EP0283517B1 - Verfahren zur herstellung von aluminosilikonlegierungen mit 2-22 gewichtsprozent silizium - Google Patents

Verfahren zur herstellung von aluminosilikonlegierungen mit 2-22 gewichtsprozent silizium Download PDF

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Publication number
EP0283517B1
EP0283517B1 EP86907017A EP86907017A EP0283517B1 EP 0283517 B1 EP0283517 B1 EP 0283517B1 EP 86907017 A EP86907017 A EP 86907017A EP 86907017 A EP86907017 A EP 86907017A EP 0283517 B1 EP0283517 B1 EP 0283517B1
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EP
European Patent Office
Prior art keywords
silicon
fraction
crystalline silicon
alloy
melt
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP86907017A
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German (de)
English (en)
French (fr)
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EP0283517A1 (de
EP0283517A4 (de
Inventor
Viktor Semenovich Shusterov
Vadim Petrovich Ivchenkov
Vladimir Anatolievich Gorbunov
Anatoly Nikolaevich Malenkikh
Vladimir Nikolaevich Senin
Elena Leonidovna Lukina
Vladimir Vladimirovich Volkov
Fedor Konstantinovich Teplyakov
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.)
VSESOJUZNY NAUCHNO-ISSLEDOVATELSKY I PROEKTNY INSTITUT ALJUMINIEVOI MAGNIEVOI I ELEKTRODNOI PROMYSHLENNOSTI
Original Assignee
VSESOJUZNY NAUCHNO-ISSLEDOVATELSKY I PROEKTNY INSTITUT ALJUMINIEVOI MAGNIEVOI I ELEKTRODNOI PROMYSHLENNOSTI
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Publication of EP0283517A1 publication Critical patent/EP0283517A1/de
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Classifications

    • CCHEMISTRY; METALLURGY
    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C1/00Making non-ferrous alloys
    • C22C1/02Making non-ferrous alloys by melting
    • C22C1/026Alloys based on aluminium

