INTERFACE REACTION BETWEEN CERAMIC MOULDS AND Ti46Al1B AS-CAST VALVES
陶瓷壳型面层材料与Ti46Al1B阀门铸件的界面反应

Al2O3 and Y2O3 were used as surface materials of shell mould to centrifugal--cast Ti46Al1B (atomic fraction, %) valves, the interface reaction between shell and alloy and its mechanism were analyzed by SEM and XRD, and oxygen increment in the castings was measured by gas analysis. The results show that the reaction layer thicknesses of Y2O3 and Al2O3 shells are about 90 and 170 μm, respectively, indicating Y2O3 shell has better thermodynamic stability and smaller increment of oxygen in casting than Al2O3 shell, which is accordant with thermodynamic calculation. So the Y2O3 mould is fitter for casting Ti46Al1B valves than Al2O3 mould.