかし、０．１％を
超えて含有させても前記の効果は飽和し、コストが嵩む
ばかりである。したがって、Ｔｉの含有量を０．１％以
下とした。Ti: 0.1% or less Ti need not be added. If added, it has the effect of refining austenite crystal grains and increasing ductility and toughness. To ensure this effect, the content of Ti is preferably set to 0.01% or more. However, even if the content exceeds 0.1%, the above effect is saturated and the cost is increased. Therefore, the content of Ti is set to 0.1% or less.
【００３７】Ｚｒ：０．１％以下
Ｚｒは添加しなくてもよい。添加すれば、オーステナイ
ト結晶粒を微細化させ、延性及び靭性を高める作用を有
する。この効果を確実に得るには、Ｚｒは０．０１％以
上の含有量とすることが好ましい。しかし、０．１％を
超えて含有させても前記の効果は飽和し、コストが嵩む
ばかりである。したがって、Ｚｒの含有量を０．１％以
下とした。Zr: 0.1% or less Zr may not be added. If added, it has the effect of refining austenite crystal grains and increasing ductility and toughness. In order to surely obtain this effect, the content of Zr is preferably set to 0.01% or more. However, even if the content exceeds 0.1%, the above effect is saturated and the cost is increased. Therefore, the content of Zr is set to 0.1% or less.
【００３８】Ｂ：０．００５％以下
Ｂは添加しなくてもよい。添加すれば、パーライト中の
セメンタイトの成長を促進させて線材の延性を高める作
用を有する。この効果を確実に得るには、Ｂは０．００
０３％以上の含有量とすることが好ましい。しかし、そ
の含有量が０．００５％を超えると、熱間や温間での加
工時に割れが生じ易くなる。したがって、Ｂの含有量を
０．００５％以下とした。B: 0.005% or less B may not be added. If added, it has the effect of promoting the growth of cementite in pearlite and increasing the ductility of the wire. To ensure this effect, B is 0.00
The content is preferably at least 03%. However, if the content exceeds 0.005%, cracks are likely to occur during hot or warm working. Therefore, the content of B is set to 0.005% or less.
【００３９】Ｐ：０．０５％以下
Ｐは伸線加工性を低下させてしまう。特にその含有量が
０．０５％を超えると伸線加工性の低下が著しくなる。
したがって、Ｐの含有量を０．０５％以下とした。P: 0.05% or less P lowers the drawability. In particular, when the content exceeds 0.05%, the wire drawing workability is significantly reduced.
Therefore, the content of P is set to 0.05% or less.
【００４０】Ｓ：０．０５％以下
Ｓは伸線加工性を低下させてしまう。特にその含有量が
０．０５％を超えると伸線加工性の低下が著しくなる。
したがって、Ｓの含有量を０．０５％以下とした。S: 0.05% or less S reduces the drawability. In particular, when the content exceeds 0.05%, the wire drawing workability is significantly reduced.
Therefore, the content of S is set to 0.05% or less.
【００４１】希土類元素：０．１０％以下
希土類元素は添加しなくてもよい。添加すれば、熱間加
工性を高める作用を有する。この効果を確実に得るに
は、希土類元素は０．００２％以上の含有量とすること
が好ましい。しかし、希土類元素を０．１０％を超えて
含有させても前記の効果は飽和し、コストが嵩むばかり
である。したがって、希土類元素の含有量を０．１０％
以下とした。なお、本発明でいう「希土類元素の含有
量」は、「希土類元素の合計の含有量」を指す。Rare earth element: 0.10% or less Rare earth element need not be added. If added, it has the effect of increasing hot workability. To ensure this effect, the content of the rare earth element is preferably 0.002% or more. However, even if the rare earth element is contained in an amount exceeding 0.10%, the above effect is saturated and the cost is increased. Therefore, the content of the rare earth element is 0.10%
The following was set. The “content of the rare earth element” in the present invention indicates “the total content of the rare earth element”.
