JPH04280911A - Production of free cutting steel with ca - Google Patents
Production of free cutting steel with caInfo
- Publication number
- JPH04280911A JPH04280911A JP6368991A JP6368991A JPH04280911A JP H04280911 A JPH04280911 A JP H04280911A JP 6368991 A JP6368991 A JP 6368991A JP 6368991 A JP6368991 A JP 6368991A JP H04280911 A JPH04280911 A JP H04280911A
- Authority
- JP
- Japan
- Prior art keywords
- steel
- inclusions
- molten steel
- machinability
- composition
- 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.)
- Granted
Links
- 229910000915 Free machining steel Inorganic materials 0.000 title claims abstract description 12
- 238000004519 manufacturing process Methods 0.000 title claims description 9
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 38
- 239000010959 steel Substances 0.000 claims abstract description 38
- 239000002893 slag Substances 0.000 claims abstract description 14
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 21
- 229910052681 coesite Inorganic materials 0.000 claims description 12
- 229910052906 cristobalite Inorganic materials 0.000 claims description 12
- 239000000377 silicon dioxide Substances 0.000 claims description 12
- 229910052682 stishovite Inorganic materials 0.000 claims description 12
- 229910052905 tridymite Inorganic materials 0.000 claims description 12
- 235000012239 silicon dioxide Nutrition 0.000 claims description 9
- 229910000882 Ca alloy Inorganic materials 0.000 claims description 2
- 238000006243 chemical reaction Methods 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 5
- 230000002411 adverse Effects 0.000 abstract description 2
- 239000000203 mixture Substances 0.000 description 26
- 229910052661 anorthite Inorganic materials 0.000 description 8
- GWWPLLOVYSCJIO-UHFFFAOYSA-N dialuminum;calcium;disilicate Chemical compound [Al+3].[Al+3].[Ca+2].[O-][Si]([O-])([O-])[O-].[O-][Si]([O-])([O-])[O-] GWWPLLOVYSCJIO-UHFFFAOYSA-N 0.000 description 8
- 229910001678 gehlenite Inorganic materials 0.000 description 8
- 229910000532 Deoxidized steel Inorganic materials 0.000 description 7
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 6
- 229910052593 corundum Inorganic materials 0.000 description 6
- 229910001845 yogo sapphire Inorganic materials 0.000 description 6
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- BYFGZMCJNACEKR-UHFFFAOYSA-N aluminium(i) oxide Chemical compound [Al]O[Al] BYFGZMCJNACEKR-UHFFFAOYSA-N 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 238000010587 phase diagram Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000009749 continuous casting Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 229910007933 Si-M Inorganic materials 0.000 description 1
- 229910008318 Si—M Inorganic materials 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 238000004453 electron probe microanalysis Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
Landscapes
- Treatment Of Steel In Its Molten State (AREA)
Abstract
Description
【０００１】0001
【産業上の利用分野】本発明は鋼の被削性を改善するこ
とを目的として溶鋼にＣａを添加するＣａ快削鋼の溶製
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 Ca free-cutting steel by adding Ca to molten steel for the purpose of improving the machinability of the steel.
