JPH09239519A - Manufacture of electroslag re-melted cast billet, and manufacture of turbine rotor shaft by electroslag re-melting - Google Patents
Manufacture of electroslag re-melted cast billet, and manufacture of turbine rotor shaft by electroslag re-meltingInfo
- Publication number
- JPH09239519A JPH09239519A JP8079285A JP7928596A JPH09239519A JP H09239519 A JPH09239519 A JP H09239519A JP 8079285 A JP8079285 A JP 8079285A JP 7928596 A JP7928596 A JP 7928596A JP H09239519 A JPH09239519 A JP H09239519A
- Authority
- JP
- Japan
- Prior art keywords
- amount
- molten slag
- slag
- specific component
- electroslag
- 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
Landscapes
- Turbine Rotor Nozzle Sealing (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、成分分布に傾斜を
持たせたタービンロータシャフトなどを良好に、かつ効
率よく製造することができるエレクトロスラグ再溶解
（以下「ＥＳＲ」という）鋳塊の製造方法およびＥＳＲ
によるタービンロータシャフトの製造方法に関するもの
である。TECHNICAL FIELD The present invention relates to the production of an electroslag remelting (hereinafter referred to as “ESR”) ingot capable of favorably and efficiently producing a turbine rotor shaft or the like having an inclined component distribution. Method and ESR
The present invention relates to a method for manufacturing a turbine rotor shaft according to.
【０００２】[0002]
【従来の技術】発電機等に用いられるタービンロータシ
ャフトは、高温の蒸気に晒されるため高温特性に優れて
いる必要があり、このような観点からシャフト材料には
高温強度に優れた高Ｃｒ（例えば５〜１３ｗｔ％Ｃｒ）
系鋼が広く使われている。しかし、高Ｃｒ鋼は耐焼付性
の点では劣っており、ロータシャフトの軸部において焼
付けを起こしやすいという問題がある。このため高Ｃｒ
系タービンロータシャフトでは軸部表面に耐焼付け性に
優れた低Ｃｒ系の材料を肉盛り溶接して、軸部の耐焼付
け性を改善する方法が提案、実施されている。2. Description of the Related Art Turbine rotor shafts used in generators and the like are exposed to high temperature steam and therefore must have excellent high temperature characteristics. (For example, 5 to 13 wt% Cr)
Steels are widely used. However, high Cr steel is inferior in seizure resistance, and there is a problem that seizure is likely to occur in the shaft portion of the rotor shaft. Therefore, high Cr
In a turbine type turbine rotor shaft, a method has been proposed and practiced to improve the seizure resistance of the shaft portion by depositing a low Cr material having excellent seizure resistance on the surface of the shaft portion by overlay welding.
【０００３】ところで、最近では発電効率をさらに向上
させる等の観点から、タービンロータシャフトの高温特
性に対する要求は益々厳しいものになっており、上記高
Ｃｒ系シャフトにおいても、さらに高温特性（特に高温
強度）を改善する目的で該鋼にＢを添加することが提案
されている。しかし、合金元素として添加されるＢは鋼
の高温強度を著しく改善するものの、一方で溶接性を著
しく損なうという性質を有しており、上記した肉盛り溶
接において割れ等を生じさせるという問題があり、ター
ビンロータシャフトへのＢ含有の障害になっている。こ
のような問題は、溶接性が重視されるタービンロータシ
ャフトの軸部でＢ量を少なくし、高温特性が重要視され
るタービンロータシャフトの胴部で多くのＢを含有させ
ることによって解決することができる。By the way, recently, from the viewpoint of further improving the power generation efficiency, the demand for high temperature characteristics of the turbine rotor shaft has become more and more strict, and even in the above high Cr type shaft, further high temperature characteristics (particularly high temperature strength) are obtained. It has been proposed to add B to the steel for the purpose of improving However, B added as an alloying element remarkably improves the high temperature strength of steel, but has the property of significantly impairing the weldability, and there is a problem that cracks and the like occur in the above-mentioned build-up welding. , B is an obstacle to the turbine rotor shaft. Such a problem should be solved by reducing the amount of B in the shaft portion of the turbine rotor shaft where weldability is important and containing a large amount of B in the body portion of the turbine rotor shaft where high temperature characteristics are important. You can
【０００４】ところで、タービンロータシャフト（特に
大型タービンロータシャフト）の製造では、偏析の発生
防止等の点で有利なエレクトロスラグ再溶解（以下「Ｅ
ＳＲ」という）法が広く採用されており、上記のように
成分分布に傾斜を持たせた一体素材をＥＳＲによって製
造する際には、組成（Ｂ量）の異なる電極を用意し、こ
れらの電極を軸方向に連結して両方の電極を連続的に再
溶解することによって成分調整を行う方法が提案されて
いる（例えば、特公昭５６−２３３６７号、同５６−１
４８４２号等）。In the manufacture of turbine rotor shafts (especially large turbine rotor shafts), electroslag remelting (hereinafter referred to as "E") is advantageous in terms of preventing segregation.
The SR method) is widely adopted, and when an integrated material having a gradient in the component distribution as described above is manufactured by ESR, electrodes having different compositions (B amount) are prepared, and these electrodes are prepared. Has been proposed in which the components are adjusted by axially connecting and remelting both electrodes continuously (for example, Japanese Patent Publication Nos. 56-23367 and 56-1).
4842).
