US20150284830A1 - Inoculant alloy for thick cast-iron parts - Google Patents

Inoculant alloy for thick cast-iron parts Download PDF

Info

Publication number
US20150284830A1
US20150284830A1 US14/441,761 US201314441761A US2015284830A1 US 20150284830 A1 US20150284830 A1 US 20150284830A1 US 201314441761 A US201314441761 A US 201314441761A US 2015284830 A1 US2015284830 A1 US 2015284830A1
Authority
US
United States
Prior art keywords
inoculant
iron
cast
antimony
alloy
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.)
Abandoned
Application number
US14/441,761
Inventor
Aurelie Fay
Mourad Toumi
Thomas Margaria
Daniel Berruex
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.)
Ferroglobe France SAS
Original Assignee
Ferropem SAS
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Ferropem SAS filed Critical Ferropem SAS
Assigned to FERROPEM reassignment FERROPEM ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: BERRUEX, Daniel, MARGARIA, THOMAS, FAY, AURELIE, TOUMI, Mourad
Publication of US20150284830A1 publication Critical patent/US20150284830A1/en
Abandoned legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C37/00Cast-iron alloys
    • C22C37/10Cast-iron alloys containing aluminium or silicon
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D19/00Casting in, on, or around objects which form part of the product
    • B22D19/14Casting in, on, or around objects which form part of the product the objects being filamentary or particulate in form
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D27/00Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
    • B22D27/20Measures not previously mentioned for influencing the grain structure or texture; Selection of compositions therefor
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00Refining of pig-iron; Cast iron
    • C21C1/08Manufacture of cast-iron
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00Refining of pig-iron; Cast iron
    • C21C1/10Making spheroidal graphite cast-iron
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21CPROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C1/00Refining of pig-iron; Cast iron
    • C21C1/10Making spheroidal graphite cast-iron
    • C21C1/105Nodularising additive agents
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C28/00Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C29/00Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
    • C22C29/18Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on silicides
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/02Making ferrous alloys by powder metallurgy
    • C22C33/0242Making ferrous alloys by powder metallurgy using the impregnating technique
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/02Making ferrous alloys by powder metallurgy
    • C22C33/0257Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
    • C22C33/0264Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements the maximum content of each alloying element not exceeding 5%
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/02Making ferrous alloys by powder metallurgy
    • C22C33/0257Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
    • C22C33/0278Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements with at least one alloying element having a minimum content above 5%
    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C33/00Making ferrous alloys
    • C22C33/08Making cast-iron alloys

