In order to successfully shape green ceramics with complex geometry by means of electrophoretic deposition, a rigid and accurate mechanical electrode-positioning device is essential. Additionally, the design of the deposition and counter electrodes is crucial to manufacture near-net-shape components. K.U.Leuven designed and built a rigid computerised positioning and EPD device composed of; a sledge, linear motor, drivers, computer interfaces, power supply, peristaltic pumps, thermocouple and temperature control unit. Electrical field calculations were performed to assist the design of proper electrodes to shape ball-heads for hip-prosthesis. Basic know-how was obtained on the optimal flow of the suspension through the deposition cell.
The set-up allows to automatically running pre-programmed EPD experiments with on-line logging of the voltage, current, suspension temperature and conductivity during the experiment. Due to the complex geometry of the ball-head shape, a sequence of electrodes has to be used in order to achieve a near-net-shaped ball-head deposit. The shaping capabilities of the EPD processing technology and set-up have been demonstrated for homogeneous Al2O3 and functionally graded ZrO2-Al2O3 ball-heads and liners. The potential applicability of the EPD technique is not limited to the Al2O3-ZrO2 system, but covers the broad range of ceramic, metals and polymer materials, providing a suitable suspension is developed. The shape of the electrodes used, which can be designed according to the envisaged application, defines the shaping potential of the developed EPD set-up.