Comparison of dispersants performance on the suspension Lu2O3:Eu3+ stability and high-density compacts on their basis

The conditions for obtaining a stable Lu2O3:Eu3+ suspension of spherical particles with a diameter of 100 nm using three dispersants possessing an electrosteric stabilizing effect (Dolapix CE 64, Darvan 821 A, Darvan C-N) have been studied. It has been shown that in colloidal processing of ceramics the packing density and microstructure of green bodies can be controlled by regulating the interactions between ceramic particles in the suspension. The influence of the molecular weight and concentration of the dispersant on the stability of Lu2O3:Eu3+ suspensions containing 5–10 vol.% of the solid loading has been considered. It has been determined that use of Dolapix CE 64 with a concentration of 1 mass.% in the alkaline pH range allows to obtain suspensions with high stability and low viscosity (∼1.7 сP). Such suspensions were used to produce compacts with a maximum relative density of ∼52% and uniform density distribution by the pressure slip casting method. The obtained compacts were densified into translucent Lu2O3:Eu3+ ceramics by the vacuum sintering method.