【００４２】Ｃａ：０．０１％以下
Ｃａは添加しなくてもよい。添加すれば、熱間加工性を
高める作用を有する。この効果を確実に得るには、Ｃａ
は０．０００５％以上の含有量とすることが好ましい。
しかし、Ｃａを０．０１％を超えて含有させても前記の
効果は飽和し、コストが嵩むばかりである。したがっ
て、Ｃａの含有量を０．０１％以下とした。Ca: 0.01% or less Ca may not be added. If added, it has the effect of increasing hot workability. To ensure this effect, Ca
Is preferably 0.0005% or more.
However, even if Ca is contained in an amount exceeding 0.01%, the above-mentioned effect is saturated, and the cost is increased. Therefore, the content of Ca is set to 0.01% or less.
【００４３】Ｍｇ：０．０１％以下
Ｍｇは添加しなくてもよい。添加すれば、熱間加工性を
高める作用を有する。この効果を確実に得るには、Ｍｇ
は０．０００５％以上の含有量とすることが好ましい。
しかし、Ｍｇを０．０１％を超えて含有させても前記の
効果は飽和し、コストが嵩むばかりである。したがっ
て、Ｍｇの含有量を０．０１％以下とした。Mg: 0.01% or less Mg need not be added. If added, it has the effect of increasing hot workability. To ensure this effect, use Mg
Is preferably 0.0005% or more.
However, even if Mg is contained in an amount exceeding 0.01%, the above effect is saturated, and the cost is increased. Therefore, the content of Mg is set to 0.01% or less.
【００４４】（Ｂ）線材の横断面における炭素含有量分
布
本発明においては、線材の外周から前記線材の半径の１
／５０の深さの位置までの領域におけるＣ含有量の平均
値を０．６〜０．９×Ｃ％に規定する。これは、下記の
理由による。(B) Carbon Content Distribution in the Cross Section of the Wire In the present invention, the radius of the wire from the outer periphery of the wire is 1%.
The average value of the C content in the region up to the depth of / 50 is defined as 0.6 to 0.9 × C%. This is for the following reason.
【００４５】線材を冷間で伸線加工する際の変形は、外
周部つまり表層部に近い方が大きく、特に横断面におい
て、外周から半径の１／５０の深さの領域での変形が大
きい。本発明は、前記の領域の硬度を中心部の硬度より
低くして冷間での伸線加工時の変形抵抗を減少させ、伸
線加工性を高めることを大きな特徴とする。この場合、
前記領域におけるＣ含有量の平均値が０．９×Ｃ％を超
えれば、冷間伸線加工時の変形抵抗の減少は小さく、伸
線加工性を高めることができない。なお、「Ｃ」が「線
材のＣ含有量」を指すことは既に述べたとおりであり、
例えば、とりべ分析値を意味する。一方、前記領域にお
けるＣ含有量の平均値が０．６％未満であれば、初析フ
ェライトが析出し、伸線加工時にこの軟質な初析フェラ
イトに変形応力が集中するため限界加工度が低下するの
で、真歪量で２．６０を超えるような大きな加工度で伸
線すれば断線が多発する。したがって、線材の外周から
前記線材の半径の１／５０の深さの位置までの領域にお
けるＣ含有量の平均値を０．６〜０．９×Ｃ％とした。The deformation at the time of cold drawing of the wire is large near the outer periphery, that is, closer to the surface layer. In particular, in the cross section, the deformation at a depth of 1/50 of the radius from the outer periphery is large. . The present invention is characterized in that the hardness of the above-mentioned region is made lower than the hardness of the central portion to reduce the deformation resistance at the time of cold drawing and to enhance the drawability. in this case,
If the average value of the C content in the region exceeds 0.9 × C%, the decrease in deformation resistance during cold drawing is small, and the drawing workability cannot be improved. As described above, “C” indicates “C content of the wire rod”.
For example, it means a ladle analysis value. On the other hand, if the average value of the C content in the region is less than 0.6%, pro-eutectoid ferrite precipitates and the deformation stress concentrates on this soft eutectoid ferrite during wire drawing, so that the critical workability decreases. Therefore, if the wire is drawn with a large working degree such that the true strain exceeds 2.60, disconnection frequently occurs. Therefore, the average value of the C content in the region from the outer periphery of the wire to a position at a depth of 1/50 of the radius of the wire is set to 0.6 to 0.9 × C%.
