Mmr. Boutz et al., EFFECT OF ADDITIVES ON DENSIFICATION AND DEFORMATION OF TETRAGONAL ZIRCONIA, Journal of Materials Science, 29(20), 1994, pp. 5374-5382
The effect of additives (Bi2O3, Fe2O3) on densification and creep rate
s of tetragonal ZrO2-Y2O3 has been investigated. In Bi2O3-doped Y-TZP,
a reactive liquid forms at temperatures above 800-900 degrees C, whic
h leads to a strong enhancement of densification for concentrations of
1-2 mol% Bi2O3. However, during cooling from the processing temperatu
re a strong, undesirable transformation of the tetragonal to the monoc
linic phase occurs. The addition of 0.6-1.2 mol% FeO3/2 promotes densi
fication without destabilizing the tetragonal phase. A concentration o
f 1.2 mol%, however, induces discontinuous grain growth, while this is
not the case for 0.6 mol%. Creep rates of Y-TZP were enhanced by a fa
ctor of 4-6 by adding 0.6 mol% FeO3/2.