JP2001321907A - Method for producing continuous casting slab and continuous casting slab - Google Patents
Method for producing continuous casting slab and continuous casting slabInfo
- Publication number
- JP2001321907A JP2001321907A JP2000142522A JP2000142522A JP2001321907A JP 2001321907 A JP2001321907 A JP 2001321907A JP 2000142522 A JP2000142522 A JP 2000142522A JP 2000142522 A JP2000142522 A JP 2000142522A JP 2001321907 A JP2001321907 A JP 2001321907A
- Authority
- JP
- Japan
- Prior art keywords
- slab
- alloy element
- mold
- continuous casting
- concentration
- 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.)
- Withdrawn
Links
Landscapes
- Continuous Casting (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、鋳片断面積が５０
０ｃｍ2 以下の鋳片を製造する方法において、溶鋼か
ら、直接、連続鋳造鋳型内にて、鋳片表層の合金元素濃
度が鋳片内層部と比較して高い複層状の連鋳鋳片を製造
する方法と、その連鋳鋳片に関する。TECHNICAL FIELD The present invention relates to a slab having a cross section of 50 slabs.
In a method for producing a cast slab of 0 cm 2 or less, a continuous cast slab is produced from molten steel directly in a continuous casting mold in which the alloy element concentration of the surface layer of the slab is higher than that of the slab inner layer. And a continuous cast slab.
【０００２】[0002]
【従来の技術】発明者らは、図１に示すように、特開平
８−２９０２３５号（特願平７−１１５２８３号）公報
にて、所定の合金元素を含有した連鋳パウダー１３を用
いると共に、連続鋳造鋳型内の上部に電磁攪拌装置３０
を設置し、鋳型内の溶鋼プール中の水平断面内で旋回流
３１を形成し、かつ、鋳型内に溶鋼を供給する浸漬ノズ
ル２の吐出孔を攪拌域９よりも下方に設けることによ
り、鋳型内において、上部に、攪拌流により前記合金元
素が均一に溶解・混合した領域を形成し、また、その下
方に、合金元素の濃度が低い領域を形成することで、合
金元素の表層濃度が内層に比べて高い複層状の鋳片を製
造することを特徴とする連鋳鋳片の製造方法を、また、
特開平８−２９０２３６号（特願平７−１１５２８４
号）公報にて、鋳型上部、下部に、それぞれ溶鋼プール
中で旋回攪拌流を形成し、その下方で、直流磁界を形成
することができる電磁力を適用しつつ、鋳型内にパウダ
ーと共に溶鋼中に添加する合金元素の粒あるいは粉を添
加することで、鋳片表層部のみに添加した合金元素を富
化する方法を開示した。2. Description of the Related Art As shown in FIG. 1, the inventors of the present invention disclosed in Japanese Patent Application Laid-Open No. Hei 8-290235 (Japanese Patent Application No. Hei 7-115283), using a continuously cast powder 13 containing a predetermined alloy element. , The electromagnetic stirring device 30
By forming a swirling flow 31 in a horizontal section in the molten steel pool in the mold and providing the discharge hole of the immersion nozzle 2 for supplying molten steel into the mold below the stirring zone 9, In the upper part, a region in which the alloy element is uniformly dissolved and mixed by the agitated flow is formed, and a region in which the concentration of the alloy element is low is formed therebelow, so that the surface concentration of the alloy element becomes lower in the inner layer. A method for producing a continuous cast slab, characterized by producing a multilayer cast slab higher than
JP-A-8-290236 (Japanese Patent Application No. Hei 7-115284)
No.) In the gazette, a swirling agitated flow is formed in the molten steel pool at the top and bottom of the mold, respectively. A method for enriching the alloy element added only to the surface layer portion of the slab by adding grains or powder of the alloy element to be added to the alloy is disclosed.
【０００３】[0003]
【発明が解決しようとする課題】ブルームやビレット鋳
造においては、一般的に、凝固組織を等軸晶化するため
鋳型内電磁攪拌が用いられている。加えて、その電磁攪
拌を設置する位置については、スラブ鋳造の場合と異な
り、湯面から数１００ｍｍ下側に設置されている場合が
多い。このような状況で、例えば、特開平８−２９０２
３５号公報記載の方法のように、電磁攪拌装置よりも下
方にノズル吐出孔を設置しようとすると、浸漬深さがあ
まりにも過大となることや、湯面への熱供給が十分に図
れず、デッケルやノズル周りでの地金張り等、操業上の
課題が生じ、また、それに伴い鋳片品質上の課題が生じ
る。In bloom or billet casting, electromagnetic stirring in a mold is generally used to make a solidified structure equiaxed. In addition, the position where the electromagnetic stirring is installed is different from the case of slab casting, and is often installed several hundred mm below the molten metal surface. In such a situation, for example, Japanese Patent Laid-Open No. 8-2902
When the nozzle discharge hole is installed below the electromagnetic stirrer as in the method described in Japanese Patent No. 35, the immersion depth becomes too large, and the heat supply to the molten metal surface cannot be sufficiently achieved. Operational problems such as deckle and metal plating around the nozzle occur, and accompanying this, problems in slab quality arise.
