Method of iron modification |
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
IPC classes for russian patent Method of iron modification (RU 2515160):
 Making of cold-resistant cast iron / 2509159
Cast iron melt is processed in the mould by feeding modifying mix. The latter contains a spheroidising additive composed of ferromagnesium silicon and graphitising additive composed of boric acid. Said additives are added in amounts that allows obtaining 0.03-0.06% of residual magnesium and 0.005-0.007% of boron in finished casting. Then, spontaneous annealing of casting is performed in the mould for 60 minutes.
 Method for ladle modification of molten cast iron with light-weight magnesium-containing alloy combinations / 2500819
In rear part of a ladle bottom, opposite its nose part, there located by means of an inclined chute depending on weight of treated cast iron is one or more molten welded tightly closed containers from steel sheets with thickness of 1.5…2.0 mm, with tightly packed spheroidising modifying agent in the form of magnesium-containing alloy combination and bulk volume of up to 10 kg; after that, the ladle is intensely filled with molten cast iron for the period of not more than 40 seconds with direction of a jet to a free part of the ladle bottom.
 Method for obtaining high-strength cast-iron with vermicular graphite by intra-mould modification using alloy combinations of fe-si-rem system / 2497954
Method involves loading to a reaction chamber of a pouring gate system of modifying agent charge in the form of Fe-Si-REM alloy combination providing initial concentration of rare-earth metals in molten cast-iron of 0.075%; then, after the casting mould is assembled, a lump of FS75 with the weight of 0.24-0.46% of metal consumption of the mould is laid in its pouring basin for graphitising pre-modification, and it is filled with molten cast-iron from the furnace.
 Method for obtaining nanostructured recarburising agent for out-of-furnace treatment of high-strength cast-iron with ball-shaped and compacted graphite / 2495134
Method involves preparation of carbon-containing composition containing the following components, wt %: anthracite 50-85, graphite scrap 5-25, broken electrodes 5-25, graphite structure 5-15 that is crushed to the fraction of 0.1-3.2 mm, burnt at the temperature of 500-1500°C, graphite spheroids are formed in the material structure at high specific pressure of up to 20 GPa and subject to high-temperature exposure at 1800-2500°C in a reducing medium so that graphite nanostructures with the size of up to 100 nm are formed, which represent graphite nanoclusters with a hexagonal pattern.
Production method of high-strength cast-irons with ball-shaped or compacted graphite based on nanostructured recarburising agent / 2495133
Proposed method involves melting of a charge in a melting unit, heat treatment of the melt at 1300…1650°C; at that, when obtaining cast-iron with ball-shaped graphite, primary modification is performed with nanostructured recarburising agent in the quantity of 0.10…0.25% of the melt weight, and secondary spheroidising modification is performed by means of a modifying agent containing 5…7% of magnesium, in the quantity of 1.2…2.0% of the melt weight, and when obtaining cast-iron with compacted graphite, primary modification is performed with nanostructured recarburising agent in the quantity of 0.10…0.25% of the melt weight, and secondary compacting modification is performed with a modifying agent containing 3…5% of magnesium and 3…6% of rare-earth elements in the quantity of 0.3…0.8% of the melt weight.
Method of production of aluminium iron with compact inclusions of graphite / 2487950
Proposed method comprises making iron melt with aluminium content of 9.8-19.7%, pouring said melt in metal mould placed in salt melt at 950-1100°C, cooling said melt and isothermal curing of crystallised casting at 950-1100°C for 0.5-2 hours.
Alloy combination for production of castings from high-strength cast-iron (versions) / 2480530
As per Version 1, alloy combination contains the following, wt %: silicon 22.0-30.0, magnesium 9.0-12.0, cerium 0.4-0.6, copper is the rest; as per Version 2, alloy combination contains the following, wt %: silicon 22.0-30.0; magnesium 9.0-12.0, misch metal 0.8-1.2, and copper is the rest.
Modifying agent for obtaining cast iron with spherical graphite / 2445387
Modifying agent contains the following, wt %: magnesium 7.0-9.0; cerium 8.0-10.0; iron ≤ 1.5; nickel is the rest.
