JPH0320295B2 - - Google Patents
Info
- Publication number
- JPH0320295B2 JPH0320295B2 JP25289886A JP25289886A JPH0320295B2 JP H0320295 B2 JPH0320295 B2 JP H0320295B2 JP 25289886 A JP25289886 A JP 25289886A JP 25289886 A JP25289886 A JP 25289886A JP H0320295 B2 JPH0320295 B2 JP H0320295B2
- Authority
- JP
- Japan
- Prior art keywords
- slab
- mold
- magnetic field
- composite metal
- static magnetic
- 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
Links
- 239000002184 metal Substances 0.000 claims description 49
- 229910052751 metal Inorganic materials 0.000 claims description 49
- 230000003068 static effect Effects 0.000 claims description 29
- 239000002131 composite material Substances 0.000 claims description 24
- 239000007769 metal material Substances 0.000 claims description 22
- 239000002344 surface layer Substances 0.000 claims description 20
- 150000002739 metals Chemical class 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 12
- 238000007711 solidification Methods 0.000 claims description 9
- 230000008023 solidification Effects 0.000 claims description 9
- 238000009749 continuous casting Methods 0.000 claims description 8
- 230000004907 flux Effects 0.000 claims description 7
- 238000005266 casting Methods 0.000 description 25
- 239000010410 layer Substances 0.000 description 23
- 238000002347 injection Methods 0.000 description 6
- 239000007924 injection Substances 0.000 description 6
- 238000005192 partition Methods 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 238000007654 immersion Methods 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 4
- 239000010935 stainless steel Substances 0.000 description 4
- 229910001220 stainless steel Inorganic materials 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 238000007796 conventional method Methods 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000011819 refractory material Substances 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- 229910000954 Medium-carbon steel Inorganic materials 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 239000003245 coal Substances 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 229910001338 liquidmetal Inorganic materials 0.000 description 1
- 239000000155 melt Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- -1 that is Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Description
（産業上の利用分野）
本発明は、表層部と内層部の組成、すなわち化
学成分の異なる金属鋳片（複合金属材）を液状金
属から連続的に製造する方法に関するものであ
る。
（従来の技術）
従来、連続鋳造によつて複合金属材を製造する
方法として、例えば特公昭44−27361号公報に開
示されているような、２本の長さの異なる浸漬ノ
ズルを鋳型内金属溶湯プール内に挿入し、それぞ
れのノズルの吐出孔位置を鋳造方向の異なる位置
に設けて異種の溶湯金属を注入する方法（第３図
に示す）が知られている。
第３図において、１１は鋳型、１２，１３はそ
れぞれ浸漬ノズルであつて長さが相違し、それぞ
れ異種金属を鋳型１１内に注入する。１４は鋳型
内溶融金属プール、１５は複合金属材の表層部、
１６は複合金属材の内層凝固部である、
しかしながら、単に２本の浸漬ノズルで鋳型内
の鋳造方向の異なる位置で異種金属を注入するよ
うにしただけの方法では、異種金属の鋳型内にお
ける吐出位置或は吐出流のパターンを如何に調整
しようとも、注入の進行、つまり鋳造の進行とと
もに溶融金属間での混合が生じ、鋳造行の鋳片の
表層から内部にかけて、厚さ方向において濃度が
均一化された、或は表層と内層の境界が極めて不
明瞭な鋳片となり、目的とする本来の表層と内層
の境界の明瞭な複合金属材を得ることができない
という問題がある。
かかる問題とを解決すべく、特公昭49−44859
号公報には、第２図に示すような、鋳型内異種金
属間に耐火物製隔壁を設けて連続鋳造するプロセ
スが提案されている。
第２図において、２１は鋳型、２２，２３はそ
れぞれ浸漬ノズルであつて長さが相違し、それぞ
れ異種金属を鋳型２１内に注入する。２４は鋳型