【０００４】そこで、本発明は、上記課題を解決し、鋳
片断面積が５００ｃｍ2 以下の鋳片を製造する場合にお
いても、連鋳パウダーから鋳型内溶鋼プール中に合金添
加を行い、かつ、鋳片表層部のみにおける合金元素濃度
が均一に富化された連鋳鋳片を製造する方法と、製造さ
れた表層と内層の成分濃度が異なる連鋳鋳片を提供する
ものである。Therefore, the present invention solves the above-mentioned problems, and even when producing a slab having a slab cross-sectional area of 500 cm 2 or less, the alloy is added from the continuous casting powder into the molten steel pool in the mold and the casting is performed. An object of the present invention is to provide a method for producing a continuous cast slab in which the alloy element concentration in only one surface layer portion is uniformly enriched, and a continuous cast slab in which the produced surface layer and the inner layer have different component concentrations.
【０００５】[0005]
【課題を解決するための手段】本発明は、上記課題を解
決するものであって、その要旨とするところは、次の
（１）、（２）及び（３）のとおりである。 （１）鋳片断面積が５００ｃｍ2 以下の鋳片を製造する
方法において、所定の合金元素を含有した連鋳パウダー
を用いると共に、連続鋳造鋳型内に電磁攪拌装置を設置
し、かつ、鋳型内に溶鋼を供給する浸漬ノズルの吐出孔
を前記攪拌装置のコイル中心位置よりも下方に位置せし
めることにより、鋳型内において、上部に、攪拌流によ
り前記合金元素が均一に溶解・混合した領域を形成し、
また、その下方に、合金元素の濃度が低い領域を形成す
ることで、合金元素の表層濃度が内層に比べて高い複層
状の鋳片を製造することを特徴とする連鋳鋳片の製造方
法。The present invention solves the above-mentioned problems, and its gist is as follows (1), (2) and (3). (1) In a method for producing a slab having a slab cross-sectional area of 500 cm 2 or less, a continuous casting powder containing a predetermined alloy element is used, an electromagnetic stirring device is installed in a continuous casting mold, and By positioning the discharge hole of the immersion nozzle for supplying molten steel below the center position of the coil of the stirring device, a region in which the alloy element is uniformly melted and mixed by the stirring flow is formed in the upper portion in the mold. ,
In addition, a method for producing a continuous cast slab, characterized in that a region having a low alloy element concentration is formed therebelow to produce a multilayer cast slab in which the surface layer concentration of the alloy element is higher than that of the inner layer. .
【０００６】（２）鋳片断面積が５００ｃｍ2 以下の鋳
片を製造する方法において、所定の合金元素を含有した
連鋳パウダーを用いると共に、連続鋳造鋳型内に電磁攪
拌装置を設置し、鋳型内溶鋼プール中の水平断面内で形
成する攪拌流の方向及び流速を周期的に切り替え、か
つ、鋳型内に溶鋼を供給する浸漬ノズルの吐出孔を前記
攪拌装置のコイル中心位置よりも下方に位置せしめ、鋳
型内において、上部に、攪拌流により前記合金元素が均
一に溶解・混合した領域を形成し、また、その下方に、
合金元素の濃度が低い領域を形成することで、合金元素
の表層濃度が内層に比べて高い複層状の鋳片を製造する
ことを特徴とする連鋳鋳片の製造方法。(2) In a method for producing a slab having a slab cross-sectional area of 500 cm 2 or less, a continuous casting powder containing a predetermined alloy element is used, and an electromagnetic stirring device is installed in the continuous casting mold, and The direction and flow rate of the stirring flow formed in the horizontal section in the molten steel pool are periodically switched, and the discharge hole of the immersion nozzle for supplying the molten steel into the mold is positioned below the coil center position of the stirring device. In the mold, a region in which the alloy element is uniformly dissolved and mixed by the agitated flow is formed at an upper portion, and below the lower portion,
A method for producing a continuous cast slab, wherein a region having a low alloy element concentration is formed to produce a multilayer cast slab having a surface layer concentration of an alloy element higher than that of an inner layer.
