Patents Assigned to Leach & Garner Co.
  • Patent number: 5180551
    Abstract: A unique hardenable gold based alloy, especially a 14 karat gold alloy containing gold, silver, copper, zinc, cobalt and an alternative alloy additionally containing iridium. The alloy has a fine grained structure, a lower hardness in the soft condition, a nice yellow color and a capability to be hardened to an exceptional hardness value. The alloy contains approximately 58.3% gold (Au), between about 10% to about 14% silver (Ag), between about 2.5% to about 3.0% zinc (Zn), between about 0.2% to about 1.0% cobalt (Co) and the balance of the alloy being copper (Cu) with the special provision that the ratio of the weight percent amounts of copper to, the sum of the silver and two (2) times the zinc amount, [Cu/(Ag+2Zn)], has a value of between about 1.3 to about 2.5. The copper to silver weight percent ratio [Cu/Ag] of between about 2.0 to about 3.8, in combination with the ratio of copper to, silver+2.times.
    Type: Grant
    Filed: October 30, 1991
    Date of Patent: January 19, 1993
    Assignee: Leach & Garner Co.
    Inventor: Dwarika P. Agarwal
  • Patent number: 5130689
    Abstract: Gold, copper, silver, palladium or aluminum and their alloys, but preferably gold or gold alloy, which may be in the form a wire, has deposited thereon or contained within the wire, a material such as metals or metal alloys which diffuse into the gold or into the other listed metals. With the passage of time and exposure to temperature the deposited metal or metal alloy continues to diffuse into the gold forming intermetallics with the gold and thereby causing the resistivity of the gold to increase and causing the gold to become progressively more brittle until such time as the gold wire ruptures at a stress point. At a given temperature the elapsed time until rupture takes place depends upon the metal or metal alloys deposited on or contained within the gold. Lead, indium, gallium, tin, bismuth and aluminum and the alloys of these metals diffuse into and form intermetallics with the gold.
    Type: Grant
    Filed: January 16, 1991
    Date of Patent: July 14, 1992
    Assignee: Leach & Garner Co.
    Inventors: Grigory Raykhtsaum, Dwarika P. Agarwal