JP3083937B2 - Method for preventing coarsening of alumina in high carbon chromium bearing steel - Google Patents
Method for preventing coarsening of alumina in high carbon chromium bearing steelInfo
- Publication number
- JP3083937B2 JP3083937B2 JP05196269A JP19626993A JP3083937B2 JP 3083937 B2 JP3083937 B2 JP 3083937B2 JP 05196269 A JP05196269 A JP 05196269A JP 19626993 A JP19626993 A JP 19626993A JP 3083937 B2 JP3083937 B2 JP 3083937B2
- Authority
- JP
- Japan
- Prior art keywords
- alumina
- molten steel
- high carbon
- carbon chromium
- chromium bearing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Continuous Casting (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は高炭素クロム軸受鋼溶鋼
中のアルミナの粗大化を防止し、良質な高炭素クロム軸
受鋼鋼材を製造する方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing high quality high carbon chromium bearing steel by preventing coarsening of alumina in molten steel of high carbon chromium bearing steel.
【０００２】[0002]
【従来の技術】最近、鋼材に要求される品質は次第に厳
しく、かつ多様化してきており、より良質な鋼を製造す
るための技術の開発が望まれている。高炭素クロム軸受
鋼においても例外ではなく、基本品質特性である転動疲
労寿命を向上させるべく、疲労破壊の原因となる鋼材中
の酸化物（主としてアルミナ）を低減するための努力が
なされてきた。即ち、鋼材中の酸化物総量の目安である
Ｔ．Ｏ含有量を低減させるため、種々の技術が開発ある
いは検討されてきた。それらは、溶鋼の二次精錬段階で
のアルミナ除去、外来系酸化物の混入防止等である。2. Description of the Related Art In recent years, the quality required of steel materials has been increasingly severe and diversified, and there has been a demand for the development of techniques for producing higher quality steel. High carbon chromium bearing steels are no exception, and efforts have been made to reduce oxides (mainly alumina) in steel materials that cause fatigue failure in order to improve rolling fatigue life, which is a basic quality characteristic. . That is, T.P., which is a measure of the total amount of oxides in steel, is used. Various techniques have been developed or studied to reduce the O content. These are for removing alumina in the secondary refining stage of molten steel, preventing foreign oxides from being mixed, and the like.
【０００３】しかしながら、Ｔ．Ｏ含有量低減は技術的
限界に達してきたのも事実である。即ち、高炭素クロム
軸受鋼においては、Ｔ．Ｏ含有量を５ppm 以下にするこ
とが困難であり、一方Ｔ．Ｏ含有量が５ppm 程度でも酸
化物起因の疲労破壊が発生することがある。その原因は
アルミナが凝集・合体、即ちクラスター化により粗大化
し、疲労破壊の起点になるためである。それゆえ、この
問題は技術的に大きな障壁にぶつかっていた。[0003] However, T.A. It is true that the reduction of the O content has reached the technical limit. That is, in high carbon chromium bearing steel, T.V. It is difficult to reduce the O content to 5 ppm or less. Even when the O content is about 5 ppm, fatigue fracture due to oxides may occur. The reason is that alumina becomes coarse due to aggregation and coalescence, that is, clustering, and becomes a starting point of fatigue fracture. Therefore, the problem was technically a major barrier.