Definitions

  • the present invention relates to an inoculant alloy for treating cast-iron.
  • Cast-iron is a well-known iron-carbon alloy widely used for manufacturing mechanical parts. Cast-iron is obtained by mixing the constituents of the alloy in the liquid state at a temperature comprised between 1320 and 1450° C. before casting in a mold and by cooling the obtained alloy.
  • carbon When cooling, carbon may adopt several physicochemical structures depending on several parameters.
  • White cast-iron has the characteristic of being hard and brittle, which is not desirable for some applications.
  • gray cast-iron If carbon appears in the form of graphite, the resulting cast-iron is called gray cast-iron. Gray cast-iron is softer and may be worked.
  • the liquid cast-iron undergoes an inoculation treatment aiming to introduce in the cast-iron graphitizing components or graphitization supports commonly called germs which will promote, when the cast-iron is cooling in the mold, the apparition of graphite rather than iron carbide.
  • the components of an inoculant hence consist of elements which promote the formation of graphite and the decomposition of iron carbide during the solidification of the cast-iron.
  • examples may include carbon, silicon, calcium, aluminum.
  • an inoculant may be designed so as to fulfill other functions and comprise to this end other components having a particular effect.
  • the cast-iron may also undergo prior or subsequent additional treatments.
  • the formed graphite is spheroidal, vermicular or lamellar.
  • Either graphitic form may be obtained preferably by a particular treatment of the cast-iron by means of specific components.
  • spheroidal graphite may be promoted by a treatment called nodularizer treatment mainly aiming to provide the cast-iron with an enough quantity of magnesium so that graphite can grow so as to form round particles (spheroids or nodules).
  • nodularizer components are generally added in the form of a specific alloy (nodularizer alloy) prior to the inoculant treatment of the cast-iron during a particular treatment.
  • the nodularizer alloy allows essentially to influence the shape of the graphite nodules, whereas the inoculant product aims to increase the number of these nodules and homogenize the graphitic structures.
  • These treatments may be performed at once or in several times and at different moments during manufacturing the cast-iron.
  • inoculants are conventionally manufactured from a ferrosilicon alloy such as FeSi 45 , FeSi 65 or FeSi 75 while adjusting the chemistry according to the aimed composition of the inoculant. It may also consist of mixtures of several alloys.
  • the inoculation efficiency of the cast-iron part also depends on its thickness (or on the solidification rate).
  • cooling will be slower (2 to 4 hours) and will promote the formation of graphite.
  • parts having areas with different thicknesses may have physicochemical structures which differ from one area to another, which is not desirable.
  • the formation of degenerated graphite and/or chunky graphite may reduce the mechanical properties of the cast-iron.
  • the smelter generally proceeds to the addition of pure Antimony in the liquid metal.
  • the addition of pure Antimony in the liquid metal raises accuracy problems because the rate of introduction is very low (in the order of 10 to 30 g per tonne of liquid cast-iron).
  • the addition efficiency of pure Antimony is comprised between 50 and 80% and the effective introduced quantity is hence difficult to control.
  • degraded graphite may be formed in the structure.
  • the smelter should further associate Rare Earths (abbreviated as RE) in order to achieve a maximum improvement of the form of the graphite.
  • RE Rare Earths
  • the part will have a spiky type graphite defect.
  • the graphite defect will rather be of the chunky type, which essentially happens when the used raw materials are relatively pure.
  • the introduction of pure antimony in the liquid cast-iron causes its vaporization and thus results in a strong gassing. It has been measured that, with the addition of pure antimony, the threshold of release of antimony in the working environment is higher than 0.5 mg/m 3 , which is the exposition limit value (ELV set by the regulations). Hence, the operators must work with a respirator for protection from N95-type particles or higher.
  • such an inoculant for thin parts comprises in particular a ferrosilicon-based inoculant alloy and comprising between 0.005 and 3% by weight of Rare Earths, in particular Lanthanum, as well as between 0.005 and 3% by weight of bismuth, lead or antimony with a Rare Earths/(Bismuth+Lead+Antimony) ratio comprised between 0.9 and 2.2; bismuth being particularly preferred, the descriptions of these documents covering only but bismuth.
  • the document WO2006/068487A1 describes an inoculant comprising a phase-modifying component (inoculant function) associated with an agent for modifying the structure of the graphite which may consist of antimony.
  • this structure-modifying agent is used in mixture with the inoculant compound (ferrosilicon) and not in an allied form.
  • antimony is clearly referred to as being a perlite promoter, which phase is not desirable in general, as above-mentioned.
  • the used quantity of antimony is comprised between 3 and 15%, which corresponds to a significant quantity probably at the origin of the formed perlite proportion.
  • JP2200718A describes an inoculant which consists of a mixture of ferrosilicon, antimony, calcium silicide and rare earths. Antimony is not used in an allied form.
  • JP57067146A describes a ferrosilicon-based alloy comprising between 5 and 50% by weight of antimony and up to 10% of rare earths. Besides the high proportion of antimony, this alloy is used as a perlite inhibitor, and not as an inoculant.
  • the present invention aims an inoculant alloy for treating thick ferrosilicon-based cast-iron parts, containing between 0.005 and 3% by weight of rare earths, characterized in that it also contains between 0.2 and 2% by weight of antimony.
  • antimony when allied to rare earths in a ferrosilicon-based alloy according to the claimed proportions, would allow an effective inoculation, and with the spheroids stabilized, of thick parts without the above-mentioned drawbacks of pure antimony.
  • the introduction of antimony in the form of an alloy allows achieving a high efficiency of use of antimony, in the order of 97 to 99%.
  • the effective introduced quantity is known much more precisely.
  • an alloy according to the invention allows limiting the gassing of antimony between 0.1 and 0.2 mg/m 3 and the use of a respirator mask is no longer necessary.
  • the antimony/rare earths association significantly lengthens the antimony decay time. Hence, the produced effect lasts longer in the complete foundry process. It will be noted that the antimony decay time is even longer than the bismuth decay time in the inoculant alloys for thin parts.
  • the alloy according to the present application upon ladle or furnace addition, may thereby allow replacing and even suppressing an additional jet or late inoculation.
  • the alloy according to the present application also allows particularly limiting greatly and even avoiding the formation of chunky or spiky type graphite defects, but also improving the form of graphite by ensuring a nodularity greater than 95% while bringing the spheroids closer to the perfect sphere.
  • the alloy according to the present application allows thus ensuring a homogeneous ferrite/perlite matrix across the different thicknesses of the manufactured part, which improves in particular the conditions of a subsequent machining of the part.
  • the ratio Antimony to Rare Earths will be higher than 1.4, preferably higher than 1.6, and lower than 2.5, preferably lower than 2.
  • the inoculant alloy also comprises magnesium. It will then be a nodularizer with an additional inoculant effect.
  • antimony allows achieving a better efficiency of the magnesium introduced in the cast-iron.
  • the inoculant alloy does not contain magnesium.
  • the ratio rare earths to antimony is comprised between 0.9 and 2.2.
  • the proportion by weight of Antimony is higher than 0.3%, preferably higher than 0.5%, still preferably higher than 0.8%.
  • the proportion by weight of antimony is lower than 1.5%, preferably lower than 1.3%.
  • the rare earths comprise Lanthanum, preferably only but Lanthanum.
  • the proportion by weight of rare earths is higher than 0.2%, preferably higher than 0.3%.
  • the proportion by weight of rare earths is lower than 1.2%, preferably lower than 1%.
