Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C32/00—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ
  • C22C32/001—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides
  • C22C32/0015—Non-ferrous alloys containing at least 5% by weight but less than 50% by weight of oxides, carbides, borides, nitrides, silicides or other metal compounds, e.g. oxynitrides, sulfides, whether added as such or formed in situ with only oxides with only single oxides as main non-metallic constituents
  • C22C32/0031—Matrix based on refractory metals, W, Mo, Nb, Hf, Ta, Zr, Ti, V or alloys thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
  • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
  • B21C25/00—Profiling tools for metal extruding
  • B21C25/02—Dies
  • B21C25/025—Selection of materials therefor

Definitions

• d1es bemg made of a predominant amount of molyb- 2,949,358 8/1960 Alexander et a1.
• Extrusion dies for the processing of various metals including non-ferrous metals and alloy steels are wellknown. Conventional dies of this type are made from stellites and high temperature steels. Some dies are also made from such oxide materials as zirconia. However, these materials have been found to be disadvantageous. They are difficult to work and because of their brittleness they develop cracks during operation. Consequently, their useful life is quite short.
• the dies of this invention contain from 85 to 98 percent by volume of molybdenum or tungsten with the remainder being a zirconia phase.
• the molybdenum or tungsten phase will be in excess from 85 to 95 percent by volume of the composition.
• the zirconia phase is preferably stabilized by a zirconia stabilizing oxide.
• zirconia stabilizing oxides include calcium oxide, magnesium oxide and oxides of cerium and yttrium. Where employed, the stabilizing oxides are present in an amount of up to about 30 percent by volume of the zirconia phase.
• the dies of this invention are prepared by conventional powder metallurgical techniques.
• the powdered materials employed preferably have a particle size of from 0.1 to 30 microns.
• the powdered materials are mixed together and then compressed to form compacts having approximately the desired final shape.
• the pressures employed can range from 15,000 to 80,000 p.s.i.
• the pressed compacts are then sintered in a reducing or inert atmosphere as, for example, in a hydrogen atmosphere or in an atmosphere of an inert gas such as helium or argon, or the like.
• the sintering temperature should be from about l,700 to 2,200 C. If desired, pressure can be maintained during sintering, although it is not required.
• Sintering time will depend upon the size and thickness of the compact but will generally range from about 2 to about 30 hours.
• the desired final form of the die is obtained by machining to the final shape. More complex shapes can be made by spark erosion.
• the final die produced in accordance with this invention has along service life and can be successfully used for the extrusion of steel or non-ferrous metals. Furthermore, the nature of the die of this invention generally eliminates the tendcncy of welding of the die to the extruded material. Consequently, it is generally possible, when using the dies of this invention, to dispense with the use oflubricants during extrusion without risking the likelihood of particles of extruded metal sticking to the die.
• a suitable extrusion die can be manufactured by mixing 94.5 weight per cent of fine molybdenum powder having a particle size of 4 microns, 5.1 percent by weight of powdered zirconia having a particle size of l and 0.4 weight per cent of magnesium oxide (magnesia) having a particle size of 0.1. Thereafter, the mixture is pressed to form a compact by application of pressure using conventional powder metallurgical techniques of 40,000 p.s.i. The pressed compacts are then sintered at 2,000 C. for 8 hours in a hydrogen atmosphere. They are thereafter permitted to cool in hydrogen and finally the final desired form of the die is obtained by machining the sintered compacts.
• An extrusion die for the processing of metallic materials said extrusion die consisting essentially in excess of percent by volume but not more than percent by volume of molybdenum or tungsten, the remainder being a zirconia phase.
• An extrusion die as in claim 1 consisting essentially of molybdenum and zirconia.
• An extrusion die as in claim consisting essentially of tungsten and zirconia.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Chemical & Material Sciences (AREA)
• Materials Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Powder Metallurgy (AREA)
• Compositions Of Oxide Ceramics (AREA)

Applications Claiming Priority (1)

Publications (1)

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Family Applications (1)

Country Status (9)

Cited By (5)

Families Citing this family (2)

Citations (5)

• 1970
  • 1970-02-02 AT AT90670A patent/AT294529B/de not_active IP Right Cessation
  • 1970-12-31 DE DE2064674A patent/DE2064674C3/de not_active Expired
• 1971
  • 1971-01-11 NL NLAANVRAGE7100332,A patent/NL172343C/xx not_active IP Right Cessation
  • 1971-01-18 GB GB1295413D patent/GB1295413A/en not_active Expired
  • 1971-01-22 FR FR7102078A patent/FR2080429A5/fr not_active Expired
  • 1971-01-25 BE BE761997A patent/BE761997A/nl not_active IP Right Cessation
  • 1971-01-29 US US00111136A patent/US3791799A/en not_active Expired - Lifetime
  • 1971-02-02 CH CH148671A patent/CH552067A/xx not_active IP Right Cessation
  • 1971-02-02 JP JP713626A patent/JPS5440487B1/ja active Pending

Patent Citations (5)

Non-Patent Citations (2)

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