【０００４】このような状況に対して本発明者らは、新
しい概念による抜本的対策を確立した。それらは、特願
平３−３３７９２２号、特願平４−１４４９８号、特願
平５−５９３３３号であり、Ｍｇ添加により溶鋼中のア
ルミナ（Ａｌ2 Ｏ3 ）をＭｇＯ・Ａｌ2 Ｏ3 あるいはＭ
ｇＯに組成変換し、酸化物のサイズを微細化することを
基本とする。即ち、特願平３−３３７９２２号では、Ｍ
ｇ源としてＦｅ−Ｓｉ−Ｍｇ，Ｆｅ−Ｍｎ−Ｍｇ，Ｆｅ
−Ｓｉ−Ｍｎ−Ｍｇ，Ｓｉ−Ｍｇ合金を用いる方法、特
願平４−１４４９８号ではＭｇ源としてＭｇ−Ａｌ合金
を用いる方法を提案した。さらに、特願平５−５９３３
３号では、効率的組成変換方法として、ＭＧ合金添加前
の溶鋼中Ｓ含有量を０．００５重量％以下とする方法を
提案した。これらにより得られた高炭素クロム軸受鋼の
転動疲労寿命は飛躍的に向上した。[0004] The present inventors have established a drastic measure against such a situation by a new concept. These are Japanese Patent Application No. 3-337922, Japanese Patent Application No. 4-14498, and Japanese Patent Application No. 5-59333. The alumina (Al 2 O 3 ) in the molten steel is changed to MgO.Al 2 O 3 or M
Basically, the composition is converted to gO and the size of the oxide is reduced. That is, in Japanese Patent Application No. 3-337922, M
Fe-Si-Mg, Fe-Mn-Mg, Fe
-Si-Mn-Mg, a method using a Si-Mg alloy, and Japanese Patent Application No. 4-14498 proposed a method using an Mg-Al alloy as a Mg source. Furthermore, Japanese Patent Application No. 5-5933
No. 3 proposed a method for reducing the S content in molten steel before the addition of the MG alloy to 0.005% by weight or less as an efficient composition conversion method. The rolling fatigue life of the high carbon chromium bearing steel obtained by these methods was remarkably improved.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、上記Ｍ
ｇ合金を添加する方法は、添加のための特別な装置が必
要であること、合金貯蔵設備が必要なこと等の製造上の
問題点を抱えていた。本発明はこの問題点を有利に解決
したものであり、Ｍｇ合金を添加せずに、同法と同じ冶
金効果を創出するものである。Ｍｇ合金添加が不必要な
ため特別な装置等も不必要となる。However, the above M
The method of adding the g alloy had manufacturing problems such as the necessity of a special device for addition and the necessity of an alloy storage facility. The present invention advantageously solves this problem, and creates the same metallurgical effect as the method without adding an Mg alloy. Since the addition of the Mg alloy is unnecessary, a special device or the like is also unnecessary.
【０００６】[0006]
【課題を解決するための手段】本発明の要旨とするとこ
ろは以下の通りである。重量％で、Ｃ：０．９５〜１．
１０％、Ｓｉ：０．１５〜０．７０％、Ｍｎ：１．１５
％以下、Ｐ：０．０２５％以下、Ｓ：０．０２５％以
下、Ｃｒ：０．９０〜１．６０％、Ｍｏ：０．２５％以
下を含有する溶鋼から連続鋳造法により、鋳片を製造す
るに際し、連続鋳造用タンディッシュ内に存在するスラ
グの酸化度（＝ＦｅＯ＋Ｆｅ2 Ｏ3 ＋ＭｎＯ重量％）と
溶鋼中ｓｏｌ．Ａｌ含有量の関係を次式に従い制御する
ことを特徴とする高炭素クロム軸受鋼中アルミナの粗大
化防止方法を提案するものである。 式 Ｒ≦−１００（ｓｏｌ．Ａｌ％）＋５．０ 記号 Ｒ：スラグの酸化度（＝ＦｅＯ＋Ｆｅ2 Ｏ3 ＋Ｍ
ｎＯ）（重量％） ｓｏｌ．Ａｌ％：溶鋼中ｓｏｌ．Ａｌ含有量（重量％）The gist of the present invention is as follows. In weight%, C: 0.95-1.