【０００５】[0005]
【発明が解決しようとする課題】しかし、成分分布に傾
斜を有する一体素材を上記した従来の方法によって製造
すると、異成分の電極の製造や電極同士の連結に手間が
かかり製造効率が悪い上に、成分の異なる電極の連結部
分に対応してＥＳＲ鋳塊に不連続部が形成されたり、連
結部分が溶解する際に溶解速度等が不安定になって不良
な鋳塊組織が形成されたりして、良好なＥＳＲ鋳塊を効
率よく製造することができないという問題がある。However, when the monolithic material having a gradient in the component distribution is manufactured by the above-mentioned conventional method, it is troublesome to manufacture electrodes of different components and to connect the electrodes, and the manufacturing efficiency is poor. , A discontinuous portion may be formed in the ESR ingot corresponding to the connecting portion of electrodes having different components, or the melting rate may become unstable when the connecting portion is melted, and a defective ingot structure may be formed. Therefore, there is a problem that a good ESR ingot cannot be efficiently manufactured.
【０００６】本発明は、上記事情を背景としてなされた
ものであり、成分分布に傾斜のあるタービンロータシャ
フト等のＥＳＲ鋳塊を不連続部等を形成することなく良
好に、かつ効率よく製造することができるＥＳＲ鋳塊の
製造方法およびＥＳＲによるタービンロータシャフトの
製造方法を提供することを目的とする。The present invention has been made in view of the above circumstances, and it is possible to efficiently and efficiently manufacture an ESR ingot such as a turbine rotor shaft having an inclined component distribution without forming discontinuous portions or the like. An object of the present invention is to provide a method for manufacturing an ESR ingot and a method for manufacturing a turbine rotor shaft by ESR that can be performed.
【０００７】[0007]
【課題を解決するための手段】上記課題を解決するため
本発明のうち第１の発明のＥＳＲ鋳塊の製造方法は、特
定成分の含有量分布に傾斜をもたせたＥＳＲ鋳塊の製造
方法において、特定成分を含有する電極を使用して、Ｅ
ＳＲ中に適宜、該特定成分に関する溶融金属と溶融スラ
グ間の化学反応が平衡状態から外れるように該特定成分
化合物の含有量が上記平衡状態を保つ量と異なる溶融ス
ラグを使用して、溶融金属と溶融スラグ間の成分の移動
の変化を利用してＥＳＲ鋳塊の位置によって特定成分の
含有量を変化させることを特徴とする。In order to solve the above problems, the method for producing an ESR ingot according to the first aspect of the present invention is a method for producing an ESR ingot in which the content distribution of a specific component is inclined. , Using electrodes containing specific components, E
The molten metal is appropriately used in SR by using a molten slag having a content of the compound of the specific component different from the amount for maintaining the equilibrium state so that the chemical reaction between the molten metal and the molten slag relating to the specific component deviates from the equilibrium state. It is characterized in that the content of the specific component is changed depending on the position of the ESR ingot by utilizing the change in the movement of the component between the molten slag and the molten slag.
【０００８】また、第２の発明のＥＳＲ鋳塊の製造方法
は、第１の発明において、ＥＳＲ中に、特定成分化合物
の含有量が溶融スラグと異なる追加スラグを溶融スラグ
中に投入して溶融金属と溶融スラグ間における特定成分
の移動を変化させることを特徴とする。The method for producing an ESR ingot according to the second aspect of the invention is the method of producing the ESR ingot according to the first aspect, wherein an additional slag having a specific component compound content different from that of the molten slag is added to the molten slag and melted. It is characterized by changing the movement of a specific component between the metal and the molten slag.
【０００９】第３の発明のＥＳＲ法によるタービンロー
タシャフトの製造方法は、軸部のＢ含有量を胴部よりも
低くしたタービンロータシャフトをＥＳＲによって製造
する方法において、胴部Ｂ量に対応した量のＢを含有す
るＥＳＲ用電極を使用して、軸部に対応する電極の再溶
解時に反応に関わるＢと平衡する量よりもＢ酸化物量が
少ない溶融スラグを使用するとともに、胴部に対応する
電極の再溶解時に反応に関わるＢと平衡する量とほぼ同
量以上のＢ酸化物を含有する溶融スラグを使用すること
を特徴とする。The method of manufacturing a turbine rotor shaft by the ESR method of the third invention corresponds to the amount of the body portion B in the method of manufacturing the turbine rotor shaft in which the B content of the shaft portion is lower than that of the body portion by ESR. Using the ESR electrode containing a large amount of B, use molten slag that has a smaller amount of B oxide than the amount that equilibrates with B involved in the reaction when the electrode corresponding to the shaft portion is redissolved, and is compatible with the body It is characterized in that a molten slag containing substantially the same amount or more of B oxide as the amount equilibrating with B involved in the reaction at the time of remelting the electrode is used.
【００１０】第４の発明のＥＳＲ法によるタービンロー
タシャフトの製造方法は、第３の発明において、軸部が
両端にあるタービンロータシャフトをＥＳＲによって製
造する際に、一端の軸部に対応する電極を再溶解する再
溶解初期にＢ酸化物を含まないスラグを使用し、他端の
軸部に対応する電極の再溶解時に、Ｂ酸化物を含まない
追加スラグを溶融スラグに投入することを特徴とする。In the turbine rotor shaft manufacturing method by the ESR method of the fourth invention, in the third invention, when the turbine rotor shaft having the shaft portions at both ends is manufactured by the ESR, an electrode corresponding to the shaft portion at one end is provided. A slag that does not contain B oxide is used in the initial stage of remelting, and an additional slag that does not contain B oxide is added to the molten slag when the electrode corresponding to the shaft portion at the other end is redissolved. And
【００１１】[0011]
【作用】通常のＥＳＲ鋳塊の製造方法によれば、特定成
分を適当量含有する電極と特定成分化合物を適当量含む
スラグを用いてＥＳＲを行うと、溶融金属中の特定成分
と溶融スラグ中の特定成分化合物が平衡状態になり、特
定成分を均一に含有したＥＳＲ鋳塊を製造することがで
きる。According to the usual method for producing an ESR ingot, when ESR is performed using an electrode containing an appropriate amount of a specific component and a slag containing an appropriate amount of a compound of a specific component, the specific component in the molten metal and the molten slag It becomes possible to produce an ESR ingot in which the compound of the specific component is brought into an equilibrium state and the specific component is uniformly contained.
