| abstract |
Embodiments are directed to radiopaque implantable structures (e.g., stents) formed of cobalt-based alloys that comprise cobalt, chromium and one or more platinum group metals, refractory metals, or combinations thereof. Platinum group metals include platinum, palladium, ruthenium, rhodium, osmium, and iridium. Here, the term “refractory metals” include zirconium, niobium, rhodium, molybdenum, hafnium, tantalum, tungsten, rhenium, as well as the precious metals silver and gold. In one embodiment, the one or more included platinum group or refractory metals substitute for nickel, such that the alloy is substantially nickel free. The stents exhibit improved radiopacity as compared to similar alloys including greater amounts of nickel. |