10%, Si: 0.15 to 0.70%, Mn: 1.15
%, P: 0.025% or less, S: 0.025% or less, Cr: 0.90 to 1.60%, Mo: 0.25% or less. upon manufacturing, the degree of oxidation of the slag present in the continuous casting Tan in the dish (= FeO + Fe 2 O 3 + MnO % by weight) and in the molten steel sol. The present invention proposes a method for preventing coarsening of alumina in high carbon chromium bearing steel, characterized by controlling the relationship between Al contents according to the following equation. Formula R ≦ −100 (sol. Al%) + 5.0 Symbol R: Degree of oxidation of slag (= FeO + Fe 2 O 3 + M)
nO) (% by weight) sol. Al%: sol. Al content (% by weight)
【０００７】[0007]
【作用】まず、本発明の冶金原理について説明する。本
発明者らは、高炭素クロム軸受溶鋼のアルミナ粗大化機
構に関して種々の調査を行った結果、凝固直前即ち、連
続鋳造時のタンディッシュにおいて生成したアルミナが
凝固過程で凝集・合体する事実を解明した。このこと
は、連続鋳造用タンディッシュ以前に生成したアルミナ
は凝集・合体しても溶鋼中から浮上分離するが、連続鋳
造用タンディッシュで生成したアルミナは、工程が直ち
に凝固工程に移行するため浮上分離できないことを意味
する。この対策を検討した結果、連続鋳造用タンディッ
シュでのアルミナの生成を完全に防止すべきであるとの
結論に達した。First, the metallurgical principle of the present invention will be described. The present inventors have conducted various investigations on the mechanism of coarsening of alumina in high carbon chromium bearing molten steel, and clarified the fact that alumina generated in a tundish immediately before solidification, that is, in a tundish during continuous casting, aggregates and coalesces during solidification. did. This means that alumina produced before the tundish for continuous casting floats and separates from the molten steel even if it is agglomerated and coalesced. It means that they cannot be separated. As a result of studying this countermeasure, it was concluded that the formation of alumina in a tundish for continuous casting should be completely prevented.
【０００８】即ち、連続鋳造用タンディッシュでのアル
ミナ生成は、溶鋼中ｓｏｌ．Ａｌがスラグ中のＦｅＯ，
Ｆｅ2 Ｏ3 ，ＭｎＯにより酸化されることによりもたら
される。それゆえ、スラグ中のＦｅＯ＋Ｆｅ2 Ｏ3 ＋Ｍ
ｎＯ重量％を低下させ、アルミナ生成を防止すればよ
い。しかし、ＦｅＯ＋Ｆｅ2 Ｏ3 ＋ＭｎＯ重量％を低下
させることは後述のようにコスト増を招くことになるた
め、必要最小限の低下幅に留めることが有利である。本
発明はこのような観点から、本発明者らの実験により得
られたものであり、（１）式で表すことができる。 Ｒ≦−１００（ｓｏｌ．Ａｌ％）＋５．０ …………………（１） ここに、Ｒ：スラグの酸化度（＝ＦｅＯ＋Ｆｅ2 Ｏ3 ＋
ＭｎＯ（重量％））、ｓｏｌ．Ａｌ％：溶鋼中ｓｏｌ．
Ａｌ含有量（重量％）である。That is, alumina formation in a tundish for continuous casting is carried out by sol. Al is FeO in slag,
It is brought about by oxidation by Fe 2 O 3 and MnO. Therefore, FeO + Fe 2 O 3 + M in slag
What is necessary is just to reduce nO weight% and prevent alumina production. However, reducing FeO + Fe 2 O 3 + MnO weight% leads to an increase in cost as described later, so it is advantageous to keep the reduction to the minimum necessary. The present invention has been obtained from such viewpoints through experiments performed by the present inventors, and can be expressed by equation (1). R ≦ −100 (sol. Al%) + 5.0 (1) where, R: degree of oxidation of slag (= FeO + Fe 2 O 3 +
MnO (% by weight)), sol. Al%: sol.
The Al content (% by weight).
