Mechanism of lower activation energy for tetragonal ZrO 2 crystallite growth in the 3mol% yttria partially stabilized zirconia (3Y-PSZ) precursor powders

The crystallite growth behavior of the lower activation energy for the 3mol% yttria partially stabilized zirconia (3Y-PSZ) freeze dried precursor powders prepared by a co-precipitation process at 348K and pH=7 were investigated using an X-ray diffractometer (XRD), transmission electron microscope (TEM), selected area electron diffraction (SAED) and high-resolution transmission electron microscope (HR-TEM). The activation energy and kinetics equation of the tetragonal ZrO2 (t-ZrO2) crystallites growth from 3Y-PSZ freeze dried precursor powders are 11.4kJmol−1 and D2=2.6×103t0.28exp(-1.14×104RT), respectively. Furthermore, the mechanism of the lower activation energy crystallite growth from the aggregated crystallites to a larger crystallite is a lattice-plane-rotation-induced crystallite growth (LPRICG). The crystallites adjusted their d-spacing to connect with near crystallites and approached the crystallite growth by discontinuous lattice planes (DLPs) obviously rotating a small angle of 4.2° by TEM observed. Therefore, the mechanism of lower activation energy of the crystallite growth from the 3Y-PSZ freeze dried precursor powders can be obtained.