Dental alloys for porcelain-fused-to-metal restorations
Abstract
Abstract Palladium based dental alloys are provided consisting essentially of, on a weight percent basis: Gold: 8-25 Gallium: 0-10 Boron: 0.05-0.25 Rhenium: 0.1-0.5 Indium and/or Tin: 0-20 Zinc: 0-4 and the balance, palladium--with the proviso that when a mixture of gallium, indium and/or tin are incorporated in the alloy, if gallium is present in amounts less than or equal to about 4% by weight, then the total weight percent of gallium, indium and/or tin ranges from about 12 to 20; whereas, if gallium is present in amounts from greater than about 4% to 10% by weight, then the total weight percent of gallium, indium and/or tin ranges from about 8 to 20; and when a mixture of zinc, indium and/or tin are incorporated in the alloy, zinc is present in an amount less than 4% and is present in the alloy in lieu of gallium, said alloy exhibiting a yield strength greater than 50,000 psi, an ultimate tensile strength of greater than 60,000 psi, an elongation greater than 10%, and a melting point ranging from 2200°-2400° F. Essentially bubble-free, porcelain-fused-to-metal dental restorations are also provided comprising porcelain fired to such palladium based dental alloys.
Inventors
- 👤 Arun Prasad
Bibliographic Details
Claims Analysis
Total Claims: 12References Cited (Backward Citations)
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