【０００７】（３）前記（１）または（２）の連鋳鋳片
の製造方法を用いて鋳造した、鋳片表層部の濃度が内層
濃度と比較して高く、かつ、その表層部の厚みが下記
（１）式で定義される厚みを有することを特徴とする連
鋳鋳片。 Ｄ＝ｋ（Ｌ／Ｖ）n …（１） Ｄ：表層部の厚み Ｌ：攪拌装置のコイル中心深さ Ｖ：鋳造速度 ｋ：凝固係数 ｎ：定数(3) The density of the surface layer portion of the slab cast using the method of producing a continuous cast slab according to the above (1) or (2) is higher than that of the inner layer, and the thickness of the surface layer portion Has a thickness defined by the following formula (1). D = k (L / V) n (1) D: thickness of surface layer L: depth of coil center of stirrer V: casting speed k: solidification coefficient n: constant
【０００８】[0008]
【発明の実施の形態】本発明において最も重要な点は、
鋳型内に溶鋼を注入する浸漬ノズルの吐出孔位置であ
る。そこで、以下、図２を例にとり、本発明を詳細に説
明する。断面積が５００ｃｍ2 以下のブルームや、ビレ
ット鋳造において、電磁攪拌装置３０のコイル中心位置
を湯面よりも数百ｍｍ下方（図中、Ｌ参照）に位置せし
め攪拌した場合、電磁攪拌装置３０のコイル中心位置を
境に上下に２つの循環流（図中、矢印参照）が形成さ
れ、コイル中心位置よりも上方に添加したものは上部溶
鋼プール３内で、一方、コイル中心位置よりも下方に添
加したものは下部溶鋼プール４内で、それぞれ均一に混
合されることを発明者らは見いだした。DESCRIPTION OF THE PREFERRED EMBODIMENTS The most important point in the present invention is that
This is the discharge hole position of the immersion nozzle for injecting molten steel into the mold. Therefore, the present invention will be described in detail below with reference to FIG. In a bloom or a billet casting having a cross-sectional area of 500 cm 2 or less, when the center position of the coil of the electromagnetic stirrer 30 is positioned several hundred mm below the molten metal surface (refer to L in the drawing) and stirred, the electromagnetic stirrer 30 Two circulating flows (see arrows in the figure) are formed vertically above and below the coil center position, and those added above the coil center position are in the upper molten steel pool 3 and, on the other hand, below the coil center position. The inventors have found that the additions are uniformly mixed in the lower molten steel pool 4 respectively.
【０００９】この知見に基づき、上部溶鋼プール３内に
合金元素を添加し、かつ、下部溶鋼プール４内にノズル
吐出孔を位置せしめ溶鋼を供給することにより、上部溶
鋼プール３と下部溶鋼プール４において成分濃度を違え
ることができ、その結果、合金濃度が表層と内層で異な
る鋳片を製造することができるのである。上部溶鋼プー
ル３に合金元素を添加する方法として、所定の合金元素
の粒あるいは粉１３を含有させた連鋳パウダー１０を用
い、連続的あるいは間欠的に、鋳型１上方から湯面全体
に添加する。そして、鋳型１内のメニスカス上で連鋳パ
ウダー１０が溶融していく過程で、上記合金元素の粒あ
るいは粉１３がメニスカスで溶鋼と接触し、メニスカス
より鋳型１内の上部溶鋼プール３中に混合・拡散する。
例えば、ニッケル、銅、炭素、マンガン、燐、硫黄、モ
リブデン等、酸化物の標準生成自由エネルギーが珪素、
硼素よりも大きい元素の合金粉あるいは金属粉であれ
ば、全て同じような形でパウダーから溶鋼中に添加する
ことができる。Based on this finding, the upper molten steel pool 3 and the lower molten steel pool 4 are added by adding an alloying element to the upper molten steel pool 3 and positioning the nozzle discharge hole in the lower molten steel pool 4 to supply molten steel. Therefore, the slabs having different alloy concentrations in the surface layer and the inner layer can be produced. As a method of adding an alloy element to the upper molten steel pool 3, a continuous cast powder 10 containing grains or powder 13 of a predetermined alloy element is used, and the alloy element is continuously or intermittently added from above the mold 1 to the entire molten metal surface. . Then, in the process of melting the continuous casting powder 10 on the meniscus in the mold 1, the grains or powders 13 of the alloy elements come into contact with the molten steel at the meniscus, and are mixed into the upper molten steel pool 3 in the mold 1 from the meniscus. ·Spread.
For example, nickel, copper, carbon, manganese, phosphorus, sulfur, molybdenum, etc., the standard free energy of formation of oxides is silicon,
All alloy powders or metal powders of elements larger than boron can be added from powder to molten steel in the same manner.
【００１０】ついで、鋳型１内の上部溶鋼プール３の濃
度分布を水平断面内で均一化させる必要があるが、その
ために本発明では、水平断面内で一方向の攪拌流３１を
形成するか、あるいは、その攪拌方向並びに攪拌流速を
周期的に時間変化させる。この２つの方式において、ど
ちらを選択するかは鋳造条件に応じて適宜選択すればよ
く、どちらかに限定されるものではないが、攪拌流速及
び攪拌方向を周期的に時間変化させる方式を用いた場
合、攪拌流に伴う湯面での乱れを発生させることなく、
パウダーからの合金添加を安定的に行うことができる。Next, it is necessary to make the concentration distribution of the upper molten steel pool 3 in the mold 1 uniform in the horizontal cross section. For this purpose, in the present invention, the unidirectional stirring flow 31 is formed in the horizontal cross section. Alternatively, the stirring direction and the stirring flow rate are periodically changed with time. In these two methods, which one to select may be appropriately selected according to the casting conditions, and is not limited to either, but a method in which the stirring flow rate and the stirring direction are periodically changed with time is used. In this case, without causing turbulence in the molten metal surface due to the stirring flow,
The alloy can be stably added from the powder.