【０００９】上記（１）式を満足するようにスラグの酸
化度を低下させればよいが、（１）式の最大の特徴は溶
鋼中ｓｏｌ．Ａｌ含有量の低下に応じて、スラグの酸化
度を高めてもよい点にある。この点がスラグの酸化度調
整（低下）のために添加するフラックスの節減につなが
り、コスト的に極めて有利となる。即ち、ｓｏｌ．Ａｌ
が０．０２５％の場合にはスラグの酸化度を２．５％以
下にする必要があるが、０．０１５％の場合にはスラグ
の酸化度を３．５％以下にすればよいことになる。ｓｏ
ｌ．Ａｌが低い場合にはＡｌの活量が小さく、スラグの
酸化度を高めてもＡｌは酸化されにくいことを意味す
る。The degree of oxidation of the slag may be reduced so as to satisfy the above equation (1), but the biggest feature of the equation (1) is that sol. The point is that the degree of oxidation of the slag may be increased in accordance with the decrease in the Al content. This leads to a reduction in the amount of flux added for adjusting (decreasing) the degree of oxidation of the slag, which is extremely advantageous in terms of cost. That is, sol. Al
Is 0.025%, the degree of oxidation of the slag needs to be 2.5% or less, but if it is 0.015%, the degree of oxidation of the slag should be 3.5% or less. Become. so
l. When Al is low, the activity of Al is small, which means that Al is hardly oxidized even if the degree of oxidation of slag is increased.
【００１０】次に、実際の操業方法について述べる。操
業方法については特定するものではないが、一般にはタ
ンディッシュにおいて、ＣａＯ，Ａｌ2 Ｏ3 ，ＣａＦ2
等からなるフラックスを添加し、すでに生成しているタ
ンディッシュ内スラグ中のＦｅＯ＋Ｆｅ2 Ｏ3 ＋ＭｎＯ
を希釈する方法が現実的である。従って溶鋼中ｓｏｌ．
Ａｌ含有量の低下に応じて、スラグの酸化度を高めてよ
ければ、添加フラックス量の節減につながり、コスト的
低減が可能となる。この際、添加フラックス量は以下の
ように、溶鋼ｓｏｌ．Ａｌ分析値、またすでに生成して
いるタンディッシュ内スラグの量及びＦｅＯ＋Ｆｅ2 Ｏ
3 ＋ＭｎＯ含有量から求めることができる。Next, an actual operation method will be described. The operation method is not specified, but generally, in a tundish, CaO, Al 2 O 3 , CaF 2
And a flux consisting of FeO + Fe 2 O 3 + MnO in the slag in the tundish already generated.
The method of diluting is realistic. Therefore, sol.
If the degree of oxidation of the slag can be increased in accordance with the decrease in the Al content, the amount of added flux can be reduced, and the cost can be reduced. At this time, the amount of the added flux was as follows. Al analysis value, amount of slag in tundish already generated and FeO + Fe 2 O
It can be determined from the 3 + MnO content.
【００１１】溶鋼ｓｏｌ．Ａｌ含有量は当該チャージ
の連続鋳造の前工程、例えばＲＨ工程後溶鋼のｓｏｌ．
Ａｌ分析値を採用できる。この情報はＲＨ工程後溶鋼サ
ンプルの迅速分析によって有効なものとなる。 タンディッシュには当該チャージの前チャージのスラ
グが残留している。その量及び組成は前チャージの鋼種
規格によりほぼ一定であるから、タンディッシュ内スラ
グの量及びＦｅＯ＋Ｆｅ2 Ｏ3 ＋ＭｎＯ含有量を把握で
きる。なお、タンディッシュ内スラグのＦｅＯ，Ｆｅ2
Ｏ3 ，ＭｎＯ以外の組成については、特に限定するもの
ではない。[0011] Molten steel sol. The Al content is determined in the pre-process of continuous casting of the charge, for example, sol.
An Al analysis value can be adopted. This information can be validated by rapid analysis of the molten steel sample after the RH process. The slag of the charge before the charge remains in the tundish. Since the amount and composition of the slag in the tundish and the content of FeO + Fe 2 O 3 + MnO can be grasped because the amount and the composition are almost constant according to the steel type standard of the pre-charge. The slag in the tundish FeO, Fe 2
The composition other than O 3 and MnO is not particularly limited.