Definitions

  • the invention relates to the field of metallurgy of non-ferrous metals and alloys, and in particular to processes for the production of aluminum-silicon alloy with a silicon content of 2 to 22 mass%.
  • a method for producing an aluminum-silicon alloy with a silicon content of 2 to 22% by mass which consists in exposing alumina and silicon to separate comminution.
  • a feed material is prepared from the carbon-containing material and the comminuted alumina and the comminuted silicon, the components mentioned being used in calculated amounts.
  • briquettes are made from the feed, which are placed in an ore reduction electro furnace.
  • primary aluminum-silicon alloy is obtained.
  • the alloy produced from non-metallic inclusions is refined and processed into aluminum-silicon construction alloys (I.A. Troitsky, V.A. Zheleznov "Metallurgia aluminiya”, published I977, Verlag “Metallurgiya”, Moscow, pp. 368-375).
  • Disadvantages of the process mentioned include the low degree of utilization of silicon and the low quality of the alloy produced as a result of an increased content of non-metallic inclusions therein.
  • the process control according to the above-mentioned process is associated with a high degree of slag formation and with substantial heat losses for the slag formation (up to 10%).
  • the process consists of several stages and requires a large amount of electricity.
  • a method for producing aluminum-silicon alloy containing silicon is known from 2 to 22% by mass, which is that the separation of the crushed crystalline sicilium into fractions with the decrease of a fraction of 20 to 50 mm and a fraction of 0.3 to 1.0 mm (the last fraction is thrown away) and the crystalline silicon of the fraction of 20 to 50 mm is dissolved in the liquid aluminum at a temperature of 780 to 820 ° C. in a radiation furnace with mixing with the accumulation of aluminum-silicon melt.
  • MVAltman, AALebedev, MVChukhov "Plavka i litje legkikh splavov" / melting and casting of light alloys published I969, Verlag "Metallurgiya", Moscow, pp. 270-27I).
  • the described method ensures that an increased degree of utilization of silicon is achieved and that an alloy of good quality is produced as a result of a reduced content of non-metallic inclusions in it (aluminum oxide and hydrogen).
  • this process enables the degree of slag formation to be reduced.
  • the process is technologically easy to carry out and does not require a large amount of electricity.
  • the crystalline silicon of the fraction from 0.3 to 1.0 mm is not used for the production of the aluminum-silicon alloy, which causes a loss of deficient raw material.
  • the invention has for its object to change the conditions of the process control of the dissolution of the crystalline silicon in the process for the production of aluminum-silicon alloy with a silicon content of 2 to 22 mass% so that the possibility is created of crystalline silicon Fraction of 0.3 to 1.0 mm to use and thereby to avoid the loss of deficient raw material and to improve the quality of the alloy produced.
  • the method according to the invention for the production of aluminum-silicon alloy with a silicon content of 2 to 22 mass%, which separates the crushed crystalline silicon into fractions with the removal of a fraction of 20 to 50 mm and a fraction of 0.3 to 1.0 mm, the dissolution of the crystalline silicon of the fraction of 20 to 50 mm in liquid aluminum at a temperature of 780 to 820 ° C with mixing in a radiation furnace with the accumulation of aluminum Silicon melt provides, according to the invention, simultaneously with the dissolution of the crystalline silicon of the fraction from 20 to 50 mm, the crystalline silicon of the fraction from 0.3 to 1.0 mm in an amount of 3 to 10%, based on introduces the total mass of the crystalline silicon feed under the melt plane with an inert gas jet.
  • the stated object is also achieved in that in the process according to the invention (its second variant) for producing an aluminum-silicon alloy with a silicon content of 2 to 22% by mass, the separation of the comminuted crystalline silicon into fractions with the decrease a fraction of 20 to 50 mm and a fraction of 0.3 to I, 0 mm, the dissolution of the crystalline silicon of the fraction of 20 to 50 mm in liquid aluminum at a temperature of 780 to 820 ° C with mixing in a blast furnace with The occurrence of an aluminum-silicon melt provides, according to the invention, the dissolution of the crystalline silicon of the fraction from 20 to 50 mm together with the crystalline silicon of the fraction from 0.3 to 1.0 mm with a mass ratio of the fractions of 80-85: 20- I5 is carried out, taking the crystalline silicon fraction from 0.3 to 1.0 mm before dissolving with barium chloride and a flux based on sodium - and Potassium chlorides at a mass ratio of the crystalline silicon of the fraction of 0.3 to 1.0
  • the method according to the invention makes it possible to use the crystalline silicon of the fraction from 0.3 to 1.0 mm, thereby avoiding the loss of deficient raw material.
  • the method according to the invention also makes it possible to produce an alloy with a better quality due to a lower content of non-metallic inclusions therein (aluminum oxide and hydrogen).
  • the increase in the residence time of the fine Silicon fraction in the melt volume reached which means that the time for the fine fraction to dissolve in the melt is sufficient before it manages to float to the surface.
  • the inert gas also promotes the removal of non-metallic inclusions (hydrogen and aluminum oxide) from the melt when it reaches the melt.
  • the crystalline silicon fraction of 20 to 50 mm when crushed has an average yield of 95% and the fraction of 0.3 to 1.0 mm has an average yield of 4.5%.
  • the fraction from 0.3 to 1.0 mm was not used for the production of an aluminum-silicon alloy, which caused the loss of deficient raw material.
  • the present invention proposes a method for producing an aluminum-silicon alloy using the fraction from 0.3 to 1.0 mm.
  • the introduction of the crystalline silicon of the fraction from 0.3 to 1.0 mm in an amount below 3%, based on the total mass of the silicon feed, with the inert gas jet leads to a low degree of utilization of equipment , and the introduction of the said fraction in an amount over 10%, based on the total mass of the silicon feed, leads to a large consumption of inert carrier gas.
  • the fraction of crystalline silicon is from 20 to 50 mm and the fraction from 0.3 to 1.0 mm with their mass ratio equal to 80 to 85:20 to I5 used.
  • the use of the crystalline silicon of the fraction from 0.3 to 1.0 mm in an amount above the upper limit in the above ratio is not appropriate because it leads to the need for the amount of barium chloride which is pressed together with the fraction of 0.3 to 1.0 mm and used with the flux to enlarge, which in turn leads to an undesirable increase in the viscosity of the melt.
  • the use of the crystalline silicon fraction from 0.3 to 1.0 mm in an amount below the lower limits in the stated ratio is not recommended, since the effectiveness of the process control is noticeably impaired.
  • the crystalline silicon of the fraction from 0.3 to 1.0 mm is pressed together with barium chloride and a flux in a mass ratio equal to (7: I) to (2: I to 3).
