EP0004819B1 - Procédé de préparation d'alliages ferreux permettant d'améliorer notamment leurs propriétés mécaniques grâce à l'emploi de lanthane et alliages ferreux obtenus par ce procédé - Google Patents

Procédé de préparation d'alliages ferreux permettant d'améliorer notamment leurs propriétés mécaniques grâce à l'emploi de lanthane et alliages ferreux obtenus par ce procédé Download PDF

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Publication number
EP0004819B1
EP0004819B1 EP79400224A EP79400224A EP0004819B1 EP 0004819 B1 EP0004819 B1 EP 0004819B1 EP 79400224 A EP79400224 A EP 79400224A EP 79400224 A EP79400224 A EP 79400224A EP 0004819 B1 EP0004819 B1 EP 0004819B1
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EP
European Patent Office
Prior art keywords
lanthanum
alloy
weight
inoculating
incorporated
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
Application number
EP79400224A
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German (de)
English (en)
French (fr)
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EP0004819A1 (fr
Inventor
Mario Gorgerino
Daniel Videau
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Universelle D'acetylene et D'electro-Metallurgie Cie
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Universelle D'acetylene et D'electro-Metallurgie Cie
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Publication of EP0004819A1 publication Critical patent/EP0004819A1/fr
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Publication of EP0004819B1 publication Critical patent/EP0004819B1/fr
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00—Refining of pig-iron; Cast iron
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C35/00—Master alloys for iron or steel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C22C37/04—Cast-iron alloys containing spheroidal graphite
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60

