Preparation of well-adhered γ-Al2O3 washcoat on metallic wire mesh monoliths by electrophoretic deposition

Washcoat deposited on metallic wire mesh monoliths was prepared using gamma-alumina powders by electrophoretic deposition under a relatively low electric voltage. The microstructure, phase structure and adhesion of washcoat were investigated by SEM, XRD, ultrasonic vibration and thermal shock. The results showed that the loading and adhesion of washcoat were affected obviously by the properties of suspension, such as the zeta potential and the amount of adding binders. A small quantity of aluminum isopropoxide could promote the cohesive affinity of washcoat in thermal shock. The adhesion of washcoat in ultrasonic vibration could be reinforced by increasing calcined temperature and adding a certain aluminum particles. It was also found that the washcoat immersed metal nitrate has excellent vibration-resistant ability. (c) 2006 Elsevier B.V. All rights reserved.