【００１１】なお、攪拌方向及び攪拌流速を周期的に時
間変化させるには、図３に示すように、印加する電流を
周波数とは異なる周期で意図的に時間変化させる。この
時間変化により、鋳型１内の上部溶鋼プール３中の水平
断面内で振動攪拌流３２を付与することができる（図
４、参照）。攪拌方向及び攪拌流速が周期的に切り替わ
ることで、湯面での平均流速が小さくなり、湯面での乱
れが発生しなくなる。In order to periodically change the stirring direction and the stirring flow rate with time, as shown in FIG. 3, the applied current is intentionally changed with time at a cycle different from the frequency. By this time change, a vibrating stirring flow 32 can be applied in a horizontal section in the upper molten steel pool 3 in the mold 1 (see FIG. 4). By periodically switching the stirring direction and the stirring flow rate, the average flow rate on the surface of the molten metal becomes small, and the disturbance on the surface of the molten metal does not occur.
【００１２】さらに、その上部溶鋼プール３の下端であ
るコイル中心位置よりも下方に浸漬ノズル２の吐出孔を
位置せしめることにより、ノズル吐出流の合金元素の濃
度を上部溶鋼プール３の合金元素の濃度よりも低くする
ことができるので、ノズル吐出孔よりも下部溶鋼プール
４に合金元素濃度の低い溶鋼を供給することができる。
その結果、鋳片の表層部６では周方向に均一で、かつ、
鋳片の内層部７よりも合金元素の濃度が高い鋳片を製造
することができる。Further, by positioning the discharge hole of the immersion nozzle 2 below the center position of the coil which is the lower end of the upper molten steel pool 3, the concentration of the alloy element in the nozzle discharge flow can be reduced by the alloy element of the upper molten steel pool 3. Since the concentration can be lower than the concentration, molten steel having a lower alloy element concentration can be supplied to the lower molten steel pool 4 than the nozzle discharge hole.
As a result, the surface layer 6 of the slab is uniform in the circumferential direction, and
A slab having a higher alloy element concentration than the inner layer 7 of the slab can be manufactured.
【００１３】この際に、合金元素に応じ整粒化した粒あ
るいは粉１３を鋳片表層部６に添加したい成分濃度だけ
連鋳パウダー１０中に含有させれば、振動攪拌域内の溶
鋼成分を所定濃度の成分に調整することができる。な
お、この際、連鋳パウダー１０の粒内に、添加する合金
元素の粒あるいは粉を含有させると、合金添加をより均
一かつ安定化させることができる。At this time, if the continuous cast powder 10 contains the grain or powder 13 sized according to the alloying element in a concentration of a component desired to be added to the slab surface layer portion 6, the molten steel component in the vibration agitation zone is predetermined. The concentration can be adjusted to the components. In this case, when the grains or powder of the alloy element to be added are contained in the grains of the continuous casting powder 10, the addition of the alloy can be more uniform and stabilized.
【００１４】このようにして鋳造された鋳片は、以下の
特徴を有する。すなわち、鋳片の表層部の厚みについて
は、電磁攪拌装置のコイル中心位置よりも上に存在する
上部溶鋼プールで形成される凝固シェル厚みが表層部の
厚みとなるので、該表層部の厚みは下記（１）式で定義
される。 Ｄ＝ｋ（Ｌ／Ｖ）n …（１） Ｄ：表層部の厚み Ｌ：電磁攪拌装置のコイル中心深さ Ｖ：鋳造速度 ｋ：凝固係数 ｎ：定数The slab thus cast has the following characteristics. That is, as for the thickness of the surface layer portion of the slab, the thickness of the solidified shell formed in the upper molten steel pool existing above the center position of the coil of the electromagnetic stirrer becomes the thickness of the surface layer portion. It is defined by the following equation (1). D = k (L / V) n (1) D: thickness of surface layer L: depth of coil center of electromagnetic stirrer V: casting speed k: solidification coefficient n: constant
【００１５】[0015]
【実施例】鋳型１内の湯面レベルから３００ｍｍ下方に
電磁攪拌装置３０の高さ方向中心を位置せしめ、鋳型１
内の上部溶鋼プール３の中に、水平断面内で攪拌流３１
を付与できるようにした連鋳プロセス（図２、参照）に
おいて、表１に示す条件で鋳造を行った。鋳型１内に溶
鋼を供給する浸漬ノズル２のノズル吐出孔位置は湯面レ
ベルからノズル吐出孔まで２００ｍｍ、３００ｍｍ、及
び、４００ｍｍ（図中、Ｌ）とした。EXAMPLE The center of the electromagnetic stirrer 30 in the height direction was positioned 300 mm below the level of the molten metal in the mold 1.