【０００２】0002
【従来の技術】従来、鋼材の被削性に及ぼす介在物組成
の影響については、例えば「第９６・９７回西山記念講
座、昭和５９年２月１５・１６日、日本鉄鋼協会」Ｐ４
２、表６によれば、被削性に及ぼす介在物の影響を被削
性に好ましい介在物と好ましくない介在物に分けて整理
して述べられている。この中で、Ｃａ成分を含む好まし
い介在物としてＣａＯ・Ａｌ２Ｏ３・２ＳｉＯ２（アノ
ーサイト）、２ＣａＯ・Ａｌ２Ｏ３・ＳｉＯ２（ゲーレ
ナイト）を挙げている。また、同上文献のＰ１７７には
、Ｃａ脱酸鋼で生成される介在物をＣａＯ−Ａｌ２Ｏ３
−ＳｉＯ２三元系であるとし、良好な工具寿命が得られ
る付着物組成を三元状態図の中で示し、最も多く報告さ
れているものはＡおよびＢのアノーサイトとゲーレナイ
トであると記述されている。一方、「電気製鋼」４４（
１９７３）１，Ｐ８１によれば、Ｃａ快削鋼中の含Ｃａ
脱酸生成物はアノーサイト、ゲーレナイトの領域を中心
としたものが多いと報告され、さらにその結果鍛延方向
に長伸したいわゆるＡ２系介在物となっており、工具寿
命曲線からこの延伸したＡ２系介在物組成が球状のＣ系
介在物より工具寿命の長寿命化をもたらすと報告されて
いる。
また、Ｃａ脱酸鋼の介在物組成の制御に関する公知文献
、あるいは特開昭６２−１９９７４９号公報のようなＣ
ａ−Ｓ系快削鋼の連続鋳造に関するものは見られるが、
Ｃａ脱酸鋼の被削性向上のため目標とする介在物組成を
実現するための製造技術に関する一貫した公知技術は存
在していない。[Prior Art] Conventionally, regarding the influence of inclusion composition on the machinability of steel materials, for example, "96th and 97th Nishiyama Memorial Lecture, February 15th and 16th, 1980, Japan Iron and Steel Institute," P4
2. According to Table 6, the influence of inclusions on machinability is categorized into inclusions that are favorable for machinability and inclusions that are unfavorable for machinability. Among these, CaO.Al2O3.2SiO2 (anorthite) and 2CaO.Al2O3.SiO2 (gehlenite) are listed as preferred inclusions containing Ca components. In addition, in P177 of the same document, inclusions generated in Ca deoxidized steel are described as CaO-Al2O3.
-SiO2 is assumed to be a ternary system, and the deposit composition that provides good tool life is shown in the ternary phase diagram, and the most commonly reported ones are A and B anorthite and gehlenite. ing. On the other hand, "Electric Steelmaking" 44 (
1973) 1, P81, Ca content in Ca free-cutting steel
It has been reported that many of the deoxidized products are mainly in the anorthite and gehlenite regions, and as a result, they are so-called A2-based inclusions that are elongated in the forging direction, and the tool life curve shows that the elongated A2 It has been reported that the C-based inclusion composition provides a longer tool life than the spherical C-based inclusions. In addition, known literature on controlling the inclusion composition of Ca-deoxidized steel or carbon
Although there are articles related to continuous casting of a-S free-cutting steel,
There is no consistent known technology regarding manufacturing technology for achieving a target inclusion composition for improving the machinability of Ca-deoxidized steel.
【０００３】0003
【発明が解決しようとする課題】本発明は、 鋼の被削
性を向上させるために必要とされる鋼中の非金属介在物
を、Ｃａ脱酸鋼としての製造過程において、目標とする
介在物組成を実現する鋼の溶製技術であり、鋼材中の好
ましい介在物組成とされているアノーサイトやゲーレナ
イトをより安定して具現せしめるものである。[Problems to be Solved by the Invention] The present invention aims to eliminate non-metallic inclusions in steel, which are necessary to improve the machinability of steel, by removing targeted inclusions in the manufacturing process of Ca-deoxidized steel. It is a steel melting technology that realizes a steel composition that has a more stable composition of anorthite and gehlenite, which are considered to be the preferred inclusion compositions in steel materials.
