Correlations between strength and acoustic properties in yttria-stabilized zirconia polycrystals

The strength, bulk density, and acoustic properties of nine Y2O3-stabilized ZrO2 polycrystals (Y-TZPs) were evaluated in the present study. The samples showed a strong correlation between strength and acoustic properties, a phenomenon that reflects the internal bulk structure, especially the pore size distribution. Strength increased with a decrease in the attenuation coefficient and with an increase in the transverse wave velocity of the samples. On the other hand, the bulk density of the samples showed no clear relationship with strength. Bulk density reflects only the amount of pore volume in the test piece, whereas the acoustic properties are sensitive to defects or inhomogeneities in the micro-structure. The attenuation coefficient and transverse wave velocity thus seem to be good parameters for estimating the strength of Y-TZPs