内溶融金属プール、２５は複合金属材の表層部、
２６は複合金属材の内層凝固部、２７は耐火物製
隔壁である。
しかしながら、連続鋳造ストランドの溶融金属
プール内に、異種溶融金属の混合を抑えるために
十分な大きさの耐火物を挿入することは鋳造操業
上大きな問題を有する。すなわち、耐火物製隔壁
が凝固中のシエルに接すると、このシエルに捕捉
され耐火物が破損したり、シエルが破れて溶融金
属がストランド外に流出する事態（ブレークアウ
ト）となる危険性が高い。
また、鋳型内の耐火物製隔壁が高温の溶融金
属、例えば溶鋼中に浸漬された場合は、物理的強
度の点でも問題であり、鋳造中に溶損或は破損し
て本来の目的が達成できないばかりか、ストラン
ド中に巻き込まれた耐火物は鋳造作業上また品質
上重大なトラブルとなる。
（発明が解決しようとする問題点）
この発明は、上に述べた従来の技術における問
題点を解決し、すぐれた品質の複合金属材を安定
した操業下に連続鋳造によつて得る方法を提出す
ることを目的としてなされた。
（問題点を解決するための手段）
本発明は、鋳型内湯面レベルから(1)式によつて
定まる距離ｌだけ下方の位置を中心とし、かつそ
の上下に一定の幅を有する領域において、鋳片の
厚みを横切る方向の直流磁束を鋳片全幅に亙つて
付与するとともに、該直流磁束によつて形成され
る静磁場帯を境界としてその上下に組成の異なる
金属を供給することを特徴とする複合金属材の連
続鋳造方法である。
ｌ＝dv／ｆ ……(1)
ここで、ｌ：鋳型内湯面レベルからの距離
ｄ：複合金属鋳片の表層厚み
ｖ：鋳片の引抜速度
ｆ：鋳片の平均凝固速度
上下いずれかの金属成分を、供給する金属ワイ
ヤーによつて調整することも可能である。
（作用）
以下に、本発明を詳細に説明する。
本発明にあつては、従来の技術における問題を
根本的に解決するために、鋳型内における異なる
組成の溶融金属を磁気的手段によつて分離し、こ
の境界の上下にそれぞれ組成の異なる溶融金属を
供給する。かくすることにより、先に凝固する鋳
型内上部（即ち凝固した鋳片における表層部）と
それに続いて凝固する下部（凝固後の鋳片におけ
る内層部）の境界が明瞭な、即ち両層間の濃度の
遷移層が薄い複合金属材を得ることができる。
本発明者等は、従来の技術における問題を解決
すべく種々研究を重ねた結果、鋳型内の相対的に
上部の溶融金属供給位置と相対的に下部の溶融金
属供給位置との間に、鋳片の厚みを横切る方向の
直流磁束を鋳片全幅に亙つて付与して静磁場帯を
形成させることにより、供給位置の異なる組成の
異なる金属が混合するのをよりよく防ぐことがで
きることを見出した。
この発明は、以上の知見を基礎に完成されたも
のであるが、この発明を実施するための装置の一
例を第１図ａ，ｂに示す。
第１図ａ，ｂにおいて、１は鋳型、２，３はそ
れぞれ浸漬ノズルであつて長さが相違し、それぞ
れ組成の異なる溶融金属を鋳型１内に注入する。
４は溶融金属プール、５は複合金属材の表層部、
６は複合金属材の内層凝固部である。８は磁石で
あつて、鋳造方向(A)に垂直な方向、即ち、鋳片の
厚みを横切る方向に直流磁束を付与して静磁場を
形成する。９は複合金属材である。
ここで、第５図において、鋳片の引抜速度が
ｖ、鋳片の平均凝固速度がｆなる鋳造条件下で、
所定の鋳片表層厚みｄを得るための、鋳型内溶融
金属上部プール３０の深さ、すなわち凝固開始位
置である溶湯湯面３１から静磁場帯３２の中心位
置３３までの距離ｌは次式によつて示される。
ｌ＝dv／ｆ ……(1)
この式は次のように導かれる。
上部プール３０の溶融金属のうち、静磁場帯の
中心位置３３まで降下する過程で凝固した鋳型接
触部分が厚みｄの鋳片表層を形成する。従つて、
前記の距離ｌを鋳造速度ｖで引抜かれるのに要す
る時間は、ｌ／ｖで表される。
一方、溶融金属の平均凝固速度はｆなので、静
磁場帯の中心位置３３における鋳片表層の凝固シ
エル厚みｄは、
ｄ＝ｆ×（ｌ／ｖ）
で表され、この式から、前記(1)式が得られる。
このようにして設定された鋳型内湯面レベルか
ら距離ｌだけ下方の位置に、鋳片全幅に亘つて、
鋳造方向に一定の幅を以て、鋳片の厚みを横切る
方向に直流磁束を付与して所定強度の静磁場を形
成し、注入によつて引き起こされる溶融金属プー
ル内の流れをこの静磁場の部分で制動させること
によつて上下層が接する位置での上下層の混合を
最低限に抑え得る。
その際、磁場の強度は、鋳造作業に支障を来さ
ない範囲内で強いほど溶融金属流動に対する制動
力は強く、静磁場帯の鋳造方向の幅も広いほど制
動力は強いが、この静磁場帯の幅が上下層の遷移
層となる場合もあり、この観点から静磁場帯の鋳
造方向の幅は、広ければよいというものではな
い。
電導性を有する流体が静磁場中を動くとき流速
が減衰する現象は電磁制動として古くから知られ
ている事実であるが、本発明はこの制動力が働く
位置を鋳造方向のある位置に設定し、それを境に
して異なる組成の溶融金属をその上部と下部に供
給して複合金属材を得ると共に、上記位置の設定
場所によつて表層の厚みをコントロールするとい
う製造プロセスを対象としている。この静磁場を
発生させるために電磁石を使用してもよく、また
永久磁石を用いてもよい。
また上部と下部の凝固量に見合うように各ノズ
ルからの注入量をコントロールする事は、静磁場
の効果と共に混合を抑えるために必要不可欠であ
る。すなわち静磁場によつて両層の混合を抑えて
おきながら両種の溶融金属の注入量比が変動した
場合、静磁場帯の中の変動であつても少なからず
境界部での混合をもたらし、ましてや静磁場帯の
外に境界がずれるともはや混合の抑制は期待でき
ない。また、この注入量比の変動自体が混合を促
進する事になる。従つて、鋳造方向にある一定の
幅を有する静磁場帯を設けることにより、少しで
もこれらの混合要因に対する対策を講じておく必
要ががある。この幅としては、できれば20cm以上
（すなわち中心位置±10cm以上）は設けることが
好ましい。もし、20cmよりも幅が狭いと、前記の
注入量比が変動した場合に、静磁場帯の外に境界
がずれる可能性が大きくなる。
さらに、本発明者らは、たとえば第６図のよう
に、上部プールあるいは下部プールのうちいずれ
か一方のプールに所定の合金元素をワイヤーにて
供給添加することにより、そのプールの溶湯の合
金成分濃度を調整しつつ、静磁場帯によつて上部
プールと下部プールとの混合を抑えて鋳造し、目
的とする表層成分及び内層成分からなる複合金属
材を得ることができることを確認した。
なお、ワイヤーによる下部プールへの合金元素
添加に当たつては、ワイヤーが湯面から挿入され
るため、上部プールにおいて溶解してしまう可能
性がある。そこで、コノワイヤー溶解を防ぐた
め、上部プールでは溶解せず、下部プールで溶解
するように設計された被覆ワイヤーを用いるのが
効果的である。その様子の一例を第６図に示す。
この場合には、被覆ワイヤー３５を下部プール３
４に挿入添加しており、ここでワイヤー３５を溶
解させて所定の濃度とすることができる。ワイヤ
ーを上部プールに供給する場合には特に被覆ワイ
ヤーとする必要はない。
（実施例）
