Abstract
Surface coating of Si3N4 powder with an alumina precursor was achieved by a sol-gel method using aluminum isopropoxide. Electrophoretic data showed the surface-coated Si3N4 powder behaved like alumina. Consolidation of the surface-coated powder was attempted by an electrophoretic deposition (EPD) technique. EPD rate was improved for the surface-coated powder. Sintering characteristics and fracture toughness were investigated for EPDed compacts. It was demonstrated that the surface coating of Si3N4 powder with alumina precursor had the advantage of not only the improvement of suspension stability, but also the addition of sintering aid.
