FABRICATION AND SINTERING OF FINE YTTRIA-DOPED CERIA POWDER

Yttria-doped ceria powder was prepared from oxalate precursors, The ox alate coprecipitation bath parameters were closely monitored and found to influence the sintering behavior of the subsequently obtained oxid e powders strongly, The use of concentrated (Ce,Y) metal nitrate solut ions and dilute neutralized oxalic acid for coprecipitation were ident ified as the most-important parameters, Following calcination at 700 d egrees C, compacts of such powders were sintered to high density (98%) at 1400 degrees C (4 h), Ball milling of the powder further reduced t he sintering temperature, Dry milling, for tape-casting applications o f the powder in particular, was more effective than wet milling, Tape- cast membranes were fired at 1400 degrees C (2 h), with resulting dens ities of 98%.