JPH0612346B2 - Method for measuring the spheroidization rate of graphite in molten cast iron - Google Patents
Method for measuring the spheroidization rate of graphite in molten cast ironInfo
- Publication number
- JPH0612346B2 JPH0612346B2 JP59101360A JP10136084A JPH0612346B2 JP H0612346 B2 JPH0612346 B2 JP H0612346B2 JP 59101360 A JP59101360 A JP 59101360A JP 10136084 A JP10136084 A JP 10136084A JP H0612346 B2 JPH0612346 B2 JP H0612346B2
- Authority
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- Prior art keywords
- graphite
- extracted
- spheroidization rate
- cooling curve
- cast iron
- Prior art date
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N25/00—Investigating or analyzing materials by the use of thermal means
- G01N25/02—Investigating or analyzing materials by the use of thermal means by investigating changes of state or changes of phase; by investigating sintering
- G01N25/04—Investigating or analyzing materials by the use of thermal means by investigating changes of state or changes of phase; by investigating sintering of melting point; of freezing point; of softening point
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- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
- Investigating Or Analyzing Materials Using Thermal Means (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は黒鉛の球状化処理を施した鋳鉄溶湯の黒鉛球状
化率を高精度かつ高速度で測定する方法に関する。TECHNICAL FIELD The present invention relates to a method for measuring the spheroidization rate of graphite in a molten cast iron obtained by subjecting graphite to spheroidization with high accuracy and high speed.
本発明は、鋳鉄溶湯の鋳込み前に、その黒鉛球状化率を
迅速かつ正確に判定するものであるので、鋳鉄の製造効
率及び製品の品質管理の向上に利用できる。INDUSTRIAL APPLICABILITY Since the present invention quickly and accurately determines the graphite spheroidization rate of a cast iron molten metal, it can be used for improving the production efficiency of cast iron and the quality control of products.
［従来技術］ 鋳鉄の製造過程において、黒鉛の球状化率を精度良く制
御することは製品の品質管理の面において非常に重要な
ことである。従来、一般に鋳鉄の黒鉛球状化率を測定す
る方法としては次の様な方法が知られている。[Prior Art] In the production process of cast iron, it is very important to control the spheroidization rate of graphite with high precision in terms of product quality control. Conventionally, the following method is generally known as a method for measuring the spheroidization rate of graphite in cast iron.
第１の方法は同一の球状化処理を施された溶湯から製作
された鋳鉄製品、又は、この鋳鉄製品と同一の条件で鋳
造した供試材の断面の顕微鏡写真により球状化率を判定
する方法である。この方法は、球状化率の測定の確実性
はあるが、測定に長時間要するという欠点がある。又、
注湯後の判定試験のため、品質不良と判定されても、す
でに多数の製品は鋳造されており、この溶湯から形成さ
れた製品は全て不良品とされてしまう。このため製造効
率が極めて悪いという欠点がある。The first method is a method of determining the spheroidization rate by a micrograph of a cross section of a cast iron product manufactured from a molten metal subjected to the same spheroidization treatment, or a sample material cast under the same conditions as this cast iron product. Is. This method has certainty in measuring the spheroidization rate, but has the drawback that the measurement takes a long time. or,
Because of the judgment test after pouring, even if it is judged that the quality is poor, many products have already been cast, and all the products formed from this molten metal are regarded as defective products. Therefore, there is a drawback that the manufacturing efficiency is extremely poor.
第２の方法は、黒鉛の球状化処理を施した後の溶湯の一
部を取出し、この溶湯の冷却曲線を測定し、この冷却曲
線の各種の特徴量を抽出し、これらの特徴量、と予め多
数のサンプルについて測定された黒鉛の球状化率との重
回帰分析法によって求められた関係式を利用して、黒鉛
の球状化率を測定する方法、即ち熱分析法が知られてい
る。しかし、従来の熱分析法は、黒鉛の球状化処理を施
した後の冷却曲線から抽出される特徴量のみを用いたも
のでり、黒鉛の球状化処理を施す前の元湯の冷却曲線か
ら得られる特徴量については何等加味されていなかっ
た。従って、元湯の成分に不均一性がある場合には、黒
鉛の球状化率の測定精度が劣るという欠点が存在した。
本発者等は黒鉛の球状化率は球状化処理を施す前の元湯
の冷極曲線から得られる元湯の初晶温度、元湯の共晶温
度と極めて高い相関関係があることを発見した。本発明
はこのような発見に基づいて成されたものである。The second method is to take out a part of the molten metal after the spheroidizing treatment of graphite, measure the cooling curve of this molten metal, extract various characteristic amounts of this cooling curve, and extract these characteristic amounts. There is known a method for measuring the spheroidization rate of graphite, that is, a thermal analysis method, using a relational expression obtained by a multiple regression analysis method with the spheroidization rate of graphite measured in advance for a large number of samples. However, the conventional thermal analysis method uses only the feature amount extracted from the cooling curve after the spheroidizing treatment of graphite, and from the cooling curve of the original hot water before the spheroidizing treatment of graphite. The feature quantity obtained was not considered at all. Therefore, when the components of the hot water have non-uniformity, the measurement accuracy of the spheroidization rate of graphite is inferior.
The present inventors discovered that the spheroidization rate of graphite has a very high correlation with the eutectic temperature of the original hot water and the eutectic temperature of the original hot water obtained from the cold pole curve of the original hot water before the spheroidizing treatment. did. The present invention has been made based on these findings.