【００１２】本発明において、溶鋼組成を、重量％で、
Ｃ：０．９５〜１．１０％、Ｓｉ：０．１５〜０．７０
％、Ｍｎ：１．１５％以下、Ｐ：０．０２５％以下、
Ｓ：０．０２５％以下、Ｃｒ：０．９０〜１．６０％、
Ｍｏ：０．２５％以下を含有する高炭素クロム軸受鋼
（ＪＩＳ規格：ＳＵＪ）相当に規定する理由は、当該鋼
種について本発明の効果が出現しやすいからである。即
ち、高炭素クロム軸受鋼溶鋼では高炭素であり、Ｔ．Ｏ
含有量も１０ppm 以下であり、かつ酸化物がほとんどＡ
ｌ2 Ｏ3 であるため、本発明の適用が可能である。In the present invention, the molten steel composition is expressed in terms of% by weight,
C: 0.95 to 1.10%, Si: 0.15 to 0.70
%, Mn: 1.15% or less, P: 0.025% or less,
S: 0.025% or less, Cr: 0.90 to 1.60%,
The reason why the high carbon chromium bearing steel containing Mo: 0.25% or less (JIS standard: SUJ) is specified is that the effect of the present invention easily appears for the steel type. That is, high carbon chromium bearing steel molten steel has high carbon, O
The content is 10 ppm or less, and the oxide is almost A
Since it is l 2 O 3 , the present invention can be applied.
【００１３】[0013]
【実施例】本発明法に従い３００ton 転炉を用いて５チ
ャージ高炭素クロム軸受鋼を製造した。まず、３００to
n 転炉にて酸素吹錬を行って得た母溶鋼を取鍋へ出鋼し
た。この際、Ｓｉ，Ｍｎ，Ｃｒを添加した。続いて取鍋
内溶鋼にＣ電極を挿入し通電加熱し、溶鋼の温度低下を
防止しながら、Ａｌを添加すると共にＳｉ，Ｍｎ，Ｃ
ｒ，Ｍｏも添加しこれらの微調整も実施した。次に取鍋
内溶鋼にＲＨ処理を施し、処理後の溶鋼をサンプリング
し直ちに分析した。EXAMPLE A 5-charge high carbon chromium bearing steel was produced using a 300 ton converter in accordance with the method of the present invention. First, 300to
n The mother molten steel obtained by oxygen blowing in a converter was tapped into a ladle. At this time, Si, Mn, and Cr were added. Subsequently, a C electrode is inserted into the molten steel in the ladle and heated by heating to prevent the temperature of the molten steel from decreasing, while adding Al and simultaneously adding Si, Mn, and C.
These fine adjustments were also made by adding r and Mo. Next, the molten steel in the ladle was subjected to RH treatment, and the molten steel after the treatment was sampled and immediately analyzed.
【００１４】その結果、表１に示す組成の高炭素クロム
軸受鋼母溶鋼を得た。この溶鋼から連続鋳造、棒鋼圧延
により高炭素クロム軸受鋼６５φ素材を製造した。この
際、連続鋳造用タンディッシュ内の残留スラグ量、組成
及び添加フラックスは表２に示すように本発明法の適正
範囲とした。得られた素材の転動疲労試験を行ったとこ
ろ、疲労寿命は表３に示すように比較例に比べ極めて良
好であり、また素材中の酸化物を調査した結果、アルミ
ナクラスターは認められず、そのサイズは５．５μ以下
の微細アルミナが存在するのみであった。As a result, a high-carbon chromium bearing steel mother molten steel having the composition shown in Table 1 was obtained. A high carbon chromium bearing steel 65φ material was manufactured from the molten steel by continuous casting and bar rolling. At this time, the amount of residual slag, the composition, and the added flux in the tundish for continuous casting were within the appropriate ranges for the method of the present invention as shown in Table 2. When a rolling fatigue test was performed on the obtained material, the fatigue life was extremely good as compared with the comparative example as shown in Table 3, and as a result of examining oxides in the material, no alumina cluster was observed. Its size was only the presence of fine alumina of 5.5 μ or less.
