An Improving Densification in Spark Plasma Sintering Ultrafine-grained Y2O3 Transparent Ceramic by Particle Fracture and Rearrangement

Herein, we report a new strategy on an improving densification in spark plasma sintering (SPS) ultrafine-grained Y2O3 transparent ceramic using anisotropic-shaped nanorod powders. At the low temperature stage (<600°C), fracture and rearrangement of nanorod powders will appear which can further improve the initial density of particle compact and reduce the initial particle size. When the temperature reaches beyond 600°C, the sintering efficiency of nanorod powder compact will exceed that of the green body packed by spherical powders. The ceramic sample sintered at 1300°C from nanorods is transparent with ultra-fine grain and shows good optical and mechanical properties, while the corresponding ceramic from near-spherical nanocrystalline powders is not dense enough and opaque.