［発明の目的］ そこで本発明はこれらの欠点を改良するために成された
ものであり、黒鉛の球状化処理を施す前の元湯の冷却曲
線から得られる元湯の初晶温度、共晶温度を必須の特徴
量とすることにより黒鉛の球状化率を精度よく、かつ高
速に求めることを目的とする。[Object of the invention] Then, the present invention has been made in order to improve these drawbacks, the primary crystal temperature of the original hot water obtained from the cooling curve of the original hot water before the spheroidizing treatment of graphite, eutectic The purpose is to obtain the spheroidization rate of graphite accurately and at high speed by making temperature an essential feature amount.
［発明の構成］ 本発明は、鋳鉄溶湯の冷却曲線から黒鉛の球状化率と相
関のある特徴量を抽出し、 予め多数のサンプルについて、測定された該特徴量と、
黒鉛球状化率とから、前記特徴量を変数とする黒鉛球状
化率を求める関係式を決定し、 該関係式から黒鉛球状化率を求める熱分析法を用いた鋳
鉄溶湯の黒鉛球状化率の測定方法において、 前記特徴量は、少なくとも、黒鉛の球状化処理を施す前
の元湯の冷却曲線から測定された元湯の初晶温度、元湯
の共晶温度を含むことを特徴とする鋳鉄溶湯の黒鉛球状
化率の測定方法に関する。[Structure of the Invention] The present invention extracts a characteristic amount correlated with the spheroidization rate of graphite from a cooling curve of a cast iron molten metal, and the characteristic amount measured in advance for a large number of samples, and
From the graphite spheroidization rate, a relational expression for obtaining the graphite spheroidization rate with the above-mentioned characteristic variable as a variable is determined, and the graphite spheroidization rate of the cast iron molten metal using the thermal analysis method for determining the graphite spheroidization rate from the relational expression is calculated. In the measurement method, the characteristic amount is at least the primary crystal temperature of the original hot water measured from the cooling curve of the original hot water before spheroidizing the graphite, the cast iron characterized by including the eutectic temperature of the original hot water The present invention relates to a method for measuring the spheroidization rate of graphite in molten metal.
本発明は鋳鉄溶湯の冷却曲線から得られる各種の特徴量
と黒鉛の球状化率との関係式を、各種のサンプルについ
て行なった実験から求め、この実験的に求められた関係
式を用いて、測定試料について冷却曲線を測定し、その
冷却曲線から得られる特徴量から、黒鉛の球状化率を算
出する熱分析法と関連している。本発明はこの様な熱分
析法において、黒鉛の球状化処理を施す前の元湯の冷却
曲線から得られた元湯の初晶温度及び元湯の共晶温度を
上記関係式の必須の変数としていることを特徴としてい
る。上記元湯の初晶温度、元湯の共晶温度以外の他の特
徴量には、球状化処理を施した後の鋳鉄溶湯の冷却曲線
から得られる共晶温度、初晶温度、過冷温度の中から選
択された特徴量を必要とする。The present invention, a relational expression between various characteristic amounts obtained from the cooling curve of the cast iron molten metal and the spheroidization rate of graphite, is obtained from an experiment conducted on various samples, using the relational expression obtained experimentally, This is related to a thermal analysis method in which a cooling curve is measured for a measurement sample, and the spheroidization rate of graphite is calculated from the characteristic amount obtained from the cooling curve. According to the present invention, in such a thermal analysis method, the primary temperature and the eutectic temperature of the original hot water obtained from the cooling curve of the original hot water before the spheroidizing treatment of graphite are the essential variables of the above relational expression. It is characterized by that. Other than the eutectic temperature of the original hot water and the eutectic temperature of the original hot water, the eutectic temperature, the primary crystal temperature, and the supercooling temperature obtained from the cooling curve of the cast iron melt after the spheroidizing treatment are performed. It requires the feature quantity selected from among.
更に具体的に説明すれば、第１態様では、鋳鉄溶湯の冷
却曲線から黒鉛球状化率と相関関係をもつ特徴量を抽出
し、予め多数のサンプルから抽出した前記特徴量と前記
黒鉛球状化率とから前記特徴量を変数とする黒鉛球状化
率を求める関係式を決定し、該関係式から黒鉛球状化率
を求める熱分析法を用いた鋳鉄溶湯の黒鉛球状化率の測
定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥとを前記特徴量として抽出し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４を係数とした場合にＳＧ＝Ｋ１
×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ４とした前記
関係式から前記黒鉛球状化率ＳＧを算出される。More specifically, in the first aspect, the characteristic amount having a correlation with the graphite spheroidizing rate is extracted from the cooling curve of the cast iron molten metal, and the characteristic amount and the graphite spheroidizing rate extracted from a large number of samples in advance are extracted. In the method of measuring the graphite spheroidization rate of the cast iron molten metal by using the thermal analysis method to determine the relational expression for obtaining the graphite spheroidization rate with the characteristic amount as a variable from the The eutectic temperature TE0 and eutectic temperature TE0 of the original melt extracted from the cooling curve of the melt before spheroidizing treatment, and the eutectic temperature TE of the melt extracted from the cooling curve of the melt after graphite spheroidizing treatment Is extracted as the feature amount, and SG = K1 when K1, K2, K3, and K4 are used as coefficients.
The graphite spheroidization rate SG is calculated from the relational expression of × TLO + K2 × TEO + K3 × TE + K4.