【００１２】しかし、本発明に従って、上記平衡状態を
保つ量と異なる量の特定成分化合物を含有する溶融スラ
グを使用すると、溶融金属と溶融スラグとの間で特定成
分の移動に変化が生じる。例えば、溶融スラグ中の特定
成分化合物の量が平衡状態を保つ量よりも少ないと、溶
融金属中の特定成分が溶融スラグ中に移動して特定成分
化合物を生成し、遂には平衡状態に至る。これにより、
ＥＳＲ鋳塊中の特定成分の含有量を部分的に減少させる
ことができる。また、これと逆に溶融スラグ中の特定成
分化合物の量が平衡状態を保つ量よりも多いと、上記反
応の進行は停止し、反応系によっては溶融スラグ中の特
定成分化合物が分解して該特定成分が溶融金属中に移動
してＥＳＲ鋳塊中の特定成分の含有量を増加させる。However, according to the present invention, when the molten slag containing the specific component compound in an amount different from the above-mentioned equilibrium state is used, a change occurs in the movement of the specific component between the molten metal and the molten slag. For example, when the amount of the specific component compound in the molten slag is less than the amount that maintains the equilibrium state, the specific component in the molten metal moves into the molten slag to form the specific component compound, and finally the equilibrium state is reached. This allows
It is possible to partially reduce the content of the specific component in the ESR ingot. On the contrary, when the amount of the specific component compound in the molten slag is larger than the amount which maintains the equilibrium state, the progress of the reaction is stopped, and the specific component compound in the molten slag is decomposed and decomposed depending on the reaction system. The specific component moves into the molten metal to increase the content of the specific component in the ESR ingot.
【００１３】但し、溶融金属の特定成分と、溶融スラグ
の特定成分化合物との化学反応では、通常は、特定成分
化合物が生成される方向が反応の自発方向になるので、
電極には、鋳塊の通常部分の特定成分量に見合う特定成
分を含有させておき、特定成分量を少なくしたい鋳塊部
分に対応する再溶解時に、特定成分化合物の量が少ない
スラグを使用するのが望ましい。この方法によれば、自
発反応を利用して、鋳塊の特定成分量を容易に制御する
ことができる。上記した特定成分化合物の量が少ないス
ラグは、ＥＳＲ初期からこのようなスラグを使用する他
に、特定成分化合物量が少ないか、全く含有しない追加
スラグを投入することによって得られる。また、このよ
うな反応系では、溶融スラグの特定成分化合物の量が少
ないときに、該化合物量が多い追加スラグを投入すれ
ば、鋳塊中のＢ量の減少を早期に停止させて、平衡状態
に移行させることができる。However, in the chemical reaction between the specific component of the molten metal and the specific component compound of the molten slag, usually, the direction in which the specific component compound is produced is the spontaneous direction of the reaction,
The electrode contains a specific component commensurate with the specific component amount of the normal portion of the ingot, and when remelting corresponding to the ingot portion where the specific component amount is desired to be reduced, use slag with a small amount of the specific component compound Is desirable. According to this method, the amount of the specific component of the ingot can be easily controlled by utilizing the spontaneous reaction. The above-mentioned slag with a small amount of the specific component compound is obtained by using such a slag from the early stage of ESR, and by adding an additional slag with a small amount of the specific component compound or no slag. Further, in such a reaction system, when the amount of the specific component compound of the molten slag is small, if the additional slag having a large amount of the compound is added, the decrease in the amount of B in the ingot is stopped early and the equilibrium is reached. Can be moved to a state.
【００１４】なお、上記操業では電極には鋳塊の通常部
分に見合う（対応する）量の特定成分を含有させるが、
その成分の種別や操業条件等によっては、電極溶解時の
成分蒸発等によって歩留まりが変わり、反応に関わる成
分の量が異なってくる。したがって、電極中にはこの歩
留まりを想定した量の特定成分を含有させる必要があ
る。また、特定成分化合物と平衡するＢ量としては、上
記した反応に関わる成分の量が対象になる。In the above operation, the electrode contains a specific component in an amount corresponding (corresponding) to the normal portion of the ingot,
Depending on the type of the components, operating conditions, etc., the yield may change due to component evaporation or the like when the electrodes are dissolved, and the amount of the components involved in the reaction may differ. Therefore, it is necessary to include the specific component in the electrode in an amount that assumes this yield. Further, the amount of B that is in equilibrium with the specific component compound is the amount of the components involved in the above reaction.
