Study on Vacuum Suction Casting for TiAl-Based Alloys

Abstract:

A novel type of foundry method for TiAl-based alloy is presented in the present paper. The filling processes of Ti-47Al alloy sheet and blade have been studied via numerical simulation. The investigation results indicate that the filling fraction is enhanced by the increase of filling velocity and graphite throat diameter. The graphite throat diameter is the main parameter for the backward filling location in the process of vacuum suction casting. With the increase of mould temperature, the solid fraction is reduced. The alloy solidification begins from bottom to top. The TiAl sheet and the blade are produced by this method. The grain size of the sheet is in the range from 10 μm to 40 μm. There is no obvious shrinkage cavity

Key words:vacuum suction casting; numerical simulation; graphite throat diameter; solid fraction; filling fraction