 Cast iron properties influence method / 2444729
In cast iron properties influence method there measured by addition of magnesium to cast iron melt is content of oxygen in cast iron melt; at that, to cast iron melt there added is magnesium till oxygen content in cast iron melt at temperature of about 1420°C is about 0.005-0.2 ppm. At that, magnesium is added till oxygen content is less than 0.1 ppm, preferably between 0.08 and 0.1 ppm.
 Procedure for production of iron with vermiculite graphite / 2427660
Procedure consists in melting charge in electric furnace, in heating iron melt in it to temperature 1490-1510°C and in modification of produced melt in ladle with mixture containing complex addition alloy FSMg7 containing REM (rare earth metals) 0.3-1.0 %, magnesium 6.5-8.5 %, at amount of 0.2-0.5 % and 22 % silicobarium SIBAR22 at amount 1.5-2.0 % of weight of treated iron melt.
Briquette used in manufacture of cast iron / 2247155
Briquette includes silicon-containing material, carbon-containing material, and cement as binder. Silicon-containing material includes metallurgical silicon carbide and carbon-containing material includes carbon-siliceous mixture.
 Modifying agent / 2247170
Claimed modifying agent contains (mass %) ferrosilicon barium 0.5-5.0 and gypsum 25-5 %.
Method of production of ingots made out of mottled cast iron with austenitic-bainite structure / 2250268
The invention is dealt with metallurgy, in particular, with development of a method of production of mottled cast irons with globular graphite, which may be used for manufacture of components being worn under action of increased loadings. The method provides, that the mottled cast iron is melted down in the induction furnace, the liquid melt at pouring into a ladle is modified with magnesium-bearing addition alloys for formation of the ball-shaped graphite impurities in the ingots and during casting into a sandy-argillaceous mold expos it to inoculating modification. The ingots after crystallization are pulled out from the molds at the temperature of 900-1000°C, transposed to a furnace with temperature of 950-1000°C and keep there during 10-30 mines. After the aging the ingot is exposed to quenching in an isothermal bath at the temperature of 300-320°C within 1-1.5 hour. At that they use the cast iron of following chemical composition, (in mass %): carbon - 3.2-3.4, silicon - 3.0-3.3, manganese - 0.3-0.4, magnesium - 0.04-0.07, molybdenum - 1.5-1.7, nickel - 2.2-2.6, sulfur - 0.01-0.012, phosphorus - 0.06-0.08, iron - the rest. The invention allows to obtain a mottled cast iron with globular graphite and austenitic-bainite structure, high impact resistance, strength, hardness, wear resistance and quasi-isotropy.
Modifying master alloy for cast iron producing method / 2277589
Method comprises steps of preparing, heating, pouring and crystallizing melt under protective flux. Melt is heated till temperature higher than liquidus temperature t1 by 10 - 99°C; pressure value is in range 10-3 - 0.9 x 10-1 MPa. Invention allows prepare modifying master alloy with easy-to-melt magnesium-containing component, with high density and uniform distribution of properties in the whole volume.
 Semifinished product of foundry cast iron and method of its production / 2312161
Proposed semifinished product is made from composition system of white cast iron. Structure contains, independently or in complex, spheroidal or flattened particles of graphite whose outer surface is partially or fully coated with ferrite. Particles are dispersed at density of 50 particles/mm2 or more. Cast iron is produced by casting the melt of white cast iron constituents containing the spheroidizing agent. After casting, rolling and heat treatment are performed for obtaining spheroidal particles of graphite or heating and hot rolling are performed for obtaining flattened particles of graphite.
Complex modifying agent for producing cast pieces of cast iron with vermiculite or compact graphite / 2323270
Complex modifying agent contains next relation of components, mass %: magnesium, 0.5 - 10; calcium, 0.1 - 10; aluminum, 0.1 - 10; silicon, 30 - 80; total content of cerium and yttrium, 0.5 - 15; manganese, 0.1 - 15; lanthanum, 0.001 - 10; magnesia, 0.001 - 5; total content of oxides of rare earth metals, 0.001 - 10; iron, the balance.