  • the upper limit for the barium chloride and flux in the ratio mentioned is determined by the fact that a further increase in the content of barium chloride and flux leads to an undesirable increase in the viscosity of the melt and to an unproductive consumption of flux.
  • the method according to the invention for producing aluminum-silicon alloy with a silicon content of 2 to 22% by mass is carried out as follows.
  • the crushed crystalline silicon is fractionated in fractions from 20 to 50 mm and from 0.3 to 1.0 mm, after which the fraction from 20 to 50 mm is placed in a radiation oven. Then the required amount of liquid aluminum is poured into the furnace at a temperature of 780 to 820 ° C.
  • the crystalline silicon of the fraction of 20 to 50 mm is dissolved in the liquid aluminum at the temperature mentioned and with mixing with the formation of an aluminum-silicon melt.
  • Mixing can be carried out, for example, using centrifugal pumps from "Carborundum” (USA), gas dynamopumps and electromagnetic mixing devices (ADAndreev, VBGogin, GSMakarov "High-performance melting of aluminum alloys", published I980, "Metallurgia", Moscow, S. 89-95).
  • the crystalline silicon of the fraction from 0.3 to 1.0 mm in an amount of 3 to 10%, based on the total mass of the silicon, with one jet of inert gas, for example nitrogen, argon, introduced under the melt plane.
  • inert gas for example nitrogen, argon
  • the formation of the jet of the inert gas in a mixture with the crystalline silicon of the fraction from 0.3 to 1.0 mm takes place in a fluidized bed apparatus.
  • the degree of skill of the alloy to be produced is determined by the results of a rapid analysis according to the content of basic components of the alloy and the admixtures, after which the finished alloy is cast in molds.
  • the second variant is the method according to the invention for the production of aluminum-silicon alloy with a silicon content of 2 to 22 mass% as follows.
  • the crushed crystalline silicon is fractionated in fractions from 20 to 50 mm and from 0.3 to 1.0 mm. Thereafter, the crystalline silicon of the fraction from 0.3 to 1.0 mm with barium chloride (weighting agent) and with a flux based on sodium and potassium chloride with a mass ratio of crystalline silicon to barium chloride and flux equal to 7: I to 2 : I-3 pressed together.
  • a flux for example, a mixture can be used which is composed of 52 to 57 mass% NaCl, 30 to 35 mass% KCl and 10 to 15 mass% Na2SiF6. Then the crystalline silicon of the fraction from 20 to 50 mm and the produced compressed material containing the silicon fraction from 0.3 to 1.0 mm are placed in the radiation furnace.
  • the mass ratio of the silicon fraction from 20 to 50 mm to the silicon fraction from 0.3 to 1.0 mm is 80-85: 20: I5.
  • the required amount of liquid aluminum is poured into the furnace at a temperature of 780 to 820 ° C. and the crystalline silicon of the two fractions is dissolved together in the liquid aluminum at the temperature mentioned and mixed with the formation of an aluminum-silicon Melt through.
  • the crystalline silicon of the fraction from 0.3 to 1.0 mm manages to dissolve in the melt volume due to the increase in its residence time.
  • the mixing mentioned is carried out in a similar manner to that described in the first variant of the process.
  • the level of skill of the alloy to be produced is determined by the results of a rapid analysis according to the content of basic components of the alloy and the admixtures, after which the finished alloy is cast in molds.
  • Example I (first variant of the method according to the invention.
  • the crushed crystalline silicon is fractionated in fractions from 20 to 50 mm and from 0.3 to 1.0 mm, after which the fraction from 20 to 50 mm in an amount of 2650 kg is drawn into a blasting furnace with a capacity of 25000 kg on the liquid metal. Then 22,250 kg of the liquid aluminum are poured into the furnace at a temperature of 800.degree.
  • the crystalline silicon of the fraction of 20 to 50 mm is dissolved in the liquid aluminum at the temperature mentioned and with mixing with the formation of an aluminum-silicon melt. Mixing takes place using an electromagnetic mixing device.
  • the crystalline silicon of the fraction from 0.3 to 1.0 mm in an amount of 270 kg (10%, based on the total mass of the silicon feed) with a Nitrogen jet introduced below the melt level.
  • the calculated amount of silicon in the melt is II.7% by mass.
  • the skill level of the alloy is determined by the results of a rapid analysis of the content of basic components of the alloy and the admixtures, after which the finished alloy with a silicon content of II.4% by mass is poured into molds.
  • the crushed crystalline silicon is fractionated in fractions from 20 to 50 mm and from 0.3 to 1.0 mm. Then the crystalline silicon of the fraction from 0.3 to 1.0 mm in an amount of 584 kg is pressed together with I66.8 kg barium chloride and 250.2 kg flux (the mass ratio of the silicon fraction with the barium chloride and the flux is 7: 2 or 3).
  • the flux is a mixture composed of 52% by mass NaCl, 34% by mass KCl and 14% by mass Na2SiF6. Then in the blasting furnace with a capacity of 25000 kg, based on the liquid metal, crystalline silicon of the fraction of 20 to 50 mm in an amount of 2336 kg and the produced compressed material, which contains the silicon fraction from 0.3 to 1.0 mm.
  • the mass ratio of the silicon fraction from 20 to 50 mm to the silicon fraction from 0.3 to 1.0 mm is 80:20.
  • the calculated amount of silicon in the alloy is II.7 mass%.
  • the silicon of the fraction from 0.3 to 1.0 mm manages to dissolve due to the increase in its residence time in the melting volume.
  • the aforementioned mixing is carried out using an electromagnetic mixing device.
  • the degree of skill of the alloy is determined by the results of a rapid analysis of the content of basic components of the alloy and the admixtures, after which the finished alloy with a silicon content of II.4% by mass is poured into molds.
  • the degree of utilization of the crystalline silicon of the fraction from 0.3 to 1.0 mm was determined as follows for both variants of the method according to the invention.
  • the degree of utilization of the crystalline silicon of the fraction from 0.3 to 1.0 mm was calculated using the following formula: wherein C I content of silicon in the alloy made using the crystalline silicon fraction from 20 to 50 mm, mass%. C2 - silicon content in the alloy, which was produced using the crystalline silicon fraction from 20 to 50 mm and from 0.3 to I, 0 mm, mass%.
  • the method according to the invention makes it possible to use the crystalline silicon of the fraction from 0.3 to 1.0 mm, which excludes the loss of deficient raw material.
  • the high degree of utilization of the silicon of the fine fraction mentioned is guaranteed, this degree is practically the same as the degree of utilization of the silicon of the fraction from 20 to 50 mm according to the known method.
  • the proposed invention can be used in the field of metallurgy of non-ferrous metals and alloys for producing an aluminum-silicon alloy with a silicon content of 2 to 22% by mass.
  • the alloy mentioned can be used for the production of molded castings for the needs of the motor vehicle, auto and tractor industries and for the production of consumer goods.

