Production issues in the manufacturing of TiAl turbine blades by investment casting

Abstract γ -TiAl based intermetallic alloys have attracted broad attention as a potential candidate for high-temperature structural applications. A careful selection of their composition and microstructure allows to obtain an interesting combination of oxidation resistance, creep resistance and high temperature strength for specific applications. Over the years, several complex manufacturing methods have been used for producing TiAl parts. In this work TiAl blades have been produced by means of investment casting. The work analyses the different production steps: design of a blade prototype, production of an ABS model by additive manufacturing that is used to make the wax model, preparation of the ceramic mold and centrifugal casting of the component. All the production issues related to TiAl alloy investment casting have been analyzed with the aim of setting up a tailored process able to produce sound components.