第２態様では、鋳鉄溶湯の冷却曲線から黒鉛球状化率と
相関関係をもつ特徴量を抽出し、予め多数のサンプルか
ら抽出した前記特徴量と前記黒鉛球状化率とから前記特
徴量を変数とする黒鉛球状化率を求める関係式を決定
し、該関係式から黒鉛球状化率を求める熱分析法を用い
た鋳鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥ及び初晶温度ＴＬとを前記特徴量として抽出
し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４、Ｋ５を係数とした場合にＳＧ
＝Ｋ１×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ４×Ｔ
Ｌ＋Ｋ５とした前記関係式から前記黒鉛球状化率ＳＧが
算出される。In the second aspect, a characteristic amount having a correlation with the graphite spheroidizing rate is extracted from the cooling curve of the cast iron molten metal, and the characteristic amount is extracted as a variable from the characteristic amount and the graphite spheroidizing rate extracted from a large number of samples in advance. In the method of measuring the graphite spheroidization rate of the cast iron melt using the thermal analysis method to determine the relational expression to determine the graphite spheroidization rate from the relational expression, The primary crystal temperature TLO and eutectic temperature TE0 of the original molten metal extracted from the cooling curve, and the eutectic temperature TE and primary crystal temperature TL of the molten metal extracted from the cooling curve of the molten metal after the graphite spheroidization treatment are described above. SG when it is extracted as a feature amount and K1, K2, K3, K4, and K5 are used as coefficients.
= K1 x TLO + K2 x TEO + K3 x TE + K4 x T
The graphite spheroidization rate SG is calculated from the relational expression L + K5.
第３態様では、鋳鉄溶湯の冷却曲線から黒鉛球状化率と
相関関係をもつ特徴量を抽出し、予め多数のサンプルか
ら抽出した前記特徴量と前記黒鉛球状化率とから前記特
徴量を変数とする黒鉛球状化率を求める関係式を決定
し、該関係式から黒鉛球状化率を求める熱分析法を用い
た鋳鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥ及び過冷温度ＴＣとを前記特徴量として抽出
し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４、Ｋ５を係数とした場合にＳＧ
＝Ｋ１×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ４×Ｔ
Ｃ＋Ｋ５とした前記関係式から前記黒鉛球状化率ＳＧが
算出される。In the third aspect, a characteristic amount having a correlation with the graphite spheroidizing rate is extracted from the cooling curve of the cast iron molten metal, and the characteristic amount is extracted from a large number of samples in advance and the graphite spheroidizing rate is used as a variable. In the method of measuring the graphite spheroidization rate of the cast iron melt using the thermal analysis method to determine the relational expression to determine the graphite spheroidization rate from the relational expression, The primary crystal temperature TLO and eutectic temperature TE0 of the original molten metal extracted from the cooling curve, and the eutectic temperature TE and the supercooling temperature TC of the molten metal extracted from the cooling curve of the molten metal after the graphite spheroidization treatment are described above. SG when it is extracted as a feature amount and K1, K2, K3, K4, and K5 are used as coefficients.
= K1 x TLO + K2 x TEO + K3 x TE + K4 x T
The graphite spheroidization rate SG is calculated from the relational expression with C + K5.
第４態様では、鋳鉄溶湯の冷却曲線から黒鉛球状化率と
相関関係をもつ特徴量を抽出し、予め多数のサンプルか
ら抽出した前記特徴量と前記黒鉛球状化率とから前記特
徴量を変数とする黒鉛球状化率を求める関係式を決定
し、該関係式から黒鉛球状化率を求める熱分析法を用い
た鋳鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥ、初晶温度ＴＬ及び過冷温度ＴＣとを前記特
徴量として抽出し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４、Ｋ５、Ｋ６を係数とした場合
にＳＧ＝Ｋ１×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ
４×ＴＬ＋Ｋ５×ＴＣ＋Ｋ６とした前記関係式から前記
黒鉛球状化率ＳＧを算出される。又、その他の特徴量と
して、過冷温度から共晶温度に達するまでに要した時
間、共晶温度と過冷温度との温度差、初晶温度から過冷
温度に達する時間、過冷温度継続時間、共晶温度の継続
時間等が考えられる。黒鉛の球状化率は第１の望ましい
実施態様においては、元湯の初晶温度、元湯の共晶温
度、処理後の溶湯の共晶温度の３つを特徴量として求め
るものである。即ち、１次近似によれば、次式で求める
ことができる。In the fourth aspect, a characteristic amount having a correlation with the graphite spheroidizing rate is extracted from the cooling curve of the cast iron molten metal, and the characteristic amount is extracted as a variable from the characteristic amount and the graphite spheroidizing rate extracted from a large number of samples in advance. In the method of measuring the graphite spheroidization rate of the cast iron melt using the thermal analysis method to determine the relational expression to determine the graphite spheroidization rate from the relational expression, Primary crystal temperature TLO and eutectic temperature TE0 of the original melt extracted from the cooling curve, and eutectic temperature TE, primary crystal temperature TL and supercooling of the melt extracted from the cooling curve of the melt after the graphite spheroidization treatment. When the temperature TC and the characteristic amount are extracted and K1, K2, K3, K4, K5, and K6 are used as coefficients, SG = K1 × TLO + K2 × TEO + K3 × TE + K
The graphite spheroidization rate SG is calculated from the relational expression of 4 × TL + K5 × TC + K6. In addition, as other features, the time required to reach the eutectic temperature from the supercooling temperature, the temperature difference between the eutectic temperature and the supercooling temperature, the time to reach the supercooling temperature from the primary crystal temperature, the supercooling temperature continuation The time and the duration of the eutectic temperature may be considered. In the first preferred embodiment, the spheroidization rate of graphite is obtained by using three characteristics, namely, the primary crystal temperature of the original hot water, the eutectic temperature of the original hot water, and the eutectic temperature of the molten metal after the treatment. That is, according to the first-order approximation, it can be obtained by the following equation.