  • the present invention also relates to the use of the inoculant according to the invention.
  • said inoculant is introduced in the form of a powder.
  • said inoculant is introduced in the form of a solid insert placed in a casting mold.
  • the use of the inoculant according to the invention aims to manufacture cast-iron parts having portions with thicknesses larger than 6 mm, preferably portions with thicknesses larger than 20 mm, and still more preferably portions with thicknesses larger than 50 mm.
  • the inoculant according to the invention will be typically used in the context of an inoculation of a cast-iron bath. It may also be used for pre-conditioning said cast-iron as well as a nodularizer, if appropriate.
  • composition of an inoculant alloy according to the invention may for example comprise:
  • Inoculant alloy-composition 1 Quantity Element (% by weight) Si 45-80 Ca 0.5-4 Al 0.5-3 Sb 0.2-2 Rare Earths 0.2-3 (including Lanthanum) Iron Balance
  • the inoculant may also comprise additional elements which bring particular effects depending on the required properties. More particularly, this may be the case in the context of an iron-cast pre-conditioning treatment.
  • the inoculant alloy thus may have the following composition:
  • Inoculant alloy-composition 2 Quantity Element (% by weight) Si 45-80 Ca 0.5-8 Al 0.5-3 Sb 0.2-2 Rare Earths 0.2-3 (including Lanthanum) Ba 2-15 Mn 2-6 Zr 2-6 Iron Balance
  • An inoculation treatment will typically consist in adding from 0.05 (preferably at least 0.1%) to 0.8% by weight of the inoculant to the cast-iron bath, in particular under the following conditions given as examples:
  • the grain size distribution of the inoculant according to the invention may be adapted depending on its methods of addition.
  • Examples may include:
  • the inoculant alloy may also be successfully added as an inoculant before filling the casting mold or during a ladle or late inoculation, after having adjusted the chemistry of the alloy (in particular Ba between 1.5 and 5% by weight and Ca between 0.5 and 2% by weight).
  • composition of the alloy will also comprise magnesium.
  • composition of such a nodularizer alloy with an inoculant function may be as follows:
  • Nodularizer alloy with inoculant effect-composition 3 Quantity Element (% by weight) Si 30-60 Ca 0.2-5 Al 0.2-3 Sb 0.1-2 Rare Earths 0.1-3 (including Lanthanum) Mg 3-12 Iron Balance
  • the grain size distribution of the nodularizer (in particular with an inoculant function) according to the invention will be adapted depending on the size of the treatment ladles. For example, for ladles with 100 to 500 kg of cast-iron, preference will be given to a grain size distribution comprised between about 0.4 and about 2 mm, and even up to 7 mm. For ladles with 500 to 1000 kg of cast-iron, preference will be given to a grain size distribution comprised between about 2 and about 7 mm, or between about 10 and about 30 mm. For ladles with more than 1000 kg of cast-iron, preference will be given to a grain size distribution comprised between about 10 and about 30 mm.
  • liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 30 g of antimony per tonne of liquid cast-iron.
  • the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising a third of a FeSiMg alloy comprising 2% of rare earths and two thirds of a FeSiMg alloy free of rare earths.
  • the cast-iron has undergone an inoculation treatment by addition, in the casting basin, of 0.1% by weight of a FeSiMnZr alloy and 0.1% of a FeSiAl alloy, the inoculant alloys being added in the form of an inoculant insert in the mold.
  • the step of addition of pure antimony has been suppressed and the nodularizer treatment has been simplified by using only but a FeSiMg nodularizer alloy which does not contain rare earths.
  • the foundry A treated with an inoculant according to the present application, has shown an increase of the tensile elongation on test samples for a EN-GJS-400-15 grade.
  • liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 20 g of antimony per tonne of liquid cast-iron.
  • the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 1% by weight of rare earths and introduced in the cast iron in the form of a cored wire.
  • the cast-iron has undergone an inoculation treatment by addition, in the casting basin, of 0.15% by weight of a FeSiBiRE alloy.
  • the step of addition of pure antimony has been suppressed and the nodularizer treatment has been simplified by using only but a nodularizer alloy FeSiMg which does not contain rare earths (also introduced in the form of a cored wire).
  • the cast-iron B2 has achieved results in compliance with the requirements.
  • liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 25 g of antimony per tonne of liquid cast-iron.
  • the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 6.7% by weight of magnesium as well as 1.2% of calcium and 0.98% of rare earths.
  • the cast-iron has undergone a late inoculation treatment by addition of 0.12% by weight of a FeSiMnZrBa alloy having a grain size distribution comprised between 0.2 and 5 mm.
  • a nodularizer alloy with an inoculant function according to the above-mentioned composition 3 has been used.
  • the nodularizer treatment has been performed by means of a FeSiMg type alloy according to the composition 3 of the present application and comprising 6.4% by weight of magnesium as well as 1.3% of calcium, 0.6% of antimony and 1.2% of rare earths.
  • a complementary inoculation has been performed according to a late inoculation method with 0.09% of a FeSiAlCa alloy and 0.009% of a FeSiMnZrBa alloy.
  • liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 30 g of antimony per tonne of liquid cast-iron.
  • the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 9.1% by weight of magnesium as well as 1.4% of calcium and 1.1% of rare earths.
  • the cast-iron has undergone an inoculation treatment by addition of a 10 kg insert per tonne of cast-iron of a FeSiMnZr inoculant alloy.
  • the nodularizer treatment has been performed by means of a same alloy as the reference, namely by using a FeSiMg type nodularizer alloy comprising 9.1% by weight of magnesium as well as 1.4% of calcium and 1.1% of rare earths.
  • the cast-iron D allows preparing a cast-iron EN-GJS-400-18-LT grade, used in particular in the wind power field.
  • the use of the inoculant according to the application has allowed significantly increasing the impact resistance.
  • the liquid cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 9.1% by weight of Magnesium as well as 0.8% of Bismuth and 0.7% of rare earths.
  • the cast-iron has undergone an inoculation treatment according to a late inoculation method by addition of 0.18% of a FeSiMnZr alloy having a grain size distribution comprised between 0.2 and 5 mm.
  • a nodularizer alloy according to the above-mentioned composition 3 has been used.
  • the used alloy is a FeSiMg type alloy comprising 9.1% of magnesium as well as 0.75% of antimony and 0.5% of rare earths.
  • the cast-iron has undergone an additional inoculation treatment according to a late inoculation method by addition of 0.17% of a FeSiMnZr alloy having a grain size distribution comprised between 0.2 and 5 mm.
  • the foundry reference (F1) and the test (F2) using an inoculant alloy according to the application have been realized in accordance with the example 4 and the foundry D by inoculating massive parts.
  • the foundry F2 has allowed for a significant economy by reducing by 31.5% the doses of antimony to be added.
  • the foundry reference (G1) and the test (G2) using an inoculant alloy according to the application have been realized in accordance with the example 4 and the foundry D by inoculating massive parts.
  • the antimony release is significantly limited and much lower than the regulatory threshold 0.5 mg/m 3 .
  • the work conditions are thereby improved.
  • liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 15 g of antimony per tonne of liquid cast-iron.
  • the cast-iron has undergone a nodularizer treatment by means of nodularizer cored wire (13 mm diameter, 32% of Mg, 1.2% of RE, 230 g/m of powder).
  • the cast-iron has undergone a late inoculation treatment by addition, to the casting jet, of 0.15% by weight of a FeSiMnZr alloy.
  • the cast-iron H2 Upon the impact resistance results, the cast-iron H2 has achieved results in compliance with the requirements.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Manufacturing & Machinery (AREA)
  • Refinement Of Pig-Iron, Manufacture Of Cast Iron, And Steel Manufacture Other Than In Revolving Furnaces (AREA)
  • Hard Magnetic Materials (AREA)