Definitions

  • the present invention relates generally to the use of lanthanum when developing ferrous alloys such as lamellar cast iron and / or spheroidal graphite, or steels.
  • the present invention relates to a process for the preparation of ferrous alloys making it possible to improve their mechanical properties thanks to the use of lanthanum, in particular in the form of inoculating alloys with a low cerium content or generally with a low content of Rare Earths (including cerium), that is to say with a lanthanum / Rare Earths (except lanthanum) weight ratio at least greater than 100/1.
  • the invention also relates to alloys inoculating with lanthanum for implementing the method as well as the ferrous alloys obtained by the method of the invention.
  • the method of the invention makes it possible to reduce or eliminate some of the defects of ferrous alloys such as pitting, cavities or shrinkage, carbides in spheroidal graphite cast irons to eliminate the presence of carbides in gray lamellar cast iron; improve the flowability, the rolling ability and / or reduce the anisotropy of steels.
  • Pitting and cavities are two major defects affecting molded parts, in particular spheroidal graphite cast irons. These cavities are also called “shrinkage" and constitute the defect type B 221 of the international classification of foundry defects.
  • the bites mentioned above are generally located under the skin of the part and are revealed by shot peening thereof and constitute the defect type B 123 of the international classification of foundry defects.
  • Anisotropy constitutes a defect in steels which often have different mechanical properties in the longitudinal direction compared to the transverse direction, in particular in resilience.
  • Magnesium is added either in the form of pure metal, or more frequently in the form of Fe-Si-Mg alloys. Some of these latter alloys contain cerium (0.2 to 0.4% of the alloy) which is intended to combat the possible effect of the elements Pb, Bi, As, all anti-nodulizing elements.
  • the cast iron thus treated solidifies according to the two diagrams "Fe-GF 3 " and "Fe-graphite".
  • Alexander aims to replace magnesium with lanthanum as an agent which promotes the formation, in cast iron, of spheroidal graphite.
  • lanthanum is not intended to increase the density but simply to improve the flowability, the rolling ability and the isotropy of said steels and this is achieved by adding lanthanum as a post alloy -inoculant after prior deoxidation with aluminum.
  • the present invention therefore aims to eliminate the aforementioned drawbacks and to provide a solution which makes it possible to reduce or eliminate certain defects in ferrous alloys such as pitting, cavities in spheroidal graphite cast iron, carbides in lamellar cast iron, anisotropy of steels, which is usable in industrial practice and which allows as much as possible to improve the mechanical properties of said ferrous alloys.
  • the solution consists according to the invention in a process for the preparation of ferrous alloys characterized in that it comprises the incorporation, as an inoculating alloy or in the case of steels as a post-inoculating alloy after prior deoxidation with aluminum, d '' at least 0.0001% to 0.01% by weight of lanthanum to said ferrous alloy during its preparation, the lanthanum being incorporated either in the form of lanthanum-metal, or of a lanthanum compound or of a lanthanum alloy can be obtained by the use of lanthanum alone or combined with other Rare Earths (including cerium) provided that the lanthanum / Rare Earths (except lanthanum) weight ratio in the said alloy or lanthanum compound is at least higher at 100/1.
  • the lanthanum can be incorporated in the form of an alloy (s) with any metal capable of forming a homogeneous compound with the lanthanum, that is to say having a solubility diagram with the lanthanum alone or combined with other Rare Earths in a proportion of 0.01 to 90% by weight; or in the form of compounds such as chloride, fluoride, oxide obtained from lanthanides, or their mixtures, insofar as the weight ratio lanthanum / Rare Earths (except lanthanum) is greater than 100/1.
  • lanthanum in the form of a lanthanum pure metal preferably having a purity greater than 99%.
  • the particularly preferred lanthanum inoculating alloys of the present invention are alloys based on Si-La-AI, La-Ni, La-Fe-Si, La-Fe-Mn, Si-Ca-Mg-La, La-Cr, Si-La-Mn and where the iron can constitute the balance.
  • these lanthanum inoculating alloys contain other Rare Earths, including cerium, the above-mentioned lanthanum / Rare Earths ratio (except lanthanum) must in all cases be satisfied.
  • certain defects in the cast iron are reduced or eliminated such as defects in the form of pits and cavities or shrinkage and the anisotropy of the steels is reduced, thereby making it possible to obtain ferrous alloys having better properties. mechanical.
  • lanthanum in the form of composite alloys (nodulizers, inoculants, desulphurizers) thus makes it possible to obtain a greater purification of the bath in oxygen and in sulfur which leads to a greater ferritization of the matrix and makes it possible to improve the mechanical characteristics of the ferrous alloys obtained.
  • cerium in relatively large quantities, that is to say already from about 1%, alone or in combination with other Rare Earths, except lanthanum, compared to the proportion lanthanum, as in the case of the mischmetal used before, practically does not make it possible to obtain the improvements obtained with the lanthanum according to the present invention having a low content of cerium because the Applicant has discovered that cerium has a harmful and antagonistic effect on lanthanum which manifests itself as soon as the cerium content is already around 1% compared to the proportion of lanthanum.
  • FIGS. 1 to 6 represent solidification curves of spheroidal graphite cast iron in which the temperature is mentioned on the ordinate while the time is mentioned on the abscissa.
  • Figures 7 to 10 show your cavities or recesses obtained on parts prepared according to the prior art ( Figures 7, 9 and 10) and according to the present invention ( Figure 8).
  • the contents of the components are given as a percentage by weight.
  • This font is produced without inoculation and serves as a reference.
  • the solidification curve obtained on a MECI crucible, with Cr-Ni couple for such a reference cast iron is represented in FIG. 1.
  • This MECI crucible does not modify the solidification of the ingot and in particular ensures solidification quite comparable to that of a piece in a sand mold.
  • the eutectic level is identifiable by an anomaly in the cooling curve which is characterized by a change in inflection of the recorded curve (see Figure 1).
  • the solidification curve obtained, using a MECI crucible, is shown in FIG. 3.
  • the parts obtained have appearance defects such as cavities.
  • the solidification curve shown in FIG. 4 is obtained, which shows an elongation of the solidification interval of the order of 30% and an increase in the temperature of the transformation plateau of the order of 10 ° C.
  • the parts obtained are devoid of cavity.
  • the parts cast with the alloy of the present invention are practically sound, the weights have only a slight dendritic shrinkage while the parts cast according to the prior method have cavities and pits.
  • the alloy 2 according to the present invention allows to obtain weights having only a primary dendritic recess while the counterweight prepared with the anterior mischmetal has a large recess or recess.
  • the lanthanum / Rare Earth ratio in mischmetal is equal to 0.25. This ratio according to the present invention must be, as mentioned above, at least equal to 2, preferably at least equal to 10 and more preferably at least equal to 100.
  • a cast iron is obtained having the composition mentioned in Table III with the physical characteristics also mentioned in Table III.
  • lanthanum can solve the problems associated with the deoxidation of steel.
  • a pocket deoxidation is carried out by adding 27 kg of a silico-lanthanum alloy comprising 45% of Si, 0.5% of La, the remainder being iron, an addition of about 0.20% of the alloy lanthanum which corresponds to an addition of about 10- 3% lanthanum or about 10 ppm.
  • a sample of steel is taken from the pocket after the deoxidation with the lanthanum inoculating alloy of the present invention and a steel is obtained having the following composition:
  • the lanthanum according to the present invention in alloy with other metals, including with Rare Earths in so far as the above-mentioned lanthanum / Rare Earths ratio is respected gives the possibility, in the course of the deoxidation kinetics, desulfurization, denitriding and dehydration, to provide and obtain the number of inclusions of the desired size and composition for the steel applications that it is desired to produce, which constitutes a particularly remarkable industrial result.
  • lanthanum is found in the ferrous alloy in the form of compounds such as oxides, and / or sulfides, and / or nitrides, and / or hydrides, and / or carbides forming non-annoying inclusions in ferrous alloys.
  • lanthanum is incorporated into the ferrous alloy, during its preparation in the form of an inoculating alloy having the following composition (percentage by weight):
  • the steels prepared by the process of the present invention can be in particular structural steels, special steels, stainless steels, molding or rolling but are not limited to these.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Mechanical Engineering (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Treatment Of Steel In Its Molten State (AREA)
  • Hard Magnetic Materials (AREA)
  • Continuous Casting (AREA)
EP79400224A 1978-04-06 1979-04-05 Procédé de préparation d'alliages ferreux permettant d'améliorer notamment leurs propriétés mécaniques grâce à l'emploi de lanthane et alliages ferreux obtenus par ce procédé Expired EP0004819B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7810254 1978-04-06
FR7810254A FR2421948A1 (fr) 1978-04-06 1978-04-06 Procede de preparation d'alliages ferreux sensiblement exempts de cerium, permettant d'ameliorer notamment leurs proprietes mecaniques grace a l'emploi de lanthane, et alliages ferreux obtenus par ce procede