ＳＧ＝Ａ・ＴＬＯ＋Ｂ・ＴＥＯ＋Ｃ・ＴＥ＋Ｐ……
（１） ここで、ＳＧは黒鉛球状化率であり、ＴＬＯ、ＴＥＯは
それぞれ元湯の冷却曲線における初晶温度及び共晶温度
である。又ＴＥは黒鉛の球状化処理を施した後の溶湯の
冷却曲線から得られる共晶温度である。更にＡ、Ｂ、
Ｃ、Ｐはそれぞれ各変数の系数である。これらの係数は
予め多数のサンプルについて測定した結果から求められ
る。即ち、この関数の係数は、他の方法（例えば日本鋳
物協会法［ＮＩＫ法］）で測定された黒鉛の球状化率
と、それぞれの上記変数との相関関数を測定し、重回帰
分析法により決定される。上記関数は、１次式を用いた
が、他の２次、３次等のn 次式を用いることもできる。SG = A ・ TLO + B ・ TEO + C ・ TE + P ……
(1) Here, SG is the spheroidization ratio of graphite, and TLO and TEO are the primary crystal temperature and the eutectic temperature in the cooling curve of the original molten metal, respectively. Further, TE is a eutectic temperature obtained from the cooling curve of the molten metal after the graphite is spheroidized. Furthermore, A, B,
C and P are coefficients of each variable. These coefficients are obtained from the results obtained by measuring a large number of samples in advance. That is, for the coefficient of this function, the correlation function between the spheroidization rate of graphite measured by another method (for example, the Japan Foundry Association method [NIK method]) and each of the above variables was measured, and the multiple regression analysis method was used. It is determined. Although the above function uses a linear expression, other quadratic expressions such as quadratic and cubic may be used.
他の望ましい実施態様項においては、黒鉛の球状化率を
求めるのに、更に処理後の溶湯の冷却曲線における初晶
温度が加味される。即ち、球状化率を求める式は次式に
よって与えられる。In another preferred embodiment, the primary crystal temperature in the cooling curve of the molten metal after the treatment is further taken into consideration in determining the spheroidization rate of graphite. That is, the formula for obtaining the spheroidization rate is given by the following formula.
ＳＧ＝Ａ・ＴＬＯ＋Ｂ・ＴＥＯ＋Ｃ・ＴＥ＋Ｄ・ＴＬ＋
Ｐ ……（２） ここでＴＬは処理後の溶湯の冷却曲線から得られる初晶
温度である。又Ｄはその係数である。更に他の望ましい
実施態様においては、球状化率は次式で与えられる。SG = A ・ TLO + B ・ TEO + C ・ TE + D ・ TL +
P (2) Here, TL is the primary crystal temperature obtained from the cooling curve of the molten metal after the treatment. D is the coefficient. In yet another preferred embodiment, the spheroidization rate is given by:
ＳＧ＝Ａ・ＴＬＯ＋Ｂ・ＴＥＯ＋Ｃ・ＴＥ＋Ｄ・ＴＬ＋
Ｅ・ＴＣ＋Ｐ……（３） ここでＴＣは処理後の溶湯の冷却曲線における過冷温度
であり、Ｅはその係数である。SG = A ・ TLO + B ・ TEO + C ・ TE + D ・ TL +
E · TC + P (3) Here, TC is the supercooling temperature in the cooling curve of the molten metal after the treatment, and E is the coefficient thereof.
ここで、初晶温度、過冷温度、共晶温度の検出は、冷却
曲線の停滞点を求めることによって行なされる。この停
滞点とは冷却曲線の微分係数が一定の範囲に存在する区
間に存在する点である。以下、この区間を停滞区間とい
う。初晶、過冷、共晶の区別は、停滞区間の現れる順序
と、停滞時間と停滞区間を脱出した後、冷却曲線が上向
きか下向きか、いずれに変移するかによって決定され
る。例えば、取り出された溶湯２５０ｇ、シェル型丸棒
３５mmφ×４０mmの条件で停滞区間は、冷却曲線の微分
係数が±２．５゜Ｆ／ｓｅｃの範囲に存在する時間が
２．４秒以上継続した範囲としている。又初晶温度は第
１番目の停滞区間であって停滞区間が１６秒より小さ
く、停滞区間を脱出した後曲線が下向きに推移する停滞
区間の中間値として検出される。又、過冷温度は、第
１、又は第２番目の停滞区間であって、停滞区間を脱出
した後、曲線が上向きに推移する停滞区間の最小値、又
は、上記条件を満足しない場合には、共晶温度が検出さ
れる停滞区間のうち、共晶温度よりも先に現れる最小値
として検出される。Here, the primary crystal temperature, the supercooling temperature, and the eutectic temperature are detected by obtaining the stagnation point of the cooling curve. The stagnation point is a point existing in a section where the differential coefficient of the cooling curve exists in a certain range. Hereinafter, this section is referred to as a stagnant section. The distinction between primary crystal, supercooling, and eutectic is determined by the order in which stagnant sections appear, the stagnant time, and whether the cooling curve changes upward or downward after exiting the stagnant section. For example, in the stagnant section under the condition of 250 g of molten metal taken out and 35 mmφ × 40 mm of shell type round bar, the time during which the differential coefficient of the cooling curve is within ± 2.5 ° F / sec continues for 2.4 seconds or more. It has a range. Further, the primary crystal temperature is the first stagnant section, the stagnant section is smaller than 16 seconds, and is detected as an intermediate value of the stagnant section in which the curve shifts downward after exiting the stagnant section. Further, the supercooling temperature is the first or second stagnation section, and the minimum value of the stagnation section where the curve moves upward after exiting the stagnation section, or when the above conditions are not satisfied , Of the stagnation sections where the eutectic temperature is detected, the eutectic temperature is detected as the minimum value that appears earlier than the eutectic temperature.
