US Patent 8956403 Medical implant including a magnesium-based tie layer

A medical implant includes a metallic base, a tie layer, and at least a first layer overlying an outer surface of the tie layer. The tie layer is bonded to at least a portion of a surface of the metallic base. The tie layer includes magnesium or a magnesium-based alloy. The tie layer can have an outer surface comprising dendritic grains. The tie layer can have a rough outer surface defined by pores, projecting grain structures, and/or projecting particles. A method of producing a tie layer on a medical device includes applying magnesium or a magnesium-based alloy to the medical device and cooling the magnesium or the magnesium-based alloy to produce a rough outer surface.