Spark plasma sintering of high-toughness ZrO2 materials doped with yttrium

Zirconia powders doped with yttrium prepared by special liquid-phase precipitation method were sintered by spark plasma sintering (SPS) to obtain high performance samples. The microstructure, phase composition, and mechanical properties of the samples were studied. The results of X-ray diffraction (XRD), Raman spectrum, and transmission electron microscope (TEM) show that the phase is tetragonal. The powders with large surface area and high sintering activity, due to small crystallite size, could be densified at 1100°C. The highest relative density of the sample obtained at 1300°C is higher than 99% (the tetragonal phase is 6.08 g/cm3). The Hv and KIC are 13.76 GPa and 15.4 MPa·m1/2, respectively.