US3861888A - Use of CO{HD 2 {B in argon-oxygen refining of molten metal - Google Patents
Use of CO{HD 2 {B in argon-oxygen refining of molten metal Download PDFInfo
- Publication number
- US3861888A US3861888A US374635A US37463573A US3861888A US 3861888 A US3861888 A US 3861888A US 374635 A US374635 A US 374635A US 37463573 A US37463573 A US 37463573A US 3861888 A US3861888 A US 3861888A
- Authority
- US
- United States
- Prior art keywords
- decarburization
- carbon
- flow rate
- argon
- oxygen
- 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
Links
- 229910052751 metal Inorganic materials 0.000 title claims description 28
- 239000002184 metal Substances 0.000 title claims description 27
- 238000007670 refining Methods 0.000 title abstract description 14
- VVTSZOCINPYFDP-UHFFFAOYSA-N [O].[Ar] Chemical compound [O].[Ar] VVTSZOCINPYFDP-UHFFFAOYSA-N 0.000 title abstract description 12
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 63
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 60
- 238000005261 decarburization Methods 0.000 claims abstract description 47
- 239000000155 melt Substances 0.000 claims abstract description 33
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 31
- 239000010959 steel Substances 0.000 claims abstract description 31
- 239000007789 gas Substances 0.000 claims abstract description 26
- 239000011261 inert gas Substances 0.000 claims description 14
- 238000007664 blowing Methods 0.000 claims description 10
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 abstract description 32
- 229910052760 oxygen Inorganic materials 0.000 abstract description 24
- 239000001301 oxygen Substances 0.000 abstract description 23
- 238000000034 method Methods 0.000 abstract description 22
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 abstract description 21
- 239000000203 mixture Substances 0.000 abstract description 19
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 abstract description 16
- 229910052786 argon Inorganic materials 0.000 abstract description 16
- 229910001220 stainless steel Inorganic materials 0.000 abstract description 11
- 229910002092 carbon dioxide Inorganic materials 0.000 abstract description 8
- 239000010935 stainless steel Substances 0.000 abstract description 7
- 238000002347 injection Methods 0.000 abstract description 6
- 239000007924 injection Substances 0.000 abstract description 6
- 239000001569 carbon dioxide Substances 0.000 abstract description 4
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 10
- 229910052804 chromium Inorganic materials 0.000 description 10
- 239000011651 chromium Substances 0.000 description 10
- 229910002091 carbon monoxide Inorganic materials 0.000 description 8
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 7
- 238000007254 oxidation reaction Methods 0.000 description 7
- 230000003647 oxidation Effects 0.000 description 6
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 229910045601 alloy Inorganic materials 0.000 description 3
- 239000000956 alloy Substances 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 229910002090 carbon oxide Inorganic materials 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 229910052743 krypton Inorganic materials 0.000 description 2
- DNNSSWSSYDEUBZ-UHFFFAOYSA-N krypton atom Chemical compound [Kr] DNNSSWSSYDEUBZ-UHFFFAOYSA-N 0.000 description 2
- 229910052754 neon Inorganic materials 0.000 description 2
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 239000002893 slag Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- -1 such as Substances 0.000 description 2
- 229910052724 xenon Inorganic materials 0.000 description 2
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 2
- CNJLMVZFWLNOEP-UHFFFAOYSA-N 4,7,7-trimethylbicyclo[4.1.0]heptan-5-one Chemical compound O=C1C(C)CCC2C(C)(C)C12 CNJLMVZFWLNOEP-UHFFFAOYSA-N 0.000 description 1
- 229910000640 Fe alloy Inorganic materials 0.000 description 1
- 229910000604 Ferrochrome Inorganic materials 0.000 description 1
- 208000036366 Sensation of pressure Diseases 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000010924 continuous production Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007717 exclusion Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 229910044991 metal oxide Inorganic materials 0.000 description 1
- 150000004706 metal oxides Chemical class 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- FXNGWBDIVIGISM-UHFFFAOYSA-N methylidynechromium Chemical compound [Cr]#[C] FXNGWBDIVIGISM-UHFFFAOYSA-N 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 238000004886 process control Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 238000009628 steelmaking Methods 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
Classifications
-
- 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
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/068—Decarburising
- C21C7/0685—Decarburising of stainless steel
Definitions
- This invention relates, in general, to a method for decarburizing metals and alloys, and more specifically, to an improvement in the argon-oxygen decarburization of stainless steels.