【００１５】上記の各作用は、ＥＳＲ鋳塊としてタービ
ンロータシャフトを製造する際にも得られる。特定成分
としてＢを含有するタービンロータシャフトを製造する
場合には、電極中から溶解したＢと溶融スラグ中のＢ酸
化物とが下記反応等によって平衡状態になる。なお、Ｂ
は比較的蒸発しやすい元素であり、ＥＳＲ中にも一部が
蒸発して、数十％程度の歩留まりで下記反応に関わるこ
とになる。 ４Ｂ＋３Ｏ2＝２Ｂ2Ｏ3 ３ＳｉＯ2＋４Ｂ＝３Ｓｉ＋２
Ｂ2Ｏ3 ここで、Ｂ含有量が少ない軸部に対応する電極の再溶解
時に、Ｂ酸化物量が平衡状態よりも少ない（含有しない
場合を含む）溶融スラグを使用すると、上記反応は平衡
状態にないため右方向に進行し、溶融金属中のＢが溶融
スラグ中に移動し、その結果、鋳塊中のＢ量が減少す
る。上記反応が進行すると、溶融スラグ中のＢ酸化物量
が次第に増えるので、上記反応は平衡状態になり、溶鋼
中のＢ量はほぼ一定になる。なお、この状態でも溶鋼中
からはＢの蒸発があるため、溶鋼中のＢ量は電極中のＢ
量の数十％になっており、鋳塊のＢ量は、電極のＢ量に
対応したものになる。したがって、これら反応の変化を
利用して、軸部のみでＢ含有量を減少させることができ
る。上記したＢ酸化物量が少ない溶融スラグは、ＥＳＲ
初期からこのようなスラグを使用することによって得る
ことができ、また、Ｂ酸化物量が少ない追加スラグを溶
融スラグ中に投入することによって得ることもできる。Each of the above-mentioned actions is also obtained when manufacturing a turbine rotor shaft as an ESR ingot. When manufacturing a turbine rotor shaft containing B as a specific component, B dissolved in the electrode and B oxide in the molten slag are in an equilibrium state by the following reaction. Note that B
Is an element that evaporates relatively easily, and part of it evaporates during ESR, and is involved in the following reaction with a yield of about several tens of percent. 4B + 3O 2 = 2B 2 O 3 3SiO 2 + 4B = 3Si + 2
B 2 O 3 Here, when remelting the electrode corresponding to the shaft portion having a low B content, when the molten slag having a B oxide content smaller than that in the equilibrium state (including the case where it does not contain B oxide) is used, the above reaction is in an equilibrium state. Therefore, B in the molten metal moves into the molten slag, and as a result, the amount of B in the ingot decreases. As the above reaction progresses, the amount of B oxide in the molten slag gradually increases, so that the above reaction is in equilibrium and the amount of B in the molten steel becomes almost constant. Even in this state, there is evaporation of B from the molten steel, so the amount of B in the molten steel is the B in the electrode.
It is several tens% of the amount, and the B content of the ingot corresponds to the B content of the electrode. Therefore, the B content can be reduced only in the shaft portion by utilizing these changes in the reaction. The above-mentioned molten slag with a small amount of B oxide is ESR
It can be obtained by using such a slag from the beginning, or by adding an additional slag having a small amount of B oxide into the molten slag.
【００１６】一方、胴部に対応する電極の再溶解時に
は、反応に関わるＢと平衡する量とほぼ同量以上のＢ酸
化物を含有する溶融スラグを使用することにより、電極
に含有させたＢ量によって意図（歩留まりを含めて）さ
れたＢ量が鋳塊中に含まれることになる。上記したＢ酸
化物量がほぼ平衡状態にある溶融スラグは、上記した反
応の進行によって平衡状態になることにより得ることが
できるものであり、また、Ｂ酸化物量が少ない溶融スラ
グ中にＢ酸化物量が多い追加スラグを投入することによ
って得ることもできる。なお、追加スラグの投入は後述
するように複数回繰り返すことも可能である。なお、鋳
塊のＢ量の減少は、平衡状態を超える量のＢ酸化物を含
む溶融スラグの使用によっても停止される。On the other hand, when the electrode corresponding to the body is redissolved, B contained in the electrode is prepared by using a molten slag containing B oxide in an amount equal to or more than the equilibrium amount of B involved in the reaction. The amount of B intended by the amount (including the yield) is included in the ingot. The above-mentioned molten slag in which the amount of B oxide is almost in equilibrium can be obtained by the above-mentioned reaction progressing into an equilibrium state, and the amount of B oxide in the molten slag having a small amount of B oxide is It can also be obtained by adding a large amount of additional slag. The addition of additional slag can be repeated a plurality of times as described later. The reduction of the B content of the ingot is also stopped by using the molten slag containing the B oxide in an amount exceeding the equilibrium state.
【００１７】また、タービンロータシャフトの両端に軸
部を有する場合には、ＥＳＲ初期にＢ酸化物を含まない
スラグを用いることにより、ＥＳＲ初期にＢが酸化され
てスラグ中に移動し、鋳塊端部でＢ含有量が低下し、次
第にスラグ中のＢ酸化物が増加するにしたがって、鋳塊
中のＢ含有量も増加する。したがって鋳塊の一端部に位
置する軸部でＢ含有量が少なくなり、鋳塊胴部から他端
部側に至るまでは、電極のＢ含有量に従ってほぼ一定の
Ｂ含有量になる。さらに、鋳塊の他端部ではＢ含有量を
含まない追加スラグを投入することによりＥＳＲ初期と
同様にして鋳塊中のＢ量が減少し、鋳塊の他端部、すな
わち軸部でＢ量を減少させることができる。なお、ＥＳ
Ｒ初期やＢ酸化物含有量の少ない（含有しない場合を含
む）追加スラグを投入した後にも、溶融スラグ中のＢ酸
化物量は次第に増大するので、さらに追加スラグを１回
以上投入することができる。この追加スラグの再投入に
よりＢ含有量の少ない部分を所望の範囲に容易に調整す
ることができる。Further, when the turbine rotor shaft has shaft portions at both ends, by using slag containing no B oxide in the early stage of ESR, B is oxidized in the early stage of ESR and moves into the slag, and The B content in the ingot also increases as the B content in the end portion decreases and the B oxide in the slag gradually increases. Therefore, the B content is reduced in the shaft portion located at one end of the ingot, and the B content is almost constant according to the B content of the electrode from the ingot body portion to the other end side. Further, by adding an additional slag containing no B content to the other end of the ingot, the amount of B in the ingot is reduced in the same manner as in the initial stage of ESR, and the other end of the ingot, that is, the shaft portion, has a B content. The amount can be reduced. In addition, ES
The amount of B oxide in the molten slag gradually increases even after the initial R and after the addition of the additional slag having a small B oxide content (including the case where it is not included), the additional slag can be further added once or more. . By reintroducing the additional slag, the portion having a small B content can be easily adjusted to a desired range.
