US3194648A - Methods of obtaining metal powder from ores or oxides - Google Patents
Methods of obtaining metal powder from ores or oxides Download PDFInfo
- Publication number
- US3194648A US3194648A US293816A US29381663A US3194648A US 3194648 A US3194648 A US 3194648A US 293816 A US293816 A US 293816A US 29381663 A US29381663 A US 29381663A US 3194648 A US3194648 A US 3194648A
- Authority
- US
- United States
- Prior art keywords
- powder
- ferrochromium
- mixture
- iron ore
- metal powder
- 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
- 239000000843 powder Substances 0.000 title claims description 19
- 229910052751 metal Inorganic materials 0.000 title claims description 16
- 239000002184 metal Substances 0.000 title claims description 16
- 238000000034 method Methods 0.000 title claims description 13
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 24
- 229910000604 Ferrochrome Inorganic materials 0.000 claims description 12
- 229910052742 iron Inorganic materials 0.000 claims description 12
- 239000000203 mixture Substances 0.000 claims description 11
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 9
- 238000010438 heat treatment Methods 0.000 claims description 5
- 150000003839 salts Chemical class 0.000 claims description 5
- 238000002156 mixing Methods 0.000 claims description 4
- 239000003513 alkali Substances 0.000 claims description 3
- 239000007864 aqueous solution Substances 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 238000000227 grinding Methods 0.000 claims description 2
- NROKBHXJSPEDAR-UHFFFAOYSA-M potassium fluoride Chemical compound [F-].[K+] NROKBHXJSPEDAR-UHFFFAOYSA-M 0.000 description 10
- 238000006722 reduction reaction Methods 0.000 description 9
- 239000003054 catalyst Substances 0.000 description 6
- 238000006243 chemical reaction Methods 0.000 description 6
- 229910052799 carbon Inorganic materials 0.000 description 5
- 238000003801 milling Methods 0.000 description 5
- 239000011698 potassium fluoride Substances 0.000 description 5
- 235000003270 potassium fluoride Nutrition 0.000 description 5
- 239000002893 slag Substances 0.000 description 4
- 239000007787 solid Substances 0.000 description 4
- QDOXWKRWXJOMAK-UHFFFAOYSA-N chromium(III) oxide Inorganic materials O=[Cr]O[Cr]=O QDOXWKRWXJOMAK-UHFFFAOYSA-N 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 2
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 2
- 230000004913 activation Effects 0.000 description 2
- 239000003638 chemical reducing agent Substances 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000011651 chromium Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 229910052700 potassium Inorganic materials 0.000 description 2
- 239000011591 potassium Substances 0.000 description 2
- BWHMMNNQKKPAPP-UHFFFAOYSA-L potassium carbonate Substances [K+].[K+].[O-]C([O-])=O BWHMMNNQKKPAPP-UHFFFAOYSA-L 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 229910000616 Ferromanganese Inorganic materials 0.000 description 1
- 229910000628 Ferrovanadium Inorganic materials 0.000 description 1
- 235000014676 Phragmites communis Nutrition 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 230000002596 correlated effect Effects 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 239000011363 dried mixture Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- -1 ferrochromium Chemical class 0.000 description 1
- 239000004615 ingredient Substances 0.000 description 1
- DALUDRGQOYMVLD-UHFFFAOYSA-N iron manganese Chemical compound [Mn].[Fe] DALUDRGQOYMVLD-UHFFFAOYSA-N 0.000 description 1
- PNXOJQQRXBVKEX-UHFFFAOYSA-N iron vanadium Chemical compound [V].[Fe] PNXOJQQRXBVKEX-UHFFFAOYSA-N 0.000 description 1
- 239000006148 magnetic separator Substances 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
- 238000005272 metallurgy Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 238000002161 passivation Methods 0.000 description 1
- 229910000027 potassium carbonate Inorganic materials 0.000 description 1
- 239000011541 reaction mixture Substances 0.000 description 1
- 230000009257 reactivity Effects 0.000 description 1
- 239000011369 resultant mixture Substances 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B1/00—Preliminary treatment of ores or scrap
- C22B1/14—Agglomerating; Briquetting; Binding; Granulating
- C22B1/24—Binding; Briquetting ; Granulating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
- B22F9/00—Making metallic powder or suspensions thereof
- B22F9/16—Making metallic powder or suspensions thereof using chemical processes
- B22F9/18—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds
- B22F9/20—Making metallic powder or suspensions thereof using chemical processes with reduction of metal compounds starting from solid metal compounds
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/0046—Making spongy iron or liquid steel, by direct processes making metallised agglomerates or iron oxide
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/006—Starting from ores containing non ferrous metallic oxides
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B13/00—Making spongy iron or liquid steel, by direct processes
- C21B13/008—Use of special additives or fluxing agents
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B15/00—Other processes for the manufacture of iron from iron compounds
-
- 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
Definitions
- One of the principal objects of the invention is to provide a process for obtaining metal powders from ores or oxides by a series of steps followed by a reduction with a reducing substance.