表１に示すような18−８ステンレス鋼、一
般中炭鋼の２種類の溶鋼を別々のタンデイシユに
保持し、別々の浸漬ノズルを用いてを上部に、
を下部に注入した。
(Industrial Application Field) The present invention relates to a method for continuously producing metal slabs (composite metal materials) whose surface layer portion and inner layer portion have different compositions, that is, chemical components, from liquid metal. (Prior art) Conventionally, as a method for manufacturing composite metal materials by continuous casting, two immersion nozzles of different lengths are used to cast metal in a mold, as disclosed in Japanese Patent Publication No. 44-27361, for example. There is a known method (shown in FIG. 3) in which different types of molten metal are injected by inserting the molten metal into a molten metal pool and setting the discharge holes of the respective nozzles at different positions in the casting direction. In FIG. 3, 11 is a mold, and 12 and 13 are submerged nozzles of different lengths, respectively, for injecting different metals into the mold 11. 14 is the molten metal pool in the mold, 15 is the surface layer of the composite metal material,
16 is the inner layer solidification part of the composite metal material. However, with a method in which dissimilar metals are simply injected at different positions in the casting direction within the mold using two immersion nozzles, discharging of dissimilar metals within the mold is difficult. No matter how the position or discharge flow pattern is adjusted, as the injection progresses, that is, the casting progresses, mixing occurs between the molten metals, and the concentration is uniform in the thickness direction from the surface layer to the inside of the slab in the casting row. There is a problem in that the resulting slab has a very unclear boundary between the surface layer and the inner layer, and it is not possible to obtain the desired composite metal material with a clear boundary between the surface layer and the inner layer. In order to solve this problem, Special Publication No. 49-44859
The publication proposes a continuous casting process in which refractory partition walls are provided between dissimilar metals in a mold, as shown in FIG. In FIG. 2, 21 is a mold, and 22 and 23 are submerged nozzles of different lengths, respectively, for injecting different metals into the mold 21. 24 is the molten metal pool in the mold, 25 is the surface layer of the composite metal material,
26 is an inner solidified portion of the composite metal material, and 27 is a partition wall made of refractory material. However, inserting a refractory of sufficient size into the molten metal pool of a continuously cast strand to suppress mixing of dissimilar molten metals poses a major problem in casting operations. In other words, if a refractory partition wall comes into contact with a solidifying shell, there is a high risk that the refractory will be trapped by the shell and the refractory will be damaged, or that the shell will rupture and the molten metal will flow out of the strand (breakout). . In addition, if the refractory partition walls in the mold are immersed in