Electrophoretic forming of Al2O3/Y-TZP layered ceramics from aqueous suspensions

Electrophoretic forming is emerging as an economical and reliable method for the fabrication of coatings and laminate ceramics. The method is very simple, but a major problem is the toxicity and environmental problems associated with the organic solvents usually employed as vehicle media. This work aims to obtain Al2O3/Y-TZP laminates by electrophoretic deposition using water as the liquid vehicle. The slip characteristics have been studied in terms of viscosity, zeta potential, and conductivity for both starting powders. Electrophoretic deposition was performed at constant values of current density to obtain the monolithics and layered materials. Very small variations in the deflocculating conditions allow control over the thickness of each layer in the laminate, providing a powerful method for obtaining tailored complex microstructures. (C) 1998 Elsevier Science Ltd.