- the AOD process is a duplex process, particularly useful for refining stainless steels without substantial loss of chromium.
- the basic AOD process is disclosed in Krivsky, US. Pat. No. 3,252,790 and an improvement thereon relating to programmed blowing is disclosed in Nelson et al., US. Pat. No. 3,046,107.
- the process comprises melting the alloy (substantially at the desired composition with respect to metallics) in an arc furnace, and transferring the molten metal, after it has been deslagged, to a refining vessel wherein it is decarburized by subsurface blowing with an inert gasoxygen mixture (in commerical practice most frequently an argon-oxygen mixture), the argon being present in order to reduce the partial pressure of carbon monoxide in the gas in contact with the melt.
- the molten metal is thereafter reduced, finished and tapped into a teeming ladle.
- a suitable refining vessel is disclosed by Saccomano and Ellis in US. Pat. No. 3,724,830.
- AOD practice relates to shortening the overall process time.
- the chemical reactions of steel refining are, for the most part, oxidation reactions which generate heat; the metal bath temperature being established at the point where the heat generated in the bath equals the heat lost by the refining vessel through radiation and convection.
- the faster heat is generated the higher the bath temperature at the point of thermal equilibrium.
- the speed of decarburization can be increased by increasing the process gas flow rates, but only at the expense of higher bath temperature and increased refractory wear of the furnace lining. Consequently, there is a need for increasing the speed of decarburization in an AOD process without exceeding a predetermined temperature limit beyond which the effective life of the furnace refractory is considerably shortened, generally about 3,100F.
- Periodic addition of scrap as a coolant is a commonly accepted procedure for maintaining the bath temperature within the desired operating range.
- the logistics of supplying scrap at the furnace at the exact time it is needed and the difficulty of keeping stainless scrap segregated by type often precludes its use.
- scrap cools the metal bath discontinuously, such that the addition of scrap with its attendant sudden drop in bath temperature frequently causes exccssive metallic oxidation for the period of time during which the bath is cooled below an efficient decarburization temperature.
- the present invention comprises: in a process for decarburizing a mass of chromiumcontaining molten steel characterized by the subsurface injection of oxygen and at least one inert gas selected from the group consisting of helium, neon, krypton, argon, xenon and nitrogen, into said mass of said molten steel, wherein at least a portion of said oxygen reacts with the carbon in said molten steel to form a volatile carbon oxide, comprising a first phase of decarburization wherein the temperature of said molten steel is increased to the desired operating range; a second phase of decarburization wherein the carbon content of the molten steel is reduced to a predetermined value corresponding approximately to the carbon content of the melt in equilibrium with CO at a partial pressure of 1 atmosphere and at a temperature within said desired operating range; and a third phase of decarburization wherein the carbon content of the melt is reduced from said predetermined value
- decarburization refers to the lowering of the carbon content of the molten steel from any given level to any desired lower level by the injection of oxygen into the melt.
- mass is intended to mean a batch or heat of molten metal, as well as a changing mass as in a continuous process.
- chromium-containing molten steel as used herein is intended to comprise ferrous alloys containing about 340% chromium.
- the invention is predicated on the discovery that the injection of CO along with oxygen and an inert gas into the molten steel increases the carbon removal efficiency during decarburization.
- the caron removal efficiency is known to decrease as well.
- the carbon removal efficiency is increased and consequently, the absolute rate of carbon removal (i.e. the speed of decarburization) is also increased.