- the invention accordingly comprises the several steps ⁇ and the relation of one or more of such steps with respect to each of the others, all as exemplified in the following detailed disclosure, and the scope ⁇ of the application of which will be indicated in the claims.
- the reduction :of the aforesaid oxides in their solid state can be carried out only in a vacuum. Such a process can be economical only, however, if it avoids too high temperatures as Well as too long times.
- the instantY invention renders it possible to reduce not only the reaction temperatureconsiderably, but also to reduce markedly the reaction time. Broadly speaking, this is obtained by an accurately determined mechanical treatment and the addition of pre-determined small amounts of one or more catalysts.
- the other step for reducing the reaction time is the addition of catalysts in the form of metal salts of alkalies and of alkaline earths; potassium fluoride and potassium carbonate have been found to be particularly suitable catalysts.
- the maximum effect is obtained with a definite yamount which lies between about 0.1 percent and 0.6 percent, and need-s to be determined separately for every material.
- ferrochromium powder For the production of ferrochromium powder from a chromic iron ore, the following exemplified method may be used: A certain amount of carbon powder is added to the ore, the amount of the powder being that which is necessary for the reduction of the chromium and the iron. The ore and the powder are then milled in a ball mill for a predetermined time. The powder will be mashed into a stiff paste, with the aid of a solution which contains the necessary amount of potassium uoride, then dried and briquetted. After the heating, for reduction, in a vacuum, the briquettes will be comminuted, such as crushed, and the ferrochromium powder be separated from the slag powder in accordance with well-known suitable processes.
- Example A chromic iron ore containing 15.5% iron ⁇ oxide and 60.87% chromium oxide was ground to a ne powder; 17% carbon powder was admixed, and the milling continued for one-half of one hour (0.5 hn).
- One kilogram (2.2 lbs.) of the foregoing mixture was mixed with cu. cm. (6.1 cu. in.) of an aqueous solution of potassium fluoride (1 normal). The mixture of the ore and the carbon after the drying conta-ined 0.59% potassium fluoride. Following the briquetting, the mixture was heated in a vacuum of about 0.1 mm. Hg and a temperature of 1300 C. (2372 F.) for 10 hours.
- the heating to the reaction temperature must be correlated to the occurring gas generation.
- the metallic ferrochromium powder must be separated from the slag powder. This separation was carried out, following a comminution of the heated product, simply with the -aid of a magnetic separator.
- the metal thus obtained had about 61% chromium and 0.4% carbon.
- the ferrochromium metal was powdered, then mixed with 2% chromic oxide (Cr203) and 0.1% of potassium uoride admixed, and thereafter again heated at a temperature of from 1200 C. (2192 F.) and 1300 C. (2372 F.).
- the resultant products are strongly sintered, practically carbon-free briquettes immediately usable for the alloying in steel production.
- a method of obtaining ferrochromium metal powder from chromic iron ore comprising comminuting said chromic iron ore to a line powder;
- a catalyst selected form the group consisting of metal salts of alkalies and of salts of alkaline earths, said salts being added in the form of an aqueous solution;
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Mechanical Engineering (AREA)
- Manufacture And Refinement Of Metals (AREA)
Description
July13,1965 NAESER ETAL 3,194,648
state.