Publications (2)

Publication Number Publication Date
EP0004819A1 EP0004819A1 (fr) 1979-10-17
EP0004819B1 true EP0004819B1 (fr) 1983-06-08

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Family Applications (1)

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EP79400224A Expired EP0004819B1 (fr) 1978-04-06 1979-04-05 Procédé de préparation d'alliages ferreux permettant d'améliorer notamment leurs propriétés mécaniques grâce à l'emploi de lanthane et alliages ferreux obtenus par ce procédé

Country Status (19)

Country Link
US (2) US4290805A (enrdf_load_stackoverflow)
EP (1) EP0004819B1 (enrdf_load_stackoverflow)
JP (1) JPS54136517A (enrdf_load_stackoverflow)
AR (1) AR222327A1 (enrdf_load_stackoverflow)
AT (1) ATA245979A (enrdf_load_stackoverflow)
AU (1) AU528318B2 (enrdf_load_stackoverflow)
BR (1) BR7902098A (enrdf_load_stackoverflow)
CA (1) CA1155688A (enrdf_load_stackoverflow)
DD (1) DD143632A5 (enrdf_load_stackoverflow)
DE (1) DE2965601D1 (enrdf_load_stackoverflow)
ES (1) ES479405A1 (enrdf_load_stackoverflow)
FI (1) FI68665C (enrdf_load_stackoverflow)
FR (1) FR2421948A1 (enrdf_load_stackoverflow)
IN (1) IN151970B (enrdf_load_stackoverflow)
MX (1) MX6617E (enrdf_load_stackoverflow)
NO (1) NO152452C (enrdf_load_stackoverflow)
PL (1) PL214742A1 (enrdf_load_stackoverflow)
YU (1) YU82579A (enrdf_load_stackoverflow)
ZA (1) ZA791569B (enrdf_load_stackoverflow)

Families Citing this family (21)

