Electrophoretic deposition of alumina from non-aqueous dispersions

Alumina has been deposited from an ethanolic suspension of commercial alumina powder stabilized with polyacrylic acid. The process has been studied by systematical variation of the deposition conditions and the properties of the suspensions. The microstructure of the deposited green plates is homogeneous except a thin porous layer at the electrode facing side. After sintering this porous layer is still present and causes a lower fracture strength of the electrode facing side in comparison to the solvent facing side of the compact. Methods for optimizing the microstructure are discussed.