Electrophoretic deposition of sol-gel ceramic microcomponents using UV-curable alkoxide precursors

A process was developed, by which piezoceramic microparts can be produced directly using liquid metal-organic lead-zirconate-titanate (PZT) precursors. Electrophoretic deposition (EPD) was used as the shaping method, the precursors were PZT-sols synthesized by a modified sol-gel technique. After EPD into a microstructured mould, simultaneous to the gelation of the sol, the deposited gel-body was then dried and the mould was removed, followed by pyrolysis of the organics and final sintering. Special emphasis was placed on the development of the precursor. By introducing polymerisable chelating agents into the synthesis, the gel can additionally be hardened by radical polymerisation. By using UV-sensitive initiators, the gel-hardening can be performed by photo-induced polymerisation. The resulting solid gel shows considerably better mechanical strength than comparable inorganic gels due to mutually interpenetrating inorganic and organic networks in the gel instead of just an inorganic network built up by gelation. (C) 1997 Elsevier Science Limited.