High strength, ductile cobalt-base dental alloy
Abstract
Abstract A low-cost cobalt-base alloy system suited for dental and other biomedical appliances is essentially free of carbon and molybdenum, and has an alloy base comprising cobalt, chromium, and nickel as essential major alloying elements and a member of the group comprising tantalum and niobium alloyed therewith as the major strengthening element to produce an alloy matrix having a structure which is ductile at room temperature, has high stacking fault energy to achieve further ductility and an average low electron hole number for the complete alloy matrix to prevent the formation of embrittling phases during cooling. The alloy system utilizes coherent strengthening compounds which form an integral part of the alloy matrix. Combinations of selected percentages, by weight, of cobalt, chromium, nickel, e.g. 35-45 percent cobalt, 20-32 percent chromium, and 30-40 percent nickel, are disclosed as the alloy base and is hardened by selected percentages of strengthening elements, e.g., tantalum and niobium, which have sufficient solubility in the alloy base to produce significant solid solution hardening and combine with cobalt to form coherent precipitate particles. Modifications are also disclosed.
Inventors
- 👤 M Mohammed
Bibliographic Details
Claims Analysis
Total Claims: 5References Cited (Backward Citations)
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