In the upper molten steel pool 3 inside, the agitated flow 31
In the continuous casting process (see FIG. 2) in which casting was performed, casting was performed under the conditions shown in Table 1. The positions of the nozzle discharge holes of the immersion nozzle 2 for supplying the molten steel into the mold 1 were 200 mm, 300 mm, and 400 mm (L in the figure) from the level of the molten metal to the nozzle discharge holes.
【００１６】また、パウダー中にニッケル粉を２０質量
％含有させ、鋳型上方から湯面全体に亘って、鋳造中、
連続的に供給した。なお、攪拌方式については、一方向
の攪拌流を付与した場合、及び攪拌方向及び攪拌流速を
周期的に切り替えた場合について実験を行った。図５
は、電磁攪拌のみを印加した場合の鋳片内でのニッケル
濃度分布を示すものであり、（ａ）は、幅方向中心での
鋳片厚み方向のニッケル濃度分布を示し、（ｂ）は、表
面から５ｍｍでの鋳片周方向のニッケル濃度分布を示す
ものである。この図５より、ノズル吐出孔位置を電磁攪
拌装置のコイル中心位置よりも下方に位置せしめた場合
においては、鋳片表層のニッケル濃度が周方向全体に亘
って、鋳片内層部よりも高くなっていることがわかる。Further, the powder contains 20% by mass of nickel powder, and is cast over the entire surface of the molten metal from above the mold.
Feeded continuously. In addition, regarding the stirring method, an experiment was performed when a unidirectional stirring flow was applied and when the stirring direction and the stirring flow rate were periodically switched. FIG.
Shows the nickel concentration distribution in the slab when only electromagnetic stirring is applied, (a) shows the nickel concentration distribution in the slab thickness direction at the center in the width direction, and (b) shows It shows the nickel concentration distribution in the slab circumferential direction at 5 mm from the surface. From FIG. 5, when the position of the nozzle discharge hole is positioned below the center position of the coil of the electromagnetic stirrer, the nickel concentration of the slab surface layer is higher than the slab inner layer portion over the entire circumferential direction. You can see that it is.
【００１７】図６は、一方向の攪拌流を付与した場合
と、振動攪拌流を付与した場合について、鋳片のニッケ
ル濃度分布を比較したものである。なお、図の縦軸は、
鋳片表層部におけるニッケル濃度の周方向平均値からの
ずれ（標準偏差）を平均的な富化濃度で割った値であ
り、この値が小さいほど濃度分布が周方向に均一である
ことを意味している。攪拌流速を速くした場合におい
て、一方向に攪拌した場合、鋳片表層部のニッケル濃度
分布に不均一が見られるが、低攪拌流速の場合、両者の
差はそれほど顕著には認められない。FIG. 6 shows a comparison of the nickel concentration distribution of the slab when a unidirectional stirring flow is applied and when a vibrating stirring flow is applied. The vertical axis of the figure is
It is a value obtained by dividing the deviation (standard deviation) of the nickel concentration in the surface layer of the slab from the circumferential average value by the average enrichment concentration. The smaller this value is, the more uniform the concentration distribution is in the circumferential direction. are doing. When the stirring speed is increased, when the stirring is performed in one direction, the nickel concentration distribution in the surface layer portion of the slab is not uniform, but when the stirring speed is low, the difference between the two is not so remarkably recognized.
【００１８】また、炭素、マンガン、燐、硫黄、銅、ク
ロム、モリブデン、ニオブについて同様な実験をしたと
ころ、どの元素においても、表層部の合金元素の濃度が
内層部と比較して高く、かつ、鋳片幅方向に一様な濃度
分布の鋳片を得ることができた。Similar experiments were conducted on carbon, manganese, phosphorus, sulfur, copper, chromium, molybdenum, and niobium. As a result, the concentration of the alloying element in the surface layer was higher than that in the inner layer, and the concentration of the alloying element was higher than that of the inner layer. Thus, a slab having a uniform concentration distribution in the slab width direction could be obtained.
