Titanium alloys for hip joint replacements

Pure titanium and titanium-base alloys are known to be the most corrosion resistant and biocompatible of all implant materials in the body. Pure titanium is preferably used for hip cup shells with polyethylene inserts. The high strength Ti-6AI-4V alloy is mainly used for anchorage stems of femoral components with wear-resistant CoCrMo metal or Al₂O₃ ceramic ball heads. Two new high-strength titanium alloys for implants, developed by Zwicker (Ti-5AI-2.5Fe) and by Semlitsch (Ti-6AI-7Nb) in the last decade, are already in clinical use.