Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C37/00—Cast-iron alloys
  • C22C37/10—Cast-iron alloys containing aluminium or silicon
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D19/00—Casting in, on, or around objects which form part of the product
  • B22D19/14—Casting in, on, or around objects which form part of the product the objects being filamentary or particulate in form
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B22—CASTING; POWDER METALLURGY
  • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
  • B22D27/00—Treating the metal in the mould while it is molten or ductile ; Pressure or vacuum casting
  • B22D27/20—Measures not previously mentioned for influencing the grain structure or texture; Selection of compositions therefor
• • 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
  • C21C1/08—Manufacture of cast-iron
• • 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
  • C21C1/10—Making spheroidal graphite cast-iron
• • 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
  • C21C1/10—Making spheroidal graphite cast-iron
  • C21C1/105—Nodularising additive agents
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C28/00—Alloys based on a metal not provided for in groups C22C5/00 - C22C27/00
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
  • C22C29/18—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on silicides
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/02—Making ferrous alloys by powder metallurgy
  • C22C33/0242—Making ferrous alloys by powder metallurgy using the impregnating technique
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/02—Making ferrous alloys by powder metallurgy
  • C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
  • C22C33/0264—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements the maximum content of each alloying element not exceeding 5%
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/02—Making ferrous alloys by powder metallurgy
  • C22C33/0257—Making ferrous alloys by powder metallurgy characterised by the range of the alloying elements
  • C22C33/0278—Making 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%
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C33/00—Making ferrous alloys
  • C22C33/08—Making cast-iron alloys