high-temperature molten metal, such as molten steel, there is a problem in terms of physical strength, and the original purpose may not be achieved due to melting or damage during casting. Not only is this not possible, but the refractory caught in the strand will cause serious problems in terms of casting work and quality. (Problems to be Solved by the Invention) This invention solves the problems in the conventional techniques described above and proposes a method for obtaining composite metal materials of excellent quality by continuous casting under stable operation. It was done with the purpose of (Means for Solving the Problems) The present invention provides a method for forming a mold in an area centered at a position below the level of the molten metal in the mold by a distance l determined by equation (1) and having a constant width above and below the It is characterized by applying DC magnetic flux in a direction across the thickness of the slab over the entire width of the slab, and supplying metals with different compositions above and below the static magnetic field zone formed by the DC magnetic flux. This is a continuous casting method for composite metal materials. l=dv/f...(1) where, l: Distance from the level of the molten metal in the mold d: Surface layer thickness of the composite metal slab v: Drawing speed of the slab f: Average solidification rate of the slab Either upper or lower It is also possible to adjust the metal component via the supplied metal wire. (Function) The present invention will be explained in detail below. In order to fundamentally solve the problems in the conventional technology, the present invention separates molten metals of different compositions in a mold by magnetic means, and separates molten metals of different compositions above and below this boundary. supply. By doing this, there is a clear boundary between the upper part of the mold that solidifies first (i.e., the surface layer of the solidified slab) and the lower part that solidifies subsequently (the inner layer of the slab after solidification), that is, the concentration between the two layers. A composite metal material with a thin transition layer can be obtained. As a result of various studies to solve the problems in the conventional technology, the inventors of the present invention discovered that a mold is placed between the relatively upper molten metal supply position and the relatively lower molten metal supply position in the mold. It was discovered that mixing of different metals with different compositions at the feeding position can be better prevented by applying DC magnetic flux in the direction across the thickness of the slab to form a static magnetic field band over the entire width of the slab. . This invention was completed based on the above knowledge, and an example of an apparatus for carrying out this invention is shown in FIGS. 1a and 1b. In FIGS. 1a and 1b, 1 is a mold, and 2 and 3 are submerged nozzles having different lengths, and each molten metal having a different composition is injected into the mold 1. In FIGS.