Synthetic cast iron production method / 2324742
Invention concerns the siderurgy area and may be used when manufacturing the remelting fabricating parts that are used in the cast iron foundry production. The metal stock is loaded for melting inside an induction furnace until the melted down composition is obtained. In the furnace, upon the mirror of fusion the carbonates of the alkaline-earth metals are introduced in amounts of 10-20%, and the carboniferous material depending upon the required chemical composition of cast iron. The invention permits to intensify impregnation with carbon process, eradicates occurrence of refining foam and facilitates the sulfur removal.
 Fluxed cored wire filler for desulfurising and modification of cast iron / 2337972
Invention concerns metallurgy field and can be used in foundry. Particularly it is used for desulfurising and modification of cast iron and receiving of cast iron products with structure of globular and vermicular graphite. Filler contains, wt %: 18÷75 magnesium, part of which is introduced in metal phase; aluminium, barium, calcium, titanium, rare-earth metals at its total content 1÷10, and also iron and silicon (as the rest) - in the form of one or several materials, choose from group, including ferrosilicium, magnesium - iron - silicon alloy; mixture of metal silicon with cast iron and/or steel rattle, and/or chip, and/or powder. In filler content can also be included passivator in the form of one or several materials from group, including fired dolomite, calcium fluoride, calcium carbide, silicon carbide, soda, in amount which is a part of total content in filler of iron and silicon.
 Control mode of process for manufacturing graphite and high-duty cast iron with globular and vermicular graphite for casting receiving / 2337973
Invention concerns metallurgy field, foundry. Particularly it concerns control modes of grey and high-duty cast iron and can be used at single-piece, large-scale and mass production of cast iron castings. In method there is received basic alloy of cast iron with usage of alloying, modifying and graphitising admixtures, process qualities are controlled and corrected including operation by effect of spheroidising and vermiculising modification at the section of casting mold charging. It is implemented one-time ladleman cast iron treatment, making preliminary calculation the quantity of alloying, modifying and graphitising admixtures depending on weight of liquid metal, containing of sulphur and oxygen, basic elements and alloying inside of basic cast iron melt and time of holding modifying effect, at that control of all process parameters is outfitted by overall video surveillance system for manufacturing operations with registration and delivering of received results into computer data base and to the lighting panel. Finishing of modifying effect is alerted by acoustic alarm.
 Ligature for modification of high-strength cast irons, method of its receiving and usage / 2355803
Invention relates to metallurgy field, particularly to magnesium-bearing ligature making practice for high-strength ligatures, used for manufacturing of hard part, for instance automobile crankshaft. Ligature contains, wt %: magnesium 17-20, cerium 0.4-0.6, copper is the rest. In the method in the capacity of integumentary flux it is used powdered baric flux, which is charged on magnesium, copper is fractional introduced: at first 60-70 wt % of its total amount, and then - by 10 wt % by components melting with addition of flux for saving of melt blanket, process is implemented at the temperature 725-800°C, chosen on the basis of binary constitution diagram Mg-Cu, during 40-60 min with conclusive layer induction of refining flux of thickness 1-2 cm and introduction of cerium with solid subsurface mixing of received ligature. Then ligature is crushed for pieces 2-4 kg, after what it is introduced into the cast iron in amount 0.65-0.85 wt % of cast iron weight.
