Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22F—CHANGING THE PHYSICAL STRUCTURE OF NON-FERROUS METALS AND NON-FERROUS ALLOYS
  • C22F1/00—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working
  • C22F1/16—Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working of other metals or alloys based thereon
  • C22F1/18—High-melting or refractory metals or alloys based thereon
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C1/00—Making non-ferrous alloys
  • C22C1/04—Making non-ferrous alloys by powder metallurgy
  • C22C1/045—Alloys based on refractory metals
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S428/00—Stock material or miscellaneous articles
  • Y10S428/922—Static electricity metal bleed-off metallic stock
  • Y10S428/9265—Special properties
  • Y10S428/929—Electrical contact feature
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S428/00—Stock material or miscellaneous articles
  • Y10S428/922—Static electricity metal bleed-off metallic stock
  • Y10S428/9335—Product by special process
  • Y10S428/936—Chemical deposition, e.g. electroless plating

Definitions

• This invention relates to the production and purification of tungsten, and to electric conducting elements made therefrom, especially those which become highly heated in use such as electrical make-and-break contact points, incandescent filaments, etc.
• the customary procedure is first to reduce tungstic oxide by hydrogen with the production or" a granular metallic powder, and next to sin ter the resulting granular substance together into the form of a somewhat porous rod or ingot by the use of a very high tem perature, after which the same is wrought by swaging, drawing, etc., the procedure being substantially the same as was employed in the making of wrought iron in the days when a sufficiently high temperature for the complete fusion of the iron was unattainable.
• Such a metal is silver; and it is within my invention to mix finely divided silver with the previously reduced granular tungsten, and afterwards to compact and sinter the whole, finally raising the temperature to such a degree as wholly to volatilize the silver which takes with it all traces of oxygen.
• the resulting bar or ingot shows no trace Application filed November 5, 1928. Serial No. 317,493.
• Another way of securing the intimate admixture of metals necessary to the performance of this process is to reduce them simultaneously by hydrogen.
• One way in which this can be done is to mix silver chloride intimately with the tungsten or other oxide, prior to the reduction by hydrogen, since silven chloride is likewise reduced under these conditions.
• a still better way is to precipitate the silver compound into the tungstic oxide so as to obtainthe most complete incorporation at all stages of the process.
• This reduction serves merely to change the thorium nitrate to oxide and I find that with the presence of silver as herein described I can work the resulting metal into filament form successfully even with a thoria content up to 3% although the silver is wholly volatilized during the sintering operation. This advantage is present whether or not special additional steps are taken to reduce the thoria to metallic form.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Powder Metallurgy (AREA)

Priority Applications (2)

Applications Claiming Priority (1)

Publications (1)

Family

ID=23233894

Family Applications (1)

Country Status (2)

Cited By (3)

• 1928
  • 1928-11-05 US US317493A patent/US1896606A/en not_active Expired - Lifetime
• 1929
  • 1929-11-04 BE BE365022D patent/BE365022A/xx unknown

Also Published As

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