Evaluation of fracture toughness of zirconia ceramics with heterogeneous yttrium distribution microstructures

Authors：Cui, Jinping; Zhao, Wei; Guan, Kang; Rao, Pinggen^*

Source：Journal of the Australian Ceramic Society, 2020, 56(4): 1229-1235.

DOI：10.1007/s41779-020-00474-0

• Fracture toughness
• Phase transformation depth
• V-notch
• Femtosecond laser

Yttrium stabilized tetragonal zirconia polycrystalline (Y-TZP) ceramics containing 2 mol% and 2.5 mol% yttria were prepared by mixing 3 mol% yttria-doped zirconia powders with yttria-free zirconia powders. The microstructures of the sintered samples were studied using SEM, XRD, and Raman spectra. In addition, an ultra-sharp V-notch (rho < 0.5 mu m) was induced by femtosecond laser to measure its actual fracture toughness by single-edge V-notched beam (SEVNB) method. The results reveal that mixture-based Y-TZP with 2.5 mol% yttria has deeper phase transformation depth, and fracture toughness of 6.4 MPa(.)m(1/2) is obtained. The heterogeneous distribution of the yttrium is taken account for the excellent properties.