【００１８】上記製造過程を経ることによって得られた
タービンロータシャフトは、軸部のＢ量が胴部よりも少
なく、したがってＢを多く含む胴部においてさらに高温
特性が改善されているとともに、軸部の溶接性が良好に
保たれており、焼付け防止のための肉盛り溶接を良好に
行うことができる。このタービンロータシャフトでは、
上記効果を得るために、軸部のＢ量が０〜０．００７％
であるのが望ましく、胴部で０．００８〜０．０３％の
Ｂを含有するのが望ましい。また、上記製造過程を経て
このような成分傾斜を設けるためには、電極としてＢを
０．０２〜０．０８％含有するものを使用するのが望ま
しい。また、軸部、胴部との境界部分では不連続部が存
在することはなく、組織への悪影響も見られず、良好に
濃度分布に傾斜がつけられている。しかも、濃度分布の
傾斜は成分の異なる溶融スラグの使用によって行うこと
ができるので、電極の連結等が不要であり、鋳塊を効率
よく製造することができる。The turbine rotor shaft obtained by the above manufacturing process has a smaller amount of B in the shaft portion than in the body portion, and therefore, the high temperature characteristics are further improved in the body portion containing a large amount of B, and the shaft portion is The weldability of No. 1 is kept good, and the overlay welding for preventing the seizure can be satisfactorily performed. With this turbine rotor shaft,
In order to obtain the above effect, the B content of the shaft portion is 0 to 0.007%
Is desirable, and it is desirable to contain 0.008 to 0.03% of B in the body. Further, in order to provide such a component gradient through the above manufacturing process, it is desirable to use an electrode containing B of 0.02 to 0.08%. In addition, no discontinuity exists at the boundary between the shaft portion and the body portion, no adverse effect on the tissue is observed, and the concentration distribution is favorably inclined. Moreover, since the gradient of the concentration distribution can be obtained by using the molten slag having different components, it is not necessary to connect the electrodes, and the ingot can be efficiently manufactured.
【００１９】[0019]
【発明の実施の形態】本発明で製造するＥＳＲ鋳塊とし
ては、タービンロータシャフトが代表的であるが、これ
に限定されるものではなく、各種用途の材料に適用する
ことができる。ＥＳＲに使用する電極には、上記用途に
合わせて組成を選定し、常法により製造したものを使用
することができる。また、この電極には、所定の目的で
鋳塊に傾斜分布により含有させる特定成分を添加する。
この添加量は、製造するＥＳＲ鋳塊の通常の特定成分量
に合わせるのが望ましい。BEST MODE FOR CARRYING OUT THE INVENTION A turbine rotor shaft is typical as an ESR ingot produced by the present invention, but the present invention is not limited to this, and it can be applied to materials for various applications. As the electrode used for ESR, an electrode manufactured by a usual method with a composition selected according to the above-mentioned application can be used. Further, a specific component to be contained in the ingot by a gradient distribution is added to this electrode for a predetermined purpose.
It is desirable that this addition amount be adjusted to the usual specific component amount of the ESR ingot to be produced.
【００２０】なお、所定の目的で添加される特定成分と
しては種々のものがあるが、例えば、Ｂ、Ｔｉ、Ｚｒを
例示することができる。これら成分は溶融スラグ中では
特定成分化合物として存在するが、通常は酸化物として
存在する。上記した電極は、鋳型の形状、寸法に合わせ
て適切な形状、寸法に製造され、適当な組成のスラグを
用いてＥＳＲされる。ＥＳＲに際しては特別な操業条件
は必要なく、常法により行うことができる。溶融スラグ
には、適宜、平衡状態から外れる量の特定成分化合物を
含むか、全く含まないものが使用される。上記の結果、
溶融金属は鋳型中で凝固し、特定成分が所定の成分量で
傾斜分布しているＥＳＲ鋳塊が得られる。There are various specific components added for a predetermined purpose, and B, Ti and Zr can be exemplified. These components are present as a specific component compound in the molten slag, but are usually present as an oxide. The above-mentioned electrode is manufactured in an appropriate shape and size according to the shape and size of the mold, and ESR is performed using a slag having an appropriate composition. ESR does not require special operating conditions and can be carried out by a conventional method. The molten slag is appropriately used in such a manner that it contains a specific component compound in an amount out of equilibrium or does not contain it at all. As a result of the above,
The molten metal is solidified in the mold to obtain an ESR ingot in which the specific component is distributed in a gradient with a predetermined component amount.