|
FIELD: metallurgy. SUBSTANCE: proposed method comprises furnacing of preset-composition iron, filling the cover material on iron surface for it to be cured to a dense thick cover, and adding of hard modifier based on cerium, magnesium and nickel. Said hard modifier is held in water before adding to the melt. Iron furnacing and modifying are performed in induction furnace mould at iron melt level not higher then induction furnace top coil level and at inductor current frequency of 50-2400 Hz. Note that prior to filling the cover material on iron surface, rated power fed to furnace inductor is decreased by 5-50%. Now, produced iron is discharged into ladle. EFFECT: higher efficiency of distribution of magnesium and cerium over the entire volume of liquid iron to be filled in the mould. 9 cl, 1 tbl
The invention relates to metallurgy and foundry, in particular to a method of obtaining modified nodular cast iron, which can be used for the manufacture of machine parts and equipment. A known method of inoculation of liquid iron under a loose cover material, including the production of pig iron a given composition, placing a layer of solid crushed modifier at the bottom of the bucket, coating the surface modifier layer of the coating material, filling the ladle with the molten iron and backfilling mirrors of liquid iron in the same cover material, which consists of carbon passivator (crushed coke) and insulating additives (expanded perlite). (SU 1077929, SS 1/10 published 07.03.1984) In the process of modifying the liquid iron in the lower layers, located at the bottom of the bucket, bubbles of vapor of magnesium from the solid particles ligature during its contact with the melt. During their ascent to the surface of the melt is the absorption of magnesium cast iron. This process of modifying the allocation ratio of magnesium by volume of iron is 0.8. However, the disadvantages of this method are the low percentage of absorption of magnesium melt (55-65%). The closest in technical essence and the achieved technical result is with the persons inoculation of liquid iron, including smelting furnace cast iron specified composition, discharge from the melting furnace melt in the ladle, filling the mirrors of liquid iron with coating material powder of fluspirilene "Barrier", which, coahulia the slag forms a dense viscous cover, introduction through the gap between the lining of the ladle and cover material in the molten cast iron solid heavy modifier based on cerium, magnesium and Nickel and the filling of the gap with coating material. In this process, the absorption of magnesium and cerium reaches 95%. (EN 2422546, SS 1/10, published on 27.06.2011) The modification of the molten cast iron is in the process of lowering the modifier in the bottom part of the bucket. Therefore, the disadvantage of this method of modification is low distribution coefficient of magnesium and cerium volume of liquid iron (up to 0.6)in the bucket. The absorption of magnesium and cerium upper layers of the melt in the ladle is to a greater extent than the lower. So casting obtained from the metal of the upper layers of the bucket, contain 95% of graphite regular shape, and casting obtained from the metal of the lower layers of the bucket, is 55%, which affects the strength characteristics of these castings. The invention and its technical result is to increase the distribution ratio of magnesium and cerium volume of liquid iron, which will pour casting f is RMI. The technical result is achieved in that a method of obtaining modified cast iron includes the production of pig iron a given composition, filling in the mirror cast iron coating material, extract it to form a tight viscous cover and introduction into the melt of the solid modifier based on cerium, magnesium and Nickel, and before the introduction of the melt modifier stand in the water, and smelting and the inoculation is carried out in the crucible induction furnace with the current frequency 50-2400 Hz at the level of the molten cast iron is not above the level of the upper coil inductor furnace, before the filling of the coating material on 5-50% reduce the amount of nominal power applied to the inductor furnace, then the modified cast iron is poured into a ladle. The technical result is also reached by the fact that when the frequency of the inductor current 2400 Hz filling of the coating material and the introduction of the modifier is carried out after the reduction of the nominal power applied to the inductor furnace, 5-15%; when the frequency of the inductor current 500 Hz the filling of the coating material and the introduction of the modifier is carried out after the reduction of the nominal power applied to the inductor furnace, 15-25%; when the frequency of the inductor current 50 Hz filling of the coating material and the introduction of the modifier is carried out after the reduction of the nominal power applied to the inductor furnace, is as 40-50%; solid modifier is injected between the lining of the crucible and coating material; the time of introduction into the melt of the solid modifier is less than 5 seconds; solid modifier is administered in the amount of 1.0 to 1.5% by weight of modified liquid iron; the introduction of solid modifier in the melt of cast iron covered cover material; coating material using powder fluspirilene "Barrier". The method according to the invention can be illustrated by the following example. To melt the iron charge materials and melting alloy cast iron of a given composition used mid-frequency (500 Hz) induction furnace. When conducting the process at rated power inductor is process intensive mixing of the melt, which makes it possible to form on the surface of the melt protective cover. When the temperature of liquid iron 1440°With reduced nominal power applied to the inductor furnace, at 20-21% and covered the mirror melt coating material powder of