【００４６】なお、「線材の外周から前記線材の半径の
１／５０の深さの位置までの領域におけるＣ含有量の平
均値」が、例えば波長分散型の電子線マイクロアナライ
ザーを用いて線材外周部（表層部近傍）のＣ含有量の線
分析を行った場合の、外周から半径の４／２５０、３／
２５０、２／２５０及び１／２５０の深さの位置におけ
るＣ含有量の平均値を指すことは既に述べたとおりであ
る。The "average value of the C content in the region from the outer periphery of the wire to a position at a depth of 1/50 of the radius of the wire" is calculated, for example, using a wavelength-dispersive electron beam microanalyzer. When the line analysis of the C content of the part (near the surface layer part) was performed, 4/250, 3 /
As described above, it indicates the average value of the C content at the depths of 250, 2/250, and 1/250.
【００４７】線材の外周から前記線材の半径の１／５０
の深さの位置までの領域におけるＣ含有量の平均値を
０．６〜０．９×Ｃ％とするには、例えば脱炭層がほと
んどないビレットを天然ガス（主成分はメタン（ＣＨ
4 ））を燃料とする加熱炉で加熱する場合、１０５０〜
１１００℃の温度に保持した炉内に前記のビレットを装
入して３０〜４０分保持し、圧延仕上げ温度を８３０〜
８７０℃として熱間圧延した後、５〜１０℃／秒の冷却
速度で５００℃以下の温度まで冷却すれば良い。又、ビ
レットに脱炭層がある場合には、その度合いに応じて炉
の温度と在炉時間を変更すれば良い。1/50 of the radius of the wire from the outer circumference of the wire
In order to make the average value of the C content in the region up to the position of the depth of 0.6 to 0.9 × C%, for example, a billet having almost no decarburized layer is converted into natural gas (main component is methane (CH 2
4 ) When heating in a heating furnace using fuel,
The billet was charged into a furnace maintained at a temperature of 1100 ° C. and maintained for 30 to 40 minutes.
After hot rolling at 870 ° C., it may be cooled to a temperature of 500 ° C. or lower at a cooling rate of 5 to 10 ° C./sec. When the billet has a decarburized layer, the temperature of the furnace and the time in the furnace may be changed according to the degree of the decarburized layer.
【００４８】前記（Ａ）項に記載の化学組成と本（Ｂ）
項に記載の炭素含有量の分布を有する線材は、通常の方
法で伸線加工が施され、次いで、調質処理やブルーイン
グ処理が施されてワイヤロープ、ＰＣ鋼線などの最終製
品に仕上げられる。あるいは、通常の方法で伸線加工が
施され、次いで、最終熱処理と最終伸線が施されてビー
ドワイヤーやスチールコード用の鋼線に仕上げられる。The chemical composition described in the above (A) and the present (B)
The wire having the distribution of the carbon content described in the section is subjected to wire drawing in the usual way, and then subjected to tempering and bluing to finish the final product such as wire rope and PC steel wire. Can be Alternatively, wire drawing is performed in a usual manner, and then final heat treatment and final wire drawing are performed to finish a bead wire or a steel wire for a steel cord.
【００４９】以下、実施例により本発明を詳しく説明す
る。Hereinafter, the present invention will be described in detail with reference to examples.
【００５０】表１に示す化学組成を有する鋼Ｂ〜Ｍを１
５０ｋｇ真空炉を用いて溶製した。表１における鋼Ｂ、
Ｃ、Ｅ、Ｇ、Ｉ、Ｌ及びＭは化学組成が本発明で規定す
る含有量の範囲内にある本発明例である。一方、鋼Ｄ、
Ｆ、Ｈ、Ｊ及びＫは成分のいずれかが本発明で規定する
含有量の範囲から外れた比較例である。The steels B to M having the chemical compositions shown in Table 1 were
It was melted using a 50 kg vacuum furnace. Steel B in Table 1 ,
C, E, G, I, L and M are examples of the present invention in which the chemical composition is within the range of the content specified in the present invention. On the other hand, steel D,
F, H, J and K are comparative examples in which any one of the components is out of the range of the content specified in the present invention.