United States Patent O 3,194,643 METHODS F OBTANING METAL POWDER FRM GRES 0R OXIDES Gerhard Naeser, Duisburg, and Norbert Dautzenberg, Wattenscheid, Germany, assignors to Mannesmann Aktiengesellschaft, Dusseldorf, Germany, a corporation of Germany Filed July 9, 1963, Ser. No. 293,816 Claims priority, application Germany, July 30, 1962, M 53 734 The invention relates to metallurgy, and relates more particularly tomethods of obtaining metal powder-s from ores or oxides by their chemical reduction.
One of the principal objects of the invention is to provide a process for obtaining metal powders from ores or oxides by a series of steps followed by a reduction with a reducing substance.
It is a further object of the invention to include among the aforesaid steps an activation by means of mechanical treatment and the addition of a catalyst.
The invention accordingly comprises the several steps `and the relation of one or more of such steps with respect to each of the others, all as exemplified in the following detailed disclosure, and the scope `of the application of which will be indicated in the claims.
For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description, taken in connection with the accompanying dr-awings, in which the single view is a graph showing the rate of reduction of an oxide in percent for two different heating periods, plotted over milling time in minutes.
Most metals are today obtained by melting. For some special purposes, however, such as for instance the obtaining of spongy iron, there have been developed methods in which both ingredients, namely the metal oxide and the reduction carbon are brought to react in the solid The foregoing method has, however, to date not been used for economically and technically particularly important metals, such as ferrochromium, ferromanganese, or ferrovanadium.
The reduction :of the aforesaid oxides in their solid state can be carried out only in a vacuum. Such a process can be economical only, however, if it avoids too high temperatures as Well as too long times.
The instantY invention renders it possible to reduce not only the reaction temperatureconsiderably, but also to reduce markedly the reaction time. Broadly speaking, this is obtained by an accurately determined mechanical treatment and the addition of pre-determined small amounts of one or more catalysts.
Concentrated research of various reactions has yielded the insight that the reduction `of metal `oxides with solid or gaseous lreduction media can be advanced by a mechanical treatment of the solid particles prior to the reaction, for instance by rolling, hammering, or milling. As shown in the drawing, -this treatment leads alternatingly to an activation and passivation of the chemical reaction. In accordance with the invention, the reaction should be carried out at that milling time which corresponds to a maximum of reactivity. This optimum milling time depends on the con-struction and size of the mill, and needs to be determined with the aid of the graphs shown in the drawing.
The other step for reducing the reaction time is the addition of catalysts in the form of metal salts of alkalies and of alkaline earths; potassium fluoride and potassium carbonate have been found to be particularly suitable catalysts. The maximum effect is obtained with a definite yamount which lies between about 0.1 percent and 0.6 percent, and need-s to be determined separately for every material.
For the production of ferrochromium powder from a chromic iron ore, the following exemplified method may be used: A certain amount of carbon powder is added to the ore, the amount of the powder being that which is necessary for the reduction of the chromium and the iron. The ore and the powder are then milled in a ball mill for a predetermined time. The powder will be mashed into a stiff paste, with the aid of a solution which contains the necessary amount of potassium uoride, then dried and briquetted. After the heating, for reduction, in a vacuum, the briquettes will be comminuted, such as crushed, and the ferrochromium powder be separated from the slag powder in accordance with well-known suitable processes.
Example A chromic iron ore containing 15.5% iron `oxide and 60.87% chromium oxide was ground to a ne powder; 17% carbon powder was admixed, and the milling continued for one-half of one hour (0.5 hn). One kilogram (2.2 lbs.) of the foregoing mixture was mixed with cu. cm. (6.1 cu. in.) of an aqueous solution of potassium fluoride (1 normal). The mixture of the ore and the carbon after the drying conta-ined 0.59% potassium fluoride. Following the briquetting, the mixture was heated in a vacuum of about 0.1 mm. Hg and a temperature of 1300 C. (2372 F.) for 10 hours. In order to avoid too much gas yield and the resultant detrimental loosening of the reaction mixture, the heating to the reaction temperature must be correlated to the occurring gas generation. After the resultant mixture has been cooled, the metallic ferrochromium powder must be separated from the slag powder. This separation was carried out, following a comminution of the heated product, simply with the -aid of a magnetic separator. The metal thus obtained had about 61% chromium and 0.4% carbon. For the complete elimination of the carbon, the ferrochromium metal was powdered, then mixed with 2% chromic oxide (Cr203) and 0.1% of potassium uoride admixed, and thereafter again heated at a temperature of from 1200 C. (2192 F.) and 1300 C. (2372 F.). The resultant products are strongly sintered, practically carbon-free briquettes immediately usable for the alloying in steel production.