Abstract

The present invention relates to an inoculant alloy for treating thick ferrosilicon-based cast-iron parts, containing between 0.005 and 3% by weight of Rare Earths, characterized in that it also contains between 0.2 and 2% by weight of Antimony.

Description

  • The present invention relates to an inoculant alloy for treating cast-iron.
  • Cast-iron is a well-known iron-carbon alloy widely used for manufacturing mechanical parts. Cast-iron is obtained by mixing the constituents of the alloy in the liquid state at a temperature comprised between 1320 and 1450° C. before casting in a mold and by cooling the obtained alloy.
  • When cooling, carbon may adopt several physicochemical structures depending on several parameters.
  • When carbon is associated with iron and forms iron carbide Fe3C (also called cementite), the resulting cast-iron is called white cast-iron. White cast-iron has the characteristic of being hard and brittle, which is not desirable for some applications.
  • If carbon appears in the form of graphite, the resulting cast-iron is called gray cast-iron. Gray cast-iron is softer and may be worked.
  • In order to obtain cast-iron parts having good mechanical properties, it is hence necessary to obtain a structure of the cast-iron comprising the maximum of carbon in the form of graphite and limit as much as possible the formation of these iron carbides which harden and embrittle the alloy.
  • In the absence of any particular inoculation treatment, carbon tends however to be associated with iron so as to form iron carbide. Hence, it is necessary to treat the cast-iron in the liquid state so as to modify the association parameters of carbon and obtain the desired structure.
  • To this end, the liquid cast-iron undergoes an inoculation treatment aiming to introduce in the cast-iron graphitizing components or graphitization supports commonly called germs which will promote, when the cast-iron is cooling in the mold, the apparition of graphite rather than iron carbide.
  • In general, the components of an inoculant hence consist of elements which promote the formation of graphite and the decomposition of iron carbide during the solidification of the cast-iron. Examples may include carbon, silicon, calcium, aluminum.
  • Of course, an inoculant may be designed so as to fulfill other functions and comprise to this end other components having a particular effect. The cast-iron may also undergo prior or subsequent additional treatments.
  • Thus, depending on the required properties, it may be desired in particular that the formed graphite is spheroidal, vermicular or lamellar.
  • Either graphitic form may be obtained preferably by a particular treatment of the cast-iron by means of specific components.
  • Thus, for example the formation of spheroidal graphite may be promoted by a treatment called nodularizer treatment mainly aiming to provide the cast-iron with an enough quantity of magnesium so that graphite can grow so as to form round particles (spheroids or nodules).
  • These nodularizer components are generally added in the form of a specific alloy (nodularizer alloy) prior to the inoculant treatment of the cast-iron during a particular treatment.
  • Thus, the nodularizer alloy allows essentially to influence the shape of the graphite nodules, whereas the inoculant product aims to increase the number of these nodules and homogenize the graphitic structures.
  • Mention may also be made of the addition of desulfurizing products, or products allowing specifically treating some defects of the cast-iron depending on the initial composition of the liquid cast-iron bath, such as micro-shrinkages and pinholes, likely to appear during cooling.
  • These treatments may be performed at once or in several times and at different moments during manufacturing the cast-iron.
  • Most inoculants are conventionally manufactured from a ferrosilicon alloy such as FeSi45, FeSi65 or FeSi75 while adjusting the chemistry according to the aimed composition of the inoculant. It may also consist of mixtures of several alloys.
  • It should be noted that the inoculation efficiency of the cast-iron part also depends on its thickness (or on the solidification rate).
  • In the areas with small thicknesses, which cool more quickly, a higher risk of carbides formation will be noted.
  • Conversely, in the areas with larger thicknesses, cooling will be slower (2 to 4 hours) and will promote the formation of graphite.
  • As a result, parts having areas with different thicknesses may have physicochemical structures which differ from one area to another, which is not desirable.
  • Furthermore, controlling germination in the areas with large thickness remains difficult and may result in obtaining a non-uniform structure.
  • For parts with large thicknesses, when the inoculation method is not controlled, the formation of degenerated graphite and/or
    Figure US20150284830A1-20151008-P00001
    chunky
    Figure US20150284830A1-20151008-P00002
    graphite may reduce the mechanical properties of the cast-iron. In order to solve these defects, the smelter generally proceeds to the addition of pure Antimony in the liquid metal.
  • The addition of pure Antimony in the liquid metal raises accuracy problems because the rate of introduction is very low (in the order of 10 to 30 g per tonne of liquid cast-iron). The addition efficiency of pure Antimony is comprised between 50 and 80% and the effective introduced quantity is hence difficult to control.
  • If the quantity is not enough, degraded graphite may be formed in the structure.
  • Conversely, if the introduced quantity exceeds the target, antimony will tend to strongly increase the perlite proportion, which phase is not desirable in ferritic structures.
  • In the case of addition of pure antimony, the smelter should further associate Rare Earths (abbreviated as RE) in order to achieve a maximum improvement of the form of the graphite. Similarly, if the quantity of Rare Earths is not enough, the part will have a
    Figure US20150284830A1-20151008-P00001
    spiky
    Figure US20150284830A1-20151008-P00002
    type graphite defect. Conversely, if the quantity of Rare Earths is highly dosed, the graphite defect will rather be of the
    Figure US20150284830A1-20151008-P00001
    chunky
    Figure US20150284830A1-20151008-P00002
    type, which essentially happens when the used raw materials are relatively pure.
  • These
    Figure US20150284830A1-20151008-P00001
    spiky
    Figure US20150284830A1-20151008-P00002
    or
    Figure US20150284830A1-20151008-P00001
    chunky
    Figure US20150284830A1-20151008-P00002
    type graphite defects deteriorate the mechanical properties of cast-iron, and in particular the tensile strength and the impact resistance of the formed part.
  • Furthermore, the introduction of pure antimony in the liquid cast-iron causes its vaporization and thus results in a strong gassing. It has been measured that, with the addition of pure antimony, the threshold of release of antimony in the working environment is higher than 0.5 mg/m3, which is the exposition limit value (ELV set by the regulations). Hence, the operators must work with a respirator for protection from N95-type particles or higher.
  • The treatment of parts with small thicknesses has already been considered for developments of specific inoculants. The documents FR2511044A1, FR2855186A1 and EP0816522A1 describe such an inoculant for thin parts.
  • According to these documents, such an inoculant for thin parts comprises in particular a ferrosilicon-based inoculant alloy and comprising between 0.005 and 3% by weight of Rare Earths, in particular Lanthanum, as well as between 0.005 and 3% by weight of bismuth, lead or antimony with a Rare Earths/(Bismuth+Lead+Antimony) ratio comprised between 0.9 and 2.2; bismuth being particularly preferred, the descriptions of these documents covering only but bismuth.
  • It should be noted that these documents disclose the use of antimony only in a general manner and that they contain neither specific example nor particular value related to this element.
  • Among the other documents that mention the use of antimony, the following documents may be cited.
  • The document WO2006/068487A1 describes an inoculant comprising a phase-modifying component (inoculant function) associated with an agent for modifying the structure of the graphite which may consist of antimony. It should be noted that this structure-modifying agent is used in mixture with the inoculant compound (ferrosilicon) and not in an allied form. Furthermore, antimony is clearly referred to as being a perlite promoter, which phase is not desirable in general, as above-mentioned. The used quantity of antimony is comprised between 3 and 15%, which corresponds to a significant quantity probably at the origin of the formed perlite proportion.
  • The document JP2200718A describes an inoculant which consists of a mixture of ferrosilicon, antimony, calcium silicide and rare earths. Antimony is not used in an allied form.
  • The document JP57067146A describes a ferrosilicon-based alloy comprising between 5 and 50% by weight of antimony and up to 10% of rare earths. Besides the high proportion of antimony, this alloy is used as a perlite inhibitor, and not as an inoculant.
  • There are also several articles and documents dealing with a nodularizer function (the graphite form) of antimony, which is not the fundamental purpose and which does not resolve the inoculation problem (number and quality of the nodules).
  • Furthermore, it consists most often of a use of antimony in a mixed and non-allied form.
  • Hence, there is a need for an inoculant alloy which allows improving the treatment of thick parts.
  • To do so, the present invention aims an inoculant alloy for treating thick ferrosilicon-based cast-iron parts, containing between 0.005 and 3% by weight of rare earths, characterized in that it also contains between 0.2 and 2% by weight of antimony.
  • Thus, it has indeed been unexpectedly observed that antimony, when allied to rare earths in a ferrosilicon-based alloy according to the claimed proportions, would allow an effective inoculation, and with the spheroids stabilized, of thick parts without the above-mentioned drawbacks of pure antimony.
