Cast iron alloying with vanadium |
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IPC classes for russian patent Cast iron alloying with vanadium (RU 2520929):
Method of iron modification / 2515160
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.
 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.
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.
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FIELD: metallurgy. SUBSTANCE: invention relates to ferrous metallurgy and foundry, particularly, to improvement of properties of cast iron used for production of parts operated under variable-sign loads. In compliance with this invention, vanadium compound is reduced in cast iron melt under flux ply in the presence of reducer. Vanadium pentoxide (V2O5) is used as said vanadium compound. Ferrosilicon (FS75) is used as said reducer. Note here that vanadium is introduced into cast iron by chemical dispersion at feed to melt surface of the mix containing 30% of V2O5 , 20% of FS75 and 50% of CaO. EFFECT: production of high-strength cast iron with ferrite metal base obtained by introduction of vanadium in fine disperse form. 1 ex
The invention relates to a method of alloying iron-carbon alloys. The objective of the invention is to increase the doping efficiency at higher strength cast irons by introducing vanadium in a highly dispersed state in the form of separate clusters of atoms. The invention can be applied in producing high-strength cast iron with spherical graphite, the complex of physical-mechanical and technological properties of a unique material. Use it for critical components operating in alternating loads, in some cases is preferred (crankshafts, gears, connecting rods, etc.) the necessary combination of strength and ductility is achieved due to the complexity of the metallic base alloy transition from pearlite to ferritic-martensitic or banana-austenitic structure. However, this approach reduces the effect of the main advantages of cast iron before steels - technology. The results of a comprehensive study of strength and fracture toughness of cast iron with spherical graphite showed that the provision of high quality material due to the large number of factors. But the most important factor you need to consider the layout of the metallic base. High values of fracture toughness (crack resistance) is achieved when the ferritic structure is re. In this case, in conditions of high ductility is ensured by the commitment of the solid body to carry out the most effective channels of stress relaxation. The results of the study of the specificity of plastic flow crack nucleation and fracture under conditions of cyclic loading showed that for ductile materials is very favourable to the introduction of impurities forming a stable chemical compounds that impede grain boundary sliding and deformation localization, form in the alloy fine thermostable structure. The introduction of dispersed inclusions in ferritic metal base cast iron increases the strength characteristics of the material. One of the most effective hardening phases are the inclusion of vanadium carbide. Compared with traditional inclusions of chromium carbide they are better dispersed in the iron-carbon alloy, and embedded vanadium is completely converted into vanadium carbide. Carbides of vanadium, being more rigid material than the carbides of chromium, more effectively provide dispersion hardening of the ferritic matrix. But the usual method of alloying with vanadium subsequent homogenizing annealing provides the equilibrium size of the carbides of vanadium 30 nm. Developed by the authors method of chemical dispersion in the doping range of metallic alloys [1] has allowed for ucati inclusion of the alloying element is significantly below the equilibrium. The objective of the invention is to implement the process of chemical dispersion of vanadium in iron-carbon alloy to ensure complete reaction of the recovery of the alloying element and prevent its oxidation by air oxygen. Proper implementation of the process is achieved by using as the source of vanadium compounds patikis V2O5, which has a relatively low melting temperature is 680°C (VO - 1830°C, V2O3- 1970°C, V2O4- 1530°C), and as a reducing agent to apply the silicon in the form of ferrosilicon. This method of doping allows to realize the effect of chemical dispersion without technical difficulties and high costs of the process. Use as a reductant aluminum or carbon leads to higher process or the need to increase the temperature. The example implementation. The original cast iron composition C - 3.31; Si - 2.30; Mn - 1.00; S - 0.03; P≤0.03 (wt.%) - melted in an induction furnace grade VCI 1-4/1,78. Spheroidizing modification was carried out according to the method of [1], which, along with high dispersion of magnesium provides high deoxidation and desulfurization melt. The residual content of sulfur and oxygen in the iron was not more than 0.001%. Enter vanadium in the melt was carried out in two ways: normal with use ligatures Fudai input to the surface of the melt mixture of 30% V 2O5+20%FS+50% CaO. To obtain a ferritic structure, the molten iron after treatment was poured into a heated form. The obtained samples were subjected to chemical metallographic analysis. The results of the tests showed that the vanadium content in the samples (after treatment with vanadium and chemically dispersed vanadium) in the range of 0.1-1.1%, regulated by the amount entered additives. The size of the inclusions vanadium at its input in the form of ferrovanadium was 30 nm after homogenizing annealing (up to annealing in melted state, the size of the inclusions was much higher than this value). When chemical dispersion could be obtained include vanadium significantly smaller in melted condition. The results of the mechanical properties of the samples are presented in [2]. The advantages of the proposed method. The proposed method of doping allows no additional cost and technical difficulties to obtain finely dispersed inclusions of vanadium in iron, which, as shown in [2], contributing to a sharp increase in the strength characteristics of the material. Literature 1. The method of inoculation of cast iron. Patent No. 2058396 of the Russian Federation. 2. Shakhnazarov T.A., Tokhtarov Y.A. Dissipative processes in cyclic hardening of nodular cast iron. The metals. 2006, No. 4, p.54-61. Method of alloying h is guna vanadium, including the recovery of vanadium compounds in the melt of cast iron under a layer of flux, in which the vanadium compounds used vanadium pentoxide (V2O5), and as a reductant ferrosilicon (FS), and the vanadium is introduced into the cast iron by the method of chemical dispersion is fed to the surface of the melt mixture containing 30% V2O5, 20% PC and 50% CaO.
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