Definitions

• the present invention relates to an inoculant alloy for the treatment of cast iron.
• Cast iron is a well-known iron-carbon alloy and widely used for the manufacture of mechanical parts.
• the melt is obtained by mixing the constituents of the alloy in the liquid state at a temperature of between 1320 and 1450 ° C. before pouring into a mold and cooling the alloy obtained.
• the carbon can adopt several physico-chemical structures depending on several parameters.
• White cast iron has the characteristic of being hard and brittle, which is undesirable for some applications.
• Gray cast iron is softer and can be worked.
• the liquid iron undergoes an inoculation treatment to introduce in the cast graphitizing components or supports to graphitization commonly called germs that will promote, when cooling the cast iron in the mold, the appearance of graphite rather than iron carbide.
• the components of an inoculant are thus elements promoting the formation of graphite and the decomposition of iron carbide during the solidification of the iron.
• an inoculant may be designed to perform other functions and include for this purpose other components having a special effect.
• Cast iron may also undergo additional pretreatment or subsequent treatment.
• the desired properties may be obtained, whether the graphite formed is spheroidal, vermicular or lamellar.
• One or the other graphitic form can be obtained preferentially by a particular treatment of the cast iron using specific components.
• spheroidal graphite may be favored by a so-called nodulising treatment aimed mainly at providing the magnesium melt in sufficient quantity so that the graphite can grow so as to form round particles (spheroids or nodules).
• nodulizing components are generally added as a specific alloy (nodulizing alloy) prior to the inoculant treatment of the cast iron during a particular treatment.
• the nodulising alloy essentially affects the shape of the nodules of graphite, while the inoculating product aims to increase the number of nodules and homogenize the graphitic structures.
• These treatments can be performed in one or more times and at different times during the manufacture of the cast iron.
• inoculants are conventionally made from a ferro-silicon alloy type FeSi 45, FeSi or FeSi65 May 7 with adjustment of chemistry the following composition referred inoculant. It can also be mixtures of several alloys.
• the inoculation efficiency of the cast iron part also depends on its thickness (or the rate of solidification).
• the formation of degenerate graphite and / or "chunky" graphite can reduce the mechanical properties of the cast iron.
• the smelter usually proceeds to the addition of pure antimony in the liquid metal.
• the addition of pure antimony in the liquid metal poses problems of precision because the rate of introduction is very low (of the order of 10 to 30 g per ton of liquid iron).
• the addition yield of pure antimony is between 50 and 80% and the useful amount introduced is therefore difficult to control.
• degraded graphite may form in the structure.
• the antimony will tend to strongly increase the proportion of perlite, unwanted phase in the ferritic structures.
• the smelter In the case of adding pure antimony, the smelter must also associate rare earth (abbreviated TR or RE for "Rare Earths”) in order to obtain a maximum improvement of the shape of the graphite. Similarly, if the amount of rare earth is insufficient, the piece will have a graphite defect type "spiky”. Conversely, if the amount of rare earth is too high, the graphite defect will be more of a "chunky" type, which essentially happens when the raw materials used are relatively pure.
• TR or RE Rare earth
• Such a disadvantage according to these documents for thin parts includes, in particular, the fact that it is based on ferro-silicon and comprises between 0.005 and 3% by mass of rare earths, in particular lanthanum, as well as between 0.005 and 3% by weight of bismuth, lead or antimony in a ratio of rare earths / (Bismuth + Lead + Antimony) of between 0.9 and 2.2; bismuth being particularly preferred, the descriptions of these documents relating only to bismuth.
• WO2006 / 068487A1 discloses an inoculant comprising a phase-modifying component (inoculant function) associated with a graphite structure modifying agent which may be antimony.
• a phase-modifying component inoculant function
• a graphite structure modifying agent which may be antimony.
• this structural modifying agent is used in admixture with the inoculant compound (ferrosilicon) and not in the alloyed form.
• Antimony is also clearly mentioned as a perlite promoter, a phase which, as mentioned above, is not generally desired.
• the amount of antimony used is between 3 and 15%, which corresponds to a significant amount probably responsible for the proportion of pearlite formed.
• J P220071 8A discloses an inoculant consisting of a mixture of ferrosil hereum, antimony, calcium silicide and rare earths. Antimony is not used in allied form.
• JP57067146A describes a ferrosilicon-based alloy comprising between 5 and 50% by weight of antimony and up to 10% of rare earths. In addition to 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 the treatment of ferrous silicon-based cast iron thick pieces, containing between 0.005 and 3% by mass of rare earths, characterized in that it also contains between 0.2 and 2% by weight of antimony.
• antimony in the form of an alloy makes it possible to achieve a high efficiency of use of antimony, of the order of 97 to 99%.
• the useful quantity introduced is therefore much more precisely known.
• the increase of the yield thus allows a saving of the products and simplifies the management of the additions of products, this including for the rare earths.
• an alloy according to the invention makes it possible to limit the gaseous release 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 earth combination lengthens the fade time of antimony significantly. This produces a longer effect in the complete foundry process. It should be noted that the fade time of antimony is even greater than the fade time of bismuth in inoculant alloys for thin parts.
• the alloy according to the present application when added in the bag or in the oven, may thus make it possible to replace or even eliminate an additional inoculation to the jet or late.
• the alloy according to the present application also makes it possible especially to limit greatly or even to avoid the formation of "chunky” or “spiky” type graphite defects, but also to improve the shape of the graphite by ensuring a nodularity greater than 95% while bringing the spheroids closer to the perfect sphere.
• the alloy according to the present application thus ensures a homogeneous ferrite / perlite matrix according to the different thicknesses of the manufactured part, which notably improves the subsequent machining conditions of the part.
• the antimony ratio on rare earths will be greater than 1, 4, preferably 1, 6, and less than 2.5; preferably less than 2.
• the inoculant alloy also comprises magnesium. It will then be a nodulizer with additional inoculant effect.
• antimony made it possible to obtain a better yield of the magnesium introduced into the melt.
• the inoculant alloy does not contain magnesium.
• the ratio of rare earths to antimony is between 0.9 and 2.2.
• the mass proportion of antimony is greater than 0.3%, preferably greater than 0.5%, more preferably greater than 0.8%.
• the mass proportion of antimony is less than 1, 5%, preferably less than 1, 3%.
• the rare earths comprise lanthanum, preferably only lanthanum.
• the mass ratio of rare earths is greater than 0.2%, preferably greater than 0.3%.
• the mass ratio of rare earths is less than 1, 2%, preferably less than 1%.
• the present invention also relates to the use of the inoculant according to the invention.
