Topologically close-packed phase promotion in a Ru-containing single crystal superalloy

It is widely accepted that Ru suppresses the formation of topologically close-packed (TCP) phases in advanced Ni-based single crystal superalloys. However, in the current study, the addition of a large amount of Ru promoted the precipitation of TCP phases in a Ni-based single crystal superalloy containing a high level of Cr during thermal exposure at both 1000 and 1100 °C. It is suggested that the addition of Ru increased the degree of Re and Cr supersaturation in the γ phase and resulted in the TCP phase formation.