【００２１】[0021]
【実施例】表１に示す組成（特定成分としてＢ含有）を
有するＥＳＲ電極を常法により円柱形状に製造し、下記
の条件でＥＳＲに供した。 ・モールドサイズ：８５０ｍｍ径×３６００ｍｍ高 ・スラグ組成 ：ＣａＦ2−ＣａＯ−Ａｌ2Ｏ3−ＳｉＯ2 ・平均溶解速度 ：６００〜７００ｋｇ／ｈ ・鋼塊サイズ ：８５３ｍｍ径×１９９０ｍｍ長（９１００ｋｇ） ＥＳＲが進み、所定の長さの電極が溶解した時点で表２
に示す条件で繰り返し追加スラグを投入した。得られた
鋳塊の軸方向におけるＢ量分布を測定し、その結果を図
１に示した。図から明らかなように得られた鋳塊は、軸
方向両端部でＢ含有量が少なく（電極Ｂ量の２０〜３０
％程度）、その間で電極のＢ量に見合う量で多くのＢ
（電極Ｂ量の４０〜６０％程度）が安定して含まれてい
た。上記鋳塊を素材として、両端部が軸部、その間が胴
部になるタービンロータシャフトを制作したところ、胴
部では高い高温強度が得られ、一方、軸部では良好な溶
接性が確保されており、耐焼付け性の改善のために低Ｃ
ｒ材で肉盛り溶接を行ったが、良好に溶接することがで
きた。また、上記タービンロータシャフトは、軸部と胴
部との境界部分で不連続部や組織の不良部分は発見され
なかった。Example An ESR electrode having the composition shown in Table 1 (containing B as a specific component) was manufactured into a cylindrical shape by a conventional method, and subjected to ESR under the following conditions. Mold size: 850 mm diameter × 3600 mm high, slag composition: CaF 2 -CaO-Al 2 O 3 -SiO 2 · average dissolving rate: 600~700kg / h · ingot size: 853Mm diameter × 1990Mm length (9100kg) ESR is As shown in Table 2, when the electrode of a predetermined length is dissolved
The additional slag was repeatedly charged under the conditions shown in. The B content distribution in the axial direction of the obtained ingot was measured, and the result is shown in FIG. As is clear from the figure, the ingot obtained has a small B content at both axial end portions (20 to 30% of the electrode B amount).
%), And in the meantime, a large amount of B in the amount commensurate with the amount of B
(About 40 to 60% of the amount of electrode B) was stably contained. Using the above ingot as a raw material, a turbine rotor shaft was manufactured in which both ends were a shaft part and the space between them was a body part, and high temperature strength was obtained in the body part, while good weldability was secured in the shaft part. And low C to improve seizure resistance
The build-up welding was performed with the r material, but the welding was successful. Further, in the turbine rotor shaft, no discontinuity portion or defective structure portion was found at the boundary portion between the shaft portion and the body portion.
【００２２】[0022]
【表１】 [Table 1]
【００２３】[0023]
【表２】 [Table 2]
【００２４】[0024]
【発明の効果】以上説明したように、本発明のエレクト
ロスラグ再溶解鋳塊の製造方法によれば、特定成分の含
有量分布に傾斜をもたせたエレクトロスラグ再溶解鋳塊
の製造方法において、特定成分を含有する電極を使用し
て、エレクトロスラグ再溶解中に適宜、該特定成分に関
する溶融金属と溶融スラグ間の化学反応が平衡状態から
外れるように該特定成分化合物の含有量が上記平衡状態
を保つ量と異なる溶融スラグを使用して、溶融金属と溶
融スラグ間の成分の移動の変化を利用してエレクトロス
ラグ再溶解鋳塊の位置によって特定成分の含有量を変化
させるので、鋳塊に不連続部等形成することなく良好
に、かつ効率よく特定成分の分布量に傾斜を持たせるこ
とができる。As described above, according to the method for producing an electroslag remelting ingot according to the present invention, in the method for producing an electroslag remelting ingot having a gradient in the content distribution of a specific component, Using the electrode containing the component, the content of the specific component compound is adjusted to the above equilibrium state during electroslag remelting so that the chemical reaction between the molten metal and the molten slag relating to the specific component is out of equilibrium. Using different amount of molten slag to keep, the content of a specific component is changed depending on the position of the electro-slag remelting ingot by utilizing the change in the movement of the component between the molten metal and the molten slag, so The distribution amount of the specific component can be satisfactorily and efficiently provided without forming a continuous portion or the like.
【００２５】また、エレクトロスラグ再溶解中に、特定
成分化合物の含有量が溶融スラグと異なる追加スラグを
溶融スラグ中に投入して溶融金属と溶融スラグ間におけ
る特定成分の移動を変化させれば、適切な時期に鋳塊中
の特定成分の含有量を容易に制御することができる。During electroslag remelting, if additional slag having a specific component compound content different from that of the molten slag is added to the molten slag to change the movement of the specific component between the molten metal and the molten slag, The content of the specific component in the ingot can be easily controlled at an appropriate time.
