Characterisation of metal/mould interface on investment casting of γ-TiAl

Abstract

This paper describes the evaluation of different refractory compounds – SiO₂, ZrO₂ and Y₂O₃ – as face coats of investment casting shells for γ-TiAl.

The effect of the different refractories on the metal–mould interaction is studied in different aspects. Experimental results include characterisation of the constituents present at the metal/mould interface, the segregation profiles of residual elements, namely oxygen, from the interface to the inner part of the samples, the extension and microhardness of the samples external hard case and the samples surface finishing.

Keywords:

• TIAL
• INVESTMENT CASTING
• CERAMIC MOULD
• ZIRCONIA
• YTTRIA
• SILICA
• GRAPHITE
• CERAMIC CRUCIBLE