Hydraulic alumina binder for extrusion of alumina ceramics

Abstract

The present work describes the effect of hydraulic alumina (HA) as a new inorganic binder on extrusion of alumina ceramics. The addition of a small amount of HA imparted significant flowability and rigidity to the extruded alumina. Under optimum processing conditions such as amounts of HA and water, and curing period, alumina rods and tubes were successfully extruded using a single screw extruder. Sintered specimens have achieved a relative density of 97% after sintering at 1600 degrees C for 2 h. Dense alumina samples prepared using organic and inorganic binders had similar mechanical properties, that is, Young's modulus >380 GPa and H-v>2000. These results suggest that HA is a new kind of inorganic binder applicable to the extrusion of ceramics.