又、共晶温度は、第２番目、又は第３番目の停滞区間で
あって、停滞区間を脱出した後、曲線が下向きに推移す
る停滞区間の最大値、又は第１番目であって１６秒以上
継続する停滞区間の最大値として検出される。The eutectic temperature is the second or third stagnation section, the maximum value of the stagnation section in which the curve shifts downward after exiting the stagnation section, or the first value is 16 seconds. It is detected as the maximum value of the stagnation section that continues above.
［実施例］ 本発明方法は、計算機装置により実施することができ
る。[Example] The method of the present invention can be implemented by a computer device.
第１図は本発明を実施する測定装置の構成を示したブロ
ックダイヤグラムである。２は溶湯の一部を取出してそ
の冷却曲線を測定するためのカップであり、そのカップ
２の底部にはアルメルークロメルから成る熱電対４が設
けられ、熱電対４によって発生された起電力は導線を介
して温度計６に入力する。温度計６はアナログ量の起電
力を０．４秒ごとにサンプリングし、デジタル信号に変
換し、２進化＋進数（ＢＣＤ）で表わされた符号化コー
ドとしてパラレル／シリアル変換器８に出力する。パラ
レル／シリアル変換器８はＢＣＤデータをシリアルデー
タに変換し、マイクロコンピュータ１０のシリアルデー
タ入力ポートに出力する。マイクロコンピュータ１０に
は所定の測定結果を出力するプリンタ１２及びＣＲＴ１
６が接続され、所定のプログラム及び、計算式とその係
数を記憶したフロッピィディスク装置１４が接続されて
いる。FIG. 1 is a block diagram showing the configuration of a measuring apparatus for carrying out the present invention. Reference numeral 2 is a cup for taking out a part of the molten metal and measuring the cooling curve thereof. A thermocouple 4 made of alumel-chromel is provided at the bottom of the cup 2, and the electromotive force generated by the thermocouple 4 is Input to the thermometer 6 via a lead wire. The thermometer 6 samples an electromotive force of an analog amount every 0.4 seconds, converts it into a digital signal, and outputs it to the parallel / serial converter 8 as an encoded code represented by a binary code + a binary number (BCD). . The parallel / serial converter 8 converts the BCD data into serial data and outputs it to the serial data input port of the microcomputer 10. A printer 12 and a CRT 1 for outputting a predetermined measurement result to the microcomputer 10.
6 is connected, and a floppy disk device 14 storing a predetermined program, a calculation formula and its coefficient is connected.
本実施例においては、冷却曲線から測定される初晶温
度、過冷温度、共晶温度は、前述した条件よって決定し
た。第２図は黒鉛の球状化処理を施す前の元湯の冷却曲
線を示すものである。この冷却曲線から元湯の初晶温度
ＴＬＯ＝２０７７゜Ｆ、元湯の共晶温度ＴＥＯ＝２０４
１゜Ｆが得られた。In this example, the primary crystal temperature, the supercooling temperature, and the eutectic temperature measured from the cooling curve were determined under the conditions described above. FIG. 2 shows the cooling curve of the hot water before the spheroidizing treatment of graphite. From this cooling curve, the primary temperature TLO of the hot water is 2077 ° F and the eutectic temperature TEO of the hot water is 204.
1 ° F. was obtained.
第１実施例として、処理後の溶湯の冷却曲線から共晶温
度を抽出した場合を示す。又第３図は黒鉛の球状化処理
を施した後の冷却曲線の一例である。この冷却曲線から
処理後の溶湯の共晶温度ＴＥ＝２０９４゜Ｆが得られ
た。これらの数値を用いて次式により、球状化率を求め
た。As a first example, a case where the eutectic temperature is extracted from the cooling curve of the molten metal after the treatment is shown. FIG. 3 is an example of a cooling curve after the spheroidizing treatment of graphite. From this cooling curve, a eutectic temperature TE = 2094 ° F of the molten metal after the treatment was obtained. The spheroidization rate was calculated by the following equation using these numerical values.
ＳＧ＝０．０９７０１×ＴＬＯ＋１．２３０９５×ＴＥ
Ｏ−２．６６８０２×ＴＥ×２９２８．３……
（４） 上記の式から球状化率は８２％が得られた。この測定誤
差は８％である。SG = 0.09701 × TLO + 1.23095 × TE
O-2.66802 × TE × 2928.3 ……
(4) From the above formula, a spheroidization rate of 82% was obtained. This measurement error is 8%.
第２実施例として処理後の溶湯の冷却曲線から初晶温度
及び共晶温度を抽出した場合を示す。第４図は、１試料
について冷却曲線を測定したものである。この球状化処
理後の溶湯の冷却曲線から初晶温度ＴＬ＝２１１７゜
Ｆ、共晶温度ＴＥ＝２０９５゜Ｆが得られた。この結果
を用いて、次式により球状化率を求めた。As a second example, a case where the primary crystal temperature and the eutectic temperature are extracted from the cooling curve of the molten metal after the treatment is shown. FIG. 4 shows the cooling curve measured for one sample. From the cooling curve of the molten metal after the spheroidizing treatment, the primary crystal temperature TL = 2117 ° F and the eutectic temperature TE = 2095 ° F were obtained. Using this result, the spheroidization rate was calculated by the following formula.