【０００４】0004
【課題を解決するための手段】本発明は被削性を要求さ
れるＣａ脱酸鋼の製造、すなわち、鋼の被削性向上を目
的として溶鋼にＣａを添加するＣａ快削鋼の溶製方法に
おいて、鋼浴中の全Ａｌ含有量を０．００２％以下とし
、次いでＣａを添加する際にこの溶鋼を保持する溶鋼容
器内のスラグ塩基度ＶおよびＣａの添加量Ｗにより下記
（１）式で定められる操業インデックスＩを下記（２）
式の範囲に制御してＣａを添加することを特徴とするＣ
ａ快削鋼の溶製方法である。
Ｉ＝１／Ｗ・Ｖ ・・・・・（１）４≦Ｉ≦１６
・・・・・（２）但し、Ｗ：溶鋼中に添加する
ＣａまたはＣａ合金のＣａ換算原単位（ｋｇ／Ｔｏｎ）
Ｖ：スラグの塩基度 （％ＣａＯ）／（％ＳｉＯ２）
図１は、Ｃａを添加する場合の操業インデックスＩとそ
の結果得られた鋼材（ビレット）中の介在物のアスペク
ト比の関係を表す図表であり、図２は、Ｃａ脱酸鋼の鋼
中の全Ａｌ量（以下Ｔ．Ａｌという）と介在物中のＡｌ
２Ｏ３の関係を表した図表で、いずれも、本発明者等に
よる実験の結果得られたものである。この発明において
、Ｃａ快削鋼は基本成分の含有量、および合金元素の含
有量は特別に限定する必要はないが、被削性の良好な介
在物を作り込むため、まず、Ｔ．Ａｌを以下の通り限定
する。目標介在物中のＡｌ２Ｏ３濃度は１５〜３０％で
あり、このＡｌ２Ｏ３濃度に対応するＴ．Ａｌは図２か
ら０．００２％が上限であるからこれを上限とする。[Means for Solving the Problems] The present invention is directed to the production of Ca-deoxidized steel that requires good machinability, that is, the production of Ca free-cutting steel in which Ca is added to molten steel for the purpose of improving the machinability of steel. In the method, the total Al content in the steel bath is 0.002% or less, and then when Ca is added, the slag basicity V in the molten steel container that holds this molten steel and the amount of Ca added W are determined by the following (1). The operation index I determined by the formula is shown below (2)
C, characterized in that Ca is added in a controlled manner within the range of the formula.
a) A method for producing free-cutting steel. I=1/W・V...(1) 4≦I≦16
...(2) However, W: Ca conversion basic unit of Ca or Ca alloy added to molten steel (kg/Ton) V: Basicity of slag (%CaO)/(%SiO2)
Figure 1 is a chart showing the relationship between the operation index I when Ca is added and the aspect ratio of inclusions in the resulting steel material (billet), and Figure 2 is a chart showing the relationship between the operation index I when Ca is added and the aspect ratio of inclusions in the resulting steel material (billet). Total Al content (hereinafter referred to as T.Al) and Al in inclusions
These are graphs showing the relationship between 2O3 and all of them were obtained as a result of experiments by the present inventors. In this invention, the content of basic components and the content of alloying elements in Ca free-cutting steel do not need to be particularly limited, but in order to incorporate inclusions with good machinability, T. Al is limited as follows. The Al2O3 concentration in the target inclusion is 15-30%, and the T. As shown in FIG. 2, the upper limit of Al is 0.002%, so this is set as the upper limit.
【０００５】また、操業インデックスＩにおいて、 適
正な取鍋スラグの塩基度Ｖの範囲は０．７〜１．５であ
る。Ｖ＜０．７の場合には取鍋耐火物の損傷が大きく工
業的には得策ではない。またＶ＞１．５の場合は、Ｃａ
Ｏが過大となり、好ましい介在物を鋼中に存在せしめる
ことができない。操業インデックスＩ≧４ではゲーレナ
イトに、Ｉ≧８ではアノーサイトに制御できる。Ｃａ添
加量Ｗについてはこれがゼロに近い場合は操業インデッ
クスは大となるが、介在物の大部分はＳｉＯ２系となり
、好ましい介在物とはならないので注意を要する。Ｃａ
添加量Ｗは、Ｗ≧０．０８ｋｇ／Ｔｏｎの範囲で適用で
きる。以上から操業インデックスＩの上限はＩ＝１６程
度まで実用可能である。[0005] Also, in terms of operation index I, the range of basicity V of suitable ladle slag is 0.7 to 1.5. If V<0.7, the damage to the ladle refractories will be large and this is not a good idea from an industrial perspective. Also, if V>1.5, Ca
O becomes excessive, and desirable inclusions cannot be made to exist in the steel. When the operation index I≧4, it can be controlled to Gehlenite, and when I≧8, it can be controlled to anorthite. Regarding the amount W of Ca added, if it is close to zero, the operation index will be large, but most of the inclusions will be SiO2-based, which is not a desirable inclusion, so care must be taken. Ca
The addition amount W can be applied within the range of W≧0.08 kg/Ton. From the above, it is practical that the upper limit of the operation index I is about I=16.