【００１５】[0015]
【表１】 [Table 1]
【００１６】[0016]
【表２】 [Table 2]
【００１７】[0017]
【表３】 [Table 3]
【００１８】〔比較例１〕実施例の方法に準じて高炭素
クロム軸受鋼を５チャージ溶製し、６５φ素材を製造し
た。ＲＨ処理後溶鋼の組成を表１、連続鋳造用タンディ
ッシュ内の残留スラグ量、組成及び添加フラックスを表
２、転動疲労試験成績を表３に示す。本比較例では、実
施例と異なり、連続鋳造用タンディッシュ内の残留スラ
グ量、組成及び添加フラックスは本発明法の適正範囲外
とした。その他の条件は実施例と全く同様である。得ら
れた素材の転動疲労試験を行ったところ、疲労寿命は実
施例に比べ好ましくない成績となった。また、素材中の
酸化物を調査した結果、アルミナクラスター及びアルミ
ナが混在しており、そのクラスターのサイズは最大１０
〜２５μであり実施例に比べて極めて粗大であった。Comparative Example 1 A high-carbon chromium bearing steel was melted for 5 charges in accordance with the method of the embodiment to produce a 65φ material. Table 1 shows the composition of the molten steel after the RH treatment, Table 2 shows the residual slag amount, composition and added flux in the tundish for continuous casting, and Table 3 shows the rolling fatigue test results. In this comparative example, unlike the examples, the amount of residual slag, the composition, and the added flux in the tundish for continuous casting were outside the appropriate ranges of the method of the present invention. Other conditions are exactly the same as those of the embodiment. When a rolling fatigue test was performed on the obtained material, the fatigue life was unfavorable as compared with the examples. In addition, as a result of investigating oxides in the material, alumina clusters and alumina were mixed, and the size of the clusters was up to 10
-25 μm, which was extremely coarse as compared with the example.
【００１９】〔比較例２〕３００ton 転炉にて母溶鋼を
溶製し、取鍋へ出鋼する際にＳｉ，Ｍｎ，Ｃｒ，Ａｌを
添加した。続いて取鍋内溶鋼にＣ電極を挿入し通電加熱
し、溶鋼の温度低下を防止しながら、Ａｌを添加すると
共にＳｉ，Ｍｎ，Ｃｒ，Ｍｏも添加しこれらの微調整も
実施した。次に、取鍋内溶鋼にＲＨ処理を施した後、取
鍋内溶鋼にＭｇ１０％−Ｓｉ４５％−Ｆｅ４５％のＭｇ
合金の粉末を内径６mmφ、厚み０．３mmの鉄被覆ワイヤ
ーにて添加した。添加速度はＭｇ分で０．０５kg/ton溶
鋼／分であり、Ｍｇ添加量は溶鋼に対して０．０１８％
である。これにより表１に示す組成の高炭素クロム軸受
鋼母溶鋼を得た。[Comparative Example 2] Base molten steel was melted in a 300 ton converter, and Si, Mn, Cr and Al were added when tapping the steel into a ladle. Subsequently, a C electrode was inserted into the molten steel in the ladle and heated by heating, and while preventing the temperature of the molten steel from decreasing, Al, Si, Mn, Cr, and Mo were also added to finely adjust these. Next, after subjecting the molten steel in the ladle to RH treatment, the molten steel in the ladle was subjected to Mg10% -Si45% -Fe45% Mg.
The alloy powder was added with an iron-coated wire having an inner diameter of 6 mm and a thickness of 0.3 mm. The addition rate is 0.05 kg / ton molten steel / minute in terms of Mg, and the amount of added Mg is 0.018% based on the molten steel.
It is. As a result, a high carbon chromium bearing steel mother molten steel having the composition shown in Table 1 was obtained.
【００２０】このようにして得られた溶鋼から連続鋳
造、棒鋼圧延により高炭素クロム軸受鋼６５φ素材を製
造した。この際、連続鋳造用タンディッシュ内にはフラ
ックスは添加せず、スラグの組成制御は実施しなかっ
た。この素材の転動疲労試験を行ったところ、疲労寿命
は表３に示すように、実施例と同等の成績であった。ま
た、素材中の酸化物を調査した結果、酸化物はほとんど
Ａｌ2 Ｏ3 ・ＭｇＯ及びＭｇＯであり、そのサイズは
５．０μ以下と実施例と同等であった。以上より、本発
明法はＭｇ合金添加法と同等の効果を有することが確認
された。From the molten steel thus obtained, a high carbon chromium bearing steel 65φ material was produced by continuous casting and bar rolling. At this time, no flux was added into the tundish for continuous casting, and the composition of the slag was not controlled. When a rolling fatigue test was performed on this material, the fatigue life was equivalent to that of the example, as shown in Table 3. Further, as a result of examining the oxides in the raw material, the oxides were almost Al 2 O 3 .MgO and MgO, and the size was 5.0 μm or less, which was equivalent to that of the examples. From the above, it was confirmed that the method of the present invention had the same effect as the Mg alloy addition method.
