Injection molding of ceramic material was studied experimentally to determine molding conditions for successful processing of tensile and bending specimens. Mixtures of fine ceramic powder and binder system were prepared using a single screw extruder to be fed to the injection molding machine. Molding conditions as gate size, injection pressure, filling time, holding time and barrel temperature were varied when 55% ceramic mixture was molded. The commercially available flow analysis program, C-MOLD, was employed to predict filling behavior of the mixture for given molding conditions. Since ceramic mixture was solidified faster than pure polymeric melts due to high thermal conductivity and low specific heat, the gate size was more important than other injection molding variable. When the gate was enlarged to a proper size, short shots, defects, volume shrinkage and jetting phenomenon were avoided resulting in successful production of the specimens. The flow analysis also predicted the important experimental results that gate size, injection pressure and barrel temperature affect the performance of ceramic injection molding process. It was concluded that the satisfactory injection conditions for 55% ceramic mixture were injection pressure of 105MPa, barrel temperature of 240℃ and holding time of 10 sec with the proper gate size.