【０００６】[0006]
【作用】Ｃａ快削鋼のＣａ添加前のベース鋼はＳｉ−Ｍ
ｎ脱酸鋼であり、その介在物組成はＳｉＯ２−ＭｎＯ系
となっている。これらの介在物を低融点組成のアノーサ
イト；ＣａＯ・Ａｌ２Ｏ３・２ＳｉＯ２、あるいはゲー
レナイト；２ＣａＯ・Ａｌ２Ｏ３・ＳｉＯ２領域とする
ため、Ｃａ添加前の取鍋スラグのＣａＯ／ＳｉＯ２は約
１．０前後を目標とする。このことは、■最終的な介在
物組成はスラグ−メタル間の熱力学的平衡の影響を受け
ること。また、スラグの溶鋼への懸濁を想定、取鍋スラ
グ組成は目標介在物組成に近似させることを意味する。
■ＣａＯ／ＳｉＯ２を低めにすることは、熱力学的平衡
に従い、鋼中Ａｌを低位に保ち、鋼中へのＡｌインプッ
トの増加に伴う被削性に有害な硬質・非延性のＡｌ２Ｏ
３介在物の生成抑制効果をもたらすこと。■また、同時
に平衡酸素量が上昇し、以降のＣａ添加におけるＣａＯ
・Ａｌ２Ｏ３・ＳｉＯ２系低融点介在物への形態制御を
容易にする作用をもたらす。一方、Ｃａ添加により低融
点アノーサイトあるいはゲーレナイト領域の介在物組成
を得るためには、既述の条件に加えてＣａ添加量が重要
な要因であり、介在物の形態制御はＣａ添加量とＣａを
添加する際のその他の条件との組合せにより目標とする
組成領域への制御が可能となる。[Action] The base steel of Ca free-cutting steel before Ca addition is Si-M.
It is n-deoxidized steel, and its inclusion composition is SiO2-MnO system. In order to make these inclusions into the low melting point composition of anorthite (CaO・Al2O3・2SiO2) or gehlenite (2CaO・Al2O3・SiO2), we aim for CaO/SiO2 in the ladle slag before Ca addition to be around 1.0. shall be. This means that: (1) the final inclusion composition is influenced by the thermodynamic equilibrium between slag and metal; Furthermore, assuming that slag is suspended in molten steel, this means that the ladle slag composition should approximate the target inclusion composition. ■Reducing CaO/SiO2 is to keep Al in the steel at a low level according to thermodynamic equilibrium, and as the Al input into the steel increases, hard and non-ductile Al2O, which is harmful to machinability,
3. To bring about the effect of inhibiting the formation of inclusions. ■Also, at the same time, the equilibrium oxygen amount increases, and CaO in subsequent Ca addition increases.
- Provides an effect of facilitating the control of the morphology of Al2O3/SiO2-based low melting point inclusions. On the other hand, in order to obtain an inclusion composition in the low melting point anorthite or gehlenite region by adding Ca, the amount of Ca added is an important factor in addition to the conditions mentioned above, and the shape control of the inclusions depends on the amount of Ca added and the amount of Ca added. By combining with other conditions when adding , it is possible to control the composition to a target composition range.
