Additive Manufacturing of Zirconia Ceramic via Nanozirconia Suspension Micro-Jetting and Bonding

The ceramic green bodies with different structures can be formed via binder micro-jetting and bonding additive manufacturing technology. However, the density, strength and surface quality of the sintered ceramic bodies are low. The nanozirconia suspension was used as a jet solution to substitute a conventional organic binder, and the effect of nanozirconia suspension jet amount on the properties of additive manufactured zirconia ceramics after sintering was investigated. When the nanozirconia suspension jet amount increases from 0 to 175%, the line shrinkage and surface roughness of sintered zirconia ceramics decrease significantly, and the reduction rates are 6%–8% and 57%, respectively, while the relative density, flexural strength and hardness increase considerably, and the increase rates are 18.1%, 124.0%, and 187.0%. The nano-sized zirconia particles can fill in the pores of the zirconia powder layer after introducing the nanozirconia suspension, thus improving the green density and the sintering quality of the zirconia ceramic. This provides an effective method for rapid manufacturing complex and compact ceramic parts.