• said inoculant is introduced in powder form.
• 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 is aimed at producing cast iron parts having parts of thickness greater than 6 mm, preferably parts with thicknesses greater than 20 mm, and even more preferentially parts of thickness greater than 50mm.
• the inoculant according to the invention will typically be used in the context of an inoculation of a melt bath. It can also be used in pre-conditioning of said cast iron and as a noduliser if necessary.
• composition of an inoculating alloy according to the invention may comprise, for example:
• the inoculant may also include additional elements providing particular effects depending on the desired properties. This may be more particularly the case in the context of a pre-conditioning treatment of cast iron.
• the inoculant alloy may thus have the following composition:
• An inoculation treatment will typically consist of the addition of 0.05 (preferably at least 0.1%) to 0.8% by weight of the inoculant in the melt bath, especially in the following conditions. for example:
• the preconditioning inoculant may in particular be added in the form of a cored wire.
• the frequency range of the harmful agent according to the invention can be adapted according to its addition modalities.
• Addition before casting in the slack particle size of between about 0.2 and about 0.5 to 2 mm.
• the inoculant mixture can also be added successfully as an inoculant before filling the casting mold or in inoculation in the bag or later, after adjusting the chemistry of the alloy (especially Ba between 1.5% and 5%). mass and Ca between 0.5 and 2% mass).
• composition of the alloy will also include magnesium.
• composition of such a nodulising alloy with inoculant function may be as follows:
• the generalization of the nodulizer (especially with inoculant function) according to the invention will be adapted according to the size of the treatment pockets. For example, for bags of 100 to 500 kg of cast iron, preference will be given to a particle size of between about 0.4 and about 2 mm, or even up to 7 mm. For pockets of 500 to 1000 kg of cast iron, preference will be given to a particle size of between about 2 and about 7 mm, or between about 10 and about 30 mm. For pockets of more than 1000 kg of cast iron, preference will be given to a particle size of between about 10 and about 30 mm.
• Example 1 foundry A - piece of thickness 8 mm.
• the liquid iron was treated by adding in the induction furnace pure antimony in a proportion of 30 g of antimony per one ton of liquid iron.
• the cast iron was then subjected to nodulisation treatment using a FeSiMg type nodulising alloy comprising one third of a FeSiMg alloy comprising 2% of light earth and one third of a FeSi alloy.
• Mg does not include rare earths.
• the cast iron finally underwent an inoculation treatment by adding 0.1% by weight of a FeSiMnZr alloy and 0.1% of an alloy to the tundish.
• FeSiAI the inoculant alloys being added as inoculant insert in the mold.
• the step of adding pure antimony was suppressed and the nodulizing treatment was simplified using only the non-rare earth FeSiMg nodulising alloy.
• the foundry A treated with an inoculant according to the present application showed an increase in tensile elongation on control specimens for a grade EN-GJS-400-15.
• Example 2 foundry B - piece 200 mm thick. Foundry Reference (B1)
• the liquid iron was treated by adding in the induction furnace pure antimony in a proportion of 20 g of antimony per one ton of liquid iron.
• the cast iron was then subjected to a nodulisation treatment using a FeSiMg type nodulising alloy comprising 1% by weight of rare earths and introduced into the cast iron in the form of a cored wire.
• the cast iron finally underwent an inoculation treatment by adding 0.15% by weight of a FeSiBiTR alloy to the casting basin.
• the step of adding pure antimony was suppressed and the nodulizing treatment was simplified using only a FeSiMg nodulising alloy not containing rare earths (also introduced in the form of cored wire).
• Example 3 foundry C - thin pieces (thickness less than
• the liquid iron was treated by adding in the induction furnace pure antimony in a proportion of 25 g of antimony per one ton of liquid iron.
• the pig iron then underwent a nodulisation treatment using a nodulising alloy of FeSiMg type comprising 6.7% by weight of magnesium as well as 1.2% of calcium and 0.98% of rare earths.
• the cast has finally undergone a late inoculation treatment by adding
• a nodulising alloy with inoculant function according to the composition 3 mentioned above was used.
• the step of adding pure antimony has been removed.
• the nodulising treatment was carried out using a FeSiMg-type alloy according to composition 3 of the present application and comprising 6.4% by weight of magnesium and 1.3% of calcium, 0.6% by weight. antimony and 1.2% rare earths.
• the additional inoculation could be done using a more economical inoculant of the FeSiAICa type.
• Example 4 foundry D - massive pieces
• the liquid iron was treated by adding in the induction furnace pure antimony in a proportion of 30 g of antimony per one ton of liquid iron.
• the pig iron then underwent a nodulisation treatment using a nodulising alloy of FeSiMg type comprising 9.1% by weight of magnesium as well as 1.4% of calcium and 1.1% of rare earths.
• the cast iron finally underwent an inoculation treatment by adding an insert of 10 kg per ton of cast iron of a FeSiMnZr inoculating alloy.
• the step of adding pure antimony has been removed.
• the nodulising treatment was carried out using the same alloy as for the reference, namely by using a nodulising alloy of FeSiMg type comprising 9.1% by weight of magnesium and 1.4% of calcium and 1, 1% rare earths.
• the D-cast iron makes it possible to elaborate a shade of EN-GJS-400-18-LT darkening used in particular in the wind energy sector.
• the use of the inoculant according to the demand has made it possible to increase the impact resistance significantly.
• Example 5 Foundry E - thin parts and nodulising treatment.
• the molten iron was subjected to a nodulisation treatment using a FeSiMg type nodulising alloy comprising 9.1% by weight of magnesium and 0.8% of bismuth and 0.7% of rare earths.
• the melt then underwent inoculation treatment according to a late inoculation method by adding 0.18% of a FeSiMnZr alloy having a particle size of between 0.2 and 5 mm.
• a nodulising alloy according to the composition 3 mentioned above was used.
• the alloy used is a FeSiMg type alloy comprising 9.1% magnesium and 0.75% antimony and 0.5% rare earths.
• the melt then underwent an additional inoculation treatment according to a late inoculation method by adding 0.17% of a FeSiMnZr alloy having a particle size of between 0.2 and 5 mm.
• the foundry reference (F1) and the test (F2) using an inoculant alloy according to the application were made according to Example 4 and the foundry D by inoculating massive pieces.
• the foundry reference (G1) and the test (G2) using an inoculant alloy according to the application were carried out according to Example 4 and the foundry D by inoculating massive pieces.
• Example 8 foundry H - piece 150 mm thick.
• the liquid iron was treated by adding in the induction furnace pure antimony in a proportion of 15 g of antimony per one ton of liquid iron.
• the cast iron then underwent a nodulisation treatment with a nodulated thicker wire (diameter 13 mm, 32% Mg, 1.2% TR, 230 g / m powder)
• the cast iron finally underwent a late inoculation treatment by adding to the casting jet 0.15% by weight of a FeSiMnZr alloy.
• the step of adding pure antimony was suppressed and the nodulizing treatment was simplified using only a FeSiMg nodulising alloy not containing rare earths (also introduced in the form of cored wire).