  • In particular, the introduction of antimony in the form of an alloy allows achieving a high efficiency of use of antimony, in the order of 97 to 99%. Hence, the effective introduced quantity is known much more precisely.
  • Thus, the increase of efficiency allows for an economy of the products and simplifies the management of products additions, including rare earths.
  • Thanks to this increase of efficiency and to the simultaneous reduction of gaseous emissions in the atmosphere, the working conditions are also improved for the operators in charge of these additions.
  • The use of an alloy according to the invention allows limiting the gassing of antimony between 0.1 and 0.2 mg/m3 and the use of a respirator mask is no longer necessary.
  • It will also be noted that the antimony/rare earths association significantly lengthens the antimony decay time. Hence, the produced effect lasts longer in the complete foundry process. It will be noted that the antimony decay time is even longer than the bismuth decay time in the inoculant alloys for thin parts.
  • The alloy according to the present application, upon ladle or furnace addition, may thereby allow replacing and even suppressing an additional jet or late inoculation.
  • The alloy according to the present application also allows particularly limiting greatly and even avoiding the formation of
    Figure US20150284830A1-20151008-P00001
    chunky
    Figure US20150284830A1-20151008-P00002
    or
    Figure US20150284830A1-20151008-P00001
    spiky
    Figure US20150284830A1-20151008-P00002
    type graphite defects, but also improving the form of graphite by ensuring a nodularity greater than 95% while bringing the spheroids closer to the perfect sphere.
  • The alloy according to the present application allows thus ensuring a homogeneous ferrite/perlite matrix across the different thicknesses of the manufactured part, which improves in particular the conditions of a subsequent machining of the part.
  • Preferably, the ratio Antimony to Rare Earths will be higher than 1.4, preferably higher than 1.6, and lower than 2.5, preferably lower than 2.
  • According to a first variant, the inoculant alloy also comprises magnesium. It will then be a nodularizer with an additional inoculant effect.
  • Unexpectedly, it has in particular been observed that, unlike the already used bismuth, antimony allows achieving a better efficiency of the magnesium introduced in the cast-iron.
  • As regards bismuth, it is known that the latter accelerates the decantation of magnesium in cast-iron and that the latter thereby loses more active magnesium serving to the transformation of lamellar graphite into spheroidal graphite. The better assimilation of antimony in the form of a nodularizer according to the invention allows ensuring a good stability of the residual magnesium between 1350° C. and 1580° C.
  • According to a second variant, the inoculant alloy does not contain magnesium.
  • Preferably, the ratio rare earths to antimony is comprised between 0.9 and 2.2.
  • Preferably, the proportion by weight of Antimony is higher than 0.3%, preferably higher than 0.5%, still preferably higher than 0.8%.
  • Preferably, the proportion by weight of antimony is lower than 1.5%, preferably lower than 1.3%.
  • Advantageously, the rare earths comprise Lanthanum, preferably only but Lanthanum.
  • Preferably, the proportion by weight of rare earths is higher than 0.2%, preferably higher than 0.3%.
  • Preferably, the proportion by weight of rare earths is lower than 1.2%, preferably lower than 1%.
  • The present invention also relates to the use of the inoculant according to the invention.
  • According to a first variant of use, said inoculant is introduced in the form of a powder.
  • It should be noted in this regard that a drawback of the products described in the documents FR2511044A1 and EP0816522A1 has been a degradation of their grain size distribution over time during storage of the inoculant. The inoculant according to the invention has shown a high stability in the grain size distribution in some conditions.
  • According to a second variant, said inoculant is introduced in the form of a solid insert placed in a casting mold.
  • Preferably, the use of the inoculant according to the invention aims to manufacture cast-iron parts having portions with thicknesses larger than 6 mm, preferably portions with thicknesses larger than 20 mm, and still more preferably portions with thicknesses larger than 50 mm.
  • The present invention will be better understood in light of the description and examples which follow.
  • The inoculant according to the invention will be typically used in the context of an inoculation of a cast-iron bath. It may also be used for pre-conditioning said cast-iron as well as a nodularizer, if appropriate.
  • In the context of a typical use of an inoculant, the composition of an inoculant alloy according to the invention may for example comprise:
  • Inoculant alloy-composition 1
    Quantity
    Element (% by weight)
    Si  45-80
    Ca 0.5-4 
    Al 0.5-3 
    Sb 0.2-2 
    Rare Earths 0.2-3 
    (including Lanthanum)
    Iron Balance
  • Of course, the inoculant may also comprise additional elements which bring particular effects depending on the required properties. More particularly, this may be the case in the context of an iron-cast pre-conditioning treatment.
  • As example, the inoculant alloy thus may have the following composition:
  • Inoculant alloy-composition 2
    Quantity
    Element (% by weight)
    Si  45-80
    Ca 0.5-8 
    Al 0.5-3 
    Sb 0.2-2 
    Rare Earths 0.2-3 
    (including Lanthanum)
    Ba   2-15
    Mn  2-6
    Zr  2-6
    Iron Balance
  • An inoculation treatment will typically consist in adding from 0.05 (preferably at least 0.1%) to 0.8% by weight of the inoculant to the cast-iron bath, in particular under the following conditions given as examples:
      • at meltdown in the induction furnace
      • before a nodularizer treatment with magnesium, and more particularly 1 to 5 minutes before this treatment
      • as a cover of a subsequent
        Figure US20150284830A1-20151008-P00001
        Sandwich
        Figure US20150284830A1-20151008-P00002
        or
        Figure US20150284830A1-20151008-P00001
        Tunsich-cover
        Figure US20150284830A1-20151008-P00002
        type treatment.
      • in a casting furnace
      • during a transfer between two ladles (in particular transfer and casting)
      • the pre-conditioning inoculant may be added in particular in the form of a cored wire.
  • The grain size distribution of the inoculant according to the invention may be adapted depending on its methods of addition.
  • Examples may include:
      • addition in the induction furnace: grain size distribution up to about 40 mm.
      • addition between the induction furnace and the casting ladle: grain size distribution comprised between about 10 and about 30 mm.
      • addition in the casting basin: grain size distribution comprised between about 0.4 and about 2 mm.
      • addition before casting in the mold: grain size distribution comprised between about 0.2 and about 0.5 to 2 mm.
      • addition in the form of an inoculant insert placed in the casting mold: for example, 20 g, 40 g, 60 g, 80 g, 300 g, 800 g, 2 kg, 5 kg, 10 kg, 20 kg and 50 kg inserts.
  • The inoculant alloy may also be successfully added as an inoculant before filling the casting mold or during a ladle or late inoculation, after having adjusted the chemistry of the alloy (in particular Ba between 1.5 and 5% by weight and Ca between 0.5 and 2% by weight).
  • Depending on the metallurgical state of the cast-iron after treatment with the inoculant alloy according to the present application, it is possible to suppress the post-inoculation step. Indeed, maintaining the inoculation effect for prolonged time periods with the action of antimony allows significantly reducing the late inoculation treatments and even suppressing them. For example, when adding an inoculant containing the Bi/RE pair, the inoculation effect loses 30% during the first 4 minutes. Thus, late stage addition of an inoculant becomes mandatory in order to recover 100% of the inoculation effect to be achieved. This is not the case with an inoculant according to the present application.
  • In the context of a use as a nodularizer with an additional inoculant function, the composition of the alloy will also comprise magnesium. As example, the composition of such a nodularizer alloy with an inoculant function may be as follows:
  • Nodularizer alloy with inoculant
    effect-composition 3
    Quantity
    Element (% by weight)
    Si  30-60
    Ca 0.2-5 
    Al 0.2-3 
    Sb 0.1-2 
    Rare Earths 0.1-3 
    (including Lanthanum)
    Mg   3-12
    Iron Balance
  • The grain size distribution of the nodularizer (in particular with an inoculant function) according to the invention will be adapted depending on the size of the treatment ladles. For example, for ladles with 100 to 500 kg of cast-iron, preference will be given to a grain size distribution comprised between about 0.4 and about 2 mm, and even up to 7 mm. For ladles with 500 to 1000 kg of cast-iron, preference will be given to a grain size distribution comprised between about 2 and about 7 mm, or between about 10 and about 30 mm. For ladles with more than 1000 kg of cast-iron, preference will be given to a grain size distribution comprised between about 10 and about 30 mm.
  • Examples of use will now be described.
  • EXAMPLE 1 Foundry A—8 mm Thick Part
  • Foundry Reference (A1)
  • In accordance with the prior art, the liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 30 g of antimony per tonne of liquid cast-iron.
  • Afterwards, the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising a third of a FeSiMg alloy comprising 2% of rare earths and two thirds of a FeSiMg alloy free of rare earths.
  • Finally, the cast-iron has undergone an inoculation treatment by addition, in the casting basin, of 0.1% by weight of a FeSiMnZr alloy and 0.1% of a FeSiAl alloy, the inoculant alloys being added in the form of an inoculant insert in the mold.
  • Use of an Inoculant Alloy According to the Invention (A2)