4 is a molten metal pool, 5 is a surface layer of a composite metal material,
6 is the inner layer solidified portion of the composite metal material. Reference numeral 8 denotes a magnet which applies a DC magnetic flux in a direction perpendicular to the casting direction (A), that is, in a direction across the thickness of the slab to form a static magnetic field. 9 is a composite metal material. Here, in FIG. 5, under casting conditions where the slab drawing speed is v and the average solidification rate of the slab is f,
In order to obtain a predetermined slab surface layer thickness d, the depth of the molten metal upper pool 30 in the mold, that is, the distance l from the molten metal surface 31, which is the solidification start position, to the center position 33 of the static magnetic field zone 32 is calculated by the following formula. It is indicated by l=dv/f...(1) This equation is derived as follows. The part of the molten metal in the upper pool 30 that comes into contact with the mold and solidifies during the process of descending to the center position 33 of the static magnetic field forms a slab surface layer having a thickness d. Therefore,
The time required to draw the distance l at the casting speed v is expressed as l/v. On the other hand, since the average solidification rate of the molten metal is f, the solidification shell thickness d of the surface layer of the slab at the center position 33 of the static magnetic field zone is expressed as d=f×(l/v), and from this equation, the above (1) ) formula is obtained. At a position a distance l below the mold level set in this way, over the entire width of the slab,
Direct current magnetic flux is applied across the thickness of the slab with a certain width in the casting direction to form a static magnetic field of a predetermined strength, and the flow in the molten metal pool caused by injection is controlled by the part of this static magnetic field. By braking, mixing of the upper and lower layers at the position where the upper and lower layers contact can be suppressed to a minimum. At that time, the stronger the strength of the magnetic field is within the range that does not interfere with casting work, the stronger the braking force against the molten metal flow, and the wider the width of the static magnetic field band in the casting direction, the stronger the braking force. In some cases, the width of the band becomes a transition layer between the upper and lower layers, and from this point of view, the width of the static magnetic field band in the casting direction does not necessarily have to be wide. The phenomenon that the flow velocity attenuates when a conductive fluid moves in a static magnetic field is a long-known fact known as electromagnetic braking, but the present invention sets the position where this braking force works at a certain position in the casting direction. The target is a manufacturing process in which a composite metal material is obtained by supplying molten metals of different compositions to the upper and lower parts of the molten metal, and the thickness of the surface layer is controlled by setting the above-mentioned positions. Electromagnets may be used to generate this static magnetic field, and permanent magnets may also be used. In addition, controlling the amount of injection from each nozzle to match the amount of coagulation in the upper and lower portions is essential in order to suppress mixing as well as the effect of the static magnetic field. In other words, if the injection amount ratio of both types of molten metal changes while suppressing the mixing of both layers by a static magnetic field, even the fluctuation within the static magnetic field will cause mixing at the boundary to some extent. Furthermore, if the boundary shifts outside the static magnetic field zone, suppression of mixing can no longer be expected. Further, this variation in the injection amount ratio itself promotes mixing. Therefore, it is necessary to take some measure against these mixing factors by providing a static magnetic field band having a certain width in the casting direction. It is preferable to provide this width of 20 cm or more (that is, ±10 cm or more of the center position) if possible. If the width is narrower than 20 cm, there is a high possibility that the boundary will shift outside the static magnetic field band when the injection rate ratio changes. Furthermore, as shown in FIG. 6, for example, the present inventors added a predetermined alloying element to either the upper pool or the lower pool by supplying it with a wire, thereby increasing the alloy composition of the molten metal in that pool. It was confirmed that it was possible to obtain the desired composite metal material consisting of surface layer components and inner layer components by controlling the concentration and casting while suppressing mixing of the upper and lower pools using a static magnetic field zone. In addition, when adding alloying elements to the lower pool using a wire, since the wire is inserted from the surface of the hot water, there is a possibility that it will be dissolved in the upper pool. Therefore, in order to prevent the conowire from dissolving, it is effective to use a coated wire that is designed not to dissolve in the upper pool but to dissolve in the lower pool. An example of this situation is shown in FIG.
