Abstract: Coatings for use in artificial joints and other implanted medical devices. The coatings comprise a dual layer structure vapor deposited atop a medical grade substrate, such as cobalt chromium. The dual layer structure comprises a first ceramic layer vapor deposited atop at least a portion of the substrate and a second ceramic layer deposited atop the first ceramic layer. The first ceramic layer is formed of a material which has particularly good adhesion to the substrate, and the second ceramic layer from a material exhibiting particularly high hardness and good wear characteristics. The vapor deposition process is controlled so as to form a graded interface between the two ceramic layers to form a dual layer coating which resists delamination, adheres well to the substrate, and exhibits good wear characteristics in situ.

Abstract: Coatings of doped chromium nitride protect forming members such as dies from the corrosive effects of molten aluminum and other reactive metals.