Preparation of Transparent 3Y-TZP Nanoceramics with No Low-Temperature Degradation

摘要

The progresses of the relative density, average grain size (GS), and maximum pore size entering into the final sintering stage are investigated in 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP) compacts in the range of 87%～99% theoretical density. It is found that during conventional pres-sureless sintering, the pores in the compact enlarged dramatically, which appears to be the major obstacle for preparing fully dense nanoceramics. Transparent 3Y-TZP nanoceramics with an average GS of 87 nm were prepared by exploiting microstructural refinement on nanoscale. The yields a maximal optical transmittance of 67% and shows no noticeable low-temperature degradation after 100 h aging at 134℃ under a hydrothermal pressure of two bars.