【００１９】[0019]
【表１】 [Table 1]
【００２０】[0020]
【発明の効果】本発明の連鋳鋳片の製造方法によれば、
鋳片断面積が５００ｃｍ2 以下の鋳片を製造する方法に
おいて、合金元素を含む連鋳パウダーを用い、電磁攪拌
装置を用い鋳型内溶鋼プール中で攪拌流を付与するか、
あるいは、流れの方向が周期的に変化する振動攪拌流を
付与し、合金元素を溶解・混合する領域を形成し、か
つ、浸漬ノズルの吐出孔を電磁攪拌装置のコイル中心位
置よりも下方に位置せしめて合金元素の濃度が低い領域
を形成することにより、合金元素の表層濃度が内層に比
べて高く、かつ、表層部の合金元素の濃度が均一な複層
状の鋳片を製造することができる。According to the method for producing a continuous cast slab of the present invention,
In a method for producing a slab having a slab cross-sectional area of 500 cm 2 or less, using a continuous casting powder containing an alloy element, or applying a stirring flow in a molten steel pool in a mold using an electromagnetic stirring device,
Alternatively, a vibrating stirring flow in which the flow direction changes periodically is provided to form a region for dissolving and mixing the alloy element, and the discharge hole of the immersion nozzle is positioned below the center position of the coil of the electromagnetic stirring device. By forming at least the region where the concentration of the alloying element is low, it is possible to manufacture a multilayer slab in which the surface concentration of the alloying element is higher than that of the inner layer and the concentration of the alloying element in the surface portion is uniform. .
【００２１】すなわち、本発明によれば、例えば、銅と
錫、あるいは、銅のみを含有した鋼の鋳造において、鋳
片の表層部のニッケル濃度を高くすることにより、この
鋼種に特有の銅起因の表面きずを抑制することができ
る。その他、鋳片表層部の濃度を、スケールきずや割れ
きず、メッキ不良等の様々な欠陥が発生しないレベルの
濃度に意図的に高めることができるので、鋳造段階にお
いて、鋳造以降の過程で発生する欠陥を防止することが
できる。加えて、鋳片表層部に新しい機能を付与した鋳
片を簡便に製造することができる。さらに、本発明は、
鋳片サイズによらず適用できる。例えば、ブルーム、ビ
レットのような小断面サイズの鋳造、あるいは、厚みが
１００ｍｍ以下の薄スラブ鋳造にも適用可能である。That is, according to the present invention, for example, in the casting of steel containing copper and tin, or only copper, by increasing the nickel concentration in the surface layer of the slab, the copper origin specific to this steel type is obtained. Surface flaws can be suppressed. In addition, since the concentration of the surface layer of the slab can be intentionally increased to a level at which various defects such as scale flaws and cracks and poor plating do not occur, it occurs in the casting stage and in the process after casting. Defects can be prevented. In addition, a slab having a new function added to the slab surface layer can be easily manufactured. Further, the present invention provides
Applicable regardless of slab size. For example, the present invention can be applied to casting of a small cross-sectional size such as bloom and billet, or casting of a thin slab having a thickness of 100 mm or less.
【図面の簡単な説明】[Brief description of the drawings]
【図１】電磁攪拌装置を用い一方向の攪拌流を形成する
従来の連続鋳造を例示する図である。（ａ）は、鋳型上
方からみた鋳型内の状況を示し、（ｂ）は、鋳型内の溶
鋼プール中の鉛直断面構造を示し、（ｃ）は、鋳片の水
平断面での合金元素の濃度分布の状況を示す。FIG. 1 is a diagram illustrating a conventional continuous casting for forming a unidirectional stirring flow using an electromagnetic stirring device. (A) shows the situation in the mold as viewed from above the mold, (b) shows the vertical cross-sectional structure in the molten steel pool in the mold, and (c) shows the concentration of the alloy element in the horizontal cross section of the slab. Shows the distribution situation.
【図２】一方向の攪拌流を付与し、下向き１孔型の浸漬
ノズルを用いる本発明の連続鋳造を例示する図である。
（ａ）は、鋳型上方からみた鋳型内の状況を示し、
（ｂ）は、鋳型内の溶鋼プール中の鉛直断面構造を示
し、（ｃ）は、鋳片の水平断面での合金元素の濃度分布
の状況を示す。FIG. 2 illustrates a continuous casting of the present invention using a downward one-hole immersion nozzle with a unidirectional stirring flow.
(A) shows the situation in the mold as seen from above the mold,
(B) shows the vertical cross-sectional structure in the molten steel pool in the mold, and (c) shows the state of the concentration distribution of the alloy element in the horizontal cross section of the slab.
【図３】電磁攪拌装置に印加する電流の時間変化
（ａ）、及び、コイル中心高さにおける凝固シェル前面
の流速の時間変化（ｂ）を、それぞれ示す図である。FIG. 3 is a diagram showing a time change (a) of a current applied to an electromagnetic stirring device and a time change (b) of a flow velocity on the front surface of a solidified shell at the height of a coil center.
