Interfacial reaction between the nickel-based superalloy and the Al2O3 crucible during vacuum induction melting

The effects of holding time on the interfacial reaction between a nickel-based superalloy and an Al2O3 crucible during the vacuum induction melting process were studied at 1450 °C. The results show that the reaction products at the interface are intermittently distributed and then gradually become dense and continuous as the holding time increases. The average thickness of the reaction layer increases and then decreases when the melting time is extended. Through microstructure characterization, the interfacial reaction layer extending from the boundary to the matrix consists of a continuous Al2O3 reaction layer and a discontinuous TiC layer. Finally, the process of the interface reaction is summarized.