High-temperature mechanical loss behaviour of 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP)

Systematic measurements of mechanical loss as a function of temperature, frequency and grain sizes were performed on 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) samples. The spectrum is composed of a mechanical loss peak and a high-temperature exponential background. The peak height depends on the grain size d as 1/d; the background dependence is 1/rootd. A new model has been developed to account for the mechanical loss spectrum as being due to the relative sliding of different types of grains. The peak is associated with small grains; the exponential background is interpreted as being due to the sliding of large grains.