【００５１】[0051]
【表１】 [Table 1]
【００５２】次いで、これらの鋼を通常の方法で熱間鍛
造して直径６０ｍｍの丸棒にし、次いで、直径５０ｍｍ
まで機械研削して脱炭層を完全に除去した。この後、上
記の直径５０ｍｍの丸棒を６等分し、加熱炉中の雰囲気
を制御しながら１０５０℃で３０分間加熱し、通常の方
法で熱間圧延し、直径５．５ｍｍ又は１０ｍｍの線材に
した。なお、熱間圧延した各線材はパーライト組織を主
とするものであった。Next, these steels were hot-forged in a usual manner into round bars having a diameter of 60 mm,
The decarburized layer was completely removed by mechanical grinding until completely. Thereafter, the above-mentioned round bar having a diameter of 50 mm is divided into six equal parts, heated at 1050 ° C. for 30 minutes while controlling the atmosphere in a heating furnace, and hot-rolled by a usual method to obtain a wire rod having a diameter of 5.5 mm or 10 mm. I made it. Each of the hot-rolled wires mainly had a pearlite structure.
【００５３】なお、熱間圧延前の加熱には電気炉を用
い、炉中雰囲気はＣＯ、Ｈ2、Ｎ2及びＣＯ2で構成し、
（ＣＯの分圧）2／（ＣＯ2 の分圧）を変えることで、
外周部のＣ含有量を調整した。An electric furnace was used for heating before hot rolling, and the atmosphere in the furnace was composed of CO, H 2 , N 2 and CO 2 .
By changing (CO partial pressure) 2 / (CO 2 partial pressure),
The C content in the outer peripheral portion was adjusted.
【００５４】熱間圧延線材から横断サンプルを採取し、
その外周部（表層部近傍）のＣ含有量を測定した。すな
わち、波長分散型の電子線マイクロアナライザーを用い
て、Ｃ量の線分析を行い、外周から半径の４／２５０、
３／２５０、２／２５０及び１／２５０の深さの位置で
のＣ含有量を測定チャートから読み取り、この４点の平
均値を求めることで、外周から半径の１／５０の深さの
位置までの領域におけるＣ含有量の平均値を得た。図１
に、外周部（表層部近傍）のＣ含有量の一例として、後
述の表２の試験番号８における測定結果を示す。なお、
この図でＡ＝０．６５％としたのが上記のＣ含有量の平
均値である。A transverse sample was taken from the hot-rolled wire rod,
The C content in the outer peripheral portion (near the surface layer portion) was measured. That is, using a wavelength dispersion type electron beam microanalyzer, a line analysis of the amount of C was performed, and 4/250 of the radius from the outer periphery was obtained.
The C content at the depths of 3/250, 2/250, and 1/250 is read from the measurement chart, and the average value of these four points is obtained, whereby the position at a depth of 1/50 of the radius from the outer circumference is obtained. The average value of the C content in the region up to was obtained. FIG.
Table 2 shows the measurement results of Test No. 8 in Table 2 described below as an example of the C content in the outer peripheral portion (near the surface layer portion). In addition,
In this figure, A = 0.65% is the average value of the above-mentioned C content.
【００５５】前記のようにして得た熱間圧延線材を通常
の方法で酸洗し、潤滑剤を塗布した後、各ダイスでの減
面率が平均で２０％となるパススケジュールで、断線す
るまで伸線加工を行った。この際、真歪で２．６０以上
の伸線加工を行っても断線しない場合に、伸線加工性が
良好であると評価した。The hot-rolled wire obtained as described above is pickled by a usual method, and after applying a lubricant, the wire is broken according to a pass schedule in which the area reduction rate in each die is 20% on average. Wire drawing was performed up to. At this time, when the wire was not broken even when the wire was drawn at a true strain of 2.60 or more, the wire drawing was evaluated to be good.
【００５６】表２及び表３に、加熱炉雰囲気条件、熱間
圧延した線材のサイズ及び前記の各調査結果をまとめて
示す。なお、表２及び表３において、加熱炉の雰囲気条
件は条件１から５の順に、（ＣＯの分圧）2／（ＣＯ2の
分圧）が１２０、６０、３０、１５、５であることを示
す。Tables 2 and 3 summarize the atmosphere conditions of the heating furnace, the size of the hot-rolled wire rod, and the results of the above-mentioned investigations. In Tables 2 and 3, the atmosphere conditions of the heating furnace are such that (partial pressure of CO) 2 / (partial pressure of CO 2 ) is 120, 60, 30, 15, and 5 in the order of conditions 1 to 5. Is shown.