【００２１】[0021]
【発明の効果】本発明により高炭素クロム軸受鋼鋼材の
アルミナのクラスター化による粗大化を防止でき、その
サイズを微細にすることが可能となった。これにより、
酸化物系介在物の悪影響を解消することができ、疲労特
性等材質特性に優れた高炭素クロム軸受鋼鋼材の供給が
可能となり、産業界にとって極めて有益である。According to the present invention, coarsening due to clustering of alumina in high carbon chromium bearing steel can be prevented, and its size can be reduced. This allows
The adverse effect of oxide-based inclusions can be eliminated, and a high-carbon chromium bearing steel having excellent material properties such as fatigue properties can be supplied, which is extremely useful for the industry.
───────────────────────────────────────────────────── フロントページの続き (51)Int.Cl.7 識別記号 ＦＩ Ｃ２２Ｃ 38/00 ３０１ Ｃ２２Ｃ 38/00 ３０１Ｚ 38/22 38/22 (56)参考文献 特開 平４−262834（ＪＰ，Ａ) 特開 平３−204143（ＪＰ，Ａ) 特開 平６−297089（ＪＰ，Ａ) 特開 平２−92444（ＪＰ，Ａ) 特開 平６−248324（ＪＰ，Ａ) 特開 平５−311225（ＪＰ，Ａ) 特開 平６−246393（ＪＰ，Ａ) 特開 昭49−111826（ＪＰ，Ａ) 特開 昭48−85429（ＪＰ，Ａ) 特開 昭62−63651（ＪＰ，Ａ) 特開 昭62−63650（ＪＰ，Ａ) 特開 昭61−272349（ＪＰ，Ａ) 特開 昭60−194047（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) B22D 11/11 B22D 1/00 B22D 11/00 C21C 7/076 C22C 38/06 C22C 38/00 301 C22C 38/22 ──────────────────────────────────────────────────続 き Continuation of front page (51) Int.Cl. 7 Identification symbol FI C22C 38/00 301 C22C 38/00 301Z 38/22 38/22 (56) References JP-A-4-262834 (JP, A) JP-A-3-204143 (JP, A) JP-A-6-297089 (JP, A) JP-A-2-92444 (JP, A) JP-A-6-248324 (JP, A) JP-A-5-311225 (JP, A) JP-A-6-246393 (JP, A) JP-A-49-111826 (JP, A) JP-A-48-85429 (JP, A) JP-A-62-63651 (JP, A) JP-A-62-63650 (JP, A) JP-A-61-272349 (JP, A) JP-A-60-194047 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) B22D 11 / 11 B22D 1/00 B22D 11/00 C21C 7/076 C22C 38/06 C22C 38/00 301 C22C 38/22
Claims (1)
際し、連続鋳造用タンディッシュ内に存在するスラグの
酸化度（＝ＦｅＯ＋Ｆｅ2 Ｏ3 ＋ＭｎＯ重量％）と溶鋼
中ｓｏｌ．Ａｌ含有量の関係を次式に従い制御すること
を特徴とする高炭素クロム軸受鋼中アルミナの粗大化防
止方法。 式 Ｒ≦−１００（ｓｏｌ．Ａｌ％）＋５．０ 記号 Ｒ：スラグの酸化度（＝ＦｅＯ＋Ｆｅ2 Ｏ3 ＋Ｍ
ｎＯ）（重量％） ｓｏｌ．Ａｌ％：溶鋼中ｓｏｌ．Ａｌ含有量（重量％）C: 0.95 to 1.10%, Si: 0.15 to 0.70%, Mn: 1.15% or less, P: 0.025% or less, S: 0% by weight 0.025% or less, Cr: 0.90 to 1.60%, Mo: 0.25% or less When producing a slab by continuous casting from molten steel, the slag present in the tundish for continuous casting is manufactured. oxidation degree (= FeO + Fe 2 O 3 + MnO % by weight) and in the molten steel sol. A method for preventing coarsening of alumina in high carbon chromium bearing steel, wherein the relationship between Al contents is controlled according to the following equation. Formula R ≦ −100 (sol. Al%) + 5.0 Symbol R: Degree of oxidation of slag (= FeO + Fe 2 O 3 + M)
nO) (% by weight) sol. Al%: sol. Al content (% by weight)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05196269A JP3083937B2 (en) | 1993-08-06 | 1993-08-06 | Method for preventing coarsening of alumina in high carbon chromium bearing steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP05196269A JP3083937B2 (en) | 1993-08-06 | 1993-08-06 | Method for preventing coarsening of alumina in high carbon chromium bearing steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0747451A JPH0747451A (en) | 1995-02-21 |
| JP3083937B2 true JP3083937B2 (en) | 2000-09-04 |
Family
ID=16355000