【００２６】また、本発明のエレクトロスラグ再溶解に
よるタービンロータシャフトの製造方法によれば、軸部
のＢ含有量を胴部よりも低くしたタービンロータシャフ
トをエレクトロスラグ再溶解によって製造する方法にお
いて、胴部Ｂ量に対応した量のＢを含有するエレクトロ
スラグ再溶解用電極を使用して、軸部に対応する電極の
再溶解時に反応に関わるＢと平衡する量よりもＢ酸化物
量が少ない溶融スラグを使用するとともに、胴部に対応
する電極の再溶解時に反応に関わるＢと平衡する量とほ
ぼ同量のＢ酸化物を含有する溶融スラグを使用するの
で、軸部のＢ量を減らし、胴部のＢ量を増やしたタービ
ンロータシャフトを不連続部を形成することなく製造す
ることができ、高温特性に優れ、かつ軸部での溶接性に
優れたタービンロータシャフトを得ることができる。Further, according to the method of manufacturing a turbine rotor shaft by electroslag remelting of the present invention, in the method of manufacturing a turbine rotor shaft in which the B content of the shaft portion is lower than that of the body portion by electroslag remelting, Using an electroslag remelting electrode containing an amount of B corresponding to the amount of body B, the amount of B oxide is less than the amount equilibrating with B involved in the reaction when remelting the electrode corresponding to the shaft. In addition to using slag, since the molten slag that contains almost the same amount of B oxide that equilibrates with B involved in the reaction when the electrode corresponding to the body is redissolved is used, the amount of B in the shaft is reduced, A turbine rotor shaft with an increased amount of B in the body can be manufactured without forming discontinuities, and has excellent high-temperature characteristics and excellent weldability at the shaft. It is possible to obtain the shaft.
【００２７】さらに、軸部が両端にあるタービンロータ
シャフトをエレクトロスラグ再溶解によって製造する際
に、一端の軸部に対応する電極を再溶解する再溶解初期
にＢ酸化物を含まないスラグを使用し、他端の軸部に対
応する電極の再溶解時に、Ｂ酸化物を含まない追加スラ
グを溶融スラグに投入すれば、両端軸部で容易にＢ量を
減少させることができ、胴部においても安定してＢを多
く含有させることができる。Furthermore, when a turbine rotor shaft having shafts at both ends is manufactured by electroslag remelting, a slag containing no B oxide is used in the initial stage of remelting for remelting the electrodes corresponding to the shafts at one end. Then, at the time of remelting the electrode corresponding to the shaft portion at the other end, if an additional slag containing no B oxide is added to the molten slag, the amount of B can be easily reduced at both end shaft portions, and Also, a large amount of B can be stably contained.
【図１】 実施例のＥＳＲ鋳塊の軸方向位置におけるＢ
含有量分布を示すグラフである。FIG. 1 shows B at the axial position of the ESR ingot of the embodiment.
It is a graph which shows content distribution.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 山田 人久 北海道室蘭市茶津町４番地 株式会社日本 製鋼所内 (72)発明者 浅野 岩生 北海道室蘭市茶津町４番地 株式会社日本 製鋼所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hitoshi Yamada, No. 4, Chazu-cho, Muroran-shi, Hokkaido, Japan Steel Works, Ltd. (72) Inventor Asano Iwao, No. 4, Chazu-cho, Muroran-shi, Hokkaido, Japan, Japan Steel Works, Ltd.
Claims (4)
エレクトロスラグ再溶解鋳塊の製造方法において、特定
成分を含有する電極を使用して、エレクトロスラグ再溶
解中に適宜、該特定成分に関する溶融金属と溶融スラグ
間の化学反応が平衡状態から外れるように該特定成分化
合物の含有量が上記平衡状態を保つ量と異なる溶融スラ
グを使用して、溶融金属と溶融スラグ間の成分の移動の
変化を利用してエレクトロスラグ再溶解鋳塊の位置によ
って特定成分の含有量を変化させることを特徴とするエ
レクトロスラグ再溶解鋳塊の製造方法1. A method for producing an electroslag remelting ingot having a gradient in the content distribution of a specific component, wherein an electrode containing the specific component is used to appropriately relate the specific component during electroslag remelting. Using a molten slag whose content of the specific component compound is different from the amount which maintains the equilibrium state so that the chemical reaction between the molten metal and the molten slag is out of equilibrium, the transfer of the components between the molten metal and the molten slag is performed. A method for manufacturing an electroslag remelted ingot, characterized in that the content of a specific component is changed by changing the position of the electroslag remelted ingot
化合物の含有量が溶融スラグと異なる追加スラグを溶融
スラグ中に投入して溶融金属と溶融スラグ間における特
定成分の移動を変化させることを特徴とする請求項１記
載のエレクトロスラグ再溶解鋳塊の製造方法2. During electroslag remelting, an additional slag having a specific component compound content different from that of the molten slag is added to the molten slag to change the movement of the specific component between the molten metal and the molten slag. The method for producing an electroslag remelted ingot according to claim 1.
