The goal of this research project is to fabricate a long lifetime ceramic Zr02 layer with special adhesion on orthopaedic femoral devices, particularly knees. Implantable orthopaedic femoral knee components usually are metallic because of the tensile forces present. Ceramic materials, such as A1203 or Zr02, generally exhibit many desirable properties, including lower ion release,less cut wear, and good biocompatibility. These latter materials, however, are poor in tension. Coatings are undesirable because adhesion cannot be guaranteed. High energy ion implantation is an accepted method that can provide the needed adhesion because the atoms are injected well below the surface, rather than deposited onto it. A technique for growing a thick surface layer of Zr02 on orthopaedic devices using ion implantation will be developed. The layer will interface the substrate through a blended transition region that spans a zone up to 0.1 micrometers in thickness. Zr02 layers up to 3 micrometers thick are possible. This technique should provide a long lifetime articulating surface to allow the implants to have the desirable bulk properties of titanium with a ceramic articulating surface.