In this case, the coated wire 35 is connected to the lower pool 3.
4, and the wire 35 can be dissolved here to obtain a predetermined concentration. When the wire is supplied to the upper pool, it is not necessary to use a coated wire. (Example) Two types of molten steel, 18-8 stainless steel and general medium carbon steel, as shown in Table 1, are held in separate tundishes, and the upper part is heated using separate immersion nozzles.
was injected into the lower part.
【表】
鋳型形状は250mm（厚）×1000mm（幅）、鋳造速
度は1m／minとした。この連鋳機における鋳造
速度は1m／minの場合のシエルの凝固速度ｆは
次式で与えられる。
表層18−８ステンレス鋼、内層が一般中炭鋼を
製造するに際して表層厚を20mmに設定するため
に、(1)式および(2)式よりｌ＝1mの位置を中心と
して鋳造方向の帯が±10cmの鋳片幅方向に均一な
静磁場を与えた。磁速密度は5000ガウスであつ
た。上層に注入するステンレス溶鋼用の浸漬ノズ
ルの吐出孔は湯面レベルの約100mm下の静磁場帯
の下端を出たところ、一方下層に注入する中炭溶
鋼用の浸漬ノズルの吐出孔は静磁場帯の直下とし
た。初めの鋳造長10mの間直流静磁場を発生さ
せ、その後静磁場無しで鋳造した。鋳造後各々の
定常状態の代表的個所から鋳片サンプルを切り出
し、その断面について調査した。
第４図(a)静磁場を形成させたサンプル、(b)形成
しなかつたサンプルの鋳片表面からのCrの濃度
分布を示した。サンプル(a)では表面から20mmの層
がステンレス鋼の成分になつており、また、その
内側の層の組成である一般中炭鋼の成分への遷移
層の厚みが極めてうすいのに対し、サンプル(b)で
はCr濃度が表面では高いもののすぐ内側で急に
低下しており、プール内で混合が生じた事を示し
ている。
（発明の効果）
以上述べたように、本発明によれば、２層間の
混合を最低限におさえ、表層と内層との境界の明
瞭な複合金属材を得ることが可能となる。[Table] The mold shape was 250 mm (thickness) x 1000 mm (width), and the casting speed was 1 m/min. When the casting speed in this continuous casting machine is 1 m/min, the solidification speed f of the shell is given by the following equation. When manufacturing the surface layer of 18-8 stainless steel and the inner layer of general medium carbon steel, in order to set the surface layer thickness to 20 mm, from equations (1) and (2), a band in the casting direction centered at the position l = 1 m is calculated. A uniform static magnetic field of ±10 cm was applied in the slab width direction. The magnetic velocity density was 5000 Gauss. The discharge hole of the immersed nozzle for molten stainless steel injected into the upper layer exits the lower end of the static magnetic field approximately 100 mm below the melt level, while the discharge hole of the immersed nozzle for medium-coal molten steel injected into the lower layer exits the static magnetic field. It was placed directly below the obi. A DC static magnetic field was generated during the initial casting length of 10 m, and then casting was performed without a static magnetic field. After casting, slab samples were cut from representative locations in each steady state, and their cross sections were investigated. Figure 4 shows the Cr concentration distribution from the slab surface of (a) a sample in which a static magnetic field was formed and (b) a sample in which no static magnetic field was formed. In sample (a), the layer 20 mm from the surface has the composition of stainless steel, and the thickness of the transition layer to the composition of ordinary medium-coal steel, which is the inner layer, is extremely thin. In (b), the Cr concentration is high at the surface but suddenly drops just inside, indicating that mixing has occurred within the pool. (Effects of the Invention) As described above, according to the present invention, it is possible to minimize mixing between two layers and obtain a composite metal material with a clear boundary between the surface layer and the inner layer.