- the primary function of the inert gas in the inert gas-oxygen mixture is to lower the partial pressure of carbon monoxide in contact with the melt and thereby enhance carbon removal. Therefore, inasmuch as carbon monoxide is one of the decomposition products of CO in the melt, the increase in the carbon removal efficiency resulting from the present invention is truly surprising.
- the flow rate of CO in accordance with the relationship set forth above, is defined in terms of an upper limit in order to prevent an excess of CO from being injected into the melt and recarburizing the bath. It is calculated as follows: the maximum flow rate of carbon monoxide out of the vessel is related to the flow rate of argon by the following relationship:
- FCO maX FIP/l P
- P can be calculated from literature data (Electric Furnace Steelmaking, Vol. 11, Chapter 16, p. 95; Chipman, J., J.I.S.I., pp. 97-106, June, 1955; Schenck, I-I., et al., Stahleisen Sonderberichte, Special Report No. 7, Stahleisen mbh, Dusseldorf, 1966).
- the actual flow of carbon monoxide is F ZXF
- the difference between F and F must accommodate the additional carbon monoxide from the improved decarburization as well as that from dissociation'of carbon dioxide. The flow rate of carbon dioxide must therefore be less than the following amount in order to benefit the carbon removal efficiency.
- (cfm) t blowing time, (minutes) C,- carbon content of the melt at the start of the blow, (percent) C, carbon content of the melt at the end of the blow, (percent) T, metal bath temperature at the start of the blow,
- T; metal bath temperature at the end of the blow
- a three component gas mixture containing oxygen, CO and an inert gas may optionally be injected during said first and/or second phases of decarburization.
- the three component gas mixture may be effectively used during all three phases of decarburization, during the second or third phases of decarburization or only during said third phase.
- the preferred flow rates for each of the gases in the three phase mixture and the corresponding blow time are defined by the identical relationship previously set forth for phase 3 of decarburization. That is, equations (1), (2) and (3) define the preferred gas flow and blow time for both the second and third phases of decarburization.
- the flow rates of oxygen, argon and C0 are generally set at a fixed predetermined ratio and consequently the variables to be determined are the carbon content at the end of the blow and the blow time required. It is preferred that CO be used during said first phase to the exclusion of argon because it improves process control. Accordingly, mixtures of O and CO may be effectively used in ratios varying from 4:1 to 1:1.
- the remaining variables of time, temperature, flow and carbon content are preferably related by the following equations:
- the second blow period begins during which the ratio of argon to oxygen in the blowing gas mixture is increased to prevent the bath from overheating, and the carbon content of the melt is reduced to approximately the point where further decarburization can only be achieved at the expense of substantial chromium oxidation in the melt.
- the termination During the third phase of decarburization the furnace operator may wish to decarburize to C 0.05% while attaining a temperature 3,100F preparatory to finish the heat. The given conditions are thus changed to accomodate the additional argon which will be required to decarburize the melt to a level below 0.25% carbon.
- X 322 (Ci pi Cf)/V where V volume of oxygen (ft )/ton of metal Since X will vary depending upon carbon content of the melt, bath temperature and vessel characteristics, it must be determined empirically under the operating conditions of interest.
- an improvement in carbon removal efficiency is generally most desirable during the period when the steel is to be decarburized to a carbon level below that which is in equilibrium with CO at a partial pressure of one atmosphere; namely, during the third phase of decarburization.
- 6 beats of stainless steel were made in an 18 ton AOD vessel 4 heats being run as in conventional AOD practice with a 2 component (argon-oxygen) blowing mixture; the remaining 2 heats using a 3 component mixture including CO in accordance with the present invention.
- the measured gas flow rates, initial and final carbon contents and bath temperatures, and the resulting carbon removal efficiency are indicated in Table III.
- F total gas flow rate for the particular system 1.
