Sintering of bimodal Y2O3-stabilized zirconia powder mixtures with a nanocrystalline component

Y2O3 - stabilized zirconia powders with average particle size of 10 nm and 430 nm were used to prepare bimodal powder mixtures by ultrasonic, ball mil ling and chemical precipitation techniques. Compacts were sintered between 1000 degrees C to 1340 degrees C for 10 min, 1 and 5h. German's packing mod al was used to describe the observed green and sintered density as well as to characterize the homogeneity of the compacts. The residual porosity was related to the non-homogeneous character of the porosity in the green bimod al compacts. Bimodal composition of 70 vol% coarse at 1200 degrees C yielde d the highest densification rate during sintering. (C) 1999 Acta Metallurgi ca Inc.