  • An inoculant alloy according to the above-mentioned composition 2 and containing (by weight proportion): Si=65% Si, Ca=1.76% Ca, Al=1.23%, Sb=0.15%; RE=0.16%, Ba=7.9%; has been used in a proportion of 0.15% by weight of cast-iron.
  • The step of addition of pure antimony has been suppressed and the nodularizer treatment has been simplified by using only but a FeSiMg nodularizer alloy which does not contain rare earths.
  • Comparative Results
  • A1 A2
    (Reference) (Application)
    Graphite nodularity 95% 98%
    Matrix of the  8%  3%
    cast-iron (% perlite)
    Elongation 15% 18%
  • The foundry A, treated with an inoculant according to the present application, has shown an increase of the tensile elongation on test samples for a EN-GJS-400-15 grade.
  • EXAMPLE 2 Foundry B—200 mm Thick Part
  • Foundry Reference (B1)
  • In accordance with the prior art, the liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 20 g of antimony per tonne of liquid cast-iron.
  • Afterwards, the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 1% by weight of rare earths and introduced in the cast iron in the form of a cored wire.
  • Finally, the cast-iron has undergone an inoculation treatment by addition, in the casting basin, of 0.15% by weight of a FeSiBiRE alloy.
  • Use of an Inoculant Alloy According to the Application (B2)
  • An inoculant alloy according to the above-mentioned composition 2 and containing, as previously: Si=65% Si, Ca=1.76% Ca, Al=1.23%, Sb=0.15%, RE=0.16%, Ba=7.9%; has been used in a proportion of 0.15% by weight of cast-iron.
  • The step of addition of pure antimony has been suppressed and the nodularizer treatment has been simplified by using only but a nodularizer alloy FeSiMg which does not contain rare earths (also introduced in the form of a cored wire).
  • Comparative Results
  • B1 B2
    (Reference) (Application)
    Graphite nodularity 91% 97%
    Matrix of the cast-iron  4%  3%
    (% perlite)
    Figure US20150284830A1-20151008-P00003
    Chunky
    Figure US20150284830A1-20151008-P00004
     graphite defect
    15%  0%
    Resilience at −20° C. 7 J 12 J
  • As regards the impact resistance results, the cast-iron B2 has achieved results in compliance with the requirements.
  • EXAMPLE 3 Foundry C—Thin Parts (the Thickness is Smaller than 6 mm)
  • Foundry Reference (C1)
  • In accordance with the prior art, the liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 25 g of antimony per tonne of liquid cast-iron.
  • Afterwards, the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 6.7% by weight of magnesium as well as 1.2% of calcium and 0.98% of rare earths.
  • Finally, the cast-iron has undergone a late inoculation treatment by addition of 0.12% by weight of a FeSiMnZrBa alloy having a grain size distribution comprised between 0.2 and 5 mm.
  • Use of an Inoculant Alloy According to the Application with a Nodularizer Function (C2)
  • A nodularizer alloy with an inoculant function according to the above-mentioned composition 3 has been used.
  • As with the previous examples, the step of addition of pure antimony has been suppressed.
  • The nodularizer treatment has been performed by means of a FeSiMg type alloy according to the composition 3 of the present application and comprising 6.4% by weight of magnesium as well as 1.3% of calcium, 0.6% of antimony and 1.2% of rare earths.
  • A complementary inoculation has been performed according to a late inoculation method with 0.09% of a FeSiAlCa alloy and 0.009% of a FeSiMnZrBa alloy.
  • Comparative Results
  • C1 C2
    (Reference) (Application)
    Graphite nodularity 93%  98%
    Matrix of the 15% 4/5%
    cast-iron (% perlite)
    Figure US20150284830A1-20151008-P00005
     Chunky
    Figure US20150284830A1-20151008-P00006
     4%   0%
    graphite defect
  • When using a nodularizer according to the present application, it has been noted that
    Figure US20150284830A1-20151008-P00001
    Chunky
    Figure US20150284830A1-20151008-P00002
    graphite defects have disappeared in all controlled parts.
  • Thus, it has been possible to carry out the additional inoculation (late inoculation) by use of a more economical FeSiAlCa type inoculant.
  • EXAMPLE 4 Foundry D—Massive Parts
  • Foundry Reference (D1)
  • In accordance with the prior art, the liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 30 g of antimony per tonne of liquid cast-iron.
  • Afterwards, the cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 9.1% by weight of magnesium as well as 1.4% of calcium and 1.1% of rare earths.
  • Finally, the cast-iron has undergone an inoculation treatment by addition of a 10 kg insert per tonne of cast-iron of a FeSiMnZr inoculant alloy.
  • Use of an Inoculant Alloy According to the Application (D2)
  • An inoculant alloy according to the above-mentioned composition 2 and containing: Si=65% Si, Ca=1.76% Ca, Al=1.23%, Sb=0.15%, RE=0.16%, Ba=7.9%; has been used in the form of a 10 kg insert, in the same way as the reference.
  • As with the previous examples, the step of addition of pure antimony has been suppressed.
  • The nodularizer treatment has been performed by means of a same alloy as the reference, namely by using a FeSiMg type nodularizer alloy comprising 9.1% by weight of magnesium as well as 1.4% of calcium and 1.1% of rare earths.
  • Comparative Results
  • D1 D2
    (Reference) (Application)
    Graphite nodularity   92%  97%
    Matrix of the cast-iron (% perlite) 5/10% 0/5%
    Figure US20150284830A1-20151008-P00007
     Chunky
    Figure US20150284830A1-20151008-P00008
     graphite defect
      2%   0%
    Tensile strength 370 MPa 420 MPa
    Elongation   18%  22%
    Impact resistance at −20° C. 10 J 14 J
  • The cast-iron D allows preparing a cast-iron EN-GJS-400-18-LT grade, used in particular in the wind power field. The use of the inoculant according to the application has allowed significantly increasing the impact resistance.
  • EXAMPLE 5 Foundry E—Thin Parts Plus a Nodularizer Treatment
  • Foundry Reference (E1)
  • The liquid cast-iron has undergone a nodularizer treatment by means of a FeSiMg type nodularizer alloy comprising 9.1% by weight of Magnesium as well as 0.8% of Bismuth and 0.7% of rare earths.
  • Afterwards, the cast-iron has undergone an inoculation treatment according to a late inoculation method by addition of 0.18% of a FeSiMnZr alloy having a grain size distribution comprised between 0.2 and 5 mm.
  • Use of an Inoculant Alloy According to the Application with a Nodularizer Function (E2)
  • A nodularizer alloy according to the above-mentioned composition 3 has been used. The used alloy is a FeSiMg type alloy comprising 9.1% of magnesium as well as 0.75% of antimony and 0.5% of rare earths.
  • Afterwards, the cast-iron has undergone an additional inoculation treatment according to a late inoculation method by addition of 0.17% of a FeSiMnZr alloy having a grain size distribution comprised between 0.2 and 5 mm.
  • Comparative Results
  • E1 E2
    (Reference) (Application)
    Graphite nodularity 91% 95%
    Figure US20150284830A1-20151008-P00009
     Chunky
    Figure US20150284830A1-20151008-P00010
     2%  0%
    graphite defect
    Mg efficiency 54% 69%
  • As mentioned above, it has been observed that, by replacing bismuth with antimony, the efficiency of magnesium in the cast-iron E has increased.
  • EXAMPLE 6 Foundry D on Massive Parts
  • The foundry reference (F1) and the test (F2) using an inoculant alloy according to the application have been realized in accordance with the example 4 and the foundry D by inoculating massive parts.
  • Comparative Results
  • F1 F2
    (Reference) (Application)
    Sb efficiency 67% 98%
  • It has been observed that, thanks to the achieved high efficiency, it is possible to better control the added antimony quantity. The foundry F2 has allowed for a significant economy by reducing by 31.5% the doses of antimony to be added.
  • EXAMPLE 7 Foundry D on Massive Parts
  • The foundry reference (G1) and the test (G2) using an inoculant alloy according to the application have been realized in accordance with the example 4 and the foundry D by inoculating massive parts.
  • Comparative Results
  • G1 G2
    (Reference) (Application)
    Sb release in 8 hours 0.7 mg/m3 0.1 mg/m3
  • It has been observed that, thanks to the inoculant according to the present application, the antimony release is significantly limited and much lower than the regulatory threshold 0.5 mg/m3. The work conditions are thereby improved.
  • EXAMPLE 8 Foundry H—150 mm Thick Part
  • Foundry Reference (H1)
  • In accordance with the prior art, the liquid cast-iron has been treated by adding, in the induction furnace, pure antimony in a proportion of 15 g of antimony per tonne of liquid cast-iron.
  • Afterwards, the cast-iron has undergone a nodularizer treatment by means of nodularizer cored wire (13 mm diameter, 32% of Mg, 1.2% of RE, 230 g/m of powder).
  • Finally, the cast-iron has undergone a late inoculation treatment by addition, to the casting jet, of 0.15% by weight of a FeSiMnZr alloy.
  • Use of an Inoculant Alloy According to the Application (H2)
  • An inoculant alloy according to the above-mentioned composition 1 [containing Si=64% Si, Ca=1.64% Ca, Al=1.15%, Sb=0.5%, RE=0.3%] has been used in a proportion of 0.2% by weight of cast-iron.
  • The step of addition of pure antimony has been suppressed and the nodularizer treatment has been simplified by using only but a FeSiMg nodularizer alloy which does not contain rare earths (also introduced in the form of a cored wire).
  • Comparative Results
  • H1 H2
    (Reference) (Application)
    Graphite nodularity 87% 98%
    Matrix of the  3%  3%
    cast-iron (% perlite)
    Figure US20150284830A1-20151008-P00011
     Chunky
    Figure US20150284830A1-20151008-P00010
    19%  0%
    graphite defect
    Resilience at −20° C. 4 J 14 J
  • Upon the impact resistance results, the cast-iron H2 has achieved results in compliance with the requirements.
  • Although the invention has been described with particular embodiments, it goes without saying that it is not limited thereto and that it comprises all technical equivalents of the described means as well as their combinations if these are within the scope of the invention.