【００５７】[0057]
【表２】 [Table 2]
【００５８】[0058]
【表３】 [Table 3]
【００５９】表２及び表３から明らかなように、比較例
の鋼Ｄ、Ｆ、Ｈ、Ｊ及びＫを用いた試験番号の場合、つ
まり、Ｃ含有量が１．１％を超える試験番号１６〜２
０、Ｓｉ含有量が１．５％を超える試験番号２６〜３
０、Ｍｎ含有量が１．０％を超える試験番号３６〜４
０、Ｃｒ含有量が１．０％を超える試験番号４６〜５
０、Ｎ含有量が０．００６％を超える試験番号５１〜５
５は、伸線加工性が低く、真歪量２．６０に達せずに断
線を生じた。上記のうち試験番号１６、２６、３６、４
６、４７及び５１は、外周から半径の１／５０の深さの
位置までの領域におけるＣ含有量の平均値が０．９×Ｃ
％を超えるため、伸線加工性は極めて劣る。又、試験番
号２０、３０、４０及び５５は、外周から半径の１／５
０の深さの位置までの領域におけるＣ含有量の平均値が
０．６％を下回るため、線材表層部に初析フェライトが
生成し、伸線加工性は極めて劣る。As is clear from Tables 2 and 3, in the case of the test numbers using the steels D, F, H, J and K of the comparative examples, that is, test number 16 in which the C content exceeds 1.1%. ~ 2
0, Test numbers 26 to 3 in which the Si content exceeds 1.5%
0, Test numbers 36 to 4 in which the Mn content exceeds 1.0%
0, Test No. 46 to 5 with Cr content exceeding 1.0%
Test Nos. 51 to 5 with 0, N content exceeding 0.006%
In No. 5, the wire drawing workability was low, and the true strain amount did not reach 2.60, and the wire was broken. Test numbers 16, 26, 36, 4
6, 47 and 51 have an average C content of 0.9 × C in a region from the outer periphery to a position at a depth of 1/50 of the radius.
%, The drawability is extremely poor. Test numbers 20, 30, 40, and 55 are 1/5 of the radius from the outer circumference.
Since the average value of the C content in the region up to the position of the depth of 0 is less than 0.6%, proeutectoid ferrite is generated in the surface layer portion of the wire, and the drawability is extremely poor.
【００６０】化学組成が本発明で規定する含有量の範囲
内にある鋼であっても、試験番号６、７、１１、２１、
３１、４１、４２、５６、５７及び６１は、外周から半
径の１／５０の深さの位置までの領域におけるＣ含有量
の平均値が０．９×Ｃ％を超えるため、伸線加工性が低
く、真歪量２．６０に達せずに断線を生じた。[0060] Also the chemical composition is a steel within the range of the content defined in the present invention, the test number 6, 7,11,21,
31, 41, 42, 56, 57 and 61 have drawbacks in that the average value of the C content in the region from the outer periphery to the position at a depth of 1/50 of the radius exceeds 0.9 × C%. Was low, and the disconnection occurred without reaching the true strain of 2.60.
【００６１】又、化学組成が本発明で規定する含有量の
範囲内にある鋼であっても、試験番号１０、１４、１
５、２５、３４、３５、６０及び６５は、外周から半径
の１／５０の深さの位置までの領域におけるＣ含有量の
平均値が０．６％を下回るため、線材表層部に初析フェ
ライトが生成し、したがって、伸線加工性が低く、真歪
量２．６０に達せずに断線を生じた。[0061] Also, the chemical composition is a steel within the range of the content defined in the present invention, the test numbers 10, 14, 1
Nos. 5, 25, 34, 35, 60, and 65 have a primary deposition on the surface of the wire rod because the average value of the C content in the region from the outer periphery to a position at a depth of 1/50 of the radius is less than 0.6%. Ferrite was generated, and therefore, the wire drawing workability was low, and the wire was broken without reaching the true strain of 2.60.
