Grain growth kinetics and segregation in yttria tetragonal zirconia polycrystals

Abstract

Abstract The aim of this work is the determination of the grain growth kinetic law in 4 mol.% yttria tetragonal zirconia polycrystals. To that purpose, several sets of slices of 4 mol.% yttria tetragonal zirconia polycrystals were annealed for different times at a constant temperature as well as at a constant time for different temperatures. The mean grain size was determined by means of scanning electron microscopy observations of the annealed surfaces, after fitting the grain size distributions to lognormal functions. A power law of the mean grain size versus the annealing time was found to describe the experimental results. Surprisingly, the same power law was shown to account for the dependence of the grain size standard deviations versus time. A correlation of these results with a model reported in the literature on the yttrium segregation to grain boundaries is discussed.