Prosthetic hip joint having a polycrystalline diamond articulation surface and a plurality of substrate layers

A prosthetic hip joint comprising:

• an acetabular cup including a sintered polycrystalline diamond compact,
• a substrate located on said acetabular cup polycrystalline diamond compact,
• an acetabular cup diamond table sintered to said acetabular cup substrate on said acetabular cup polycrystalline diamond compact,
• acetabular cup solvent-catalyst metal located in said acetabular cup diamond table,
• a gradient transition zone between said acetabular cup substrate and said acetabular cup diamond table in said acetabular cup polycrystalline diamond compact, said acetabular cup gradient transition zone having a substrate side and a diamond table side, said acetabular cup gradient transition zone having both acetabular cup solvent-catalyst metal and diamond therein, and said acetabular cup gradient transition zone exhibiting a transition of ratios of percentage content of acetabular cup solvent-catalyst metal to diamond from one side of said gradient transition zone to another such that at a first point in said acetabular cup gradient transition zone near said substrate side, the ratio of percentage content of acetabular cup solvent-catalyst metal to diamond is greater than it is at a second point in said acetabular cup gradient transition zone closer to said diamond side than said first point,
• chemical bonds between said acetabular cup diamond table and said acetabular cup substrate which tend to secure said diamond table to said substrate,
• an acetabular cup load bearing and articulation surface on said polycrystalline diamond compact, said acetabular cup load bearing and articulation surface including polycrystalline diamond, said acetabular cup load bearing and articulation surface being formed to present a shape that is at least partially concave spherical and against which a femoral head may articulate,
• a femoral head for articulation against said acetabular cup load bearing and articulation surface, said femoral head including a sintered polycrystalline diamond compact,
• a first femoral head substrate layer located on said femoral head polycrystalline diamond compact,
• a second femoral head substrate layer located on said femoral head polycrystalline diamond compact, said second substrate being in proximity to said first substrate,
• a femoral head diamond table sintered to said first femoral head substrate layer on said femoral head polycrystalline diamond compact,
• femoral head solvent-catalyst metal located in said femoral head diamond table,
• a gradient transition zone between said first femoral head substrate layer and said femoral head diamond table in said femoral head polycrystalline diamond compact, said femoral head gradient transition zone having a substrate side and a diamond table side, said femoral head gradient transition zone having both femoral head solvent-catalyst metal and diamond therein, and said femoral head gradient transition zone exhibiting a transition of ratios of percentage content of femoral head solvent-catalyst metal to diamond from one side of said gradient transition zone to another such that at a first point in said femoral head gradient transition zone near said substrate side, the ratio of percentage content of femoral head solvent-catalyst metal to diamond is greater than it is at a second point in said femoral head gradient transition zone closer to said diamond side than said first point,
• chemical bonds between said femoral head diamond table and said first femoral head substrate layer which tend to secure said diamond table to said substrate first femoral head substrate, and
• a femoral head load bearing and articulation surface on said polycrystalline diamond compact, said femoral head load bearing and articulation surface including polycrystalline diamond, said femoral head load bearing and articulation surface being formed to present a shape that is at least partially convex spherical.