Studies on the Castability of Co-Cr Alloy for Cast Plates

Part 1 : The Effects of Sprue Attachment Direction to Wax Plates and the Investment Direction of Refractory Models

Abstract

Co-Cr alloy is used more frequently than Ni-Cr alloy as a non-precious alloy for cast plates in Japan. However, since the melting point of Co-Cr alloy is very high, about 1300°C, and since it oxidizes easily, a vacuum-pressure casting machine capable of melting this alloy in a reduced atmosphere has recently been developed.
Using this vacuum-pressure casting machine, the authors studied the effects on the Co-Cr alloy of the attachment direction of sprues and the investment direction of refractory models.
The results clarified that in the vacuum-pressure casting method, sprue attachment direction and the investment direction of refractory models have a significant effect (p <0.01) on the castability of Co-Cr alloy.