Fabrication of Nanocrystalline Superplastic ZrO2 Ceramics

An average particle size of d ≈ 300 nm can be reduced to a nanocrystalline size of about 10 nm or less after 400 h HEBM process. Amorphous-like phase is also observed among the nanocrystalline particles. Using SPS, the nanocrystalline powder can successfully be consolidated into a dense nanocrystalline ZrO2-spinel composite of d ≈ 90 nm. As compared with the data for submicro-grain composite with d = 350 nm, nano-crystalization increased the strain rate by one order of magnitude or lowered the deforming temperature by about 100 K.