Claims (20)

1. An inoculant alloy for treating thick ferrosilicon-based cast-iron parts, containing between 0.005 and 3% by weight of Rare Earths, characterized in that it also contains between 0.2 and 2% by weight of Antimony.
2. The inoculant alloy according to claim 1, characterized in that it also comprises magnesium and constitutes a nodularizer alloy.
3. The inoculant alloy according to claim 1, characterized in that it does not contain magnesium.
4. The inoculant alloy according to claim 1, characterized in that the ratio of rare earths to antimony is comprised between 0.9 and 2.2.
5. The inoculant alloy according to claim 1, characterized in that the proportion by weight of antimony is higher than 0.3%.
6. The inoculant alloy according to claim 1, characterized in that the proportion by weight of antimony is lower than 1.5%.
7. The inoculant alloy according to claim 1, characterized in that the rare earths comprise Lanthanum.
8. The inoculant alloy according to claim 1, characterized in that the proportion by weight of rare earths is higher than 0.2%.
9. The inoculant alloy according to claim 1, characterized in that the proportion by weight of rare earths is lower than 1.2%.
10. A use of an inoculant according to claim 1, characterized in that said inoculant is introduced in the form of a powder.
11. The use of an inoculant according to claim 1, characterized in that said inoculant is introduced in the form of a solid insert placed in a casting mold.
12. The use of an inoculant according to claim 1 for manufacturing cast-iron parts having portions with thicknesses larger than 6 mm.
13. The inoculant alloy according to claim 5, characterized in that the proportion by weight of antimony is higher than 0.5%.
14. The inoculant alloy according to claim 5, characterized in that the proportion by weight of antimony is higher than 0.8%.
15. The inoculant alloy according to claim 6, characterized in that the proportion by weight of antimony is lower than 1.3%.
16. The inoculant alloy according to claim 7, characterized in that the rare earths comprise only lanthanum.
17. The inoculant alloy according to claim 8, characterized in that the proportion by weight of rare earths is higher than 0.3%.
18. The inoculant alloy according to claim 9, characterized in that the proportion by weight of rare earths is lower than 1%.
19. The use of an inoculant according to claim 12 for manufacturing cast-iron parts having portions with thicknesses larger than 20 mm.
20. The use of an inoculant according to claim 12 for manufacturing cast-iron parts having portions with thicknesses larger than 50 mm.
US14/441,761 2012-11-14 2013-11-12 Inoculant alloy for thick cast-iron parts Abandoned US20150284830A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
FR1260817A FR2997962B1 (en) 2012-11-14 2012-11-14 INOCULATING ALLOY FOR THICK PIECES IN CAST IRON
FR12/60817 2012-11-14
PCT/FR2013/052710 WO2014076404A1 (en) 2012-11-14 2013-11-12 Inoculant alloy for thick cast-iron parts

Publications (1)

Publication Number Publication Date
US20150284830A1 true US20150284830A1 (en) 2015-10-08

Family

ID=47666320

Family Applications (1)

Application Number Title Priority Date Filing Date
US14/441,761 Abandoned US20150284830A1 (en) 2012-11-14 2013-11-12 Inoculant alloy for thick cast-iron parts

Country Status (17)

Country Link
US (1) US20150284830A1 (en)
EP (1) EP2920335B1 (en)
JP (1) JP2016503460A (en)
KR (1) KR20150083998A (en)
CN (1) CN104812922A (en)
BR (1) BR112015010975A2 (en)
CA (1) CA2889124C (en)
DK (1) DK2920335T3 (en)
ES (1) ES2777934T3 (en)
FR (1) FR2997962B1 (en)
MX (1) MX2015006053A (en)
PL (1) PL2920335T3 (en)
PT (1) PT2920335T (en)
SI (1) SI2920335T1 (en)
UA (1) UA116218C2 (en)
WO (1) WO2014076404A1 (en)
ZA (1) ZA201503205B (en)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160138139A1 (en) * 2013-09-06 2016-05-19 Toshiba Kikai Kabushiki Kaisha Spheroidizing treatment method for molten metal of spheroidal graphite cast iron
EP3239307A1 (en) * 2016-04-29 2017-11-01 General Electric Company A ductile iron and process of forming a ductile iron component
EP3238854A1 (en) * 2016-04-29 2017-11-01 General Electric Company A ductile iron and process of forming a ductile iron component
NO20161091A1 (en) * 2016-06-30 2018-01-01 Elkem As Cast Iron Inoculant and Method for Production of Cast Iron Inoculant
US20180148805A1 (en) * 2015-05-18 2018-05-31 Toshiba Kikai Kabushiki Kaisha Method for treating molten cast iron
WO2019132672A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132668A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132669A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132671A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
CN115029495A (en) * 2022-06-15 2022-09-09 宜昌佳晟鑫铁合金有限公司 Pearlite inoculant formula
US11479828B2 (en) 2017-12-29 2022-10-25 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
CN115896604A (en) * 2022-11-15 2023-04-04 宜昌佳晟鑫铁合金有限公司 Silicon-based inoculant material proportioning method
US11846000B2 (en) 2016-06-30 2023-12-19 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105039631A (en) * 2015-08-20 2015-11-11 合肥市田源精铸有限公司 Nucleating agent containing rare earth and application of nucleating agent to spheroidal graphite cast iron smelting
CN111809103A (en) * 2020-07-21 2020-10-23 常州钜苓铸造有限公司 Preparation method of high-power wind power ultrahigh-strength high-toughness low-temperature nodular cast iron
WO2022202914A1 (en) * 2021-03-24 2022-09-29 日立金属株式会社 Spheroidal graphite cast iron, spheroidal graphite cast iron manufacturing method, and spheroidizing treatment agent