ＳＧ＝０．９５４７７×ＴＬＯ＋１０．４１９７４×Ｔ
ＥＯ−６．１０６３４ＴＬ＋６．７９１９７×ＴＥ−２
４５４３．１ ……（５） この式から球状化率ＳＧは４７％が得られた。この測定
誤差は８％である。SG = 0.95477 × TLO + 10.41974 × T
EO-610634TL + 6.79197 x TE-2
4543.1 (5) From this formula, a spheroidization rate SG of 47% was obtained. This measurement error is 8%.
第３実施例として、処理後の溶湯の冷却曲線から過冷温
度及び共晶温度を抽出した場合を示す。第５図は別の試
料の球状化処理を施した溶湯の冷却曲線である。この冷
却曲線から過冷温度ＴＣ＝２０７４゜Ｆ、共晶温度ＴＥ
＝２０９６゜Ｆが得られた。As a third example, a case where the supercooling temperature and the eutectic temperature are extracted from the cooling curve of the molten metal after the treatment is shown. FIG. 5 is a cooling curve of a molten metal which has been subjected to spheroidizing treatment of another sample. From this cooling curve, the supercooling temperature TC = 2074 ° F., the eutectic temperature TE
= 2096 ° F was obtained.
ＳＧ＝−０．４９９２１×ＴＬＯ＋０．１３２９４×Ｔ
ＥＯ＋０．６３９０８×ＴＣ−１．４９７９２×ＴＥ＋
２６１７．８ ……（６） この式から球状化率３７％が得られた。この測定誤差は
８％である。SG = −0.49921 × TLO + 0.13294 × T
EO + 0.63908 × TC-1.49792 × TE +
2617.8 (6) From this formula, a spheroidization rate of 37% was obtained. This measurement error is 8%.
次に第４実施例として、元湯の初晶温度ＴＬＯ＝２１２
３゜Ｆ、元湯の共晶温度ＴＥＯ＝２０３８゜Ｆ、であっ
て、処理後の溶湯の冷却曲線から初晶温度、過冷温度及
び共晶温度を検出した場合を示す。又第６図は別の球状
化処理を施した溶湯の冷却曲線である。この曲線から初
晶温度ＴＬ＝２１０１゜Ｆ、過冷温度ＴＣ＝２０８０゜
Ｆ、共晶温度ＴＥ＝２０８３゜Ｆが得られた。Next, as the fourth embodiment, the primary crystal temperature TLO of the original hot water is TLO = 212.
It shows the case where the eutectic temperature TEO of the original melt is TEO = 2038 ° F and the primary crystal temperature, the supercooling temperature and the eutectic temperature are detected from the cooling curve of the melt after the treatment. Further, FIG. 6 is a cooling curve of the molten metal subjected to another spheroidizing treatment. From this curve, a primary crystal temperature TL = 2101 ° F, a supercooling temperature TC = 2080 ° F, and a eutectic temperature TE = 2083 ° F were obtained.
この場合には次式より球状化率を求めることができる。In this case, the spheroidization rate can be calculated from the following equation.
ＳＧ＝０．０６１７７×ＴＬＯ＋３．３００３３×ＴＥ
Ｏ−０．３９１５６ＴＬ＋２．０８１９７×ＴＣ−４．
１３４５９×ＴＥ−１６８０．３……
（７） 上式により球状化率７２．４％が得られた。測定誤差８
％である。SG = 0.06177 × TLO + 3.30033 × TE
O-0.39156TL + 2.08197xTC-4.
13459 × TE-1680.3 ……
(7) A spheroidization rate of 72.4% was obtained from the above equation. Measurement error 8
%.
［発明の効果］ 以上要するに本発明は、黒鉛の球状化率を求める熱分析
法において、黒鉛の球状化処理を施す前の元湯の冷却曲
線から得られる初晶温度及び共晶温度を少なくとも必須
の変数として含む関係式により黒鉛の球状化率を測定す
る方法である。従って本発明によれば、元湯の成分の違
いによる球状化率の変化を正確に補償することができ
る。これらの方法は、鋳造前の溶湯の状態で測定してい
るために不良品の発生が未然に防止でき、従って製造効
率が向上するという効果がある。[Effects of the Invention] In summary, according to the present invention, in the thermal analysis method for determining the spheroidization rate of graphite, at least the primary crystal temperature and the eutectic temperature obtained from the cooling curve of the hot water before the spheroidization treatment of graphite are essential. Is a method of measuring the spheroidization rate of graphite by a relational expression including as a variable of. Therefore, according to the present invention, it is possible to accurately compensate for the change in the spheroidization rate due to the difference in the components of the hot water. Since these methods measure the molten metal before casting, the production of defective products can be prevented in advance, and therefore the manufacturing efficiency can be improved.
例えば、今、あるロットについて、元湯のＴＬＯ、ＴＥ
Ｏと黒鉛球状化処理後の溶湯のＴＥなどを計測し、黒鉛
球状化率ＳＧを求めた後、他のロットにおいてその元湯
のＴＬＯ、ＴＥＯだけを再度、測定し、上式にあてはめ
れば、鋳鉄溶湯については再度、検査しなくても元湯の
成分のばらつきによる黒鉛球状化率ＳＧの変動を補正す
ることができる。For example, for a certain lot, TLO and TE of Motoyu
After measuring TE and TE of the molten metal after spheroidizing graphite and obtaining the graphite spheroidizing rate SG, in other lots, only TLO and TEO of the original molten metal are measured again, and if applied to the above formula With respect to the cast iron molten metal, it is possible to correct the variation of the graphite spheroidization ratio SG due to the variation of the components of the original molten metal without inspecting it again.