【図４】印加する周波数とは異なる周期で攪拌流の方向
及び流速を時間変化する振動攪拌流を付与し下向き１孔
型の浸漬ノズルを用いる本発明の連続鋳造を例示する図
である。（ａ）は、鋳型上方からみた鋳型内の状況を示
し、（ｂ）は、鋳型内の溶鋼プール中の鉛直断面構造を
示し、（ｃ）は、鋳片水平断面での合金元素の濃度分布
の状況を示す。FIG. 4 is a view exemplifying continuous casting of the present invention using a downward one-hole immersion nozzle by applying a vibrating agitating flow that changes the direction and flow velocity of the agitating flow with time at a cycle different from the frequency of application. (A) shows the situation in the mold as viewed from above the mold, (b) shows the vertical sectional structure in the molten steel pool in the mold, and (c) shows the concentration distribution of alloy elements in the horizontal section of the slab. Shows the situation.
【図５】ノズル吐出孔位置を変えて電磁攪拌のみを印加
した場合における、鋳片厚み方向及び鋳片周方向のニッ
ケル濃度分布を示す図である。FIG. 5 is a diagram showing a nickel concentration distribution in a slab thickness direction and a slab circumferential direction when only electromagnetic stirring is applied while changing the nozzle discharge hole position.
【図６】一方向の攪拌流を付与した場合と振動攪拌流を
付与した場合における、攪拌流速と鋳片表層部ニッケル
濃度の関係を示す図である。FIG. 6 is a diagram showing the relationship between the stirring flow rate and the nickel concentration in the surface layer of the slab when a unidirectional stirring flow is applied and when a vibration stirring flow is applied.
１…鋳型 ２…浸漬ノズル ３…上部溶鋼プール ４…下部溶鋼プール ６…鋳片の表層部 ７…鋳片の内層部 ９…攪拌域 １０…連鋳パウダー １３…合金元素の粒あるいは粉 ３０…電磁攪拌装置 ３１…攪拌流 ３２…振動攪拌流 DESCRIPTION OF SYMBOLS 1 ... Mold 2 ... Immersion nozzle 3 ... Upper molten steel pool 4 ... Lower molten steel pool 6 ... Surface layer of cast piece 7 ... Inner layer part of cast piece 9 ... Stir zone 10 ... Continuous casting powder 13 ... Grain or powder of alloy element 30 ... Electromagnetic stirrer 31: Stirring flow 32: Vibration stirring flow
フロントページの続き (72)発明者 安斎 栄尚 北海道室蘭市仲町12番地 新日本製鐵株式 会社室蘭製鐵所内 Ｆターム(参考） 4E004 AA09 MB12 MB14 NA01 NB02 NC01 Continuation of the front page (72) Inventor Eisai Ansai 12 Nakamachi, Muroran-shi, Hokkaido F-term (reference) in Nippon Steel Corporation Muroran Works 4E004 AA09 MB12 MB14 NA01 NB02 NC01
Claims (3)
製造する方法において、所定の合金元素を含有した連鋳
パウダーを用いると共に、連続鋳造鋳型内に電磁攪拌装
置を設置し、かつ、鋳型内に溶鋼を供給する浸漬ノズル
の吐出孔を前記攪拌装置のコイル中心位置よりも下方に
位置せしめることにより、鋳型内において、上部に、攪
拌流により前記合金元素が均一に溶解・混合した領域を
形成し、また、その下方に、合金元素の濃度が低い領域
を形成することで、合金元素の表層濃度が内層に比べて
高い複層状の鋳片を製造することを特徴とする連鋳鋳片
の製造方法。1. A method for producing a slab having a slab cross-sectional area of 500 cm 2 or less, wherein a continuous casting powder containing a predetermined alloy element is used, an electromagnetic stirring device is installed in a continuous casting mold, and By positioning the discharge hole of the immersion nozzle for supplying molten steel below the center position of the coil of the stirrer, in the mold, the region where the alloy element is uniformly melted and mixed by the stir flow in the upper part of the mold Forming a continuous cast slab characterized by producing a multi-layer cast slab having a lower alloy element surface concentration than the inner layer by forming a region below the alloy element concentration below the same. Manufacturing method.
製造する方法において、所定の合金元素を含有した連鋳
パウダーを用いると共に、連続鋳造鋳型内に電磁攪拌装
置を設置し、鋳型内溶鋼プール中の水平断面内で形成す
る攪拌流の方向及び流速を周期的に切り替え、かつ、鋳
型内に溶鋼を供給する浸漬ノズルの吐出孔を前記攪拌装
置のコイル中心位置よりも下方に位置せしめ、鋳型内に
おいて、上部に、攪拌流により前記合金元素が均一に溶
解・混合した領域を形成し、また、その下方に、合金元
素の濃度が低い領域を形成することで、合金元素の表層
濃度が内層に比べて高い複層状の鋳片を製造することを
特徴とする連鋳鋳片の製造方法。2. A method for producing a slab having a slab cross-sectional area of 500 cm 2 or less, wherein a continuous casting powder containing a predetermined alloy element is used and an electromagnetic stirring device is installed in the continuous casting mold. Periodically switch the direction and flow velocity of the stirring flow formed in the horizontal cross section in the pool, and position the discharge hole of the immersion nozzle that supplies molten steel into the mold below the coil center position of the stirring device, In the mold, a region in which the alloy element is uniformly dissolved and mixed by an agitated flow is formed at an upper portion, and a region having a lower alloy element concentration is formed below the upper portion so that the surface layer concentration of the alloy element is lower. A method for producing a continuous cast slab, characterized by producing a multi-layer cast slab higher than an inner layer.
