What is an artificial joint made from?

Artificial joints: Typically they are made from surgical steel and a special plastic but sometimes parts are also made of ceramic.

Differing materials: Cobalt chrome alloys- very strong, and works well as a bearing surface. Titanium and its alloys- works well with contact to bone, more flexible than cocr, which is good sometimes. Ultrahigh molecular weight polyethylene- the main plastic that is used. Ceramics- can be polished smoother than cocr, and is supposed to lower wear when used against poly, or ceramic itself. Steel is not used anymore.

Metal and Plastic: Most hip and knee replacements are made of a combination of materials that have been shown through years of research and use to be the most durable. Surgeons can choose between titanium, chrome/cobalt alloys, ceramic, zirconium and plastic (usually polyethylene).