- a process for decarburizing a chromiumcontaining molten steel characterized by the subhlOWlhg tlme, (mlhutes) surface injection of oxygen and at least one inert gas C1 Carbon Content of the melt at the Start Of the selected from the group consisting of helium, neon, ,(P
- a first phase of decarburization wherein the temperature of said molten steel is adjusted to the desired operating range
- a second phase of decarburization wherein the carbon content of the molten steel is reduced to a predetermined value corresponding approximately to the carbon content of the melt in equilibrium with CO at a partial pressure of 1 atmosphere and at a temperature within said desired operating range
- a third phase of decarburization wherein the carbon content of the melt is reduced from said predetermined value to approximately the desired carbon content of the molten steel
- T; metal bath temperature at the end of the blow
- T metal bath temperature at the end of the blow
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Priority Applications (14)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US374635A US3861888A (en) | 1973-06-28 | 1973-06-28 | Use of CO{HD 2 {B in argon-oxygen refining of molten metal |
| AU69443/74A AU6944374A (en) | 1973-06-28 | 1974-05-28 | Decarburisation of molten steel with o2, co2 and inert gases |
| BE145977A BE816970A (fr) | 1973-06-28 | 1974-06-27 | Perfectionnement a la decarburation d'une fonte du chrome au moyen d'oxygene et d'un gaz inerte |
| BR5267/74A BR7405267A (pt) | 1973-06-28 | 1974-06-27 | Aperfeicoamento no processo para a descarburacao de aco em fusao |
| DE19742430975 DE2430975C3 (de) | 1973-06-28 | 1974-06-27 | Verfahren zum Entkohlen einer chromhaltigen Stahlschmelze |
| DD179518A DD112468A5 (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| PL1974172235A PL88825B1 (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| SE7408502A SE7408502L (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| FI1978/74A FI197874A7 (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| FR7422449A FR2235198B1 (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| JP49072891A JPS5037611A (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| IL45137A IL45137A (en) | 1973-06-28 | 1974-06-27 | Argon-oxygen decarburization process for refining stainless steel by use of carbon dioxide |
| NO742347A NO742347L (enrdf_load_stackoverflow) | 1973-06-28 | 1974-06-27 | |
| US05/760,841 USRE29584E (en) | 1973-06-28 | 1977-01-21 | Use of CO2 in argon-oxygen refining of molten metal |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US374635A US3861888A (en) | 1973-06-28 | 1973-06-28 | Use of CO{HD 2 {B in argon-oxygen refining of molten metal |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US05/760,841 Reissue USRE29584E (en) | 1973-06-28 | 1977-01-21 | Use of CO2 in argon-oxygen refining of molten metal |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3861888A true US3861888A (en) | 1975-01-21 |
Family
ID=23477618
Family Applications (2)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US374635A Expired - Lifetime US3861888A (en) | 1973-06-28 | 1973-06-28 | Use of CO{HD 2 {B in argon-oxygen refining of molten metal |
| US05/760,841 Expired - Lifetime USRE29584E (en) | 1973-06-28 | 1977-01-21 | Use of CO2 in argon-oxygen refining of molten metal |
Family Applications After (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US05/760,841 Expired - Lifetime USRE29584E (en) | 1973-06-28 | 1977-01-21 | Use of CO2 in argon-oxygen refining of molten metal |