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US4714598A (en) * 1979-04-19 1987-12-22 Kay D Alan R Methods of desulfurizing gases
US4604268A (en) * 1979-04-19 1986-08-05 Kay Alan R Methods of desulfurizing gases
US4507149A (en) * 1979-04-19 1985-03-26 Union Oil Company Of California Desulfurization of fluid materials
US4885145A (en) * 1979-04-19 1989-12-05 Kay D Alan R Method for providing oxygen ion vacancies in lanthanide oxides
US4826664A (en) * 1980-07-31 1989-05-02 Kay D Alan R Methods of desulfurizing gases
US4857280A (en) * 1979-04-19 1989-08-15 Kay D Alan R Method for the regeneration of sulfided cerium oxide back to a form that is again capable of removing sulfur from fluid materials
US5326737A (en) * 1980-07-31 1994-07-05 Gas Desulfurization Corporation Cerium oxide solutions for the desulfurization of gases
FR2511044A1 (fr) * 1981-08-04 1983-02-11 Nobel Bozel Ferro-alliage pour le traitement d'inoculation des fontes a graphite spheroidal
US4409043A (en) * 1981-10-23 1983-10-11 The United States Of America As Represented By The Secretary Of The Navy Amorphous transition metal-lanthanide alloys
US4374665A (en) * 1981-10-23 1983-02-22 The United States Of America As Represented By The Secretary Of The Navy Magnetostrictive devices
SE466059B (sv) * 1990-02-26 1991-12-09 Sintercast Ltd Foerfarande foer kontroll och justering av primaer kaernbildningsfoermaaga hos jaernsmaeltor
JP2634707B2 (ja) * 1991-04-04 1997-07-30 日立金属株式会社 球状黒鉛鋳鉄の製造方法
IT1286045B1 (it) * 1996-10-25 1998-07-07 Lucchini Centro Ricerche E Svi Acciaio a grano austenitico fine risolforato migliorato e relativo procedimento per ottenerlo
FR2838134B1 (fr) * 2002-04-03 2005-02-25 Pechiney Electrometallurgie Pion inoculant anti microretassures pour traitement des fontes de moulage
FR2839082B1 (fr) * 2002-04-29 2004-06-04 Pechiney Electrometallurgie Alliage inoculant anti microretassure pour traitement des fontes de moulage
NO20024185D0 (no) * 2002-09-03 2002-09-03 Elkem Materials Fremgangsmåte for å fremstille duktilt jern
FR2855186B1 (fr) * 2003-05-20 2005-06-24 Pechiney Electrometallurgie Produits inoculants contenant du bismuth et des terres rares
JP4974591B2 (ja) * 2005-12-07 2012-07-11 旭テック株式会社 黒鉛球状化剤およびこれを用いた球状黒鉛鋳鉄の製造方法
FR3006695A1 (fr) 2013-06-10 2014-12-12 Mourad Toumi Procede et dispositif de traitement d'un metal ou d'un alliage metallique en fusion par une substance additive
PL232535B1 (pl) 2015-01-22 2019-06-28 Artur Gibas Igła do biopsji stercza
RU2628717C1 (ru) * 2016-09-23 2017-08-21 Юлия Алексеевна Щепочкина Сплав для легирования чугуна

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DE1190198B (de) * 1961-09-25 1965-04-01 Knapsack Ag Verfahren zur Herstellung von Silizium-Magnesium-Eisen-Vorlegierungen
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Also Published As

Publication number Publication date
ZA791569B (en) 1980-04-30
FI68665C (fi) 1985-10-10
NO152452B (no) 1985-06-24
EP0004819A1 (fr) 1979-10-17
FI791106A7 (fi) 1979-10-07
NO791147L (no) 1979-10-09
CA1155688A (en) 1983-10-25
NO152452C (no) 1985-10-02
US4290805A (en) 1981-09-22
AU528318B2 (en) 1983-04-21
AR222327A1 (es) 1981-05-15
JPS54136517A (en) 1979-10-23
FI68665B (fi) 1985-06-28
DD143632A5 (de) 1980-09-03
FR2421948B1 (enrdf_load_stackoverflow) 1981-03-06
FR2421948A1 (fr) 1979-11-02
ATA245979A (de) 1988-01-15
YU82579A (en) 1983-10-31
MX6617E (es) 1985-08-23
IN151970B (enrdf_load_stackoverflow) 1983-09-17
US4414027A (en) 1983-11-08
DE2965601D1 (en) 1983-07-14
AU4603179A (en) 1979-10-11
PL214742A1 (enrdf_load_stackoverflow) 1980-01-02
BR7902098A (pt) 1979-11-27
ES479405A1 (es) 1980-06-16

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