Since certain changes in carrying out the above process could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.
Having thus described the invention, what we claim as new and desire to be secured by Letters Patent, is as follows:
1. A method of obtaining ferrochromium metal powder from chromic iron ore comprising comminuting said chromic iron ore to a line powder;
mixing said finely powdered chromic iron ore with carbon powder and subjecting the resulting mixture to continued grinding;
blending into the resulting mixture 0.1 to 0.6%, based on the weight of said mixture, of a catalyst selected form the group consisting of metal salts of alkalies and of salts of alkaline earths, said salts being added in the form of an aqueous solution;
drying and briquetting said mixture;
heating the resulting briquettes under vacuum to about 1300o C. to bring about reduction of the chromic i-ron ore to ferrochromium;
cooling and comminuting the reduced ore;
and subsequently separating the ferrochromium metal powder from the slag.
2. A method according to claim 1 in which said catalyst is potassium fluoride which is being present in the dried mixture in an amount of about 0.59% by Weight.
3. A. method as claimed in claim 1, in which the ferroehromium powder separated from the slag is mixed with about 2% by weight of Cr2O3 and about 0.1% by weight of potassium fluoride and then heated to a temperature in the range between 1200 and 1300 C., in order to eliminate the carbon present in said ferrochromium powder.
Reerenees Cited by the Examiner UNITED STATES PATENTS 2,108,043 2/ 38 Crist 75-33 2,290,734 7/42 Brassert 75-208 2,380,405 7/45 Buehl 75-33 3,068,090 12/62 Reed et al 75-33 3,097,945 7/63 Paris et al. 75-5 FGREIGN PATENTS 645,030 10/50 Great Britain.
CARL D. QUARFORTH, Primary Examiner. REUBEN EPSTEIN, Examiner.
Claims (1)
1. A METHOD OF OBTAINING FERROCHROMIUM METAL POWDER FROM CHROMIC IRON ORE COMPRISING COMMINUTING SAID CHROMIC IRON ORE TO A FINE POWDER; MIXING SAID FINELY POWDERED CHROMIC IRON ORE WITH CARBON POWDER AND SUBJECTING THE RESULTING MIXTURE TO CONTINUED GRINDING; BLENDING INTO THE RESULTING MIXTURE 0.1 TO 0.6%, BASED ON THE WEIGHT OF SAID MIXTURE, OF A CATLYST SELECTED FORM THE GROP CONSISTING OF METAL SALTS OF ALKALIES AND OF SALTS OF ALKALINE EARTHS, SAID SALTS ADDED IN THE FORM OF AN AQUEOUS SOLUTION; DRYING AND BRIQUETTING SAID MIXTURE; HEATING THE RESULTING BRIQUETTES UNDER VACUUM TO ABOUT 1300*C. TO BRING ABOUT REDUCTION OF THE CHROMIC IRON ORE TO FERROCHROMIUM; COOLING AND COMMINUTING THE REDUCED ORE; AND SUBSEQUENTLY SEPARATING THE FERROCHROMIUM METAL POWDER FROM THE SLAG.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEM0053734 | 1962-07-30 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3194648A true US3194648A (en) | 1965-07-13 |
Family
ID=7307794
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US293816A Expired - Lifetime US3194648A (en) | 1962-07-30 | 1963-07-09 | Methods of obtaining metal powder from ores or oxides |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US3194648A (en) |
| DE (1) | DE1433337A1 (en) |
| GB (1) | GB1045167A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2108043A (en) * | 1934-09-21 | 1938-02-15 | Titanium Steel Alloy Company | Process for making steel and iron alloys |
| US2290734A (en) * | 1940-02-14 | 1942-07-21 | Minerals And Metals Corp | Manufacture of metal products |
| US2380406A (en) * | 1943-10-27 | 1945-07-31 | Russell C Buchi | Production of low sulphur sponge iron |
| GB645030A (en) * | 1947-02-08 | 1950-10-25 | Davide Primavesi | Improvements in or relating to the reduction and sintering of moulded bodies containing reducible metal compounds |
