Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
  • C22C29/02—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on carbides or carbonitrides
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C29/00—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides
  • C22C29/16—Alloys based on carbides, oxides, nitrides, borides, or silicides, e.g. cermets, or other metal compounds, e.g. oxynitrides, sulfides based on nitrides
• • G—PHYSICS
  • G04—HOROLOGY
  • G04B—MECHANICALLY-DRIVEN CLOCKS OR WATCHES; MECHANICAL PARTS OF CLOCKS OR WATCHES IN GENERAL; TIME PIECES USING THE POSITION OF THE SUN, MOON OR STARS
  • G04B37/00—Cases
  • G04B37/22—Materials or processes of manufacturing pocket watch or wrist watch cases
• • 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
  • Y10S428/927—Decorative informative
• • 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
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49579—Watch or clock making
  • Y10T29/49584—Watch or clock making having case, cover, or back
• • 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
  • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
  • Y10T29/00—Metal working
  • Y10T29/49—Method of mechanical manufacture
  • Y10T29/49588—Jewelry or locket making
  • Y10T29/49597—Ornamental stock making

Definitions

• This invention relates to the jewelry art and, more particularly, to the manufacture of articles of jewelry that are similar in appearance to gold jewelry but at the same time are relatively resistant to scratch and crushing.
• the articles of jewelry manufactured in accordance with this invention contain at least 70% by volume and up to 97% by volume of metals selected from the group consisting of tantalum carbide, zirconium nitride, titanium nitride and vanadium nitride.
• the jewelry articles can contain one of the foregoing metals or it can utilize a mixture of two or more of the aforesaid primary metals, as long as the total concentration of primary metal remains within the aforesaid range.
• the primary metal will be present in the articles of jewelry in an amount of from about 85 to 90% by volume.
• the particular primary metal to be employed in any instance will depend to some extent upon the characteristics desired of the final product. Where it is desired that the article of jewelry approach very closely not only the physical appearance but also the specific gravity of gold, then tantalum carbide is the preferred primary metal. Where a somewhat lesser specific gravity is desired, one of the other primary metals can be employed.
• the articles of jewelry should contain, in addition to primary metal, a suitable auxiliary metal.
• the auxiliary metal must be a metal having a melting point lower than the primary metal, preferably at least about 50 C. less.
• the auxiliary metal must also be capable of wetting the primary metal employed at the sintering temperature. Iron, cobalt and nickel and alloys of each of them, meeting the foregoing criteria, are satisfactory auxiliary metals.
• Nickel is the preferred auxiliary metal either by itself in the form of the commercial grade or pure nickel or in the form of alloys of nickel and chromium. Suitable nickelchromium alloys will contain from about five to fifty percent by volume of chromium. In such nickel-chromium alloys, copper can also be present in an amount from 1 to 30% by volume. When copper is present in the nickelchror nium alloy, the total volume of chromium and nickel combined should not be greater than the volume of nickel.
• a preferred auxiliary metal is an alloy containing 80 parts by volume of nickel and 20 parts by volume of chromium. Nickel-molybdenum alloys are also suitable.
• auxiliary metal is preferably present in an amount of up to 20% by volume in the finished product. For some applications, particularly when used along with titanium nitride, up to 30% by volume of auxiliary metals can be added. Most preferably, the auxiliary metal should be present in an amount of at least 10%.
• the combinations of auxiliary and primary metals can be varied so as to achieve particularly desirable properties. For example, a material can be achieved which will be completely non-magnetic. Such a material would be useful for watch cases or the like. Using other combinations of primary and auxiliary metals, the material achieved will be only weakly ferromagnetic, having a saturation value of 41m lower than 20 gauss. In all instances, the product retains the characteristic color and outward physical appearance of gold.
• the gold colored articles made by means of this invention are particularly useful when formed into items of jewelry such as, for example, watch cases, watch bracelets and bands, rings, bracelets, charms and pins of all types.
• Utility is not, of course, limited to jewelry but can be used for other ornamental or utilitarian purposes where the cold coloration is necessary or desirable along with the strength and scratch resistance produced by this invention.
• the articles of this invention are prepared by conventional powder metallurgical techniques from powdered starting materials.
• the primary metal or metals along with any auxiliary metals are obtained and mixed in powdered form, pressed into the desired form, and thereafter sintered.
• Conventional lubricants can also be added to the mixture to facilitate pressing.
• the particle size of the powder is as in conventional powder metallurgical processes. Sinten'ng will take place at the desired sintering temperature for the composition used, the temperature being within the range of 1200 to 2200 C. and for a time to achieve complete sintering. Sintering preferably takes placein a protective atmosphere, i.e., an atmosphere that is non-reactive with the metallic components present. Thus, for example, sintering can take place after evacuation of air or it can take place in an atmosphere of an inert gas such as argon.
• a protective atmosphere i.e., an atmosphere that is non-reactive with the metallic components present.
• sintering can take place after evacuation of air or it can take place in an atmosphere of an inert gas such as argon.
• the powder mixture can be hot pressed into the desired shape in a mold or other pressure device heated to the sintering temperature with a pressure of from about 50 to 350 kg. per cm. and a time of at least about 2 to 10 minutes.
• the powder mixture can be compressed to bring the particles together into the proper shape, pre-sintered only very briefly and then finally sintered at some later date. Because of the hardness of the product, machining may require the use of diamond tools.
• the final article is then finished by grinding and polishing to bring out the lustre and smoothness desired.
• a mixture is prepared of parts by volume of commercial grade tantalum carbide powder (which contains about 1% niobium carbide) and 15 parts of commercial nickel carbonyl powder.
• a suflicient amount of acetone is added to facilitate blending and the mixture is ground in a conventional ball mill having cemented carbide balls.
• the powder is wetted with a solution of camphor in ether.
• the ether evaporates, with the camphor remaining as a lubricant, the powder is poured into a mold and compressed at a pressure of 1500 kg. per cm. The pressed compacts are then pre-sintered for 15 minutes at 800 C.
• An article of jewelry having. the color and physical appearance of gold and capable of being polished which consists essentially of a sintered mixture of between 70 and 90-parts lnyvolumeof at leastone compound of the groupconsisting of tantalum carbide, zirconium nitride,
• An article according to claim 1 containing titanium.
• nitride and a metal of the group consisting of nickel and nickel base alloys.
• An article according to claim 1 containing vanadium nitride andametal of the group consisting of nickel and nickel base alloys.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Manufacturing & Machinery (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Adornments (AREA)
• Powder Metallurgy (AREA)

Applications Claiming Priority (1)

Publications (1)

Family

ID=3625131

Family Applications (1)

Country Status (6)

Cited By (9)

Families Citing this family (12)

• 1967
  • 1967-12-01 AT AT1085467A patent/AT284477B/de active
• 1968
  • 1968-03-12 CH CH368568D patent/CH368568A4/de not_active IP Right Cessation
  • 1968-10-25 JP JP43077383A patent/JPS5140083B1/ja active Pending
  • 1968-11-13 DE DE19681808600 patent/DE1808600A1/de active Pending
  • 1968-11-14 FR FR1591774D patent/FR1591774A/fr not_active Expired
  • 1968-11-27 US US779635A patent/US3684463A/en not_active Expired - Lifetime

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