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Silicon Compounds (AREA)
  • Manufacture And Refinement Of Metals (AREA)
EP86907017A 1986-09-29 1986-09-29 Verfahren zur herstellung von aluminosilikonlegierungen mit 2-22 gewichtsprozent silizium Expired - Lifetime EP0283517B1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/SU1986/000094 WO1988002409A1 (en) 1986-09-29 1986-09-29 Method of obtaining aluminosilicon alloy containing 2-22 per cent by weight of silicon

Publications (3)

Publication Number Publication Date
EP0283517A1 EP0283517A1 (de) 1988-09-28
EP0283517A4 EP0283517A4 (de) 1989-02-06
EP0283517B1 true EP0283517B1 (de) 1992-03-18

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ID=21617037

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86907017A Expired - Lifetime EP0283517B1 (de) 1986-09-29 1986-09-29 Verfahren zur herstellung von aluminosilikonlegierungen mit 2-22 gewichtsprozent silizium

Country Status (10)

Country Link
EP (1) EP0283517B1 (ro)
JP (1) JPH01501008A (ro)
CN (1) CN1011045B (ro)
AU (1) AU584771B2 (ro)
DD (1) DD260521A1 (ro)
DE (1) DE3684480D1 (ro)
IN (1) IN166791B (ro)
NO (1) NO882211L (ro)
RO (1) RO101829B1 (ro)
WO (1) WO1988002409A1 (ro)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2814757B1 (fr) * 2000-10-02 2003-07-11 Invensil Elaboration d'alliages de type aluminium-silicium
CN103773978A (zh) * 2014-01-27 2014-05-07 中信戴卡股份有限公司 铝硅合金制备方法
CN104617276B (zh) * 2015-02-10 2018-03-30 南开大学 锂离子二次电池多孔硅/碳复合负极材料及其制备方法
CN104674031A (zh) * 2015-03-02 2015-06-03 天津立中合金集团有限公司 铝合金熔炼过程中工业硅的新型加入方法

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4046558A (en) * 1976-11-22 1977-09-06 Aluminum Company Of America Method for the production of aluminum-silicon alloys
US4053303A (en) * 1976-12-06 1977-10-11 Aluminum Company Of America Method of carbothermically producing aluminum-silicon alloys
IT1152984B (it) * 1982-06-22 1987-01-14 Samim Soc Azionaria Minero Met Procedimento per la produzione di una lega alluminio silicio da concentrati contenenti gli ossidi corrispondenti anche chimicamente tra loro e/o con altri ossidi metallici
SE450583B (sv) * 1982-10-22 1987-07-06 Skf Steel Eng Ab Sett att framstella aluminium-kisel-legeringar

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Publication number Publication date
DD260521A1 (de) 1988-09-28
CN87102446A (zh) 1988-10-12
AU584771B2 (en) 1989-06-01
RO101829B1 (en) 1992-11-02
EP0283517A1 (de) 1988-09-28
CN1011045B (zh) 1991-01-02
JPH01501008A (ja) 1989-04-06
NO882211D0 (no) 1988-05-20
AU6726487A (en) 1988-04-21
IN166791B (ro) 1990-07-21
NO882211L (no) 1988-05-20
EP0283517A4 (de) 1989-02-06
WO1988002409A1 (en) 1988-04-07
DE3684480D1 (de) 1992-04-23

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