第１図ａ，ｂは本発明を実施するための装置の
一例を示す図、第２図は鋳型内で組成の異なる金
属の混合を抑えるために耐火物製の隔壁２７を設
けた従来の方法を示す図、第３図は２本の浸漬ノ
ズル１２，１３で鋳型内溶融金属プール１４の鋳
造方向の単なる位置に異なる組成の溶融金属を注
入する従来の方法を示す図、第４図は鋳片表層部
のCr濃度分布を示す図、第５図ａ，ｂは、本発
明における(1)式を説明するための図で、ａは本発
明の実施状況を示す図、ｂは静磁場帯の中心位置
３３における鋳片断面図、また、第６図は下部プ
ール３４に被覆ワイヤー３５による合金添加を実
施しているときの図である。
１，１１，２１……鋳型、２，３，１２，１
３，２２，２３……浸漬ノズル、４，１４，２４
……鋳型内溶融金属プール、５，１５，２５……
複合金属材の表層部、６，１６，２６……複合金
属材の内層凝固部、８……磁石、９……複合金属
材、１０……磁力線、２７……耐火物製隔壁、３
０……上部プール、３１……溶湯湯面、３２……
静磁場帯、３３……静磁場帯の中心位置、３４…
…下部プール、３５……被覆ワイヤー、Ａ……鋳
造方向。
Figures 1a and b are diagrams showing an example of an apparatus for carrying out the present invention, and Figure 2 is a conventional method in which a partition wall 27 made of refractory material is provided to suppress mixing of metals with different compositions in the mold. FIG. 3 is a diagram showing a conventional method of injecting molten metal of different composition into a mere position in the casting direction of a molten metal pool 14 in a mold using two immersion nozzles 12 and 13, and FIG. Figures 5a and 5b are diagrams showing the Cr concentration distribution in one surface layer, and are diagrams for explaining equation (1) in the present invention; a is a diagram showing the implementation status of the present invention; FIG. 6 is a cross-sectional view of the cast slab at the center position 33 of FIG. 1, 11, 21...Mold, 2, 3, 12, 1
3, 22, 23...Immersion nozzle, 4, 14, 24
... Molten metal pool in the mold, 5, 15, 25...
Surface layer part of composite metal material, 6, 16, 26... Inner layer solidified part of composite metal material, 8... Magnet, 9... Composite metal material, 10... Line of magnetic force, 27... Partition wall made of refractory material, 3
0... Upper pool, 31... Molten metal surface, 32...
Static magnetic field belt, 33...Center position of static magnetic field band, 34...
...Lower pool, 35...Coated wire, A...Casting direction.
Claims (1)
離ｌだけ下方の位置を中心とし、かつその上下に
一定の幅を有する領域において、鋳片の厚みを横
切る方向の直流磁束を鋳片全幅に亙つて付与する
とともに、該直流磁束によつて形成される静磁場
帯を境界としてその上下に組成の異なる金属を供
給することを特徴とする複合金属材の連続鋳造方
法。 ｌ＝dv／ｆ ……(1) ここで、ｌ：鋳型内湯面レベルからの距離 ｄ：複合金属鋳片の表層厚み ｖ：鋳片の引抜速度 ｆ：鋳片の平均凝固速度 ２ 上下いずれかの金属成分を、供給する金属ワ
イヤーによつて調整する特許請求の範囲第１項記
載の複合金属材の連続鋳造方法。 ３ 前記一定の幅が少なくとも10cmである特許請
求の範囲第１項記載の複合金属材の連続鋳造方
法。[Claims] 1. In a region centered at a position below the mold level by a distance l determined by equation (1) and having a constant width above and below, A continuous casting method for a composite metal material, characterized in that DC magnetic flux is applied over the entire width of the slab, and metals having different compositions are supplied above and below the static magnetic field zone formed by the DC magnetic flux as a boundary. . l=dv/f...(1) where, l: Distance from the mold surface level d: Surface layer thickness of the composite metal slab v: Drawing speed of the slab f: Average solidification rate of the slab 2 Upper or lower 2. The continuous casting method for a composite metal material according to claim 1, wherein the metal components are adjusted by the supplied metal wire. 3. The method of continuous casting of a composite metal material according to claim 1, wherein the certain width is at least 10 cm.