fluspirilene "Barrier" in the amount of 0.5% by weight of the treated melt. When the melt level in the crucible is not above the level of the upper coil inductor furnace and the emergence of a convex meniscus of the melt at lower power conditions are created rapid tightening of solid modifier in Donne the second part of the crucible furnace, where was his dissolution, which ensured the increase of the coefficient of distribution of magnesium and cerium volume of liquid metal. This formed after exposure of the powder fluspirilene dense viscous cover is not destroyed. Then in liquid iron between the lining of the crucible induction furnace and the coating material was introduced by a famous firm of spheroidizing inoculant based on cerium, magnesium and Nickel in the amount of 1.0% by weight of the treated melt. The modifier contained magnesium, cerium, iron and Nickel in the following ratio, wt. %: magnesium 7,0-8,0, cerium 8,0-10,0, iron ≤ 1.5A, Ni - rest. Before introduction into the melt of the solid modifier previously stood in the water for a time (a few minutes)sufficient for impregnation with water and oxidation of the outer surface of the components. Due to this, in combination with a decrease in the intensity of stirring of the melt from the reduction of the nominal power applied to the inductor, the beginning of the interaction of the modifier with the melt occurred with a delay, i.e. after 5 seconds after the introduction of the modifier in the melt, and proceeded less rapidly. The introduction of the modifier in the melt was 4 sec, and then place the introduction was filled with powder fluspirilene "Barrier". Delay intensive interaction between the modifier and melt about what went down, due to the formation around the particles modifier steam cushion and the oxidation of its outer surface. Due to this, the combustion of magnesium and cerium at the initial stage of interaction of components of the modifier and the melt was observed, which reduced their stupor. Additionally, the discharge of liquid iron from the crucible induction furnace into a ladle of its lower layers are mixed with the upper layers due to which the distribution coefficient of magnesium and cerium by volume of melt more aligned and reaches 0,96. After the inoculation of cast iron had the following content of elements, wt. %: carbon 3,5, silicon 1,8, chrome 8,0, manganese 1,0, Nickel 4,5, boron 0,3, vanadium 0, 6, copper 0,4, cerium 0.03, magnesium 0.03, iron rest. Similar results were obtained by carrying out the method according to the invention on the other induction furnaces with different frequency characteristics. For high-frequency induction furnace with a current frequency of the inductor 2400 Hz achievement of the technical result is achieved when the filling of the coating material and the introduction of the modifier after reducing the nominal power applied to the inductor furnace, 5-15%, and for low-frequency induction furnace with a frequency inductor current 50 Hz - after reducing the nominal power applied to the inductor furnace, by 40-50%. The results of a comparative is about the analysis of the known method and the method according to the invention to obtain a modification of nodular cast iron is given in the table. The data in the table suggests that the modification of the melt in the crucible induction furnace operating contributes to the increase of the coefficient of distribution of magnesium and cerium by volume of the melt in the ladle from 0.6 to from 0.88 to 0.98, and the number (average) of the spherical graphite is increased from 65 to 86-95%.
1. The method of obtaining modified nodular cast iron, including viplav the iron of a given composition, filling in the mirror cast iron coating material, extract it to form a tight viscous cover and introduction into the melt of the solid modifier based on cerium, magnesium and Nickel, wherein prior to introduction into the melt of the solid modifier stand in the water, and smelting and the inoculation is carried out in the crucible induction furnace at the level of the molten cast iron is not above the level of the upper coil inductor furnace, and when the frequency of the inductor current 50-2400 Hz, and before backfilling the mirror cast iron coating material nominal power applied to the inductor furnace, reduced by 5-50%, after which the pig iron is poured into the ladle. 2. The method according to claim 1, characterized in that the filling of the coating material and the introduction of the modifier is carried out at a current frequency of the inductor 2400 Hz after reducing the nominal power applied to the inductor furnace, 5-15%. 3. The method according to claim 1, characterized in that the filling of the coating material and the introduction of the modifier is carried out at a frequency inductor current 500 Hz after reducing the nominal power applied to the inductor furnace, by 15-25%. 4. The method according to claim 1, characterized in that the filling of the coating material and the introduction of the modifier is carried out at a frequency inductor current 50 Hz after reducing the nominal power applied to the inductor furnace, by 40-50%. p> 5. The method according to claim 1, characterized in that the solid modifier is injected between the lining of the crucible and coating material.6. The method according to claim 1, characterized in that the time of introduction into the melt of the solid modifier is less than 5 seconds. 7. The method according to claim 1, characterized in that the solid modifier is administered in the amount of 1.0 to 1.5% by weight of modified liquid iron. 8. The method according to claim 1, characterized in that the introduction of solid modifier in the molten iron poured cover material. 9. The method according to claim 1, characterized in that the coating material using powder fluspirilene "Barrier".
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||