方法を用いて鋳造した、鋳片表層部の濃度が内層濃度と
比較して高く、かつ、その表層部の厚みが下記（１）式
で定義される厚みを有することを特徴とする連鋳鋳片。 Ｄ＝ｋ（Ｌ／Ｖ）n …（１） Ｄ：表層部の厚み Ｌ：コイル中心深さ Ｖ：鋳造速度 ｋ：凝固係数 ｎ：定数3. A cast slab produced by the method according to claim 1 or 2, wherein the concentration of the surface layer of the slab is higher than that of the inner layer, and the thickness of the surface layer is as follows: 1) A continuous cast slab having a thickness defined by the formula. D = k (L / V) n (1) D: thickness of surface layer L: depth of coil center V: casting speed k: solidification coefficient n: constant
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000142522A JP2001321907A (en) | 2000-05-15 | 2000-05-15 | Method for producing continuous casting slab and continuous casting slab |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000142522A JP2001321907A (en) | 2000-05-15 | 2000-05-15 | Method for producing continuous casting slab and continuous casting slab |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2001321907A true JP2001321907A (en) | 2001-11-20 |
Family
ID=18649464
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2000142522A Withdrawn JP2001321907A (en) | 2000-05-15 | 2000-05-15 | Method for producing continuous casting slab and continuous casting slab |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2001321907A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008018449A (en) * | 2006-07-12 | 2008-01-31 | Kobe Steel Ltd | Method for managing immersed nozzle |
| CN104942247A (en) * | 2014-03-31 | 2015-09-30 | 北京明诚技术开发有限公司 | Control system and method for regulating electromagnetic stirrer in continuous casting process |
| CN106756193A (en) * | 2016-12-30 | 2017-05-31 | 苏州有色金属研究院有限公司 | Preparation facilities of carbon nanotube enhanced aluminium-based composite material and preparation method thereof |
-
2000
- 2000-05-15 JP JP2000142522A patent/JP2001321907A/en not_active Withdrawn
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008018449A (en) * | 2006-07-12 | 2008-01-31 | Kobe Steel Ltd | Method for managing immersed nozzle |
| CN104942247A (en) * | 2014-03-31 | 2015-09-30 | 北京明诚技术开发有限公司 | Control system and method for regulating electromagnetic stirrer in continuous casting process |
| CN106756193A (en) * | 2016-12-30 | 2017-05-31 | 苏州有色金属研究院有限公司 | Preparation facilities of carbon nanotube enhanced aluminium-based composite material and preparation method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP6855806B2 (en) | Continuous casting method and continuous casting equipment for multi-layer slabs | |
| JP2017080788A (en) | Method and device for continuously casting double-layered cast slab | |
| US6557623B2 (en) | Production method for continuous casting cast billet | |
| JP2001321907A (en) | Method for producing continuous casting slab and continuous casting slab | |
| WO1993022085A1 (en) | Method of obtaining double-layered cast piece | |
| JP3456311B2 (en) | Continuous casting method of multilayer slab | |
| JP2001232450A (en) | Method for manufacturing continuous cast slab | |
| JP2017196626A (en) | Continuous casting method for molten steel | |
| JP6500682B2 (en) | Method and apparatus for continuous casting of multi-layer cast slab | |
| JP2001300704A (en) | Method for producing continuously cast slat and cast slab | |
| JP3257546B2 (en) | Steel continuous casting method | |
| JP3573096B2 (en) | Manufacturing method of continuous cast slab | |
| JPH08290235A (en) | Production of continuously cast slab | |
| JPH09122833A (en) | Method for concentrating solute on surface layer of cast slab in continuous casting | |
| JP2018069324A (en) | Mold device for continuous casting for steel and manufacturing method of surface layer-modified cast slab using the same | |
| RU2419508C2 (en) | Mixer | |
| JPH0924445A (en) | Method for concentrating solute on surface layer of cast slab in continuous casting | |
| JP3426383B2 (en) | Steel continuous casting method | |
| JPH0839196A (en) | Production of continuously cast slab | |
| JP2002178108A (en) | Method for continuously casting steel | |
| JPH08290236A (en) | Production of continuously cast slab | |
| JPH11320050A (en) | Continuous casting method | |
| JPH08300111A (en) | Method for continuously casting small lot of cast slab | |
| JP2002205152A (en) | Method for producing continuously cast product | |
| JPH07290195A (en) | Production of continuously cast slab |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20070807 |