Optimization of the Processing of 8-YSZ Powder by Powder Injection Molding for SOFC Electrolytes

The development of a new multicomponent thermoplastic binder system for injection molding of yttria‐stabilized zirconia (8‐YSZ) bars based in polypropylene and paraffin wax (PW) is presented in this paper. The surface coating of YSZ powder with stearic acid in a high‐performance dispersing instrument reduced the viscosity of the feedstock by one order of magnitude with respect to a feedstock with the same composition and uncoated powder. This fact allowed us to obtain a feedstock with a viscosity curve more suitable for the injection process without requiring high proportions of PW in the binder composition. The density of the samples was >98% and the conductivity of sintered parts are comparable to those of samples uniaxially compacted, around 0.10 S/cm at 900°C.