Patents Assigned to Williams Gold Refining Company
  • Patent number: 4802436
    Abstract: A continuous casting furnace (10) of modular design. The furnace is made of a crucible section (16) a feed section (18) and a die section (12). Each of these various sections are separable from the other parts, and each of these parts is in turn made up of various individual components. Thus, the crucible section includes a refractory liner (24) made of a non carbon containing material which may be disposed within a monolithic graphite crucible (22). The graphite crucible is provided with a cylindrical aperture at its bottom which receives a feed tube (30), there being a soft seal (32) between the bottom of the liner (24) and the top of the feed tube (30). The feed section and the die section are generally formed in the same manner in that there is a non carbon containing refractory tubular member (48, 64) disposed within a graphite member (50, 62). Between the feed section (18) and the die section (12) is a soft seal (66).
    Type: Grant
    Filed: July 21, 1987
    Date of Patent: February 7, 1989
    Assignees: Williams Gold Refining Company, Rautomead Limited
    Inventors: Robert Wilson, Jerry C. LaPlante
  • Patent number: 4399096
    Abstract: A brazing alloy composition for joining chromium containing base metal alloys containing, by weight, palladium about 39%-60%, nickel about 20%-47.5%, and at least one element selected from the group consisting of silver 0-35%, tin 0-32%, indium 0-32% and gallium 0-11%; and optionally containing one or more elements selected from the group consisting of gold 0-10%, germanium 0-4.4%, silicon 0-2.9% and about 0.025% of a known deoxidizer such as lithium. The alloy exhibits good wetting and flowing characteristics and has excellent strength and corrosion resistance at elevated temperatures. The brazing alloy is particularly useful for joining chromium containing baese metal alloys of the type which are used in the porcelain-fused-to-metal technic in dental prosthetics.
    Type: Grant
    Filed: June 7, 1982
    Date of Patent: August 16, 1983
    Assignee: Williams Gold Refining Company Incorporated
    Inventors: Dwarika P. Agarwal, Clyde E. Ingersoll
  • Patent number: 4249943
    Abstract: An alloy composition for dental use containing, by weight, aluminum 0-3.0%, cobalt 0-20.0%, chromium 10.0-20.0%, manganese 0-1.5%, molybdenum 6.0-18.0%, nickel 58.5-77.0% and silicon 0-2.0%. The alloy retains the corrosion resistance properties found in nickel-chromium base alloys while having reduced yield strength typical of gold alloys thereby resulting in greater ease of grinding, polishing and manipulation. The alloy finds use as a porcelain substrate alloy and also as a crown and bridge or partial denture alloy.
    Type: Grant
    Filed: October 11, 1978
    Date of Patent: February 10, 1981
    Assignee: Williams Gold Refining Company Incorporated
    Inventors: M. Hamdi A. Mohammed, Dwarika P. Agarwal, Clyde E. Ingersoll
  • Patent number: 4201577
    Abstract: An alloy composition enabling the amount of silver therein to be limited significantly or preferably eliminated altogether while maintaining the castability, strength properties and physical properties including melting range and coefficient of thermal expansion compatible with available porcelain products. The alloy composition contains, by weight, silver 0-11.0%, aluminum 0-1%, gold 31.8-63.16%, boron 0-0.13%, calcium 0-0.12%, copper 0-5.0%, iron 0-0.75%, gallium 0-5.0%, indium 0.5-10.55%, lithium 0-0.04%, nickel 0-2%, palladium 28.96-57.97%, rhenium 0-0.25%, ruthenium 0-1.8%, silicon 0-0.0125%, tin 0-7.5%, titanium 0-0.06%, vanadium 0-0.12% and zinc 0-1.98%.
    Type: Grant
    Filed: November 8, 1978
    Date of Patent: May 6, 1980
    Assignee: Williams Gold Refining Company Incorporated
    Inventors: Clyde E. Ingersoll, Dwarika P. Agarwall
  • Patent number: 4089676
    Abstract: A method for producing nickel powder of controlled geometry useful for conductive or resistive pastes or inks. A nickel salt is precipitated by means of hydrazine, an alkali metal base is added to the precipitate, and the resulting mixture is heated under ambient pressure until nickel powder is precipitated. The geometry such as powder surface area, particle size, and particle shape of the nickel powder end product is controlled by means of the added amount of alkali metal base or added amount of hydrazine and in some instances by means of the temperature.
    Type: Grant
    Filed: May 24, 1976
    Date of Patent: May 16, 1978
    Assignee: Williams Gold Refining Company Incorporated
    Inventor: James D. Grundy