すなわち、元湯の成分がばらつけばＴＬＯ、ＴＥＯが変
化するので、ＴＬＯ、ＴＥＯを再度計測して算出式から
再度黒鉛球状化率ＳＧを算出すれば、元湯の成分のばら
つきによる黒鉛球状化率ＳＧの変動を低減することがで
き、黒鉛球状化処理前に黒鉛球状化率ＳＧが不良という
ことを推定して、資材、工数の無駄を防止できる。That is, since TLO and TEO will change if the components of the source water vary, if TLO and TEO are measured again and the graphite spheroidization rate SG is calculated again from the calculation formula, the graphite spheroidization due to the variation of the components of the source water will occur. The fluctuation of the rate SG can be reduced, and it can be estimated that the graphite spheroidization rate SG is poor before the graphite spheroidization treatment, and waste of materials and man-hours can be prevented.
第１図は本発明方法を実施するための測定装置の構成を
示したブロックダイヤグラムである。第２図は黒鉛の球
状化処理を施す前の元湯の冷却曲線を測定したグラフで
ある。第３図、第４図、第５図及び第６図は黒鉛の球状
化処理を施した後の溶湯の冷却曲線を測定したグラフで
ある。FIG. 1 is a block diagram showing the configuration of a measuring apparatus for carrying out the method of the present invention. FIG. 2 is a graph in which the cooling curve of the hot water before the spheroidizing treatment of graphite is measured. FIG. 3, FIG. 4, FIG. 5 and FIG. 6 are graphs of measured cooling curves of the molten metal after the spheroidizing treatment of graphite.
Claims (4)
関関係をもつ特徴量を抽出し、予め多数のサンプルから
抽出した前記特徴量と前記黒鉛球状化率とから前記特徴
量を変数とする黒鉛球状化率を求める関係式を決定し、
該関係式から黒鉛球状化率を求める熱分析法を用いた鋳
鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥとを前記特徴量として抽出し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４を係数とした場合にＳＧ＝Ｋ１
×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ４とした前記
関係式から前記黒鉛球状化率ＳＧを算出することを特徴
とする鋳鉄溶湯の黒鉛球状化率の測定方法。1. A feature quantity having a correlation with a graphite spheroidization rate is extracted from a cooling curve of a cast iron molten metal, and the feature quantity is set as a variable from the feature quantity extracted from a large number of samples and the graphite spheroidization rate. Determine the relational expression to obtain the graphite spheroidization rate,
In the method for measuring the graphite spheroidization rate of a cast iron melt using a thermal analysis method for obtaining the graphite spheroidization rate from the relational expression, the primary crystal temperature of the original hot water extracted from the cooling curve of the original hot water before the graphite spheroidization treatment When TLO and the eutectic temperature TE0 and the eutectic temperature TE of the molten metal extracted from the cooling curve of the molten metal after the graphite spheroidizing treatment are extracted as the characteristic amounts, and K1, K2, K3, and K4 are used as coefficients. SG = K1
A method for measuring the spheroidization rate of graphite in a cast iron melt, comprising calculating the spheroidization rate SG of the graphite from the above relational expression of × TLO + K2 × TEO + K3 × TE + K4.
関関係をもつ特徴量を抽出し、予め多数のサンプルから
抽出した前記特徴量と前記黒鉛球状化率とから前記特徴
量を変数とする黒鉛球状化率を求める関係式を決定し、
該関係式から黒鉛球状化率を求める熱分析法を用いた鋳
鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥ及び初晶温度ＴＬとを前記特徴量として抽出
し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４、Ｋ５を係数とした場合にＳＧ
＝Ｋ１×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ４×Ｔ
Ｌ＋Ｋ５とした前記関係式から前記黒鉛球状化率ＳＧを
算出することを特徴とする鋳鉄溶湯の黒鉛球状化率の測
定方法。2. A feature quantity having a correlation with a graphite spheroidization rate is extracted from a cooling curve of a cast iron molten metal, and the feature quantity is extracted from a large number of samples in advance and the graphite spheroidization rate is used as a variable. Determine the relational expression to obtain the graphite spheroidization rate,
In the method for measuring the graphite spheroidization rate of a cast iron melt using a thermal analysis method for obtaining the graphite spheroidization rate from the relational expression, the primary crystal temperature of the original hot water extracted from the cooling curve of the original hot water before the graphite spheroidization treatment TLO and eutectic temperature TE0, and eutectic temperature TE and primary crystal temperature TL of the melt extracted from the cooling curve of the melt after the graphite spheroidization treatment are extracted as the characteristic amounts, and K1, K2, K3, and K4 are extracted. , SG when K5 is a coefficient
= K1 x TLO + K2 x TEO + K3 x TE + K4 x T
A method for measuring the spheroidization rate of graphite in molten cast iron, comprising calculating the spheroidization rate SG of the graphite from the relational expression L + K5.
