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US 4,053,303 AGranted
Method of carbothermically producing aluminum-silicon alloys
AssigneeAluminum Company of America
InventorsC. Norman Cochran, Subodh K. Das, Richard A. Milito
Life of this patent
Estimating the term…
Abstract
Aluminum-silicon alloys are formed by bringing a mix containing sources of alumina, silica and carbon to a temperature in the range of 1500.degree. and 1600.degree. C to form silicon carbide and carbon monoxide. The mix containing the silicon carbide is then brought to a temperature in the range of 1600.degree. to 1900.degree. C to form aluminum oxycarbide and carbon monoxide. Thereafter, the mix containing the silicon carbide and aluminum oxycarbide is brought to a temperature in the range of 1950.degree. to 2200.degree. C to produce an aluminum-silicon alloy.
Claims25
A method of carbothermically producing an aluminum-silicon alloy from alumina and silica bearing materials, the method comprising:
- a. bringing a mix containing sources of alumina, silica and carbon to a temperature in the range of 1500.degree. to 1600.degree. C. to form silicon carbide and carbon monoxide;
- b. bringing said mix containing said silicon carbide to a temperature in the range of 1600.degree. to 1900.degree. C. to form aluminum oxycarbide and carbon monoxide;
- c. bringing said silicon carbide and said aluminum oxycarbide to a temperature in the range of 1950.degree. to 2200.degree. C. to form said aluminum-silicon alloy;
- d. removing said carbon monoxide formed in step (a) without its passing through materials in steps (b) and (c);
- and
- e. removing said carbon monoxide formed in step (b) without its passing through materials in step (c).
3 more elements
A method of carbothermically producing an aluminum-silicon alloy from alumina and silica bearing materials, the method comprising:
- a. providing alumina and silica bearing materials and carbon in a mix, the weight ratio of silica to alumina in the mix being in the range of 0.15 to 1.1, the mix containing 15 to 30 wt.% carbon, the weight ratio being provided by combining an alumina poor ore with an alumina rich ore;
- b. reacting said mix at a temperature in the range of 1500.degree. to 1600.degree. C. to form silicon carbide and carbon monoxide;
- c. reacting said mix containing said silicon carbide in a second zone at a temperature in the range of 1600.degree. to 1900.degree. C. to form aluminum oxycarbide and carbon monoxide;
- d. reacting said silicon carbide and said aluminum oxycarbide at a temperature in the range of 1950.degree. to 2200.degree. C. to form said aluminum-silicon alloy;
- e. removing said carbon monoxide formed in step (b) without its passing through materials in steps (c) and (d);
- and
- f. removing said carbon monoxide formed in step (c) without its passing through materials present in step (d).
4 more elements
A method of carbothermically producing an aluminum-silicon alloy from alumina and silica bearing materials in a furnace, the method comprising:
- a. providing a mix containing sources of alumina, silica and carbon in a first zone in the furnace having a temperature in the range of 1500.degree. to 1600.degree. C. to form silicon carbide and carbon monoxide, the mix containing carbon in the range of 15 to 30 wt.% for reduction purposes;
- b. providing said mix containing said silicon carbide in a second zone having a temperature in the range of 1600.degree. to 1900.degree. C. to form aluminum oxycarbide and carbon monoxide;
- c. providing said silicon carbide and said aluminum oxycarbide in a third zone having a temperature in the range of 1950.degree. to 2200.degree. C. to form the aluminum-silicon alloy, the zones being heated by burning a source of carbon and a source of oxygen;
- d. removing the carbon monoxide formed in step (a) without its passing through materials in steps (b) and (c);
- and
- e. removing carbon monoxide formed in step (b) without its passing through materials in step (c).
3 more elements
A method of carbothermically producing an aluminum-silicon alloy from alumina and silica bearing materials in a furnace the method comprising:
- a. providing a mix containing sources of alumina, silica and carbon in a first zone in the furnace having a temperature in the range of 1500.degree. to 1600.degree. C. to form silicon carbide and carbon monoxide, the mix containing carbon in the range of 15 to 30 wt.% for reduction purposes;
- b. adding to said first zone, carbon and air in an amount sufficient to maintain said zone in the temperature range of 1500.degree. to 1600.degree. C.;
- c. providing said mix containing said silicon carbide in a second zone having a temperature in the range of 1600.degree. to 1900.degree. C. to form aluminum oxycarbide and carbon monoxide;
- d. adding to said second zone, carbon and air in an amount sufficient to maintain said zone in the temperature range of 1600.degree. to 1900.degree. C.;
- e. providing said silicon carbide and said aluminum oxycarbide in a third zone having a temperature in the range of 1950.degree. to 2200.degree. C. to form aluminum-silicon alloy;
- f. adding to said third zone carbon and substantially pure oxygen in an amount sufficient to maintain said zone in the temperature range of 1950.degree. to 2200.degree. C.;
- g. removing gases resulting from heating and reducing in steps (a) and (b) without such gases passing through materials in steps (c) and (e);
- and
- h. removing gases resulting from heating and reducing in steps (c) and (d) without such gases passing through materials in step (e).
6 more elements
A method of carbothermically producing an aluminum-silicon alloy from alumina and silica bearing materials in a furnace the method comprising:
- a. providing a mix containing sources of alumina, silica and carbon in a first zone in the furnace having a temperature in the range of 1500.degree. to 1600.degree. C. to form silicon carbide and carbon monoxide, the mix containing carbon in the range of 15 to 30 wt.% for reduction purposes and having silica to alumina in a weight ratio therein in the range of 0.15 to 1.1, the ratio being provided by adjusting the amount of either the alumina or silica in said materials;
- b. adding to said first zone, carbon mixed with air in an amount sufficient to maintain said zone in the temperature range of 1500.degree. to 1600.degree. C.;
- c. providing said mix containing said silicon carbide in a second zone having a temperature in the range of 1600.degree. to 1900.degree. C. to form aluminum oxycarbide and carbon monoxide;
- d. adding to said second zone, carbon mixed with air in an amount sufficient to maintain said zone in the temperature range of 1600.degree. to 1900.degree. C.;
- e. providing said silicon carbide and said aluminum oxycarbide in a third zone having a temperature in the range of 1950.degree. to 2200.degree. C. to form aluminum-silicon alloy;
- f. adding to said third zone, carbon mixed with substantially pure oxygen in an amount sufficient to maintain said zone in the temperature range of 1950.degree. to 2200.degree. C.;
- g. removing gases resulting from heating and reducing in steps (a) and (b) without such gases passing through materials in steps (c) and (e);
- and
- h. removing gases resulting from heating and reducing in steps (c) and (d) without such gases passing through materials in step (e).
6 more elements
Dependencies are inferred from the claim text.