Preparation And Characterization Of Printable AM/MBAM Gel-based Zirconia Slurry

In the 3D printing of ceramic materials,the most serious problem is the high volume of the polymers that added into the slurry,which can result in the low density of the sintered parts.Gel-casting is a near-net-shape fabricate process that use high solid content(>50 vol%)and low polymer contain(<4 vol%)slurries to fabricate full dense ceramic parts.By adding water-soluble polymers such as PEG/PVP and disparate the reactive monomers(AM/MBAM)with the initiator,the prepared two-component slurry with high solid content and low polymer contain can be storable for several days under room temperature.Once mixed,the curing behavior of the mixture can be controlled by adjusting initiator and catalyst.The effect of water-soluble polymers on slurry properties such as the stability,rheology and curing behavior was studied.The curing behavior of the mixture was measured under different temperature and initiator/catalyst amount.The printing behavior of the slurry was tested by adjusting printing parameters such as printing speed,extrusion pressure and layer height.The result shows that stability,yield stress and apparent viscosity of the slurries was increased by adding PEG/PVP.Surface exfoliation of the green body was eliminated due to the binder effect of PEG/PVP.The curing behavior of the mixture can be controlled by adding different amount of initiator or catalyst.The width of extruded line was determined by viscosity of the slurry,and also related to printing parameters such as extrusion pressure?printing speed and layer height.Density of the extruded line after sintered up to 99.3%.The adhesive among the layers is in good condition with no deformation of the printed ceramic part,the sintered part has a density of 96.3% with homogeneous microstructure.