【０００７】[0007]
【実施例】２７０Ｔ／ＣＨ転炉の出鋼時に溶鋼成分およ
び取鍋スラグ組成を調整した。Ｃａ添加前の溶鋼中のＴ
．Ａｌは０．００１％であり、取鍋内スラグの塩基度は
約１．０であった。その後Ｃａ添加はＣａ３１％−Ｓｉ
５６％組成のものをインジェクション法にて行った。
溶鋼は断面サイズ３５０×５６０ｍｍの曲げ型連続鋳造
機にて鋳造され、復熱炉経由で最終的には１６２×１６
２ｍｍのビレットにブレークダウンした。介在物形態の
調査は上記ビレットの対角線１／４長さ部からの切り出
しサンプルにより４００倍の顕微鏡にて行い、成分はＥ
ＰＭＡにて分析を行った。介在物形態の評価は顕微鏡観
察での介在物の長さｌと厚さｄの比；ｌ／ｄ（以下アス
ペクト比と定義）にて行った。表１に今回実炉試験を実
施した１０ヒートの溶鋼成分、スラグ成分、介在物組成
、およびアスペクト比を示す。ビレット介在物のアスペ
クト比は溶鋼へのＣａ添加原単位Ｗ〔ｋｇ／Ｔ−Ｓ〕と
取鍋スラグ塩基度Ｖ、すなわちＶ＝（％ＣａＯ）／（％
ＳｉＯ２）との組合せによる操業インデックスＩ、すな
わちＩ＝１／（Ｗ・Ｖ）と非常に大きな相関が認められ
る（図１）。すなわち、ビレット介在物のアスペクト比
は操業インデックスＩを制御することによりコントロー
ルが可能である。具体的には被削性の優れた延性介在物
を得るためには操業インデックスを大きくすると良い。
表２に図１の試験ヒートから３水準のアスペクト比の介
在物組成をＥＰＭＡで分析した結果を示す。さらに表２
の介在物組成をＣａＯ−Ａｌ２Ｏ３−ＳｉＯ２三元系状
態図上にプロットして図３に示す。これらの結果より、
アスペクト比の大きいＡおよびＢのヒートは被削性の優
れたアノーサイト、ゲーレナイト領域の介在物組成とな
っている。[Example] Molten steel composition and ladle slag composition were adjusted during tapping from a 270T/CH converter. T in molten steel before Ca addition
．． Al was 0.001%, and the basicity of the slag in the ladle was about 1.0. After that, Ca addition was performed using Ca31%-Si.
A sample with a composition of 56% was used by the injection method. Molten steel is cast using a bending type continuous casting machine with a cross-sectional size of 350 x 560 mm, and is finally cast into 162 x 16 mm via a recuperator.
It was broken down into a 2mm billet. The morphology of inclusions was investigated using a microscope with a magnification of 400 times using a sample cut from the diagonal 1/4 length of the billet.
Analysis was performed using PMA. The morphology of inclusions was evaluated based on the ratio of length l to thickness d of inclusions; l/d (hereinafter defined as aspect ratio) when observed under a microscope. Table 1 shows the molten steel composition, slag composition, inclusion composition, and aspect ratio of the 10 heats in which the actual furnace test was conducted. The aspect ratio of billet inclusions is determined by the basic unit of Ca addition to molten steel W [kg/T-S] and the ladle slag basicity V, that is, V = (%CaO) / (%
A very large correlation is observed with the operation index I in combination with SiO2), that is, I=1/(W·V) (FIG. 1). That is, the aspect ratio of billet inclusions can be controlled by controlling the operation index I. Specifically, in order to obtain ductile inclusions with excellent machinability, it is preferable to increase the operating index. Table 2 shows the results of EPMA analysis of inclusion compositions at three levels of aspect ratio from the test heat shown in FIG. Furthermore, Table 2
The inclusion composition of is plotted on a CaO-Al2O3-SiO2 ternary system phase diagram and is shown in FIG. From these results,
Heats A and B, which have a large aspect ratio, have inclusion compositions in the anorthite and gehlenite region, which have excellent machinability.
【０００８】[0008]
【表１Ｂ】[Table 1B]
【０００９】[0009]
【表１Ｂ】[Table 1B]
【００１０】0010
【表２】[Table 2]
【００１１】[0011]
【発明の効果】本発明によれば、被削性の優れた低融点
で延性に優れた介在物組成を得ることができ、被削性に
悪影響を及ぼす硬質・非延性の介在物の生成を防止する
ことができるので、被削性の優れたＣａ快削鋼を安定し
て製造することができる。[Effects of the Invention] According to the present invention, it is possible to obtain an inclusion composition with a low melting point and excellent ductility, which has excellent machinability, and prevents the formation of hard, non-ductile inclusions that have an adverse effect on machinability. Since this can be prevented, Ca free-cutting steel with excellent machinability can be stably produced.