【００６２】上記の比較例に対し、本発明で規定する条
件を満たす本発明例の場合には、伸線加工性が良好であ
り、真歪量で２．６０を超えて伸線加工しても断線を生
じなかった。In contrast to the above comparative example, in the case of the present invention which satisfies the conditions defined in the present invention, the wire drawing workability was good, and the true strain exceeded 2.60. No disconnection occurred.
【００６３】[0063]
【発明の効果】本発明の線材は伸線加工性に優れるの
で、この線材を素材としてワイヤロープ、ばね、ＰＣ鋼
線、ビードワイヤー、スチールコードなどを高い生産性
の下に歩留り良く提供することができる。この線材は通
常の設備によって比較的容易に製造でき、特別な設備を
必要としないので、その製造コストは低い。Since the wire of the present invention is excellent in wire drawing workability, it is possible to provide a wire rope, a spring, a PC steel wire, a bead wire, a steel cord and the like with a high yield with high productivity by using the wire as a material. Can be. This wire is relatively easy to manufacture with ordinary equipment and does not require special equipment, so its manufacturing cost is low.
【図１】波長分散型電子線マイクロアナライザーによる
線材横断面のＣ含有量の測定結果の一例を示す図であ
る。FIG. 1 is a view showing an example of a measurement result of a C content in a cross section of a wire rod by a wavelength dispersion type electron beam microanalyzer.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) C22C 38/00 301 C22C 38/54 ──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. 7 , DB name) C22C 38/00 301 C22C 38/54
Claims (2)
０．１〜１．５％、Ｍｎ：０．２〜１．０％、Ａｌ：
０．００１〜０．００３％、Ｃｒ：１．０％以下、Ｎ：
０．００６％以下、Ｃｕ：１．０％以下、Ｎｉ：２．０
％以下、Ｍｏ：０．５％以下、Ｃｏ：４．０％以下、
Ｖ：０．４％以下、Ｎｂ：０．１％以下、Ｔｉ：０．１
％以下、Ｂ：０．００５％以下、Ｐ：０．０５％以下、
Ｓ：０．０５％以下、希土類元素：０．１０％以下、Ｃ
ａ：０．０１％以下、Ｍｇ：０．０１％以下を含有し、
残部はＦｅ及び不可避不純物からなる鋼線材の横断面に
おいて、外周から前記鋼線材の半径の１／５０の深さの
位置までの領域におけるＣ含有量の平均値が０．６〜
０．９×Ｃ％（但し、Ｃは鋼線材のＣ含有量）であるこ
とを特徴とする伸線加工性に優れた鋼線材。C .: 0.7 to 1.1% by weight, Si:
0.1-1.5%, Mn: 0.2-1.0%, Al:
0.001 to 0.003%, Cr: 1.0% or less , N :
0.006% or less, Cu: 1.0% or less, Ni: 2.0
%, Mo: 0.5% or less, Co: 4.0% or less,
V: 0.4% or less, Nb: 0.1% or less, Ti: 0.1
%, B: 0.005% or less, P: 0.05% or less,
S: 0.05% or less, rare earth element: 0.10% or less, C
a: 0.01% or less, Mg: 0.01% or less,
In the cross section of the steel wire rod composed of Fe and unavoidable impurities, the average of the C content in the region from the outer periphery to a position at a depth of 1/50 of the radius of the steel wire rod is 0.6 to 0.6%.
A steel wire having excellent drawability, characterized by being 0.9 × C% (where C is the C content of the steel wire).
