Cobalt-chrome
Cobalt-chrome (Co-Cr) is a metal alloy of cobalt and chromium. Cobalt-chrome has a very high specific strength and is commonly used in gas turbines, dental implants, and orthopedic implants.[1]
The alloy composition used in orthopedic implants is described in industry standard ASTM-F75: cobalt with 27 to 30% chromium, 5 to 7% molybdenum, and limits on other important elements such as manganese and silicon, less than 1%, iron, less than 0.75%, nickel, less than 0.5%, and carbon, nitrogen, tungsten, phosphorus, sulfur, boron etc.[1] Besides cobalt-chromium-molybdenum (Co-Cr-Mo), cobalt-nickel-chromium-molybdenum (Co-Ni-Cr-Mo) is also used for implants.[2] The possible toxicity of released Ni ions from Co-Ni-Cr alloys and also their limited frictional properties are a matter of concern in using these alloys as articulating components. Thus, Co-Cr-Mo is usually the dominant alloy for total joint arthroplasty.[2]
References
- ↑ 1.0 1.1 ARCAM ASTM F75 CoCr Alloy
- ↑ 2.0 2.1 Biomimetic Porous Titanium Scaffolds for Orthopedic and Dental Applications, Alireza Nouri, Peter D. Hodgson and Cui’e Wen (Institute for Technology Research and Innovation, Deakin University, Australia)