Country Status (12)
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4174212A (en) * | 1978-03-10 | 1979-11-13 | A. Finkl & Sons Co. | Method for the refining of steel |
| US4260415A (en) * | 1979-12-12 | 1981-04-07 | Allegheny Ludlum Steel Corporation | Decarburizing molten metal |
| US4321088A (en) * | 1978-05-11 | 1982-03-23 | Basf Aktiengesellschaft | Process for treating pig iron melts and steel melts or alloys |
| US4409028A (en) * | 1979-10-24 | 1983-10-11 | Moore William H | Process for producing cast iron |
| US4490172A (en) * | 1979-06-29 | 1984-12-25 | Moore William H | Method of melting and refining steel and other ferrous alloys |
| US4746361A (en) * | 1987-04-03 | 1988-05-24 | Inland Steel Company | Controlling dissolved oxygen content in molten steel |
| US5343491A (en) * | 1991-11-28 | 1994-08-30 | Carbagas And Von Roll Ag | Method of suppressing dust and fumes during electric steel production |
| US5417739A (en) * | 1993-12-30 | 1995-05-23 | Ltv Steel Company, Inc. | Method of making high nitrogen content steel |
| US5830259A (en) * | 1996-06-25 | 1998-11-03 | Ltv Steel Company, Inc. | Preventing skull accumulation on a steelmaking lance |
| US5865876A (en) * | 1995-06-07 | 1999-02-02 | Ltv Steel Company, Inc. | Multipurpose lance |
| US5885323A (en) * | 1997-04-25 | 1999-03-23 | Ltv Steel Company, Inc. | Foamy slag process using multi-circuit lance |
| CN102146499A (zh) * | 2010-02-05 | 2011-08-10 | 鞍钢股份有限公司 | 一种aod喷吹co2生产不锈钢的冶炼方法 |
| US9045805B2 (en) | 2013-03-12 | 2015-06-02 | Ati Properties, Inc. | Alloy refining methods |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES468347A1 (es) * | 1977-03-31 | 1978-12-01 | Union Carbide Corp | Un procedimiento para la obtencion de piezas coladas de me- tal. |
| US4436553A (en) | 1982-01-22 | 1984-03-13 | Union Carbide Corporation | Process to produce low hydrogen steel |
| FR2560891B1 (fr) * | 1984-03-09 | 1989-10-20 | Air Liquide | Procede d'affinage de la fonte |
| US4615730A (en) | 1985-04-30 | 1986-10-07 | Allegheny Ludlum Steel Corporation | Method for refining molten metal bath to control nitrogen |
| DE3912061A1 (de) * | 1989-04-13 | 1990-10-18 | Messer Griesheim Gmbh | Verfahren zur herstellung von legierten stahlmarken |
| US5139569A (en) * | 1989-04-13 | 1992-08-18 | Messer Griesheim | Process for the production of alloy steel grades using treatment gas consisting of CO2 |
| US5190577A (en) * | 1990-12-11 | 1993-03-02 | Liquid Air Corporation | Replacement of argon with carbon dioxide in a reactor containing molten metal for the purpose of refining molten metal |
| DE19540490C1 (de) | 1995-10-23 | 1997-04-10 | Mannesmann Ag | Verfahren zum Entkohlen einer Stahlschmelze |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2855293A (en) * | 1955-03-21 | 1958-10-07 | Air Liquide | Method and apparatus for treating molten metal with oxygen |
| US3046107A (en) * | 1960-11-18 | 1962-07-24 | Union Carbide Corp | Decarburization process for highchromium steel |
| US3252790A (en) * | 1956-06-27 | 1966-05-24 | Union Carbide Corp | Preparation of metals and alloys |
| US3706549A (en) * | 1968-02-24 | 1972-12-19 | Maximilianshuette Eisenwerk | Method for refining pig-iron into steel |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3003865A (en) * | 1959-09-10 | 1961-10-10 | Cameron Iron Works Inc | Decarburizing process for alloy steels containing chromium |
