Development of a database for the prediction of phases in Pt-Al-Cr-Ru alloys for high-temperature and corrosive environments: Al-Cr-Ru

Platinum-based alloys for high-temperature corrosive environments are being developed which have microstructures that are analogous to the γ/γ′ microstructure of the nickel-based superalloys. The need for a predictive thermodynamic database for these alloys was identified. Because experimental studies suggested that such a database should be based on Pt-Al-Cr-Ru, the Al-Cr-Ru system is of importance in this research programme. Using the CALPHAD method and Thermo-Calc software, existing binary data were used to optimise a ternary database for Al-Cr-Ru against available experimental ternary data. The database gives good predictions with regards to phase equilibria in the system as well as the nature of the primary solidification phases.