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Materials 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)

Priority Applications (13)

Applications Claiming Priority (2)

Publications (1)

Family

ID=47666320

Family Applications (1)

Country Status (17)

Cited By (2)

Families Citing this family (14)

Citations (7)

Family Cites Families (8)

• 2012
  • 2012-11-14 FR FR1260817A patent/FR2997962B1/fr active Active
• 2013
  • 2013-11-12 BR BR112015010975A patent/BR112015010975A2/pt not_active Application Discontinuation
  • 2013-11-12 US US14/441,761 patent/US20150284830A1/en not_active Abandoned
  • 2013-11-12 UA UAA201505800A patent/UA116218C2/uk unknown
  • 2013-11-12 CA CA2889124A patent/CA2889124C/fr active Active
  • 2013-11-12 SI SI201331674T patent/SI2920335T1/sl unknown
  • 2013-11-12 EP EP13801650.6A patent/EP2920335B1/fr active Active
  • 2013-11-12 CN CN201380059199.9A patent/CN104812922A/zh active Pending
  • 2013-11-12 WO PCT/FR2013/052710 patent/WO2014076404A1/fr active Application Filing
  • 2013-11-12 ES ES13801650T patent/ES2777934T3/es active Active
  • 2013-11-12 JP JP2015542331A patent/JP2016503460A/ja active Pending
  • 2013-11-12 PT PT138016506T patent/PT2920335T/pt unknown
  • 2013-11-12 PL PL13801650T patent/PL2920335T3/pl unknown
  • 2013-11-12 KR KR1020157011457A patent/KR20150083998A/ko not_active Application Discontinuation
  • 2013-11-12 MX MX2015006053A patent/MX2015006053A/es unknown
  • 2013-11-12 DK DK13801650.6T patent/DK2920335T3/da active
• 2015
  • 2015-05-08 ZA ZA2015/03205A patent/ZA201503205B/en unknown

Patent Citations (7)

Also Published As

Similar Documents

Legal Events