Mixedness and rheological properties of various binder systems were investigated for different volume fractions of silicon nitride fine powders. Thermoplastic binder system contained polythylene, polythylene wax, and other additives of small amount. Theoretical modeling was carried out qualitatively using total interfacial area ratio for non-dispersive mixing and total fracture surface area ratio of dispersive mixing. Flow analysis was carried out to characterize flow filed within the mixed employed. Mixedness of mixture was investigated by using scanning electron micrographs of the specimens mixed for five and thirty minutes, and using torque-mixing time curves as continuous mixing measure. In addition, a capillary rheometer was used to characterize moldability and relationship among mixture quality, viscosity, and torque curves. The results showed that mixture had good moldability and mixing quality up to silicon nitride volume fraction of 60%.