| US3068090A (en) * | 1960-12-27 | 1962-12-11 | R N Corp | Alkali metal salts and base additions in non-titaniferous ore reductions |
| US3097945A (en) * | 1959-02-07 | 1963-07-16 | Cie De Pont A Mousson | Process of agglomerating fines of materials containing iron of which a portion has been completely reduced |
-
1962
- 1962-07-30 DE DE19621433337 patent/DE1433337A1/en active Pending
-
1963
- 1963-06-12 GB GB23441/63A patent/GB1045167A/en not_active Expired
- 1963-07-09 US US293816A patent/US3194648A/en not_active Expired - Lifetime
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2108043A (en) * | 1934-09-21 | 1938-02-15 | Titanium Steel Alloy Company | Process for making steel and iron alloys |
| US2290734A (en) * | 1940-02-14 | 1942-07-21 | Minerals And Metals Corp | Manufacture of metal products |
| US2380406A (en) * | 1943-10-27 | 1945-07-31 | Russell C Buchi | Production of low sulphur sponge iron |
| GB645030A (en) * | 1947-02-08 | 1950-10-25 | Davide Primavesi | Improvements in or relating to the reduction and sintering of moulded bodies containing reducible metal compounds |
| US3097945A (en) * | 1959-02-07 | 1963-07-16 | Cie De Pont A Mousson | Process of agglomerating fines of materials containing iron of which a portion has been completely reduced |
| US3068090A (en) * | 1960-12-27 | 1962-12-11 | R N Corp | Alkali metal salts and base additions in non-titaniferous ore reductions |
Also Published As
| Publication number | Publication date |
|---|---|
| GB1045167A (en) | 1966-10-12 |
| DE1433337A1 (en) | 1969-02-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1288572C (en) | Macrocrystalline tungsten monocarbide powder and process for producing | |
| EP1041578A2 (en) | Process for converting uranium metal alloys to UO2 powder and pellets | |
| US3887680A (en) | Process for recovering tungsten from tungsten carbides containing an iron group of metals | |
| US4806155A (en) | Method for producing dysprosium-iron-boron alloy powder | |
| US4039325A (en) | Vacuum smelting process for producing ferromolybdenum | |
| US2733126A (en) | Ukanium liberation | |
| US3194648A (en) | Methods of obtaining metal powder from ores or oxides | |
| US4113479A (en) | Vacuum smelting process for producing ferrotungsten | |
| US3275564A (en) | Process of fabrication of sintered compounds based on uranium and plutonium | |
| US2990267A (en) | Preparation of metal powders | |
| US2833645A (en) | Reduction of chromium oxides | |
| US3549350A (en) | Method of treating scrap metal | |
| US3737301A (en) | Process for producing iron-molybdenum alloy powder metal | |
| US2839379A (en) | Metal aggregate | |
| CA1115066A (en) | Process for the production of extra fine cobalt powder | |
| GB1137932A (en) | Process for the production of nickel-refractory oxide powders | |
| JPS5514825A (en) | Production of iron powder for welding, cutting and powder metallurgy from converter dust | |
| US3066022A (en) | Process for the manufacture of pulverized iron | |
| US3635699A (en) | Method of producing sized particles of low-carbon ferrochromium | |
| US4294609A (en) | Process for the reduction of iron oxide | |
| GB813999A (en) | Production of titanium alloys in powder form | |
| US4767454A (en) | Process for the preparation of finely particulate chromium metal powder having a low oxygen content | |
| US3791815A (en) | Process for lanthanide and actinide metals ore reduction | |
| US2829041A (en) | Method for reducing the carbon content of carbon-containing ferrochromium | |
| JPS62207805A (en) | Method for producing titanium-containing alloy powder |