Investment Casting Technology Tailored to Near-Gamma TiAl Alloys

Investment Casting Technology Tailored to Near-Gamma TiAl Alloys

Audiovisual work

The present study reports on the investment casting of near-gamma TiAl intermetallics. The attention is paid mainly to the minimization of thermal mismatch strains generated in an intermetallic cast and a ceramic shell mould during cooling to room temperature. The mismatch strains stem from different thermal expansion coefficients of near-gamma TiAl alloy and the mould ceramics. A numerical modeling and optimization helped to spot those process parameters that are most influential with respect to the stress state in the cast-mould system. The optimization based on a sequential technique and on a modified random search routine yielded a processing window in which sound casts can be fabricated.

The present study reports on the investment casting of near-gamma TiAl intermetallics. The attention is paid mainly to the minimization of thermal mismatch strains generated in an intermetallic cast and a ceramic shell mould during cooling to room temperature. The mismatch strains stem from different thermal expansion coefficients of near-gamma TiAl alloy and the mould ceramics. A numerical modeling and optimization helped to spot those process parameters that are most influential with respect to the stress state in the cast-mould system. The optimization based on a sequential technique and on a modified random search routine yielded a processing window in which sound casts can be fabricated.

TiAl Intermetallics, Investment casting

DLOUHÝ, A., ZEMČÍK, L.

30.05.2005

University of Applied Sciences Aargau

Aargau

First Invited COST 526 Conference on Automatic Process Optimization in Materials Technology

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