ービンロータシャフトをエレクトロスラグ再溶解によっ
て製造する方法において、胴部Ｂ量に対応した量のＢを
含有するエレクトロスラグ再溶解用電極を使用して、軸
部に対応する電極の再溶解時に反応に関わるＢと平衡す
る量よりもＢ酸化物量が少ない溶融スラグを使用すると
ともに、胴部に対応する電極の再溶解時に反応に関わる
Ｂと平衡する量とほぼ同量以上のＢ酸化物を含有する溶
融スラグを使用することを特徴とするエレクトロスラグ
再溶解によるタービンロータシャフトの製造方法3. A method for manufacturing a turbine rotor shaft having a shaft portion having a B content lower than that of a body portion by electroslag remelting, wherein the electroslag remelting contains B in an amount corresponding to the body portion B amount. Using molten slag that has a smaller amount of B oxide than the amount that equilibrates with B that is involved in the reaction when the electrode corresponding to the shaft portion is redissolved, the reaction is performed when the electrode corresponding to the body portion is redissolved. Method for manufacturing turbine rotor shaft by electro-slag remelting, characterized in that molten slag containing B oxide in an amount equal to or more than the amount of B that is in equilibrium is used
トをエレクトロスラグ再溶解によって製造する際に、一
端の軸部に対応する電極を再溶解する再溶解初期にＢ酸
化物を含まないスラグを使用し、他端の軸部に対応する
電極の再溶解時に、Ｂ酸化物を含まない追加スラグを溶
融スラグに投入することを特徴とする請求項３記載のエ
レクトロスラグ再溶解によるタービンロータシャフトの
製造方法4. A slag containing no B oxide is used in the initial stage of remelting for remelting an electrode corresponding to the shaft portion at one end when manufacturing a turbine rotor shaft having a shaft portion at both ends by electroslag remelting. Then, when the electrode corresponding to the shaft portion at the other end is redissolved, the additional slag containing no B oxide is added to the molten slag to manufacture the turbine rotor shaft by electroslag remelting according to claim 3. Method
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8079285A JP3037611B2 (en) | 1996-03-08 | 1996-03-08 | Method for producing remelted ingot of electroslag and method for producing turbine rotor shaft by remelting electroslag |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8079285A JP3037611B2 (en) | 1996-03-08 | 1996-03-08 | Method for producing remelted ingot of electroslag and method for producing turbine rotor shaft by remelting electroslag |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09239519A true JPH09239519A (en) | 1997-09-16 |
| JP3037611B2 JP3037611B2 (en) | 2000-04-24 |
Family
ID=13685604
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8079285A Expired - Fee Related JP3037611B2 (en) | 1996-03-08 | 1996-03-08 | Method for producing remelted ingot of electroslag and method for producing turbine rotor shaft by remelting electroslag |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3037611B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100657980B1 (en) * | 2004-11-19 | 2006-12-14 | 두산중공업 주식회사 | Method for manufacturing boron containing high cr steel ingot by electro-slag remelting |
| CN110055428A (en) * | 2019-05-31 | 2019-07-26 | 马鞍山市中桥金属材料有限公司 | A kind of method that esr process is boron alloyed |
-
1996
- 1996-03-08 JP JP8079285A patent/JP3037611B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100657980B1 (en) * | 2004-11-19 | 2006-12-14 | 두산중공업 주식회사 | Method for manufacturing boron containing high cr steel ingot by electro-slag remelting |
| CN110055428A (en) * | 2019-05-31 | 2019-07-26 | 马鞍山市中桥金属材料有限公司 | A kind of method that esr process is boron alloyed |
| CN110055428B (en) * | 2019-05-31 | 2020-12-11 | 马鞍山市中桥金属材料有限公司 | Boron alloying method in electroslag remelting process |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3037611B2 (en) | 2000-04-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11603583B2 (en) | Ribbons and powders from high strength corrosion resistant aluminum alloys | |
| RU2490350C2 (en) | METHOD FOR OBTAINING BASIC β-γ-TiAl-ALLOY | |
| CN111961875B (en) | Smelting method for controlling aluminum-titanium burning loss of iron-nickel-based high-temperature alloy electroslag ingot | |
| JPH0225534A (en) | Titanium-aluminum alloy | |
| CN106756081A (en) | The preparation method of big specification Ti Al Nb series alloy fines crystalline substance ingot casting | |
| CN107723517A (en) | A kind of Ti Al based alloys and its application with good increasing material manufacturing forming property | |
| JPH09239519A (en) | Manufacture of electroslag re-melted cast billet, and manufacture of turbine rotor shaft by electroslag re-melting | |
| CN111057911A (en) | Al-Bi monotectic alloy and preparation method thereof | |
| EP0079765B1 (en) | Method of making a lead-calcium-aluminium alloy | |
| JPH09194962A (en) | Slag for electroslag remelting for ni base superalloy material and method for electroslag remelting for the same superalloy material | |
| CN107739888A (en) | A kind of Ti V based alloys and its application with good increasing material manufacturing forming property | |
| JP2565448B2 (en) | Method for producing Ni-Fe based super heat-resistant alloy ingot | |
| JP2001262277A (en) | Low thermal expansion alloy excellent in machinability and its producing method | |
| JP7145411B2 (en) | Method for producing Mg-containing high-Ni alloy | |
| JP2565447B2 (en) | Method for producing ingot of Ni-base super heat-resistant alloy | |
| JP3072199B2 (en) | Method for producing Ni-Fe-based super heat-resistant alloy ingot | |
| JPH11189834A (en) | High strength trolley wire and its manufacture | |
| JP2989053B2 (en) | Method for producing low oxygen Ti-Al alloy and low oxygen Ti-Al alloy | |
| JP3302506B2 (en) | Electroslag remelting electrode and method for producing electroslag remelted steel ingot | |
| JP2622684B2 (en) | Manufacturing method of compound screw rotor for compressor | |
| JPH03257131A (en) | Cutlery material made of ni-based alloy precipitation hardened with intermetallic compound and production thereof | |
| JP3544110B2 (en) | Slag for remelting electroslag and method for producing high cleanliness material using the slag | |
| JPH05345934A (en) | Electrode for remelting electroslag and production of alloy using the electrode | |
| JP3110565B2 (en) | Method of manufacturing working roll for cold rolling | |
| JP3084850B2 (en) | Ingot drawing type electroslag melting method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090225 Year of fee payment: 9 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100225 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100225 Year of fee payment: 10 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110225 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110225 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120225 Year of fee payment: 12 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130225 Year of fee payment: 13 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20140225 Year of fee payment: 14 |
|
| LAPS | Cancellation because of no payment of annual fees |