関関係をもつ特徴量を抽出し、予め多数のサンプルから
抽出した前記特徴量と前記黒鉛球状化率とから前記特徴
量を変数とする黒鉛球状化率を求める関係式を決定し、
該関係式から黒鉛球状化率を求める熱分析法を用いた鋳
鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥ及び過冷温度ＴＣとを前記特徴量として抽出
し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４、Ｋ５を係数とした場合にＳＧ
＝Ｋ１×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ４×Ｔ
Ｃ＋Ｋ５とした前記関係式から前記黒鉛球状化率ＳＧを
算出することを特徴とする鋳鉄溶湯の黒鉛球状化率の測
定方法。3. A feature quantity having a correlation with a graphite spheroidization rate is extracted from a cooling curve of a cast iron molten metal, and the feature quantity is a variable from the feature quantity and the graphite spheroidization rate extracted in advance from a large number of samples. Determine the relational expression to obtain the graphite spheroidization rate,
In the method for measuring the graphite spheroidization rate of a cast iron melt using a thermal analysis method for obtaining the graphite spheroidization rate from the relational expression, the primary crystal temperature of the original hot water extracted from the cooling curve of the original hot water before the graphite spheroidization treatment The TLO and the eutectic temperature TE0, and the eutectic temperature TE and the supercooling temperature TC of the melt extracted from the cooling curve of the melt after the graphite spheroidizing treatment are extracted as the characteristic amounts, and K1, K2, K3, and K4 are extracted. , SG when K5 is a coefficient
= K1 x TLO + K2 x TEO + K3 x TE + K4 x T
A method for measuring the graphite spheroidization rate of a cast iron molten metal, which comprises calculating the graphite spheroidization rate SG from the above relational expression where C + K5.
関関係をもつ特徴量を抽出し、予め多数のサンプルから
抽出した前記特徴量と前記黒鉛球状化率とから前記特徴
量を変数とする黒鉛球状化率を求める関係式を決定し、
該関係式から黒鉛球状化率を求める熱分析法を用いた鋳
鉄溶湯の黒鉛球状化率の測定方法において、 黒鉛球状化処理前の元湯の冷却曲線から抽出された前記
元湯の初晶温度ＴＬＯ及び共晶温度ＴＥ０と、黒鉛球状
化処理後の溶湯の冷却曲線から抽出された前記溶湯の共
晶温度ＴＥ、初晶温度ＴＬ及び過冷温度ＴＣとを前記特
徴量として抽出し、 Ｋ１、Ｋ２、Ｋ３、Ｋ４、Ｋ５、Ｋ６を係数とした場合
にＳＧ＝Ｋ１×ＴＬＯ＋Ｋ２×ＴＥＯ＋Ｋ３×ＴＥ＋Ｋ
４×ＴＬ＋Ｋ５×ＴＣ＋Ｋ６とした前記関係式から前記
黒鉛球状化率ＳＧを算出することを特徴とする鋳鉄溶湯
の黒鉛球状化率の測定方法。4. A feature quantity having a correlation with a graphite spheroidization rate is extracted from a cooling curve of a cast iron molten metal, and the feature quantity is extracted from a large number of samples in advance and the graphite spheroidization rate is used as a variable. Determine the relational expression to obtain the graphite spheroidization rate,
In the method for measuring the graphite spheroidization rate of a cast iron melt using a thermal analysis method for obtaining the graphite spheroidization rate from the relational expression, the primary crystal temperature of the original hot water extracted from the cooling curve of the original hot water before the graphite spheroidization treatment TLO and the eutectic temperature TE0, and the eutectic temperature TE, the primary crystal temperature TL and the supercooling temperature TC of the melt extracted from the cooling curve of the melt after the graphite spheroidizing treatment are extracted as the characteristic amounts, K1, SG = K1 × TLO + K2 × TEO + K3 × TE + K when K2, K3, K4, K5, and K6 are used as coefficients.
A method for measuring the spheroidization rate of graphite in a cast iron melt, comprising calculating the spheroidization rate SG of the graphite from the relational expression of 4 × TL + K5 × TC + K6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59101360A JPH0612346B2 (en) | 1984-05-18 | 1984-05-18 | Method for measuring the spheroidization rate of graphite in molten cast iron |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59101360A JPH0612346B2 (en) | 1984-05-18 | 1984-05-18 | Method for measuring the spheroidization rate of graphite in molten cast iron |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60244845A JPS60244845A (en) | 1985-12-04 |
| JPH0612346B2 true JPH0612346B2 (en) | 1994-02-16 |
Family
ID=14298663
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59101360A Expired - Lifetime JPH0612346B2 (en) | 1984-05-18 | 1984-05-18 | Method for measuring the spheroidization rate of graphite in molten cast iron |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0612346B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SE466059B (en) * | 1990-02-26 | 1991-12-09 | Sintercast Ltd | PROCEDURES FOR CONTROL AND ADJUSTMENT OF PRIMARY NUCLEAR FORM |
| CN104049069B (en) * | 2014-06-13 | 2016-02-10 | 清华大学 | A kind of microstructure of grey cast iron performance stokehold fast assessing method |
| CN106127821A (en) * | 2016-07-01 | 2016-11-16 | 昆明理工大学 | A kind of method based on form factor quantitative Analysis spheroidal graphite cast-iron Oxygen potential |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE2929693C2 (en) * | 1979-07-21 | 1981-05-07 | Ströhlein GmbH & Co, 4000 Düsseldorf | Device for taking a molten sample of metal or metal alloys and for measuring the cooling curve of the sample |
| JPS596385A (en) * | 1982-07-04 | 1984-01-13 | Sankyo Alum Ind Co Ltd | Method and apparatus for subjecting conveying object to surface treatment |
-
1984
- 1984-05-18 JP JP59101360A patent/JPH0612346B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60244845A (en) | 1985-12-04 |
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