High-pressure sintering mechanism of yttrium aluminum garnet (Y3Al5O12) transparent nanoceramics

We propose a sintering mechanism of transparent Y3Al5O12 nanoceramics under high pressure. Through analysis of the porosity, grain size and residual stress for the nanostructured YAG compacts prepared at high pressure and modest temperature (HPMT, 2.0–5.0 GPa and 300–500 °C), the nanosintering behavior was systematically investigated. High pressure can initiate the plastic deformation of nanograins to eliminate pores and enhance the local atomic diffusion among grain boundaries, thus producing fine nanostructured and near fully dense transparent YAG bulks.