Spray-Dried YSZ Ceramic Powders: Influence of Slurry Stability on Physical Characteristics of Agglomerates

Zirconia stabilized with 8 mol% yttria (YSZ) is the most effective material for use as electrolytes in solid oxide fuel cell. Ceramic powders of YSZ were synthesized in IPEN by coprecipitation route and are composed by fine particles (less than 01μm) with large surface area (~60m2.g-1). These powders have a strong tendency to agglomerate. and it make difficult the compaction process and to achieve a good density. To exert control over the compaction process. the powders were spray dried to obtain spherical granules. Thus the stability of slurries of these powders was studied by adding ammonium polyacrylate (Duramax D3005) as dispersant and the suspension stability was measured by electrophoretic mobilities. Slurries prepared with the better conditions were dried in a laboratory scale spray dryer. The prepared granules were characterized by morphology observation (SEM). surface area (BET). Vickers hardness and sintered ceramics bodies density were measured.