Tungsten-based bcc-superalloys

Applications from nuclear energy to rockets and jet engines are underpinned by advanced high temper- ature materials. Whilst state of the art, the performance of current nickel-based superalloys is funda- mentally limited to Ni’s melting point, T_m = 1455 ^◦C . Here, we develop an analogous superalloy concept but with superior high temperature capability by transitioning to a bcc tungsten base, T_m = 3422 ^◦C . This strategy involves reinforcing bcc β-W by β′ TiFe intermetallic compound, which results in impressive high temperature compressive strengths of 500 MPa at 1000 ^◦C . This bcc-superalloy design approach has wider applicability to other bcc alloy bases, including Mo, Ta, and Nb, as well as to refractory-metal high entropy alloys (RHEAs). By investigation of the underlying phase equilibria, thermodynamic modelling, characterisation and mechanical properties, we demonstrate the capability of ternary W-Ti-Fe tungsten- based bcc-superalloys as a new class of high temperature materials.