| US3397878A (en) * | 1965-11-19 | 1968-08-20 | Union Carbide Corp | Under-bath tuyere |
| BE755456A (fr) * | 1969-08-29 | 1971-03-01 | Allegheny Ludlum Ind Inc | Decarburation de l'acier fondu |
| US3728101A (en) * | 1970-11-09 | 1973-04-17 | Armco Steel Corp | Process for making stainless steel |
| FR2186974A5 (en) * | 1972-05-31 | 1974-01-11 | Air Liquide | Decarburisation of iron and steel alloys - contg chromium by blowing with oxygen, carbon dioxide and a rare gas |
-
1973
- 1973-06-28 US US374635A patent/US3861888A/en not_active Expired - Lifetime
-
1974
- 1974-05-28 AU AU69443/74A patent/AU6944374A/en not_active Expired
- 1974-06-27 IL IL45137A patent/IL45137A/xx unknown
- 1974-06-27 NO NO742347A patent/NO742347L/no unknown
- 1974-06-27 BR BR5267/74A patent/BR7405267A/pt unknown
- 1974-06-27 FR FR7422449A patent/FR2235198B1/fr not_active Expired
- 1974-06-27 BE BE145977A patent/BE816970A/xx unknown
- 1974-06-27 PL PL1974172235A patent/PL88825B1/pl unknown
- 1974-06-27 FI FI1978/74A patent/FI197874A7/fi unknown
- 1974-06-27 JP JP49072891A patent/JPS5037611A/ja active Pending
- 1974-06-27 SE SE7408502A patent/SE7408502L/ unknown
- 1974-06-27 DD DD179518A patent/DD112468A5/xx unknown
-
1977
- 1977-01-21 US US05/760,841 patent/USRE29584E/en not_active Expired - Lifetime
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2855293A (en) * | 1955-03-21 | 1958-10-07 | Air Liquide | Method and apparatus for treating molten metal with oxygen |
| US3252790A (en) * | 1956-06-27 | 1966-05-24 | Union Carbide Corp | Preparation of metals and alloys |
| US3046107A (en) * | 1960-11-18 | 1962-07-24 | Union Carbide Corp | Decarburization process for highchromium steel |
| US3706549A (en) * | 1968-02-24 | 1972-12-19 | Maximilianshuette Eisenwerk | Method for refining pig-iron into steel |
Cited By (15)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4174212A (en) * | 1978-03-10 | 1979-11-13 | A. Finkl & Sons Co. | Method for the refining of steel |
| US4321088A (en) * | 1978-05-11 | 1982-03-23 | Basf Aktiengesellschaft | Process for treating pig iron melts and steel melts or alloys |
| US4490172A (en) * | 1979-06-29 | 1984-12-25 | Moore William H | Method of melting and refining steel and other ferrous alloys |
| US4409028A (en) * | 1979-10-24 | 1983-10-11 | Moore William H | Process for producing cast iron |
| US4260415A (en) * | 1979-12-12 | 1981-04-07 | Allegheny Ludlum Steel Corporation | Decarburizing molten metal |
| EP0030818A3 (en) * | 1979-12-12 | 1981-12-30 | Allegheny Ludlum Steel Corporation | Improved method of decarburizing molten metal |
| US4746361A (en) * | 1987-04-03 | 1988-05-24 | Inland Steel Company | Controlling dissolved oxygen content in molten steel |
| US5343491A (en) * | 1991-11-28 | 1994-08-30 | Carbagas And Von Roll Ag | Method of suppressing dust and fumes during electric steel production |
| US5417739A (en) * | 1993-12-30 | 1995-05-23 | Ltv Steel Company, Inc. | Method of making high nitrogen content steel |
| US5865876A (en) * | 1995-06-07 | 1999-02-02 | Ltv Steel Company, Inc. | Multipurpose lance |
| US5830259A (en) * | 1996-06-25 | 1998-11-03 | Ltv Steel Company, Inc. | Preventing skull accumulation on a steelmaking lance |
| US5885323A (en) * | 1997-04-25 | 1999-03-23 | Ltv Steel Company, Inc. | Foamy slag process using multi-circuit lance |
| CN102146499A (zh) * | 2010-02-05 | 2011-08-10 | 鞍钢股份有限公司 | 一种aod喷吹co2生产不锈钢的冶炼方法 |
| US9045805B2 (en) | 2013-03-12 | 2015-06-02 | Ati Properties, Inc. | Alloy refining methods |