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP05196269A Expired - Fee Related JP3083937B2 (en) | 1993-08-06 | 1993-08-06 | Method for preventing coarsening of alumina in high carbon chromium bearing steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3083937B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5736990B2 (en) * | 2011-06-15 | 2015-06-17 | Ｊｆｅスチール株式会社 | Bearing material |
| CN103266275A (en) * | 2013-05-23 | 2013-08-28 | 江苏久联冶金机械制造有限公司 | Boron-containing high-silicon case steel material and isothermal quenching method |
-
1993
- 1993-08-06 JP JP05196269A patent/JP3083937B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0747451A (en) | 1995-02-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO1997036010A1 (en) | Process for producing aluminum-killed steel free of cluster | |
| JP3550924B2 (en) | Method for manufacturing high carbon steel wire and wire | |
| WO2004081250A2 (en) | Steel having finely dispersed inclusions | |
| EP0284694B1 (en) | Controlling dissolved oxygen content in molten steel | |
| JP3083937B2 (en) | Method for preventing coarsening of alumina in high carbon chromium bearing steel | |
| JPH06158226A (en) | Spring steel excellent in fatigue characteristic | |
| US6355089B2 (en) | Process for the manufacture of carbon or low-alloy steel with improved machinability | |
| JP3647969B2 (en) | Method for refinement of harmful inclusions in steel | |
| US5391241A (en) | Fe-Ni alloy cold-rolled sheet excellent in cleanliness and etching pierceability | |
| JP3036362B2 (en) | Manufacturing method of oxide dispersion steel | |
| JPH11323426A (en) | Production of high clean steel | |
| JP3825570B2 (en) | Austenitic stainless steel slab excellent in workability and method for producing the same | |
| JP3230070B2 (en) | How to add Mg to molten steel | |
| JP4034700B2 (en) | Manufacturing method of high S free cutting steel with excellent machinability and high S free cutting steel | |
| JPH08225820A (en) | Production of high carbon silicon killed steel | |
| JP2002105527A (en) | Method for producing high cleanliness steel | |
| JP2855334B2 (en) | Modification method of molten steel slag | |
| JP2684307B2 (en) | Highly efficient method for preventing Al2O3 aggregation in molten steel | |
| JP3230065B2 (en) | Manufacturing method of molten steel for continuous casting | |
| JPH06212237A (en) | Prduction of high carbon steel for high strength extra fine wire | |
| JP2001032014A (en) | Method for manufacturing steel plate for sheet steel | |
| JP3033001B2 (en) | Method for miniaturizing oxide inclusions | |
| JPH1068011A (en) | Production of oxide-dispersed steel | |
| JPS626605B2 (en) | ||
| JP3217952B2 (en) | Steel material for steel plate for can with few defects and manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20000523 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080630 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090630 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090630 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100630 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100630 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110630 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110630 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120630 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130630 Year of fee payment: 13 |
|
| LAPS | Cancellation because of no payment of annual fees |