FUNCTIONALLY GRADED ALL CERAMIC HIP JOINT - Advanced Biomaterials: Fundamentals, Processing, and Applications - page 335

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Y Y

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.239415 2 4 8 45

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Figure 10.12. E-fi eld strength calculation, performed in ANSYS 5.7, of the electrodes to pro-
cess the cup insert. [Anné, 2005a].

Figure 10.13. Counter-electrode with insulating cap in which well-defi ned holes are made
for EPD of acetabular cup inserts. [Anné, 2005a].

uniform electrical fi eld. Therefore, automatic rigid positioning devices were
designed and constructed to prepare ball-heads and acetabular cup inserts.
The EPD process was fully automated. The displacement of the counter-
electrode, the voltage, and the speed of the pumps can be programmed as a func-
tion of time. Additionally, the current and suspension conductivity is logged
during the EPD process.
Since the procedures for the production of ball-heads has been described
elsewhere [Anné et al., 2006d], the procedures for acetabular cup inserts are
described here in some detail. The acetabular cups are deposited on an electrode
that has the shape of the outer surface of the cup insert. The counter electrode has
the shape of a ball and is positioned in the centre of the deposition electrode.