Priority Applications (5)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25289886A JPS63108947A (en) | 1986-10-24 | 1986-10-24 | Continuous casting method for complex steel |
| US07/107,471 US4828015A (en) | 1986-10-24 | 1987-10-09 | Continuous casting process for composite metal material |
| CA000549701A CA1296864C (en) | 1986-10-24 | 1987-10-20 | Continuous casting process for composite metal material |
| EP87309281A EP0265235B1 (en) | 1986-10-24 | 1987-10-21 | Continuous casting of composite metal material |
| DE8787309281T DE3767278D1 (en) | 1986-10-24 | 1987-10-21 | CONTINUOUS CASTING OF COMPOSITE METAL. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25289886A JPS63108947A (en) | 1986-10-24 | 1986-10-24 | Continuous casting method for complex steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63108947A JPS63108947A (en) | 1988-05-13 |
| JPH0320295B2 true JPH0320295B2 (en) | 1991-03-19 |
Family
ID=17243704
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25289886A Granted JPS63108947A (en) | 1986-10-24 | 1986-10-24 | Continuous casting method for complex steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63108947A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992018271A1 (en) * | 1991-04-12 | 1992-10-29 | Nippon Steel Corporation | Method of continuous casting of multi-layer slab |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0366447A (en) * | 1989-08-04 | 1991-03-22 | Nippon Steel Corp | Method for casting layered cast slab |
| JPH03229819A (en) * | 1990-02-02 | 1991-10-11 | Nippon Steel Corp | Production of clad steel plate excellent in corrosion resistance |
| JPH03243245A (en) * | 1990-02-20 | 1991-10-30 | Nippon Steel Corp | Production of combined steel plate with continuous casting |
| JPH03285016A (en) * | 1990-04-02 | 1991-12-16 | Nippon Steel Corp | Manufacture of clad steel having superior corrosion resistance and toughness |
| JPH0569088A (en) * | 1991-04-18 | 1993-03-23 | Nippon Steel Corp | Method for continuously casting complex metal material |
| JPH05185185A (en) * | 1992-01-13 | 1993-07-27 | Nippon Steel Corp | Clad steel cast slab using scrap as raw material |
| EP0619179A1 (en) * | 1993-04-06 | 1994-10-12 | Nippon Steel Corporation | Wear resisting steel for welded pipes, and manufacturing process |
| JPH0760408A (en) * | 1993-08-24 | 1995-03-07 | Nippon Steel Corp | Production of steel plate for thin sheet |
| KR100188551B1 (en) * | 1993-11-22 | 1999-06-01 | 아사무라 다까시 | Continuously cast slab of extremely low carbon steel and thin extremely low carbon steel sheet in which surface defect rerely occurs during steel sheet manufacturing step and method of manufacturing the same slab and steel sheet |
| JP6123549B2 (en) * | 2013-07-30 | 2017-05-10 | 新日鐵住金株式会社 | Manufacturing method of continuous cast slab |
| JP6631162B2 (en) | 2015-10-30 | 2020-01-15 | 日本製鉄株式会社 | Continuous casting method and continuous casting apparatus for multilayer slab |
| TW202015829A (en) | 2018-06-08 | 2020-05-01 | 日商日本製鐵股份有限公司 | Method, device, and program for controlling continuous casting process for multi layered slab |
| KR102227826B1 (en) * | 2018-10-26 | 2021-03-15 | 주식회사 포스코 | Casting equipment and casting method |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6138751A (en) * | 1984-07-31 | 1986-02-24 | Ishikawajima Harima Heavy Ind Co Ltd | Method for dissipating wave of pouring basin in continuous casting machine |
| JPS61129261A (en) * | 1984-11-28 | 1986-06-17 | Nippon Steel Corp | Production of continuously cast steel ingot having less surface defect |
-
1986
- 1986-10-24 JP JP25289886A patent/JPS63108947A/en active Granted
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1992018271A1 (en) * | 1991-04-12 | 1992-10-29 | Nippon Steel Corporation | Method of continuous casting of multi-layer slab |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63108947A (en) | 1988-05-13 |
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