Injection moulding of hollow silicon nitride parts using fusible alloy cores

An interesting method of injection moulding originally developed for the pl astic industry, is applied to technical ceramics in order to manufacture co mplex-shaped hollow parts at a reasonable cost. Silicon nitride parts are m oulded on fusible alloy cores that are subsequently removed by melting befo re the final sintering step. Several parameters are investigated to remove the alloy cores without creating defects. Best results are obtained with a ceramic mixture based on a polyethylene binder phase and by melting the cor es using an induction melting method. (C) 2001 Elsevier Science Ltd and Tec hna S.r.l. All rights reserved.