A coating of blue-black or black oxidized zirconium of uniform and controlledthickness on a zirconium or zirconium alloy material is accomplished throughthe oxidative treatment of an amorphous zirconium or zirconium alloy substratehaving an altered surface roughness. An oxidized zirconium coating of uniformand controlled thickness is especially useful on orthopedic implants of zirconiumor zirconium-based alloys to provide low friction, highly wear resistant surfaceson artificial joints, such as, but not limited to, hip joints, knee joints, shoulders,elbows, and spinal implants. The uniformly thick oxidized zirconium surfaceof controlled depth on prostheses provide a barrier against implant corrosioncaused by ionization of the metal prostheses. The invention is also useful innon-articulating implant devices such as bone plates, bone screws, etc.