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995024508A1 (en) * 1994-03-09 1995-09-14 Elkem A/S Cast iron inoculant and method for production of cast iron inoculant
US20050018087A1 (en) * 2003-07-21 2005-01-27 Samsung Electronics Co., Ltd. Apparatus and method for detecting a 2:2 pull-down sequence
US20060011305A1 (en) * 2003-09-19 2006-01-19 Donald Sandell Automated seal applicator

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5767146A (en) 1980-10-11 1982-04-23 Osaka Tokushu Gokin Kk Introduction method for antimony into cast iron
FR2511044A1 (en) * 1981-08-04 1983-02-11 Nobel Bozel FERRO-ALLOY FOR THE TREATMENT OF INOCULATION OF SPHEROIDAL GRAPHITE FONT
JPS5943843A (en) * 1982-09-06 1984-03-12 Kusaka Reametaru Kenkyusho:Kk Additive alloy
US4666516A (en) * 1986-01-21 1987-05-19 Elkem Metals Company Gray cast iron inoculant
JPH02200718A (en) 1989-01-31 1990-08-09 Kiriyuu Kikai Kk Manufacture of spheroidal graphite niresist cast iron
JPH08188812A (en) * 1995-01-10 1996-07-23 Japan Trading Service:Kk Manufacture of high strength ductile cast iron
FR2750143B1 (en) * 1996-06-25 1998-08-14 Pechiney Electrometallurgie FERROALLIAGE FOR INOCULATION OF SPHEROIDAL GRAPHITE FOUNDS
FR2839082B1 (en) * 2002-04-29 2004-06-04 Pechiney Electrometallurgie ANTI MICRORETASSURE INOCULATING ALLOY FOR TREATMENT OF MOLD SHAPES
FR2855186B1 (en) * 2003-05-20 2005-06-24 Pechiney Electrometallurgie INOCULATING PRODUCTS CONTAINING BISMUTH AND RARE EARTHS
NO20045611D0 (en) 2004-12-23 2004-12-23 Elkem Materials Modifying agents for cast iron
JP4974591B2 (en) * 2005-12-07 2012-07-11 旭テック株式会社 Graphite spheroidizing agent and method for producing spheroidal graphite cast iron using the same
CN102002548A (en) * 2010-12-07 2011-04-06 哈尔滨工业大学 Nodularizer for nodular iron with thick section

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1995024508A1 (en) * 1994-03-09 1995-09-14 Elkem A/S Cast iron inoculant and method for production of cast iron inoculant
US20050018087A1 (en) * 2003-07-21 2005-01-27 Samsung Electronics Co., Ltd. Apparatus and method for detecting a 2:2 pull-down sequence
US20060011305A1 (en) * 2003-09-19 2006-01-19 Donald Sandell Automated seal applicator

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160138139A1 (en) * 2013-09-06 2016-05-19 Toshiba Kikai Kabushiki Kaisha Spheroidizing treatment method for molten metal of spheroidal graphite cast iron
US20180148805A1 (en) * 2015-05-18 2018-05-31 Toshiba Kikai Kabushiki Kaisha Method for treating molten cast iron
US10662510B2 (en) 2016-04-29 2020-05-26 General Electric Company Ductile iron composition and process of forming a ductile iron component
US10787726B2 (en) 2016-04-29 2020-09-29 General Electric Company Ductile iron composition and process of forming a ductile iron component
EP3238854A1 (en) * 2016-04-29 2017-11-01 General Electric Company A ductile iron and process of forming a ductile iron component
EP3239307A1 (en) * 2016-04-29 2017-11-01 General Electric Company A ductile iron and process of forming a ductile iron component
WO2018004357A1 (en) 2016-06-30 2018-01-04 Elkem As Cast iron inoculant and method for production of cast iron inoculant
NO347571B1 (en) * 2016-06-30 2024-01-15 Elkem Materials Cast Iron Inoculant and Method for Production of Cast Iron Inoculant
NO20161091A1 (en) * 2016-06-30 2018-01-01 Elkem As Cast Iron Inoculant and Method for Production of Cast Iron Inoculant
US11846000B2 (en) 2016-06-30 2023-12-19 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
US11098383B2 (en) * 2016-06-30 2021-08-24 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132668A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132671A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
US11479828B2 (en) 2017-12-29 2022-10-25 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
US11486011B2 (en) 2017-12-29 2022-11-01 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
US11486012B2 (en) 2017-12-29 2022-11-01 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
US11708618B2 (en) 2017-12-29 2023-07-25 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132669A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
WO2019132672A1 (en) 2017-12-29 2019-07-04 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
US11932913B2 (en) 2017-12-29 2024-03-19 Elkem Asa Cast iron inoculant and method for production of cast iron inoculant
CN115029495A (en) * 2022-06-15 2022-09-09 宜昌佳晟鑫铁合金有限公司 Pearlite inoculant formula
CN115896604A (en) * 2022-11-15 2023-04-04 宜昌佳晟鑫铁合金有限公司 Silicon-based inoculant material proportioning method

Also Published As

Publication number Publication date
KR20150083998A (en) 2015-07-21
CA2889124A1 (en) 2014-05-22
SI2920335T1 (en) 2020-03-31
EP2920335A1 (en) 2015-09-23
WO2014076404A1 (en) 2014-05-22
CN104812922A (en) 2015-07-29
EP2920335B1 (en) 2019-12-18
UA116218C2 (en) 2018-02-26
ZA201503205B (en) 2016-10-26
PT2920335T (en) 2020-03-17
MX2015006053A (en) 2015-11-23
BR112015010975A2 (en) 2017-07-11
FR2997962B1 (en) 2015-04-10
JP2016503460A (en) 2016-02-04
CA2889124C (en) 2020-12-29
PL2920335T3 (en) 2020-05-18
ES2777934T3 (en) 2020-08-06
DK2920335T3 (en) 2020-03-16
FR2997962A1 (en) 2014-05-16

Similar Documents

Publication Publication Date Title
US20150284830A1 (en) Inoculant alloy for thick cast-iron parts
EP3478858B1 (en) Cast iron inoculant and method for production of cast iron inoculant
KR102494632B1 (en) Cast iron inoculants and methods of producing cast iron inoculants
KR102410368B1 (en) Cast iron inoculum and method of producing cast iron inoculant
EP3732306B1 (en) Cast iron inoculant and method for production of cast iron inoculant
KR102493172B1 (en) Cast iron inoculants and methods of producing cast iron inoculants
EP3732305B1 (en) Cast iron inoculant and method for production of cast iron inoculant
JP6993646B2 (en) Inoculant for cast iron
CN106544462B (en) A kind of nodular cast iron inoculant and its preparation method and application
RU2337972C2 (en) Fluxed cored wire filler for desulfurising and modification of cast iron
CN108950367B (en) Preparation method of high-performance nodular cast iron
CN118028691A (en) Ductile iron casting formula and operation process
JPH04358039A (en) Additive alloy

Legal Events

Date Code Title Description
AS Assignment

Owner name: FERROPEM, FRANCE

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:FAY, AURELIE;TOUMI, MOURAD;MARGARIA, THOMAS;AND OTHERS;SIGNING DATES FROM 20150511 TO 20150523;REEL/FRAME:035818/0069

STPP Information on status: patent application and granting procedure in general

Free format text: NON FINAL ACTION MAILED

STCB Information on status: application discontinuation

Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION