Abstract Scope |
Nuclear fusion, Generation-IV fission reactors and gas turbines demand advanced materials with ever-improved high temperature performance. Refractory metals have exceptionally high melting points >2000°C, far higher than nickel-based fcc-superalloys, <1450°C. However, ordered-intermetallic precipitate reinforcement is not exploited, which is a potent strategy in γ-γ’ fcc-superalloys for strength, creep resistance and ductility. There is great scope for the exploitation of a β-β’ ‘bcc-superalloy’ strategy for bcc refractory metals, and also within compositionally complex alloys (CCAs, or high entropy alloys, HEAs).Design and development of precipitate reinforced refractory metal alloys will be showcased. New design strategies exploit the two-phase field bcc β (Ti) to β’ TiFe, whereby precipitates can be produced within a matrix of β (Mo,Ti) and also β (W,Ti). Such precipitation offers superalloy-like β-β’ microstructures with development focused on: (1) Microstructure control, (2) Properties and deformation behaviour, seeking to demonstrate bcc-superalloys as a new class of high temperature materials. |