【００１２】0012
【図１】Ｃａ添加の操業インデックスとビレット介在物
のアスペクト比を示す図表、FIG. 1 is a diagram showing the operational index of Ca addition and the aspect ratio of billet inclusions;
【図２】Ｃａ脱酸鋼の鋼中Ｔ．Ａｌと介在物中Ａｌ２０
３濃度の関係を示す図表、[Fig. 2] T. in Ca deoxidized steel. Al20 in Al and inclusions
A diagram showing the relationship between the three concentrations,
【図３】アスペクト比の３水準の介在物をＣａＯ−Ａｌ
２Ｏ３−ＳｉＯ２三元系状態図に示した図表である。[Figure 3] CaO-Al inclusions with three levels of aspect ratio
It is a chart shown in a 2O3-SiO2 ternary system phase diagram.
Claims (1)
製方法において、鋼浴中の全Ａｌ含有量を０．００２％
以下とし、次いでＣａを添加する際にこの溶鋼を保持す
る溶鋼容器内のスラグ塩基度ＶおよびＣａの添加量Ｗに
より下記（１）式で定められる操業インデックスＩを下
記（２）式の範囲に制御してＣａを添加することを特徴
とするＣａ快削鋼の溶製方法。 Ｉ＝１／Ｗ・Ｖ ・・・・・（１）４≦Ｉ≦１６
・・・・・（２）但し、Ｗ：溶鋼中に添加する
ＣａまたはＣａ合金のＣａ換算原単位（ｋｇ／Ｔｏｎ） Ｖ：スラグの塩基度 （％ＣａＯ）／（％ＳｉＯ２
）Claim 1: In a method for producing Ca free-cutting steel in which Ca is added to molten steel, the total Al content in the steel bath is reduced to 0.002%.
Then, when Ca is added, the operation index I determined by the following formula (1) based on the slag basicity V in the molten steel container that holds this molten steel and the addition amount W of Ca is set to the range of the following formula (2). A method for producing Ca free-cutting steel, characterized by adding Ca in a controlled manner. I=1/W・V...(1) 4≦I≦16
...(2) However, W: Ca conversion basic unit (kg/Ton) of Ca or Ca alloy added to molten steel V: Basicity of slag (%CaO)/(%SiO2
)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6368991A JPH0784612B2 (en) | 1991-03-06 | 1991-03-06 | Melting method of Ca free-cutting steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6368991A JPH0784612B2 (en) | 1991-03-06 | 1991-03-06 | Melting method of Ca free-cutting steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04280911A true JPH04280911A (en) | 1992-10-06 |
| JPH0784612B2 JPH0784612B2 (en) | 1995-09-13 |
Family
ID=13236599
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6368991A Expired - Lifetime JPH0784612B2 (en) | 1991-03-06 | 1991-03-06 | Melting method of Ca free-cutting steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0784612B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003293027A (en) * | 2002-04-09 | 2003-10-15 | Daido Steel Co Ltd | Method of producing calcium free-cutting stainless steel |
| JP2010144225A (en) * | 2008-12-19 | 2010-07-01 | Sumitomo Metal Ind Ltd | Steel for machine structure and manufacturing method of the same |
-
1991
- 1991-03-06 JP JP6368991A patent/JPH0784612B2/en not_active Expired - Lifetime
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003293027A (en) * | 2002-04-09 | 2003-10-15 | Daido Steel Co Ltd | Method of producing calcium free-cutting stainless steel |
| JP2010144225A (en) * | 2008-12-19 | 2010-07-01 | Sumitomo Metal Ind Ltd | Steel for machine structure and manufacturing method of the same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0784612B2 (en) | 1995-09-13 |
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