| US9683273B2 (en) | 2013-03-12 | 2017-06-20 | Ati Properties Llc | Alloy refining methods |
Also Published As
| Publication number | Publication date |
|---|---|
| FR2235198A1 (enrdf_load_stackoverflow) | 1975-01-24 |
| PL88825B1 (enrdf_load_stackoverflow) | 1976-09-30 |
| FR2235198B1 (enrdf_load_stackoverflow) | 1978-01-20 |
| FI197874A7 (enrdf_load_stackoverflow) | 1974-12-29 |
| IL45137A0 (en) | 1974-09-10 |
| BE816970A (fr) | 1974-12-27 |
| NO742347L (enrdf_load_stackoverflow) | 1975-01-27 |
| IL45137A (en) | 1976-09-30 |
| AU6944374A (en) | 1975-12-04 |
| DE2430975A1 (de) | 1975-01-09 |
| BR7405267A (pt) | 1976-02-24 |
| SE7408502L (enrdf_load_stackoverflow) | 1974-12-30 |
| DD112468A5 (enrdf_load_stackoverflow) | 1975-04-12 |
| JPS5037611A (enrdf_load_stackoverflow) | 1975-04-08 |
| USRE29584E (en) | 1978-03-21 |
| DE2430975B2 (de) | 1975-09-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3861888A (en) | Use of CO{HD 2 {B in argon-oxygen refining of molten metal | |
| US3252790A (en) | Preparation of metals and alloys | |
| US3046107A (en) | Decarburization process for highchromium steel | |
| US3754894A (en) | Nitrogen control in argon oxygen refining of molten metal | |
| US4165234A (en) | Process for producing ferrovanadium alloys | |
| US3695946A (en) | Method of manufacturing oriented grain magnetic steel sheets | |
| US5190577A (en) | Replacement of argon with carbon dioxide in a reactor containing molten metal for the purpose of refining molten metal | |
| US4474605A (en) | Process for refining high-chromium steels | |
| US4174212A (en) | Method for the refining of steel | |
| US3930843A (en) | Method for increasing metallic yield in bottom blown processes | |
| KR850000927B1 (ko) | 취련가스에 의한 정련시의 슬로핑방지법 | |
| US3305352A (en) | Process of producing alloys | |
| JPH0776715A (ja) | 炭素含有金属溶融物の脱炭法 | |
| JPS5579821A (en) | Manufacture of low-carbon high-chromium alloy steel by heat-insulated furnace for molten steel | |
| US3929458A (en) | Process for the elaboration of chrome steels | |
| CA1115963A (en) | Method for the refining of steel | |
| RU2103379C1 (ru) | Способ получения низкоуглеродистых сталей | |
| US4141723A (en) | Process for producing stainless steel | |
| US4022613A (en) | Metallurgical material and process for treating iron or steel therewith | |
| US4436553A (en) | Process to produce low hydrogen steel | |
| US3860418A (en) | Method of refining iron melts containing chromium | |
| SU1250582A1 (ru) | Способ выплавки стали в многованной электропечи | |
| SU447433A1 (ru) | Способ выплавки стали | |
| US4066442A (en) | Method of making chrome steel in an electric arc furnace | |
| SU379633A1 (ru) | Способ производства низкоуглеродисто легированной стали |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AS | Assignment |
Owner name: MORGAN GUARANTY TRUST COMPANY OF NEW YORK, AND MOR Free format text: MORTGAGE;ASSIGNORS:UNION CARBIDE CORPORATION, A CORP.,;STP CORPORATION, A CORP. OF DE.,;UNION CARBIDE AGRICULTURAL PRODUCTS CO., INC., A CORP. OF PA.,;AND OTHERS;REEL/FRAME:004547/0001 Effective date: 19860106 |
|
| AS | Assignment |
Owner name: UNION CARBIDE CORPORATION, Free format text: RELEASED BY SECURED PARTY;ASSIGNOR:MORGAN BANK (DELAWARE) AS COLLATERAL AGENT;REEL/FRAME:004665/0131 Effective date: 19860925 |
|
| AS | Assignment |
Owner name: UNION CARBIDE INDUSTRIAL GASES TECHNOLOGY CORPORAT Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:UNION CARBIDE INDUSTRIAL GASES INC.;REEL/FRAME:005271/0177 Effective date: 19891220 |