Injection molding of ceramic turbocharger rotor was investigated to determine proper molding conditions for silicon nitride. Various molding conditions were employed to evaluate their effects on injection molding of the ceramic mixture and pure polypropylene. Process variables such as injection pressure, holding pressure, holding time, injection speed, mold temperature etc. were varied for experiments. Internal cross-section of injection molded product was observed by SEM picture. MOLDFLOW was used for simulation of filling.
The results indicated that ceramic injection molding showed a jetting phenomenon as a major problem. It was also discovered that the difference in shrinkage between ceramic mixture and polypropylene was significant. Both filling simulation and experimental results revealed that injection pressure and injection speed are important parameters for successful injection molding of ceramic product.