０．１〜１．５％、Ｍｎ：０．２〜１．０％、Ａｌ：
０．００１〜０．００３％、Ｃｒ：１．０％以下、Ｎ：
０．００６％以下、Ｃｕ：１．０％以下、Ｎｉ：２．０
％以下、Ｍｏ：０．５％以下、Ｗ：０．５％以下、Ｃ
ｏ：４．０％以下、Ｖ：０．４％以下、Ｎｂ：０．１％
以下、Ｔｉ：０．１％以下、Ｚｒ：０．１％以下、Ｂ：
０．００５％以下、Ｐ：０．０５％以下、Ｓ：０．０５
％以下、希土類元素：０．１０％以下、Ｃａ：０．０１
％以下、Ｍｇ：０．０１％以下を含有し、残部はＦｅ及
び不可避不純物からなる鋼線材の横断面において、外周
から前記鋼線材の半径の１／５０の深さの位置までの領
域におけるＣ含有量の平均値が０．６〜０．９×Ｃ％
（但し、Ｃは鋼線材のＣ含有量）であることを特徴とす
る伸線加工性に優れた鋼線材。2. C .: 0.7 to 1.1% by weight, Si:
0.1-1.5%, Mn: 0.2-1.0%, Al:
0.001 to 0.003%, Cr: 1.0% or less , N :
0.006% or less, Cu: 1.0% or less, Ni: 2.0
%, Mo: 0.5% or less, W: 0.5% or less, C
o: 4.0% or less, V: 0.4% or less, Nb: 0.1%
Hereinafter, Ti: 0.1% or less, Zr: 0.1% or less, B:
0.005% or less, P: 0.05% or less, S: 0.05
%, Rare earth element: 0.10% or less, Ca: 0.01
% And Mg: 0.01% or less, and the balance is C in a region from the outer periphery to a position at a depth of 1/50 of the radius of the steel wire in the cross section of the steel wire made of Fe and unavoidable impurities. The average value of the content is 0.6 to 0.9 × C%
(Where C is the C content of the steel wire), wherein the steel wire is excellent in wire drawing workability.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26982298A JP3536684B2 (en) | 1998-08-12 | 1998-09-24 | Steel wire with excellent wire drawing workability |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22787298 | 1998-08-12 | ||
| JP10-227872 | 1998-08-12 | ||
| JP26982298A JP3536684B2 (en) | 1998-08-12 | 1998-09-24 | Steel wire with excellent wire drawing workability |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2000119805A JP2000119805A (en) | 2000-04-25 |
| JP3536684B2 true JP3536684B2 (en) | 2004-06-14 |
Family
ID=26527923
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26982298A Expired - Fee Related JP3536684B2 (en) | 1998-08-12 | 1998-09-24 | Steel wire with excellent wire drawing workability |
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| Country | Link |
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Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2002050327A1 (en) * | 2000-12-20 | 2002-06-27 | Nippon Steel Corporation | High-strength spring steel and spring steel wire |
| JP5162875B2 (en) * | 2005-10-12 | 2013-03-13 | 新日鐵住金株式会社 | High strength wire rod excellent in wire drawing characteristics and method for producing the same |
| WO2008044356A1 (en) * | 2006-10-12 | 2008-04-17 | Nippon Steel Corporation | High-strength steel wire excelling in ductility and process for producing the same |
| SE531889C2 (en) | 2007-01-26 | 2009-09-01 | Sandvik Intellectual Property | Lead-free automatic steel and its use |
| JP6229793B2 (en) * | 2014-04-24 | 2017-11-15 | 新日鐵住金株式会社 | Filament for high strength steel cord |
| JP6229792B2 (en) * | 2014-04-24 | 2017-11-15 | 新日鐵住金株式会社 | High strength steel cord wire |
| CN106574343B (en) * | 2014-08-08 | 2019-06-25 | 日本制铁株式会社 | The carbon steel wire rod with high of excellent in wire-drawing workability |
| JP6416709B2 (en) * | 2015-07-21 | 2018-10-31 | 新日鐵住金株式会社 | High strength PC steel wire |
| CN105483556B (en) * | 2015-12-24 | 2017-10-10 | 江苏兴达钢帘线股份有限公司 | A kind of preparation method of high intensity steel bead wire material reinforcement method and steel bead wire |
| CN107723592B (en) * | 2017-09-30 | 2019-01-18 | 钢铁研究总院 | A kind of high-carbon wire rod steel and its production technology |
| CN114075639A (en) * | 2020-08-20 | 2022-02-22 | 宝山钢铁股份有限公司 | High-strength and high-fatigue-life steel for cable, wire rod and preparation method of steel |
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| Publication number | Publication date |
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| JP2000119805A (en) | 2000-04-25 |
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